CN107786250B

CN107786250B - Feedback method and device for channel state information

Info

Publication number: CN107786250B
Application number: CN201610709322.2A
Authority: CN
Inventors: 颜敏; 陈庆春; 吴涛
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2016-08-23
Filing date: 2016-08-23
Publication date: 2021-04-09
Anticipated expiration: 2036-08-23
Also published as: WO2018036253A1; CN107786250A

Abstract

Embodiments of the present invention provide a method and device for feeding back channel state information. The method includes: a receiving end acquires time-domain channel state information CSI between each pair of antennas; the receiving end sends a time-domain CSI encapsulation packet to a transmitting end according to the time-domain CSI between the pairs of antennas; wherein, the The time-domain CSI encapsulation package is used to indicate to the transmitting end the field position where each effective path is located between each antenna pair, and the effective path gain information of the path corresponding to each antenna pair; the field position where the effective path is located It is used to instruct the transmitting end to determine the delay information of the effective path according to the field position where the effective path is located and the preset unit delay; the effective path is the path whose gain is greater than the preset gain threshold in the path. . This method greatly saves the overhead of feeding back CSI from the receiving end to the transmitting end.

Description

Feedback method and device of channel state information

Technical Field

The present invention relates to communications technologies, and in particular, to a method and device for feeding back channel state information.

Background

In today's wireless communication systems, a number of techniques are employed to improve the performance of the system, such as: the adoption of the technologies such as scheduling, precoding, power control technology, adaptive scheduling technology and the like all require the terminal to obtain accurate Channel State Information (CSI), so that the terminal can transmit data according to the CSI. Currently, there are two methods for acquiring channel state information: one is that the sending end estimates the CSI when the data is sent currently, and the other is that the receiving end estimates the CSI and then feeds back to the sending end. For the case that the sending end estimates the CSI, the method is suitable for a scene or a system where channel reciprocity holds, for example, a Time Division Long Term Evolution (TD-LTE) system; for the condition that the receiving end estimates the CSI and feeds back the CSI to the transmitting end, the method is suitable for a scenario where channel reciprocity is poor or not established, such as an EDD-LTE (Frequency Division duplex Long Term Evolution) system.

With the increase of the bandwidth of the communication system, the feedback quantity of the CSI estimated by the receiving end is multiplied, and the reduction of the feedback quantity of the CSI is beneficial to improving the spectrum utilization rate and optimizing the system performance, so that the improvement of the performance of the whole system is restricted by the feedback of the CSI. In an Institute of Electrical and Electronics Engineers (IEEE) 802.11n/ac system, a channel estimation module estimates channel gain on each subcarrier, and CSI feedback is frequency-domain CSI information, since the number of subcarriers in the 802.11n system is small and the frequency-domain feedback overhead is not large, IEEE802.11ay adopts techniques such as channel aggregation and Multiple-Input Multiple-Output (MIMO) and the like, which have more subcarriers and bring great overhead by adopting frequency-domain CSI feedback, the frequency-domain feedback scheme is not suitable for the IEEE802.11ay system; in the ieee802.11ad system, when time-domain CSI feedback is performed, time delay information of all taps is quantized and then fed back, and the 11ay system adopts channel convergence, MIMO and other technologies, so that the number of channel taps is large, and the feedback scheme also brings great feedback overhead.

Therefore, how to reduce the CSI delay feedback overhead in the ieee802.11ay system becomes a technical problem to be solved at present.

Disclosure of Invention

The embodiment of the invention provides a method and equipment for feeding back channel state information, which are used for solving the technical problem that a CSI feedback scheme in the prior art cannot be applied to an IEEE802.11ay system, namely the time delay feedback overhead of CSI cannot be reduced.

In a first aspect, an embodiment of the present invention provides a method for feeding back channel state information, including:

a receiving end acquires time domain Channel State Information (CSI) between each antenna pair;

the receiving end sends a time domain CSI encapsulation packet to the sending end according to the time domain CSI between each antenna pair; the time domain CSI encapsulation packet is used for indicating the field position where each effective path between each antenna pair is located and the effective path gain information of the path corresponding to each antenna pair to the transmitting end; the field position of the effective diameter is used for indicating the sending end to determine the time delay information of the effective diameter according to the field position of the effective diameter and the preset unit time delay; the effective path is a path of which the gain is greater than a preset gain threshold in the path.

In the method for feeding back channel state information provided by the first aspect, the time domain CSI between each antenna pair is obtained by the receiving end, and the time domain CSI encapsulation packet is sent to the sending end according to the time domain CSI between each antenna pair, so that the sending end can obtain the field position of the effective diameter between each antenna pair according to the time domain CSI encapsulation packet, and further determine the delay information of the effective diameter according to the field position of the effective diameter and the preset unit delay, and the receiving end does not need to quantize the delay information of all the effective diameters between each antenna pair and feed back the delay information to the sending end, thereby greatly saving the delay feedback overhead of the receiving end.

In one possible design, the time-domain CSI encapsulation packet includes a delay indication field, an effective path indication field, and an effective path gain indication field;

the time delay indication field is used for representing a byte number of a last effective path between any antenna pair corresponding to the effective path indication field;

each byte in the effective diameter indication field corresponds to 8 diameters, and the effective diameter indication field is used for indicating the field position of each effective diameter between the antenna pairs to the sending end so that the sending end can obtain the time delay information of the effective diameter according to the field position of the effective diameter and the unit time delay;

the effective path gain indication field is used for indicating effective path gain quantization information of each antenna pair corresponding path to the transmitting end.

In one possible design, the delay indication field is an 8-bit indication field.

In one possible design, the delay indication field is further used to characterize a length of the effective path indication field.

In the feedback method of the channel state information provided by each possible design, the field position of each effective diameter between each antenna pair is represented to the sending end by adopting different fields, so that the sending end can obtain the time delay information of the effective diameter between each antenna pair according to the field position of each effective diameter, and the time delay information of all the effective diameters between each antenna pair is not required to be quantized and fed back to the sending end by the receiving end, thereby greatly saving the time delay feedback overhead of the receiving end; on the other hand, when the number of paths between an antenna pair is greater than 63, more paths can be located at field positions to the transmitting end through the setting of 8 paths corresponding to one byte in the delay indication field and the effective path indication field, so that the transmitting end can obtain delay information on all effective paths between the antenna pair.

In a possible design, the sending, by the receiving end, a time domain CSI encapsulation packet to the sending end according to the time domain CSI between the antenna pairs specifically includes:

the receiving end determines a time domain Multiple Input Multiple Output (MIMO) channel matrix according to the time domain CSI between each antenna pair, wherein the time domain MIMO channel matrix comprises channel impulse response of at least one path, and one path comprises at least one path;

the receiving end encodes the path on each path in the time domain MIMO channel matrix according to bytes, and acquires a bit array corresponding to each path, a byte number L corresponding to the last effective path on each path on the bit array and the number P of the effective paths on each path according to the encoded path; wherein each bit of the bit array corresponds to a path on the path;

the receiving end carries out binary coding on the L corresponding to each path, and takes the coded L corresponding to each path as a time delay indication field of each path;

the receiving end deletes the bit position behind the L in the bit number group corresponding to each path according to the L corresponding to each path to obtain a new bit array, and uses the new bit array as an effective path indicating field of each path;

the receiving end obtains the gain quantization information of the effective diameter of each path according to the number P of the effective diameters on each path and the gain information after the quantization of each effective diameter on each path, and takes the gain quantization information of the effective diameter as an effective diameter gain indication field of each path;

and the receiving end determines the time domain CSI encapsulation packet according to the time delay indication field of each path, the effective path indication field of each path and the effective path gain indication field of each path, and sends the time domain CSI encapsulation packet to the sending end.

In a possible design, the determining, by the receiving end, a time-domain MIMO channel matrix according to the time-domain CSI between the antenna pairs specifically includes:

the receiving end numbers the sending antenna and the receiving antenna respectively;

the receiving end sequentially obtains channel impulse response between antenna pairs formed by each transmitting antenna and each receiving antenna according to the serial numbers of the transmitting antennas and the serial numbers of the receiving antennas;

and the receiving end acquires the time domain MIMO channel matrix according to the channel impulse response between each antenna pair.

the receiving end receives at least one first beam optimization protocol (BRP) frame sent by the sending end;

the receiving end acquires a TRN domain in each first BRP frame;

and the receiving end measures the channel impulse response between each antenna pair according to each TRN domain, and determines the time domain MIMO channel matrix according to the measurement sequence of each TRN domain and the channel impulse response between each antenna pair.

In a possible design, after the receiving end determines a time-domain MIMO channel matrix according to the time-domain CSI between each antenna pair, the method further includes:

and the receiving end sends the arrangement sequence of the channel impulse responses in the time domain MIMO channel matrix to the sending end.

In a possible design, the determining the time-domain CSI encapsulation packet according to the delay indication field of each path, the effective path indication field of each path, and the effective path gain indication field of each path, and sending the time-domain CSI encapsulation packet to the sending end specifically includes:

the receiving end packages a time delay indication field, an effective path indication field and an effective path gain indication field of the same path into a time domain CSI package packet corresponding to the path;

and the receiving end respectively sends the time domain CSI encapsulation packets corresponding to each path to the sending end according to the arrangement sequence of the channel impulse responses in the time domain MIMO channel matrix.

the receiving end packages the delay indication field, the effective path indication field and the effective path gain indication field corresponding to each path into a time domain CSI package sub-package;

and the receiving end packages each time domain CSI package sub-packet into the time domain CSI package packet according to the arrangement sequence of each channel impulse response in the time domain MIMO channel matrix, and sends the time domain CSI package packet to the sending end.

In a possible design, the sending the time domain CSI encapsulation packet to the sending end specifically includes:

the receiving end carries out coding modulation processing on the time domain CSI encapsulation packet to obtain a modulated CSI encapsulation packet;

and the receiving end carries the modulated CSI encapsulation packet in a second BRP frame and sends the second BRP frame to the sending end.

In a possible design, the second BRP frame carries first indication information and second indication information, where the first indication information is used to indicate to the sending end that the second BRP frame carries the modulated CSI encapsulation packet, and the second indication information is used to indicate to the sending end the number of effective paths in each path.

