Method and device for estimating angle-of-arrival-polarization information of short-wave skywave signals

Abstract

The application relates to the technical field of short-wave radio, in particular to a short-wave sky wave signal angle-of-arrival-polarization information estimation method and device, wherein the method comprises the following steps: receiving a short-wave sky wave signal by using a preset short-wave three-component polarization receiving antenna array; based on a rank-deficient MUSIC algorithm and a multi-core parallel operation optimization strategy, performing corresponding array signal processing, signal source number estimation and multi-stage spectrum peak search operation in a preset DSP processor to obtain short-wave sky wave signal angle-of-arrival estimation information and polarization angle estimation information. According to the electromagnetic vector receiving antenna array and the DSP processing method, the sky wave signal angle-of-arrival and polarization information are estimated at the same time, so that the sky wave signal accurate direction finding, the signal quality improvement and the ionospheric wave propagation environment research are provided with the basis.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of short wave radio, and particularly relates to a method and device for estimating the angle-of-arrival-polarization information of a short wave sky wave signal. BACKGROUND

[0002] The short wave radio system has irreplaceable advantages such as low cost, long action distance, large service range and strong anti-destroying capability, and is widely applied in the fields of short wave broadcasting, short wave long-distance communication and high frequency sky wave over-the-horizon radar. The angle-of-arrival estimation of a short wave signal is helpful for the positioning of a transmitting station and a detected target, and has great application value in short wave radio management, electronic reconnaissance and emergency communication. Once the angle-of-arrival and polarization parameters of a short wave sky wave signal are known, the angle mismatch and polarization mismatch of a receiving end can be corrected through space domain or polarization domain filtering, ionospheric clutter can be suppressed, and the quality of a received signal can be improved. In addition, the ionospheric characteristics can be inversely researched by using the angle-of-arrival and polarization information of a signal.

[0003] However, when a short wave signal is transmitted in a sky wave propagation mode through ionospheric refraction, the angle-of-arrival and polarization information of the signal changes due to the complex time-space-frequency characteristics of the ionosphere, which affects the receiving performance of the signal and needs to be solved urgently. SUMMARY

[0004] The present application provides a method and device for estimating the angle-of-arrival-polarization information of a short wave sky wave signal, to solve the problems in the prior art that the angle-of-arrival and polarization information of a short wave signal easily changes during the transmission of the short wave signal in a sky wave propagation mode, which greatly affects the receiving performance of the short wave signal.

[0005] The first aspect embodiment of the present application provides a method for estimating the angle-of-arrival-polarization information of a short wave sky wave signal, comprising the following steps: receiving a short wave sky wave signal by using a preset short wave three-component polarization receiving antenna array; performing corresponding array signal processing, source number estimation and multi-level spectrum peak search operations in a preset DSP processor based on a rank-deficient MUSIC algorithm and a multi-core parallel operation optimization strategy, to obtain the angle-of-arrival estimation information and polarization angle estimation information of the short wave sky wave signal.

[0006] Optionally, in one embodiment of the present application, before performing the corresponding array signal processing, source number estimation and multi-level spectrum peak search operations in the preset DSP processor, the method further comprises the following steps: determining a target multi-core processor corresponding to the DSP processor and a target FPGA development board corresponding to a preset FPGA chip; performing preset signal processing on the short wave sky wave signal by using the FPGA chip, and transmitting the short wave sky wave signal processed by the signal processing from the target FPGA development board to the target multi-core processor carrying a SYS / BIOS operating system through an SRIO data interface.

[0007] Optionally, in an embodiment of the present application, the rank-deficient MUSIC algorithm comprises: sampling the short-wave skywave signal by using the short-wave three-component polarization receiving antenna array to obtain at least one snapshot sample point; generating an array output signal according to the at least one snapshot sample point, and calculating a maximum likelihood estimate of a self-covariance matrix of the array output signal; based on the maximum likelihood estimate, performing eigenvalue decomposition on the self-covariance matrix of the array output signal to obtain a plurality of eigenvalues; sorting the plurality of eigenvalues to generate a signal subspace and a noise subspace, and storing a matrix value of the noise subspace in a preset shared memory; determining a first level spectral peak search range, a first level search step value, a second level spectral peak search range and a second level search step value corresponding to a multi-level spectral peak search operation; based on the first level spectral peak search range, the first level search step value, the second level spectral peak search range and the second level search step value, and in combination with a preset spectral density algorithm, performing a multi-level spectral peak search operation to obtain the angle-of-arrival-polarization estimation information, wherein the angle-of-arrival estimation information and the polarization angle estimation information include an azimuth angle estimation value, an elevation angle estimation value, a polarization auxiliary angle estimation value and a polarization phase angle estimation value.

[0008] Optionally, in an embodiment of the present application, the performing corresponding array signal processing, source number estimation and multi-stage spectrum peak search operation in a preset DSP processor to obtain the angle of arrival estimation information and the polarization angle estimation information of the short-wave skywave signal comprises: performing first-stage spectrum peak search operation in the first-stage spectrum peak search range based on the first-stage search step to obtain position information and amplitude information of all spectrum peaks in the first-stage spectrum peak search range; sorting all the spectrum peaks in descending order according to the amplitude information to obtain a first-stage sorting result, and obtaining position information corresponding to the first K spectrum peaks of the first-stage sorting result to obtain a first-stage spectrum peak search result of the short-wave skywave signal through the position information corresponding to the first K spectrum peaks; judging whether the first-stage spectrum peak search result meets a preset accuracy requirement, wherein if the first-stage spectrum peak search result meets the preset accuracy requirement, the first-stage spectrum peak search operation is ended, the angle of arrival estimation information is generated, and polarization angle estimation operation is performed according to the angle of arrival estimation information to obtain polarization angle estimation information, wherein K is a positive integer; if the first-stage spectrum peak search result does not meet the preset accuracy requirement, second-stage spectrum peak search operation is performed in the second-stage spectrum peak search range according to the second-stage search step to obtain all spectrum peaks in the second-stage spectrum peak search range, and all the spectrum peaks in the second-stage spectrum peak search range are sorted in descending order to obtain a second-stage sorting result, and the angle of arrival information corresponding to the first K spectrum peaks of the second-stage sorting result is obtained; judging whether the angle of arrival information meets the preset accuracy requirement, wherein if the preset accuracy requirement is not met, the second-stage spectrum peak search operation is repeatedly performed, otherwise the second-stage spectrum peak search operation is ended, and the angle of arrival estimation information and the polarization angle estimation information are obtained.

[0009] Optionally, in one embodiment of this application, the multi-core parallel computing optimization strategy includes: determining multiple overlapping interval thresholds corresponding to the first-level spectral peak search range, and dividing the first-level spectral peak search range into multiple search intervals on an average basis according to the multiple overlapping interval thresholds; performing a first-level spectral peak search operation through the multiple search intervals and the target multi-core processor to obtain the maximum spectral peak of the main core and each slave core in the target multi-core processor and the azimuth and elevation angles corresponding to the maximum spectral peaks; sending the maximum spectral peaks of each slave core and the azimuth and elevation angles corresponding to the maximum spectral peaks to the main core, so that the main core can perform the first-level spectral peak search operation according to the multiple search intervals and the target multi-core processor. The true spectral peak is obtained from the azimuth and elevation angles corresponding to the maximum spectral peak of the core; the angle of arrival corresponding to the true spectral peak is determined based on the azimuth and elevation angles, and it is determined whether the angle of arrival meets the preset range requirement; if the angle of arrival meets the preset range requirement, the second-level spectral peak search operation is performed according to the second-level search step value, and the matrix value of the noise subspace in the shared memory is called by the target multi-core processor, so that the target multi-core processor performs parallel operation based on the matrix value of the noise subspace and the preset spectral density algorithm to obtain the angle of arrival estimation information and the polarization angle estimation information.

[0010] Optionally, in one embodiment of this application, the mathematical expression of the preset spectral density algorithm is:

[0011]

[0012] Where, θ k This represents the azimuth angle of the k-th shortwave skywave signal; γ represents the elevation angle of the k-th shortwave skywave signal; k η represents the polarization auxiliary angle of the k-th shortwave skywave signal; k This represents the polarization phase angle of the k-th shortwave skywave signal; The array's steering vector is represented by h(γ, η); the polarization steering vector is represented by U. N Represents the noise subspace; H represents the conjugate transpose of the noise subspace; H represents the conjugate transpose.

[0013] A second aspect of this application provides an apparatus for estimating the angle of arrival and polarization information of a shortwave skywave signal, comprising: a receiving module for receiving a shortwave skywave signal using a preset shortwave three-component polarized receiving antenna array; and an estimation module for performing corresponding array signal processing, source number estimation, and multi-level spectral peak search operations in a preset DSP processor based on a rank-deficient MUSIC algorithm and a multi-core parallel computing optimization strategy to obtain the angle of arrival estimation information and polarization angle estimation information of the shortwave skywave signal.

