CN101686214B - Method and device for performing channel quality indicator estimation - Google Patents
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Abstract
The invention discloses a method for performing channel quality indicator (CQI) estimation, which is applied to a multi-input multi-output system. The method comprises the following steps: according to a received sounding reference signal transmitted by a user terminal, performing uplink channel estimation; according to an uplink channel estimation result, scheduling the user terminal, and allocating physical resources to be occupied in next transmission to the user terminal; and according to the uplink channel information of each physical resource, performing the CQI estimation to obtain a CQI. At the same time, the invention also discloses a device for performing the CQI estimation in the multi-input multi-output system. The method and the device can estimate the CQI of any sub-band because the sounding reference signal transmitted by the user terminal can cover the whole bandwidth, estimate the CQI before a user transmits data because the sounding reference signal can be independent of the data transmitted by the user terminal, and obtain the more accurate CQI because the CQI estimation is performed according to the uplink channel information corresponding to the physical resources allocated to the user terminal for the next transmission.
Description
Technical Field
The present invention relates to the field of communications technologies, and in particular, to a method and an apparatus for performing Channel Quality Indicator (CQI) estimation in Multiple Input Multiple Output (MIMO).
Background
The transmission diversity technique of the MIMO system is to repeatedly transmit data stream after precoding at a transmitting end so as to obtain diversity gain and coding gain; the space multiplexing technology of the MIMO system is that a sending end sends a plurality of different data streams, thereby improving the capacity and the spectrum efficiency of the communication system by times under the condition of not increasing the bandwidth, really embodying the essence of improving the capacity of the MIMO system, but requiring the channel to be equivalent to a plurality of independent parallel sub-channels, thereby not generating interference among the data streams.
In uplink transmission, in order to achieve a higher peak rate, original User Equipment (UE) Single-antenna transmission, i.e., Single Input Multiple Output (SIMO), cannot meet the requirements of future communication development. Therefore, the uplink MIMO technology is an inevitable development, and is an important step in the Long-Term Evolution (LTE) to the Long-Term Evolution-Advanced (LTE-Advanced). In uplink MIMO technology, CQI estimation is an important part. The modulation coding mode transmitted by the UE side is determined by the CQI estimated value of the base station side, so that the lower error rate and the higher transmission rate are achieved. Therefore, the accuracy of the CQI estimation algorithm is crucial, and the throughput of the system is greatly affected.
At present, an uplink Single-user Multiple Input Multiple Output (SU-MIMO) has two modes, namely a closed-loop mode and an open-loop mode. The open loop SU-MIMO mode does not require feedback of channel information, and includes uplink transmit diversity, uplink open loop spatial multiplexing and other techniques. The closed loop SU-MIMO mode fully utilizes the feedback of the channel information, and adaptively adjusts the precoding matrix according to the channel information, thereby obtaining larger system capacity. The current closed-loop technology mainly includes a Codebook (Codebook) and a Non-Codebook (Non-Codebook). The former precoding matrix is selected in a codebook according to the channel information, and the latter precoding matrix is obtained by SVD (singular value decomposition) without the codebook according to the symmetry of the uplink and downlink channels. Regardless of the open-loop and closed-loop techniques, CQI estimation and Modulation and Coding Scheme (MCS) adjustment are performed.
However, no scheme discloses a method for performing CQI estimation in the SU-MIMO system at present, and some proposals use channel information obtained by demodulation pilot frequency estimation to perform CQI estimation. In this scheme, the base station performs CQI estimation by using the estimation result of the demodulation pilot, and since the demodulation pilot is transmitted together when the UE transmits data to the base station, this scheme can be implemented only when the UE transmits data, and since the CQI is obtained for the Physical resource used by the UE for the previous transmission, such as a sub-band CQI corresponding to some (Physical resource block, PRB) Physical resource block. If the base station adjusts the physical resources used by the UE and switches from a certain sub-band to another sub-band, the estimation result of the last demodulated CQI will have a large error because the actual CQI is different for different physical resources with different channel conditions. At this time, the selected MCS may be greatly biased, resulting in a decrease in system throughput.
