WO2010099660A1

WO2010099660A1 - Method and device for implementing omnidirectional coverage for public channel

Info

Publication number: WO2010099660A1
Application number: PCT/CN2009/070647
Authority: WO
Inventors: 杨学志; 蒋伟
Original assignee: 华为技术有限公司
Priority date: 2009-03-05
Filing date: 2009-03-05
Publication date: 2010-09-10
Also published as: WO2010099674A1; WO2010099756A1

Abstract

A method for implementing omnidirectional coverage for public channel includes: obtaining a fundamental weight vector that is composed of M weight coefficients, wherein M is the number of antennas; obtaining N different phases of current public channel signal frame, wherein N is the number of time slots included in public channel signal frame; obtaining N weight vectors by transforming the fundamental weight vector according to the N different phases, wherein the N weight vectors are different and each of the N weight vectors includes M weight coefficients; when any one of the N time slots is reached, selecting one of the N weight vectors, said selected vectors differing from each other in the different time slots; weighting the public channel signals in the corresponding M antennas with the M weight coefficients included in the selected weight vector respectively, and transmitting the weighted public channel signals through the M antennas. In addition, a device for implementing omnidirectional coverage for public channel is provided.

Description

Method and device for realizing comprehensive coverage of common channel

Technical field

The embodiments of the present invention relate to the field of communications, and in particular, to a method and apparatus for implementing comprehensive coverage of a common channel.

Background technique

Since the 1990s, the wireless communication industry has experienced explosive growth. As voice, data, video and other services begin to gradually move, the demand for wireless communication system bandwidth is increasing. However, the available frequency band resources are becoming increasingly tight, so how to improve spectrum utilization becomes a key issue in wireless communication research.

Technologies that can effectively improve spectrum utilization include: multiple access, signal detection, modulation, and channel coding. Among them, the potential of multi-antenna systems (MAS) is increasingly important in wireless communications.

Smart Antennas (SAs), also known as Antenna Array Systems (AAS), are a type of multi-antenna system. The spacing of array elements of smart antennas is smaller than the correlation distance of channels. Using the signal correlation between the antenna elements, the array antenna can implement beamforming, adaptively pointing the high-enhanced narrow beam to the mobile terminal in communication, and adjusting the null-aligned interference direction.

In a cellular mobile communication system, a base station allocates a dedicated channel for each active user in a cell to carry voice, data or video services. A smart antenna-based base station generates a narrowest beam by beamforming into a dedicated channel. The narrower the beam, the more concentrated the energy, the higher the antenna gain in the direction of the mobile terminal, and the stronger the interference suppression capability in other directions.

In an actual mobile communication system, a common channel is required in the cell in addition to the dedicated channel; the common channel carries common information required by all mobile terminals in the cell, such as system information in the broadcast channel, and reference signals in the synchronization channel, Pilots, paging and common control messages in the Forward Access Channel (FACH), etc. The requirement of the common channel to cover the base station system is very different from that of the dedicated channel. The dedicated channel only needs to establish a wireless link between the base station and the mobile terminal, and the transmitted signal often interferes with other base stations or mobile terminals, so the signal coverage area ( Under the premise of covering both communication parties, the smaller the better, the better; and the common channel requires all mobile terminals in the cell to receive signals at the same time, so the base station has a good overall coverage of the entire cell. Therefore, the smart antenna system must not only generate directional beams to enhance the useful signal and suppress the interference signal, but must also generate an omnidirectional beam. Provide comprehensive coverage of the cell for the common channel.

In the prior art, there is a solution for comprehensive coverage of an array antenna, which divides the transmission time of a common channel signal into time slots, selects a set of complementary weight vectors of the pattern, and alternately uses complementary rights in consecutive time slots. The vector thus achieves full coverage of the smart antenna based cell.

