A direction finding positioning method, device and readable storage medium of single satellite channel multiplexing

Abstract

This invention provides a direction finding and positioning method, device, and readable storage medium for single-satellite channel multiplexing. The method includes: determining the interferometer baseline and arranging the antenna array; designing the beamwidth and number of DBF de-ambiguity beams based on the principle that "the interferometer's coverage area is consistent with the coverage area of ​​multiple DBF amplitude comparison beams, and the DBF amplitude comparison accuracy is better than half of the unambiguous field of view"; performing DBF processing on the signals received by all antennas; using the DBF amplitude comparison beams for signal detection and parameter measurement; guiding the interferometer channel to complete the interferometer's phase measurement based on the measured parameters; using the direction of arrival measured by the DBF amplitude comparison beams to resolve the phase difference ambiguity in the interferometer's direction finding, thus completing the direction finding; and completing the target positioning calculation based on the direction finding results. This invention, through antenna layout design and the flexible pointing of the DBF beams, achieves DBF amplitude comparison direction finding to resolve the phase difference ambiguity in the interferometer's direction finding, thereby improving both signal detection sensitivity and the interferometer's de-ambiguity direction finding performance.

Description

Technical Field

[0001] This invention relates to the field of signal processing technology, and more specifically, to a direction finding and positioning method for single-satellite channel multiplexing. Background Technology

[0002] Single-satellite orientation positioning uses the phase difference information of the incident signal to calculate the angle 90-β between the target signal and two baselines (X-dimensional and Y-dimensional). x and 90-β y It combines the position, attitude, and velocity information of the satellite platform to complete the positioning calculation, such as... Figure 1 As shown. Single-satellite direction finding and positioning systems mainly include multi-beam amplitude comparison direction finding and interferometric direction finding. Multi-beam amplitude comparison direction finding determines the signal arrival angle by comparing the signal amplitudes received by two or three adjacent narrow beams among multiple simultaneously existing narrow beams distributed in the airspace. This method has high requirements for antenna beamwidth and gain, typically requiring an array configuration to form a high-gain narrow beam that meets the requirements. However, arrays require significant volume, weight, and size, which is costly for single-satellite payloads. Multi-baseline interferometric direction finding utilizes the phase difference between signals received by antennas located on different wavefronts, and obtains the direction of arrival through signal processing. Multiple baselines are used to resolve phase ambiguity. This method has a large direction finding error at large incident angles, requires long baseline lengths in the low-frequency band, and has low sensitivity, making it difficult to meet the requirements of single-satellite interferometers.

[0003] In some single-satellite direction finding methods, the amplitude comparison direction finding results from three element antennas are used to resolve phase difference ambiguities in the direction finding of a one-dimensional linear interferometer. This one-dimensional linear interferometer consists of four element antennas (A0, A1, A2, A3) forming three baselines, capable of accurate direction finding of signals from 8 to 18 GHz within a normal angle range of ±45°. Each element antenna has a 3dB beamwidth of ±60° at 8 GHz and ±45° at 18 GHz. Therefore, the final element antenna arrangement for the "amplitude comparison + interferometer" direction finding is as follows... Figure 2 As shown. Figure 2 The axes of two antenna units, A4 and A5, are rotated 45° to the left and right respectively, and A2 is selected in the interferometer antenna array to complete the three-antenna amplitude comparison direction finding function. In this design, one antenna unit is shared between amplitude comparison direction finding and interferometer direction finding. Therefore, the entire "amplitude comparison + interferometer" direction finding is achieved by six identical antenna units located on the same straight line, which also helps improve the maintainability of the entire direction finding system. However, this scheme uses a single antenna detection channel, resulting in low system sensitivity, which cannot meet the requirements for single-satellite signal reception. Summary of the Invention

[0004] The present invention aims to at least solve one of the technical problems in the existing single-satellite direction finding and positioning technology system, which is limited in application by the system sensitivity, direction finding deambiguity performance requirements, and payload size, and the application scope of various methods is not wide enough.

[0005] Therefore, the first aspect of the present invention provides a direction finding and positioning method for single-satellite channel multiplexing.

[0006] A second aspect of the present invention provides a computer device.

[0007] A third aspect of the present invention provides a computer-readable storage medium.

