WO2010081412A1

WO2010081412A1 - Method, system, user equipment and base station for pre-coding feedback

Info

Publication number: WO2010081412A1
Application number: PCT/CN2010/070146
Authority: WO
Inventors: 王晓东; 李斌; 沈晖; 罗毅; 刘锋
Original assignee: 华为技术有限公司
Priority date: 2009-01-15
Filing date: 2010-01-13
Publication date: 2010-07-22
Also published as: CN101783776B; CN101783776A; JP5424222B2; JP2012515478A

Abstract

A method, system, user equipment and base station for pre-coding feedback are provided. The method includes the following steps: receiving random beam information flows; determining the optimal beam set according to the signal to interference-plus-noise ratio (SINR) of the random beam information flows; getting the feedback threshold value; feeding back the information of at least one beam, of which the SINR is larger than the feedback threshold value, in the optimal beam set. The method can decrease the pre-coding feedback quantity.

Description

Precoding feedback method and system, user equipment and base station

This application claims priority to Chinese Patent Application No. 200910076683.8, entitled "Pre-coded Feedback Method and System, User Equipment and Base Station" on January 15, 2009, the entire contents of which are incorporated by reference. In this application. Technical field

The present invention relates to mobile communication technologies, and in particular, to a precoding feedback method and system, a user equipment, and a base station. Background technique

Multiple Input Multiple Output (MIMO) technology can greatly improve the transmission rate of wireless communication systems without increasing the bandwidth, and meet the requirements of high-speed data transmission services. In a MIMO system, the use of precoding techniques to simultaneously transmit multiple data streams can improve the reliability and transmission rate of the transmission link. The precoding technique is based on the assumption that the transmitting end knows all or part of the channel state information. Therefore, in many cases, the receiving end needs to feed back the channel state information to the transmitting end. In a multi-user environment, random beamforming is a possible solution to reduce the amount of feedback. In a multi-user environment, random scheduling can make full use of multi-user diversity to improve system throughput. Usually, the more users, the greater the throughput, and the functional relationship between system throughput and number of users when the number of users tends to infinity. For the optimal and capacity expansion law, the optimal and capacity expansion law is A^loglog, where ^ is the number of transmitting antennas on the base station side, which is the number of users. Both Zero Forcing (ZF) and Opportunistic Orthogonal Random Beamforming (ORB) in the random beamforming scheme can achieve optimal and capacity expansion laws.

The inventors have found that the prior art has at least the following problems: In the prior art, if the optimal and capacity expansion laws need to be achieved, the feedback overhead of the user to the base station is large. Summary of the invention

The invention provides a precoding feedback method and system, a user equipment and a base station, which solve the problem of large feedback overhead.

An embodiment of the present invention provides a precoding feedback method, including:

Receiving a random beam information stream, and determining an optimal beam set according to a signal to interference and noise ratio of the random beam information stream;

Obtain a feedback threshold;

The feedback optimal beam sets information of at least one beam having a signal to interference and noise ratio higher than the feedback threshold.

The embodiment of the invention provides a user equipment, including:

a receiving module, configured to receive a random beam information stream, and determine an optimal beam set according to a signal to interference and noise ratio of the random beam information stream;

An obtaining module, configured to obtain a feedback threshold;

The feedback module is connected to the receiving module and the acquiring module, and is configured to feed back information of at least one beam whose signal to interference and noise ratio is higher than the feedback threshold.

An embodiment of the present invention provides a base station, including:

a calculation module, configured to determine, according to at least one of a signal to interference and noise ratio distribution function, a total number of user equipments, and an environmental factor corresponding to each user equipment, a feedback threshold value for each user equipment; or a user according to a signal to interference and noise ratio distribution function, a user At least one of the total number of devices and the environmental factors corresponding to each user equipment obtains a feedback threshold for each user equipment; and obtains a common feedback threshold according to a predetermined policy and a feedback threshold for each user equipment;

The sending module is connected to the computing module, and is configured to send the feedback threshold of each user equipment or the common feedback threshold to the user equipment.