However, in the above prior art, although a plurality of complementary weight vectors are alternately used, the average antenna gain of the plurality of patterns is not completely equal in different directions, but only has an approximate isotropic property, thereby causing each The performance difference of BER (Bit Error Rate) is relatively large.

Summary of the invention

The embodiment of the invention provides a method and a device for realizing comprehensive coverage of a common channel, which can realize comprehensive coverage of a common channel by a smart antenna, and realize isotropic of the antenna gain, thereby realizing signal reliability received in each direction of the cell. Consistent.

The method for implementing comprehensive coverage of a common channel provided by the embodiment of the present invention includes: acquiring a base weight vector, where the base weight vector is composed of M weight coefficients, where the M is the number of antennas; and acquiring N current common channel signal frames. Different phases, where N is the number of slots included in the common channel signal frame; transforming the basis weight vector according to the N different phases to obtain N weight vectors, the N weight vectors being different, Each of the N weight vectors includes M weight coefficients; when any one of the N time slots is reached, one of the N weight vectors is selected, and weight vectors selected by different time slots are different; The M weight coefficients in the selected weight vector respectively weight the common channel signals in the corresponding M antennas, and transmit the weighted common channel signals through the M antennas.

The apparatus for implementing comprehensive coverage of a common channel provided by the embodiment of the present invention includes: a base weight vector acquiring unit, configured to acquire a base weight vector, where the base weight vector is composed of M weight coefficients, where the M is the number of antennas; An acquiring unit, configured to acquire N different phases of the current common channel signal frame, where N is a number of slots included in the common channel signal frame; and a transform unit, configured to acquire N different phase pairs according to the phase acquiring unit The weight vector obtained by the basis weight vector obtaining unit is transformed to obtain N weight vectors, the N weight vectors are different, and the N weight vectors each comprise M weight coefficients; the weight vector selecting unit is used for When any one of the N time slots is reached, one of the N weight vectors is selected, and weight vectors selected by different time slots are different; a weighting unit is used to select by using the weight vector selecting unit M weight coefficients in the weight vector respectively correspond to the corresponding M And transmitting, by the M antennas, the weighted common channel signal.

As can be seen from the foregoing technical solutions, the embodiments of the present invention have the following beneficial effects: In the embodiment of the present invention, since different bases are selected in different time slots to convert the base weight vector, the beam pattern is continuously changed, so that In the specified direction, the antenna gain varies randomly with time, so the average value of the gain exhibits isotropic, so that the reliability of signals received in all directions in the cell is consistent.

DRAWINGS

1 is a flowchart of a method for implementing comprehensive coverage of a common channel in an embodiment of the present invention;

2 is a beam pattern in an embodiment of the present invention;

FIG. 3 is a schematic diagram of an apparatus for implementing full coverage of a common channel according to an embodiment of the present invention; FIG. 4 is another schematic diagram of an apparatus for implementing full coverage of a common channel according to an embodiment of the present invention; FIG.

FIG. 6 is a schematic diagram of a simulation experiment in an embodiment of the present invention.

detailed description

The method for implementing comprehensive coverage of a common channel in the embodiment of the present invention includes:

Obtaining a basis weight vector, the basis weight vector is composed of M weight coefficients, the M is the number of antennas; acquiring N different phases of the current common channel signal frame, where N is a time slot included in the common channel signal frame Number

Converting the basis weight vector according to the N different phases to obtain N weight vectors, wherein the N weight vectors are different, and each of the N weight vectors includes M weight coefficients;

When any one of the N time slots is reached, one of the N weight vectors is selected, and the weight vectors selected by different time slots are different;

And respectively weighting the common channel signals in the corresponding M antennas by using the M weight coefficients in the selected weight vectors, and transmitting the weighted common channel signals through the M antennas.

In this embodiment, since the different weights are selected in different time slots to convert the basis weight vector, The beam pattern is changed so that the antenna gain varies randomly with time in a specified direction, so the average value of the gain exhibits isotropic, so that the reliability of signals received in all directions in the cell is consistent.