[0014] Optionally, in one embodiment of the present application, further comprising: a setting module, configured to determine a target multi-core processor corresponding to the DSP processor and a target FPGA development board corresponding to the preset FPGA chip before performing corresponding array signal processing, source number estimation and multi-level spectrum peak search operation in the preset DSP processor; and a processing module, configured to perform preset signal processing on the short-wave skywave signal through the FPGA chip, and transmit the short-wave skywave signal processed by the FPGA chip to the target multi-core processor carrying a SYS / BIOS operating system through an SRIO data interface.

[0015] Optionally, in one embodiment of the present application, the estimation module comprises: a sampling unit, configured to sample the short-wave skywave signal by using the short-wave three-component polarization receiving antenna array to obtain at least one snapshot sample point; a calculation unit, configured to generate an array output signal according to the at least one snapshot sample point, and calculate a maximum likelihood estimate of a self-covariance matrix of the array output signal; a decomposition unit, configured to perform eigenvalue decomposition on the self-covariance matrix of the array output signal based on the maximum likelihood estimate to obtain a plurality of eigenvalues; a storage unit, configured to sort the plurality of eigenvalues to generate a signal subspace and a noise subspace, and store a matrix value of the noise subspace in a preset shared memory; a first determination unit, configured to determine a first-level spectrum peak search range, a first-level search step value, a second-level spectrum peak search range and a second-level search step value corresponding to a multi-level spectrum peak search operation; a search unit, configured to perform the multi-level spectrum peak search operation based on the first-level spectrum peak search range, the first-level search step value, the second-level spectrum peak search range and the second-level search step value, and in combination with a preset spectrum density algorithm to obtain the angle-of-arrival-polarization estimation information, wherein the angle-of-arrival estimation information and the polarization angle estimation information comprise an azimuth angle estimation value, an elevation angle estimation value, a polarization auxiliary angle estimation value and a polarization phase angle estimation value.

[0016] Optionally, in an embodiment of the present application, the estimation module further comprises: an acquisition unit, configured to perform a first-level spectrum peak search operation in the first-level spectrum peak search range based on the first-level search step value, to acquire position information and amplitude information of all spectrum peaks in the first-level spectrum peak search range; a first sorting unit, configured to sort the all spectrum peaks in descending order according to the amplitude information, to obtain a first-level sorting result, and acquire position information corresponding to the first K spectrum peaks of the first-level sorting result, so as to obtain the first-level spectrum peak search result of the short-wave sky wave signal through the position information corresponding to the first K spectrum peaks; a first judgment unit, configured to judge whether the first-level spectrum peak search result meets a preset accuracy requirement, wherein if the first-level spectrum peak search result meets the preset accuracy requirement, the first-level spectrum peak search operation is ended, the arrival angle estimation information is generated, and a polarization angle estimation operation is performed according to the arrival angle estimation information to obtain polarization angle estimation information, wherein K is a positive integer; a second sorting unit, configured to, if the first-level spectrum peak search result does not meet the preset accuracy requirement, perform a second-level spectrum peak search operation in the second-level spectrum peak search range according to the second-level search step value, to obtain all spectrum peaks in the second-level spectrum peak search region, and sort the all spectrum peaks in the second-level spectrum peak search region in descending order to obtain a second-level sorting result, and acquire arrival angle information corresponding to the first K spectrum peaks of the second-level sorting result; and a second judgment unit, configured to judge whether the arrival angle information meets the preset accuracy requirement, wherein if the preset accuracy requirement is not met, the second-level spectrum peak search operation is repeatedly performed, otherwise the second-level spectrum peak search operation is ended, and the arrival angle estimation information and the polarization angle estimation information are obtained.

[0017] Optionally, in an embodiment of the present application, the estimation module further comprises: a second determination unit configured to determine a plurality of overlapping interval threshold values corresponding to the first level spectrum peak search range, and divide the first level spectrum peak search range into a plurality of search intervals according to the plurality of overlapping interval threshold values; an execution unit configured to perform a first level spectrum peak search operation through the plurality of search intervals and the target multi-core processor to obtain a maximum spectrum peak of a master core and each slave core in the target multi-core processor and an azimuth angle and an elevation angle corresponding to the maximum spectrum peak; a sending unit configured to send the maximum spectrum peak of each slave core and the azimuth angle and the elevation angle corresponding to the maximum spectrum peak to the master core, so as to obtain a real spectrum peak according to the azimuth angle and the elevation angle corresponding to the maximum spectrum peak of each slave core through the master core; a third determination unit configured to determine an angle of arrival corresponding to the real spectrum peak according to the azimuth angle and the elevation angle corresponding to the real spectrum peak, and determine whether the angle of arrival meets a preset range requirement; and a calling unit configured to, if the angle of arrival meets the preset range requirement, perform a second level spectrum peak search operation according to the second level search step value, and call a matrix value of the noise subspace in the shared memory through the target multi-core processor, so that the target multi-core processor performs parallel operation according to the matrix value of the noise subspace and the preset spectrum density algorithm to obtain the angle of arrival estimation information and the polarization angle estimation information.

[0018] Optionally, in an embodiment of the present application, a mathematical expression of the preset spectrum density algorithm is as follows:

[0019]

[0020] wherein θ k represents the azimuth angle of the kth short-wave skywave signal; k wherein θ k represents the azimuth angle of the kth short-wave skywave signal; wherein θ k represents the azimuth angle of the kth short-wave skywave signal; k wherein γ k represents the polarization auxiliary angle of the kth short-wave skywave signal; k wherein γ k represents the polarization auxiliary angle of the kth short-wave skywave signal; wherein h(γ,η) represents the polarization steering vector; U represents the steering vector of the array; N wherein H represents the conjugate transpose of the noise subspace; wherein H represents the conjugate transpose of the noise subspace;

[0021] A third aspect embodiment of the present application provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and capable of running on the processor, and the processor executes the program to implement the short-wave skywave signal angle of arrival-polarization information estimation method as described in the above embodiments.

[0022] The fourth aspect of the embodiment of the present application provides a computer readable storage medium storing a computer program, which is executed by a processor to implement the short-wave sky-wave signal angle-of-arrival-polarization information estimation method.

[0023] The fifth aspect of the embodiment of the present application provides a computer program product including a computer program, which is executed to implement the short-wave sky-wave signal angle-of-arrival-polarization information estimation method.

[0024] Therefore, the embodiment of the present application has the following beneficial effects:

[0025] The embodiment of the present application can utilize a preset short-wave three-component polarization receiving antenna array to receive a short-wave sky-wave signal, perform corresponding array signal processing, source number estimation and multi-stage spectrum peak search operation in a preset DSP processor based on a rank-deficient MUSIC algorithm and a multi-core parallel operation optimization strategy, and obtain angle-of-arrival estimation information and polarization angle estimation information of the short-wave sky-wave signal. The present application estimates the angle-of-arrival and polarization information of the sky-wave signal simultaneously according to the electromagnetic vector receiving antenna array and the DSP processing method, thereby providing a basis for accurate direction finding of the sky-wave signal, improving the signal quality and ionospheric wave propagation environment research. Therefore, the problems such as the angle-of-arrival and polarization information of the short-wave signal being easily changed during the transmission of the short-wave signal in the sky-wave propagation mode in the prior art, which greatly affects the reception performance of the short-wave signal, are solved.

[0026] Additional aspects and advantages of the present application will be made apparent by the following description and the accompanying drawings. BRIEF DESCRIPTION OF DRAWINGS

[0027] The above and / or additional aspects and advantages of the present application will become apparent and be readily understood from the following description, taken in conjunction with the accompanying drawings, in which:

[0028] Figure 1 A flowchart of a short-wave sky-wave signal angle-of-arrival-polarization information estimation method according to an embodiment of the present application is provided.

[0029] Figure 2 A composition framework schematic diagram of a short-wave sky-wave multi-channel electromagnetic vector receiving system according to an embodiment of the present application is provided.

[0030] Figure 3 A signal angle-of-arrival-polarization two-stage spectrum peak search flowchart according to an embodiment of the present application is provided.

[0031] Figure 4 An 8-core two-dimensional angle-of-arrival search range diagram according to an embodiment of the present application is provided.

[0032] Figure 5 A data flow mode topology diagram provided for an embodiment of the present application;

[0033] Figure 6 An SRIO (Serial RapidIO) interrupt control flow diagram provided for an embodiment of the present application;

[0034] Figure 7 A DSP (Digital Signal Processing) algorithm implementation overall process diagram provided for an embodiment of the present application;

[0035] Figure 8 A horizontal polarization dipole uniform circular array diagram provided for an embodiment of the present application;

[0036] Figure 9 An example diagram of a short-wave sky wave signal angle-of-arrival-polarization information estimation device according to an embodiment of the present application;

[0037] Figure 10 A structure diagram of an electronic device provided for an embodiment of the present application.

