CN101753186A - Channel quality information estimating method used for transmitting multi-flow beam forming data - Google Patents
Channel quality information estimating method used for transmitting multi-flow beam forming data Download PDFInfo
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Abstract
The embodiment of the invention discloses a channel quality information CQI estimating method used for transmitting multi-flow beam form data, which comprises the following steps that: a terminal estimates the channel matrix H from a base station to the terminal according to received common pilot signals; the terminal estimates one or a plurality of CQI information according to the number of the common pilot ports sending the common pilot signals and the number of data streams transmitted by multi-flow beam forming by the channel matrix H. More than two CQI informations can be estimated by applying the invention, and the invention is suitable for transmitting the multi-flow beam form data.
Description
Technical field
The present invention relates to communication technical field, relate in particular to a kind of channel quality (Channel Quality Indicating, CQI) information estimating method that is used for the multi-flow beam forming transfer of data.
Background technology
In Long Term Evolution (LTE) system, base station side is when carrying out the wave beam forming transfer of data, at first need end side to estimate CQI information, end side is given the base station with the CQI feedback information that estimates, the CQI information that feed back according to the figuration gain compensating parameter and the end side of acquisition this base station obtains to be used for the actual CQI information of wave beam forming transfer of data, carries out the wave beam forming transfer of data according to this actual CQI information then.
Wherein, the method that terminal estimates CQI information is: according to the pilot signal calculation base station of the public guide frequency port channel matrix H to terminal, determine that according to the public guide frequency port number CQI information estimates mode by terminal.Particularly, when the public guide frequency port was single port, terminal used high specific merging method to calculate CQI information; When the public guide frequency port was multiport, terminal was estimated CQI information according to diversity mode, and the number of the CQI information that its estimation obtains is 1.
In the multi-flow beam forming transfer of data, the needed CQI information of each beamforming data stream is different, and existing according to diversity mode channel matrix H calculated the method for estimating CQI information and only can estimate 1 CQI information, therefore, the method for existing this estimation CQI information is not suitable for the multi-flow beam forming transfer of data.
Summary of the invention
In view of this, the object of the present invention is to provide a kind of CQI information estimating method that is used for the multi-flow beam forming transfer of data, can estimate a plurality of CQI information at a plurality of data flow in the multi-flow beam forming transfer of data, make the CQI information that estimates be applicable to multi-flow beam forming.
For achieving the above object, technical scheme of the present invention specifically is achieved in that
A kind of channel quality CQI information estimating method that is used for the multi-flow beam forming transfer of data, this method comprises:
Terminal estimates the channel matrix H of base station to terminal according to the common pilot signal that receives;
Terminal estimates one or more CQI information according to the public guide frequency port number that sends described common pilot signal and the multi-flow beam data flow number of multi-flow beam forming by channel matrix H.
Describedly estimate one or more CQI information by channel matrix H and comprise:
Terminal is determined the number of this terminal to the CQI of base station feedback information according to the public guide frequency port number that sends described common pilot signal and the multi-flow beam data flow number of multi-flow beam forming;
In the number of described CQI information when being a plurality of, correlation matrix to channel matrix H carries out characteristic value decomposition, go out CQI information by characteristic value that decomposites and characteristic of correspondence vector, perhaps, select pre-coding matrix and channel matrix H to multiply each other and obtain equivalent matrix G, estimate CQI information by equivalent matrix G.
As seen from the above technical solution, because end side of the present invention is when estimating CQI information according to channel matrix H, need can estimate a plurality of CQI information to the CQI information estimating method that the CQI of base station feedback information adopts when being a plurality of in terminal, make the CQI information that estimates be applicable to the multi-flow beam forming transfer of data.
Description of drawings
Fig. 1 is the CQI information estimating method flow chart that is used for the multi-flow beam forming transfer of data provided by the invention.
Embodiment
For making purpose of the present invention, technical scheme and advantage clearer, below with reference to the accompanying drawing embodiment that develops simultaneously, the present invention is described in more detail.
CQI information estimating method provided by the invention is based on common pilot signal and estimates CQI information, and its concrete method of estimation sees Fig. 1 and related description for details.
Fig. 1 is the CQI information estimating method flow chart that is used for the multi-flow beam forming transfer of data provided by the invention, and as shown in Figure 1, this method comprises:
In this step, terminal estimates the channel matrix H of base station to terminal according to the common pilot signal that receives.
