WO2015078001A1

WO2015078001A1 - Precoding vector determination method, precoding processing method and base station

Info

Publication number: WO2015078001A1
Application number: PCT/CN2013/088211
Authority: WO
Inventors: 王磊; 吴晔; 乔德礼
Original assignee: 华为技术有限公司
Priority date: 2013-11-29
Filing date: 2013-11-29
Publication date: 2015-06-04
Also published as: CN105359428B; CN105359428A

Abstract

Provided are a precoding vector determination method, a precoding processing method and a base station. The base station comprises a plurality of transmitting antennas; an antenna failure detection module used for sending an antenna failure notification to a precoding vector determination device when monitoring that a transmitting antenna fails, the antenna failure notification comprising the serial number of the transmitting antenna which has failed; the precoding vector determination device used for updating a precoding vector according to the serial number of the transmitting antenna which has failed when receiving the antenna failure notification; and a precoding processing module used for conducting precoding processing on a transmitting signal according to the updated precoding vector so as to enable a transmitting signal to have a beam shape of a wide beam. By means of the precoding vector determination method, the precoding processing method and the base station provided in the embodiments of the present invention, a wide beam signal can still be maintained when a transmitting antenna fails, thereby eliminating the influence of an antenna failure on the wide beam signal.

Description

Method for determining precoding vector, precoding processing method and base station

The embodiments of the present invention relate to communication technologies, and in particular, to a method for determining a precoding vector, a precoding processing method, and a base station. Background technique

Large Scale Multiple-Input Multiple-Output (LSM) technology is a further extension of Multiple-Input Multiple-Output (MIMO) technology. A large number of antennas are deployed on the base station side using LSM technology. , improve the throughput of wireless communication systems.

In the LSM, since the number of antennas on the base station side increases, the beam width of the transmitted signal can be narrowed by selecting an appropriate precoding matrix, the signal interference between multiple users is reduced, and the number of reusable users is increased. However, narrow beams adversely affect synchronization channels, broadcast channels, and high-speed mobile users. Therefore, in scenarios such as synchronization channels, broadcast channels, and high-speed mobile users, wide beams can be formed by precoding vectors to enhance coverage.

Due to the large number of antennas in the LSM, it is highly probable that one antenna or multiple antenna channels will fail in actual use. Since the precoding vector corresponding to the wide beam is related to the specific antenna configuration, if one or more antenna channels are faulty, the wide beam will be greatly affected, and the beam shape of the synchronization signal or the like is abruptly changed from a wide beam to an irregular shape. Not only will the coverage area of the cell appear, but it will even cause great interference to neighboring cells. Summary of the invention

Embodiments of the present invention provide a method for determining a precoding vector, a precoding processing method, and a base station to maintain a wide beam signal when an antenna fails.

In a first aspect, an embodiment of the present invention provides a base station, where the base station includes:

Multiple transmit antennas;

An antenna fault detecting module is configured to monitor whether the working state of each of the transmitting antennas is normal, and send an antenna fault to the determining device of the precoding vector when detecting that the transmitting antenna is faulty Notifying that the antenna failure notification includes a sequence number of the failed transmit antenna; the determining device of the precoding vector is configured to: if receiving the antenna fault notification sent by the antenna fault detection module, according to the The sequence number of the failed transmit antenna is updated to a precoding processing module for precoding the transmitted signal according to the updated precoding vector such that the beam shape of the transmitted signal is a wide beam.

According to a first aspect, in a first possible implementation of the first aspect, the precoding vector is obtained according to the following formula:

_W = (r. _e ^j , r _ie ^j .., r _m e ^ji ..., r _M — _ie ^j3⁄4 « ), where w is the precoding vector, M is the number of transmitting antennas, r _m is The amplitude of the precoding vector, ^ is the phase of the precoding vector

Where i is the number of iterations, _ri T is the r _m value of the ith iteration, ίΤ) is the value of the ith iteration, ^ and ^ are randomly generated, respectively, and 0 ≤ ^ ≤ 1; h is the control factor of the iteration speed , is the integral length, and is the upper and lower limits of the coverage of the base station, respectively, c _m = r _m c _m = r _m ef„W =∑r _n e ^JP f <p) = p^^ , d/ is the antenna spacing and The wavelength ratio is the jitter factor, and E is the set of sequence numbers of the failed transmitting antenna.

