Anti-interference direction finding and short message communication device based on Beidou satellite array antenna

Abstract

The invention discloses an anti-interference direction finding and short message communication device based on a Beidou satellite array antenna. The device comprises a master terminal machine and a slave terminal machine, the master terminal machine is electrically connected with the slave terminal machine; each of the master terminal machine and the slave terminal machine comprises a Beidou satellite array antenna module, an anti-interference baseband signal processing module, an RTK precise direction finding resolving module and a navigation information processing module which are independent from each other; the master terminal machine further comprises a short message communication module; the Beidou satellite array antenna module is used for receiving Beidou satellite frequency point signals, and the anti-interference baseband signal processing module is used for carrying out baseband processing on the processed Beidou satellite frequency point signals to obtain baseband processing signals. The RTK precise direction finding resolving module and the navigation information processing module are respectively used for carrying out operation processing on the baseband processing signal to obtain a direction finding result and navigation information, and the short message communication module is used for completing sending and receiving of a short message. The device provided by the invention realizes reliable and accurate Beidou satellite navigation direction finding and short message data communication in a complex electromagnetic environment.

Description

Technical Field

[0001] The present invention relates to the field of satellite navigation technology, and in particular to an anti-interference direction-finding and short message communication device based on a Beidou satellite array antenna. Background Art

[0002] The Global Navigation Satellite System (GNSS) holds significant military applications. While it has experienced rapid development over the past two decades, it has also exposed the vulnerability of navigation signals to interference. Modern warfare is conducted in complex electromagnetic environments, and future integrated air and space warfare, in particular, will face an even more complex and volatile spatial environment. Currently, my country is at a critical juncture in the industrialization and application of the Beidou-3 satellite navigation and positioning system. Research on a device based on Beidou satellite anti-interference array antennas that integrates conventional positioning, RTK direction finding, and short message communication capabilities is of great significance.

[0003] Current status of foreign research

[0004] Mayflower, Raytheon, Navsys, Rockwell Collins, and Lockheed Martin in the United States, along with Novatel in Canada, have successfully developed multi-beam anti-jam antennas. Some of these products have been successfully implemented in the Joint Precision Approach and Landing System (JPALS). However, there are few reports of high-precision anti-jam engineering prototypes in practical use. Publicly available literature mentions only Rockwell Collins' DIGAR-300 as supporting JPALS, but it remains uncertain whether this function is supported in anti-jam mode, and its anti-jam capabilities in this mode are unknown. There are also no reports of compatible receivers.

[0005] Current status of domestic research

[0006] While numerous research and education institutions in my country have conducted research on anti-interference technologies, and numerous related publications have been published, there's still a significant gap compared to international standards. Currently, many devices have been equipped with Beidou anti-interference antennas, the vast majority of which utilize power inversion algorithms, with only a few claiming to employ multi-beamforming technology. Numerous specialized technical research projects are underway, primarily focusing on anti-interference algorithm design and signal processing, and the pace of research in anti-interference equipment needs to be accelerated. This research is primarily based on established theories of GPS anti-interference, and numerous research institutions have published technical articles on anti-interference algorithms.

[0007] Domestically, greater emphasis is placed on anti-interference strength, with less consideration given to positioning accuracy after interference mitigation. Only a few platforms have established requirements for pseudorange accuracy after interference mitigation. Some scholars have suggested that optimizing the carrier-to-noise ratio (C / N) as a criterion for system performance is more suitable for high-precision interference mitigation than minimizing output power. In navigation satellite systems, both bit error rate and pseudo-code ranging accuracy are closely related to the integrated signal-to-interference-plus-noise ratio (also known as carrier-to-noise ratio, C / N0), making C / N ratio a more appropriate metric for evaluating system performance.

[0008] Although domestic universities and some manufacturers have published some articles, there has been no public report on a high-precision anti-interference navigation receiving system that meets similar indicators to the US JPALS.

[0009] Furthermore, regarding the development of robust precision differential navigation receivers, most of the research reported in domestic literature focuses on optimizing the threshold parameters of various functional modules in the RTK solution software based on traditional Beidou high-precision receivers, without fully optimizing the entire processing method. Currently, there are no mature engineering applications for achieving interference-resistant, high-precision RTK direction finding in suppressed broadband interference environments.

