WO2012159266A1 - Procédé de mise en forme de faisceaux à flux multiples auto-adaptative et station de base - Google Patents

Procédé de mise en forme de faisceaux à flux multiples auto-adaptative et station de base Download PDF

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Publication number
WO2012159266A1
WO2012159266A1 PCT/CN2011/074625 CN2011074625W WO2012159266A1 WO 2012159266 A1 WO2012159266 A1 WO 2012159266A1 CN 2011074625 W CN2011074625 W CN 2011074625W WO 2012159266 A1 WO2012159266 A1 WO 2012159266A1
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WO
WIPO (PCT)
Prior art keywords
beamforming
base station
stream
channel
matrix
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Ceased
Application number
PCT/CN2011/074625
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English (en)
Chinese (zh)
Inventor
张翼
周华
吴建明
郭爱煌
于洪林
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Fujitsu Ltd
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Fujitsu Ltd
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Application filed by Fujitsu Ltd filed Critical Fujitsu Ltd
Priority to CN2011800613221A priority Critical patent/CN103270704A/zh
Priority to PCT/CN2011/074625 priority patent/WO2012159266A1/fr
Publication of WO2012159266A1 publication Critical patent/WO2012159266A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B7/00—Radio transmission systems, i.e. using radiation field
    • H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
    • H04B7/04—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas
    • H04B7/06—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station
    • H04B7/0613—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission
    • H04B7/0615—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission of weighted versions of same signal
    • H04B7/0617—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission of weighted versions of same signal for beam forming