According to the first aspect or the first possible implementation manner of the first aspect, in the second possible implementation manner of the first aspect, the transmitting signal is a synchronization signal or a broadcast signal.

In a second aspect, an embodiment of the present invention provides a method for determining a precoding vector, where the method for determining a precoding vector includes:

Obtain initial parameters and the sequence number of the failed antenna;

Determining a precoding vector according to the initial parameter and a sequence number of the faulty antenna; wherein the initial parameter includes an antenna number, a base station coverage range, an antenna spacing, and a wavelength ratio. According to the second aspect, in a first possible implementation manner of the second aspect, the precoding direction w = (r ₀ e ^j3⁄4 , r _ie ^j ^ ,...,r _m e ^j3⁄4 ,...,v _M _^ ) , where w is the precoding vector, M is the number of transmitting antennas, r _m is the amplitude of the precoding vector, ^ is the phase of the precoding vector,

Where i is the number of iterations, _ri is the r _m value of the ith iteration, is the value of the i-th iteration, _r r and respectively are randomly generated, and o ≤ _{ri r} ≤ i _; h is the control factor of the iteration speed, For the integration step, A and % are the upper and lower limits of the coverage of the base station, respectively, c _m =

Άΐλ is the antenna spacing to wavelength ratio, which is the jitter factor, and Ε is the set of sequence numbers of the faulty antenna. In a third aspect, an embodiment of the present invention provides a precoding processing method, where the precoding processing method includes:

If the antenna failure notification is received, the sequence number of the failed transmitting antenna is obtained according to the antenna failure notification; wherein the antenna failure notification includes a sequence number of the failed transmitting antenna; and according to the failed transmitting antenna Serial number, using the determining method of the precoding vector according to claim 4 to update the precoding vector;

The transmitted signal is precoded according to the updated precoding vector such that the beam shape of the transmitted signal is a wide beam.

According to a third aspect, in a first possible implementation of the third aspect, the precoding vector is obtained according to the following formula:

w = (r ₀ e ^j3⁄4 , r _ie ^j ^ ,...,r _m e ^j ^ ,...,v _M _^ ) , where w is the precoding vector, M is the number of transmitting antennas, r _m is the amplitude of the precoding vector, ^ is the phase of the precoding vector, ^ and ^ are calculated, and the iteration formulas are as follows:

= max min

Where i is the number of iterations, _ri T is the r _m value of the ith iteration, ίΤ) is the value of the ith iteration, ^ and respectively are randomly generated, and o ≤ _{ri r} ≤ i; h is the control factor of the iteration speed , for the integral, A and % are the upper and lower limits of the coverage of the base station, respectively, - ≤ _{φ1 < φ1} ≤ , _c ~ _{m = e} w ^,

, f„ = £ O ⁿ⁽ , f _{w W} = pe—, d/ is the antenna spacing to wavelength ratio, which is the jitter factor, and E is the set of sequence numbers of the faulty antenna.

According to the third aspect or the first possible implementation manner of the third aspect, in a second possible implementation manner of the third aspect, the transmitting signal is a synchronization signal or a broadcast signal.

The method for determining a precoding vector, the precoding processing method, and the base station provided by the embodiment of the present invention, by detecting a failure of one or more of the transmitting antennas, updating the precoding vector according to the sequence number of the transmitting antenna that is faulty, and Performing precoding processing on the transmitted signal according to the updated precoding vector, so that the beam shape of the transmitted signal is a wide beam, so that the wide beam signal can be maintained when the transmitting antenna fails, and the antenna fault is eliminated to cause the wide beam signal. Impact. BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a schematic structural diagram of a base station according to an embodiment of the present invention;

2 is a flowchart of a method for determining a precoding vector according to an embodiment of the present invention;

FIG. 3 is a flowchart of a precoding processing method according to an embodiment of the present invention;

4 is a schematic diagram of a beam of a broadcast signal when a transmitting antenna fails in the prior art; FIG. 5 is a beam schematic diagram of a broadcast signal according to a precoding processing method provided by an embodiment of the present invention;

