CN101378282A - Method and apparatus for processing signal of multi-input multi-output system - Google Patents
Method and apparatus for processing signal of multi-input multi-output system Download PDFInfo
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- CN101378282A CN101378282A CNA200710147627XA CN200710147627A CN101378282A CN 101378282 A CN101378282 A CN 101378282A CN A200710147627X A CNA200710147627X A CN A200710147627XA CN 200710147627 A CN200710147627 A CN 200710147627A CN 101378282 A CN101378282 A CN 101378282A
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Abstract
The invention relates to a signal processing method and the device of a multi-input and multi-output system, wherein, the device comprises first-time precoding modules (112.1, 112.2) which are positioned at a transmitting terminal and connected with unified channel decomposing modules (113.1, 113.2) at the transmitting terminal, and a second-time precoding module connected with a block diagonalization processing module (116), and also comprises receiving terminal unified channel decomposing modules (121.1, 121.2) positioned between channel estimation modules (120.1, 120.2) and detection modules (118.1, 118.2) at a receiving terminal; wherein, the method comprises the following steps: a multi-user multi-input and multi-output physical channel is decomposed into a plurality of independent single user virtual channels; unified channel decomposition is carried out to the original pre-transmitting signals of each user by utilizing the virtual channel; block diagonalization processing is carried out to the decomposed signals and the signals are transmitted to the outside by an antenna array; and the receiving terminal is combined with the unified channel decomposition to detect the original pre-transmitting signals.
Description
Technical field
(Multiple-Input Multiple-Out-put, MIMO) technology are specifically related to a kind of multi-input and multi-output system signal processing method and device to the present invention relates to multiple-input and multiple-output.
Background technology
Multiple-input and multiple-output (MIMO) technology has become one of key technology of next generation wireless communication system.At present, the research of mimo system has expanded to the multi-user MIMO system of point-to-multipoint from point-to-point single user system.Many antenna configurations of multi-user are brought many benefits: the diversity gain that many antennas have can improve the bit error rate characteristic, and the spatial multiplexing gain of many antennas can make multi-user's channel capacity zone enlarge.Multi-user MIMO system has two subject matters in application: Mulitiple user resource scheduling and multi-user interference are eliminated.Owing between same user's different antennae and the channel condition difference between different user, need do rational management to system resource in order to obtain heap(ed) capacity.Using the multi-user MIMO system of unified frequency range can use various access modes aspect the multi-user interference elimination, the spectrum efficiency of time division multiple access is low, and power system capacity is not high, and code division multiple access need consume a large amount of sign indicating number resources.The space division multiple access technique availability of frequency spectrum is high and do not consume a yard resource, is a kind of important way of multiuser MIMO, and combining with other multi-access modes further improves the flexibility of system applies.
Based on the unified channel decomposing Uniform Channel Decomposition feedback channel model of (being called for short UCD), adopt unified transmission and received signal processing mode at transmitting terminal and receiving terminal, as using VBLAST decoding or ZF Dirty Paper precoding.The method that channel UCD decomposes is that mimo channel is decomposed into signal to noise ratio (Signal to Noise Ratio, SNR) an identical L subchannel, we just can adopt unified power division and modulation scheme to each subchannel like this, not only reduce the complexity of system but also improved the performance of system, and do not have the performance of present additive method and a trade-off problem of capacity: during high dB, this method can make performance and maximum capacity.
Above-mentioned UCD method only has good optimization effect to the Single User MIMO system, and in multi-user MIMO system, owing to can't obtain mutual channel information between inter-user interference and the different user, the UCD method is difficult to direct use, and the UCD method of suitable multi-user MIMO system or such method are not disclosed at present.In addition, the Chinese patent application " a kind of multi-input and multi-output system signal processing method and device " submitted to simultaneously of the present patent application people provides a kind of multi-user UCD method based on channel reverse processing.
Summary of the invention
The technical issues that need to address of the present invention provide a kind of multi-input and multi-output system signal processing method and device, in multi-user's actual environment, avoid the trade-off problem of performance and capacity, the complexity of system can be reduced, the performance of system can be improved simultaneously again.
