CN102469473B - A kind of channel measuring method based on Downlink Control Information and system - Google Patents

Abstract

The present invention discloses a channel measurement method and system based on downlink control information. When the network side configures the downlink transmission mode 9 for the receiving node, the network side notifies the receiving node of the downlink control information format adopted for sending the downlink control information The channel measurement method to be used; when the receiving node knows that the downlink transmission of the network side adopts the transmission mode 9, the receiving node determines the channel measurement method to be adopted according to the downlink control information format used by the network side to send the downlink control information. The present invention proposes a corresponding solution for which downlink control information format should be adopted for the new transmission mode 9 in LTE R10 and how the receiving node should determine the channel measurement mode.

Description

A channel measurement method and system based on downlink control information

technical field

The present invention relates to the technical field of communications, and more specifically, to a channel measurement method and system based on downlink control information.

Background technique

In LTE (Long Term Evolution, Long Term Evolution System) Release8/9, in order to measure the quality of the channel and demodulate the received data symbols, a CRS (Common Reference Signal, common reference signal) is designed, and the receiving node such as ( User Equipment, user equipment) can measure the channel through the CRS, so as to determine the receiving node to perform cell reselection and handover to the target cell, and measure the channel quality in the connection state of the receiving node. When the interference level is high, the physical layer can disconnect the connection through high-layer-related radio link connection failure signaling.

In LTE-Advanced (Long Term Evolution-Advanced, Long Term Evolution Advanced System) R10, in order to further improve the average spectrum utilization rate of the cell, the spectrum utilization rate of the cell edge and the throughput rate of each receiving node, two reference signals are defined respectively: CSI-RS (Channel Information Reference Signal) and DMRS (Demodulation Reference Signal). Among them, CSI-RS is used for channel measurement. Through the measurement of CSI-RS, the PMI (Precoding Matrix Indicator, precoding matrix index) and CQI (Channel Quality Indicator) that the receiving node needs to feed back to the network side (such as the base station eNodeB) can be calculated. , channel quality information indication) and RI (Rank Indicator, rank indication).

The distribution of CSI-RS in the time domain and frequency domain is sparse, and it is necessary to ensure that only one CSI-RS pilot density per antenna port of the serving cell is included in one RB (Resource Block, resource block), and the time domain The field is used as the period of the CSI-RS in multiples of 5 ms. Sparse CSI-RS can support the configuration of 8 antennas on the network side, and advantageously supports the measurement configuration of adjacent cells. The network side can use any of the sending modes 1~7 for the receiving node of R8, any of the sending modes 1~8 for the R9 receiving node, and can use sending mode 1~8 for the R10 receiving node. 9 any sending mode. And in R8 and R9, corresponding to each transmission mode, there are two DCI Formats (Downlink Control Information Format, downlink control information format), among which for each transmission mode, there is a DCI Format with Fall back mode DCI Format 1A (fallback mode DCI Format). This DCI Format design considers the fallback problem of each transmission mode. Since the transmission mode configuration of the receiving node on the network side is semi-statically configured through high-level signaling, when the speed of the receiving node suddenly increase, or the channel quality suddenly deteriorates, or receives some high-level signaling, etc., the network side can use the transmission diversity method to send data to the receiving node in the configured transmission mode, where the transmission diversity method corresponds to this A DCI Format 1A. In this way, the retransmission probability and call loss rate are guaranteed to be as small as possible to a certain extent, so there is a guarantee of transmission diversity for each transmission mode.

The following technical problems exist in the current technology: At present, for the new transmission mode 9 in LTE R10, which downlink control information format should be used, and how the receiving node should determine the channel measurement method, no corresponding specific solution has been proposed.

Contents of the invention

The technical problem solved by the present invention is to provide a channel measurement method and system based on downlink control information, and the network side notifies the receiving node to adopt the corresponding channel measurement method through the format of the downlink control information.

In order to solve the above technical problems, the present invention provides a channel measurement method based on downlink control information, the method comprising:

When the network side configures the receiving node to use the sending mode 9 for downlink transmission, the network side notifies the receiving node of the channel measurement method to be adopted through the downlink control information format used for sending the downlink control information.