[0038] Among them, 10 is a short-wave sky wave signal angle-of-arrival-polarization information estimation device; 100 is a receiving module, 200 is an estimation module; 1001 is a memory, 1002 is a processor, and 1003 is a communication interface. DETAILED DESCRIPTION

[0039] The embodiments of the present application are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar notations represent the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the accompanying drawings are exemplary and are intended to explain the present application, and cannot be understood as a limitation of the present application.

[0040] The method and device for estimating the angle-of-arrival-polarization information of a short-wave sky wave signal according to the embodiments of the present application are described below with reference to the accompanying drawings. In view of the problems mentioned in the background, the present application provides a method for estimating the angle-of-arrival-polarization information of a short-wave sky wave signal. In the method, a preset short-wave three-component polarization receiving antenna array is used to receive a short-wave sky wave signal. Based on a rank-deficient MUSIC (Multiple Signal Classification) algorithm and a multi-core parallel operation optimization strategy, corresponding array signal processing, source number estimation, and multi-level spectrum peak search operations are performed in a preset DSP processor to obtain the angle-of-arrival estimation information and the polarization angle estimation information of the short-wave sky wave signal. According to the electromagnetic vector receiving antenna array and the DSP processing method, the present application simultaneously estimates the angle-of-arrival and polarization information of the sky wave signal, thereby providing a basis for accurate direction finding of the sky wave signal, improving the signal quality, and studying the ionospheric wave propagation environment. Thus, the problems in the prior art, such as the change of the angle-of-arrival and polarization information of the short-wave signal during the transmission of the short-wave signal in the sky wave propagation mode, which greatly affects the reception performance of the short-wave signal, are solved.

[0041] Specifically, Figure 1 A flowchart of the method for estimating the angle-of-arrival-polarization information of a short-wave sky wave signal according to the embodiments of the present application is shown in FIG. 1.

[0042] As shown in FIG. 1, the method for estimating the angle-of-arrival-polarization information of a short-wave sky wave signal includes the following steps: Figure 1

[0043] In step S101, a preset short-wave three-component polarization receiving antenna array is used to receive a short-wave sky wave signal.

[0044] In step S102, based on a rank-deficient MUSIC algorithm and a multi-core parallel operation optimization strategy, corresponding array signal processing, source number estimation, and multi-level spectrum peak search operations are performed in a preset DSP processor to obtain the angle-of-arrival estimation information and the polarization angle estimation information of the short-wave sky wave signal.

[0045] Optionally, in an embodiment of the present application, before the corresponding array signal processing, source number estimation, and multi-level spectrum peak search operations are performed in the preset DSP processor, the method further includes: determining a target multi-core processor corresponding to the DSP processor and a target FPGA development board corresponding to a preset FPGA (Field Programmable Gata Array) chip; performing preset signal processing on the short-wave sky wave signal through the FPGA chip, and transmitting the signal-processed short-wave sky wave signal from the target FPGA development board to the target multi-core processor carrying a SYS / BIOS operating system through an SRIO data interface.

[0046] ​The embodiment of the present application can first select a suitable DSP processor and FPGA according to the composition framework, characteristics and implementation target of the short-wave skywave multi-channel electromagnetic vector receiving system; then receive short-wave skywave signals through a short-wave three-component polarization receiving antenna array and solve the short-wave skywave signals in the DSP processor to obtain the angle-of-arrival-polarization estimation information.

[0047] It should be noted that the short-wave skywave multi-channel electromagnetic vector receiving system is composed of an electromagnetic vector receiving antenna array, a multi-channel radio frequency (RF) receiver, a multi-channel analog-to-digital conversion module (A / D) and a DSP information processing module (i.e., a DSP processor).

[0048] The electromagnetic vector receiving antenna array can be a uniform circular array composed of dipole antenna elements or an L-shaped receiving antenna array or a two-dimensional coprime array composed of orthogonal three-component receiving elements; the DSP signal processing module adopts a high-performance multi-core processor TMS320XXX development board (i.e., a target multi-core processor) and utilizes the working mode of FPGA plus DSP, and the FPGA in the embodiment of the present application can adopt the development board XC7KYYY (i.e., a target FPGA development board) of the Xilinx Kintex-7 series; the FPGA is suitable for processing high-speed data and repetitive tasks, and thus can be used for radio frequency front-end filtering processing, baseband frequency conversion, multi-channel acquisition and the like, and sends data to the DSP processor for processing through a high-speed SRIO data interface; the DSP processor is suitable for processing complex processing tasks of low-rate data due to its fast operation speed, and can be used for array signal processing to realize estimation of signal angle-of-arrival and polarization information.

[0049] As an implementable mode, the core board of the embodiment of the present application contains DSP and FPGA chips, and can transmit data and interact information with the FPGA through an SRIO channel; the JTAG debugging port of the FPGA and the DSP can be used to debug the algorithm on the development board through an emulator; the TMS320XXX development board in the embodiment of the present application can use the SYS / BIOS operating system to receive data from the FPGA, and adopts a rank-deficient MUSIC algorithm as an angle-of-arrival and polarization information estimation algorithm; the DSP hardware implementation of the angle-of-arrival and polarization information estimation algorithm mainly includes multi-level spectrum peak search and multi-core parallel operation optimization strategy, thereby realizing hardware fast implementation of the angle-of-arrival and polarization information estimation algorithm.

[0050] Optionally, in an embodiment of the present application, the rank-deficient MUSIC algorithm comprises: sampling a short-wave three-component polarization receiving antenna array on a short-wave sky wave signal to obtain at least one snapshot sample point; generating an array output signal according to the at least one snapshot sample point, and calculating a maximum likelihood estimate of a self-covariance matrix of the array output signal; based on the maximum likelihood estimate, performing eigenvalue decomposition on the self-covariance matrix of the array output signal to obtain a plurality of eigenvalues; sorting the plurality of eigenvalues to generate a signal subspace and a noise subspace, and storing a matrix value of the noise subspace in a preset shared memory; determining a first level spectral peak search range, a first level search step value, a second level spectral peak search range, and a second level search step value corresponding to a multi-level spectral peak search operation; based on the first level spectral peak search range, the first level search step value, the second level spectral peak search range, and the second level search step value, and in combination with a preset spectral density algorithm, performing the multi-level spectral peak search operation to obtain angle-of-arrival-polarization estimation information, wherein the angle-of-arrival estimation information and the polarization angle estimation information include an azimuth angle estimation value, an elevation angle estimation value, a polarization auxiliary angle estimation value, and a polarization phase angle estimation value.

[0051] It should be noted that the key steps of the vector array multiple signal classification algorithm (MUSIC) in the embodiments of the present application are as follows:

[0052] 1. Sampling a short-wave three-component polarization receiving antenna array on a received signal (i.e., a short-wave sky wave signal) to obtain at least one snapshot sample point, and obtaining an array output signal according to the snapshot sample point, and then solving a maximum likelihood estimate of a self-covariance matrix thereof;

[0053] 2. Performing eigenvalue decomposition on the covariance matrix of the array output signal to obtain a plurality of eigenvalues, and arranging the plurality of eigenvalues to obtain a signal subspace and a noise subspace;

[0054] 3. Setting appropriate search ranges (i.e., a first level spectral peak search range and a second level spectral peak search range corresponding to a multi-level spectral peak search operation) and search step lengths (i.e., a first level search step value and a second level search step value corresponding to the multi-level spectral peak search operation), and performing the multi-level spectral peak search operation to obtain an azimuth angle θ and an elevation angle

[0055] 4. According to the azimuth angle θ, the elevation angle of the short-wave sky wave signal, and the amplitude of the signal, obtaining a polarization auxiliary angle γ and a polarization phase angle η of the short-wave sky wave signal.

[0056] Therefore, the embodiments of the present application realize the spectrum peak search of the sky wave signal angle of arrival and polarization information by using the rank-deficient multiple signal classification algorithm including the operations of matrix multiplication, eigenvalue decomposition, ordering, matrix eigenvalue decomposition (including QR decomposition method, LU decomposition method, etc.), so as to complete the estimation of the signal angle of arrival and polarization auxiliary angle and polarization phase angle in the DSP.

[0057] Optionally, in an embodiment of the present application, the mathematical expression of the preset spectrum density algorithm is as follows:

[0058]

[0059] Wherein, θ k represents the azimuth angle of the kth short wave sky wave signal; represents the elevation angle of the kth short wave sky wave signal; γ k represents the polarization auxiliary angle of the kth short wave sky wave signal; η k represents the polarization phase angle of the kth short wave sky wave signal; represents the steering vector of the array; h (γ, η) represents the polarization steering vector; U N represents the noise subspace; represents the conjugate transpose of the noise subspace; H represents the conjugate transpose.