[0008] The direction finding and positioning method for single-satellite channel multiplexing proposed in this invention includes:

[0009] Determine the interferometer baseline and arrange the antenna array;

[0010] Based on the principle that "the spatial domain covered by the interferometer is consistent with the spatial domain covered by the multi-DBF amplitude comparison beam and the DBF amplitude comparison accuracy is better than half of the unambiguous field of view", the beamwidth and number of DBF deambiguity beams are designed.

[0011] DBF processing is performed on all signals received by the antennas;

[0012] Signal detection and parameter measurement are performed using DBF amplitude comparison beamforming.

[0013] The interferometer channel is guided to complete the phase measurement of the interferometer based on the measured parameters;

[0014] The direction of arrival measured by DBF amplitude beamforming is used to resolve the phase difference ambiguity in the interferometer direction finding, thus completing the direction finding.

[0015] The target location calculation is completed based on the direction finding results.

[0016] The direction finding and positioning method for single-satellite channel multiplexing according to the above-described technical solution of the present invention may also have the following additional technical features:

[0017] In the above technical solution, determining the interferometer baseline and arranging the antenna array includes:

[0018] The interferometer baseline is formed using the two antennas furthest apart.

[0019] The antennas in the antenna array are arranged sequentially at equal intervals.

[0020] In the above technical solution, the DBF processing of the signals received by all antennas includes:

[0021] The signals received by each antenna are filtered, amplified, and down-converted by the radio frequency front end;

[0022] The signal that has undergone filtering, amplification, and downconversion is converted into an analog-to-digital converter (AD).

[0023] In the above technical solution, the signal detection and parameter measurement using DBF amplitude comparison beam includes:

[0024] The DBF beam is oriented according to the beamwidth interval of the DBF beam to cover the coverage area of ​​the interferometer antenna's main beam.

[0025] Amplitude comparison and direction finding are performed using DBF beamforming.

[0026] In the above technical solution, the phase difference ambiguity of the direction finding of the incoming wave direction measured by the DBF amplitude comparison beam interferometer includes:

[0027] Confirm the unambiguous field of view where the phase of the interferometer is located.

[0028] In the above technical solution, the interferometer's coverage space is consistent with the multi-DBF amplitude comparison beam coverage space, including:

[0029] Following the DBF amplitude comparison beam 3dB overlap principle, multiple amplitude comparison beams are formed simultaneously to match the coverage range of the interferometer beam.

[0030] In the above technical solution, the DBF amplitude comparison accuracy being better than half of the unblurred field of view includes:

[0031] The sum of the accuracy and measurement error of DBF amplitude comparison direction finding is less than half that of unambiguous field of view.

[0032] In the above technical solution, when the interferometer phase difference is 180°, the calculation method for the unambiguous field of view is as follows:

[0033]

[0034] Where, θ U For an unambiguous field of view, λ is the incident wavelength, and d is the antenna size.

[0035] The present invention also provides a computer device, the computer device including a processor and a memory, the memory storing a computer program, the computer program being loaded and executed by the processor to implement the single-satellite channel multiplexing direction finding and positioning method as described in any of the above technical solutions.

[0036] The present invention also provides a computer-readable storage medium, characterized in that the storage medium stores a computer program, which is loaded and executed by a processor to implement the direction finding and positioning method for single-satellite channel multiplexing as described in any of the above technical solutions.

[0037] In summary, due to the adoption of the above-mentioned technical features, the beneficial effects of the present invention are:

[0038] By fully utilizing the resources released by the satellite platform and using data from closely arranged multi-antenna channels to complete DBF digital beamforming before signal detection, the system processing gain is improved, enabling high-sensitivity signal detection. Information such as beam amplitude is extracted for amplitude comparison and direction finding. Simultaneously, the interferometer channel (interferometer channel and DBF channel multiplexed) is guided to extract phase information for interferometer direction finding. Through antenna layout design and the flexible pointing of the DBF beam, the phase difference ambiguity of interferometer direction finding is resolved by DBF amplitude comparison and direction finding, which improves both signal detection sensitivity and interferometer de-ambiguity direction finding performance.

[0039] Additional aspects and advantages of the invention will become apparent in the following description or may be learned by practice of the invention. Attached Figure Description

[0040] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0041] Figure 1 This is a schematic diagram showing the positional relationship between the antenna array and the radiation source in single-satellite direction finding and positioning.