The feedback method of the channel state information provided by each possible design determines a time domain MIMO channel matrix according to time domain CSI between each antenna pair through a receiving end, codes the path on each path in the time domain MIMO channel matrix according to bytes, and acquires a bit array corresponding to each path, a byte number L corresponding to the last effective path on each path on the bit array and the number P of the effective paths on each path according to the coded path; then the receiving end carries out binary coding on the L corresponding to each path, and the coded L corresponding to each path is used as a time delay indication field of each path; deleting the bit position behind the L in the bit number group corresponding to each path according to the L corresponding to each path to obtain a new bit array, and indicating the effective path indicating field of each path in the new bit array; and the receiving end obtains the gain quantization information of the effective diameter of each path according to the number P of the effective diameters on each path and the gain information after the quantization of each effective diameter on each path, and uses the gain quantization information of the effective diameter as the gain indication field of the effective diameter of each path, thereby determining a time domain CSI encapsulation packet and sending the time domain CSI encapsulation packet to the sending end according to the time delay indication field of each path, the effective diameter indication field of each path and the gain indication field of the effective diameter of each path, the time domain CSI encapsulation packet obtained by adopting the method can represent the field position of each effective diameter between each antenna pair to the sending end, so that the sending end can obtain the time delay information of the effective diameter between each antenna pair according to the field position of each effective diameter, and the receiving end does not need to feed back the time delay information of all the effective diameters between each antenna pair to the sending end after the time delay information of each antenna pair, the time delay feedback overhead of a receiving end is greatly saved; on the other hand, the length of the effective path indication field is reduced by deleting the bit representing the ineffective path after L, so that the size of a time domain CSI encapsulation packet is reduced, and the time domain feedback overhead of a receiving end is further reduced; further, when the number of paths between an antenna pair is greater than 63, by setting the delay indication field and a byte in the effective path indication field corresponding to 8 paths, more paths can be sent to the field position of the sending end, so that the sending end can obtain delay information on all effective paths between the antenna pair, and therefore, the embodiment of the invention is not limited by one antenna in 802.11ad supporting 63 channel taps at most, and the feedback efficiency and the feedback flexibility of the receiving end are greatly improved.

In a possible design, before the receiving end sends a time domain CSI encapsulation packet to the transmitting end according to the time domain CSI between each antenna pair, the method further includes:

the receiving end receives third indication information sent by the sending end, wherein the third indication information is used for indicating the number of sending antennas to the receiving end;

and the receiving end judges whether to perform time domain CSI feedback according to the number of the transmitting antennas and the number of the receiving antennas.

According to the method provided by the possible design, whether the receiving end needs to perform time domain CSI feedback is judged according to the number of the transmitting antennas and the number of the receiving antennas, so that the receiving end can be prevented from blindly determining a time domain CSI encapsulation packet, and the processing overhead of the receiving end is greatly saved.

In a second aspect, an embodiment of the present invention provides an apparatus for feeding back channel state information, including: the acquisition module is used for acquiring time domain Channel State Information (CSI) between each antenna pair;

the sending module is used for sending a time domain CSI encapsulation packet to a sending end according to the time domain CSI between each antenna pair; the time domain CSI encapsulation packet is used for indicating the field position where each effective path between each antenna pair is located and the effective path gain information of the path corresponding to each antenna pair to the transmitting end; the field position of the effective diameter is used for indicating the sending end to determine the time delay information of the effective diameter according to the field position of the effective diameter and the preset unit time delay; the effective path is a path of which the gain is greater than a preset gain threshold in the path.

In one possible design, the time-domain CSI encapsulation packet includes a delay indication field, an effective path indication field, and an effective path gain indication field; the time delay indication field is used for representing a byte number of a last effective path between any antenna pair corresponding to the effective path indication field; each byte in the effective diameter indication field corresponds to 8 diameters, and the effective diameter indication field is used for indicating the field position of each effective diameter between the antenna pairs to the sending end so that the sending end can obtain the time delay information of the effective diameter according to the field position of the effective diameter and the unit time delay; the effective path gain indication field is used for indicating effective path gain quantization information of each antenna pair corresponding path to the transmitting end.

In a possible design, the sending module specifically includes:

a first determining unit, configured to determine a time-domain MIMO channel matrix according to the time-domain CSI between the antenna pairs, where the time-domain MIMO channel matrix includes a channel impulse response of at least one path, and one path includes at least one path;

a first encoding unit, configured to encode, in bytes, a path on each path in the time-domain MIMO channel matrix, and obtain, according to the encoded path, a bit array corresponding to each path, a byte number L of a last effective path on each path corresponding to the bit array, and a number P of the effective paths on each path; wherein each bit of the bit array corresponds to a path on the path;

a second encoding unit, configured to perform binary encoding on the L corresponding to each path, and use the encoded L corresponding to each path as a delay indication field of each path;

a deleting unit, configured to delete, according to the L corresponding to each path, a bit located after the L in the bit array corresponding to each path to obtain a new bit array, and use the new bit array as an effective path indication field of each path;

a quantization unit, configured to obtain effective path gain quantization information of each path according to the number P of effective paths in each path and gain information obtained by quantizing each effective path in each path, and use the effective path gain quantization information as an effective path gain indication field of each path;

a second determining unit, configured to determine the time-domain CSI encapsulation packet according to the delay indication field of each path, the effective path indication field of each path, and the effective path gain indication field of each path;

and the sending unit is used for sending the time domain CSI encapsulation packet to the sending end.

In a possible design, the first determining unit is specifically configured to number the transmitting antennas and the receiving antennas respectively, and obtain channel impulse responses between antenna pairs formed by each transmitting antenna and each receiving antenna in sequence according to the numbers of the transmitting antennas and the numbers of the receiving antennas, and further obtain the time-domain MIMO channel matrix according to the channel impulse responses between the antenna pairs.

In a possible design, the first determining unit is specifically configured to receive at least one first beam optimization protocol BRP frame sent by the sending end, and acquire a TRN field in each first BRP frame; and measuring the channel impulse response between each antenna pair according to each TRN domain, and determining the time domain MIMO channel matrix according to the measurement sequence of each TRN domain and the channel impulse response between each antenna pair.

In a possible design, the sending unit is further configured to send the permutation sequence of the channel impulse responses in the time-domain MIMO channel matrix to the sending end.

In a possible design, the second determining unit is specifically configured to encapsulate a delay indication field, an effective path indication field, and an effective path gain indication field of the same path into a time domain CSI encapsulation packet corresponding to the path; the sending unit is specifically configured to send the time domain CSI encapsulation packet corresponding to each path to the sending end according to the arrangement order of the channel impulse responses in the time domain MIMO channel matrix.

In a possible design, the second determining unit is specifically configured to encapsulate the delay indicator field, the effective diameter indicator field, and the effective diameter gain indicator field corresponding to each path into a time-domain CSI encapsulation sub-packet, encapsulate each time-domain CSI encapsulation sub-packet into the time-domain CSI encapsulation packet according to an arrangement sequence of each channel impulse response in the time-domain MIMO channel matrix, and further send the time-domain CSI encapsulation sub-packet to the sending end through the sending unit 117.

In a possible design, the second determining unit is further configured to perform coding modulation processing on the time-domain CSI encapsulation packet to obtain a modulated CSI encapsulation packet; the sending unit is specifically configured to send the modulated CSI encapsulation packet to the sending end by being carried in a second BRP frame.

In a possible design, the apparatus further includes a receiving module and a determining module;

a receiving module, configured to receive third indication information sent by the sending end, where the third indication information is used to indicate the number of sending antennas to the receiving end;

and the judging module is used for judging whether to perform time domain CSI feedback according to the number of the transmitting antennas and the number of the receiving antennas.

The beneficial effects of the feedback apparatus of channel state information provided by the second aspect and the possible designs of the second aspect may refer to the beneficial effects brought by the first aspect and the possible designs of the first aspect, and are not described herein again.

In a third aspect, an embodiment of the present invention provides a communication device, including:

the processor is used for acquiring time domain Channel State Information (CSI) between each antenna pair;

the transmitter is used for transmitting a time domain CSI encapsulation packet to the transmitting end according to the time domain CSI between each antenna pair; the time domain CSI encapsulation packet is used for indicating the field position where each effective path between each antenna pair is located and the effective path gain information of the path corresponding to each antenna pair to the transmitting end; the field position of the effective diameter is used for indicating the sending end to determine the time delay information of the effective diameter according to the field position of the effective diameter and the preset unit time delay; the effective path is a path of which the gain is greater than a preset gain threshold in the path.

In a possible design, the processor is further configured to determine a time-domain MIMO channel matrix according to the time-domain CSI between each antenna pair, encode a path on each path in the time-domain MIMO channel matrix in bytes, and obtain, according to the encoded path, a bit array corresponding to each path, a byte number L of a last effective path on each path corresponding to the bit array, and a number P of effective paths on each path; binary coding is carried out on the L corresponding to each path, the coded L corresponding to each path is used as a time delay indication field of each path, bit positions behind the L in the bit number group corresponding to each path are deleted according to the L corresponding to each path, a new bit array is obtained, and the new bit array is used as an effective path indication field of each path; obtaining the gain quantization information of the effective diameter of each path according to the number P of the effective diameters on each path and the gain information after the quantization of each effective diameter on each path, and using the gain quantization information of the effective diameter as an effective diameter gain indication field of each path; determining the time domain CSI encapsulation packet according to the delay indication field of each path, the effective path indication field of each path and the effective path gain indication field of each path, and sending the time domain CSI encapsulation packet to the sending end through the sender;

wherein, the time domain MIMO channel matrix comprises the channel impulse response of at least one path, and one path comprises at least one path; each bit of the bit array corresponds to a path on the path.

In one possible design, the determining, by the processor, a time-domain MIMO channel matrix according to the time-domain CSI between the antenna pairs specifically includes:

the processor is specifically configured to number the transmitting antennas and the receiving antennas respectively, obtain channel impulse responses between antenna pairs formed by each transmitting antenna and each receiving antenna in sequence according to the numbers of the transmitting antennas and the numbers of the receiving antennas, and obtain the time-domain MIMO channel matrix according to the channel impulse responses between the antenna pairs.

In one possible design, the communication device further includes a receiver;

the receiver is configured to receive at least one first beam optimization protocol BRP frame sent by the sending end;

the processor is specifically configured to acquire a TRN domain in each first BRP frame, measure a channel impulse response between each antenna pair according to each TRN domain, and determine the time-domain MIMO channel matrix according to a measurement order of each TRN domain and the channel impulse response between each antenna pair.

In one possible design, the transmitter is further configured to, after the processor determines a time-domain MIMO channel matrix according to the time-domain CSI between each antenna pair, send an arrangement order of each channel impulse response in the time-domain MIMO channel matrix to the transmitting end.

In one possible design, the processor is specifically configured to encapsulate a delay indication field, an effective path indication field, and an effective path gain indication field of the same path into a time domain CSI encapsulation packet corresponding to the path;

the transmitter is specifically configured to send the time domain CSI encapsulation packet corresponding to each path to the sending end according to the arrangement order of the channel impulse responses in the time domain MIMO channel matrix.

In a possible design, the processor is specifically configured to encapsulate a delay indication field, an effective path indication field, and an effective path gain indication field corresponding to each path into a time-domain CSI encapsulation sub-packet, encapsulate each time-domain CSI encapsulation sub-packet into the time-domain CSI encapsulation packet according to an arrangement sequence of channel impulse responses in the time-domain MIMO channel matrix, and further send the time-domain CSI encapsulation packet to the sending end through the sender.

In a possible design, the processor is further configured to perform coding modulation processing on the time-domain CSI encapsulation packet to obtain a modulated CSI encapsulation packet;

the transmitter is specifically configured to send the modulated CSI encapsulation packet to the sending end by being carried in a second BRP frame.

In a possible design, the receiver is further configured to receive third indication information sent by the sending end before the sender sends a time domain CSI encapsulation packet to the sending end according to the time domain CSI between each antenna pair, where the third indication information is used to indicate the number of sending antennas to the receiving end;

the processor is further configured to determine whether to perform time-domain CSI feedback according to the number of the transmitting antennas and the number of the receiving antennas.