An embodiment of the present invention provides a precoding feedback system, including:

a base station, configured to send a random beam information flow and threshold information to the user equipment;

a user equipment, connected to the base station, configured to acquire an optimal beam according to the random beam information And collecting, according to the threshold information, a feedback threshold, and feeding back information of at least one beam whose signal to interference and noise ratio is higher than a feedback threshold in the optimal beam set.

It can be seen from the above technical solution that the threshold of the present invention can reduce the feedback overhead in the random beamforming scheme by setting the threshold value and feeding back the corresponding information when the signal to interference and noise ratio of the optimal beam exceeds the threshold. DRAWINGS

1 is a schematic flow chart of a method according to a first embodiment of the present invention;

2 is a schematic structural view of a first embodiment of the present invention;

3 is a schematic flow chart of Embodiment 1 of a method for obtaining a feedback threshold in the first embodiment of the present invention;

4 is a schematic flow chart of Embodiment 2 of a method for obtaining a feedback threshold in the first embodiment of the present invention;

FIG. 5 is a schematic flow chart of Embodiment 3 of a method for obtaining a feedback threshold in the first embodiment of the present invention;

6 is a simulation relationship diagram of the total number of users and the capacity in the first embodiment of the present invention; FIG. 7 is a graph showing the relationship between the signal-to-noise ratio and the capacity in the first embodiment of the present invention; FIG. 9 is a schematic structural diagram of a user equipment according to a second embodiment of the present invention; FIG.

FIG. 10 is a schematic structural diagram of a base station according to a third embodiment of the present invention; FIG.

FIG. 11 is a schematic structural diagram of a precoding feedback system according to a fourth embodiment of the present invention. detailed description

The technical solution of the present invention will be further described in detail below through the accompanying drawings and embodiments. 1 is a schematic flow chart of a method according to a first embodiment of the present invention, and FIG. 2 is a schematic structural diagram of a first embodiment of the present invention. Referring to FIG. 1, an embodiment of the present invention includes: Step 11: The user equipment receives the random beam information stream, and determines an optimal beam set according to the signal to interference and noise ratio of the random beam information stream.

Step 12: The user equipment obtains the feedback threshold.

Steps 11, 12 have no timing constraints.

Step 13: The user equipment feeds back, to the base station, information about at least one beam whose signal to interference and noise ratio is higher than the feedback threshold in the optimal beam set.

In this embodiment, the feedback threshold is obtained, and the feedback overhead is reduced when the signal to interference and noise ratio of the optimal beam of the user equipment is higher than the feedback threshold.

The steps are described in more detail below:

About step 11:

For example, in the following multi-user MIMO system, the base station has N, the root transmitting antenna, and there are a total of user equipments in the system, and each user equipment is equipped with N receiving antennas.

As shown in FIG. 2, if a random orthogonal beamforming scheme is adopted, the base station is distributed according to isotropic

At time t, the first information stream x _m (t) is multiplied by φ _Μ (ί) , and N, accumulate to obtain the transmitted signal "^) = ∑ ^ ^ ^ ^), assuming that the transmitter satisfies the average power constraint

Suppose the information flow is statistically independent, and assume that the average transmit power of the daily lines is equal: E[|x _m (t)| ² ] = , let _P = be the transmit SNR per stream. The Gaussian white noise of each user equipment is represented by ^G C ^xl , z _k ~ C 0, I _N ), and the received signal vector of each user equipment is

, Κ For the case where different user equipments experience different path loss and shadow fading, the channel block H _k is independent, and H _t e CN(0, 1).

The signal-to-interference ratio 8^ „ ₁ of the mth information stream received by the first user equipment is expressed as follows: SINR _t , K, w-Ι, Λ , N _t

Wherein, when the number of receiving antennas is one, the optimal beam set is composed of a beam with the largest signal to interference and noise ratio; when the number of receiving antennas of the user equipment is greater than one, the signal is dry and noise according to the signal to interference and noise ratio from large to small. The relatively large N beams constitute an optimal beam set, where N≤Nr, Nr is the number of receiving antennas of each user equipment. The following is an example of selecting an optimal beam, that is, the optimal beam of the Ath user equipment is calculated as: m = arg max SINR _km .