Wherein, channel matrix H is the matrix of the capable L row of R, and the capable j column element of i of channel matrix H is the Channel Transmission coefficient of base station public port j to terminal reception antenna i.Wherein, R is the public guide frequency port number of base station, and L is the antenna number of terminal.
In this step, send according to reality among the multi-flow beam data flow number S of the public guide frequency port number P of described common pilot signal and multi-flow beam forming and determine the number N of this terminal to the CQI of base station feedback information.Particularly, preferentially determine the number N of CQI information, send the public guide frequency port number P of described common pilot signal when not enough, select big as far as possible N according to P in reality according to multi-flow beam data flow number S.Usually, a less side is defined as the number of this terminal to the CQI of base station feedback information in the public guide frequency port number of described common pilot signal and the multi-flow beam data flow number with sending, promptly N=min (P, S).
For example, for the transmission of the dual-stream beamforming of S=2, if P=1, if N=1 then is P＞1, then N=2.
In this step, the public guide frequency port number that sends described common pilot signal by terminal to Physical Broadcast Channel (Physic Broadcast Channel, PBCH) information detects and obtains, this belongs to prior art.
In the number of CQI information when being a plurality of, correlation matrix to channel matrix H carries out characteristic value decomposition, go out CQI information by characteristic value that decomposites and characteristic of correspondence vector, perhaps, select pre-coding matrix and channel matrix H to multiply each other and obtain equivalent matrix G, estimate CQI information by equivalent matrix G.
Wherein, the correlation matrix of channel matrix H is meant the multiply each other matrix of gained of the transpose conjugate of channel matrix H and this channel matrix H.
Wherein, select pre-coding matrix and the channel matrix H method that obtains equivalent matrix G that multiplies each other to be: each pre-coding matrix and channel matrix H are multiplied each other, with the result of product of mould value maximum in each result of product as equivalent matrix G.
If the public guide frequency port number is 1, also, the number of CQI information is 1, and then, terminal adopts methods such as high specific merging or geometric ratio merging to calculate CQI information.
If the public guide frequency port number is 2 or 4, then preferentially estimate CQI information according to equivalent matrix G, also can carry out characteristic value decomposition to equivalent matrix H, go out CQI information by characteristic value that decomposites and characteristic of correspondence vector.
If the public guide frequency port number is 8, then preferentially equivalent matrix H is carried out characteristic value decomposition, go out CQI information by characteristic value that decomposites and characteristic of correspondence vector, also can estimate CQI information according to equivalent matrix G.
Wherein, equivalent matrix H is carried out characteristic value decomposition, the method that is gone out CQI information by characteristic value that decomposites and characteristic of correspondence vector is: the correlation matrix to described channel matrix H carries out characteristic value decomposition, number N according to described CQI information chooses the individual characteristic value of N, go out each signal to noise ratio snr by each characteristic value and characteristic of correspondence vector, estimate each CQI information according to each SNR.Wherein, the characteristic value of choosing is the characteristic value of N position before coming according to descending order.
Equivalence matrix G estimate CQI information method can for: estimate each signal to noise ratio snr by equivalent matrix G, estimate each CQI information according to each SNR.Particularly, can calculate equivalent matrix G and the conjugate matrices G of himself
HFirst product, with the inverse matrix and the noise variance σ of first result of product
2Multiplying each other obtains second product, chooses the diagonal entry of similar number according to the number of described CQI information from second result of product, with the inverse of each diagonal entry as corresponding C QI information.
In this step, terminal can be calculated CQI information based on the broadband according to the notice of base station, also can calculate CQI information based on subband according to the notice of base station, and wherein the concrete scope of broadband and subband is made an appointment by terminal and base station and obtained.
In this step, described feedback system can be a periodic feedback, also can be non-periodic feedback.
In this step, the actual CQI information of each data flow is calculated in the base station according to the figuration gain of described CQI information and each CQI information corresponding data stream.
The figuration gain of described each CQI information corresponding data stream can be to obtain initial value by network test in advance, and this initial value is kept in the base station, and the base station obtains this initial value according to the actual Block Error Rate adjustment that records in the communication process and obtains.