1 is a schematic structural diagram of a base station according to an embodiment of the present invention. As shown in FIG. 1, the base station 1 provided by the embodiment of the present invention includes: a plurality of transmitting antennas 11, an antenna fault detecting module 12, a precoding direction determining device 13 and a precoding processing module 14, wherein:

The antenna fault detecting module 12 is configured to monitor whether the working state of each of the transmitting antennas is normal, and, when detecting that the transmitting antenna fails, send the determining device 13 to the precoding vector. An antenna failure notification, the antenna failure notification includes a sequence number of the failed transmission antenna; the precoding vector determining device 13 is configured to receive the antenna failure notification sent by the antenna failure detection module 12, And updating the precoding vector according to the sequence number of the failed transmitting antenna;

The precoding processing module 14 is configured to perform precoding processing on the transmit signal according to the updated precoding vector, so that the beam shape of the transmit signal is a wide beam.

Specifically, the base station 1 provided by the embodiment of the present invention may adopt a LSM technology, and multiple transmit antennas 11 are deployed; the base station 1 performs precoding processing on the transmit signal by using a precoding vector corresponding to the wide beam, so that the transmit signal is The beam shape is a wide beam, and upon detecting a failure of one or more of the plurality of transmit antennas 11, recalculating the precoding vector according to the initial parameters and the sequence number of the failed transmit antenna, according to the update The pre-coding vector performs a pre-coding process on the transmit signal, so that the beam shape of the transmit signal is maintained as a wide beam. The transmit signal may be, for example, a synchronization signal or a broadcast signal. The initial parameters may include: ^1, base station coverage A ~ %, antenna spacing and wavelength ratio.

The base station provided by the embodiment of the present invention updates the precoding vector according to the sequence number of the failed transmitting antenna when detecting one or more of the transmitting antennas, and performs the transmitting signal according to the updated precoding vector. The precoding process is such that the beam shape of the transmitted signal is a wide beam, so that the wide beam signal can be maintained when the transmitting antenna fails, and the influence of the antenna failure on the wide beam signal is eliminated.

Optionally, the precoding vector is _W = (r. _E J r _ie ..., r _m e ^j ..., r _M — ^ ), where M is the number of transmitting antennas, and r _m is the pre- The amplitude of the code vector, e _m is the phase of the precoding vector, and ^ and ^ are calculated in an iterative manner. The iterative formula is as follows:

: max min άφ,Ι

II d ) +2h / "e ^h l" ^P )- ^f " ^P )| ²

Where i is the number of iterations; _ri T is the r _m value of the ith iteration, which is the ^^ value of the ith iteration, and is randomly generated, respectively, and o ≤ _{ri r} ≤ i _; h is the control factor of the iteration speed, The value can be 1; the integration step size; and % are the upper and lower limits of the coverage of the base station, respectively - 2 ^≤ ^ ^<< ^ 2 =∑r _n e άΐλ is the antenna spacing to wavelength ratio; ρ is the jitter factor; Ε is the set of sequence numbers of the failed transmitting antenna.

FIG. 2 is a flowchart of a method for determining a precoding vector according to an embodiment of the present invention. As shown in FIG. 2, a method for determining a precoding vector according to an embodiment of the present invention includes:

201. Obtain an initial parameter and a sequence number of the faulty antenna.

202. Determine, according to the initial parameter and the sequence number of the faulty antenna, an implementation body of the method for determining a precoding vector that is provided by the embodiment of the present invention, which may be a base station provided by any embodiment of the present invention. The initial parameters may include the number of antennas, the antenna spacing and wavelength ratio, and the coverage of the base station.

FIG. 3 is a flowchart of a precoding processing method according to an embodiment of the present invention. As shown in FIG. 3, the precoding processing method provided by the embodiment of the present invention includes:

301. If an antenna failure notification is received, obtain a sequence number of the failed transmitting antenna according to the antenna failure notification, where the antenna failure notification includes a sequence number of the failed transmitting antenna;

302. Update a precoding vector by using a method for determining a precoding vector provided by any embodiment of the present invention according to the sequence number of the failed transmitting antenna.

303. Perform a precoding process on the transmit signal according to the updated precoding vector, so that a beam shape of the transmit signal is a wide beam.