^K l≤m≤N, '

About step 12:

The feedback threshold is determined according to one or more of a signal to interference and noise ratio distribution function, a total number of user equipments, and environmental factors corresponding to each user equipment, or further determined according to a predetermined policy. For the method of obtaining the threshold value, refer to the embodiment shown in Figure 3-5.

FIG. 3 is a schematic flowchart of Embodiment 1 of a method for obtaining a feedback threshold in the first embodiment of the present invention. In this embodiment, a base station generates a threshold value corresponding to each user equipment for each user equipment. Referring to FIG. 3, this embodiment includes:

Step 301: The base station obtains a feedback threshold O _t for each user equipment according to the total number of user equipments and different environmental factors of each user equipment (for example, path loss and shadow) and a signal to interference and noise ratio distribution function. .

The principle that the base station determines the threshold p( _k ,f) according to the total number of user equipments K and y _{k is} as follows:

ΡΜ , κ)) = ι-^, where (Α^, )) is the cumulative distribution function of w, in the above-mentioned false

Under the condition, the cumulative distribution function of ^ is: ^{F x} ) ^{= 1} _( _{x + 1)} w “i . According to the calculation formula of the feedback threshold value, the design is different for user equipments with different path loss and shadow. Feedback thresholds can improve fairness, such as user equipment with more shadows and path loss, and feedback thresholds should be allocated lower, which can improve the fairness of the system. The formula is determined according to the total number of user equipments, environmental factors, and the signal-to-noise ratio distribution function. In practical applications, the calculation formulas may be different, for example, only related to one or more of the above parameters.

Step 302: The base station sends the feedback threshold to the corresponding user equipment, and each user equipment obtains the feedback threshold for itself.

In this embodiment, the feedback threshold value for each user equipment is calculated by the base station, and an appropriate threshold value may be determined according to different conditions of each user equipment.

FIG. 4 is a schematic flowchart of Embodiment 2 of a method for obtaining a feedback threshold in the first embodiment of the present invention. In this embodiment, a base station generates a common feedback threshold for each user equipment. Referring to Figure 4, this embodiment includes:

Step 401: The same as step 301 of the third embodiment, and details are not described herein again.

Step 402: The base station processes the feedback threshold for each user equipment according to a preset policy to obtain a common feedback threshold. For example, the feedback thresholds are averaged to obtain an average value.

Step 403: The base station sends a common feedback threshold to each user equipment, and each user equipment obtains the common feedback threshold.

In this embodiment, the base station calculates the same feedback threshold for each user equipment, so that each user equipment can obtain an appropriate common threshold.

FIG. 5 is a schematic flowchart of Embodiment 3 of a method for obtaining a feedback threshold in the first embodiment of the present invention. In this embodiment, each user equipment pin generates a feedback threshold corresponding to itself. Referring to Figure 5, this embodiment includes:

Step 501: The base station sends the total number of user equipments K and different environmental factors of each user equipment to each corresponding user equipment.

Step 502: Each user equipment obtains its own feedback threshold according to the foregoing information sent by the base station and the signal to interference and noise ratio distribution function. That is, each user equipment determines the threshold according to the total number of user equipments and ^

The principle of Α^, ) is as follows: F _k 3(j _k , Ky) = —^^ , where F y _k , K SINR _k , _m cumulative distribution function, under the above assumptions, the cumulative distribution function of sn t for: e PYk In this embodiment, the user equipment calculates its own feedback threshold, which can reduce the burden on the base station. About step 13:

For example, when the number of receiving antennas is one, when the signal to noise ratio of the optimal beam is higher than the feedback threshold, the information of the optimal beam is fed back (for example, the beam number); when the number of receiving antennas of the user equipment is greater than 1 Comparing the signal-to-noise ratio and the feedback threshold of the beam in the optimal beam set composed of the N beams, and feeding back the information of the beam in the N beams with the signal-to-noise ratio higher than the feedback threshold, where

Ν ≤ Ν _Γ , the number of receiving antennas for each user.