Further, the downlink control information format adopted by the network side to send the downlink control information includes at least: DCI-Format 1A and DCI-Format 2C.

Further, when the downlink control information format adopted by the network side is DCI-Format 1A, the receiving node is notified to use a common reference signal (CRS) for channel measurement.

Further, when the downlink control information format adopted by the network side is DCI-Format 2C, the receiving node is notified to use a channel information reference signal (CSI-RS) to perform channel measurement.

The present invention also provides another channel measurement method based on downlink control information, the method comprising:

When the receiving node knows that the downlink transmission of the network side adopts the transmission mode 9, the receiving node determines the channel measurement method to be adopted according to the downlink control information format adopted by the network side for sending downlink control information.

Further, the receiving node learns that the network side downlink transmission adopts transmission mode 9 through high-level signaling.

Further, the receiving node detects the downlink control information format used by the network side to send the downlink control information by performing blind detection on the physical downlink control channel (PDCCH).

Further, when the downlink control information format adopted by the network side is DCI-Format 1A, the receiving node determines to use CRS for channel measurement; when the downlink control information format adopted by the network side is DCI-Format 2C, The receiving node determines to use the CSI-RS to perform channel measurement.

The present invention also provides a channel measurement system based on downlink control information, which is applied to the network side, and the system includes:

a downlink sending unit, configured to send downlink control information to the receiving node;

The channel measurement mode notification unit is used to notify the receiving node of the channel measurement mode to be adopted by using the downlink control information format used by the downlink sending unit to send the downlink control information when the network side configures the downlink transmission for the receiving node to adopt the transmission mode 9 .

Further, the downlink control information format adopted by the downlink sending unit to send the downlink control information includes at least: DCI-Format 1A and DCI-Format 2C.

Further, the channel measurement mode notification unit is used for:

When the downlink control information format adopted by the downlink sending unit is DCI-Format 1A, notify the receiving node to use CRS for channel measurement;

When the downlink control information format adopted by the downlink sending unit is DCI-Format 2C, notify the receiving node to use CSI-RS to perform channel measurement.

The present invention also provides another channel measurement system based on downlink control information, which is applied to a receiving node, and the system includes:

A transmission mode acquisition unit, configured to acquire the transmission mode adopted by the network side for downlink transmission;

a downlink receiving unit, configured to receive the downlink control information sent by the network side, and detect the downlink control information format used by the network side to send the downlink control information;

The channel measurement mode determination unit is used to determine the downlink control information format to be used according to the detected downlink control information format used by the network side to send downlink control information when the transmission module learning unit knows that the downlink transmission of the network side adopts transmission mode 9. channel measurement method.

Further, the transmission mode obtaining unit is configured to obtain the transmission mode adopted by the network side for downlink transmission through high-layer signaling.

Further, the downlink receiving unit is configured to detect the downlink control information format used by the network side to send the downlink control information by performing blind detection on the PDCCH.

Further, the channel measurement method determination unit is used to determine that the channel measurement is performed using CRS when the downlink receiving unit detects that the downlink control information format adopted by the network side is DCI-Format 1A; When the unit detects that the downlink control information format adopted by the network side is DCI-Format 2C, it determines to use CSI-RS for channel measurement.

The present invention proposes a corresponding solution for the newly added transmission mode 9 in LTE R10, which downlink control information format should be used, and how the receiving node should determine the channel measurement method. The network side notifies the receiving node to use the downlink control information format. The corresponding channel measurement method, or the receiving node determines the channel measurement method according to the format of the downlink control information.

Description of drawings

The accompanying drawings described here are used to provide a further understanding of the present invention and constitute a part of the application. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations to the present invention. In the attached picture:

FIG. 1 is a process of channel measurement performed by a receiving node based on downlink control information according to an embodiment of the present invention.

Detailed ways

The present invention proposes a channel measurement method based on downlink control information, specifically adopting the following technical solutions:

When the network side configures the receiving node to use the sending mode 9 for downlink transmission, the network side notifies the receiving node of the channel measurement method to be adopted through the downlink control information format used for sending the downlink control information.