Specifically, the executor of the precoding processing method provided by the embodiment of the present invention may be a base station provided by any embodiment of the present invention; the transmitting signal may be, for example, a broadcast signal or a synchronization signal. Taking the broadcast signal as an example, when each transmitting antenna of the base station adopting the LSM technology is in a normal working state, the broadcast signal is pre-coded by the base station by using the precoding vector to form a wide beam signal, which can enhance signal coverage. When one or more transmitting antennas fail, the base station updates the precoding vector in real time according to the sequence number of the failed antenna, so that the beam shape of the broadcast signal is restored to a wide beam, which ensures signal coverage and is realized at the transmitting antenna. The wide beam signal can still be maintained in the event of a fault, eliminating the effects of antenna faults on the wide beam signal.

On the basis of the above embodiments, the method for determining the precoding vector, the precoding processing method and the implementation process of the base station provided by the present invention are described below through several specific embodiments.

Scenario: The number of transmit antennas deployed on the base station side is 16=16, and the number is 0~15. With a uniform linear array, the antenna spacing is half of the wavelength, and the upper and lower limits of the coverage of the base station and the % coverage are respectively -^ ~; when the transmitting antennas are all in a fault-free state, the base

2 2 2 2

The station generates a wide beam broadcast signal through a precoding vector corresponding to the wide beam to enhance signal coverage.

It is assumed that the antenna No. 4 cannot work due to a malfunction during the operation of the base station. FIG. 4 is a schematic diagram of a beam of a broadcast signal when a transmitting antenna fails in the prior art. As shown in FIG. 4, the beam shape of the broadcast signal is abruptly changed from a wide beam to an irregular shape due to the failure of the antenna No. 4, thereby causing a coverage hole in the service range of the base station, and also causing a large impact on the adjacent cell. interference.

According to the method for determining a precoding vector according to an embodiment of the present invention, when the antenna No. 4 fails, the precoding vector wr ₀ e ^j , r er ₁₅ e ^{j3⁄4 is recalculated} according to the initial parameter and the sequence number 4 of the failed antenna. Where r _m is the amplitude of the precoding vector w, and e _m is the phase of the precoding to w, and the iterative formula for calculating ^ is as follows:

1

Where i is the number of overlaps, c _m

, f _w (^) = ∑r _n e r< ¹⁺¹⁾ is the r _m value of the ith iteration, ten " is the value of the ith iteration, _fl T and respectively are randomly generated, and o ≤ ^ ≤ i; The integration step size is 0.001, the jitter factor is 0.75, and the antenna spacing is proportional to the wavelength (1/λ = 0.5;

The initial value of the amplitude (.) ~ 4. )): 1.000, 1.000, 1.000, 1.000, 0.000, 1.000, 1.000, 1.000, 1.000, 1.000, 1.000, 1.000, 1.000, 1.000, 1.000, 1.000.

The initial phase values are: -0.4916, 2.6121, 1.8360, 2.8871, 0.9785,

-2.9172, 2.1936, 2.7269, 1.1230, 1.6194, 1.5276, -0.6772, 0.9769, -2.0660, 1.2946, -2.9416ο

The amplitude and phase of the updated precoding vector w calculated according to the formula are as follows: The amplitude of w (r ₀ ~ r ₁₅ ) is: 0.110, 0.216, 0.070, 0.462, 0.000, 1.000, 0.662, 1.000, 1.000, 1.000 , 1.000, 0.945, 0.106, 0.289, 0.131, 0.197.

The phase of w (radian) ~ ₅ ) are: 1.30, 2.64, 2.10, 2.16, 0.00, 1.24, 1.75, 0.82, 2.35, -1.29, -2.17, 1.51, -0.95, -1.33, -0.73, 1.82. FIG. 5 is a schematic diagram of a beam of a broadcast signal using a precoding processing method according to an embodiment of the present invention. As shown in FIG. 5, the base station uses the precoding processing method provided by the embodiment of the present invention to update the precoding vector required by the base station to perform precoding processing on the broadcast signal according to the sequence number of the faulty antenna when the transmitting antenna fails. In order to restore the beam shape of the broadcast signal to a wide beam, signal coverage is ensured, and the wide beam signal can be maintained when the transmitting antenna fails, and the influence of the antenna failure on the wide beam signal is eliminated.