[0060] In the specific implementation process, the kth short wave sky wave signal angle of arrival of the multiple signal classification algorithm based on the vector array in the embodiments of the present application is as follows: and the spectrum density algorithm of the polarization auxiliary angle and the polarization phase angle (γ k , η k ) is as follows:

[0061]

[0062] From the above formula, it can be obtained that: Wherein, U N represents the autocorrelation function R XX =E[XX H ], the noise subspace obtained by performing eigenvalue decomposition, XX is the signal received by the vector receiving antenna array, and

[0063]

[0064] Let n be the antenna number, is the position of the antenna, and α and β are the included angles of the projection of the antenna with the positive direction of the x axis and the z axis respectively, so the following formula can be obtained:

[0065]

[0066] and

[0067]

[0068] e m = [sinβ m cosα m , sinβ m sinα m , cosβ m , 0, 0, 0]

[0069]

[0070] It should be noted that h (γ, η) is the solution of the following formula as There must be a non-zero case:

[0071]

[0072] After obtaining the intensity of the signal The relationship between the polarization auxiliary angle and the polarization phase angle (γ, η) and the intensity of the signal is:

[0073]

[0074] When the MUSIC algorithm is performed, the number of signal sources is estimated, and the AIC criterion or the MDL criterion or the HQ criterion based on information theory can be used.

[0075] Optionally, in an embodiment of the present application, the corresponding array signal processing, source number estimation and multi-stage spectrum peak search operation are performed in a preset DSP processor to obtain the angle of arrival estimation information and the polarization angle estimation information of the short-wave skywave signal, comprising: performing a first-stage spectrum peak search operation in a first-stage spectrum peak search range based on a first-stage search step value to obtain the position information and the amplitude information of all spectrum peaks in the first-stage spectrum peak search range; sorting all spectrum peaks in descending order according to the amplitude information to obtain a first-stage sorting result, and obtaining the position information corresponding to the first K spectrum peaks of the first-stage sorting result to obtain a first-stage spectrum peak search result of the short-wave skywave signal through the position information corresponding to the first K spectrum peaks; judging whether the first-stage spectrum peak search result meets a preset accuracy requirement, wherein if the first-stage spectrum peak search result meets the preset accuracy requirement, the first-stage spectrum peak search operation is ended, and the angle of arrival estimation information is generated, and a polarization angle estimation operation is performed according to the angle of arrival estimation information to obtain the polarization angle estimation information, wherein K is a positive integer; if the first-stage spectrum peak search result does not meet the preset accuracy requirement, a second-stage spectrum peak search operation is performed in a second-stage spectrum peak search range according to a second-stage search step value to obtain all spectrum peaks in a second-stage spectrum peak search region, and all spectrum peaks in the second-stage spectrum peak search region are sorted in descending order to obtain a second-stage sorting result, and the angle of arrival information corresponding to the first K spectrum peaks of the second-stage sorting result is obtained; judging whether the angle of arrival information meets the preset accuracy requirement, wherein if the preset accuracy requirement is not met, the second-stage spectrum peak search operation is repeatedly performed, otherwise the second-stage spectrum peak search operation is ended, and the angle of arrival estimation information and the polarization angle estimation information are obtained.

[0076] In an embodiment of the present application, the specific steps of the multi-stage spectrum peak search operation are as follows:

[0077] Step 1: Set the pitch angle θ and the azimuth angle The step value (i.e. the first-stage search step value) for performing the coarse-precision search (i.e. the first-stage spectrum peak search operation) is searched in the search range of the two-dimensional angle of arrival (i.e. the first-stage spectrum peak search range), and the positions and amplitudes of all spectrum peaks appearing are recorded;

[0078] Step 2: Sort all peak values in descending order of amplitude, and take the positions corresponding to the first K (K is the number of sources obtained through source number estimation) maximum values to obtain the first-stage spectrum peak search result corresponding to the azimuth angle and the pitch angle; if the first-stage spectrum peak search result meets the accuracy requirement, the first-stage spectrum peak search operation is ended, and the estimation result of the angle of arrival is obtained, and the polarization angle is estimated according to the result; if the first-stage spectrum peak search result does not meet the accuracy requirement, the second-stage spectrum peak search operation of Step 3 is performed;

[0079] Step 3: In a certain range (i.e., the second spectrum peak search range) near the peak obtained in step 2, a smaller step value (i.e., the second search step value) of the fine search is selected, and all the appearing peaks are recorded and sorted, the maximum K peaks are selected, and the corresponding angle of arrival information is obtained. The accuracy of the angle of arrival information is judged. If the accuracy of the angle of arrival information meets the preset accuracy requirement, the second spectrum peak search operation of the angle of arrival is stopped, and the polarization information estimation is performed, so as to obtain the angle of arrival estimation information and the polarization angle estimation information. Otherwise, step 3 is repeated.

[0080] Therefore, the embodiment of the present application first performs a wide range search to determine a search interval, and then performs a two-stage peak search to perform a fine search operation in a small interval, thereby realizing fast and accurate estimation of the angle of arrival-polarization of the short-wave skywave propagation signal.

[0081] Optionally, in an embodiment of the present application, the multi-core parallel operation optimization strategy includes: determining a plurality of overlapping interval critical values corresponding to the first spectrum peak search range, and dividing the first spectrum peak search range into a plurality of search intervals according to the plurality of overlapping interval critical values; performing the first spectrum peak search operation through the plurality of search intervals and the target multi-core processor to obtain the maximum spectrum peak and the azimuth and elevation angles corresponding to the maximum spectrum peak of the master core and each slave core in the multi-core processor; sending the maximum spectrum peak and the azimuth and elevation angles corresponding to the maximum spectrum peak of each slave core to the master core, so as to obtain the real spectrum peak according to the azimuth and elevation angles corresponding to the maximum spectrum peak of each slave core through the master core; determining the angle of arrival corresponding to the real spectrum peak according to the azimuth and elevation angles corresponding to the real spectrum peak, and judging whether the angle of arrival meets the preset range requirement; if the angle of arrival meets the preset range requirement, performing the second spectrum peak search operation according to the second search step value, and calling the matrix value of the noise subspace in the shared memory through the target multi-core processor, so that the target multi-core processor performs parallel operation according to the matrix value of the noise subspace and the preset spectrum density algorithm to obtain the angle of arrival estimation information and the polarization angle estimation information.

[0082] It should be noted that in the multi-core parallel operation optimization strategy of the embodiment of the present application, the topology structure between the cores can adopt a master-slave mode and a data flow mode, wherein in the master-slave mode, one of the multi-cores can be selected as the master core, and the others are slave cores, and in the data flow mode, each core depends on the processing result of the previous core.

[0083] In the actual execution process, in order to avoid the transformation of the peak value at the critical value of the multiple interval ranges, the embodiment of the present application can make the critical values of the adjacent intervals have a certain overlap when partitioning, that is, the multi-cores perform the first spectrum peak search operation to search different angle ranges to improve the spectrum peak search speed, wherein the total value range of the azimuth angle is θ∈[0°~360°], and the total value range of the elevation angle is

[0084] Furthermore, embodiments of this application can divide the search range of the azimuth angle into multiple intervals (i.e., multiple search intervals) to perform angle search within multiple cores, and place the noise subspace matrix value in shared memory for simultaneous access by each core, distributing the computation to eight cores for parallel processing to reduce computation time and improve real-time performance while ensuring a certain level of accuracy and correctness, thereby avoiding repeated computations.

[0085] As one possible approach, in an embodiment of this application, the overall range of azimuth angle is θ∈[0°~360°]. Based on the principle of the half-interval search method, a search is performed within the range of θ∈[0°~180°], and the elevation angle is... After the multi-core processor completes the first-level spectral peak search, the slave cores of the multi-core processor (e.g., seven slave cores) will each set their maximum value and corresponding θ. The values ​​are sent to the main kernel (e.g., kernel 0), where the main kernel compares and selects the θ values ​​corresponding to the K largest peak values. It then determines whether the peak is real or spurious, and performs a second peak search with a smaller step value and estimates the polarization angle within ±1° of the arrival angle corresponding to the real peak.

[0086] It should be noted that after the azimuth search angle range for each core in a multi-core processor is defined, each θ is used... corresponding The invariant property is that each core stores it so that it does not need to be re-evaluated during the next parameter estimation. The operation is directly called and multiplied with the noise covariance to calculate the spectral density within the search range, thereby speeding up the operation.

[0087] It is understood that the embodiments of this application can, based on the characteristics of TMS320XXX, and through the DSP processor, utilize modules such as multi-core communication, shared memory, multi-task threads, and semaphores to establish a structure for efficient communication between multiple cores, quickly transmitting data and notification information such as angle of arrival estimation results, noise subspace addresses, and notifications to each core to run or suspend waiting between cores; it should be noted that when the DSP processor performs floating-point operations, it can use the cmd file to constrain the location to customize the storage location of variables in the operation, so as to dynamically and flexibly allocate and release the operation space of the array in the operation.

[0088] Therefore, the embodiments of this application enable multiple cores of the TMS320XXX to perform spectral peak search simultaneously, realize multi-level spectral peak search and multi-core parallel operation in the DSP processor, and further reduce the amount of computation by using the multi-level search method to improve the search speed.

[0089] The execution process of the short-wave sky wave signal angle-of-arrival-polarization information estimation method of the application is described in detail below by taking a horizontal polarization dipole uniform circular array as an example, through a specific embodiment and in combination with the drawings.

