CN102769518A - Interference alignment technology based on periodic differential feedback - Google Patents
Interference alignment technology based on periodic differential feedback Download PDFInfo
- Publication number
- CN102769518A CN102769518A CN2012102457050A CN201210245705A CN102769518A CN 102769518 A CN102769518 A CN 102769518A CN 2012102457050 A CN2012102457050 A CN 2012102457050A CN 201210245705 A CN201210245705 A CN 201210245705A CN 102769518 A CN102769518 A CN 102769518A
- Authority
- CN
- China
- Prior art keywords
- cycle
- feedback
- channel information
- channel
- interference
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Landscapes
- Mobile Radio Communication Systems (AREA)
- Detection And Prevention Of Errors In Transmission (AREA)
Abstract
The invention discloses an interference alignment technology based on periodic differential feedback. The interference alignment technology comprises the following steps of: (1) calculating an optimal feedback period; (2) feeding back the differential channel information; (3) reconstructing the channel information; and (4) designing a precoding matrix through the channel information in the nth period by a transmitting end in the (n+1)th period, designing an interference elimination scheme at a receiving end, and separating and eliminating the signal interference at the receiving end. The invention has the beneficial effects that influencing factors of the channel feedback period are considered in a combined mode, and the optimal feedback period is calculated under the condition that uplink feedback channel capacity is given, so that the fed back channel information and a true value have a minimum error; and therefore, the receiving end can separate and eliminate the interference from the signal, the average system capacity is maximized in a period, and the interference elimination capacity and the system performance are optimized.
Description
Technical field
The present invention relates to interference alignment techniques based on the periodicity differential feedback.
Background technology
The restriction that performance in wireless communication systems and capacity usually are interfered is through suppressing or eliminating to disturb and just can improve performance in wireless communication systems.The raising of disturbing alignment techniques to realize resource utilization through the precoding and the receiving terminal interference cancellation scheme of co-design transmitting terminal.Need channel information to come precoding to separate interference space and signal space but a difficulty disturbing alignment techniques to realize is exactly a transmitting terminal, and it can not record itself through.
The differential feedback technology is the important means of Channel Transmission, and promptly transmitting terminal needs channel information, and channel information can record at receiving terminal through methods such as pilot tones, therefore can adopt the method for receiving terminal feedback channel information to address this problem.If consider that in addition channel has temporal correlation; It is the channel information that transmitting terminal needs n time period now; And its known n-1 time period, receiving terminal can only feed back the difference of this two channel information, utilizes this difference and the channel information of n-1 time period to reconstruct the channel information of n time period at transmitting terminal; The method of differential feedback is the compressed feedback bit number further, and makes transmitting terminal have channel information disturbs alignment with design pre-coding matrix.
It is thus clear that; The differential feedback channel information is applied to disturb the problem in the alignment techniques to be, it has supposed that channel can be in the errorless measurement of receiving terminal, and has ignored the expired problem of channel; And these two problems are vital for the pre-coding matrix that the correct channel information of transmitting terminal acquisition aligns with the design interference; Especially channel is expired is serious problems of differential feedback, expired when serious when channel, and interference can't be alignd at receiving terminal; Also just can not eliminate the influence of interference, cause final communication performance to descend.
Summary of the invention
The object of the present invention is to provide a kind of interference alignment techniques based on the periodicity differential feedback; Can make the error minimum of the channel information that obtains of feedback and actual value; Eliminate the influence of disturbing, realize the maximization of average system capacity in the one-period, improve communication performance.