For ease of understanding, the method for realizing the comprehensive coverage of the common channel in the embodiment of the present invention is described in detail below with reference to the accompanying drawings. Referring to FIG. 1, the method for implementing comprehensive coverage of the common channel in the embodiment of the present invention includes:

101. Divide each frame in a transmission time of a common channel signal into N time slots;

In this embodiment, when the common channel signal needs to be transmitted through the smart antenna, the transmission time of the common channel signal is first divided into frames, and then each frame is divided into N time slots.

102. Obtain a base weight vector.

In this embodiment, a base weight vector = [ _Wl w ₂ ... w _M ] ^{T is} first designed, and the basis weight vector is

The weighting coefficients are recorded as w _m , m = l,...,M , one weighting coefficient corresponds to one transmitting channel, one transmitting channel corresponds to one antenna, and Μ is a positive integer greater than 1.

The coverage angle of the beam generated by the weight vector beamforming should reach a preset threshold, and the beam flatness should be higher than the preset threshold in the angular dimension, that is, the peak-to-average ratio is lower than the preset threshold, that is, the beam It should have the characteristics of wide coverage angle, flat beam, and low peak-to-average ratio.

At the same time, in order to reduce the cost and avoid using high power amplifiers, the transmit power of each antenna can be required to be equal, that is, the modulus of each weight coefficient in the basis weight vector is equal, | _WI | = |W ₂ | = ... = | MV |.

103. Obtain N different phases;

In this embodiment, N different phases are obtained, which respectively correspond to N time slots in the current frame. Specifically, one phase may be selected from [0, 2 τ] according to a certain criterion, and the selected phase transformations are generated. The weight vector beam pattern should be complementary, and the average antenna gain in different directions in the cell should be equalized as much as possible. The computer can search or test multiple times to find the phase that meets the requirements. For example, software such as MATLAB can be used. Select the desired phase from 0 to 2 π.

104. Transforming the basis weight vector according to each phase to obtain a weight vector;

After obtaining the basis weight vector and the two phases, the base weight vector can be transformed according to each phase to obtain one weight vector corresponding to one time slot, specifically:

Suppose there is any time slot, denoted as t, and select the phase (0, transform the base weight vector according to the following formula to generate a new weight vector (t):

w{t) = diag[\ e ^j e ^m ... _e ^j{M - ^,) w (1) Among them, the imaginary unit is recorded as, satisfying the corpus = -ι, indicating that the elements in the brackets form a diagonal matrix.

105. When any one of the time slots is reached, any one of the weight vectors is selected. In the above step 104, the weight vectors may be calculated according to the phase and the weight vector, and the weight vectors are different. And corresponding to one time slot, when a certain time slot is reached, one of the weight vectors may be selected, and the specific selection method may be:

First, the order is selected:

According to the sequence of time slots, one of the weight vectors is selected in order, for example, the first time slot selects the first weight vector, the second time slot selects the second weight vector, and so on.

Second, random selection:

In addition to the sequential selection described above, it can also be randomly selected, that is, when a certain time slot is reached, one of the weight vectors is randomly selected, but the selection needs to comply with certain criteria: Each weight vector can only be selected once. And each weight vector needs to be selected.

106. Weighting the common channel signals in the corresponding ones by using one of the selected weight vectors;

After a certain time slot determines the selected weight vector, the common channel signal is weighted, and the beam shaping is performed according to the weight vector, so the beam pattern of the time slot is:

g(e, t) = w(t) ^H a(e) = J _j w _n (t)e ^ (2)

Where "(refers to the 3 ¹ direction vector of the smart antenna array, the vector is the M-dimensional column vector, Θ represents the direction angle of the signal and the linear antenna array, and J represents the spacing of the linear array elements.