[0090] In specific embodiments of the application, as shown in Figure 2 The execution logic architecture of the short-wave sky wave signal angle-of-arrival-polarization estimation method of the application mainly includes a vector array antenna receiving module, a multi-channel analog receiver module, a multi-channel signal acquisition module, and a DSP signal processing module.

[0091] As shown in Figure 3 The horizontal polarization dipole uniform circular array converts the received short-wave sky wave signal into energy, converting spatial short-wave sky wave electromagnetic waves into high-frequency current;

[0092] The multi-channel analog receiver module converts the signals converted by the vector receiving antenna from radio frequency signals into intermediate frequency signals, and improves the reception quality of the signals through power amplification, filtering, and other operations in the process;

[0093] The multi-channel signal acquisition module converts the analog signals into digital signals by sampling and analog-to-digital converting the multi-channel complex baseband signals, so as to process them by the DSP processor. In the hardware implementation of information processing, the working mode of FPGA plus DSP is adopted, the FPGA is responsible for radio frequency front-end filtering processing, baseband frequency conversion, multi-channel acquisition, etc., and the DSP is mainly responsible for signal processing, and is the key and critical part of the entire system.

[0094] In specific embodiments of the application, the hardware implementation of signal angle-of-arrival estimation mainly includes multi-stage spectrum peak search, multi-core parallel operation, half-interval search method of horizontal polarization dipole uniform circular array, etc., as shown in Figure 4 .

[0095] Among them, the multi-stage spectrum peak search first performs a wide-range search to determine a search interval, and then performs a secondary peak search for fine search in a small interval; the multi-core parallel operation is to search different angle ranges at the same time when performing the first-stage peak search by 8 cores, so as to improve the spectrum peak search speed; the half-interval search method searches in half of the interval through the constructed new spectrum peak function and search steps.

[0096] As understood by those skilled in the art, the multi-stage spectrum peak search gradually reduces the step value and search range at each stage until the accuracy requirement is met, thereby avoiding many redundant operations. Specifically, the steps of the multi-stage spectrum peak search are as follows:

[0097] Step 1: Set the step value for azimuth angle and elevation angle for coarse-precision search, search in the search range of two-dimensional angle-of-arrival, and record the position and amplitude of all spectrum peaks appearing;

[0098] Step 2: Sort all peaks by amplitude from high to low, take the first K (K is the number of sources estimated by the source) maximum value corresponding position, get the corresponding azimuth and elevation angle as the first level spectrum peak search result; if the result meets the accuracy requirement, end the spectrum peak search, get the estimation result of the angle of arrival and estimate the polarization angle according to the result, if the result does not meet the accuracy requirement, perform the second level search operation;

[0099] Step 3: In a certain range near the peak value obtained in step 2, select a smaller step value for fine search, continue to record all the appearing peaks and sort them, select the maximum K peaks and obtain the angle of arrival information corresponding to the peaks, judge the accuracy of the angle of arrival information, if it meets the accuracy requirement, stop the spectrum peak search operation of the angle of arrival, and estimate the polarization information, otherwise, repeat step 3.

[0100] It should be noted that when performing multi-level spectrum peak search operation, since the calculation of each angle spectrum density is independent, and the calculation result of the noise subspace self-covariance is the same, the search range of the azimuth angle can be evenly divided into eight intervals and the angle search is performed in eight cores, and the noise subspace matrix value is placed in the shared memory and called by each core, avoiding repeated operation, and the operation is distributed to eight cores for parallel processing, reducing the running time, and under the condition of ensuring a certain accuracy and correctness, the real-time performance of the operation is effectively improved; at the same time, in order to avoid the transformation of the peak value at the critical value of the eight interval range, the specific embodiment of the application can make the critical value of the adjacent intervals have a certain overlap when partitioning.

[0101] In the specific embodiment of the application, the overall value range of the azimuth angle is θ∈[0°~360°], according to the principle of half-interval search method, search in the range of θ∈[0°~180°], as shown in Table 1, the elevation angle is After the eight cores complete the first level spectrum peak search, seven slave cores send the maximum value and the corresponding θ, value of each core to core 0 for comparison and selection of the K maximum peak value corresponding to θ, and then judge whether it is a real spectrum peak or a false spectrum peak, and then perform a second spectrum peak search with a smaller step value and polarization angle estimation in the range of ±1° of the angle of arrival corresponding to the real spectrum peak; when the angle range of the azimuth angle searched by each core is determined, the corresponding to each θ, is constant, and each core can store it, so that the next parameter estimation does not have to perform The operation of the noise covariance matrix is directly called and multiplied by the noise covariance matrix to calculate the spectrum density in the search range, so as to speed up the operation to a certain extent, and also occupy a certain storage space.

[0102] Table 1

[0103]

[0104] In order to better realize the multi-stage spectrum peak search and multi-core parallel operation in hardware, the present application can establish a structure with simple logic, easy implementation and efficient communication between cores according to the characteristics of TMS320XXX, quickly transmit the angle of arrival estimation result, noise subspace address, and other data and notification information such as notifying each core to run or suspending waiting between cores. Since TMS320XXX uses SYS / BIOS operating system to modularize the algorithm, the SYS / BIOS operating system can be used to divide the complex task into multiple tasks and perform task scheduling and implementation between multiple processes, improve the utilization efficiency of CPU and memory resources, and reduce unnecessary occupation.

[0105] Therefore, the multi-core implementation of signal angle of arrival and polarization information estimation can be divided into two task modules, master core task and slave core task, and the priority scheduling function Task_yield() is used to switch between two tasks with the same priority in different cores. The semaphore module is used in the task to prevent multiple modules from executing at the same time, and when the operation of a function in a task is completed, the operation of a function in the next module is performed, realizing the communication between the master core and the slave core; the semaphore mainly includes mutual exclusion semaphore and counting semaphore, and the mutual exclusion semaphore only includes two states of 0 and 1; since the communication between the cores is relatively simple when estimating the angle of arrival, the function of the mutual exclusion semaphore is only to notify the running or suspension of the core task, and therefore the hardware implementation of the estimation algorithm system uses the mutual exclusion semaphore; when the semaphore is 1, the core is notified to run; if the semaphore is 0, the core is suspended and waits, and the semaphore can be activated through IPC (Inter-Processor Communication, inter-processor communication).

[0106] It can be understood that the IPC inter-processor communication mainly has several implementation modes including minimum use, increasing data path, increasing dynamic allocation, powerful but easy-to-use message mechanism, including Notify notification mechanism and MessageQ module. In order to transfer the shared memory address between the cores and unlock the semaphore in the simplest and most convenient way, the present application can use the inter-processor communication mode.

[0107] As Figure 5 and Figure 6As shown, the topology between the multiple cores in parallel operation can adopt a master-slave mode and a data flow mode. The master-slave mode selects one of the multiple cores as a master core and the others as slave cores, the master core is responsible for unified control, each core has an independent task, and the slave cores do not communicate with each other; the control content of the master core on the entire process mainly includes communication with the FPGA and receiving data, transmission of shared memory addresses among the cores, sending of notification information of running or waiting of the slave cores, notification information of waiting for completion of running of the cores, and transmission of data output by the slave cores; there is no message transmission among the slave cores, the slave core tasks are the same and the data are processed in parallel; in the data flow mode, each core depends on the processing result of the previous core.

[0108] It can be known that the data flow structure cannot achieve the purpose of simultaneous spectral peak search of eight cores, therefore, the system structure in the application adopts the master-slave mode, after the inter-core communication is started, the master core is connected with the slave cores, and event registration is performed on the inter-core connection; the message transmission between the master core and the slave core is performed through the Notify_sendEvent() function, in the system, before the master core sends information to the slave core, the task that needs to be completed by the master core is to receive and process data, and then the result is placed in the shared memory; the master core sends an event to the slave core after completing the task, the master core and the slave core send messages and enter the feedback function through the event number in the Notify_sendEvent() function, in the feedback function, after the shared memory address is transmitted and the semaphore is activated, the operation of the slave core can be performed, and when the seven slave cores complete the operation, the semaphore of the master core is activated, and the next operation of the master core is continued; before the semaphores of the cores are activated, the Semaphore_pend() function is used to make the cores always hang and wait.

[0109] In the specific embodiment of the application, the step of using the shared memory to transmit the noise subspace data by the DSP processor is as follows:

[0110] (1) the master core applies for a shared memory region and names the memory region, and divides appropriate memory space according to the size of the noise subspace matrix to be stored;

[0111] (2) the master core sends the address of the shared memory to each slave core, and each core performs address conversion after receiving the address;

[0112] (3) the slave core reads the autocovariance data of the noise subspace according to the shared memory address and performs first-stage spectral peak search operation.