Therefore, how to obtain the CQI estimation value as accurate as possible is a problem to be solved in the SU-MIMO system.
Disclosure of Invention
The invention aims to provide a method and a device for estimating CQI, which are used for realizing CQI estimation in a multi-input multi-output system.
The invention provides a method for estimating CQI, which is applied to a multi-input multi-output system and comprises the following steps:
performing uplink channel estimation according to a received sounding reference signal sent by a user terminal;
and scheduling the user terminal according to the uplink channel estimation result, allocating physical resources occupied by the next transmission to the user terminal, and performing CQI estimation according to the uplink channel information of each physical resource to obtain CQI.
An embodiment of the present invention provides an apparatus for performing CQI estimation in a mimo system, where the apparatus includes:
a channel estimation unit, configured to perform uplink channel estimation according to a received sounding reference signal sent by a user terminal;
a resource scheduling unit, configured to schedule the user terminal according to an uplink channel estimation result, and allocate physical resources occupied by next transmission to the user terminal;
and the channel quality estimation unit is used for carrying out CQI estimation according to the uplink channel information of each physical resource allocated to the user terminal.
The embodiment of the invention utilizes the detection reference signal sent by the user terminal to carry out uplink channel estimation; scheduling the user terminal according to the uplink channel estimation result, and distributing physical resources occupied by the next transmission for the user terminal; and performing CQI estimation according to the uplink channel information of each physical resource allocated to the user terminal.
In the embodiment of the invention, since the sounding reference signal sent by the user terminal can cover the whole bandwidth, the CQI of any sub-band can be estimated.
In addition, in the embodiment of the invention, the sounding reference signal is adopted to realize CQI estimation, and the sounding reference signal sent by the user terminal can be independent of data sent by the user terminal, so that the CQI can be estimated and obtained before the user terminal transmits the data, and the CQI can be provided for the user terminal to start transmitting the data.
The embodiment of the invention carries out CQI estimation according to the uplink channel information corresponding to the physical resource distributed for the next transmission of the user terminal, thereby obtaining more accurate CQI.
Drawings
FIG. 1 is a schematic flow chart of a method according to an embodiment of the present invention;
FIG. 2 is a schematic diagram of an apparatus according to an embodiment of the present invention;
fig. 3 is a diagram illustrating the performance comparison between CQI estimation and ideal non-delayed CQI estimation according to an embodiment of the present invention.
Detailed Description
In the embodiment of the invention, in an MIMO system, uplink channel estimation is carried out by using a Sounding reference signal sent by a user terminal; scheduling the user terminal according to the uplink channel estimation result, and distributing physical resources occupied by the next transmission for the user terminal; and performing CQI estimation according to the uplink channel information of each physical resource allocated to the user terminal. Then, the MCS level of the user terminal corresponding to the obtained CQI may be determined by the set correspondence between the CQI and the MCS level.
Here, the sounding reference signal may be transmitted by the ue to the base station at intervals. And, the user terminal can occupy the whole bandwidth or part of the bandwidth to send the sounding reference signal to the base station side.
The following describes a specific implementation scheme of the method of the present invention by taking an SU-MIMO system as an example, with reference to fig. 1.
Referring to fig. 1, a specific procedure for implementing estimation in an SU-MIMO system according to an embodiment of the present invention is as follows:
step 101: the user terminal sends sounding reference signals to the base station at intervals in the whole bandwidth or part of the bandwidth, such as: the user terminal sends a sounding reference signal to the base station once in 5 ms.
Step 102: the base station side carries out uplink channel estimation through the received sounding reference signal and schedules the user terminal according to an uplink channel estimation result so as to determine physical resources occupied by the user terminal in next transmission;
step 103: and the base station side carries out CQI estimation according to the determined uplink channel information of each physical resource.
In the embodiment of the invention, for different uplink SU-MIMO algorithms, CQI estimation methods are slightly different:
in the first case: for open loop SU-MIMO, the base station obtains CQI through EESM mapping directly according to the uplink channel information of physical resources allocated to the user terminal.
In the second case: for closed-loop SU-MIMO in the form of codebook, the base station selects a precoding matrix from the set codebook according to the uplink channel information of the physical resource allocated to the user terminal and a certain criterion to obtain a precoding index (PMI), and performs EESM mapping by using the channel information and the precoding matrix corresponding to the PMI to obtain CQI.