After the basis weight vector is transformed according to equation (1), the beam pattern can still maintain the characteristics of wide coverage angle, flat beam, and low peak-to-average ratio. The beam pattern is rotated by o. It should be noted that the rotation described here is described. It does not mean that the beam pattern is simply rotated by a certain angle, but by the rotation of the weight vector phase, the beam pattern is changed in shape.

Assuming that the beam pattern of the basis weight vector is as shown by the solid line 201 in Fig. 2, the beam generated by the weight vector has a wide coverage angle, a flat beam, and a low peak-to-average ratio. The beam pattern of the basis weight vector has lower gains around 30°, 150°, 210°, and 330°, and high gains around 15°, 165°, 225°, and 315°.

Select (0 = 45°, transform the basis weight vector according to formula (1). The beam pattern of the new weight vector 0 is shown by the dotted line 202 in Fig. 2; the beam generated by the new weight vector still satisfies the wide coverage angle and beam Flat, low peak-to-average ratio. The beam pattern generated by the new weight vector has a high gain around 30°, 150°, 210°, 330°, and a low gain near 15°, 165°, 225°, 315°. It can be seen that the two beam patterns are complementary. For a given direction, the high and low gains of the array antenna alternately appear. Through channel coding and interleaving techniques, the overall coverage of the common channel can be achieved.

107. Send the weighted common channel signal through the M antennas.

After the weighting of the common channel signal is completed, the weighted common channel signal is transmitted through the M antennas, and the common channel signals of the N time slots in the current frame are sequentially transmitted in order.

In this embodiment, the antenna element and the low power amplifier group existing in the smart antenna system are fully utilized, and a basis weight vector is selected to generate a beam with a wide coverage angle, a flat beam, and a low peak-to-average ratio, with a random phase pair. The basis weight vector is transformed to continuously change the beam pattern. In the specified direction, the antenna gain varies randomly with time, so the average of the gains exhibits isotropic.

It should be noted that, by using the foregoing steps, a common channel signal of one frame can be transmitted, and full coverage of the common channel is implemented, but if the common channel signal is more than one frame, the common channel signal of the next frame needs to be continuously transmitted, due to the weight vector. The larger the number, the stronger the average isotropic of the antenna gain. Therefore, in order to further improve the isotropic nature of the antenna gain average, different N weight vectors can be used in different frames instead of simply repeating the previous one. The weight vector of the frame.

In this embodiment, an inter-frame incremental phase value may be preset, and N different weight vectors of the current frame may be updated by using the inter-frame incremental phase value to obtain N different second weight vectors, which may be in the next frame. The N second weight vectors are used. Specifically, the inter-frame incremental phase values may be respectively added to the N weight vectors of the current frame to obtain N second weight vectors.

The transmission process of the N time slots in a certain frame is described in detail above. In practical applications, the common channel signal is often more than one frame. The following is an implementation in the embodiment of the present invention for the case where multiple frames may exist. A description of the method of comprehensive coverage of public channels:

The transmission time of the cell common channel signal based on the smart antenna system is divided into consecutive time frames, each frame is divided into N time slots, and each time slot includes L modulation symbols. The nth slot of the kth frame is denoted by ^, and the slot length is less than the channel correlation time, i.e., the channel fading experienced by all L symbols in each slot is constant.

First, the basis weight vector w = [ _Wl w ₂ ... w _M ] ^{T is determined} . The basis weight vector is composed of two weighting coefficients, and the weighting coefficients are recorded as w _m , = l,..., M , M weighting coefficients Corresponding to M transmit channels, M transmit The shot channel corresponds to M antennas, and M is a positive integer greater than one.

The beam generated by the weight vector beamforming should have a wide coverage angle, a flat beam, and a low peak-to-average ratio.