The beneficial effects of the communication device provided by the possible designs of the third aspect and the third aspect may refer to the beneficial effects brought by the possible designs of the first aspect and the first aspect, and are not described herein again.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

Fig. 1 is a schematic structural diagram of a WLAN system according to an embodiment of the present invention;

fig. 2 is a schematic flowchart of a first embodiment of a method for feeding back channel state information according to an embodiment of the present invention;

fig. 3 is a first schematic structural diagram of a time-domain CSI encapsulation packet according to an embodiment of the present invention;

fig. 4 is a schematic structural diagram of a time-domain CSI encapsulation packet according to an embodiment of the present invention;

fig. 5 is a flowchart illustrating a second method for feeding back channel state information according to an embodiment of the present invention;

fig. 6 is a first schematic flowchart of obtaining a time domain MIMO channel matrix according to an embodiment of the present invention;

fig. 7 is a schematic flowchart of a second process for obtaining a time-domain MIMO channel matrix according to an embodiment of the present invention;

FIG. 8 is a schematic diagram of a variation of a bit array according to an embodiment of the present invention;

FIG. 9 is a diagram of a new bit array according to an embodiment of the present invention;

fig. 10 is a first flowchart illustrating a process of determining and sending a time domain CSI encapsulation packet by a receiving end according to an embodiment of the present invention;

fig. 11 is a second schematic flowchart of a process of determining and sending a time domain CSI encapsulation packet by a receiving end according to an embodiment of the present invention;

fig. 12 is a schematic structural diagram three of a time-domain CSI encapsulation packet according to an embodiment of the present invention;

fig. 13 is a schematic structural diagram of a time-domain CSI encapsulation packet according to an embodiment of the present invention;

fig. 14 is a schematic structural diagram of a first embodiment of a feedback apparatus for csi according to an embodiment of the present invention;

fig. 15 is a schematic structural diagram of a second feedback apparatus for csi according to an embodiment of the present invention;

fig. 16 is a schematic structural diagram of an embodiment of a communication device according to an embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The feedback method of the channel state information related to the embodiment of the invention can be suitable for Wireless Local Area Networks (WLAN for short) and can also be suitable for Frequency Division duplex Long Term Evolution (FDD-LTE) systems. Taking a WLAN network as an example, the standard adopted by the WLAN at present is the Institute of Electrical and Electronics Engineers (IEEE for short) 802.11 series, that is, the method related to the embodiment of the present invention may be applicable to an IEEE802.11n/ac system, an IEEE802.11ad system, an IEEE802.11ay system, and the IEEE802.11ay system, which adopts channel convergence, MIMO and other technologies. The Station (STA) and the Access Point (AP) are basic components of the WLAN.

The AP is an access point for a mobile subscriber to enter a wired network, and is mainly deployed in a home, a building, and a campus, and typically has a coverage radius of several tens of meters to hundreds of meters, and may be deployed outdoors. The AP acts as a bridge connecting the network and the wireless network, and mainly functions to connect the wireless network clients together and then to access the wireless network to the ethernet. Specifically, the AP may be a terminal device or a network device with a WiFi (Wireless Fidelity, chinese) chip. Optionally, the AP may be a device supporting 802.11ax systems, further optionally, the AP may be a device supporting multiple WLAN systems such as 802.11ac, 802.11n, 802.11g, 802.11b, and 802.11a, and in this embodiment, the AP may also be a device supporting WLAN systems such as 802.11ad and 802.11 ay. Alternatively, the AP in the embodiment of the present invention may also be replaced with a Personal Service Set Control Point (PCP), and the PCP may also communicate with multiple STAs.

STAs are typically client devices in a WLAN. The STA may be mobile or fixed, and is the most basic component unit of the wireless local area network, and may be a wireless communication chip, a wireless sensor or a wireless communication terminal. For example: the mobile phone supporting the WiFi communication function, the tablet computer supporting the WiFi communication function, the set top box supporting the WiFi communication function, the smart television supporting the WiFi communication function, the smart wearable device supporting the WiFi communication function, the vehicle-mounted communication device supporting the WiFi communication function and the computer supporting the WiFi communication function.

The sending end related to the embodiment of the invention can be an AP, an STA, other communication equipment, and a receiving end, wherein the receiving end can be the AP, the STA or other communication equipment. In short, the embodiments of the present invention do not limit the specific forms of the sending end and the receiving end.

As shown in fig. 1, taking 802.11ay as an example in a WLAN network, the network includes a transmitting end, a receiving end and a reflecting object, the transmitting end includes a plurality of transmitting antennas, the receiving end includes a plurality of receiving antennas, the reflecting object reflects different types of objects according to different scenes, for example, if the scene is an indoor scene, the reflecting object may be a wall, an ornament, etc., and if the scene is an outdoor scene, the reflecting object may be a building, a vehicle, a pedestrian, etc. The transmitting end and the receiving end in fig. 1 use MIMO technology for data transmission. It should be noted that the antenna pair according to the embodiment of the present invention may include a transmitting antenna at a transmitting end and a receiving antenna at a receiving end, where the antenna pair corresponds to a path, and starting from a frequency domain, the path includes multiple subcarriers, and each subcarrier is a frequency domain channel; if a path includes multiple paths from the time domain, there are straight propagation paths and other transmission paths (i.e. multipath propagation).

The CSI feedback method provided by the embodiment of the invention mainly aims at the problem of how to save feedback overhead in the process of estimating the CSI by a receiving end and feeding the CSI back to a transmitting end. In the prior art, in the process of performing CSI feedback on CSI, two feedback modes are included, namely frequency-domain CSI feedback and time-domain CSI feedback, where a receiving end in the frequency-domain CSI feedback mode feeds back gain information on each subcarrier, and a receiving end in the time-domain CSI feedback mode feeds back gain information and delay information on each path, where the delay information refers to transmission delay of one path relative to a path of linear propagation, and the number of multipaths between one antenna pair is much smaller than the number of subcarriers between the antenna pair, so that the time-domain CS feedback mode has a smaller overhead than the frequency-domain CSI feedback mode. For an 802.11n/ac system, the channel estimation module estimates the channel gain on each subcarrier, and the CSI feeds back frequency domain CSI information, because the number of subcarriers in the 802.11n/ac system is small and the frequency domain feedback overhead is not large, but ieee802.11ay adopts the techniques of channel aggregation, MIMO and the like, and has more subcarriers, the frequency domain CSI feedback brings great overhead, so the frequency domain feedback scheme is not suitable for the ieee802.11ay system; on the other hand, the time-domain CSI feedback is adopted in the ieee802.11ad system, which quantizes the delay information of all taps and feeds back the delay information, and if the 11ay system adopts the time-domain CSI feedback method, since the 11ay system adopts the techniques of channel aggregation, MIMO and the like, the number of channel taps is large, the delay information of all the channel taps needs to be quantized and fed back, the feedback delay cost is large, and the current time-domain CSI feedback scheme can only support the feedback of the delay information of 63 taps at most.

Therefore, the method and the device for feeding back the channel state information provided by the embodiment of the invention aim to solve the technical problem that the CSI feedback scheme in the prior art cannot be applied to the IEEE802.11ay system, that is, the time delay feedback overhead of the CSI cannot be reduced.

The technical solution of the present invention will be described in detail below with specific examples. The following several specific embodiments may be combined with each other, and details of the same or similar concepts or processes may not be repeated in some embodiments.

Fig. 2 is a flowchart illustrating a first embodiment of a method for feeding back channel state information according to an embodiment of the present invention. The embodiment relates to a specific process that a receiving end sends a time domain CSI encapsulation packet to a sending end through the obtained time domain CSI of each antenna pair between the sending end and the receiving end so as to reduce the time delay feedback overhead through the time domain CSI encapsulation packet. As shown in fig. 2, the method comprises the steps of:

s101: and the receiving end acquires the time domain CSI between each antenna pair.

Specifically, because a channel estimation domain (CEF) in the ieee802.11ay system adopts single carrier transmission, a receiving end correspondingly obtains time domain CSI between each antenna pair in the ieee802.11ay system, which may specifically refer to the description of the prior art and is not described herein again. The time-domain CSI of an antenna pair includes delay information of each path between the antenna pair and gain information on each path, and actually, the time-domain CSI of an antenna pair is a channel impulse response corresponding to the antenna pair, where the channel impulse response is a row vector and includes delays of multiple paths and gains of multiple paths.

S102: and the receiving end sends a time domain CSI encapsulation packet to the sending end according to the time domain CSI between each antenna pair.

The time domain CSI encapsulation packet is used for indicating the field position where each effective path between each antenna pair is located and the effective path gain information of the path corresponding to each antenna pair to the transmitting end; the field position of the effective diameter is used for indicating the sending end to determine the time delay information of the effective diameter according to the field position of the effective diameter and the preset unit time delay; the effective path is a path of which the gain is greater than a preset gain threshold in the path.

Specifically, after the receiving end obtains the time domain CSI between each antenna pair, a time domain CSI encapsulation packet is generated according to the time domain CSI, and a specific generation method is not limited in the embodiments of the present invention, as long as the generated time domain CSI encapsulation packet can indicate, to the transmitting end, a field position where each effective path between each antenna pair is located and effective path gain information of a path corresponding to each antenna pair. The effective path refers to a path with a gain larger than a preset gain threshold, and a path with a gain smaller than or equal to the preset gain threshold is called an ineffective path. Optionally, the time-domain CSI encapsulation packet may be an encapsulation packet sent by one antenna pair, where the receiving end sends the time-domain CSI encapsulation packet corresponding to each antenna pair to the sending end one by one, where the time-domain CSI encapsulation packet indicates a field position where each effective diameter of the antenna pair is located, and it needs to be noted that the field position is a relative position of the effective diameter with respect to a diameter linearly propagated between the antenna pairs. Optionally, the time domain CSI encapsulation packet HIA may be a time domain CSI encapsulation packet formed by combining time domain CSI encapsulation sub-packets of a plurality of antenna pairs together, and the embodiment of the present invention does not limit the form in which the receiving end sends the time domain CSI encapsulation packet to the sending end.

S103: and the sending end obtains the field position of each effective diameter according to the time domain CSI encapsulation packet, and determines the time delay information of each effective diameter according to the field position of each effective diameter and the preset unit time delay.

Specifically, after the sending end receives a time domain CSI encapsulation packet sent by the receiving end, the sending end analyzes the time domain CSI encapsulation packet, optionally, if the time domain CSI encapsulation packet is for one antenna pair, that is, the receiving end sends the time domain CSI encapsulation packet to the sending end one by one, because the sending end can know in advance the sequence of the antenna pairs targeted by the receiving end when sending the time domain CSI encapsulation packet, the sending end can know which antenna pair the currently received time domain CSI encapsulation packet is for. Based on this, the transmitting end may perform correct analysis to obtain a field position where each effective diameter between the antenna pair is located, and then determine the delay information of each effective diameter according to the field position where each effective diameter is located and the preset unit delay, for example, assuming that the field position of the effective diameter a relative to a straight propagation path between the antenna pair is 8 and the preset unit delay is 8us, the transmitting end may determine that the delay of the effective diameter a is 64 us. Optionally, if the time-domain CSI encapsulation packet is for multiple antenna pairs, that is, the receiving end uniformly sends the time-domain CSI information of all antenna pairs to the transmitting end, because the transmitting end can know in advance the encapsulation sequence when the receiving end encapsulates multiple time-domain CSI encapsulation sub-packets into one time-domain CSI encapsulation packet, the transmitting end can know which antenna pair each time-domain CSI encapsulation sub-packet in the currently received time-domain CSI encapsulation packet is for, based on this, the transmitting end can perform correct analysis to obtain the field position of each effective diameter between each antenna pair, and then determine the delay information of each effective diameter according to the field position of each effective diameter and the preset unit delay.