Above-mentioned first technical problem of the present invention solves like this, and a kind of mimo system signal processing method is provided, and may further comprise the steps:
1.1) adopt the block diagonalization method that multiuser MIMO physical channel H is resolved into independently a plurality of single user virtual channels h
1, h
2
1.2) transmitting terminal according to each virtual channel matrix to the original pre-sent signal X of corresponding each user
1, X
2Carry out unified channel decomposing and generate secondary pre-sent signal F separately
1X
1, F
2X
2
1.3) transmitting terminal is to all secondary pre-sent signal F
1X
1, F
2X
2The unified block diagonalization that carries out is handled M * [(F
1X
1)
T, (F
2X
2)
T] T and outwards launch by aerial array, wherein superscript T represents the conjugate transpose computing.
A kind of multi-user UCD method of handling based on block diagonalization is provided like this.
According to processing method provided by the invention, this processing method comprises also that each user terminal carries out channel estimating according to its received signal and with the respective channels matrix H
1, H
2Feed back to the base station, the base station is according to described respective channels matrix H
1, H
2Obtain described multiuser MIMO physical channel H=[(H
1)
T(H
2)
T]
T
According to processing method provided by the invention, this processing method also comprise the base station by pilot signal with described pseudo channel h
1, h
2Send to each user terminal.
According to processing method provided by the invention, described transmission is when described feedback is arranged or described multiuser MIMO physical channel carries out when changing, such as: can send once by every 5ms, reduce taking bandwidth.
According to processing method provided by the invention, described step 1.2) unified channel decomposing comprises according to each pseudo channel h in
1, h
2Generate and utilize respective user pre-coding matrix F
1, F
2To the original pre-sent signal X of corresponding each user
1, X
2Handle F
1X
1, F
2X
2
According to processing method provided by the invention, described step 1.3) block diagonalization is handled and is comprised according to described multiuser MIMO physical channel H and generate and utilize block diagonalization pre-coding matrix M to all secondary pre-sent signal F in
1X
1, F
2X
2The unified M * [(F that handles
1X
1)
T, (F
2X
2)
T]
T
According to processing method provided by the invention, the block diagonalization matrix M is k user's pre-coding matrix M
kLevel splicing, that is: M=[M
1M
k].The channel matrix of considering all users is in transmitting terminal known situation fully, and requires the precoding of transmitting terminal to make not have other user's interference, then each user's pre-coding matrix M in each user's the received signal
i, i=1 ... k need satisfy: H
iM
j=0, i ≠ j wherein, promptly each user's pre-coding matrix is positioned at the kernel of other all users' channel matrix, and condition can be tried to achieve k user's pre-coding matrix M in view of the above
k
Press H=[(H
1)
T(H
k)
T]
TIf select the row of Fk to be positioned at
Kernel, then the block diagonalization condition just can satisfy, here
Be that the channel matrix that whole channel matrix H is removed corresponding to user k obtains.
According to processing method provided by the invention, this processing method also comprises:
7.1) receiving terminal is according to received signal Y separately
1Or Y
2Estimate self channel H
1Or H
2
7.2) detect corresponding described original pre-sent signal X in conjunction with unified channel decomposing
1Or X
2
According to processing method provided by the invention, described detection is that least mean-square error (Minimum MeanSquare Error MMSE) detects described step 1.2) comprises described pseudo channel h
1, h
2Carry out unified channel decomposing and obtain and utilize MMSE weight detection matrix W
1Or W
2To described received signal Y
1Or Y
2Detect.
According to processing method provided by the invention, receiving terminal uses receiving antenna array.
According to processing method provided by the invention, described detection includes, but are not limited to MMSE and detects.
According to processing method provided by the invention, described multi-user is more than two or two.
According to processing method provided by the invention, described aerial array comprises a plurality of antennas.
Above-mentioned another technical problem of the present invention solves like this, and a kind of mimo system signal processing apparatus is provided, and comprising:
Transmitting terminal, comprise the modulation module, first-time precoding module, secondary precoding module and the transmitting antenna array that connect successively, wherein: first-time precoding module is connected with the transmitting terminal unified channel decomposing module, the secondary precoding module is connected with the block diagonalization processing module, and the output of block diagonalization processing module connects the transmitting terminal unified channel decomposing module;
Receiving terminal, comprise the receiving antenna array, detection module and the demodulation module that connect successively, wherein: receiving antenna array is connected with channel estimation module, and detection module is connected with the receiving terminal unified channel decomposing module, and channel estimation module output connects the receiving terminal unified channel decomposing module.