In particular, each user equipment k comparator 57M? _T, and the threshold, such as _{SINR t,> β (γ,} , Κ), user equipment feedback the most appropriate beam (which requires log N, bits), otherwise the user The device does not feed back any information.

Then, corresponding to each beam, the user set S _m of all the beam numbers that are received by the base station is: B _m = {km = Mg max SINR _{kl and} SINR _km > (y _k , K), k = Ι, Λ, K}. After obtaining the set of users, the base station may further randomly select a user equipment from each user set, and schedule the user equipment to receive the information stream x _m corresponding to the beam. Since they are mutually disjoint, this ensures that one user equipment is not allocated more than one beam.

After adopting the above threshold-based feedback method, the feedback amount can be reduced on the basis of obtaining the optimal and capacity expansion laws. The effect is illustrated below in a simulation diagram.

6 is a simulation relationship diagram of the total number of users and the capacity in the first embodiment of the present invention. The simulation basis of this embodiment is that the number of transmitting antennas is 4, and the number of receiving antennas of each user equipment is 1, the signal to noise ratio p It is 10dB. The Dirty-Paper Coding (DPC) method is the optimal precoding method. The other precoding methods are the optimal optimal zero-pre-coding method (Optim ZF) and the opportunity orthogonality. Precoding method (Opportunistic ORB), 1-bit feedback pre- A coding method (1-Bit Feedback), and a 1-Bit ORB method based on an embodiment of the present invention. It can be seen from FIG. 6 that when the total number of user equipments tends to infinity, the trend of the curves tends to be uniform, that is, the pre-coding method based on the present embodiment can achieve an optimal and capacity expansion law. It can be seen from FIG. 6 that when the total number of user equipments is small, the precoding method and the optimal precoding curve according to the embodiment of the present invention are also similar, that is, when the total number of user equipments is small, based on the embodiment of the present invention. The precoding method can also have some better performance.

7 is a simulation relationship diagram of signal-to-noise ratio and sum capacity in the first embodiment of the present invention. The simulation basis of this embodiment is that the number of transmitting antennas is 4, and the number of receiving antennas N of each user equipment is 1, user equipment. The total is 100. It can be seen from Fig. 7 that the trend of each curve is also that the optimum and capacity law can be achieved in this embodiment when the signal-to-noise ratio changes.

FIG. 8 is a graph showing a simulation relationship between the total number of users and the feedback amount in the first embodiment of the present invention. The curve from top to bottom shows the relationship between the total number of user equipments and the feedback amount when the number of transmitting antennas is 6, 5, 4, and 3 respectively. As can be seen from Figure 8, the total number of user equipments tends to be different. The limit values at infinity are 61og6, 51og5, 41og4, 31og3, respectively, that is, the average feedback rate of this embodiment will be N _t \o _g N _t . However, the threshold-based feedback mechanism is not used in the prior art, and for each user, there is a maximum of min A^NJlogN, bit feedback, and the feedback bits of the entire system may reach

Bit, so its feedback overhead is too large. After adopting this scheme, the average total feedback overhead is A^logN, bit. Compared with the feedback amount of the existing 1^^, ^)1 0 _§ , the feedback amount can be greatly reduced.

FIG. 9 is a schematic structural diagram of a user equipment according to a second embodiment of the present invention, including a receiving module 91, an obtaining module 92, and a feedback module 93. The receiving module 91 is configured to receive a random beam information stream, and determine an optimal beam set according to a signal to interference and noise ratio of each random beam information stream; the obtaining module 92 is configured to obtain a feedback threshold value; and the feedback module 93 is configured to feedback the receiving module 91. The optimal beam sets information of at least one beam whose signal to interference and noise ratio is higher than the feedback threshold obtained by the obtaining module 92.