The objective of the invention is to realize through following technical scheme: based on the interference alignment techniques of periodicity differential feedback, it comprises following steps:
(1) compute optimal feedback cycle
Initialization system; Survey channel information, just initial feedback cycle, operational system at receiving terminal; Calculate the expired degree between the adjacent channel in the initial feedback cycle; Measure the error between this adjacent channel simultaneously and quantize this error, the initial feedback cycle of balance calculates the optimum feedback cycle of system to the influence of expired degree and error at receiving terminal;
(2) channel information behind the feedback differential
In n the cycle of optimum feedback cycle; Wherein n is the natural number greater than 1; Receiving terminal is measured earlier this channel information constantly, and through with the channel information difference in n-1 cycle, calculate differential channel information; In the feedback cycle in n cycle, differential channel information is returned feedback of channel information to transmitting terminal through uplink feedback channel, feed back to whole channel informations when promptly n+1 cycle begins to n end cycle;
(3) rebuild channel information
The feedback of transmitting terminal through the n cycle obtains difference information, reconstructs the channel information in n cycle with the n-1 cycle channel information that obtains before;
(4) when n+1 cycle, transmitting terminal is designed pre-coding matrix through the channel information in n cycle, and designs interference cancellation scheme at receiving terminal simultaneously, separates and eliminate the signal interference of receiving terminal.
Under the causality condition, there is the expired problem of channel in system, and along with the increase in cycle, channel is expired more and more serious.Suppose that channel is constant in each time period, and channel has correlation in time, promptly
H wherein
nThe channel of representing n time period, H
N-1The channel of representing n-1 time period, they are the multiple Gaussian distribution with identical variance and average, α is the coefficient correlation of two moment interchannels, W
nIt is the white noise of the variance multiple Gaussian distribution identical with H.When feedback, only need the difference of two time period interchannels of feedback.At this moment; Because causality; The channel information of each time period this time period of feedback; Can only be used to design the pre-coding matrix of transmitting terminal in a back time period, promptly the channel information of n time period could be rebuild at transmitting terminal n+1 time period and obtain, so it can only be used for the design of the pre-coding matrix of n+1 time period.The expired problem of channel that Here it is, and along with each cycle time is elongated, channel relevancy descends, and utilizes the pre-coding matrix of design of last one-period and the interference eliminated of interference cancellation scheme to become not thorough, and the expired problem of channel is serious.Because the channel information correlation during two weeks increases with Cycle Length and reduces, so channel cycle is more little good more.
On the other hand, because the feedback channel capacity is certain, and number of bits of feedback N
f=C
f* T, wherein C
fBe the channel capacity of uplink feedback channel, T is the time span of a time period, i.e. feedback cycle.Along with feedback cycle is elongated, number of bits of feedback increases, and quantizes more accurately, and the quantization error of channel information reduces during feedback, and interference eliminated gets more thorough, thus channel cycle the longer the better.
Through above analysis, the receiving terminal measure error, the problem that can run in the expired many practical applications of quantization error and channel, they can significantly reduce systematic function, and power system capacity is exerted an influence.These influences are responsive for the channel feedback cycle in view of the above; The feedback cycle increase can strengthen quantization error and reduce the expired influence of channel, and there is the problem of a balance in feedback cycle length, and has an optimal value; The present invention is intended to calculate this optimum feedback cycle; Make between channel information that transmitting terminal obtains and actual value error minimum, and with this algorithm application in interference cancellation techniques, optimize interference eliminated ability and systematic function.
The beneficial effect of the inventive method is: through uniting the influencing factor of considering the channel feedback cycle; Under the given situation of uplink feedback channel capacity; Calculate optimum feedback cycle, the channel information that feedback is obtained is minimum with the error of actual value, makes receiving terminal can from signal, isolate interference and with its elimination; Realize the maximization of average system capacity in the one-period, optimized interference eliminated ability and systematic function.
Description of drawings
Fig. 1 is a principle schematic of the present invention.
Embodiment
Further describe technical scheme of the present invention below in conjunction with accompanying drawing, but require the scope of protection to be not limited to said.