[0010] Based on this technical background, the present invention studies an anti-interference direction finding and short message communication device based on Beidou satellite array antenna. Summary of the Invention

[0011] In response to the shortcomings of the existing technology, the present invention proposes an anti-interference direction-finding and short message communication device based on the Beidou satellite array antenna. The device includes an anti-interference baseband signal processing module, an RTK precision direction-finding solution module, a navigation information processing module, and a short message communication module, which realizes reliable and accurate Beidou satellite navigation direction-finding and short message data communication in various fields and platforms under complex electromagnetic environments.

[0012] To achieve the above-mentioned object, the present invention provides an anti-interference direction-finding and short message communication device based on a Beidou satellite array antenna, the device comprising a master terminal and a slave terminal; the master terminal is electrically connected to the slave terminal for mutually receiving each other's original satellite observation data: The master terminal and the slave terminal each include a separate Beidou satellite array antenna module, an anti-interference baseband signal processing module, an RTK precision direction finding solution module, and a navigation information processing module. The master terminal also includes a short message communication module. The Beidou satellite array antenna module is used to receive Beidou satellite frequency signals, the anti-interference baseband signal processing module is used to perform baseband processing on the processed Beidou satellite frequency signals to obtain baseband processed signals, the RTK precise direction finding solution module and the navigation information processing module are used to perform calculations on the baseband processed signals to obtain direction finding results and navigation information, respectively, and the short message communication module is used to complete the sending and receiving of short messages.

[0013] The effects of the present invention are: (1) The anti-interference direction-finding and short message communication device based on the Beidou satellite array antenna proposed in the present invention includes an anti-interference baseband signal processing module, an RTK precision direction-finding solution module, a navigation information processing module, and a short message communication module, which realizes reliable and accurate Beidou satellite navigation direction-finding and short message data communication in various fields and platforms under complex electromagnetic environments.

[0014] (2) The present invention proposes an anti-interference direction-finding and short message communication device based on the Beidou satellite array antenna. The passive antenna array is a multi-feed microstrip patch antenna array with an axisymmetric and center-symmetric design, which ensures that the passive antenna array has many feeding points, good antenna gain non-circularity and antenna axial ratio, and higher phase center stability, thereby achieving a good gain radiation pattern and axial ratio radiation pattern.

[0015] (3) The anti-interference direction-finding and short message communication device based on the Beidou satellite array antenna proposed in the present invention comprises a limiter, a first filter and a two-stage series amplifier circuit electrically connected in sequence. The two-stage series amplifier circuit is used to ensure that the entire low-noise amplifier has a gain of 25~35dB, so as to ensure that the total output gain is still more than 20 dB after compensating for the combination and line losses.

[0016] (4) The anti-interference direction-finding and short message communication device based on the Beidou satellite array antenna proposed in this invention, based on the research on fast time-varying interference suppression, breaks through the adaptive anti-interference array antenna signal distortion suppression technology through the anti-interference baseband signal processing module, realizes the reception of satellite navigation signals in a strong electromagnetic interference environment, and effectively suppresses broadband, narrowband, multi-tone, single-tone, sweep frequency, flicker, pulse and other suppression interference.

[0017] (5) The anti-interference direction-finding and short message communication device based on the Beidou satellite array antenna proposed in this invention and the RTK precision direction-finding solution module perform high-precision direction-finding based on carrier phase, with carrier phase distortion less than 15°. It is suitable for anti-interference application scenarios of various carrier platforms such as airborne, vehicle-mounted, missile-mounted, and ship-mounted.

[0018] Other features and advantages of the present invention will be described in detail in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The above and other objects, features and advantages of the present invention will become more apparent through a more detailed description of exemplary embodiments of the present invention with reference to the accompanying drawings, wherein like reference numerals generally represent like components throughout the exemplary embodiments of the present invention.

[0020] Figure 1This is a structural schematic diagram of the anti-interference direction finding and short message communication device based on Beidou satellite array antenna proposed by the present invention.

[0021] Figure 2 This is a structural schematic diagram of the master terminal in the anti-interference direction finding and short message communication device based on the Beidou satellite array antenna proposed by the present invention.

[0022] Figure 3 This is a structural schematic diagram of the integrated processing board in the anti-interference direction-finding and short message communication device based on the Beidou satellite array antenna proposed by the present invention.

[0023] Figure 4 This is a schematic diagram of the algorithm flow of the RTK precise direction finding solution module in the anti-interference direction finding and short message communication device based on the Beidou satellite array antenna proposed by the present invention.

[0024] Figure 5 This is a schematic diagram of the passive antenna array layout in the anti-interference direction finding and short message communication device based on the Beidou satellite array antenna proposed by the present invention.