According to certain criteria, select one phase value ( „ ), " = 1, ... , N from [0, 2π], sequentially select a phase from (ί _η ), and base weight according to formula (1) The vector is transformed. After the transformation, the weight vector w( „), η = ί,...,Ν:

w{t _kn ) = diag[\ e ^m ^ e ^j ^ ... n = \,...,N The weight vector beam pattern generated after the transformation of the selected N phase values should be complementary, as much as possible The average antenna gains in different directions in the cell are equal, and a computer search or multiple test methods can be used to find a phase that satisfies the requirements. Each time slot of the kth frame sequentially selects w(t _kn ), the weight vector of one of "=1, ..., N is beamformed, that is, the slot selection weight vector 4, „); each time slot It is also possible to randomly select a weight vector from w(4„), but ensure that each weight vector must be used and can only be used once. A specified direction in the cell, if the antenna gain in a certain slot If the value is lower, then the gain will be higher in some other time slots in the same frame. The low gain of the time slot experiencing the beam pattern is equivalent to the deep fading of the channel in the BER performance, which can be obtained by channel coding and interleaving techniques. Eliminate the effects of.

Since the number of weight vectors is larger, the antenna gain average isotropic is stronger. Therefore, in order to further improve the isotropic of the antenna gain average, different weight vectors can be used in different frames instead of simply Reuse the weight vector of the previous frame. The processing manner in this embodiment is: selecting an inter-frame incremental phase value, and generating the phase 0 of the ₊₁ frame according to the following formula ( ₊₁ , J n = l,..., N:

<p(tk + \,n) = <p(tk,n) + S, n = l,...,N

Each time slot of the +1 frame is selected in accordance with the same method as the above-mentioned first frame, and each phase value is selected, and then transformed, and the new weight vector beam generated by the transform is used for beamforming.

The device for realizing the comprehensive coverage of the common channel in the embodiment of the present invention is specifically located in the base station. Referring to FIG. 3, the implementation of the common channel in the embodiment of the present invention is complete. One embodiment of a face covering device includes:

The base weight vector obtaining unit 301 is configured to obtain a base weight vector, where the base weight vector is composed of M weight coefficients, where the M is the number of antennas;

The phase obtaining unit 302 is configured to acquire N different phases of the current common channel signal frame, where N is the number of slots included in the common channel signal frame;

The transform unit 303 is configured to perform, according to the N different phases acquired by the phase acquiring unit 302, the base weight vector acquired by the basis weight vector acquiring unit 301 to obtain N weight vectors, where the N weight vectors are different. Each of the N weight vectors includes M weight coefficients;

The weight vector selection unit 304 is configured to: when any one of the N time slots is reached, select one of the N weight vectors, and the weight vectors selected by different time slots are different;

The weighting unit 305 is configured to weight the common channel signals in the corresponding M antennas by using the M weight coefficients in the weight vector selected by the weight vector selecting unit 304;

The sending unit 306 is configured to send the weighted common channel signal by using M antennas. For ease of understanding, the following describes an apparatus for implementing comprehensive coverage of a common channel in the embodiment of the present invention. Referring to FIG. 4, another embodiment of the apparatus for implementing comprehensive coverage of a common channel in the embodiment of the present invention includes:

a dividing unit 401, configured to divide each frame in a transmission time of the common channel signal into N time slots;

The base weight vector obtaining unit 402 is configured to obtain a base weight vector, where the base weight vector is composed of M weight coefficients, where the M is the number of antennas;

a phase acquisition unit 403, configured to acquire N different phases;

The transform unit 404 is configured to transform, according to each phase acquired by the phase acquiring unit 403, the base weight vector acquired by the basis weight vector obtaining unit 402 to obtain N weight vectors, where the N weight vectors are different. Each of the N weight vectors includes M weight coefficients;

The weight vector selection unit 405 is configured to select any one of the N weight vectors when the any one of the N time slots is reached, and the weight vectors selected by the different time slots are different;

The weighting unit 406 is configured to weight the common channel signals in the corresponding M antennas by using the M weight coefficients in the weight vector selected by the weight vector selecting unit;

a sending unit 407, configured to send, by using the M antennas, the weighted common channel signal number.