Definitions

  • the present invention relates to the field of wireless communications, and in particular, to an adaptive multi-stream beamforming method and a base station for a downlink of a wireless communication system. Background technique
  • LTE-A LTE-Advanced, LTE-based evolution
  • MIMO Multiple-Input Multiple-Out-put
  • LTE-A introduces higher antenna configuration (8Tx DL) and more advanced multi-antenna output modes, such as multi-stream, multi-user, etc.
  • Multi-stream beamforming and multi-user MIMO technology based on this will further improve the system. Capacity and spectrum utilization.
  • the beamforming technology can perform signal preprocessing according to the channel characteristics of the user, and has the ability to expand coverage, increase system capacity, and reduce interference.
  • the receiving end of the MIMO system feeds back the channel state information CSI (Channel State Information) to the transmitting end, and then performs precoding operation on the transmission information, which can greatly improve the performance of the MIMO system.
  • CSI Channel State Information
  • MIMO/SA Smart Antenna
  • PDSCH Physical Downlink Shared Channel
  • a single-user multi-stream beamforming technology can enable a single user to transmit multiple data streams at a certain time, and at the same time obtain a shaping gain and a spatial multiplexing gain, thereby obtaining A larger transmission rate than conventional single-stream beamforming techniques. Therefore, it is important to study single-user multi-stream beamforming techniques.
  • An object of the embodiments of the present invention is to provide an adaptive multi-stream beamforming method and a base station, which extend the existing dual-stream beamforming algorithm to a multi-stream beamforming algorithm, and determine the number of beamforming flows based on the channel capacity. , adaptive transmission of beamforming to improve system flexibility.
  • an adaptive multi-stream beamforming method wherein the method includes:
  • the base station calculates, according to the channel matrix, a channel capacity corresponding to the number of different beamforming flows;
  • the base station selects the number of beamforming streams corresponding to the largest channel capacity for downlink beamforming according to the calculation result of the channel capacity.
  • the beneficial effects of the embodiments of the present invention are: by extending the existing dual-stream beamforming algorithm to the multi-stream beamforming algorithm, and determining the number of beamforming flows based on the channel capacity, thereby realizing adaptive transmission of beamforming, and improving System flexibility.
  • FIG. 1 is a flowchart of an adaptive multi-stream beamforming method according to an embodiment of the present invention
  • the number of beamforming flows can be notified to the UE, so that the UE performs corresponding data transceiving processing according to the number of beamforming flows.
  • the base station can notify the UE of the determined number of beamforming flows, for example, by sending a new message to the UE to indicate the determined number of beamforming flows, or by using the existing message sent to the UE.
  • the reserved field in the field indicates the determined number of beamforming flows, or by other means. The above is only an example, and the embodiment is not limited thereto.
  • the base station may calculate the channel matrix of the downlink according to the uplink and downlink reciprocity of the LTE-A TDD system according to the channel impulse response of the uplink user. For example, the base station determines the channel state information of the uplink according to the Sounding Reference Signal (SRS) reported by the user, and determines the channel state information of the downlink according to the uplink and downlink reciprocity, thereby determining the downlink. Channel matrix.
  • the base station may also determine the channel matrix of the downlink according to other information reported by the user. For example, the user can directly report the channel state information of the downlink to the base station, whereby the base station can also determine the channel matrix of the downlink.
  • SRS Sounding Reference Signal
  • the base station (eNodeB) side employs N antennas
  • the UE (UE) side employs M antennas.
  • M ' may be the same as M or different.
  • Step 201 The base station determines a number of beamforming flows that need to calculate a channel capacity.
  • the number of beamforming flows that need to calculate the channel capacity is single stream and dual stream.
  • the number of beamforming streams that need to calculate channel capacity is single stream, dual stream, third stream, and quad stream. , and so on.
  • H is the channel matrix determined in step 101, ! ! Two ⁇ , ⁇ ...! ! ⁇ is a left singular matrix
  • V [v p > VAi ] is a right singular matrix
  • ⁇ is a diagonal matrix
  • diagonal elements ⁇ , ... ⁇ ? ⁇ is a singular value.
  • the column vector of the right singular matrix is used as the beamforming weight vector.
  • Step 203 The base station calculates, according to the beamforming weight vector and the weighting processing vector of the receiving end, a channel capacity corresponding to each beamforming stream number determined.
  • the base station may first establish a receiving signal model of the receiving end, and calculate a channel capacity corresponding to each determined beamforming stream number based on the received signal model.
  • H is a channel matrix, for example, may be an M x N channel matrix
  • F is a beamforming weight vector
  • X is a transmission signal
  • n is noise.
  • step 203 the base station calculates the channel capacity of each of the beamforming streams determined in step 201, which can be implemented by the method shown in FIG. 3. Referring to FIG. 3, the method includes:
  • Step 301 The base station determines, according to a beamforming weighting vector corresponding to the current beamforming stream number, an equivalent channel matrix corresponding to the current beamforming stream number;
  • the equivalent channel matrix of the channel matrix determined in step 101 is:
  • H can be decomposed into [/ ⁇ V H , and the equivalent channel matrix can be obtained by substituting U, ⁇ and F corresponding to the current beamforming stream into the above equation.
  • Step 302 The base station calculates, according to the equivalent channel matrix, a weighting processing vector of a receiving end of each data stream corresponding to the current beamforming stream number;
  • the weighting processing vector of the receiving end can be expressed as:
  • Step 303 The base station calculates, according to the equivalent channel matrix and the weighting processing vector of the receiving end, and the signal to noise ratio of the receiving end, a signal to interference plus noise ratio (SINR) of each data stream corresponding to the current beamforming stream number.
  • SINR signal to interference plus noise ratio
  • the SINR of one channel of data stream can be calculated; if the dual stream beamforming channel capacity is to be calculated, the SINR of the two channels of data is calculated; if the three stream beamforming channel is to be calculated Capacity, then calculate the SINR of the three-way data stream, and so on.
  • which number of data streams are to be selected to calculate the SINR may be determined according to the diagonal elements in the diagonal matrix after decomposing the channel matrix determined in step 101, according to the order of the diagonal elements from large to small. Select the corresponding data stream.
  • the right singular column vector corresponding to the diagonal element having the largest median value of the diagonal matrix is selected as the beamforming weight vector, and the SINR of the data stream corresponding to the beamforming weight vector is calculated;
  • the SINR of the two data streams two right singular column vectors corresponding to the two diagonal elements of the median of the diagonal array are selected as the beamforming weight vector, and each data corresponding to the beamforming weight vector is calculated.
  • the SINR of the stream and so on.
  • Step 304 The base station calculates, according to the SINR of each data stream corresponding to the current beamforming flow, the channel capacity of the channel corresponding to each data stream.