As can be seen from the above description, the receiving end only needs to inform the transmitting end of the field position of each effective path between each antenna pair in the time domain CSI encapsulation packet, and the transmitting end can obtain the delay information of each effective path without quantizing the delay information of all effective paths between each antenna pair and feeding back the quantized delay information to the transmitting end, thereby greatly saving the delay feedback overhead of the receiving end.

According to the feedback method of the channel state information provided by the embodiment of the invention, the time domain CSI between each antenna pair is obtained through the receiving end, and the time domain CSI encapsulation packet is sent to the sending end according to the time domain CSI between each antenna pair, so that the sending end can obtain the field position of the effective diameter between each antenna pair according to the time domain CSI encapsulation packet, and further determine the time delay information of the effective diameter according to the field position of the effective diameter and the preset unit time delay.

Further, an embodiment of the present invention relates to a possible implementation manner of the time domain CSI encapsulation packet. In the second embodiment of the present invention, the time-domain CSI encapsulation packet may include a delay indication field, an effective path indication field, and an effective path gain indication field, which may be referred to as a structural schematic diagram of the time-domain CSI encapsulation packet shown in fig. 3, it should be noted that fig. 3 is only an example, and the present invention is not limited thereto.

The time delay indication field is used for representing a byte number of a last effective path between any antenna pair corresponding to the effective path indication field; each byte in the effective diameter indication field corresponds to 8 diameters, and the effective diameter indication field is used for indicating the field position of each effective diameter between the antenna pairs to the sending end so that the sending end can obtain the time delay information of the effective diameter according to the field position of the effective diameter and the unit time delay; the effective path gain indication field information is used for indicating effective path gain quantization information of each antenna pair corresponding path to the transmitting end.

Specifically, in the time domain CSI encapsulation packet, the delay indication field is located before the effective path indication field, and the effective path gain indication field is located before the effective path indication field. The delay indication field in this embodiment may be an 8-bit indication field, or may be more or fewer bit indication fields. The sending end can calculate a decimal value according to the binary bit of the time delay indicating field, and the value corresponds to the byte number of the last effective path between an antenna pair corresponding to the effective path indicating field; for example, assuming that the delay indication field is an 8-bit indication field of 00001000, and the decimal value thereof is 8, the last effective path between the antenna pair corresponding to the delay indication field is located on the byte with the byte number of 8 in the effective path indication field.

In the effective path indication field in fig. 3, one byte corresponds to 8 bits, and one bit corresponds to one path, that is, each byte in the effective path indication field corresponds to 8 paths, the effective path indication field is used to indicate, to the transmitting end, a field position where each effective path between one antenna pair is located, and the field position may specifically be which bit on which byte is located. It should be noted that, a straight propagation path between an antenna pair is located at the first bit on the effective path indication field, so the field position of the effective path indicated by the effective path indication field is the bit position of the effective path relative to the first bit, for example, the last effective path between an antenna pair (the antenna pair is TR1) is continuously indicated according to the delay indication field 00001000, which is located on the 8 th byte on the effective path indication field, and assuming that the last effective path is located on the 6 th bit of the 8 th byte, the field position of the last effective path is 48, the transmitting end may determine the delay information of the last effective path according to the field position and the preset unit delay, and of course, for calculating the effective paths corresponding to other bits in the effective path indication field, the delay information may also be obtained in the same manner, this is only exemplified by the last effective path.

As can be seen from the description of the delay indication field and the effective path indication field, if the delay indication field is a field including n bits, the delay indication field may indicate 2ⁿByte number, and since one byte number corresponds to 8 paths in the effective path indication field, the delay indication field can indicate (2)ⁿMultiplying by 8) paths, namely, by adopting the coding mode, the receiving end can indicate more paths by using fewer bits, so that the receiving end can indicate the field positions where more effective paths are located to the transmitting end, and further the transmitting end can obtain time delay information on the effective paths between all antenna pairs, therefore, the embodiment of the invention can not be limited by supporting 63 channel taps at most in 802.11, and the feedback efficiency and the feedback flexibility of the receiving end are greatly improved.

Further, for the effective path gain indication field located after the effective path indication field, it is used to indicate the effective path gain quantization information of each antenna pair corresponding to the path to the transmitting end. Assuming that the number of effective paths in a path is P, assuming that the quantization bit is Nb, the quantized size of each effective path gain is 2 × Nb, the quantized gain of the path is P × 2 × Nb, and the quantized gain is converted into a binary bit and stored as effective path gain quantization information in an effective path gain indication field. In time-domain CSI feedback, not only the delay information of each effective path between each antenna pair needs to be fed back, but also the effective path gain quantization information of each antenna pair needs to be fed back, so that the sending end can obtain the gain of each antenna after quantizing the corresponding path according to the effective path gain indication field in the CSI encapsulation packet, thereby providing a good power reference for data transmission performed again by the sending end.

Further, on the basis of the second embodiment, as a possible implementation manner of the second embodiment, the delay indication field in the implementation manner is an 8-bit indication field, and the delay indication field may also be used to characterize the length of the effective path indication field, which may specifically refer to the structural diagram of the CSI encapsulation packet shown in fig. 4.

Specifically, in order to better describe the structure and field meaning of the CSI encapsulation packet, a path of one antenna pair (let the antenna pair be TR1) is taken as an example in this embodiment: the delay Indication field is set as a CSI Feedback Offset subfield field, the effective diameter Indication field is set as a CSI Feedback Indication Map subfield field, and the effective diameter gain Indication field is set as a CSI Information subfield.

As shown in fig. 4, the delay indication field corresponding to the path of TR1 is assumed to be 00001000, and the main function of the delay indication field is to indicate that the last effective path corresponds to the byte number on the effective path indication field⁸And the byte number is the number, so that the 8-bit delay indication can indicate 2048 paths at most, the requirement of an 11ay system is met, and the backward compatibility of the system is fully considered.

When the delay indication field indicates the byte number of the last effective path, and is set to L, the length of the effective path indication field may be (L × 8) bits, that is, the value of the delay indication field may indicate the length of the effective path indication field. After the sending end obtains the delay indication field, the length of the effective path indication field behind the delay indication field can be obtained, and therefore the sending end can conveniently decode the frame.

According to the feedback method of the channel state information, provided by the embodiment of the invention, the field position of each effective diameter between each antenna pair is represented to the sending end by adopting different fields, so that the sending end can obtain the time delay information of the effective diameter between each antenna pair according to the field position of each effective diameter, and the time delay information of all the effective diameters between each antenna pair is not required to be quantized and fed back to the sending end by the receiving end, so that the time delay feedback overhead of the receiving end is greatly saved; on the other hand, when the number of paths between an antenna pair is greater than 63, more paths can be located at field positions to the transmitting end through the setting of 8 paths corresponding to one byte in the delay indication field and the effective path indication field, so that the transmitting end can obtain delay information on all effective paths between the antenna pair.

Fig. 5 is a flowchart illustrating a second method for feeding back channel state information according to an embodiment of the present invention. The embodiment relates to a specific process that a receiving end generates the time domain CSI encapsulation packet according to the time domain CSI between each antenna pair and sends the time domain CSI encapsulation packet to a sending end. On the basis of the foregoing embodiment, further, the foregoing S102 may specifically include:

s201: and the receiving end determines a time domain MIMO channel matrix according to the time domain CSI between each antenna pair.

Wherein, the time domain MIMO channel matrix comprises the channel impulse response of at least one path, and one path comprises at least one path.

Specifically, after acquiring the time domain CSI between each antenna pair, the receiving end may determine a time domain MIMO channel matrix according to the time domain CSI, where the time domain MIMO channel matrix includes a channel impulse response of at least one path (one antenna pair corresponds to one path), and one path may include at least one path. Optionally, after the receiving end determines the time-domain MIMO channel matrix according to the time-domain CSI between each antenna pair, the receiving end may further send the permutation sequence of each channel impulse response in the time-domain MIMO channel matrix to the sending end, so that the sending end can correctly analyze the time-domain CSI encapsulation packet sent by the receiving end according to the permutation sequence.

Optionally, the receiving end may determine the time domain MIMO channel matrix according to the time domain CSI between each antenna pair in two ways, which are:

the first implementation mode comprises the following steps: referring to a first flowchart of obtaining a time-domain MIMO channel matrix shown in fig. 6, as shown in fig. 6, the implementation specifically includes:

s301: and the receiving end numbers the sending antenna and the receiving antenna respectively.

Optionally, the receiving end may number the multiple transmitting antennas of the transmitting end as {1, 2, … … Nt }, and number the multiple receiving antennas of the receiving end as {1, 2, … … Nr }, which is only an example, and the manner in which the transmitting antennas and the receiving antennas are numbered in the embodiment of the present invention is not limited.

S302: and the receiving end sequentially obtains the channel impulse response between the antenna pair formed by each transmitting antenna and each receiving antenna according to the serial number of the transmitting antenna and the serial number of the receiving antenna.

S303: and the receiving end acquires the time domain MIMO channel matrix according to the channel impulse response between each antenna pair.

Specifically, the receiving end may fix the transmitting antenna i (i starts from 1), arrange the channel impulse responses between the transmitting antenna i and each receiving antenna according to the serial numbers, then obtain the channel impulse responses between the i +1 transmitting antenna and each receiving antenna according to the serial numbers for i +1, and repeat this process until obtaining the channel impulse response between the antenna pair formed by each transmitting antenna and each receiving antenna, where the channel impulse response between each antenna pair is a row vector, and includes the delay information of each path between the antenna pairs and the gain of each path. Based on this, after obtaining the channel impulse response between each antenna pair, the receiving end can obtain the time domain MIMO channel matrix.

The second implementation mode comprises the following steps: referring to fig. 7, a second flowchart of obtaining a time-domain MIMO channel matrix is shown, and as shown in fig. 7, the implementation specifically includes:

s401: and the receiving end receives at least one first Beam optimization protocol (BRP) frame sent by the sending end.

S402: and the receiving end acquires a Training (TRN) field in each first BRP frame.

Specifically, the transmitting end may specifically include multiple transmitting antennas, and the transmitting end may transmit at least one first BRP frame to the receiving end through each transmitting antenna, and specifically, the transmitting end may specifically adopt all transmitting antennas for transmission or a part of transmitting antennas for transmission, which may be determined by a transmitting mechanism of the transmitting end. When the receiving end receives at least one first BRP frame sent by the sending end, the receiving end analyzes each first BRP frame to obtain the TRN domain in each first BRP frame, and the specific analysis mode may refer to the prior art and is not described herein again.