In the third case: for the closed-loop SU-MIMO in the form of non-codebook, the base station obtains a precoding matrix through Singular Value Decomposition (SVD) Decomposition of an uplink channel matrix according to uplink channel information of physical resources allocated to the user terminal, and performs Exponential Effective SIR Mapping (EESM) Mapping by using the channel information and the precoding matrix to obtain CQI.
Step 104: the base station side determines the MCS information of the user terminal corresponding to the obtained CQI through the set correspondence between the CQI and the MCS, such as: MCS level or an indication indicating the current coding scheme, etc.
Then, the base station side can inform the user terminal of the MCS information through the downlink channel, and inform the user terminal of the determined MCS information through the control signaling, and the user terminal can perform corresponding modulation coding on the uplink data to be transmitted to the base station according to the MCS information.
Referring to fig. 2, an apparatus for CQI estimation in a mimo system according to an embodiment of the present invention includes: channel estimation section 201, resource scheduling section 202, and channel quality estimation section 203. Wherein,
a channel estimation unit 201, configured to perform uplink channel estimation according to a received sounding reference signal sent by a user terminal;
a resource scheduling unit 202, configured to schedule the user terminal according to the uplink channel estimation result, and allocate physical resources occupied by next transmission to the user terminal;
a channel quality estimation unit 203, configured to perform CQI estimation according to uplink channel information of each physical resource allocated to the user terminal.
The apparatus may further comprise: and the MCS selecting unit is used for determining the MCS information of the user terminal corresponding to the estimated CQI according to the set corresponding relation between the CQI and the MCS and informing the MCS information to the user terminal.
When the MIMO system is a system using an open-loop single-user MIMO SU-MIMO mode, the channel quality estimation unit 203 may obtain the CQI through EESM mapping according to uplink channel information for allocating physical resources to the user terminal.
When the MIMO system is a closed-loop SU-MIMO system in the form of a codebook, the channel quality estimation unit may select a precoding matrix from the codebook according to uplink channel information of physical resources allocated to the ue to obtain a PMI, and perform EESM mapping by using the uplink channel information and the precoding matrix corresponding to the PMI to obtain a CQI.
When the MIMO system is a non-codebook closed-loop SU-MIMO system, the channel quality estimation unit may obtain a precoding matrix by SVD decomposition of the uplink channel information channel matrix according to uplink channel information of physical resources allocated to the user terminal, and perform EESM mapping using the channel information and the precoding matrix to obtain CQI.
Fig. 3 is a diagram illustrating the performance comparison between CQI estimation and ideal non-delayed CQI estimation according to an embodiment of the present invention. Referring to fig. 3, the embodiment of the present invention is applied to simulate the performance comparison between the CQI estimation method of the present invention and the ideal CQI estimation without delay under a 2 × 2 antenna array TU channel. As can be seen from fig. 3, under the condition of non-codebook, the performance loss of the CQI method of the present invention is smaller than that of the ideal CQI estimation result without delay; under the condition of a codebook, the performance loss is small by adopting the CQI and PMI estimation method.
It should be noted that the embodiments of the present invention have wide applicability, and are not only applicable to SU-MIMO under 2 × 2, but also applicable to any antenna array (for example, a polarization array), and data transmission under any MIMO antenna configuration. Meanwhile, the invention can also be used for CQI estimation of various uplink MIMO sending modes, and is not limited to the modes listed in the invention.
In the embodiment of the invention, the base station side carries out uplink channel estimation by using Sounding reference signals sent by the user terminal, schedules the user terminal according to an uplink channel estimation result, distributes physical resources occupied by next transmission for the user terminal, and carries out CQI estimation according to uplink channel information of each physical resource distributed for the user terminal.