Like Fig. 1, based on the interference alignment techniques of periodicity differential feedback, it comprises following steps:
(1) compute optimal feedback cycle
Initialization system; Survey channel information, just initial feedback cycle, operational system at receiving terminal R; Calculate the expired degree between the adjacent channel in the initial feedback cycle; Measure the error between this adjacent channel simultaneously and quantize this error, the initial feedback cycle of balance calculates the optimum feedback cycle of system to the influence of expired degree and error at receiving terminal R;
(2) channel information behind the feedback differential
In n the cycle of optimum feedback cycle; Wherein n is the natural number greater than 1; Receiving terminal R measures earlier this channel information constantly, and through with the channel information difference in n-1 cycle, calculate differential channel information; In the feedback cycle in n cycle, differential channel information is returned feedback of channel information to transmitting terminal through uplink feedback channel, feed back to whole channel informations when promptly n+1 cycle begins to n end cycle;
(3) rebuild channel information
The feedback of transmitting terminal T through the n cycle obtains difference information, reconstructs the channel information in n cycle with the n-1 cycle channel information that obtains before;
(4) when n+1 cycle, transmitting terminal T designs pre-coding matrix through the channel information in n cycle, and designs interference cancellation scheme at receiving terminal R simultaneously, separates and eliminate the signal interference of receiving terminal R.
The present invention is through uniting the consideration measure error in addition; The expired problem of quantization error and channel and the algorithm of the optimization feedback cycle that proposes; Not only can be applicable to disturb alignment techniques, also can be applicable to 3G, 4G etc. are various to be needed at transmitting terminal under the scene of channel information; The differential feedback of optimization feedback cycle can reduce number of bits of feedback and the channel information to be feedback and the error of real channel information to greatest extent, thereby promotes communication system performance.
Claims (1)
1. based on the interference alignment techniques of periodicity differential feedback, be primarily characterized in that: it comprises following steps:
(1) compute optimal feedback cycle
Initialization system; Survey channel information, just initial feedback cycle, operational system at receiving terminal; Calculate the expired degree between the adjacent channel in the initial feedback cycle; Measure the error between this adjacent channel simultaneously and quantize this error, the initial feedback cycle of balance calculates the optimum feedback cycle of system to the influence of expired degree and error at receiving terminal;
(2) channel information behind the feedback differential
In n the cycle of optimum feedback cycle; Wherein n is the natural number greater than 1; Receiving terminal is measured earlier this channel information constantly, and through with the channel information difference in n-1 cycle, calculate differential channel information; In the feedback cycle in n cycle, differential channel information is returned feedback of channel information to transmitting terminal through uplink feedback channel, feed back to whole channel informations when promptly n+1 cycle begins to n end cycle;
(3) rebuild channel information
The feedback of transmitting terminal through the n cycle obtains difference information, reconstructs the channel information in n cycle with the n-1 cycle channel information that obtains before;
(4) when n+1 cycle, transmitting terminal is designed pre-coding matrix through the channel information in n cycle, and designs interference cancellation scheme at receiving terminal simultaneously, separates and eliminate the signal interference of receiving terminal.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210245705.0A CN102769518B (en) | 2012-07-16 | 2012-07-16 | Based on the interference alignment techniques of periodicity differential feedback |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210245705.0A CN102769518B (en) | 2012-07-16 | 2012-07-16 | Based on the interference alignment techniques of periodicity differential feedback |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN102769518A true CN102769518A (en) | 2012-11-07 |
| CN102769518B CN102769518B (en) | 2015-09-02 |
Family
ID=47096780