[0025] Figure 6 This is a schematic diagram of the low-noise amplifier circuit structure in the anti-interference direction-finding and short message communication device based on the Beidou satellite array antenna proposed by the present invention.

[0026] Description of reference numerals: 1-Master, 2-Slave, 3-Integrated Processing Board, 4-Power Interface Board, 5-FPGA, 6-DSP 101- Beidou satellite array antenna module, 102- downconversion module, 103- AD conversion module, 104- anti-interference baseband signal processing module, 105- acquisition unit, 106- tracking unit, 107- RTK precision direction finding solution module, 108- navigation information processing module, 109- short message communication module, 110- SDRAM, 111- DSP bus interface unit, 112- HPI bus interface unit, 113- GPIO interface, 114- indicator light, 115- RTC timing unit, 116- SPI interface, 117- universal serial port controller, 118- SDPRAM, 119- TLC unit; 201-B3 antenna unit, 202-S antenna unit, 203-B1 antenna unit, 204-L antenna unit; 301-limiter, 302-first filter, 303-amplifier circuit; 401 - low noise amplifier, 402 - second filter, 403 - attenuator; 1001-Upgrade and refill RS232 interface cable, 1002-Master and slave RS422 interface cables, 1003-RS232 interface data cable, 1004-Serial port controller RS422 interface cable, 1005-Bidirectional data interface, 1006-TLC unit RS422 interface cable. DETAILED DESCRIPTION

[0027] The preferred embodiments of the present invention will be described in more detail below. Although the preferred embodiments of the present invention are described below, it should be understood that the present invention can be implemented in various forms and should not be limited to the embodiments set forth herein.

[0028] In this disclosure, unless otherwise stated, directional words such as "upper" and "lower" generally refer to the upper and lower positions of the device in normal use. Figure 1 In the drawing orientation, "inside" and "outside" refer to the outline of the device. In addition, the terms "first, second, and third" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features indicated. Therefore, features specified as "first, second, and third" may explicitly or implicitly include one or more of such features. In the description of this disclosure, "plurality" means two or more, unless otherwise explicitly and specifically defined.

[0029] The present invention provides an anti-interference direction finding and short message communication device based on Beidou satellite array antenna, such as Figures 1 to 6 As shown, the device includes a master terminal 1 and a slave terminal 2; the master terminal 1 is electrically connected to the slave terminal 2, and is used to receive each other's original satellite observation data: The master terminal 1 and the slave terminal 2 each include an independent BeiDou satellite array antenna module 101, an anti-interference baseband signal processing module 104, an RTK precision direction finding solution module 107, and a navigation information processing module 108. The master terminal 1 also includes a short message communication module 109. The Beidou satellite array antenna module 101 is used to receive Beidou satellite frequency signals, the anti-interference baseband signal processing module 104 is used to perform baseband processing on the processed Beidou satellite frequency signals to obtain baseband processed signals, the RTK precise direction finding solution module 107 and the navigation information processing module 108 are used to perform calculations on the baseband processed signals to obtain direction finding results and navigation information, respectively, and the short message communication module 109 is used to complete the sending and receiving of short messages.

[0030] According to the present invention, the BeiDou satellite array antenna module 101 is used to receive five B3, B1, and S frequency signals and transmit an L frequency signal; The anti-interference baseband signal processing module 104 is used to perform anti-interference processing, capture and track the five B3 frequency point signals that have been sequentially down-converted and AD-converted, and is used to capture and track the B1 frequency point signal that has been sequentially down-converted and AD-converted; The RTK precision direction finding calculation module 107 is used to perform high-precision direction finding based on the carrier phase on the five B3 and B1 frequency signals that have been captured and tracked to obtain direction finding results; The navigation information processing module 108 is used to process the five captured and tracked B3 and B1 frequency signals to obtain navigation information; The short message communication module 109 is used to process the received S-frequency signal into received short message information, and send the processed short message information to the Beidou satellite array antenna module 101 as an L-frequency signal.

[0031] In the present invention, the anti-interference baseband signal processing module 104, the RTK precision direction finding solution module 107, the navigation information processing module 108 and the short message communication module 109 realize reliable and accurate Beidou satellite navigation direction finding and short message data communication in various fields and platforms under complex electromagnetic environments.