The obtaining module 92 is specifically configured to receive a feedback threshold corresponding to the user equipment sent by the base station, and the feedback threshold corresponding to the user equipment is used by the base station according to a signal to interference and noise ratio distribution function, and the total user equipment. And determining at least one of an environmental factor corresponding to the user equipment; or, acquiring a module

The specific feedback threshold value is the same for each user equipment sent by the base station, and the common feedback threshold value for each user equipment is determined by the base station according to the signal to interference and noise ratio distribution function, the total number of user equipments, At least one of the environmental factors corresponding to the user equipment and the predetermined policy is determined; or the acquiring module 92 is specifically configured to receive the total number of user equipments and environmental factors sent by the base station, and the user equipment according to the signal to interference and noise ratio distribution function and the user equipment One of the total and environmental factors determines the feedback threshold.

In this embodiment, by acquiring the threshold value, when the signal to interference and noise ratio of the optimal beam is higher than the threshold value, the information of the optimal beam is fed back, and the feedback amount can be reduced.

FIG. 10 is a schematic structural diagram of a base station according to a third embodiment of the present invention, which includes a calculation module 101 and a sending module 102. The calculation module 101 is configured to calculate a feedback threshold. The sending module 102 is configured to send the feedback threshold obtained by the calculation module 101 to the user equipment, where the user equipment has at least one signal to interference and noise ratio higher than the feedback threshold. The information of the beam of values is fed back to the base station.

The calculation module 101 is specifically configured to determine a feedback threshold value for each user equipment according to at least one of a signal to interference and noise ratio distribution function, a total number of user equipments, and an environmental factor corresponding to each user equipment; or, the calculation module 101 is specifically used. Obtaining a feedback threshold value for each user equipment according to at least one of a signal to interference and noise ratio distribution function, a total number of user equipments, and an environmental factor corresponding to each user equipment; and according to a predetermined policy and a feedback threshold value for each user equipment Get a common feedback threshold.

Further, the embodiment may further include a selection module, configured to receive beam information sent by each user equipment, to form a user set for each beam, and randomly select a user equipment in the user set corresponding to the same beam information, and the beam is selected. The data is sent to a randomly selected user device.

In this embodiment, the feedback threshold is obtained by the calculation, and the feedback threshold is sent to the user equipment, so that the user equipment feedbacks when the signal to interference and noise ratio of the optimal beam is higher than the threshold, and the feedback amount can be reduced.

FIG. 11 is a schematic structural diagram of a precoding feedback system according to a fourth embodiment of the present invention, including a base station 111 and a user equipment 112. The base station 111 is configured to send the beam information stream and the threshold information; the user equipment The algorithm is configured to obtain an optimal beam set according to the random beam information sent by the base station 111, obtain a feedback threshold according to the threshold information sent by the base station 111, and feed back at least one signal to interference and noise ratio in the optimal beam set is higher than a feedback threshold. The value of the beam information.

The threshold information may be specifically a feedback threshold corresponding to each user equipment, and the base station 111 is specifically configured to determine, according to at least one of a signal to interference and noise ratio distribution function, a total number of user equipments, and an environmental factor corresponding to each user equipment, The feedback threshold is used by the user equipment 112 to receive the feedback threshold corresponding to the base station 111.

Alternatively, the threshold information may be specifically a feedback threshold value common to each user equipment, and the base station 111 is specifically configured to determine, according to at least one of a signal to interference and noise ratio distribution function, a total number of user equipments, and an environmental factor corresponding to each user equipment, for each user. a feedback threshold of the device, and a common feedback threshold is obtained according to a predetermined policy and a feedback threshold for each user equipment. The user equipment 112 is specifically configured to receive the common publicity of each user equipment obtained by the base station 111. Feedback threshold.