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201210245705.0A Expired - Fee Related CN102769518B (en) | 2012-07-16 | 2012-07-16 | Based on the interference alignment techniques of periodicity differential feedback |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102769518B (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103476125A (en) * | 2013-09-03 | 2013-12-25 | 郑州大学 | Method and system for optimizing user scheduling in opportunity interference alignment technology |
| CN105744586A (en) * | 2016-03-04 | 2016-07-06 | 上海交通大学 | Full-duplex relay selection method based on outdated channel state information |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101374003A (en) * | 2007-08-23 | 2009-02-25 | 中兴通讯股份有限公司 | Method for transmitting signals of multi-input multi-output system and codebook feedback method |
| CN101378273A (en) * | 2007-08-28 | 2009-03-04 | 中兴通讯股份有限公司 | Method for feedback of channel quality indication with periods |
-
2012
- 2012-07-16 CN CN201210245705.0A patent/CN102769518B/en not_active Expired - Fee Related
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101374003A (en) * | 2007-08-23 | 2009-02-25 | 中兴通讯股份有限公司 | Method for transmitting signals of multi-input multi-output system and codebook feedback method |
| CN101378273A (en) * | 2007-08-28 | 2009-03-04 | 中兴通讯股份有限公司 | Method for feedback of channel quality indication with periods |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103476125A (en) * | 2013-09-03 | 2013-12-25 | 郑州大学 | Method and system for optimizing user scheduling in opportunity interference alignment technology |
| CN103476125B (en) * | 2013-09-03 | 2016-07-13 | 郑州大学 | A kind of chance disturbs optimization method and the system of user scheduling in alignment |
| CN105744586A (en) * | 2016-03-04 | 2016-07-06 | 上海交通大学 | Full-duplex relay selection method based on outdated channel state information |
| CN105744586B (en) * | 2016-03-04 | 2019-10-08 | 上海交通大学 | Full duplex relaying selection method based on expired channel state information |
Also Published As
| Publication number | Publication date |
|---|---|
| CN102769518B (en) | 2015-09-02 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102237955B (en) | Channel state information reporting method and device | |
| WO2010013949A3 (en) | Method for transmitting data in multiple antenna system | |
| MX2019009269A (en) | Multi-beam csi reporting. | |
| WO2012044088A3 (en) | Method and apparatus for efficient feedback in a wireless communication system that supports multiple antennas | |
| CN101689969B (en) | Based on the self-adapting compressing method and apparatus of the channel feedback of second-order channel statistics | |
| US8830932B2 (en) | Obtaining method and device for channel information | |
| KR102189161B1 (en) | Feedback apparatus and method in a multiple-input multiple-output system | |
| EP2757818A3 (en) | Method and system for quantized feedback rate adaptation in a communication system | |
| TWI319665B (en) | Robust rank prediction for a mimo system | |
| WO2013040089A3 (en) | Systems and methods to exploit areas of coherence in wireless systems | |
| BR112015015892A2 (en) | communications method information channel, user equipment, and base station | |
| US20220286257A1 (en) | Method for Wireless Channel Reference Signal Transmission and Channel State Information Feedback | |
| CN101110623B (en) | Part user feedback method for limited feedback of multiple-input multiple-output multi-user system | |
| US20120300654A1 (en) | Adaptive Feedback of Channel Information for Coordinated Transmission on a Wireless Backhaul | |
| CA2586209A1 (en) | Method and device for low bit rate speech coding | |
| US10419094B2 (en) | Channel state information measurement method, channel state information acquisition method, terminal and network device | |
| MX364043B (en) | Parameter update method for entropy coding and decoding of conversion coefficient level, and entropy coding device and entropy decoding device of conversion coefficient level using same. | |
| EP2034682A3 (en) | Beamforming using a codebook in a multiple-user MIMO communication system | |
| EP2795807B1 (en) | Downlink transmission in a mu-mimo system | |
| CA2893295A1 (en) | Multi-tiered quantization of channel state information in multiple antenna systems | |
| US9356668B2 (en) | Method and apparatus for predicting precoding matrix in MIMO system | |
| EP2650966A3 (en) | Optimized uplink performance via antenna selection | |
| WO2009029623A3 (en) | System and method for automated link quality measurement for adaptive modulation systems using noise level estimates | |
| TWI508505B (en) | Transmission method of uplink control information | |
| MY164733A (en) | Method and arrangement in a wireless communication system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20150902 Termination date: 20160716 |