[0032] According to the present invention, the Beidou satellite array antenna module 101 includes a passive antenna array and a multi-channel low noise amplifier circuit; The passive antenna array includes five B3 antenna units 201, a B1 antenna unit 203, an S antenna unit 202 and an L antenna unit 204; The plane where the passive antenna array is located is rectangular; The B1 antenna unit 203 and one B3 antenna unit 201 are stacked and arranged at the center of the rectangle, and the remaining four B3 antenna units 201 are arranged at the four corners of the rectangle, forming a central symmetry; the S antenna unit 202 and the L antenna unit 204 are symmetrically arranged on both sides of any symmetry axis of the rectangle, and are respectively close to a pair of opposite sides of the rectangle; Each of the B3 antenna unit 201, the B1 antenna unit 203, the S antenna unit 202, and the L antenna unit 204 is electrically connected to a low noise amplifier circuit; Each low noise amplifier circuit includes a limiter 301, a first filter 302 and a two-stage amplifier circuit 303 electrically connected in sequence; The parameters of the limiter 301, the first filter 302 and the two-stage series amplifier circuit 303 of each low noise amplifier circuit are the same or different; Each stage of the amplifier circuit 303 includes a low noise amplifier 401, a second filter 402 and an attenuator 403 electrically connected in sequence; The parameters of the low noise amplifier 401 , the second filter 402 and the attenuator 403 of each stage of the amplifier circuit 303 are the same or different; The five B3 antenna units 201 , the B1 antenna unit 203 , the S antenna unit 202 and the L antenna unit 204 are all multi-feed microstrip patch antennas.

[0033] In the present invention, the passive antenna array is a multi-feed microstrip patch antenna array with an axially symmetrical and centrosymmetrical design, which ensures that the passive antenna array has many feeding points, good antenna gain non-circularity and antenna axial ratio, and higher phase center stability, thereby achieving a good gain radiation pattern and axial ratio radiation pattern.

[0034] In the present invention, each low-noise amplifier circuit includes a limiter 301, a first filter 302, and a two-stage series amplifier circuit 303 electrically connected in sequence. The two-stage series amplifier circuit 303 ensures that the entire low-noise amplifier has a gain of 25-35dB, thereby ensuring that the total output gain is still above 20dB after compensating for combining and line losses.

[0035] According to the present invention, the anti-interference baseband signal processing module 104, the RTK precise direction finding solution module 107, and the navigation information processing module 108 are integrated into the comprehensive processing board 3; The integrated processing board 3 further includes a down-conversion module 102 and an AD conversion module 103 , wherein the down-conversion module 102 is electrically connected to the analog signal input port of the AD conversion module 103 ; The down-conversion module 102 is used to down-convert the five B3, B1, and S frequency signals of the Beidou satellite array antenna module 101 received into five B3, B1, and S intermediate frequency analog frequency signals respectively; The AD conversion module 103 is used to convert the five B3, B1, and S intermediate frequency analog frequency point signals into five B3, B1, and S intermediate frequency digital frequency point signals respectively.

[0036] Preferably, the integrated processing board 3 is divided into an FPGA part 5, a DSP part 6 and peripheral modules according to the functional implementation of different modules thereon. The FPGA part 5 is implemented by an FPGA chip, and the DSP part 6 is implemented by a DSP chip. The FPGA part 5 includes an anti-interference baseband signal processing module 104, a capture unit 105 and a tracking unit 106, which are electrically connected in sequence, and an FPGA bus; The input port of the anti-interference baseband signal processing module 104 is electrically connected to the five B3 intermediate frequency digital signal output ports of the AD conversion module 103; The digital signal input port of the capture unit 105 is electrically connected to the B1 intermediate frequency digital signal output port of the AD conversion module 103; The tracking unit 106 is connected to the FPGA bus; The peripheral module includes an indicator light 114 , an RTC timing unit 115 , a power interface board 4 and an SDRAM 110 .

[0037] Preferably, the FPGA part 5 further includes a GPIO interface 113, an SPI interface 116, a universal serial port controller 117, an SDPRAM 118, a TLC unit 119, a DSP bus interface unit 111 and an HPI bus interface unit 112; The bidirectional port of the GPIO interface 113 is electrically connected to the FPGA bus, and the output port is electrically connected to the indicator light 114; The bidirectional port of the SPI interface 116 is electrically connected to the FPGA bus, and the output port is electrically connected to the RTC timing unit 115; The bidirectional ports of the universal serial port controller 117 and the TLC unit 119 are electrically connected to the FPGA bus, and the output ports are electrically connected to the power interface board 4 via the RS422 interface cable 1004 of the serial port controller and the RS422 interface cable 1006 of the TLC unit respectively; The SDPRAM 118 is provided with a bidirectional data interface 1005 .