Further, the downlink control information format adopted by the network side to send the downlink control information includes at least: DCI-Format 1A and DCI-Format 2C.

Further, when the network side adopts DCI-Format 1A, notify the receiving node to use CRS to perform channel measurement.

Further, when the network side adopts DCI-Format 2C, notify the receiving node to use CSI-RS to perform channel measurement.

In addition, the present invention also provides a channel measurement method based on downlink control information, specifically adopting the following technical solutions:

When the receiving node knows that the downlink transmission of the network side adopts the transmission mode 9, the receiving node determines the channel measurement mode to be adopted according to the downlink control information format used for the downlink control information transmission of the network side.

Further, the receiving node learns that the network side downlink transmission adopts transmission mode 9 through high-level signaling.

Further, the receiving node detects the downlink control information format used by the network side to send the downlink control information by performing blind detection on the PDCCH.

Further, the receiving node transmits the downlink control information format adopted by the network side, and when the network side adopts DCI-Format 1A, the receiving node uses CRS to perform channel measurement; when the network side When the DCI-Format 2C is used on the side, the receiving node uses CSI-RS to perform channel measurement.

In order to facilitate the description of the present invention, the implementation of the technical solutions of the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that, in the case of no conflict, the embodiments in the present application and the features in the embodiments can be combined arbitrarily with each other.

Embodiment one

Fig. 1 shows the flow of measurement configuration reception and channel measurement based on downlink control information according to an embodiment of the present invention. As shown in Fig. 1, the flow mainly includes the following steps:

Step 1, the base station sends downlink data or downlink control information to the receiving node, maps the sent data to PDSCH (Physical Downlink Sharing Channel, physical downlink shared channel), and sends the sent control information to PDCCH (Physical Downlink Control Channel, physical downlink control channel);

Step 2, the base station combines PDSCH and PDCCH;

Step 3, the base station inserts the generated pilot into the downlink subframe;

Step 4, the downlink subframe passes through the channel;

Step 5, the receiving node receives the downlink subframe;

Step 6, the receiving node detects the format of the downlink control information;

Step 7: The receiving node judges whether the format of the downlink control information is DCI-Format 1A or DCI-Format 2C. If it is DCI-Format 1A, use CRS for channel measurement; if it is DCI-Format 2C, use CSI-RS for channel measurement. Measurement.

In the above process, when the transmission mode is configured as transmission mode 9, the network side can configure the downlink control information to adopt DCI-Format 2C, and notify the receiving node implicitly that it needs to perform channel measurement through CSI-RS. When the receiving node is in RRC-Connected (radio resource control-connected state) mode, the network side will semi-statically configure the sending mode of the receiving node, and notify the receiving node through high-level signaling; when the receiving node knows that the network side uses sending mode 9 to its When sending data, the downlink control information is detected by blind detection of PDCCH, and the downlink control information format is obtained. If the blind detection result of the receiving node is DCI-Format 2C, then the receiving node uses CSI-RS in the next channel measurement to proceed.

In the above process, when the transmission mode is configured as transmission mode 9, the network side can also configure the downlink control information to adopt DCI-Format 1A, and at this time, the network side notifies the receiving node implicitly to perform channel measurement through CRS. When the receiving node works in RRC-Connected mode, the network side will semi-statically configure the sending mode of the receiving node. When the result of blind detection is DCI-Format 1A, then the receiving node uses CRS for the next channel measurement.

After the receiving node completes the channel measurement, it can use the measurement results to calculate CQI (Channel Quality Indicator, channel quality indicator), PMI, and RI, and correct the corresponding CQI value according to different measurement methods, so that it is consistent with the PDSCH CQI values match.

Embodiment two

When an R10 receiving node is connected to an R10 network side, after a certain period of statistics on the network side, it is found that the optimal transmission mode of this R10 is transmission mode 9, and the network side will configure the transmission mode in the high-level signaling Mode 9, and send it to the receiving node on the PDSCH through RRC (Radio Resource Control, radio resource control) signaling.

The receiving node obtains the transmission mode configured by the network side by demodulating the PDSCH related to RRC signaling. When it knows that the transmission mode configured for it by the network side is transmission mode 9, the receiving node only needs to consider the Blind detection of downlink control information DCI Format 1A and DCI Format 2C.