S403: and the receiving end measures the channel impulse response between each antenna pair according to each TRN domain, and determines the time domain MIMO channel matrix according to the measurement sequence of each TRN domain and the channel impulse response between each antenna pair.

Specifically, after analyzing the TRN field in each first BRP frame, the receiving end may obtain, according to the TRN field, which transmitting antenna of the first BRP frame carrying the TRN field transmits, and also obtain which receiving antenna receives the first BRP frame, that is, obtain the antenna pair corresponding to the TRN field. It should be noted that, the receiving end measures the channel impulse responses between the antenna pairs corresponding to the TRN domain one by one according to the TRN domain, so that the receiving end can determine the arrangement order of the channel impulse responses between each antenna pair in the time-domain MIMO channel matrix according to the measurement order of each TRN domain and the channel impulse response between each antenna pair, thereby obtaining the time-domain MIMO channel matrix.

S202: and the receiving end encodes the path on each path in the time domain MIMO channel matrix according to bytes, and acquires a bit array corresponding to each path, a byte number L corresponding to the last effective path on each path on the bit array and the number P of the effective paths on each path according to the encoded path.

Wherein each bit of the bit array corresponds to a path on the path.

Specifically, after obtaining the time-domain MIMO channel matrix, the receiving end encodes the path on each path (one path corresponding to one channel impulse response) in the time-domain MIMO channel matrix by byte, that is, numbering from 1, where each 8 paths are one byte, and then obtains a bit array corresponding to each path according to the encoded path, where the number of bits in the bit array is related to the number of bytes obtained by the encoded path, that is, the number of bytes obtained by the encoded path is equal to the number of bytes obtained by multiplying 8. Assuming that a path includes 16 paths, the path corresponds to 2 bytes, and the corresponding bit array is a 16-bit array, where each bit corresponds to one path in the path.

Further, the receiving end determines the effective path in each path, and when the effective path corresponds to the bit array, the bit position 1 corresponding to the effective path and the bit position 0 corresponding to the ineffective path are located, and the receiving end also obtains the byte number L corresponding to the bit array of the last effective path in each path and the total number P of the effective paths in each path. For example, referring to the schematic diagram of the change of the bit array shown in fig. 8, taking a path as an example, the receiving end obtains the bit array corresponding to the path according to the path coded by the path, where a is a, each bit (i.e., a small box in a) corresponds to one path on the path, after the receiving end determines the effective path in the path, the receiving end determines bit position 1 corresponding to the effective path in the bit array, and bit position 0 corresponding to the ineffective path in the bit array, where the first bit in the bit array is a straight-line propagation path in the path, so as to obtain b in fig. 8; as can be seen from b, the last effective path is located in the byte with byte number 8, and the bits in the bytes after byte number 8 are all 0.

S203: and the receiving end performs binary coding on the L corresponding to each path, and takes the coded L corresponding to each path as a time delay indication field of each path.

Specifically, after the receiving end obtains the byte number L of the last effective path in each path in the bit array, binary coding is performed on the L, and the coded L is used as the delay indication field of each path. For example, continuing with the above example, if L is 8, the delay indication field corresponding to the path is 00001000.

S204: and the receiving end deletes the bit position behind the L in the bit number group corresponding to each path according to the L corresponding to each path to obtain a new bit array, and uses the new bit array as the effective path indicating field of each path.

Specifically, after the receiving end obtains L in each path, it is determined that the byte position where the last effective path is located is the byte with the byte number L, that is, the paths located on the bytes after L are all the invalid paths, therefore, in order to further save the feedback overhead, the receiving end deletes all the bits after L to obtain a new bit array, and further uses the new bit array as the effective path indication field of each path, for example, refer to the example of fig. 8 continuously, and the finally obtained new bit array c refers to fig. 9, where the new bit array is the effective path indication field of the path.

S205: and the receiving end acquires the gain quantization information of the effective diameter of each path according to the number P of the effective diameters on each path and the gain information after the quantization of each effective diameter on each path, and uses the gain quantization information of the effective diameter as an effective diameter gain indication field of each path.

Specifically, the effective path gain of one path is a complex number, and the receiving end quantizes the real part and the imaginary part of the path respectively. Assuming that the quantization bit widths of the real part and the imaginary part of the effective path gain are both Nb bits, wherein Nb is 1+ m, 1 represents that the corresponding channel gain is positive, and 0 represents that the corresponding channel gain is negative; m is a bit decimal place, and the decimal place bit width is determined according to the precoding requirement of a digital domain of a sending end; the quantization precision of the quantization scheme may be used as the preset gain threshold.

Therefore, the receiving end obtains the total number P of the effective paths on each path according to the quantization precision, and when the quantization bit is Nb, the quantized gain of the path is P × 2 × Nb, converts the quantized gain into a binary bit, and then uses the binary bit as the effective path gain quantization information of the path, and uses the effective path gain quantization information as the effective path gain indication field of the path.

S206: and the receiving end determines the time domain CSI encapsulation packet according to the time delay indication field of each path, the effective path indication field of each path and the effective path gain indication field of each path, and sends the time domain CSI encapsulation packet to the sending end.

Optionally, the receiving end determines the time domain CSI encapsulation packet according to the delay indication field, the effective path indication field, and the effective path gain indication field of each path obtained in S203, S204, and S205, and sends the time domain CSI encapsulation packet to the sending end, which may specifically include two possible implementation manners:

a first possible implementation: referring to fig. 10, a first flow diagram of determining and sending a time domain CSI encapsulation packet by a receiving end is shown, where the method includes:

s501: and the receiving end packages the time delay indication field, the effective path indication field and the effective path gain indication field of the same path into a time domain CSI package packet corresponding to the path.

S502: and the receiving end respectively sends the time domain CSI encapsulation packet corresponding to each path to the sending end according to the arrangement sequence of the channel impulse responses in the time domain MIMO channel matrix.

Specifically, in this possible implementation manner, the receiving end encapsulates each of the delay indication field, the effective path indication field, and the effective path gain indication field belonging to the same path into a time domain CSI encapsulation packet corresponding to the path, that is, one path corresponds to one CSI encapsulation packet, and the structure of the time domain CSI encapsulation packet is that the delay indication field of the path is in front of the effective path indication field, the effective path indication field is immediately behind the effective path indication field, and the effective path gain indication field is immediately behind the effective path indication field, as shown in fig. 3 and fig. 4. And then the receiving end respectively sends the time domain CSI encapsulation packets corresponding to each path to the sending end according to the arrangement sequence of each channel impulse response in the time domain MIMO channel matrix.

After the receiving end obtains the time-domain MIMO channel matrix, the receiving end sends the sequence of the channel impulse responses in the time-domain MIMO channel matrix to the sending end, so that the sending end can acquire the first channel impulse response in the time-domain MIMO channel matrix corresponding to the time-domain CSI encapsulation packet sent by the receiving end for the first time, and then the sending end can acquire the time delay information of each path and the gain information of each path between the antenna pairs corresponding to the first channel impulse response according to the first time-domain CSI encapsulation packet; similarly, the sending end can acquire a second channel impulse response in the time-domain MIMO channel matrix corresponding to a time-domain CSI encapsulation packet sent by the receiving end for the second time, and then the sending end can acquire delay information of each path and gain information of each path between antenna pairs corresponding to the second channel impulse response according to the second time-domain CSI encapsulation packet; by analogy, the transmitting end can obtain the channel state information between corresponding antenna pairs according to the sequence of the time domain MIMO channel matrix and the time domain CSI encapsulation packet of the receiving end.

A second possible implementation: referring to fig. 11, a second flow chart of determining and sending a time domain CSI encapsulation packet by a receiving end is shown, where the method includes:

s601: and the receiving end packages the delay indication field, the effective path indication field and the effective path gain indication field corresponding to each path into a time domain CSI package sub-package.

S602: and the receiving end packages each time domain CSI package sub-packet into the time domain CSI package packet according to the arrangement sequence of each channel impulse response in the time domain MIMO channel matrix, and sends the time domain CSI package packet to the sending end.

Specifically, the receiving end encapsulates each delay indication field, effective path indication field, and effective path gain indication field belonging to the same path into a time domain CSI encapsulation sub-packet corresponding to the path, that is, one path corresponds to one time domain CSI encapsulation sub-packet, and the structure of the time domain CSI encapsulation sub-packet is that the delay indication field of the path is in front of the effective path indication field, the effective path indication field is immediately behind the effective path indication field, and the effective path gain indication field is immediately behind the effective path indication field, as shown in fig. 3 and 4. And then the receiving end packages each time domain CSI packaging sub-packet into a time domain CSI packaging packet according to the arrangement sequence of each channel impulse response in the time domain MIMO channel matrix, and sends the time domain CSI packaging packet to the sending end, namely, the time domain CSI packaging sub-packet of a path corresponding to the first channel impulse response in the time domain MIMO channel matrix is taken as the first time, then the time domain CSI packaging sub-packet of a path corresponding to the second channel impulse response is taken as the second time immediately after the first time, and so on, thus obtaining the complete time domain CSI packaging packet. For example, assuming that the receiving end totally encapsulates the time-domain CSI encapsulation sub-packet 1 corresponding to h11, the time-domain CSI encapsulation sub-packet 3 corresponding to h12, and the time-domain CSI encapsulation sub-packet 4 corresponding to h22 according to the arrangement order of the time-domain MIMO channel matrix, wherein h11, h12, h21, and h22 are all channel impulse responses in the time-domain MIMO channel matrix, h11 is a vector of a first row and a first column in the time-domain MIMO matrix, h12 is a vector of a first row and a second column in the time-domain MIMO matrix, h21 is a vector of a second row and a first column in the time-domain MIMO matrix, and h22 is a vector of a second row and a second column in the time-domain MIMO matrix, the receiving end encapsulates the time-domain CSI encapsulation sub-packet 1, the time-domain CSI encapsulation sub-packet 2, the time-domain CSI encapsulation sub-packet 3, and the time-domain CSI encapsulation sub-packet 4 into the time-domain CSI packet shown in the above-mentioned order of h11, h 82.

And after the receiving end obtains the time domain CSI encapsulation packet, sending the time domain CSI encapsulation packet to the sending end. After obtaining the time-domain MIMO channel matrix, the receiving end sends the order of the channel impulse responses in the time-domain MIMO channel matrix to the sending end, so that the sending end can know that a first time-domain CSI encapsulation sub-packet in a time-domain CSI encapsulation packet sent by the receiving end corresponds to a first channel impulse response in the time-domain MIMO channel matrix, and then the sending end can know the delay information of each path and the gain information of each path between antenna pairs corresponding to the first channel impulse response according to the first time-domain CSI encapsulation sub-packet; similarly, the sending end can acquire a second channel impulse response in the time-domain MIMO channel matrix corresponding to a second time-domain CSI encapsulation sub-packet in the time-domain CSI encapsulation packet sent by the receiving end, and then the sending end can acquire delay information of each path and gain information of each path between antenna pairs corresponding to the second channel impulse response according to the second time-domain CSI encapsulation sub-packet; by analogy, the sending end can obtain the channel state information between corresponding antenna pairs according to the sequence of the time domain MIMO channel matrix and the received time domain CSI encapsulation packet.