[0042] Figure 2 This is a diagram of the unit antenna arrangement for traditional "amplitude comparison + interferometer" direction finding;

[0043] Figure 3 This is a schematic diagram of the linear array channels in a direction finding and positioning method for single-satellite channel multiplexing according to an embodiment of the present invention;

[0044] Figure 4 This is a schematic diagram illustrating the principle of incident angle ambiguity caused by interferometer phase ambiguity in a direction finding and positioning method for single-satellite channel multiplexing according to an embodiment of the present invention;

[0045] Figure 5 This is a schematic diagram of the ambiguity principle of the amplitude comparison direction finding and deinterferometer in the direction finding and positioning method for single-satellite channel multiplexing according to an embodiment of the present invention;

[0046] Figure 6 This is a schematic diagram of the coverage range of the DBF amplitude comparison beam and the interferometer beam in a direction finding and positioning method for single-satellite channel multiplexing according to an embodiment of the present invention;

[0047] Figure 7 This is a schematic diagram of the baseline of the two-dimensional interferometer in the third embodiment of the present invention;

[0048] Figure 8 This is a schematic diagram of beamforming in the third embodiment of the present invention;

[0049] Figure 9 This is a simulation comparison diagram of the coverage range of the DBF amplitude comparison beam and the interferometer beam at different frequencies in the third embodiment of the present invention. Detailed Implementation

[0050] To better understand the above-mentioned objectives, features, and advantages of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0051] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and therefore the scope of protection of the invention is not limited to the specific embodiments disclosed below.

[0052] The following reference Figures 3 to 9 This describes a direction finding and positioning method, apparatus, and readable storage medium for single-satellite channel multiplexing provided according to some embodiments of the present invention.

[0053] Some embodiments of this application provide a direction finding and positioning method for single-satellite channel multiplexing.

[0054] like Figures 3 to 6 As shown, the first embodiment of the present invention proposes a direction finding and positioning method for single-satellite channel multiplexing, including the following steps:

[0055] Determine the interferometer baseline and arrange the antenna array;

[0056] Specifically, determining the interferometer baseline and arranging the antenna array includes:

[0057] The interferometer baseline is formed using the two antennas furthest apart.

[0058] The antennas in the antenna array are arranged sequentially at equal intervals.

[0059] Based on the principle that "the spatial domain covered by the interferometer is consistent with the spatial domain covered by the multi-DBF amplitude comparison beam and the DBF amplitude comparison accuracy is better than half of the unambiguous field of view", the beamwidth and number of DBF deambiguity beams are designed.

[0060] Specifically, the interferometer's coverage space is consistent with the multi-DBF amplitude comparison beam coverage space, including:

[0061] Following the DBF amplitude comparison beam 3dB overlap principle, multiple amplitude comparison beams are formed simultaneously to match the coverage range of the interferometer beam.

[0062] The DBF amplitude comparison accuracy being better than half that of the unblurred field of view includes:

[0063] The sum of the accuracy and measurement error of DBF amplitude comparison direction finding is less than half that of unambiguous field of view.

[0064] DBF processing is performed on all signals received by the antennas;

[0065] Specifically, the DBF processing of the signals received by all antennas includes:

[0066] The signals received by each antenna are filtered, amplified, and down-converted by the radio frequency front end;

[0067] The signal that has undergone filtering, amplification, and downconversion is converted into an analog-to-digital converter (AD).

[0068] Signal detection and parameter measurement are performed using DBF amplitude comparison beamforming.

[0069] Specifically, the signal detection and parameter measurement using DBF amplitude comparison beams include:

[0070] The DBF beam is oriented according to the beamwidth interval of the DBF beam to cover the coverage area of ​​the interferometer antenna's main beam.

[0071] Amplitude comparison and direction finding are performed using DBF beamforming.

[0072] The interferometer channel is guided to complete the phase measurement of the interferometer based on the measured parameters;

[0073] The direction of arrival measured by DBF amplitude beamforming is used to resolve the phase difference ambiguity in the interferometer direction finding, thus completing the direction finding.

[0074] Specifically, the phase difference ambiguity in the direction finding of the incoming wave direction measured by the DBF amplitude comparison beam interferometer includes:

[0075] Confirm the unambiguous field of view where the phase of the interferometer is located.

[0076] The target location calculation is completed based on the direction finding results.

[0077] The second embodiment of the present invention proposes a direction finding and positioning method for single-satellite channel multiplexing, and, based on the first embodiment, as follows: Figure 3 As shown, since the single-satellite platform has strict constraints on the size of the antenna array, assuming that the single-satellite payload requires the antenna size to be d, in order to make full use of the resources released by the satellite platform, the antennas are arranged closely together. At this time, the number of antennas is n+1, that is, the distance between adjacent antennas is d / n.