If the common channel signal is sent to more than one frame, the apparatus in this embodiment may further include:

An incremental acquisition unit 408, configured to acquire a preset inter-frame incremental phase value;

The phase updating unit 409 is configured to update the N phases acquired by the phase acquiring unit 403 according to the inter-frame incremental phase value acquired by the incremental acquiring unit 408 to obtain N second phases, and indicate the transforming unit 404. Transforming the N basis weight vectors according to the N second phases to obtain N weight vectors.

The weight vector selection unit 405 in this embodiment may further include:

a sequence selecting unit 4051, configured to sequentially select corresponding weight vectors of the N weights according to a sequence of N time slots;

Or,

The random selection unit 4052 is configured to randomly select one weight vector from the N weight vectors according to the sequence of N time slots, and the weight vectors selected in different time slots are different.

In this embodiment, the basis weight vector obtaining unit 402 selects a basis weight vector to generate a beam having a wide coverage angle, a flat beam, and a low peak-to-average ratio, and the phase acquiring unit 403 acquires the phase, and the phase is obtained by the transform unit 404 with a random phase. The weight vector is transformed to continuously change the beam pattern. In the specified direction, the antenna gain varies randomly with time, so the average of the gains exhibits isotropic. This embodiment implements the antenna gain isotropic of the full coverage of the smart antenna.

The following describes the data transceiving process in a specific example in conjunction with the transceiver system in this embodiment:

Assuming a linear array antenna of 8 elements, choose the following base weight vector:

w = [l 1 1 -1 1 -1 -1 ι] ^τ

Let the spacing of the antenna elements be half a wavelength ^/ = /2. According to formula (2), the beam direction of the weight vector can be obtained. For details, see Figure 2. The beam pattern of the base weight vector covers most of the angles. , the beam is flat, and the peak-to-average ratio is low.

Referring to FIG. 5, FIG. 5 is a transceiver system according to an embodiment of the present invention. After a common channel signal passes through a code modulation unit 501 at a transmitting end, a symbol partition is obtained, and each block includes one modulation symbol, represented by a vector d.

Let the received signal be represented as x:

_" ■]

I X- ... N J

After the obtained symbols are divided into blocks, the framing is performed by the framing unit 502, and then the beamforming unit 503 is used for beamforming. In addition, the OFDM modulation unit 504 can perform orthogonal frequency division multiplexing (OFDM, Orthogonal Frequency Division Multiple). The modulation is then transmitted through channel 505, demodulated by the OFDM demodulation unit 506 to the receiving end, and entered into the receiver 507.

It should be noted that after beamforming, multipath channel fading, and additive white noise (AWGN), the received signal can be expressed as:

x = -^HG d + n= -^A d + n where H is the channel response matrix, if the channel is a single-path channel, such as a narrow-band signal in a Time Division Multiple Access (TDMA) system, Or an Orthogonal Frequency Division Multiple Access (OFDMA) system, where the channel response matrix is a diagonal matrix:

H = diag[f 3⁄4 ... h _N ] ^T

Among them, are the channel response coefficients of each time slot in each frame. The beamforming gain matrix is denoted as G and is determined by the beam pattern in the specified direction.

G = diag[g ₁ g ₂ ... g _N ] ^T

Among them, the beam-forming antenna gain of N weight vectors used in N time slots, respectively, can be calculated by the following formula:

g„ =∑w _m e , η = 1,...,Ν To simplify the labeling, matrix A is used to represent the product of matrices G and H, and A is also a diagonal matrix.

A = H G

Finally, in the decoding and demodulating unit 508, the transmitted data symbols can be demodulated by a typical minimum mean square error (MMSE) algorithm, and the specific demodulation algorithm is as follows: The above describes the transmission process of the common channel signal, wherein The operation performed in the beamforming unit 503 is a method for realizing the comprehensive coverage of the common channel as described in the foregoing method embodiment, and the specific process It is not mentioned here.