No matter which form the receiving end sends the time domain CSI encapsulation packet to the sending end, optionally, the receiving end may send the time domain CSI encapsulation packet directly, and may also perform coding modulation processing on the time domain CSI encapsulation packet to obtain a modulated CSI encapsulation packet, and send the modulated CSI encapsulation packet to the sending end while carrying the modulated CSI encapsulation packet in the second BRP frame. Optionally, the receiving end may select an error correction coding scheme suitable for the receiving end according to a specific application requirement, for example, a Low Density Parity Check Code (LDPC for short); optionally, when the time domain CSI is coded and modulated, the modulation scheme may adopt a modulation scheme that supports both a low order and a high order, and when the feedback channel is unreliable, the low order scheme is used to ensure the effectiveness, and when the feedback channel is reliable, the high order scheme is used to improve the feedback efficiency, but the embodiment of the present invention is not limited thereto. Optionally, in consideration of system compatibility, the modulated CSI encapsulation packet may be added to a BRP feedback frame (BRP with feedback) of a second BRP frame to obtain an Ex-BRP-FB, which is the second BRP frame carrying the modulated CSI encapsulation packet, as shown in the frame structure diagram shown in fig. 13.

Optionally, when the receiving end carries the modulated CSI encapsulation packet in a second BRP frame and sends the second BRP frame to the sending end, the receiving end may carry first indication information and second indication information in the second BRP frame, optionally, the first indication information and the second indication information may be carried in a DMG Beam update element in the second BRP frame, the first indication information is used to indicate to the sending end that the second BRP frame carries the modulated CSI encapsulation packet, the second indication information is used to indicate to the sending end the number of the effective paths on each path, after the sending end receives the second BRP frame, the sending end may analyze the time domain CSI encapsulation packet according to the first indication information and the second indication information, so as to obtain delay information and gain information of each path between the sending end and the receiving end.

Optionally, before the above S102 or before S201, the method may further include the following steps:

s701: and the receiving end receives third indication information sent by the sending end, wherein the third indication information is used for indicating the number of the sending antennas to the receiving end.

S702: and the receiving end judges whether to perform time domain CSI feedback according to the number of the transmitting antennas and the number of the receiving antennas.

Specifically, when acquiring CSI between each antenna pair, the receiving end may also receive third indication information sent by the sending end, where the third indication information is used to indicate, to the receiving end, the number of sending antennas on the sending end, and optionally, the third indication information may be carried in the first BRP frame. When the receiving end obtains the number of the transmitting antennas on the transmitting end, whether time domain CSI feedback is needed or not is judged according to the number of the transmitting antennas, the number of the receiving antennas, a preset transmitting antenna threshold value and a preset receiving antenna threshold value. When the number of the transmitting antennas is smaller than a preset transmitting antenna threshold, or the number of the receiving antennas is smaller than a preset receiving antenna threshold, it is determined that time domain CSI feedback is not required currently, where the preset transmitting antenna threshold and the receiving antenna threshold are both integers greater than or equal to 1, and the specific threshold setting may be determined according to an actual application situation of the system, for example, if the third indication information indicates a transmitting and receiving antenna of 1 × 1, the receiving end does not need to perform time domain CSI feedback. The method judges whether the receiving end needs to perform time domain CSI feedback according to the number of the transmitting antennas and the number of the receiving antennas, so that the receiving end can be prevented from blindly determining the time domain CSI encapsulation packet, and the processing overhead of the receiving end is greatly saved.

The feedback method of the channel state information provided by the embodiment of the invention determines a time domain MIMO channel matrix according to time domain CSI between each antenna pair through a receiving end, codes the path on each path in the time domain MIMO channel matrix according to bytes, and acquires a bit array corresponding to each path, a byte number L corresponding to the last effective path on each path on the bit array, and the number P of the effective paths on each path according to the coded path; then the receiving end carries out binary coding on the L corresponding to each path, and the coded L corresponding to each path is used as a time delay indication field of each path; deleting the bit position behind the L in the bit number group corresponding to each path according to the L corresponding to each path to obtain a new bit array, and indicating the effective path indicating field of each path in the new bit array; and the receiving end obtains the gain quantization information of the effective diameter of each path according to the number P of the effective diameters on each path and the gain information after the quantization of each effective diameter on each path, and uses the gain quantization information of the effective diameter as the gain indication field of the effective diameter of each path, thereby determining a time domain CSI encapsulation packet and sending the time domain CSI encapsulation packet to the sending end according to the time delay indication field of each path, the effective diameter indication field of each path and the gain indication field of the effective diameter of each path, the time domain CSI encapsulation packet obtained by adopting the method can represent the field position of each effective diameter between each antenna pair to the sending end, so that the sending end can obtain the time delay information of the effective diameter between each antenna pair according to the field position of each effective diameter, and the receiving end does not need to feed back the time delay information of all the effective diameters between each antenna pair to the sending end after the time delay information of each antenna pair, the time delay feedback overhead of a receiving end is greatly saved; on the other hand, the length of the effective path indication field is reduced by deleting the bit representing the ineffective path after L, so that the size of a time domain CSI encapsulation packet is reduced, and the time domain feedback overhead of a receiving end is further reduced; further, when the number of paths between an antenna pair is greater than 63, by setting the delay indication field and a byte in the effective path indication field corresponding to 8 paths, more paths can be sent to the field position of the sending end, so that the sending end can obtain delay information on all effective paths between the antenna pair, and therefore, the embodiment of the invention is not limited by one antenna in 802.11ad supporting 63 channel taps at most, and the feedback efficiency and the feedback flexibility of the receiving end are greatly improved.

To further illustrate that the embodiment of the present invention saves system overhead when performing time-domain CSI feedback, the following is to analyze various system feedback overheads of 802.11 series related to the present solution one by one:

1. feedback overhead for CSI for IEEE802.11n/ac systems

(1) Ieee802.11n system: suppose the number of subcarriers in the system is M and the number of transmit antennas is N_tThe number of receiving antennas is N_rSetting the quantization bit width to N_bThen, the overhead of the quantized feedback of the system is: mx 2 XN_b×N_t×N_r(ii) a Wherein, 2 XN_bIs the gain of one sub-carrier, Mx 2 XN_bFor M sub-carrier gains, which is the feedback overhead between a pair of antennas, then based on M × 2 × N_bAnd multiplying by Nt and Nr to obtain the gain on the sub-carrier between all antenna pairs, namely the CSI feedback overhead of the IEEE802.11n system.

(2) Ieee802.11ac system: suppose the number of subcarriers in the system is M and the number of transmit antennas is N_tThe number of receiving antennas is N_rSetting the quantization bit width to N_bThen, the overhead of the quantized feedback of the system is also: mx 2 XN_b×N_t×N_r。

2. Feedback overhead for CSI for IEEE802.11ad systems

Taking an indoor scenario as an example, if the delay quantization bit is 8 (i.e., the delay feedback overhead on one path), the total feedback overhead of the system is: (8 XP +2 XN)_b×P)×N_t×N_r(ii) a Wherein P is the number of the path intermediate diameters, the maximum value is 63, N_bTo quantize bit width, N_tIs the number of transmitted beams, N_rFor receiving the number of beams, 8 × P is the delay feedback overhead of one path, 2 × N_bXP is the gain feedback overhead for one path, (8 XP +2 XN)_b×P)×N_t×N_rI.e. the total cost over all paths. When the system carries out CSI feedback, the feedback information is incomplete and is limited by the number of channel taps.

3. Aiming at an IEEE802.11ay system, the feedback overhead of the method adopting the embodiment of the invention

Suppose the number of transmitting antennas is N_tThe number of receiving antennas is N_rSetting the quantization bit width to N_bP is the number of effective paths in a path, L is lx 8, and L is the byte number of the last effective path in a path, so the feedback overhead in this scheme is:(8+l+2×N_b×P)×N_t×N_r. Wherein 8 is the length of the delay indication field of the CSI encapsulation packet, l is the length of the effective path indication field, and 2 × N_bxPP is the gain overhead of all effective paths on a path, i.e. the length of the effective path gain indication field, and the three are added to be the feedback overhead on a path, and finally (8+ l +2 xN)_b×P)×N_t×N_rThe feedback overhead over all paths in the system is obtained.

Alternatively, the overhead comparison after can be done in one practical case of the 60GHz conference room channel model. Under the model, the number of the effective diameters in each path is 12, and the number of the byte where the last effective diameter is located is 10. Starting from a single-input single-output SISO channel scene, a 2 × 2MIMO channel scene and a 4 × 4MIMO channel scene, the method is adopted to calculate respective CSI feedback overhead.

1. SISO channel scenario: the system comprises a transmitting antenna and a receiving antenna, wherein Nt and Nr are both 1, the number of subcarriers M is 512, the number P of single-channel effective paths is 12, the number of channel taps is 128, and L is 10, and the overhead comparison of the specific three systems can be seen in table 1:

TABLE 1

As can be seen from table 1, the embodiment of the present invention greatly reduces CSI feedback overhead.

2. 2 × 2MIMO channel scenario: including 2 transmitting antenna and 2 receiving antenna, Nt and Nr are 2, and subcarrier number M is 512, and single channel effective path number P is 12, and channel tap number is 128, and L is 10, and the overhead contrast of concrete three kinds of systems can see that table 2 shows:

TABLE 2

As can be seen from table 2, the CSI feedback overhead is greatly reduced in the embodiment of the present invention.

3. 4 × 4MIMO channel scenario: including 4 transmitting antennas and 4 receiving antennas, Nt and Nr are 4, and subcarrier number M is 512, and the number P of single channel effective paths is 12, and the number of channel taps is 128, and L is 10, and the overhead comparison of three specific systems can be seen in table 3:

TABLE 3

As can be seen from table 3, the CSI feedback overhead is greatly reduced in the embodiment of the present invention.

Therefore, it can be seen from the above examples that the method of the embodiment of the present invention can greatly reduce the CSI feedback overhead, and is not limited by the number of channel taps.

Those of ordinary skill in the art will understand that: all or a portion of the steps of implementing the above-described method embodiments may be performed by hardware associated with program instructions. The program may be stored in a computer-readable storage medium. When executed, the program performs steps comprising the method embodiments described above; and the aforementioned storage medium includes: various media that can store program codes, such as ROM, RAM, magnetic or optical disks.

Fig. 14 is a schematic structural diagram of a first embodiment of a feedback apparatus for csi according to an embodiment of the present invention. The feedback device may be a stand-alone communication device or a device integrated in a communication device, and the device may be implemented by software, hardware, or a combination of software and hardware. As shown in fig. 14, the feedback device includes:

an obtaining module 10, configured to obtain time domain channel state information CSI between each antenna pair;

a sending module 11, configured to send a time domain CSI encapsulation packet to a sending end according to the time domain CSI between each antenna pair; the time domain CSI encapsulation packet is used for indicating the field position where each effective path between each antenna pair is located and the effective path gain information of the path corresponding to each antenna pair to the transmitting end; the field position of the effective diameter is used for indicating the sending end to determine the time delay information of the effective diameter according to the field position of the effective diameter and the preset unit time delay; the effective path is a path of which the gain is greater than a preset gain threshold in the path.

Optionally, the obtaining module 10 may be a processor in a receiving end device, and the sending module 11 may be a sender in the receiving end device, or the sending module 11 may also integrate a part of functions of the processor.