[0113] As shown in Figure 7 the main steps of SRIO communication of the DSP processor are as follows:

[0114] (1) enable and initialize SRIO subsystem, set SRIO communication as normal mode, and configure as x4 link connection mode, set the device identification ID of DSP end;

[0115] (2) register doorbell interrupt by using Hwi, inform DSP main core to read data sent by FPGA to DSP, DSP responds to SRIO doorbell interrupt and reads data in interrupt service function;

[0116] (3) complete parallel processing operation of multi-core for angle of arrival and polarization information estimation in DSP.

[0117] DSP processor reads data in interrupt service program, as shown in Figure 8 the total flow of DSP implementation of signal angle of arrival-polarization estimation algorithm is shown in Figure 5 as shown in Figure 5 the module under task 0 is the task to be completed by main core 0, and the module under task 1 is the task to be completed by slave cores 1 to 7; the two tasks have the same priority, the switching between tasks uses the Task_yield() function, and the BIOS_exit(0) is used after all tasks are completed, the semaphore is used for communication between tasks, i.e. between main core and slave core; the specific content of tasks A, B, C and D in the flow chart, tasks A, B and D belong to main core tasks, 1, 2 and 3 represent the order of event completion in main core, task C belongs to slave core task, specifically:

[0118] task A: main core task 1

[0119] receive data from FPGA through SRIO, obtain noise subspace after characteristic decomposition, then write into shared memory, and send event to each slave core and transfer shared memory address, so that the slave core starts running from the suspended state.

[0120] task B: main core task 2

[0121] after sending event to each slave core, perform main core level direction finding, perform coarse and fine search, according to the division of the search range, the search range of main core 0 is θ∈(0°-23°), after completion of the first spectrum peak search, the main core is suspended for waiting, after all slave cores complete direction finding, receive the signals from seven slave cores running completion and the shared memory address of the running result obtained by the first spectrum peak coarse search; then activate the semaphore, and then perform main core task 3.

[0122] task C: slave core task

[0123] After receiving the event sent by the master core, the seven slave cores obtain the shared memory address and perform their respective address conversions, read the noise subspace autocorrelation matrix data from the shared memory, perform the first-level direction finding according to the divided range, and write the results into the shared memory. After each core completes the task, it sends a notification event and the shared memory address of the search result to the master core.

[0124] Task D: Master core task 3

[0125] After receiving the events from the seven slave cores and completing the first-level direction finding of the master core, the semaphore is activated, and the master core task 3 is performed. The master core reads the data written by the slave cores into the shared memory, arranges all the search results in descending order of spectral peak value, filters the first-level direction finding results through the corresponding peak value, and records the corresponding angle of arrival information. If the half-interval search method is used, the real and false spectral peaks need to be judged. According to the results of the azimuth and elevation angles, the accurate search is performed in the range of ±1° with a step of 0.1°, the second-level direction finding of the master core is completed, and the angle of arrival estimate value meeting the angle accuracy requirement is obtained. According to the estimate result of the angle of arrival, the master core estimates the polarization parameter, completes the remaining operations of the algorithm, and finally outputs the results of the angle of arrival and polarization angle.

[0126] In the entire data processing structure, the fixed memory area used by the data includes the data read from the FPGA and stored in the DDR3, and the results after the first-level direction finding of the master core are stored in the memory of the master core. The shared memory area mainly includes two parts: the data of the noise subspace stored by the master core and the first-level direction finding result data stored by the seven slave cores. Since the shared memory is used by eight cores at the same time, it should be divided into a master core storage area and a slave core storage area when used to avoid data overlap.

[0127] In addition, the verification receives an antenna array with a horizontal polarization dipole uniform circular array with 12 elements, a circular array radius of 15 m, and a short wave signal frequency of f = 17.565 MHz.

[0128] Table 2 shows the estimation results of the angle of arrival and polarization information in the DSP processor:

[0129] Table 2

[0130] Clock cycle Hardware time consumption Feature decomposition 1764587 1.765 ms Single core first stage spectral peak search 480841254 480.841 ms 8 core parallel first stage spectral peak search 58481248 58.484 ms Half interval search method 37957782 37.958 ms

[0131] Table 3 shows the clock cycles for completing each operation and the conversion of the clock number to the DSP running time:

[0132] Table 3

[0133]

[0134] As shown in Tables 2 and 3, this application, by employing a shortwave electromagnetic vector receiving antenna array and based on a DSP processor, can achieve rapid estimation of the angle of arrival-polarization of shortwave skywave propagation signals. The processing results are not only accurate but also fast, providing reliable theoretical and technical support for improving the quality of shortwave skywave signals, accurate direction finding and positioning of shortwave antenna signals, and research on the ionospheric radio wave propagation environment.

[0135] According to the method for estimating the angle of arrival and polarization information of shortwave skywave signals proposed in this application, a preset shortwave three-component polarized receiving antenna array is used to receive shortwave skywave signals. Based on the rank-deficient MUSIC algorithm and a multi-core parallel computing optimization strategy, corresponding array signal processing, source number estimation, and multi-level spectral peak search operations are performed in a preset DSP processor to obtain the estimated angle of arrival and polarization angle information of the shortwave skywave signal. This application simultaneously estimates the angle of arrival and polarization information of skywave signals based on an electromagnetic vector receiving antenna array and DSP processing method, thereby providing a basis for accurate direction finding of skywave signals, improving signal quality, and studying the ionospheric radio wave propagation environment.

[0136] Secondly, with reference to the accompanying drawings, an apparatus for estimating the angle of arrival-polarization information of shortwave skywave signals according to an embodiment of this application is described.

[0137] Figure 9 This is a block diagram of a device for estimating the angle of arrival and polarization information of a shortwave skywave signal according to an embodiment of this application.

[0138] like Figure 9 As shown, the shortwave skywave signal angle-polarization information estimation device 10 includes a receiving module 100 and an estimation module 200.

[0139] The receiving module 100 is used to receive shortwave skywave signals using a preset shortwave three-component polarized receiving antenna array.

[0140] The estimation module 200 is used to perform corresponding array signal processing, source number estimation and multi-level spectral peak search operations in a preset DSP processor based on the rank-deficient MUSIC algorithm and multi-core parallel computing optimization strategy, so as to obtain the arrival angle estimation information and polarization angle estimation information of the shortwave skywave signal.

[0141] Optionally, in one embodiment of this application, the shortwave skywave signal angle-polarization information estimation device 10 of this application embodiment further includes: a setting module and a processing module.

[0142] The setting module is used to determine the target multi-core processor corresponding to the DSP processor and the target FPGA development board corresponding to the preset FPGA chip before performing corresponding array signal processing, source number estimation and multi-level peak search operations in the preset DSP processor.

[0143] The processing module is configured to perform preset signal processing on the short-wave sky wave signal through the FPGA chip, and transmit the short-wave sky wave signal processed through the SRIO data interface from the target FPGA development board to the target multi-core processor of the operating system carrying the SYS / BIOS.

[0144] Optionally, in an embodiment of the present application, the estimation module 200 comprises a sampling unit, a calculation unit, a decomposition unit, a storage unit, a first determination unit and a searching unit.

[0145] The sampling unit is configured to sample the short-wave sky wave signal by using the short-wave three-component polarization receiving antenna array to obtain at least one snapshot sample point.

[0146] The calculation unit is configured to generate an array output signal according to the at least one snapshot sample point, and calculate a maximum likelihood estimation of a self-covariance matrix of the array output signal.

[0147] The decomposition unit is configured to perform eigenvalue decomposition on the self-covariance matrix of the array output signal based on the maximum likelihood estimation to obtain a plurality of eigenvalues.

[0148] The storage unit is configured to sort the plurality of eigenvalues to generate a signal subspace and a noise subspace, and store a matrix value of the noise subspace in a preset shared memory.

[0149] The first determination unit is configured to determine a first-level spectrum peak search range, a first-level search step value, a second-level spectrum peak search range and a second-level search step value corresponding to a multi-level spectrum peak search operation.

[0150] The searching unit is configured to perform the multi-level spectrum peak search operation based on the first-level spectrum peak search range, the first-level search step value, the second-level spectrum peak search range and the second-level search step value, and in combination with a preset spectrum density algorithm to obtain angle-of-arrival-polarization estimation information, wherein the angle-of-arrival estimation information and the polarization angle estimation information comprise an azimuth angle estimation value, an elevation angle estimation value, a polarization auxiliary angle estimation value and a polarization phase angle estimation value.

[0151] Optionally, in an embodiment of the present application, the estimation module 200 further comprises an acquisition unit, a first sorting unit, a first judgment unit, a second sorting unit and a second judgment unit.

[0152] The acquisition unit is configured to perform a first-level spectrum peak search operation in the first-level spectrum peak search range based on the first-level search step value to acquire position information and amplitude information of all spectrum peaks in the first-level spectrum peak search range.

[0153] The first sorting unit is configured to sort all the spectrum peaks in descending order according to the amplitude information, to obtain a first-level sorting result, and to obtain position information corresponding to the first K spectrum peaks in the first-level sorting result, so as to obtain a first-level spectrum peak search result of the short-wave sky wave signal through the position information corresponding to the first K spectrum peaks.