In order to verify that the above solution can achieve the desired effect, the simulation verification process in the embodiment of the present invention is described below:

The method for omnidirectional coverage of the common channel of the cell based on the smart antenna proposed by the embodiment of the present invention is simulated on the MATLAB/Simulink platform, and the selected simulation parameters are all defined in the actual communication system or defined in the standard, as shown in the following table.

Table 1 Simulation parameter table

Simulation parameter parameter value

Source Bernoulli binary source, 0 and 1 distribution, output bit rate 1 Mbps, simulation frame length 288 bits

The LDPC code defined in the channel coding WiMAX (IEEE802.16e) standard has a code length of n=576, a code rate of 1/2, a hard decision, and a maximum iteration of 50 times. The convolutional code defined in the WiMAX (IEEE 802.16e) standard is also selected. (CC), code rate 1/2, constraint length equal to 7, octal coding polynomial is [133 171], Viterbi decoding

Interleaving matrix interleaving 288x120

Modulation 4-QAM (QPSK), Gray mapping, with LDPC code, demodulator (soft) output Log-Likelihood Ratio (LLR), when using convolutional code, the demodulator adopts hard decision

OFDM FFT/IFFT length 128, cyclic prefix length 16

Channel estimation Ideal channel estimation, the transmitter inserts impulse pilots (power is much larger than the transmitted symbol power)

Channel Rayleigh+AWGN, Rayleigh channel adopts VA channel defined in 3GPP (see Table 2 for specific parameters), Doppler shift is set to 100 Hz; Signal to Noise Ratio (SNR) of AWGN channel Simulation range: [-2 dB, 18 dB]

Smart antenna linear array antenna (ULA), 8 elements, array element spacing ί/ = 1/2, base weight vector w = [l 1 1 -1 1 -1 -1 ί] ^τ , initial transformation phase φ _η " = 1,...,4 is equal to 60°, 120°, 240°, 300°, interframe increment phase = 37° Receiver MMSE reception, x = (H ^H H + a ² I) ¹ H ^H r Number of slots N=4, slot length L=128

Table 2 Rayleigh Channel Parameter Table

Referring to the simulation result curve in Fig. 6, the single antenna and the smart antenna omnidirectional beam are simulated. Each scheme adopts LDPC code and convolutional code, and four sets of simulations are used.

Wherein, curve 601 is a performance curve when a single antenna adopts a convolutional code, curve 602 is a performance curve when a smart antenna omnidirectional beam adopts a convolutional code, and curve 603 is a performance curve when a single antenna adopts an LDPC code, and curve 604 is an intelligent curve. The performance curve when the omnidirectional beam of the antenna adopts the LDPC code.

In the simulation experiment, a plurality of different receiving angles of the cell are randomly selected. The simulation results show that the reliability of the received signals in different directions in the cell is completely consistent, and there is no correlation with the channel coding, which proves that the smart antenna array is omnidirectional in the embodiment of the present invention. Covered isotropic. As shown in Figure 6, the BER performance of the omnidirectional beam of the smart antenna is only 1 ~ 2 dB of the received signal power signal-to-noise ratio (SNR) loss of a single antenna. In the case of weaker coding (convolutional code), the received signal SNR loss is about 2 dB compared to the reliability of a single antenna. In the case of stronger coding (LDPC code), the signal-to-noise ratio difference between the single antenna and the smart antenna omnidirectional beam is only 1 dB.

The omnidirectional beamforming algorithm in the smart antenna array system proposed by the embodiment of the present invention can provide good omnidirectional coverage for the common channel of the cell.

It will be understood by those skilled in the art that all or part of the steps of implementing the foregoing embodiments may be performed by a program to instruct related hardware, and the program may be stored in a computer readable storage medium. , including the following steps:

Obtaining a basis weight vector, where the basis weight vector is composed of M weight coefficients, and the M is the number of antennas; Obtaining N different phases of the current common channel signal frame, where N is the number of time slots included in the common channel signal frame;

The above-mentioned storage medium may be a read only memory, a magnetic disk or an optical disk or the like.