For a R10 receiving node, if the transmission mode 9 is used for transmission, the network side can notify the receiving node which transmission mode 9 is used for downlink transmission by mapping the DCI Format1A downlink control information to the corresponding time-frequency resource in the PDCCH sending method. When the network side maps data and pilots to PDSCH REs (Resource Elements, resource elements), and maps control information and pilots to PDCCH REs, then sends them to the target receiving node through radio frequency.

When the receiving node receives the downlink subframe sent by the network side, it first undergoes radio frequency processing and other operations to modulate the high-frequency signal to the baseband, and then the receiving node first blindly detects the PDCCH. When the receiving node blindly detects the control information in the PDCCH, it uses When it is DCI Format 1A, the receiving node performs demodulation in the way of transmit diversity, and uses CRS to perform channel measurement.

Embodiment three

The network side configures a R10 receiving node to use transmission mode 9 for transmission in high-level signaling. At this time, the network side uses DCI Format2C and places it in the PDCCH to notify the receiving node which multi-antenna transmission method in transmission mode 9 is used for downlink transmission. The network side maps data and pilots to PDSCH REs, and maps control information and pilots to PDCCH REs, and then sends them to the target receiving node through radio frequency.

When the receiving node receives the downlink subframe sent by the network side, it first undergoes radio frequency processing and other operations to modulate the high-frequency signal to the baseband, and then the receiving node first blindly detects the PDCCH. When the receiving node blindly detects the control information in the PDCCH, it uses When it is DCI Format 2C, the receiving node performs demodulation according to the R10 transmission mode, and the channel measurement uses CSI-RS for channel measurement. Then the receiving node calculates the CQI according to the ratio of PDSCH EPRE (RE average power) and CSI-RS EPRE and feeds it back to the network side for MCS (modulation and coding scheme) adjustment.

In addition, an embodiment of the present invention also provides a channel measurement system based on downlink control information, which is applied to the network side, and the system mainly includes:

a downlink sending unit, configured to send downlink control information to the receiving node;

The channel measurement mode notification unit is used to notify the receiving node of the channel measurement mode to be adopted by using the downlink control information format used by the downlink sending unit to send the downlink control information when the network side configures the downlink transmission for the receiving node to adopt the transmission mode 9 .

Further, the downlink control information format adopted by the downlink sending unit to send the downlink control information includes at least: DCI-Format 1A and DCI-Format 2C.

Further, the channel measurement mode notification unit is used for:

When the downlink control information format adopted by the downlink sending unit is DCI-Format 1A, notify the receiving node to use CRS for channel measurement;

When the downlink control information format adopted by the downlink sending unit is DCI-Format 2C, notify the receiving node to use CSI-RS to perform channel measurement.

In addition, the present invention also provides another channel measurement system based on downlink control information, which is applied to the receiving node, and the system includes:

A transmission mode acquisition unit, configured to acquire the transmission mode adopted by the network side for downlink transmission;

a downlink receiving unit, configured to receive the downlink control information sent by the network side, and detect the downlink control information format used by the network side to send the downlink control information;

The channel measurement mode determination unit is used to determine the downlink control information format to be used according to the detected downlink control information format used by the network side to send downlink control information when the transmission module learning unit knows that the downlink transmission of the network side adopts transmission mode 9. channel measurement method.

Further, the transmission mode obtaining unit is configured to obtain the transmission mode adopted by the network side for downlink transmission through high-layer signaling.

Further, the downlink receiving unit is configured to detect the downlink control information format used by the network side to send the downlink control information by performing blind detection on the PDCCH.

Further, the channel measurement method determination unit is used to determine that the channel measurement is performed using CRS when the downlink receiving unit detects that the downlink control information format adopted by the network side is DCI-Format 1A; When the unit detects that the downlink control information format adopted by the network side is DCI-Format 2C, it determines to use CSI-RS for channel measurement.

The above are only preferred implementation examples of the present invention, and are not intended to limit the present invention. The present invention can also have other various embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art can Various corresponding changes and modifications are made in the present invention, but these corresponding changes and modifications should all belong to the protection scope of the appended claims of the present invention.