In this step, frequency domain dispatching is carried out according to described actual CQI information and selects modulation coding mode that (Modulate coding scheme, MCS) grade are carried out downlink multi-stream wave beam forming transfer of data according to the MCS grade of frequency domain dispatching result and selection in the base station.
As seen from the above technical solution, because end side of the present invention is when estimating CQI information according to channel matrix H, according to public guide frequency port number and multi-flow beam data flow number, adopted different CQI information estimating methods, wherein, port number be 2,4 or the CQI information estimating method that adopted in 8 o'clock can estimate plural CQI information, therefore, CQI information estimating method provided by the invention can be applied to multi-flow beam forming.
The above is preferred embodiment of the present invention only, is not to be used to limit protection scope of the present invention, all any modifications of being made within the spirit and principles in the present invention, is equal to replacement, improvement etc., all should be included within protection scope of the present invention.
Claims (10)
1. channel quality CQI information estimating method that is used for the multi-flow beam forming transfer of data is characterized in that this method comprises:
Terminal estimates the channel matrix H of base station to terminal according to the common pilot signal that receives;
Terminal estimates one or more CQI information according to the public guide frequency port number and the multi-flow beam forming data flow transmitted number that send described common pilot signal by channel matrix H.
2. the method for claim 1 is characterized in that, describedly estimates one or more CQI information by channel matrix H and comprises:
Terminal is determined the number of this terminal to the CQI of base station feedback information according to the public guide frequency port number and the multi-flow beam forming data flow transmitted number that send described common pilot signal;
In the number of described CQI information when being a plurality of, correlation matrix to channel matrix H carries out characteristic value decomposition, go out CQI information by characteristic value that decomposites and characteristic of correspondence vector, perhaps, select pre-coding matrix and channel matrix H to multiply each other and obtain equivalent matrix G, estimate CQI information by equivalent matrix G.
3. method as claimed in claim 2 is characterized in that, described selection pre-coding matrix and channel matrix H multiply each other and obtain equivalent matrix G and be:
Each pre-coding matrix and channel matrix H are multiplied each other, with the result of product of mould value maximum in each result of product as equivalent matrix G.
4. method as claimed in claim 2 is characterized in that, described definite this terminal comprises to the number of the CQI of base station feedback information:
A less side is defined as the number of this terminal to the CQI of base station feedback information in the fluxion of the public guide frequency port number of described common pilot signal and multi-flow beam transfer of data with sending.
5. method as claimed in claim 2, it is characterized in that, in the number of described CQI information when being a plurality of, correlation matrix to channel matrix H carries out characteristic value decomposition, go out CQI information by characteristic value that decomposites and characteristic of correspondence vector, perhaps, select pre-coding matrix and channel matrix H to multiply each other and obtain equivalent matrix G, estimate CQI information by equivalent matrix G and comprise:
At the public guide frequency port number that sends described common pilot signal is 2 or 4 o'clock, selects pre-coding matrix and channel matrix H to multiply each other and obtains equivalent matrix G, estimates CQI information by equivalent matrix G.
6. method as claimed in claim 2, it is characterized in that, in the number of described CQI information when being a plurality of, correlation matrix to channel matrix H carries out characteristic value decomposition, go out CQI information by characteristic value that decomposites and characteristic of correspondence vector, perhaps, select pre-coding matrix and channel matrix H to multiply each other and obtain equivalent matrix G, estimate CQI information by equivalent matrix G and comprise:
At the public guide frequency port number that sends described common pilot signal is 8 o'clock, and the correlation matrix of channel matrix H is carried out characteristic value decomposition, goes out CQI information by characteristic value that decomposites and characteristic of correspondence vector.
7. as claim 2 or 5 or 6 described methods, it is characterized in that,
Described correlation matrix to channel matrix H carries out characteristic value decomposition, goes out CQI information by characteristic value that decomposites and characteristic of correspondence vector and comprises:
Correlation matrix to described channel matrix H carries out characteristic value decomposition, choose the characteristic value of similar number according to the number of described CQI information, go out the signal to noise ratio snr of each data flow correspondence by each characteristic value and characteristic of correspondence vector, estimate the CQI information of each data flow correspondence according to SNR.