[0078] To ensure direction finding accuracy, the interferometer baseline is formed using the farthest antennas, A0 and An. At the digital receiver, the signals received by antennas A0, A1, A2...An are processed by digital beamforming (DBF) to form m digital beams. Through specific weights, the DBF beams are aligned according to their beamwidth intervals to cover the coverage area of ​​the interferometer antenna's main beam. After using the DBF beams for amplitude comparison and coarse direction finding, the interferometer is guided to complete phase deambiguity resolution, thereby completing direction finding deambiguity resolution and target localization.

[0079] Figure 4 This illustrates the incident angle ambiguity caused by interferometer phase ambiguity, where θ is the signal incident angle. U For an unambiguous field of view, λ is the incident wavelength.

[0080] From the interferometer phase difference formula:

[0081]

[0082] A blur-free field of view can be obtained, that is hour:

[0083]

[0084] By measuring the approximate range of the signal angle using amplitude comparison direction finding, and confirming which unambiguous interval the phase of the interferometer falls within, a high-precision direction finding result can be obtained.

[0085] Figure 5 A schematic diagram of an amplitude-comparison direction-finding interferometer is shown, where θ 干涉仪 θ represents the measurement accuracy of the interferometer. 比幅 and θ 比幅2 This indicates the amplitude-to-direction-finding accuracy under two different conditions, such as... Figure 5 As shown, when the sum of the accuracy of amplitude-based direction finding and the measurement error is better than θ... U When / 2, that is, less than θ U When the beamwidth is 1 / 2, the amplitude comparison direction finding results can be used to resolve the phase difference ambiguity of the interferometer. In engineering, amplitude comparison direction finding interferometers can typically achieve beamwidths of 1 / 10 to 1 / 4, from which the required amplitude comparison beamwidth can be calculated, and the ambiguity can be resolved by flexibly configuring the DBF parameters.

[0086] Figure 6 A schematic diagram of the coverage range of the DBF amplitude comparison beam and the interferometer beam is shown. According to the 3dB overlap principle of the DBF amplitude comparison beam, multiple amplitude comparison beams are formed at the same time to make them consistent with the coverage range of the interferometer beam. At this time, the DBF amplitude comparison beam can complete the deblurring of the interferometer.

[0087] The specific steps of the direction finding and positioning method using single-satellite channel multiplexing are as follows:

[0088] 1. Determine the longest interferometer baseline based on the maximum antenna size, and arrange the antenna array closely;

[0089] 2. Based on the principle that "the spatial domain covered by the interferometer is consistent with the spatial domain covered by the multi-DBF amplitude comparison beam, and the DBF amplitude comparison accuracy is better than half of the unambiguous field of view", design the beamwidth and number of DBF deambiguity beams;

[0090] All signals received by the antennas are filtered, amplified, down-converted, and then converted to analog-to-digital converters by the radio frequency front end.

[0091] High-sensitivity signal detection and parameter measurement are accomplished using DBF amplitude-comparison beamforming.

[0092] The interferometer channel is guided to complete the phase measurement based on the measured parameters;

[0093] High-precision direction finding is achieved by using the direction of arrival measured by DBF amplitude beamforming to resolve the phase difference ambiguity in the interferometer direction finding.

[0094] The target location calculation is completed based on the direction finding results.

[0095] The third embodiment of this invention proposes a direction finding and positioning method using single-satellite channel multiplexing. Based on any of the above embodiments, it employs two 6-element 0.8–1.4 GHz antennas in each dimension, using the elements at both ends of two one-dimensional linear arrays to form the interferometer baseline. The baseline lengths for both the azimuth and elevation dimensions are 500 mm. Figure 7 As shown.

[0096] Using two one-dimensional linear arrays, three beams are formed in the elevation and azimuth dimensions, respectively, such as... Figure 8 As shown.

[0097] Figure 9 The simulation of the coverage range of the DBF amplitude comparison beam and the interferometer beam is shown, so that the spatial domain covered by the interferometer is consistent with the spatial domain covered by the multi-DBF amplitude comparison beam.