Obviously, those skilled in the art should understand that each module or each step of the above-mentioned present invention can be realized by a general-purpose computing device, and they can be concentrated on a single computing device, or distributed in a network formed by multiple computing devices Alternatively, they may be implemented in program code executable by a computing device so that they may be stored in a storage device to be executed by a computing device, and in some cases in an order different from that shown here The steps shown or described are carried out, or they are separately fabricated into individual integrated circuit modules, or multiple modules or steps among them are fabricated into a single integrated circuit module for implementation. As such, the present invention is not limited to any specific combination of hardware and software.

Claims (8)

1. A channel measurement method based on downlink control information, characterized in that the method comprises: When the network side configures the receiving node to use the transmission mode 9 for downlink transmission, the network side notifies the receiving node of the channel measurement method to be adopted by sending the downlink control information format used for the downlink control information; The downlink control information format used by the network side to send the downlink control information includes at least: DCI-Format 1A and DCI-Format 2C; When the downlink control information format adopted by the network side is DCI-Format 1A, notify the receiving node to use a common reference signal (CRS) for channel measurement; When the downlink control information format adopted by the network side is DCI-Format 2C, notify the receiving node to use a channel information reference signal (CSI-RS) to perform channel measurement. 2. A channel measurement method based on downlink control information, characterized in that the method comprises: When the receiving node knows that the downlink transmission of the network side adopts the transmission mode 9, the receiving node determines the channel measurement method to be adopted according to the downlink control information format used by the network side to send the downlink control information; When the downlink control information format adopted by the network side is DCI-Format 1A, the receiving node determines to use CRS for channel measurement; when the downlink control information format adopted by the network side is DCI-Format 2C, the receiving node The node determines to use the CSI-RS for channel measurement. 3. The method of claim 2, wherein The receiving node learns that the downlink transmission on the network side adopts transmission mode 9 through high-level signaling. 4. The method of claim 2, wherein, The receiving node detects the downlink control information format used by the network side to send the downlink control information by performing blind detection on the physical downlink control channel (PDCCH). 5. A channel measurement system based on downlink control information, characterized in that it is applied to the network side, and the system includes: a downlink sending unit, configured to send downlink control information to the receiving node; The channel measurement mode notification unit is used to notify the receiving node of the channel measurement mode to be adopted by using the downlink control information format used by the downlink sending unit to send the downlink control information when the network side configures the downlink transmission for the receiving node to adopt the transmission mode 9 ; The downlink control information format adopted by the downlink sending unit to send downlink control information includes at least: DCI-Format 1A and DCI-Format 2C; The channel measurement mode notification unit is used for: When the downlink control information format adopted by the downlink sending unit is DCI-Format 1A, notify the receiving node to use CRS for channel measurement; When the downlink control information format adopted by the downlink sending unit is DCI-Format 2C, notify the receiving node to use CSI-RS to perform channel measurement. 6. A channel measurement system based on downlink control information, characterized in that it is applied to a receiving node, and the system includes: A transmission mode acquisition unit, configured to acquire the transmission mode adopted by the network side for downlink transmission; a downlink receiving unit, configured to receive the downlink control information sent by the network side, and detect the downlink control information format used by the network side to send the downlink control information; The channel measurement mode determination unit is used to determine the downlink control information format to be used according to the detected downlink control information format used by the network side to send downlink control information when the transmission module learning unit knows that the downlink transmission of the network side adopts transmission mode 9. channel measurement method; The channel measurement method determination unit is used to determine that the channel measurement is performed using CRS when the downlink receiving unit detects that the downlink control information format adopted by the network side is DCI-Format 1A; when the downlink receiving unit detects that When the downlink control information format adopted by the network side is DCI-Format 2C, it is determined to use CSI-RS for channel measurement. 7. The system of claim 6, wherein: The transmission mode obtaining unit is configured to obtain the transmission mode adopted by the network side for downlink transmission through high-layer signaling. 8. The system of claim 6, wherein: The downlink receiving unit is configured to detect the downlink control information format used by the network side to send the downlink control information by performing blind detection on the PDCCH.