8. as claim 2 or 5 or 6 described methods, it is characterized in that, describedly estimate CQI information by equivalent matrix G and comprise:
Estimate the signal to noise ratio snr of each data flow correspondence by equivalent matrix G, estimate the CQI information of each data flow correspondence according to SNR.
9. as the described method of the arbitrary claim of claim 1 to 6, it is characterized in that this method further comprises:
Terminal is given the base station with described CQI feedback information;
The figuration gain that flow according to described CQI information and each CQI information corresponding data the base station calculates the actual CQI information of each data flow, carries out the multi-flow beam forming transfer of data according to described actual CQI information.
10. method as claimed in claim 9 is characterized in that, carries out the multi-flow beam forming transfer of data according to described actual CQI information and comprises:
Carry out frequency domain dispatching and select the MCS grade according to described actual CQI information, carry out downlink multi-stream wave beam forming transfer of data according to the MCS grade of frequency domain dispatching result and selection.
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| CN102149130A (en) * | 2011-04-22 | 2011-08-10 | 电信科学技术研究院 | Method, device and system for reporting channel quality indicator |
| WO2012059000A1 (en) * | 2010-11-05 | 2012-05-10 | 大唐移动通信设备有限公司 | Method and device for reporting channel quality information |
| CN103634071A (en) * | 2012-08-27 | 2014-03-12 | 华为技术有限公司 | Pre-coding matrix selection method, device and system |
| CN105917609A (en) * | 2014-12-23 | 2016-08-31 | 华为技术有限公司 | Channel measurement and feedback method, network device, and system |
| WO2018157318A1 (en) * | 2017-02-28 | 2018-09-07 | 华为技术有限公司 | Scheduling method, base station and terminal |
| CN111835474A (en) * | 2019-04-19 | 2020-10-27 | 大唐移动通信设备有限公司 | PBCH-based signal processing method and device |
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| WO2012059000A1 (en) * | 2010-11-05 | 2012-05-10 | 大唐移动通信设备有限公司 | Method and device for reporting channel quality information |
| CN102469496A (en) * | 2010-11-05 | 2012-05-23 | 大唐移动通信设备有限公司 | Method and device for reporting channel quality information |
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| CN102469496B (en) * | 2010-11-05 | 2014-12-17 | 大唐移动通信设备有限公司 | Method and device for reporting channel quality information |
| CN102149130A (en) * | 2011-04-22 | 2011-08-10 | 电信科学技术研究院 | Method, device and system for reporting channel quality indicator |
| CN102149130B (en) * | 2011-04-22 | 2014-01-01 | 电信科学技术研究院 | Method, device and system for reporting channel quality indicator |
| US9252932B2 (en) | 2011-04-22 | 2016-02-02 | China Academy Of Telecommunications Technology | Method, device, and system for reporting channel quality indicator |
| CN103634071B (en) * | 2012-08-27 | 2017-04-12 | 华为技术有限公司 | Pre-coding matrix selection method, device and system |
| CN103634071A (en) * | 2012-08-27 | 2014-03-12 | 华为技术有限公司 | Pre-coding matrix selection method, device and system |
| CN105917609A (en) * | 2014-12-23 | 2016-08-31 | 华为技术有限公司 | Channel measurement and feedback method, network device, and system |
| US10454537B2 (en) | 2014-12-23 | 2019-10-22 | Huawei Technologies Co., Ltd. | Channel measurement and feedback method, network device, and system |
| US10951276B2 (en) | 2014-12-23 | 2021-03-16 | Huawei Technologies Co., Ltd. | Channel measurement and feedback method, network device, and system |
| WO2018157318A1 (en) * | 2017-02-28 | 2018-09-07 | 华为技术有限公司 | Scheduling method, base station and terminal |
| CN110337824A (en) * | 2017-02-28 | 2019-10-15 | 华为技术有限公司 | A kind of method of scheduling, base station and terminal |
| CN110337824B (en) * | 2017-02-28 | 2020-12-18 | 华为技术有限公司 | Scheduling method, base station and terminal |
| US11044000B2 (en) | 2017-02-28 | 2021-06-22 | Huawei Technologies Co., Ltd. | Scheduling method, base station, and terminal |
| CN111835474A (en) * | 2019-04-19 | 2020-10-27 | 大唐移动通信设备有限公司 | PBCH-based signal processing method and device |
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