CN-122027416-A - BPSK signal processing method based on circular antenna array and adaptive beam forming

CN122027416ACN 122027416 ACN122027416 ACN 122027416ACN-122027416-A

Abstract

The invention discloses a BPSK signal processing method based on a circular antenna array and self-adaptive beam forming, and relates to the technical field of array signal processing and digital communication simulation. The method comprises the steps of constructing a full-link integrated simulation environment, generating BPSK radio frequency signals formed by root raised cosine, superposing noise and constructing a guide vector to form an array signal, evaluating signal-to-noise ratio gains and pointing accuracy of different array configurations through traversing full space angles, and determining an optimal array. For the segmented dynamic input signals, weight vectors of various adaptive criteria are calculated in real time to perform dynamic beam forming and demodulation. The system prefers the best adaptive criterion according to the output signal-to-noise ratio and the pointing accuracy index. The method realizes closed loop verification from modulation emission, dynamic beam forming to demodulation evaluation, can cooperatively optimize the array configuration and algorithm under a high-fidelity dynamic channel, remarkably improves the signal-to-noise ratio gain and pointing precision of the system, and provides reliable simulation reference and engineering guidance for real-time array processing.

Inventors

ZHANG JIEBIN
LIU RENWEI
ZHAO YUN
WANG HAO

Assignees

北京航空航天大学

Dates

Publication Date: 20260512
Application Date: 20260324

Claims (9)