According to processing unit provided by the invention, described detection module can be MMSE detection module, ZF ZF detection module etc.
According to processing unit provided by the invention, described aerial array comprises a plurality of antennas.
Multi-input and multi-output system signal processing method provided by the invention and device, by the block diagonalization processing multiuser MIMO physical channel is decomposed into independently a plurality of single user virtual channels, be suitable for for each independently single user virtual channels thereby make based on unified channel decomposing, compared following advantage with prior art: first, utilize the characteristic of communication channel to carry out channel reverse processing, can eliminate inter-user interference, thereby make multi-input multi-output system have adaptability widely; The second, utilize the unified channel decomposing method to optimize each user's performance.This method is succinct, calculating is quick, is easy to Project Realization.
Description of drawings
Further the present invention is described in detail below in conjunction with the drawings and specific embodiments.
Fig. 1 is apparatus of the present invention structural representations.
Fig. 2 is the inventive method schematic flow sheet;
Fig. 3 is multi-input multi-output system simulated effect figure of the present invention.
Embodiment
Below, be example explanation the present invention with two users' multi-input multi-output system:
(1) device
As shown in Figure 1, this system comprises transmitting terminal and receiving terminal and feedback path 122.1,122.2, and apparatus of the present invention comprise:
Transmitting terminal comprises: information source module 110.1,110.2, modulation module 111.1,111.2, first-time precoding module 112.1,112.2, UCD decomposing module 113.1,113.2, block diagonalization processing module 114, secondary precoding module 115, and N
t Individual transmitting antenna 116;
Receiving terminal comprises: N
R1, N
R2Individual reception antenna 117.1,117.2, MMSE detection module 118.1,118.2, demodulation module 119.1,119.2, channel estimation module 120.1,120.2, UCD decomposing module 121.1,121.2.And feedback path 122.1,122.2
At transmitting terminal, 114 pairs of multiuser MIMO physical channels of channel reverse processing module carry out block diagonalization to be handled, and the multiuser MIMO physical channel is divided into independently two single user virtual channels h
1, h
2Output to UCD decomposing module 113.1,113.2 respectively; UCD decomposing module 113.1,113.2 decomposites user's pre-coding matrix F of two users respectively
1, F
2Block diagonalization processing module 114 is gone back the IOB diagonalization and is handled pre-coding matrix M simultaneously, and then secondary precoding module 115 is carried out the secondary precoding processing according to block diagonalization processing pre-coding matrix M.
At receiving terminal, 120.1,120.2 couples of N of channel estimation module
R1, N
R2The signal of individual reception antenna 117.1,117.2 is estimated, the channel information that estimates is outputed to UCD decomposing module 121.1,121.2 respectively, and the channel matrix H of user 1, user's 2 correspondences
1, H
2Feed back to receiving terminal through feedback path 122.1,122.2 respectively.UCD decomposing module 121.1,121.2 decomposites two users' weighting matrix W respectively
1, W
2, and being sent to MMSE detection module 118.1,118.2, the detection that participates in signal is handled.For signal detection module, present embodiment adopts the MMSE detection module, can also use the signal detection module of other types certainly in the practical application.
(2) operation principle
As shown in Figure 2, the concrete enforcement of the inventive method may further comprise the steps:
201) receiving terminal channel estimating: generate channel quality measurements information by channel estimating, generally the forms such as total signal to noise ratio snr with link provide.Provide the channel matrix of reflection channel characteristics simultaneously, this channel matrix comprises every pair and transmits and receives channel response relation between the antenna.
202) channel condition information feedback: obtain the channel matrix of reflection channel characteristics of the link of receiving terminal channel estimation feedback, according to the SNR selecting modulation mode, processing mode when determining that according to channel matrix system is empty.
203) the multiuser MIMO channel being carried out diagonalization handles.