[0098] The amplitude-ratio direction-finding accuracy of the synthetic beam is shown in the table below:

[0099]

[0100] The phase of the interferometer is directly de-ambigued using the synthesized beam amplitude direction finding. Its de-ambiguity capability is shown in the table below:

[0101]

[0102] By using a synthesized beam for amplitude comparison and direction finding, the accuracy (angle) of the amplitude comparison and direction finding is less than the distribution angle of the phase ambiguity of the interferometer, which can effectively complete the deambiguity of the interferometer phase and thus achieve high-precision positioning.

[0103] A fourth embodiment of the present invention provides a computer device, the computer device including a processor and a memory, the memory storing a computer program, the computer program being loaded and executed by the processor to implement the single-satellite channel multiplexing direction finding and positioning method as described in any of the above embodiments.

[0104] The fifth embodiment of the present invention provides a computer-readable storage medium storing a computer program, which is loaded and executed by a processor to implement the single-satellite channel multiplexing direction finding and positioning method as described in any of the above embodiments.

[0105] In this specification, the illustrative expressions of the terms used do not necessarily refer to the same embodiments or examples. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0106] Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this invention shall be included within the scope of protection of this invention.

Claims

1. A direction finding and positioning method using single-satellite channel multiplexing, characterized in that, include: Determine the interferometer baseline and arrange the antenna array; Based on the principle that "the spatial domain covered by the interferometer is consistent with the spatial domain covered by the multi-DBF amplitude comparison beam and the DBF amplitude comparison accuracy is better than half of the unambiguous field of view", the beamwidth and number of DBF deambiguity beams are designed. DBF processing is performed on all signals received by the antennas; Signal detection and parameter measurement are performed using DBF amplitude comparison beamforming. The interferometer channel is guided to complete the phase measurement of the interferometer based on the measured parameters; The direction of arrival measured by DBF amplitude beamforming is used to resolve the phase difference ambiguity in the interferometer direction finding, thus completing the direction finding. The target location calculation is completed based on the direction finding results.

2. The direction finding and positioning method for single-satellite channel multiplexing according to claim 1, characterized in that, The determination of the interferometer baseline and the arrangement of the antenna array include: The interferometer baseline is formed using the two antennas furthest apart. The antennas in the antenna array are arranged sequentially at equal intervals.

3. The direction finding and positioning method for single-satellite channel multiplexing according to claim 2, characterized in that, The DBF processing of all signals received by the antennas includes: The signals received by each antenna are filtered, amplified, and down-converted by the radio frequency front end; The signal that has undergone filtering, amplification, and downconversion is converted into an analog-to-digital converter (AD).

4. The direction finding and positioning method for single-satellite channel multiplexing according to claim 3, characterized in that, The signal detection and parameter measurement using DBF amplitude comparison beamforming includes: The DBF beam is oriented according to the beamwidth interval of the DBF beam to cover the coverage area of ​​the interferometer antenna's main beam. Amplitude comparison and direction finding are performed using DBF beamforming.

5. The direction finding and positioning method for single-satellite channel multiplexing according to claim 4, characterized in that, The phase difference ambiguity in the direction finding of the incoming wave direction measured by the DBF amplitude comparison beam interferometer includes: Confirm the unambiguous field of view where the phase of the interferometer is located.

6. The direction finding and positioning method for single-satellite channel multiplexing according to claim 5, characterized in that, The interferometer's coverage area is consistent with the multi-DBF amplitude-comparison beam coverage area, including: Following the DBF amplitude comparison beam 3dB overlap principle, multiple amplitude comparison beams are formed simultaneously to match the coverage range of the interferometer beam.

7. The direction finding and positioning method for single-satellite channel multiplexing according to claim 6, characterized in that, The DBF amplitude comparison accuracy being better than half that of the unblurred field of view includes: The sum of the accuracy and measurement error of DBF amplitude comparison direction finding is less than half that of unambiguous field of view.

8. The direction finding and positioning method for single-satellite channel multiplexing according to claim 7, characterized in that, When the phase difference of the interferometer is 180°, the calculation method for the unambiguous field of view is as follows: Where, θ U For an unambiguous field of view, λ is the incident wavelength, and d is the antenna size.

9. A computer device, characterized in that, The computer device includes a processor and a memory, the memory storing a computer program, which is loaded and executed by the processor to implement the single-satellite channel multiplexing direction finding and positioning method as described in any one of claims 1 to 8.

10. A computer-readable storage medium, characterized in that, The storage medium stores a computer program, which is loaded and executed by a processor to implement the single-satellite channel multiplexing direction finding and positioning method as described in any one of claims 1 to 8.

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