In the embodiment of the invention, because the Sounding reference signal sent by the user terminal can cover the whole bandwidth, the CQI of any sub-band can be estimated. In addition, because the Sounding reference signal can be independent of the data sent by the user terminal, the embodiment of the present invention can estimate the CQI estimation size before the user transmits the data, and can provide the CQI for the user terminal to start transmitting the data. Because the embodiment of the invention estimates the uplink channel information corresponding to the physical resource distributed for the user terminal benzyl transmission, more accurate CQI can be obtained, and the MCS selection error is reduced. In the embodiment of the invention, the sending interval of the sounding reference signal can be reduced, so that the CQI error caused by time delay can be reduced. Meanwhile, in the embodiment of the invention, the corresponding CQI estimation algorithm can be selected in a self-adaptive manner according to different SU-MIMO modes, so that the method has great flexibility.
It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.
Claims (10)
1. A method for estimating Channel Quality Indicator (CQI) is applied to a multi-input multi-output system,
the method is characterized by comprising the following steps:
the base station carries out uplink channel estimation according to the received sounding reference signal sent by the user terminal;
the base station schedules the user terminal according to the uplink channel estimation result, allocates physical resources occupied by the next transmission to the user terminal, and performs CQI estimation according to uplink channel information of each physical resource allocated to the next transmission of the user terminal to obtain CQI;
and the base station determines MCS information of the user terminal corresponding to the estimated CQI according to the set corresponding relation between the CQI and the modulation coding scheme MCS, and informs the user terminal of the MCS information.
2. The method according to claim 1, wherein when the MIMO system is a system using open-loop single-user MIMO (SU-MIMO) mode, the performing CQI estimation according to uplink channel information of each physical resource comprises:
and obtaining CQI through index effective signal-to-interference ratio mapping (EESM) mapping according to the uplink channel information of the physical resource allocated to the user terminal.
3. The method according to claim 1, wherein when the MIMO system is a closed-loop SU-MIMO system in codebook form, the performing CQI estimation according to uplink channel information of each physical resource comprises:
and selecting a precoding matrix from a codebook according to uplink channel information of physical resources allocated to the user terminal to obtain a precoding index PMI, and carrying out EESM mapping by using the uplink channel information and the precoding matrix corresponding to the PMI to obtain a CQI.
4. The method of claim 1, wherein when the MIMO system is a system employing a non-codebook closed-loop SU-MIMO mode, the performing CQI estimation according to uplink channel information of each physical resource comprises:
and the base station decomposes the SVD through the singular value of the uplink channel information channel matrix according to the uplink channel information of the physical resource distributed to the user terminal to obtain a pre-coding matrix, and carries out EESM mapping by utilizing the channel information and the pre-coding matrix to obtain CQI.
5. The method of claim 1, wherein the sounding reference signal is transmitted to the base station side by the user equipment at intervals.
6. The method of claim 1, wherein the sounding reference signal is transmitted to the base station side by a user terminal occupying the whole bandwidth or a part of the bandwidth.
7. An apparatus for CQI estimation in a multiple-input multiple-output system, the apparatus comprising:
a channel estimation unit, configured to perform uplink channel estimation according to a received sounding reference signal sent by a user terminal;
a resource scheduling unit, configured to schedule the user terminal according to an uplink channel estimation result, and allocate physical resources occupied by next transmission to the user terminal;
a channel quality estimation unit, configured to perform CQI estimation according to uplink channel information of each physical resource allocated for next transmission by the user terminal;
and the MCS selecting unit is used for determining the MCS information of the user terminal corresponding to the estimated CQI according to the set corresponding relation between the CQI and the MCS and informing the MCS information to the user terminal.
8. The apparatus of claim 7, wherein when the MIMO system is a system employing open-loop single-user multiple-input multiple-output (SU-MIMO) mode,
and the channel quality estimation unit is used for obtaining the CQI through EESM mapping according to the uplink channel information of the physical resource allocated to the user terminal.
9. The apparatus of claim 7, wherein when the MIMO system is a closed loop SU-MIMO mode system in codebook form,
and the channel quality estimation unit is used for selecting a precoding matrix from a set codebook according to the uplink channel information of the physical resource allocated to the user terminal to obtain a precoding index PMI, and carrying out EESM mapping by using the uplink channel information and the precoding matrix corresponding to the PMI to obtain a CQI.