1. A BPSK signal processing method based on a circular antenna array and adaptive beamforming, comprising: generating a periodic BPSK baseband signal, adopting root raised cosine pulse shaping treatment, and performing up-conversion to radio frequency for two times to generate a radio frequency signal; Generating a noise matrix of the radio frequency signal by adopting Gaussian white noise, constructing a guide vector of each antenna array, and generating an array signal matrix after combining; performing conventional beam forming on each array signal matrix to obtain beam signals, performing down-conversion, low-pass filtering, coherent demodulation and matched filtering on the beam signals, and performing sampling judgment to obtain an output end bit stream; calculating the output signal-to-noise ratio of each antenna array by traversing the full space angle, calculating the signal-to-noise ratio gain, the pointing precision and the distinguishing degree according to the beam response characteristics, analyzing the performance of each antenna array, and determining the optimal array; Generating a sectional dynamic input signal, calculating a variable steering vector of an optimal array, and generating a sectional dynamic array signal matrix; Generating weight vectors of the respective adaptation criteria in real time according to the dynamic input signals and the dynamic array signal matrix; carrying out beam forming on the dynamic array signal matrix according to the weight vector of each adaptation criterion to generate a dynamic beam signal, and recovering the dynamic beam signal into a binary bit stream to generate a dynamic output signal; According to the weight vector of each adaptation criterion, traversing the full space angle, calculating the output signal-to-noise ratio of each adaptation criterion, calculating the signal-to-noise ratio gain and the pointing precision, and selecting the self-adaptation criterion with the maximum signal-to-noise ratio gain and the minimum pointing precision as the optimal criterion; The BPSK signal is processed using an optimal array and an optimal criteria.
2. The BPSK signal processing method based on the circular antenna array and the adaptive beamforming according to claim 1, wherein the generating the periodic BPSK baseband signal, performing a root raised cosine pulse shaping process, and performing up-conversion to radio frequency twice, generates a radio frequency signal, comprises: Generating an input bit stream by adopting a periodic alternating code pattern as an original input bit stream; Converting the bit stream at the input end into a bipolar baseband symbol sequence by adopting constellation mapping operation of binary phase Shift keying; Performing root raised cosine pulse shaping processing on the bipolar baseband symbol sequence to generate a continuous-time baseband pulse signal; Moving the baseband pulse signal to an intermediate frequency band by complex exponential modulation to generate an intermediate frequency signal; And performing frequency spectrum shifting on the intermediate frequency signal by adopting a secondary up-conversion mechanism to generate a radio frequency signal.
3. The BPSK signal processing method based on the circular antenna array and the adaptive beamforming according to claim 1, wherein the generating the noise matrix of the radio frequency signal using gaussian white noise, and constructing the steering vector of each antenna array, generating the array signal matrix after combining, comprises: according to the radio frequency signal, introducing uniform space additive Gaussian white noise, and carrying out power normalization to generate a noise matrix; constructing a steering vector of each antenna array, wherein the expression is as follows: In the formula, The direction angle and the pitch angle of the signal are respectively; is the wavelength of the radio frequency signal; is the first The distance between each array element and the origin of coordinates; Unit vector upward for signal is at the first Projecting the array elements in the direction; multiplying the steering vector with the radio frequency signal and adding a noise matrix to obtain an array signal matrix of the input end.
4. The BPSK signal processing method based on the circular antenna array and the adaptive beamforming according to claim 1, wherein performing conventional beamforming on each array signal matrix to obtain a beam signal, performing down-conversion, low-pass filtering, coherent demodulation, and matched filtering on the beam signal, and performing sampling decision to obtain an output end bit stream, includes: Performing spatial filtering on the array signal matrix by adopting a digital beam forming technology to generate a beam signal; mixing the beam signal with the intermediate frequency to generate a complex intermediate frequency signal; Removing high-frequency spurious components and out-of-band noise in the complex intermediate frequency signals by adopting a low-pass filter to generate intermediate frequency useful signals; performing coherent demodulation on the intermediate frequency useful signal by adopting a local real carrier wave to generate a baseband signal; Performing matched filtering on the baseband signal to maximize the output signal-to-noise ratio and eliminate intersymbol interference so as to obtain a bipolar baseband signal; and (4) recovering the bipolar baseband signal into a binary bit stream by adopting optimal timing sampling and threshold judgment to generate an output bit stream.
5. The BPSK signal processing method based on the circular antenna array and the adaptive beamforming according to claim 1, wherein the calculating the output signal-to-noise ratio of each antenna array by traversing the full space angle, calculating the signal-to-noise ratio gain, the pointing precision and the discrimination according to the beam response characteristics, analyzing the performance of each antenna array, determining the optimal array comprises: Calculating the output signal-to-noise ratio of each antenna array by traversing the full space angle; and according to the beam response characteristics, calculating the signal-to-noise ratio gain and the pointing precision, and selecting an antenna array with the maximum signal-to-noise ratio gain and the minimum pointing precision as an optimal array.
6. The BPSK signal processing method based on circular antenna array and adaptive beamforming according to claim 5, wherein said calculating an output signal-to-noise ratio of each antenna array by traversing a full spatial angle comprises: traversing the beam directions in the whole space, constructing a weighting vector for each direction, and respectively carrying out beam forming on the array signal matrix X and the noise matrix N to generate a beam signal And noise ; Calculating the downward output signal-to-noise ratio of each finger by adopting a power separation method, wherein the expression is as follows: In the formula, To output total power; To output noise power; for output signal to noise ratio.
7. The BPSK signal processing method based on the circular antenna array and the adaptive beamforming according to claim 1, wherein the generating a segmented dynamic input signal, calculating a variable steering vector of an optimal array, generating a segmented dynamic array signal matrix, comprises: dividing the time axis into equal parts, and generating dynamic input signals according to different incident angles; Grouping dynamic input signals, respectively generating each group of corresponding azimuth angle and pitch angle, and generating dynamic incident angle data; Generating a time-varying guide vector of the optimal array according to the dynamic incident angle data; and defining a time window according to the grouping length, extracting local data of the radio frequency signal and the noise matrix, generating a local array signal matrix by combining the time-varying steering vector, and combining all the local array signal matrices to obtain a dynamic array signal matrix.
8. The BPSK signal processing method based on the circular antenna array and the adaptive beamforming according to claim 1, wherein said weighting vectors based on the dynamic input signal and the dynamic array signal matrix, respectively, in real time, comprise: The weight vector of conventional beam forming is the corresponding steering vector of beam pointing, and the expression is: the maximum signal-to-noise ratio criterion is optimized for the maximum output signal-to-noise ratio, and the expression is: In the formula, For output signal to noise ratio; Is a weight vector; Is a noise matrix; Calculating for statistics expectation; Is the complex amplitude of the signal; is a radio frequency signal; output signal to noise ratio Taking the maximum value, the expression of the weight vector is: In the formula, A weight vector that is the maximum signal-to-noise criterion; Is a noise matrix Is a covariance of (2); Is minimum value, prevent covariance Zero; Is a unit matrix; is a dynamic guide vector; The minimum mean square error criterion, the optimization target is that the mean square error of the beam output and the expected reference signal is minimum, and the expression is: In the formula, Is a mean square error cost function; Calculating for statistics expectation; Is the desired reference signal; is a local dynamic array signal matrix; Order the Taking the minimum value, the weight vector expression of the minimum mean square error criterion is as follows: In the formula, A weight vector that is a minimum mean square error criterion; covariance matrix of dynamic input signal; as covariance matrix With the desired reference signal A cross-correlation matrix between; the linear constraint minimum variance criterion, the expression of the weight vector is: In the formula, Weight vector which is a linear constraint minimum variance criterion.
9. The BPSK signal processing method according to claim 1, wherein the beamforming is performed on the dynamic array signal matrix according to the weight vector of the respective adaptation criterion, the dynamic beam signal is generated, and the binary bit stream is recovered, and the dynamic output signal is generated, comprising: The expression for generating the dynamic beam signal is: In the formula, A dynamic beam signal that is an adaptive criterion in i; is the total number of time packets; Transpose the weight vector for the i-th criterion at the conjugate of the kth group; A local array signal matrix of a kth group; Is the time window length; And restoring the dynamic beam signals corresponding to the respective adaptation criteria into a binary bit stream to generate a dynamic output signal.