Suppose that H is k user's a channel matrix H
kVertical splicing, M is k user's pre-coding matrix M
kLevel splicing, promptly
H＝[(H
1)
T…(H
k)
T]
T
M＝[M
1…M
k]
Wherein superscript T represents the conjugate transpose computing, if select F
kRow be positioned at
Kernel, then the block diagonalization condition just can satisfy.Here
Be that the channel matrix that whole channel matrix H is removed corresponding to user k obtains.
The channel matrix of considering all users is in transmitting terminal known situation fully, and requires the precoding of transmitting terminal to make not have other user's interference, then each user's pre-coding matrix M in each user's the received signal
i, i=1 ... k need satisfy: H
iM
j=0, i ≠ j wherein, promptly each user's pre-coding matrix is positioned at the kernel of other all users' channel matrix, and condition can be tried to achieve k user's pre-coding matrix M in view of the above
k
204) block diagonalization is exported h
1, h
2Carry out unified channel decomposing, obtain two users' pre-coding matrix F
1, F
2
After diagonalization was handled, the multiuser MIMO channel was divided into independently two Single User MIMO channel h
1, h
2,, just can't estimate current pseudo channel h alone owing to can't work in coordination with between the user
1, h
2So next the base station will increase the frequency pilot sign emission of once passing through the M precoding, makes the user know h
1, h
2Last base station and user are respectively to h
1, h
2Carry out UCD and decompose, obtain two users' pre-coding matrix F
1, F
2With MMSE weight detection matrix W
1, W
2
205), carry out precoding processing according to diagonalization pre-coding matrix M.
(3) emulation
As shown in Figure 3, the inventive method has been compared in emulation in different correlation channels: block diagonalization-unified channel decomposing BD-UCD and existing method: ZF (Zero-forcing ZF, the ZF method can be referring to [Quentin H.Spencer, A.Lee Swindlehurst, Martin Haardt.Zero-forcingMethods for Downlink Spatial Multiplexing in Multiuser MIMO Channels.IEEETransactions on Signal Processing, 2004,52 (2)] error rate BER) supposes that here new road coefficient correlation is respectively 0.1 and 0.7, and simulation result shows that BD-UCD of the present invention more can adapt to the channel condition of high correlation than ZF.
Claims (10)
1, a kind of multi-input and multi-output system signal processing method is characterized in that, may further comprise the steps:
1.1) adopt the block diagonalization method that multi-user's multiple-input and multiple-output physical channel is resolved into independently a plurality of single user virtual channels;
1.2) transmitting terminal carries out unified channel decomposing according to each virtual channel matrix to the original pre-sent signal of corresponding each user and generate secondary pre-sent signal separately;
1.3) transmitting terminal carries out to all secondary pre-sent signal unifications that block diagonalization is handled and outwards launch by aerial array.
2, according to the described processing method of claim 1, it is characterized in that, this processing method comprises that also each user terminal carries out the respective channels estimation and feeds back to the base station according to its received signal, and the base station obtains described multi-user's multiple-input and multiple-output physical channel according to described respective channels.
According to the described processing method of claim 2, it is characterized in that 3, this processing method comprises that also the base station sends to each user terminal by pilot signal with described pseudo channel.
According to the described processing method of claim 3, it is characterized in that 4, described transmission is when described feedback is arranged or described multi-user's multiple-input and multiple-output physical channel carries out when changing.
5, according to the described processing method of claim 1, it is characterized in that described step 1.2) in unified channel decomposing comprise according to each pseudo channel and generate and utilize the respective user pre-coding matrix that the original pre-sent signal of corresponding each user is handled.
6, according to the described processing method of claim 1, it is characterized in that described step 1.3) in block diagonalization handle and to comprise according to described multi-user's multiple-input and multiple-output physical channel and generate and utilize the diagonalization pre-coding matrix that all secondary pre-sent signal unifications are handled.
According to the described processing method of claim 1, it is characterized in that 7, this processing method also comprises:
7.1) receiving terminal estimates self channel according to received signal separately;
7.2) detect corresponding described original pre-sent signal in conjunction with unified channel decomposing.