[0154] The first judging unit is configured to judge whether the first-level spectrum peak search result meets a preset accuracy requirement, wherein if the first-level spectrum peak search result meets the preset accuracy requirement, the first-level spectrum peak search operation is ended, and arrival angle estimation information is generated, and a polarization angle estimation operation is performed according to the arrival angle estimation information to obtain polarization angle estimation information, wherein K is a positive integer.

[0155] The second sorting unit is configured to, if the first-level spectrum peak search result does not meet the preset accuracy requirement, perform a second-level spectrum peak search operation in a second-level spectrum peak search range according to a second-level search step value, to obtain all the spectrum peaks in a second-level spectrum peak search region, and sort all the spectrum peaks in the second-level spectrum peak search region in descending order to obtain a second-level sorting result, and to obtain arrival angle information corresponding to the first K spectrum peaks in the second-level sorting result.

[0156] The second judging unit is configured to judge whether the arrival angle information meets the preset accuracy requirement, wherein if the preset accuracy requirement is not met, the second-level spectrum peak search operation is repeatedly performed, otherwise the second-level spectrum peak search operation is ended, and the arrival angle estimation information and the polarization angle estimation information are obtained.

[0157] Optionally, in an embodiment of the present application, the estimation module 200 further comprises a second determining unit, an execution unit, a sending unit, a third determining unit and a calling unit.

[0158] The second determining unit is configured to determine a plurality of overlapping interval critical values corresponding to the first-level spectrum peak search range, and to divide the first-level spectrum peak search range into a plurality of search intervals according to the plurality of overlapping interval critical values.

[0159] The execution unit is configured to perform the first-level spectrum peak search operation through the plurality of search intervals and the target multi-core processor, to obtain a maximum spectrum peak of each slave core and an azimuth angle and a pitch angle corresponding to the maximum spectrum peak.

[0160] The sending unit is configured to send the maximum spectrum peak of each slave core and the azimuth angle and the pitch angle corresponding to the maximum spectrum peak to the master core, so as to obtain a real spectrum peak through the master core according to the azimuth angle and the pitch angle corresponding to the maximum spectrum peak of each slave core.

[0161] The third determining unit is configured to determine an arrival angle corresponding to the real spectrum peak according to the azimuth angle and the pitch angle corresponding to the real spectrum peak, and to judge whether the arrival angle meets a preset range requirement.

[0162] The calling unit is configured to perform a second-level spectrum peak search operation according to a second-level search step value if the arrival angle meets the preset range requirement, and call a matrix value of the noise subspace in the shared memory through the target multi-core processor, so that the target multi-core processor performs parallel operation according to the matrix value of the noise subspace and a preset spectrum density algorithm to obtain the arrival angle estimation information and the polarization angle estimation information.

[0163] Optionally, in an embodiment of the present application, a mathematical expression of the preset spectrum density algorithm is as follows:

[0164]

[0165] wherein θ k represents an azimuth angle of the kth short-wave skywave signal; represents a pitch angle of the kth short-wave skywave signal; γ k represents a polarization auxiliary angle of the kth short-wave skywave signal; η k represents a polarization phase angle of the kth short-wave skywave signal; represents a steering vector of the array; h(γ, η) represents a polarization steering vector; U N represents a noise subspace; represents a conjugate transpose of the noise subspace; H represents the conjugate transpose.

[0166] It should be noted that the aforementioned explanation and description of the embodiment of the method for estimating the arrival angle-polarization information of the short-wave skywave signal also applies to the device for estimating the arrival angle-polarization information of the short-wave skywave signal, which will not be described here again.

[0167] The device for estimating the arrival angle-polarization information of the short-wave skywave signal according to the embodiment of the present application comprises a receiving module 100 configured to receive the short-wave skywave signal by using a preset short-wave three-component polarization receiving antenna array; and an estimating module 200 configured to perform corresponding array signal processing, source number estimation and multi-level spectrum peak search operation in a preset DSP processor based on a rank-deficient MUSIC algorithm and a multi-core parallel operation optimization strategy to obtain the arrival angle estimation information and the polarization angle estimation information of the short-wave skywave signal. According to the electromagnetic vector receiving antenna array and the DSP processing method, the arrival angle and the polarization information of the skywave signal are estimated simultaneously, thereby providing a basis for accurate direction finding of the skywave signal, improving the signal quality and studying the ionospheric wave propagation environment.

[0168] Figure 10 The electronic device provided in the embodiment of the present application has the structure as shown in the structural schematic diagram of the electronic device. The electronic device can comprise:

[0169] The memory 1001, the processor 1002 and the computer program stored in the memory 1001 and capable of running on the processor 1002.

[0170] The processor 1002 implements the short-wave sky wave signal angle-of-arrival-polarization information estimation method provided in the above embodiments when executing the program.

[0171] Further, the electronic device further comprises:

[0172] The communication interface 1003 is configured to communicate between the memory 1001 and the processor 1002.

[0173] The memory 1001 is configured to store the computer program capable of running on the processor 1002.

[0174] The memory 1001 can include a high-speed RAM memory, and can also include a non-volatile memory, for example, at least one disk memory.

[0175] If the memory 1001, the processor 1002 and the communication interface 1003 are independently implemented, the communication interface 1003, the memory 1001 and the processor 1002 can be connected to each other through a bus and complete communication between each other. The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component (PCI) bus or an Extended Industry Standard Architecture (EISA) bus, etc. The bus can be divided into an address bus, a data bus, a control bus, etc. For the convenience of representation, Figure 10 Only one thick line is used in the figure, but it does not mean that there is only one bus or only one type of bus.

[0176] Optionally, in a specific implementation, if the memory 1001, the processor 1002 and the communication interface 1003 are integrated on a chip, the memory 1001, the processor 1002 and the communication interface 1003 can complete communication between each other through an internal interface.

[0177] The processor 1002 can be a central processing unit (CPU), or an application specific integrated circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of the present application.

[0178] The embodiment of the present application further provides a computer readable storage medium, which stores a computer program, and the computer program is executed by a processor to implement the above short-wave sky wave signal angle-of-arrival-polarization information estimation method.

[0179] The embodiment of the present application further provides a computer program product, which comprises a computer program, and the computer program is executed to implement the above short-wave sky wave signal angle-of-arrival-polarization information estimation method.

[0180] In the description of the present specification, the description of the terms "one embodiment", "some embodiments", "an example", "a specific example", or "some examples" and the like means that the specific features, structures, materials or characteristics described in combination with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or N embodiments or examples in a suitable manner. In addition, the person skilled in the art can combine and combine the different embodiments or examples described in the present specification and the features of the different embodiments or examples without contradiction.

[0181] In addition, the terms "first", "second" are only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Therefore, the features defined with "first", "second" can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "N" is at least two, for example, two, three, etc., unless otherwise explicitly specified.

[0182] Any process or method descriptions in flow charts or otherwise described herein can be understood as representing code modules, segments, or portions of code that include one or more executable instructions for implementing the specified logic functions or processes, and the preferred embodiments of the present application also include additional implementation examples, in which the functions can be performed in different orders, in substantially simultaneous fashion, or in reverse order, depending on the functionality involved, as would be understood by persons skilled in the art of the embodiments described herein.

[0183] The logic and / or steps represented in the flowcharts and / or described herein, for example, can be considered as a sequence of executable instructions stored in a computer readable medium, which can be executed by an instruction execution system, apparatus or device, such as a computer-based system, a processor-based system, or other system that can fetch the instructions from the instruction execution system, apparatus or device and execute the instructions, or a combination of them. For the purposes of this specification, a "computer readable medium" can be any apparatus that can contain, store, communicate, propagate, or transport the program for use by or in connection with the instruction execution system, apparatus or device. The computer readable medium can be a computer readable storage medium or a computer readable signal medium. The computer readable storage medium can include, but is not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or a propagation medium. The computer readable signal medium can include, but is not limited to, a computer readable medium that facilitates transfer of the program from one place to another. A specific example of a computer readable medium is a non-transitory computer-readable storage medium. A specific example of a computer readable signal medium is a source or destination of the computer readable medium. Another specific example of a computer readable signal medium is a computer readable signal travelling through space. Thus, a computer readable medium can take many forms of hardware to carry out the program for use by or in connection with the instruction execution system, apparatus or device.

[0184] It should be understood that aspects of the application can be implemented in hardware, software, firmware or combinations thereof. In the above embodiments, the N steps or methods can be implemented in software or firmware stored in a memory and executed by a suitable instruction execution system. If implemented in hardware and in another embodiment, the hardware can be implemented with any or a combination of the following technologies, which are all well known in the art: a discrete logic circuit(s) having logic gates for implementing logic functions upon an application of data signals, an application specific integrated circuit having appropriate combinational logic gates, a programmable gate array(s) (PGA), a field programmable gate array (FPGA), etc.

[0185] Those of skill in the art would understand that the steps of the methods carried out above can be carried out wholly or partly by program instructions which can be stored in a computer readable storage medium and which, when executed, include one or a combination of the steps of the methods.