Description

BPSK signal processing method based on circular antenna array and adaptive beam forming Technical Field The invention relates to the technical field of array signal processing and digital communication simulation, in particular to a BPSK signal processing method based on a circular antenna array and self-adaptive beam forming. Background Array signal Processing (ARRAY SIGNAL Processing) is an important research branch in the field of electronic information, and has important application in the wide fields of information communication, radar detection, navigation positioning and the like. The method arranges a group of sensors such as antennas into an array according to a certain geometric relationship, receives signals from signal sources such as a space field on the basis of the array, and achieves the purposes of enhancing useful signals, resisting noise interference, reducing error rate, improving frequency band utilization rate and the like after processing the signals. Among them, digital beamforming (Digital Beamforming, DBF) is a core in the array signal processing. The input to the antenna array is typically from an analog or digital signal in space, so beamforming is also known as spatial filtering. The array signals are weighted and summed, and the gains are concentrated in the same direction, so that high gain and high precision in a specific direction or an optimal direction are realized, and further, complex applications such as information extraction, radar detection, navigation positioning and the like are realized. In the prior art, the workflow is usually focused on theoretical derivation and modular simulation verification of the beamforming algorithm itself, i.e. by proposing or improving an adaptive criterion (such as LCMV, MVDR) or optimization method (such as diagonal loading, robust design), and then verifying the performance of the algorithm in terms of pattern synthesis, interference suppression or convergence speed, etc. in a simulation environment, with ideal signals or typical signal models as inputs. However, the prior art has certain limitations, and has defects and blank in technical integration level, engineering guidance and system innovation: The technical integration level is to be improved, and a system-level solution is lacking, wherein the simulation of a single algorithm module is focused on in the prior art, and the system comprises a technical scheme for bringing a complete signal transmission link in the actual use environment such as communication signal modulation into a simulation verification and evaluation system, and a complete scheme for organically combining and co-simulating a plurality of technical layers such as array beam forming treatment, end-to-end performance evaluation and the like; The engineering guidance is relatively indirect, lacks a definite design path and quantization indexes, and aims at the application scene that the frequency is gradually improved and the real-time property is gradually important, the existing simulation technology relatively lacks a process of directly migrating to a design target and an evaluation standard on a definite and quantifiable system level performance index, and stays in algorithm design, comparison and verification, so that a clear engineering design path from algorithm performance to a system index in an actual engineering environment cannot be formed; In terms of integrity and system innovation, the algorithm on macroscopic view angle and depth fusion and optimization among all modules are lacking, most of single links focus on the design of the algorithm or a certain dimension of performance, and the like, the practical performance is estimated by combining all processes of a signal modulation-demodulation flow, an array configuration, a self-adaptive criterion and a beam forming algorithm, the system performance estimation on multiple dimensions on macroscopic view is lacking for depth fusion, the system level optimization of cross modules is realized on the whole level, the simple array gain is changed into the integral signal-to-noise ratio gain index considering all links, and the mutual influence among all links is relatively unfavorable to be considered, and a more global optimal system design scheme is obtained. Disclosure of Invention The invention aims to provide a BPSK signal processing method based on a circular antenna array and adaptive beam forming, which aims to solve or improve at least one of the technical problems. In order to achieve the above object, the present invention provides the following solutions: a BPSK signal processing method based on a circular antenna array and adaptive beamforming, comprising: generating a periodic BPSK baseband signal, adopting root raised cosine pulse shaping treatment, and performing up-conversion to radio frequency for two times to generate a radio frequency signal; Generating a noise matrix of the radio frequency signal by adopting Gaussian white nois