The feedback device of channel state information provided in the embodiments of the present invention may implement the above method embodiments, and its implementation principle and technical effect are similar, which are not described herein again.

Optionally, the time-domain CSI encapsulation packet includes a delay indication field, an effective path indication field, and an effective path gain indication field;

the time delay indication field is used for representing a byte number of a last effective path between any antenna pair corresponding to the effective path indication field; each byte in the effective diameter indication field corresponds to 8 diameters, and the effective diameter indication field is used for indicating the field position of each effective diameter between the antenna pairs to the sending end so that the sending end can obtain the time delay information of the effective diameter according to the field position of the effective diameter and the unit time delay; the effective path gain indication field is used for indicating effective path gain quantization information of each antenna pair corresponding path to the transmitting end.

Optionally, the delay indication field is an 8-bit indication field, and the delay indication field is further configured to characterize a length of the effective path indication field.

Fig. 15 is a schematic structural diagram of a second apparatus for feeding back channel state information according to an embodiment of the present invention. On the basis of the foregoing embodiment, further, the foregoing sending module 11 specifically includes:

a first determining unit 111, configured to determine a time-domain MIMO channel matrix according to the time-domain CSI between the antenna pairs, where the time-domain MIMO channel matrix includes a channel impulse response of at least one path, and one path includes at least one path;

a first encoding unit 112, configured to encode, in bytes, a path on each path in the time-domain MIMO channel matrix, and obtain, according to the encoded path, a bit array corresponding to each path, a byte number L of a last effective path on each path corresponding to the bit array, and a number P of the effective paths on each path; wherein each bit of the bit array corresponds to a path on the path;

a second encoding unit 113, configured to perform binary encoding on the L corresponding to each path, and use the encoded L corresponding to each path as a delay indication field of each path;

a deleting unit 114, configured to delete, according to the L corresponding to each path, a bit located after the L in the bit array corresponding to each path to obtain a new bit array, and use the new bit array as an effective path indication field of each path;

a quantization unit 115, configured to obtain the quantized information of the effective path gain of each path according to the number P of the effective paths in each path and the quantized gain information of each effective path in each path, and use the quantized information of the effective path gain as an effective path gain indication field of each path;

a second determining unit 116, configured to determine the time-domain CSI encapsulation packet according to the delay indication field of each path, the effective path indication field of each path, and the effective path gain indication field of each path;

a sending unit 117, configured to send the time domain CSI encapsulation packet to the sending end.

Optionally, the first determining unit 111 is specifically configured to number the transmitting antennas and the receiving antennas respectively, and obtain channel impulse responses between antenna pairs formed by each transmitting antenna and each receiving antenna in sequence according to the numbers of the transmitting antennas and the numbers of the receiving antennas, so as to obtain the time-domain MIMO channel matrix according to the channel impulse responses between the antenna pairs.

Optionally, the first determining unit 111 is specifically configured to receive at least one first beam optimization protocol BRP frame sent by the sending end, and acquire a TRN field in each first BRP frame; and measuring the channel impulse response between each antenna pair according to each TRN domain, and determining the time domain MIMO channel matrix according to the measurement sequence of each TRN domain and the channel impulse response between each antenna pair.

Optionally, the sending unit 117 is further configured to send the permutation sequence of the channel impulse responses in the time-domain MIMO channel matrix to the sending end.

Optionally, the second determining unit 116 is specifically configured to encapsulate the delay indication field, the effective path indication field, and the effective path gain indication field of the same path into a time domain CSI encapsulation packet corresponding to the path; the sending unit 117 is specifically configured to send the time domain CSI encapsulation packet corresponding to each path to the sending end according to the arrangement order of the channel impulse responses in the time domain MIMO channel matrix.

Optionally, the second determining unit 116 is specifically configured to encapsulate the delay indicator field, the effective path indicator field, and the effective path gain indicator field corresponding to each path into a time-domain CSI encapsulation sub-packet, encapsulate each time-domain CSI encapsulation sub-packet into the time-domain CSI encapsulation packet according to the arrangement sequence of each channel impulse response in the time-domain MIMO channel matrix, and further send the time-domain CSI encapsulation packet to the sending end through the sending unit 117.

Optionally, the second determining unit 116 is further configured to perform coding modulation processing on the time-domain CSI encapsulation packet to obtain a modulated CSI encapsulation packet; the sending unit 117 is specifically configured to send the modulated CSI encapsulation packet to the sending end by being carried in a second BRP frame. The second BRP frame carries first indication information and second indication information, the first indication information is used for indicating to the sending end that the second BRP frame carries the modulated CSI encapsulation packet, and the second indication information is used for indicating to the sending end the number of the effective paths on each path.

As shown in fig. 15, optionally, the feedback device may further include a receiving module 12 and a determining module 13;

a receiving module 12, configured to receive third indication information sent by the sending end, where the third indication information is used to indicate the number of sending antennas to the receiving end;

and a judging module 13, configured to judge whether to perform time domain CSI feedback according to the number of the transmitting antennas and the number of the receiving antennas.

Fig. 16 is a schematic structural diagram of an embodiment of a communication device according to an embodiment of the present invention. As shown in fig. 16, the communication device may include a transmitter 20, a processor 21, a memory 22, and at least one communication bus 23. The communication bus 23 is used to realize communication connection between the elements. The memory 22 may include a high speed RAM memory 22, and may also include a non-volatile storage NVM, such as at least one disk memory 22, where the memory 22 may store various programs for performing various processing functions and implementing the method steps of the present embodiment. Optionally, the communication device may further include a receiver 24, the receiver 24 in this embodiment may be a corresponding input interface having a communication function and a function of receiving information, and may also be a radio frequency module or a baseband module on the communication device, and the transmitter 20 in this embodiment may be a corresponding output interface having a communication function and a function of transmitting information, and may also be a radio frequency module or a baseband module on the communication device. Alternatively, the transmitter 20 and the receiver 24 may be integrated into one communication interface, or may be two independent communication interfaces.

In this embodiment, the processor 21 is configured to obtain time domain channel state information CSI between each antenna pair;

a transmitter 20, configured to send a time domain CSI encapsulation packet to a sending end according to the time domain CSI between each antenna pair; the time domain CSI encapsulation packet is used for indicating the field position where each effective path between each antenna pair is located and the effective path gain information of the path corresponding to each antenna pair to the transmitting end; the field position of the effective diameter is used for indicating the sending end to determine the time delay information of the effective diameter according to the field position of the effective diameter and the preset unit time delay; the effective path is a path of which the gain is greater than a preset gain threshold in the path.

Optionally, the processor 21 is further configured to determine a time-domain multiple-input multiple-output MIMO channel matrix according to the time-domain CSI between each antenna pair, encode a path on each path in the time-domain MIMO channel matrix according to bytes, and obtain, according to the encoded path, a bit array corresponding to each path, a byte number L of a last effective path on each path corresponding to the bit array, and a number P of effective paths on each path; binary coding is carried out on the L corresponding to each path, the coded L corresponding to each path is used as a time delay indication field of each path, bit positions behind the L in the bit number group corresponding to each path are deleted according to the L corresponding to each path, a new bit array is obtained, and the new bit array is used as an effective path indication field of each path; obtaining the gain quantization information of the effective diameter of each path according to the number P of the effective diameters on each path and the gain information after the quantization of each effective diameter on each path, and using the gain quantization information of the effective diameter as an effective diameter gain indication field of each path; determining the time domain CSI encapsulated packet according to the delay indication field of each path, the effective path indication field of each path, and the effective path gain indication field of each path, and sending the time domain CSI encapsulated packet to the sending end through the sender 20;

Optionally, the processor 21 determines a time domain MIMO channel matrix according to the time domain CSI between each antenna pair, and specifically includes:

the processor 21 is specifically configured to number the transmitting antennas and the receiving antennas respectively, obtain channel impulse responses between antenna pairs formed by each transmitting antenna and each receiving antenna in sequence according to the numbers of the transmitting antennas and the numbers of the receiving antennas, and obtain the time-domain MIMO channel matrix according to the channel impulse responses between the antenna pairs.

Optionally, the receiver 24 is configured to receive at least one first beam optimization protocol BRP frame sent by the sending end; the processor 21 is specifically configured to acquire a TRN field in each first BRP frame, measure a channel impulse response between each antenna pair according to each TRN field, and determine the time-domain MIMO channel matrix according to a measurement order of each TRN field and the channel impulse response between each antenna pair.

Optionally, the transmitter 20 is further configured to, after the processor 21 determines a time-domain MIMO channel matrix according to the time-domain CSI between each antenna pair, send an arrangement sequence of each channel impulse response in the time-domain MIMO channel matrix to the sending end.

Optionally, the processor 21 is specifically configured to encapsulate a delay indication field, an effective path indication field, and an effective path gain indication field of the same path into a time domain CSI encapsulation packet corresponding to the path; the transmitter 20 is specifically configured to send the time domain CSI encapsulation packet corresponding to each path to the sending end according to the arrangement order of the channel impulse responses in the time domain MIMO channel matrix.

Optionally, the processor 21 is specifically configured to encapsulate the delay indicator field, the effective path indicator field, and the effective path gain indicator field corresponding to each path into a time-domain CSI encapsulation sub-packet, encapsulate each time-domain CSI encapsulation sub-packet into the time-domain CSI encapsulation packet according to an arrangement sequence of channel impulse responses in the time-domain MIMO channel matrix, and further send the time-domain CSI encapsulation packet to the sending end through the sender 20.

Optionally, the processor 21 is further configured to perform coding modulation processing on the time domain CSI encapsulation packet to obtain a modulated CSI encapsulation packet; the transmitter 20 is specifically configured to send the modulated CSI encapsulation packet to the sending end by being carried in a second BRP frame; the second BRP frame carries first indication information and second indication information, the first indication information is used for indicating to the sending end that the second BRP frame carries the modulated CSI encapsulation packet, and the second indication information is used for indicating to the sending end the number of the effective paths on each path.

Optionally, the receiver 24 is further configured to receive third indication information sent by the sending end before the sender 20 sends a time domain CSI encapsulated packet to the sending end according to the time domain CSI between each antenna pair, where the third indication information is used to indicate the number of sending antennas to the receiving end; the processor 21 is further configured to determine whether to perform time domain CSI feedback according to the number of the transmitting antennas and the number of the receiving antennas.

The communication device provided by the embodiment of the present invention may implement the above method embodiment, and the implementation principle and technical effect are similar, which are not described herein again.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A feedback method for channel state information, comprising:

The receiving end obtains the time-domain channel state information CSI between each antenna pair;

The receiving end sends a time-domain CSI encapsulation packet to the transmitting end according to the time-domain CSI between the antenna pairs; wherein, the time-domain CSI encapsulation packet is used to indicate to the transmitting end that each pair of antennas has a time-domain CSI encapsulation packet. The field position where each effective path is located, and the effective path gain information of the path corresponding to each antenna pair; the field position where the effective path is located is used to indicate the transmitting end according to the field position where the effective path is located and the preset The unit delay determines the delay information of the effective path; the effective path is a path whose gain is greater than a preset gain threshold in the path.