10. The apparatus of claim 7, wherein when the MIMO system is a system employing a closed loop SU-MIMO mode in a non-codebook form,
the channel quality estimation unit is used for obtaining a pre-coding matrix through SVD decomposition of the uplink channel information channel matrix according to the uplink channel information of the physical resource distributed to the user terminal, and carrying out EESM mapping by using the channel information and the pre-coding matrix to obtain CQI.
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| Publication number | Priority date | Publication date | Assignee | Title |
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| US8675558B2 (en) * | 2011-01-07 | 2014-03-18 | Intel Corporation | CQI definition for transmission mode 9 in LTE-advanced |
| CN102624481A (en) * | 2011-01-31 | 2012-08-01 | 中兴通讯股份有限公司 | Self-adaptive modulation and coding method and apparatus |
| CN102291839B (en) * | 2011-08-16 | 2014-07-09 | 电信科学技术研究院 | Method and device for transmitting CQI (channel quality indicator) information |
| CN102437899B (en) * | 2011-12-19 | 2015-03-11 | 电信科学技术研究院 | Method and device for determining uplink CQI (Channel Quality Indicator) value |
| CN103905101B (en) * | 2012-12-27 | 2019-02-12 | 中兴通讯股份有限公司 | Method and base station for determining downlink precoding granularity in LTE system |
| CN103650400B (en) * | 2013-08-21 | 2017-06-13 | 华为技术有限公司 | A kind of method, the apparatus and system of selection pre-coding matrix instruction |
| CN107733496A (en) * | 2016-08-12 | 2018-02-23 | 华为技术有限公司 | Data transmission method for uplink, signaling method, apparatus and system |
| CN109787667B (en) * | 2017-11-12 | 2020-06-30 | 上海朗帛通信技术有限公司 | Method and device used in user equipment and base station for wireless communication |
| WO2019161547A1 (en) | 2018-02-23 | 2019-08-29 | Oppo广东移动通信有限公司 | Dynamic configuration method, terminal device, network device and computer storage medium |
| WO2020000265A1 (en) * | 2018-06-27 | 2020-01-02 | 华为技术有限公司 | Method for selecting transmission mode, and communication device |
| CN113965291B (en) * | 2020-07-20 | 2024-05-17 | 中兴通讯股份有限公司 | Communication control method, base station, terminal and storage medium |
| CN115119291A (en) * | 2021-03-23 | 2022-09-27 | 瑞昱半导体股份有限公司 | Wireless communication device and method |
| CN116418424A (en) * | 2021-12-31 | 2023-07-11 | 展讯通信（上海）有限公司 | Channel quality indication calculation or acquisition method and device, terminal and network equipment |
| WO2023227046A1 (en) * | 2022-05-27 | 2023-11-30 | 上海朗帛通信技术有限公司 | Method and apparatus for wireless communication |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1613201A (en) * | 2001-11-06 | 2005-05-04 | 高通股份有限公司 | Multiple-access multiple-input multiple-output (MIMO) communication system |
| TW200625851A (en) * | 2004-09-10 | 2006-07-16 | Intel Corp | Interpolation in channel state feedback |
| EP1780925A2 (en) * | 2005-10-31 | 2007-05-02 | Samsung Electronics Co., Ltd. | Multiple antenna communication system using spatial pre-coding |
| CN101142748A (en) * | 2005-03-14 | 2008-03-12 | 摩托罗拉公司 | Low-feedback scheme for link-quality reporting based on the exp-esm technique |
-
2008
- 2008-09-26 CN CN 200810223363 patent/CN101686214B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1613201A (en) * | 2001-11-06 | 2005-05-04 | 高通股份有限公司 | Multiple-access multiple-input multiple-output (MIMO) communication system |
| TW200625851A (en) * | 2004-09-10 | 2006-07-16 | Intel Corp | Interpolation in channel state feedback |
| CN101142748A (en) * | 2005-03-14 | 2008-03-12 | 摩托罗拉公司 | Low-feedback scheme for link-quality reporting based on the exp-esm technique |
| EP1780925A2 (en) * | 2005-10-31 | 2007-05-02 | Samsung Electronics Co., Ltd. | Multiple antenna communication system using spatial pre-coding |
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