8, according to the described processing method of claim 7, it is characterized in that, described detection is that least mean-square error detects, described step 1.2) comprise that described pseudo channel is carried out unified channel decomposing to be obtained and utilize least mean-square error weight detection matrix that described received signal is detected.
9, a kind of multi-input and multi-output system signal processing unit is characterized in that, comprising:
Transmitting terminal, comprise the modulation module (111.1,111.2), first-time precoding module (112.1,112.2), secondary precoding module (115) and the transmitting antenna array (116) that connect successively, wherein: first-time precoding module (111.1,111.2) is connected with transmitting terminal unified channel decomposing module (113.1,113.2), secondary precoding module (115) is connected with block diagonalization module (116), and block diagonalization processing module (116) output connects transmitting terminal unified channel decomposing module (113.1,113.2);
Receiving terminal, comprise the receiving antenna array (117.1,117.2), detection module (118.1,118.2) and the demodulation module (119.1,119.2) that connect successively, wherein: receiving antenna array (117.1,117.2) is connected with channel estimation module (120.1,120.2), detection module (118.1,118.2) is connected with receiving terminal unified channel decomposing module (121.1,122.2), and channel estimation module (120.1,120.2) output connects receiving terminal unified channel decomposing module (121.1,121.2).
According to the described processing unit of claim 9, it is characterized in that 10, described detection module (118.1,118.2) is least mean-square error detection module or ZF detection module.
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| CN101378282B CN101378282B (en) | 2013-02-27 |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102546088A (en) * | 2010-12-28 | 2012-07-04 | 电子科技大学 | BD (block diagonalization) pre-coding method and device |
| CN104301074A (en) * | 2013-07-15 | 2015-01-21 | 华为技术有限公司 | Interference elimination method and equipment |
| WO2016041196A1 (en) * | 2014-09-19 | 2016-03-24 | 华为技术有限公司 | Multiplexing method for multiple users, base station, and user terminal |
| CN107302388A (en) * | 2017-07-27 | 2017-10-27 | 玉溪师范学院 | A kind of combination treatment method of descending multi-user mimo system |
| CN107688131A (en) * | 2016-08-06 | 2018-02-13 | 国基电子（上海）有限公司 | MIMO antenna system |
| CN109391299A (en) * | 2017-08-10 | 2019-02-26 | 中国电信股份有限公司 | Extensive antenna multiplexing method, transmitting terminal, receiving end and extensive antenna system |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100561890C (en) * | 2005-10-05 | 2009-11-18 | 中兴通讯股份有限公司 | The method and system of down link self adaption in the multiuser mimo system |
| CN1988526B (en) * | 2005-12-23 | 2010-05-05 | 中兴通讯股份有限公司 | Synchronizing method for multiple input multiple output orthogonal frequency division multiplex radio system |
-
2007
- 2007-08-31 CN CN 200710147627 patent/CN101378282B/en not_active Expired - Fee Related
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102546088A (en) * | 2010-12-28 | 2012-07-04 | 电子科技大学 | BD (block diagonalization) pre-coding method and device |
| CN102546088B (en) * | 2010-12-28 | 2016-08-24 | 电子科技大学 | A kind of block diagonalization method for precoding and device |
| CN104301074A (en) * | 2013-07-15 | 2015-01-21 | 华为技术有限公司 | Interference elimination method and equipment |
| CN104301074B (en) * | 2013-07-15 | 2017-11-28 | 华为技术有限公司 | Eliminate the method and apparatus of interference |
| WO2016041196A1 (en) * | 2014-09-19 | 2016-03-24 | 华为技术有限公司 | Multiplexing method for multiple users, base station, and user terminal |
| CN107688131A (en) * | 2016-08-06 | 2018-02-13 | 国基电子（上海）有限公司 | MIMO antenna system |
| CN107302388A (en) * | 2017-07-27 | 2017-10-27 | 玉溪师范学院 | A kind of combination treatment method of descending multi-user mimo system |
| CN109391299A (en) * | 2017-08-10 | 2019-02-26 | 中国电信股份有限公司 | Extensive antenna multiplexing method, transmitting terminal, receiving end and extensive antenna system |
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