[0038] According to the present invention, the DSP part 6 includes an RTK precise direction finding solution module 107 and a navigation information processing module 108; One side bidirectional port of the DSP bus interface unit 111 is electrically connected to the FPGA bus, and the other side bidirectional port is electrically connected to the bidirectional port of the navigation information processing module 108; One bidirectional port of the HPI bus interface unit 112 is electrically connected to the FPGA bus, and the other bidirectional port is electrically connected to one bidirectional port of the RTK precision direction finding solution module 107; The other bidirectional port of the RTK precise direction finding solution module 107 is electrically connected to the bidirectional port of the SDRAM 110 .

[0039] According to the present invention, the algorithm flow of the RTK precise direction finding solution module 107 includes the following steps: Step 1: Perform gross error identification and location, clock jump detection, and cycle slip detection on the carrier phases of the five captured and tracked B3 and B1 frequency signals to obtain gross error processed signals. Step 2: Correct and eliminate the gross error processing signal to obtain an error elimination signal; Step 3: The error elimination signal is subjected to adaptive adjustment of the function model and random model, robust Kalman filtering, adjustment of the method for rapid convergence and reliable fixation of the integer ambiguity, calculation of the RTK fixed solution and post-verification residual test to obtain the direction finding result.

[0040] Preferably, the gross error signals obtained by gross error identification and positioning are eliminated; Repair the clock jump signal obtained by clock jump detection; Marking the cycle slip signal obtained by cycle slip detection; If the RTK fixed solution calculation and post-verification residual error test results fail, repeat step 3 until the RTK fixed solution calculation and post-verification residual error test results pass.

[0041] In the present invention, the RTK precision direction finding solution module 107 performs high-precision direction finding based on carrier phase, with carrier phase distortion less than 15°. It is suitable for anti-interference application scenarios of various carrier platforms such as airborne, vehicle-mounted, missile-mounted, and ship-mounted.

[0042] According to the present invention, the power interface board 4 is provided with a short message communication module 109 and a power module; The data port of the short message communication module 109 is electrically connected to the output port of the universal serial port controller 117 or the TLC unit 119, the input port is electrically connected in sequence to the channel decoder, the AD converter, the down-conversion module 102, the receiving filter module, the receiving amplifier module and the S antenna unit 202, and the output port is electrically connected in sequence to the channel encoder, the DA converter, the up-conversion module, the transmitting amplifier module, the transmitting filter module, the transmitting power amplifier module and the L antenna unit 204; The power module is used to provide power supply to all modules and units in the device; The master terminal 1 is electrically connected to the slave terminal 2 via the master-slave RS422 interface cable 1002; The power interface board 4 is connected to the integrated processing board 3 via an RS232 interface data cable 1003; Both the master terminal 1 and the slave terminal 2 include an upgraded and refilled RS232 interface cable 1001 .

[0043] In the present invention, based on the research on fast time-varying interference suppression, through the anti-interference baseband signal processing module 104, a breakthrough is made in the adaptive anti-interference array antenna signal distortion suppression technology, and satellite navigation signal reception is achieved in a strong electromagnetic interference environment, effectively suppressing broadband, narrowband, multi-tone, single-tone, sweep frequency, flicker, pulse and other suppression interference.

[0044] The present invention will be described in more detail below through a specific embodiment.