  • the SINR corresponding to each data stream is obtained, and the channel capacity of the channel corresponding to the data stream can be calculated accordingly.
  • the specific calculation method can be implemented by existing means, and details are not described herein again.
  • Step 305 The base station calculates a total channel capacity corresponding to the current beamforming flow number according to a channel capacity of a channel corresponding to each data stream.
  • the total channel capacity of the current beamforming stream number is obtained by using a channel capacity phase port of a channel of each data stream corresponding to the current beam shaping stream number.
  • the received signal on the user side can be expressed as the product of the weighted processing vector of the receiving end and the received signal.
  • step 203 that is, the method shown in FIG. 3, more clear and easy to understand, the following is a single stream beamforming channel capacity calculation process, a dual stream beamforming channel capacity calculation process, a three-stream beamforming channel capacity calculation process, and four
  • the flow beamforming channel capacity calculation process is taken as an example, and the method of this embodiment is described in detail.
  • the received signal SINR is:
  • the single-stream beamforming channel capacity is:
  • ⁇ 2 is the second largest singular value
  • 1 2 is the second column of the left singular matrix
  • the MMSE detection algorithm is used to eliminate inter-stream interference.
  • the MMSE filter weighting processing vectors at the receiving end are: corpse
  • io 2 (g & H + g 2 g 2 H + ⁇ iy l g of the MMSE receiver signals are:
  • the received SINR is:
  • the channel traversal capacity of the second data stream is:
  • ⁇ 2 is the second largest singular value
  • ⁇ 3 is the third largest singular value
  • ⁇ is the first column of the left singular matrix
  • 2 is the second column of the left singular matrix
  • 3 is The third column of the left singular matrix.
  • x 2 and the MMSE filter weighting vector of the receiving end are:
  • ⁇ 1 ( ⁇ 1 ⁇ 1 ⁇ + ⁇ 2 ⁇ 2 ⁇ + ⁇ 3 ⁇ 3 ⁇ + 3 ⁇ 4 )- 1 ⁇ 1 ;
  • ⁇ 2 (g 1 H +g2 g 2 H +g3 g 3 H + ⁇ iy l g 2 ;
  • ⁇ 3 ⁇ + ⁇ + ⁇ + ⁇ )- ⁇ g 3 So the MMSE receiving signals are:
  • the SINRs received by the second data stream and the third data stream are:
  • the letter corresponding to the different beamforming flows in step 102 can be obtained.
  • the number is subjected to downlink beamforming.
  • the shaping formula can be:
  • ⁇ (0 represents the transmitted signal of antenna port p
  • v sacrifice is the nth right singular vector, which is the data after beamforming.
  • An embodiment of the present invention provides an adaptive multi-stream beamforming method applied in a TDD LTE-Advanced system.
  • the method uses channel capacity as a decision mechanism, considers channel conditions, and adaptively selects a beamforming stream number, and increases The flexibility of the system increases the overall performance of the TDD LTE-Advanced system.
  • An embodiment of the present invention further provides a base station, as described in Embodiment 2 below.
  • a base station refer to the implementation of the method in Embodiment 1, and the description of the method is not repeated here.
  • FIG. 4 is a schematic structural diagram of a base station according to an embodiment of the present invention.
  • the base station includes: a determining unit 41, configured to determine a channel matrix of the downlink according to information sent by the UE; and a calculating unit 42 that calculates different beams according to the channel matrix determined by the determining unit 41.
  • the channel capacity corresponding to the number of shaped streams;
  • the selecting unit 43 performs downlink beamforming according to the calculation result of the channel capacity by the calculating unit 42 and selecting the number of beamforming streams corresponding to the channel capacity.
  • the base station further includes:
  • the notifying unit 44 is configured to notify the user of the number of beamforming flows selected by the selecting unit 43.
  • the calculating unit 42 includes:
  • a determining module 421, configured to determine a number of beamforming flows that need to calculate a channel capacity
  • the decomposition module 422 is configured to decompose the channel matrix determined by the determining unit 41 by using a singular value decomposition SVD decomposition method, and use the column vector of the decomposed right singular matrix as a beamforming weight vector;
  • the determining module 421 includes:
  • a comparison sub-module 4211 configured to compare the number of antennas on the base station side with the number of antennas on the user side; and determine a sub-module 4212, configured to compare the number of antennas according to the comparison result of the comparison sub-module 4211 The smaller one is the maximum number of beamforming flows that need to calculate the channel capacity, and the number of beamforming flows that need to calculate the channel capacity is determined to be a single stream to the maximum beamforming stream number.
  • the decomposition module 422 is specifically configured to decompose the channel matrix determined by the determining unit according to the following formula:
  • H is the channel matrix
  • U is the left singular matrix
  • V is the right singular matrix
  • ⁇ is the diagonal matrix
  • the calculating module 423 is specifically configured to: determine, according to a beamforming weighting vector corresponding to the current beamforming stream number, an equivalent channel matrix corresponding to the current beamforming stream number; according to the equivalent channel a matrix, calculating a weighting processing vector of a receiving end of each data stream corresponding to the current beamforming stream number; calculating a corresponding current beam assignment according to the equivalent channel matrix and the weighting processing vector of the receiving end, and the signal to noise ratio of the receiving end a signal-to-interference plus noise ratio SINR of each data stream of the number of streams; calculating a channel capacity of a channel corresponding to each of the data streams according to the SINR of each data stream corresponding to the current beamforming stream; Corresponding to the channel capacity of the channel of each of the data streams, the total channel capacity corresponding to the current beamforming stream number is calculated.
  • the calculation module 423 is specifically configured to calculate a weighting processing vector of the receiving end of each data stream corresponding to the current beamforming stream according to the following formula:
  • An embodiment of the present invention provides a base station used in a TDD LTE-Advanced system, where the base station adopts an adaptive multi-stream beamforming method, and uses channel capacity as a decision mechanism to consider channel conditions and adaptively select beamforming flows. Increases the flexibility of the system, which in turn improves the overall performance of the TDD LTE-Advanced system.
  • Embodiments of the present invention also provide a computer readable program, wherein when the program is executed in a base station, the program causes a computer to perform the adaptive multi-stream beamforming method of Embodiment 1 in the base station.
  • An embodiment of the present invention further provides a storage medium storing a computer readable program, wherein the computer The reading program causes the computer to perform the adaptive multi-stream beamforming method described in Embodiment 1 in the base station.
  • the above apparatus and method of the present invention may be implemented by hardware, or may be implemented by hardware in combination with software.
  • the present invention relates to a computer readable program that, when executed by a logic component, enables the logic component to implement the apparatus or components described above, or to cause the logic component to implement the various methods described above Or steps.
  • Logic components such as field programmable logic components, microprocessors, processors used in computers, and the like.
  • the present invention also relates to a storage medium for storing the above program, such as a hard disk, a magnetic disk, an optical disk, a DVD, a flash memory, or the like.