The method and device for implementing the comprehensive coverage of the common channel provided by the present invention are described in detail above. For those skilled in the art, according to the idea of the embodiment of the present invention, the specific implementation manner and the application range may be changed. In the above, the contents of the specification are not to be construed as limiting the invention.

Claims

Rights request

A method for realizing comprehensive coverage of a common channel, comprising:

2. The method according to claim 1, wherein the method further comprises: acquiring a preset interframe incremental phase value;

The phase of the different common channel signal frames is updated in accordance with the phase and the interframe progressive phase value.

The method according to claim 1, wherein the step of transforming the basis weight vector according to N different phases to obtain N weight vectors comprises:

N weight vectors are obtained by the following formula:

w(t) = diag[\ e ^m) e ... „ * w

Where w is the basis weight vector, for a time slot t, the phase is (t), j is the imaginary unit, corpse = -1 , indicating that the diagonal matrix is formed by the elements in parentheses, w(t) is the weight vector, t The value ranges from 1 to N.

The method according to any one of claims 1 to 3, characterized in that the modulo of the M weight coefficients in the base weight vector are equal.

The method according to any one of claims 1 to 3, wherein the step of acquiring a weight vector comprises:

The basis weight vector is selected such that the coverage angle of the beam after the beamforming by the basis weight vector reaches a preset threshold, and the beam flatness is higher than the preset threshold in the angular dimension, that is, the peak-to-average ratio is lower than the preset threshold.

The method according to any one of claims 1 to 3, wherein the step of acquiring N different phases comprises: Select a different phase from 0 to 2π according to the preset algorithm.

The method according to any one of claims 1 to 3, wherein, when the any one of the time slots is reached, the step of selecting one of the weight vectors comprises:

Selecting corresponding weight vectors in the weight vectors in sequence according to the sequence of time slots; or

According to the sequence of time slots, a weight vector is randomly selected from the weight vectors, and the weight vectors selected in different time slots are different.

8. The method according to claim 2, wherein the updating the phase of the different common channel signal frames according to the phase and the increasing phase value between the frames comprises:

Adding the interframe progressive phase values to the one of the phases respectively yields a second phase.

9. A device for realizing comprehensive coverage of a common channel, comprising:

a base weight vector obtaining unit, configured to obtain a base weight vector, where the base weight vector is composed of one weight coefficient, where the number is an antenna;

a phase acquiring unit, configured to acquire a different phase of a current common channel signal frame, where Ν is a number of time slots included in the common channel signal frame;

a transform unit, configured to transform, according to the different phases acquired by the phase acquiring unit, the base weight vector obtained by the base weight vector acquiring unit to obtain a weight vector, where the weight vectors are different, Each of the weight vectors each includes a weight coefficient;

a weight vector selecting unit, configured to select one of the one of the weight vectors when the one of the one time slots is reached, and the weight vectors selected by the different time slots are different;

a weighting unit, configured to weight, by using the weight coefficients of the weight vectors selected by the weight vector selecting unit, the common channel signals in the corresponding ones of the antennas;

And a sending unit, configured to send the weighted common channel signal by using the two antennas.

The device according to claim 9, wherein the device further comprises: an incremental acquiring unit, configured to acquire a preset inter-frame incremental phase value;

And a phase updating unit, configured to update phases of different common channel signal frames according to the phase and the inter-frame incremental phase value.

The device according to claim 9 or 10, wherein the weight vector selection unit comprises: a sequence selection unit, configured to sequentially select corresponding weight vectors of the N weight vectors according to a sequence of N time slots;

Or,

The random selection unit is configured to randomly select one weight vector from the N weight vectors according to the sequence of N time slots, and the weight vectors selected in different time slots are different.