2. The method according to claim 1, wherein the time-domain CSI encapsulation packet comprises a delay indication field, an effective path indication field and an effective path gain indication field;

The delay indication field is used to represent the byte number corresponding to the effective path indication field of the last effective path between any antenna pair;

Each byte in the effective path indication field corresponds to 8 paths, and the effective path indication field is used to indicate to the transmitting end the field position where each effective path between the pair of antennas is located, so that all The transmitting end obtains the delay information of the effective path according to the field position where the effective path is located and the unit delay;

The effective path gain indication field is used to indicate to the transmitting end the effective path gain quantization information of the path corresponding to each antenna pair.

3. The method according to claim 2, wherein the delay indication field is an 8-bit indication field.

4. The method according to claim 3, wherein the delay indication field is further used to represent the length of the effective path indication field.

5. The method according to claim 4, wherein the receiving end sends a time-domain CSI encapsulation packet to the transmitting end according to the time-domain CSI between the antenna pairs, specifically comprising:

The receiving end determines a time-domain multiple-input multiple-output MIMO channel matrix according to the time-domain CSI between the antenna pairs, wherein the time-domain MIMO channel matrix includes a channel impulse response of at least one path, and one path includes at least one trail;

The receiving end encodes the path on each path in the time-domain MIMO channel matrix by byte, and obtains the bit array corresponding to each path and the path on each path according to the encoded path. The last valid path corresponds to the byte number L on the bit array and the number P of valid paths on each of the paths; wherein, each bit of the bit array corresponds to a path on the path;

The receiving end performs binary encoding on the L corresponding to each of the paths, and uses the encoded L corresponding to each of the paths as a delay indication field of each of the paths;

According to the L corresponding to each of the paths, the receiving end deletes the bits located after the L in the bit array corresponding to each of the paths to obtain a new bit array, and uses the new bit array as each bit array. a valid path indication field for the path;

The receiving end obtains the effective path gain quantization information of each of the paths according to the number P of effective paths on each of the paths and the quantized gain information of each effective path on each of the paths, and uses The effective path gain quantization information is used as the effective path gain indication field of each of the paths;

The receiving end determines the time-domain CSI encapsulation packet according to the delay indication field of each of the paths, the effective path indication field of each of the paths, and the effective path gain indication field of each of the paths. The transmitting end sends the time-domain CSI encapsulation packet.

6. The method according to claim 5, wherein the receiving end determines a time-domain MIMO channel matrix according to the time-domain CSI between the antenna pairs, specifically comprising:

The receiving end numbers the transmitting antenna and the receiving antenna respectively;

The receiving end obtains the channel impulse response between the antenna pair formed by each transmitting antenna and each receiving antenna in sequence according to the number of the transmitting antenna and the number of the receiving antenna;

The receiving end obtains the time-domain MIMO channel matrix according to the channel impulse response between each antenna pair.

7. The method according to claim 5, wherein the receiving end determines a time-domain MIMO channel matrix according to the time-domain CSI between the antenna pairs, specifically comprising:

The receiving end receives at least one first beam optimization protocol BRP frame sent by the transmitting end;

The receiving end obtains the training TRN domain in each of the first BRP frames;

The receiving end measures the channel impulse response between each antenna pair according to each TRN domain, and determines the time domain MIMO according to the measurement order of each TRN domain and the channel impulse response between each antenna pair channel matrix.

8. The method according to any one of claims 5-7, wherein after the receiving end determines the time-domain MIMO channel matrix according to the time-domain CSI between the respective antenna pairs, the method further comprises:

The receiving end sends the order of the impulse responses of each channel in the time-domain MIMO channel matrix to the transmitting end.

9 . The method according to claim 8 , wherein, according to the delay indication field of each path, the effective path indication field of each path, and the effective path gain indication of each path field, determine the time-domain CSI encapsulation packet, and send the time-domain CSI encapsulation packet to the sender, specifically including:

The receiving end encapsulates the delay indication field, effective path indication field, and effective path gain indication field of the same path into a time-domain CSI encapsulation packet corresponding to the path;

The receiving end sends the time-domain CSI encapsulation packets corresponding to each path to the transmitting end respectively according to the order of the impulse responses of the channels in the time-domain MIMO channel matrix.

10 . The method according to claim 8 , wherein, according to the delay indication field of each path, the effective path indication field of each path, and the effective path gain indication of each path field, determine the time-domain CSI encapsulation packet, and send the time-domain CSI encapsulation packet to the sender, specifically including:

The receiving end encapsulates the delay indication field, the effective path indication field, and the effective path gain indication field corresponding to each path into a time-domain CSI encapsulation sub-packet;

The receiving end encapsulates each time-domain CSI encapsulation sub-packet into the time-domain CSI encapsulation packet according to the arrangement order of the impulse responses of each channel in the time-domain MIMO channel matrix, and sends it to the transmitting end.

11. The method according to claim 5, wherein the sending the time-domain CSI encapsulation packet to the transmitting end specifically comprises:

The receiving end performs coding and modulation processing on the time-domain CSI encapsulation packet to obtain a modulated CSI encapsulation packet;

The receiving end carries the modulated CSI encapsulation packet in a second BRP frame and sends it to the transmitting end.

12. The method according to claim 11, wherein the second BRP frame carries first indication information and second indication information, and the first indication information is used to indicate to the transmitting end the first indication information. The modulated CSI encapsulation packet is carried in the second BRP frame, and the second indication information is used to indicate to the transmitting end the number of valid paths on each path.

13. The method according to any one of claims 1-7 or 9-12, wherein the receiving end sends time-domain CSI to the transmitting end according to the time-domain CSI between the antenna pairs Before packaging the package, the method further includes:

The receiving end receives third indication information sent by the transmitting end, where the third indication information is used to indicate the number of transmitting antennas to the receiving end;

The receiving end determines whether to perform time-domain CSI feedback according to the number of the transmitting antennas and the number of the receiving antennas.

14. A communication device, comprising:

a processor, configured to acquire time-domain channel state information CSI between each antenna pair;

a transmitter, configured to send a time-domain CSI encapsulation packet to the transmitting end according to the time-domain CSI between the antenna pairs; wherein the time-domain CSI encapsulation packet is used to indicate to the transmitting end the difference between the antenna pairs The field position where each effective path is located, and the effective path gain information of the path corresponding to each antenna pair; the field position where the effective path is located is used to indicate that the transmitting end is based on the field position where the effective path is located and preset The unit delay of , determines the delay information of the effective path; the effective path is a path whose gain is greater than a preset gain threshold in the path.

15. The communication device according to claim 14, wherein the time-domain CSI encapsulation packet comprises a delay indication field, an effective path indication field and an effective path gain indication field;

16. The communication device according to claim 15, wherein the delay indication field is an 8-bit indication field.

17. The communication device according to claim 16, wherein the delay indication field is further used to represent the length of the effective path indication field.

18 . The communication device according to claim 17 , wherein the processor is further configured to determine a time-domain multiple-input multiple-output MIMO channel matrix according to the time-domain CSI between the antenna pairs, and to determine the time-domain multiple-input multiple-output MIMO channel matrix. The path on each path in the time-domain MIMO channel matrix is encoded by bytes, and the bit array corresponding to each path and the corresponding bit array corresponding to each path and the last valid path on each path are obtained according to the encoded path. The byte number L on the bit array, the number P of valid paths on each of the paths; and, binary coding is performed on the L corresponding to each of the paths, and the coded corresponding to each of the paths is encoded. L is used as the delay indication field of each of the paths, and, according to the L corresponding to each of the paths, the bits located after the L in the bit array corresponding to each of the paths are deleted to obtain a new bit array , and use the new bit array as the effective path indication field of each of the paths; and, according to the number P of effective paths on each of the paths and the quantized obtain the effective path gain quantization information of each of the paths, and use the effective path gain quantization information as the effective path gain indication field of each of the paths; and, according to the time delay of each of the paths an indication field, an effective path indication field of each of the paths, and an effective path gain indication field of each of the paths, determine the time-domain CSI encapsulation packet, and send the time-domain CSI encapsulation packet to the transmitting end through the transmitter Domain CSI encapsulation package;

The time-domain MIMO channel matrix includes a channel impulse response of at least one path, and one path includes at least one path; each bit of the bit array corresponds to one path on the path.

19. The communication device according to claim 18, wherein the processor determines a time-domain MIMO channel matrix according to the time-domain CSI between the antenna pairs, specifically comprising:

The processor is specifically configured to number the transmitting antenna and the receiving antenna respectively, and obtain the antenna pair formed by each transmitting antenna and each receiving antenna in sequence according to the number of the transmitting antenna and the number of the receiving antenna and obtain the time-domain MIMO channel matrix according to the channel impulse response between each antenna pair.

20. The communication device of claim 18, wherein the communication device further comprises a receiver;

the receiver, configured to receive at least one first beam optimization protocol BRP frame sent by the transmitter;

The processor is specifically configured to acquire the training TRN domain in each of the first BRP frames, measure the channel impulse response between each antenna pair according to each TRN domain, and measure the channel impulse response between each antenna pair according to each TRN domain The order and channel impulse response between each antenna pair determine the time domain MIMO channel matrix.

21. The communication device according to any one of claims 18-20, wherein the transmitter is further configured to, in the processor, determine the time domain according to the time domain CSI between the antenna pairs After the MIMO channel matrix is obtained, the arrangement order of the impulse responses of each channel in the time-domain MIMO channel matrix is sent to the transmitting end.

22 . The communication device according to claim 21 , wherein the processor is specifically configured to encapsulate a delay indication field, an effective path indication field, and an effective path gain indication field of the same path into a corresponding field of the path. 23 . The time-domain CSI encapsulation package;

The transmitter is specifically configured to send the time-domain CSI encapsulation packet corresponding to each path to the transmitter according to the order of the impulse responses of each channel in the time-domain MIMO channel matrix.

23. The communication device according to claim 21, wherein the processor is specifically configured to encapsulate the delay indication field, effective path indication field, and effective path gain indication field corresponding to each path into a time domain CSI encapsulation sub-packets, and encapsulates each time-domain CSI encapsulation sub-packet into the time-domain CSI encapsulation packet according to the arrangement order of the impulse responses of each channel in the time-domain MIMO channel matrix, and then sends to the time-domain CSI encapsulation packet through the transmitter. the sender.

24. The communication device according to claim 18, wherein the processor is further configured to perform coding and modulation processing on the time-domain CSI encapsulation packet to obtain a modulated CSI encapsulation packet;

The transmitter is specifically configured to carry the modulated CSI encapsulation packet in the second BRP frame and send it to the transmitter.

25. The communication device according to claim 24, wherein the second BRP frame carries first indication information and second indication information, and the first indication information is used to indicate to the transmitting end the The second BRP frame carries the modulated CSI encapsulation packet, and the second indication information is used to indicate the number of valid paths on each path to the transmitting end.

26. The communication device according to any one of claims 14-20 or 22-25, wherein the receiver is further configured to, at the transmitter, transmit to the transmitter according to the time domain CSI between the antenna pairs. Before the transmitting end sends the time-domain CSI encapsulation packet, receiving third indication information sent by the transmitting end, where the third indication information is used to indicate the number of transmitting antennas to the receiving end;