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  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Mobile Radio Communication Systems (AREA)
  • Radio Transmission System (AREA)

Abstract

Les modes de réalisation de la présente invention décrivent un procédé de mise en forme de faisceaux à flux multiples auto-adaptative et une station de base. Ledit procédé se déroule de la manière suivante : la station de base définit une matrice de canal d'une liaison descendante en fonction des informations transmises par un terminal utilisateur (101); la station de base calcule les capacités de canal correspondant à des nombres différents de flux de mise en forme de faisceaux en fonction de la matrice de canal (102); et, selon les résultats de calcul de la capacité de canal, ladite station de base sélectionne le nombre de flux de mise en forme de faisceaux correspondant à la capacité de canal maximale afin de réaliser une mise en forme de faisceaux en liaison descendante (103). Le procédé et la station de base décrits dans les modes de réalisation de la présente invention font d'un algorithme de mise en forme de faisceaux à deux flux qui était utilisé précédemment un algorithme de mise en forme de faisceaux à flux multiples et déterminent le nombre de flux de mise en forme de faisceaux en fonction des capacités de canal, ce qui permet une transmission auto-adaptative de la mise en forme de faisceaux et une amélioration de la souplesse du système.
PCT/CN2011/074625 2011-05-25 2011-05-25 Procédé de mise en forme de faisceaux à flux multiples auto-adaptative et station de base Ceased WO2012159266A1 (fr)

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Application Number Priority Date Filing Date Title
CN2011800613221A CN103270704A (zh) 2011-05-25 2011-05-25 自适应多流波束赋形方法和基站
PCT/CN2011/074625 WO2012159266A1 (fr) 2011-05-25 2011-05-25 Procédé de mise en forme de faisceaux à flux multiples auto-adaptative et station de base

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CN118074772A (zh) * 2024-04-25 2024-05-24 商飞智能技术有限公司 面向多终端设备的波束赋形方法、装置、基站和存储介质

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CN115065386B (zh) * 2022-06-10 2023-11-17 杭州红岭通信息科技有限公司 基于zf和svd混合预编码的波束赋形优化方法及装置
CN115102591B (zh) * 2022-08-25 2023-01-20 北京智芯微电子科技有限公司 基于反注水的波束赋形方法、装置、设备及可读存储介质

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WO2020001259A1 (fr) * 2018-06-26 2020-01-02 华为技术有限公司 Procédé de traitement de signal, unité en bande de base et unité radio distante
CN118074772A (zh) * 2024-04-25 2024-05-24 商飞智能技术有限公司 面向多终端设备的波束赋形方法、装置、基站和存储介质

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