Or the base station 111 is specifically configured to send the total number of user equipments and the environmental factors corresponding to the user equipments to the corresponding user equipments; the user equipment 112 according to the signal to interference and noise ratio distribution function, the total number of user equipments, and environmental factors sent by the base station 111 At least one of the determinations determines a respective feedback threshold.

Further, the base station 111 is further configured to receive the beam information sent by each user equipment, and form a user set for each beam; and randomly select a user equipment in the user set corresponding to the same beam information, and send the data of the beam to the random Selected user device.

In this embodiment, the feedback threshold is obtained in different manners. When the signal to interference and noise ratio of the optimal beam is higher than the feedback threshold, the feedback of the optimal beam information can reduce the feedback amount.

A person skilled in the art can understand that all or part of the steps of implementing the above method embodiments may be completed by using hardware related to program instructions, and the foregoing program may be stored in a computer readable storage medium, and the program is executed when executed. The foregoing steps include the steps of the foregoing method embodiments; and the foregoing storage medium includes: a medium that can store program codes, such as a ROM, a RAM, a magnetic disk, or an optical disk.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention, rather than The present invention has been described in detail with reference to the preferred embodiments. It will be understood by those skilled in the art that the invention may still be modified or substituted, and the modifications or equivalents may not be modified. The latter technical solution departs from the "God and scope" of the technical solution of the present invention.

Claims

Rights request

A precoding feedback method, comprising:

Receiving a random beam information stream, and determining an optimal wave acquisition feedback threshold according to a signal to interference and noise ratio of the random beam information stream;

Feeding at least one letter of the beam with a signal to interference and noise ratio higher than the feedback threshold in the optimal beam set

The method according to claim 1, wherein the obtaining the feedback threshold comprises: receiving a feedback threshold corresponding to each user equipment sent by the base station, and the feedback corresponding to each user equipment The threshold value is determined by the base station according to at least one of a signal to interference and noise ratio distribution function, a total number of user equipments, and an environmental factor corresponding to each user equipment; or

And receiving, by the base station, a common feedback threshold that is the same for each user equipment, where the common feedback threshold is determined by the base station according to a signal to interference and noise ratio distribution function, a total number of user equipments, and environmental factors corresponding to each user equipment. a parameter and a predetermined policy determination; or,

The user equipment receives the total number of user equipments and environmental factors, and the user equipment determines the feedback threshold according to at least one of a signal to interference and noise ratio distribution function and the total number of user equipments and environmental factors.

The method according to claim 2, wherein the calculation formula for determining the feedback threshold according to at least one of a signal to interference and noise ratio distribution function, a total number of user equipments, and an environmental factor is:

Where is (the feedback threshold of the kth user equipment, K is the total number of user equipments, and is the number of receiving antennas of the user equipment; e PYk

The expression of the function F _k is: ^( ) ^{= 1} - _{( + 1)} ^-ΐ , where N _t is the number of transmitting antennas of the base station, p is the signal-to-noise ratio of each transmitting antenna, and ^ is the kth User equipment corresponding ring Circumstances.

The method according to claim 2, wherein the determining a common feedback threshold according to a signal to interference and noise ratio distribution function, a total number of user equipments, at least one of environmental factors corresponding to each user equipment, and a predetermined policy Values include:

And obtaining a feedback threshold value for each user equipment according to at least one of a signal to interference and noise ratio distribution function, a total number of user equipments, and an environmental factor corresponding to each user equipment;

A common feedback threshold is obtained according to a predetermined policy and a feedback threshold for each user equipment.

The method according to claim 1, wherein the determining the optimal beam set according to the signal to interference and noise ratio of the random beam information stream comprises: when the number of receiving antennas of the user equipment is one, The beam with the largest signal-to-noise ratio constitutes the optimal beam set. When the number of receiving antennas of the user equipment is greater than one, the N beams with relatively large dry-noise signals form an optimal beam set, where N≤Nr , Ν _Γ The number of receiving antennas for each user.