[0186] In addition, each of the functional units in the various embodiments of the present application can be integrated in one processing module, or each of the units can be physically present separately, or two or more units can be integrated in one module. The integrated module can be implemented in the form of hardware or in the form of a software functional module. When the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it can also be stored in a computer readable storage medium.

[0187] The storage medium mentioned above can be a read-only memory, a magnetic disk or an optical disk, etc. Although the embodiments of the present application have been shown and described above, it should be understood that the above embodiments are exemplary and should not be construed as limiting the present application, and those skilled in the art can make changes, modifications, replacements and variations to the above embodiments within the scope of the present application.

Claims

1. A method for estimating angle-of-arrival-polarization information of a short-wave skywave signal, characterized in that, The method comprises the following steps: receiving a short wave sky wave signal by using a preset short wave three-component polarization receiving antenna array; performing corresponding array signal processing, source number estimation and multi-stage spectrum peak search operation in a preset DSP processor based on a rank-deficient MUSIC algorithm and a multi-core parallel operation optimization strategy to obtain arrival angle estimation information and polarization angle estimation information of the short wave sky wave signal; The multi-core parallel operation optimization strategy comprises: determining a plurality of overlapable interval critical values corresponding to a first-stage spectrum peak search range, and dividing the first-stage spectrum peak search range into a plurality of search intervals according to the plurality of overlapable interval critical values; performing a first-stage spectrum peak search operation by using the plurality of search intervals and a target multi-core processor to obtain a maximum spectrum peak of a master core and each slave core of the multi-core processor and an azimuth angle and an elevation angle corresponding to the maximum spectrum peak; sending the maximum spectrum peak of each slave core and the azimuth angle and the elevation angle corresponding to the maximum spectrum peak to the master core, so as to obtain a real spectrum peak according to the azimuth angle and the elevation angle corresponding to the maximum spectrum peak of each slave core by using the master core; determining an arrival angle corresponding to the real spectrum peak according to the azimuth angle and the elevation angle corresponding to the real spectrum peak, and judging whether the arrival angle meets a preset range requirement; if the arrival angle meets the preset range requirement, performing a second-stage spectrum peak search operation according to a second-stage search step value, and calling a matrix value of a noise subspace in a shared memory by using the target multi-core processor, so that the target multi-core processor performs parallel operation according to the matrix value of the noise subspace and the preset spectrum density algorithm to obtain the arrival angle estimation information and the polarization angle estimation information.

2. The method of claim 1, wherein, Before performing corresponding array signal processing, source number estimation and multi-stage spectrum peak search operation in the preset DSP processor, the method further comprises: determining a target multi-core processor corresponding to the DSP processor and a target FPGA development board corresponding to a preset FPGA chip; performing preset signal processing on the short wave sky wave signal by using the FPGA chip, and transmitting the short wave sky wave signal processed by the signal processing from the target FPGA development board to a target multi-core processor of an operating system carrying SYS / BIOS by using an SRIO data interface.

3. The method of claim 1, wherein, The rank-deficient MUSIC algorithm comprises: sampling the short wave sky wave signal by using the short wave three-component polarization receiving antenna array to obtain at least one snapshot sample point; generating an array output signal according to the at least one snapshot sample point, and calculating a maximum likelihood estimation of a self-covariance matrix of the array output signal; performing characteristic decomposition on the self-covariance matrix of the array output signal based on the maximum likelihood estimation to obtain a plurality of characteristic values; sorting the plurality of characteristic values to generate a signal subspace and a noise subspace, and storing a matrix value of the noise subspace in a preset shared memory; determining a first-stage spectrum peak search range, a first-stage search step value, a second-stage spectrum peak search range and a second-stage search step value corresponding to a multi-stage spectrum peak search operation; performing a multi-level spectrum peak search operation based on the first-level spectrum peak search range, the first-level search step value, the second-level spectrum peak search range and the second-level search step value, and in combination with a preset spectrum density algorithm, to obtain the angle of arrival estimation information and the polarization angle estimation information, wherein the angle of arrival estimation information and the polarization angle estimation information include an azimuth angle estimation value, an elevation angle estimation value, a polarization auxiliary angle estimation value and a polarization phase angle estimation value.

4. The method of claim 3, wherein, The performing of the corresponding array signal processing, the number of sources estimation and the multi-level spectrum peak search operation in the preset DSP processor to obtain the angle of arrival estimation information and the polarization angle estimation information of the short-wave skywave signal includes: performing a first-level spectrum peak search operation in the first-level spectrum peak search range based on the first-level search step value, to obtain position information and amplitude information of all spectrum peaks in the first-level spectrum peak search range; performing a descending order sorting on the all spectrum peaks according to the amplitude information to obtain a first-level sorting result, and obtaining position information corresponding to the first K spectrum peaks of the first-level sorting result, so as to obtain a first-level spectrum peak search result of the short-wave skywave signal through the position information corresponding to the first K spectrum peaks; judging whether the first-level spectrum peak search result meets a preset accuracy requirement, wherein if the first-level spectrum peak search result meets the preset accuracy requirement, the first-level spectrum peak search operation is ended, the angle of arrival estimation information is generated, and a polarization angle estimation operation is performed according to the angle of arrival estimation information to obtain polarization angle estimation information, wherein K is a positive integer; if the first-level spectrum peak search result does not meet the preset accuracy requirement, performing a second-level spectrum peak search operation in the second-level spectrum peak search range according to the second-level search step value to obtain all spectrum peaks in the second-level spectrum peak search region, and performing a descending order sorting on the all spectrum peaks in the second-level spectrum peak search region to obtain a second-level sorting result, and obtaining angle of arrival information corresponding to the first K spectrum peaks of the second-level sorting result; judging whether the angle of arrival information meets the preset accuracy requirement, wherein if the preset accuracy requirement is not met, the second-level spectrum peak search operation is repeatedly performed, otherwise the second-level spectrum peak search operation is ended, and the angle of arrival estimation information and the polarization angle estimation information are obtained.

5. The method of claim 3, wherein, The mathematical expression of the preset spectrum density algorithm is: wherein denotes the azimuth angle of the k th shortwave skywave signal; denotes the elevation angle of the k th shortwave skywave signal; denotes the polarization auxiliary angle of the k th shortwave skywave signal; denotes the polarization phase angle of the k th shortwave skywave signal; D , denotes the steering vector of the array; h , denotes the polarization steering vector; denotes the noise subspace; denotes the conjugate transpose of the noise subspace; H denotes the conjugate transpose.​​ 6. An apparatus for estimating angle-of-arrival-polarization information of a short-wave skywave signal, characterized by comprising: including: The receiving module is configured to receive the short-wave skywave signal by using a preset short-wave three-component polarization receiving antenna array. The estimating module is configured to perform the corresponding array signal processing, the number of sources estimation and the multi-level spectrum peak search operation in the preset DSP processor based on the rank-deficient MUSIC algorithm and the multi-core parallel operation optimization strategy, to obtain the angle of arrival estimation information and the polarization angle estimation information of the short-wave skywave signal. The estimating module includes: The second determining unit is configured to determine a plurality of overlapping interval critical values corresponding to the first-level spectrum peak search range, and divide the first-level spectrum peak search range into a plurality of search intervals averagely according to the plurality of overlapping interval critical values. The execution unit is configured to perform a first-stage spectrum peak search operation through a plurality of search intervals and a target multi-core processor to obtain a maximum spectrum peak of a master core and each slave core in the multi-core processor and an azimuth angle and an elevation angle corresponding to the maximum spectrum peak; The sending unit is configured to send the maximum spectrum peak of each slave core and the azimuth angle and the elevation angle corresponding to the maximum spectrum peak to the master core, so as to obtain a real spectrum peak according to the azimuth angle and the elevation angle corresponding to the maximum spectrum peak of each slave core by the master core; The third determination unit is configured to determine an angle of arrival corresponding to the real spectrum peak according to the azimuth angle and the elevation angle corresponding to the real spectrum peak, and determine whether the angle of arrival meets a preset range requirement; The calling unit is configured to perform a second-stage spectrum peak search operation according to a second-stage search step value if the angle of arrival meets the preset range requirement, and call a matrix value of a noise subspace in a shared memory through the target multi-core processor, so that the target multi-core processor performs parallel operation according to the matrix value of the noise subspace and the preset spectrum density algorithm to obtain the angle of arrival estimation information and the polarization angle estimation information.

7. An electronic device, comprising: Comprising: A memory, a processor and a computer program stored on the memory and executable on the processor, the processor executing the program to implement the method for estimating the angle of arrival-polarization information of the short-wave skywave signal according to any one of claims 1-5.

8. A computer-readable storage medium having stored thereon a computer program, characterized in that, The computer program is executed by the processor to implement the method for estimating the angle of arrival-polarization information of the short-wave skywave signal according to any one of claims 1-5.

9. A computer program product comprising a computer program, characterized in that, The computer program is executed to implement the method for estimating the angle of arrival-polarization information of the short-wave skywave signal according to any one of claims 1-5.

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