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 for explaining the technical solutions of the present invention, and are not intended to be limiting thereof; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art will understand that The technical solutions described in the foregoing embodiments may be modified, or some or all of the technical features may be equivalently replaced; and the modifications or substitutions do not deviate from the technical solutions of the embodiments of the present invention. range.

Claims

claims

1. A base station, characterized by including:

Multiple transmit antennas;

The antenna fault detection module is used to monitor whether the working status of each of the transmitting antennas is normal, and when a failure of the transmitting antenna is detected, an antenna fault notification is sent to the precoding vector determination device, and the antenna fault notification includes the The serial number of the failed transmitting antenna;

The device for determining the precoding vector is configured to update the precoding according to the serial number of the failed transmitting antenna to the precoding processing module if the antenna failure notification sent by the antenna failure detection module is received. The transmission signal is precoded according to the updated precoding vector, so that the beam shape of the transmission signal is a wide beam.

2. The base station according to claim 1, characterized in that the precoding vector is obtained according to the following formula:

w = (r ₀ e ^j¾ ,r _ie ^j ^ ,...,r _m e ^j ^ ,...,τ _Μ _^ ) , where w is the precoding vector, M is the number of transmitting antennas, r _m is the amplitude of the precoding vector, ^ is the phase of the precoding vector, ^ and ^ are calculated in an iterative manner, and the iteration formula is as follows:

Among them, i is the number of iterations, _ri T is the r _m value of the i-th iteration, is the ^ value of the i-th iteration, ^ and ^ are randomly generated respectively, and 0≤^≤1; h is the control factor of the iteration speed, for points

, length, A and % are the upper and lower limits of base station coverage respectively, c _m =

c _m , άΐλ is the antenna spacing and

The wavelength ratio is the jitter factor, and E is the sequence number set of the failed transmitting antenna.

3. The base station according to claim 1 or 2, characterized in that the transmitted signal is a synchronization signal or a broadcast signal.

4. A method for determining a precoding vector, characterized by: including:

Get the initial parameters and the serial number of the failed antenna; The precoding vector is determined according to the initial parameters and the serial number of the failed antenna; wherein the initial parameters include the number of antennas, base station coverage, antenna spacing and wavelength ratio.

5. The method for determining the precoding vector according to claim 4, characterized in that the precoding vector is obtained according to the following formula:

w = (r ₀ e ^j¾ ,v^ ,..., v _m e ^ie - ,...,v _M _,e^ ) , where w is the precoding vector, M is the number of transmitting antennas, r _m is the amplitude of the precoding vector, ^ is the phase of the precoding vector, and the iterative formulas are as follows:

Among them, i is the number of iterations, _ri T is the r _m value of the i-th iteration, is the ^ value of the i-th iteration, and are randomly generated respectively, and o _≤ri r≤i; h is the control factor of the iteration speed, and is integral

, length, and are respectively the upper and lower limits of the base station coverage, 2 ≤ 2

=∑r _n e (φ) = ρο^ ^ , άΐλ is the ratio of antenna spacing to wavelength, is the jitter factor, and Ε is the sequence number set of failed antennas.

6. A precoding processing method, characterized by including:

If an antenna failure notification is received, the serial number of the failed transmitting antenna is obtained according to the antenna failure notification; wherein, the antenna failure notification includes the serial number of the failed transmitting antenna; according to the serial number of the failed transmitting antenna Serial number, update the precoding vector using the method for determining the precoding vector as claimed in claim 4;

The transmission signal is precoded according to the updated precoding vector, so that the beam shape of the transmission signal is a wide beam.

7. The precoding processing method according to claim 6, characterized in that the precoding vector is obtained according to the following formula:

w = (r ₀ e ^j r ₁ e^ ,.., r _m e^ ,..,r _M _ ₁ e ^j ^ ) , where w is the precoding vector, M is the number of transmitting antennas, r _m is the amplitude of the precoding vector, ^ is the phase of the precoding vector, ^ and ^ are calculated in an iterative manner, and the iterative formulas are as follows:

ll ll Among them, i is the number of iterations, _ri T is the r _m value of the i-th iteration, ίΤ) is the value of the i-th iteration, and are randomly generated respectively, and o _≤ri r≤i; h is the control of the iteration speed factor, is the integral

8. The precoding processing method according to claim 6 or 7, characterized in that the transmitted signal is a synchronization signal or a broadcast signal.