6. A user equipment, comprising:

An obtaining module, configured to obtain a feedback threshold;

7. The user equipment according to claim 6, wherein:

The acquiring module is specifically configured to receive a feedback threshold corresponding to the user equipment sent by the base station, where the feedback threshold corresponding to the user equipment is determined by the base station according to a signal to interference and noise ratio distribution function, a total number of user equipments, and At least one of the environmental factors corresponding to the user equipment is determined; or the acquiring module is specifically configured to receive a common feedback threshold that is sent by the base station and is the same for each user equipment, where the common feedback threshold is Determined by the base station according to at least one of a signal to interference and noise ratio distribution function, a total number of user equipments, and environmental factors corresponding to each user equipment; and a predetermined policy; or The acquiring module is specifically configured to receive a total number of user equipments and environmental factors sent by the base station, where the user equipment determines a feedback threshold according to at least one of a signal to interference and noise ratio distribution function and the total number of user equipments and environmental factors.

8. A base station, comprising:

a calculation module, configured to determine, according to at least one of a signal to interference and noise ratio distribution function, a total number of user equipments, and an environmental factor corresponding to each user equipment, a feedback threshold value for each user equipment; or a user according to a signal to interference and noise ratio distribution function, a user At least one of the total number of devices and the environmental factors corresponding to each user equipment obtains a feedback threshold for each user equipment, and obtains a common feedback threshold according to a predetermined policy and a feedback threshold for each user equipment;

The method according to claim 8, wherein the calculating module determines the calculation of the feedback threshold value for each user equipment according to at least one of a signal to interference and noise ratio distribution function, a total number of user equipments, and an environmental factor. The formula is:

Where is (the feedback threshold of the kth user equipment, K is the total number of user equipments, and is the number of receiving antennas of the user equipment; e P

The expression of the function F _k is: ^ ^{( ) = 1} ~ ( _{+ 1} ) ^ -1 , where N _t is the number of transmitting antennas of the base station, p is the signal-to-noise ratio of each transmitting antenna, and ^ is the kth The environmental factor corresponding to the user equipment.

The base station according to claim 8, further comprising:

a selection module, configured to receive beam information sent by each user equipment, to form a user set for each beam; and randomly select a user equipment in a user set corresponding to the same beam information, and send the data of the beam to the randomly selected user equipment .

11. A precoding feedback system, comprising:

The user equipment is connected to the base station, configured to obtain an optimal beam set according to the random beam information, obtain a feedback threshold according to the threshold information, and feed back at least one signal to interference and noise ratio in the optimal beam set is higher than a feedback threshold. The value of the beam information.

12. The system of claim 11 wherein:

The threshold information sent by the base station is specifically a feedback threshold for each user, and the base station is specifically configured to determine, according to at least one of a signal to interference and noise ratio distribution function, a total number of user equipments, and an environmental factor corresponding to each user equipment. Feedback threshold of each user equipment;

The user equipment is specifically configured to receive a feedback threshold that is obtained by the base station and corresponds to itself.

13. The system of claim 11 wherein:

The threshold information sent by the base station is specifically a common feedback threshold, and the base station is specifically configured to determine, according to at least one parameter of a signal to interference and noise ratio distribution function, a total number of user equipments, and environmental factors corresponding to each user equipment, a feedback threshold of the device, and obtaining a common feedback threshold according to a predetermined policy and a feedback threshold for each user equipment;

The user equipment is specifically configured to receive the common feedback threshold.

14. The system of claim 11 wherein:

The threshold information sent by the base station is specifically the total number of the user equipments and the environmental factors corresponding to the user equipments, and the base station is specifically configured to send the total number of the user equipments and the environmental factors corresponding to the user equipments to the corresponding user equipments;

The user equipment determines a respective feedback threshold according to at least one of a signal to interference and noise ratio distribution function, a total number of user equipments, and an environmental factor sent by the base station.

15. The system of claim 11 wherein:

The base station is further configured to receive beam information sent by each user equipment, form a user set for each beam, and randomly select a user equipment in a user set corresponding to the same beam information, and send the data of the beam to the randomly selected user. device.