[0045] Example 1

[0046] like Figures 1 to 6 This embodiment provides an anti-interference direction finding and short message communication device based on a Beidou satellite array antenna. The device includes a master terminal 1 and a slave terminal 2. The master terminal 1 is electrically connected to the slave terminal 2 to receive each other's original satellite observation data. The master terminal 1 and the slave terminal 2 each include an independent BeiDou satellite array antenna module 101, an anti-interference baseband signal processing module 104, an RTK precision direction finding solution module 107, and a navigation information processing module 108. The master terminal 1 also includes a short message communication module 109. The Beidou satellite array antenna module 101 is used to receive Beidou satellite frequency signals, the anti-interference baseband signal processing module 104 is used to perform baseband processing on the processed Beidou satellite frequency signals to obtain baseband processed signals, the RTK precise direction finding solution module 107 and the navigation information processing module 108 are used to perform calculations on the baseband processed signals to obtain direction finding results and navigation information, respectively, and the short message communication module 109 is used to complete the sending and receiving of short message information; The BeiDou satellite array antenna module 101 is used to receive five B3, B1, and S frequency signals and transmit L frequency signals; The anti-interference baseband signal processing module 104 is used to perform anti-interference processing, capture and track the five B3 frequency point signals that have been sequentially down-converted and AD-converted, and is used to capture and track the B1 frequency point signal that has been sequentially down-converted and AD-converted; The RTK precision direction finding calculation module 107 is used to perform high-precision direction finding based on the carrier phase on the five B3 and B1 frequency signals that have been captured and tracked to obtain direction finding results; The navigation information processing module 108 is used to process the five captured and tracked B3 and B1 frequency signals to obtain navigation information; The short message communication module 109 is used to process the received S frequency signal into received short message information, and send the processed short message information to the Beidou satellite array antenna module 101 as an L frequency signal transmission; The BeiDou satellite array antenna module 101 includes a passive antenna array and a multi-channel low-noise amplifier circuit; The passive antenna array includes five B3 antenna units 201, a B1 antenna unit 203, an S antenna unit 202 and an L antenna unit 204; The plane where the passive antenna array is located is rectangular; The B1 antenna unit 203 and one B3 antenna unit 201 are stacked and arranged at the center of the rectangle, and the remaining four B3 antenna units 201 are arranged at the four corners of the rectangle, forming a central symmetry; the S antenna unit 202 and the L antenna unit 204 are symmetrically arranged on both sides of any symmetry axis of the rectangle, and are respectively close to a pair of opposite sides of the rectangle; Each of the B3 antenna unit 201, the B1 antenna unit 203, the S antenna unit 202, and the L antenna unit 204 is electrically connected to a low noise amplifier circuit; Each low noise amplifier circuit includes a limiter 301, a first filter 302 and a two-stage amplifier circuit 303 electrically connected in sequence; The parameters of the limiter 301, the first filter 302 and the two-stage series amplifier circuit 303 of each low noise amplifier circuit are the same or different; Each stage of the amplifier circuit 303 includes a low noise amplifier 401, a second filter 402 and an attenuator 403 electrically connected in sequence; The parameters of the low noise amplifier 401 , the second filter 402 and the attenuator 403 of each stage of the amplifier circuit 303 are the same or different; The five B3 antenna units 201, the B1 antenna unit 203, the S antenna unit 202, and the L antenna unit 204 are all multi-feed microstrip patch antennas; The anti-interference baseband signal processing module 104, the RTK precision direction finding solution module 107, and the navigation information processing module 108 are integrated into the comprehensive processing board 3; The integrated processing board 3 further includes a down-conversion module 102 and an AD conversion module 103 , wherein the down-conversion module 102 is electrically connected to the analog signal input port of the AD conversion module 103 ; The down-conversion module 102 is used to down-convert the five B3, B1, and S frequency signals of the Beidou satellite array antenna module 101 received into five B3, B1, and S intermediate frequency analog frequency signals respectively; The AD conversion module 103 is used to convert the five B3, B1, and S intermediate frequency analog frequency signals into five B3, B1, and S intermediate frequency digital frequency signals respectively; The integrated processing board 3 is divided into an FPGA part 5, a DSP part 6 and peripheral modules according to the functional implementation of different modules thereon. The FPGA part 5 is implemented by an FPGA chip, and the DSP part 6 is implemented by a DSP chip. The FPGA part 5 includes an anti-interference baseband signal processing module 104, a capture unit 105 and a tracking unit 106, which are electrically connected in sequence, and an FPGA bus; The input port of the anti-interference baseband signal processing module 104 is electrically connected to the five B3 intermediate frequency digital signal output ports of the AD conversion module 103; The digital signal input port of the capture unit 105 is electrically connected to the B1 intermediate frequency digital signal output port of the AD conversion module 103; The tracking unit 106 is connected to the FPGA bus; The peripheral module includes an indicator light 114, an RTC timing unit 115, a power interface board 4 and an SDRAM 110; The FPGA part 5 also includes a GPIO interface 113, an SPI interface 116, a universal serial port controller 117, an SDPRAM 118, a TLC unit 119, a DSP bus interface unit 111 and an HPI bus interface unit 112; The bidirectional port of the GPIO interface 113 is electrically connected to the FPGA bus, and the output port is electrically connected to the indicator light 114; The bidirectional port of the SPI interface 116 is electrically connected to the FPGA bus, and the output port is electrically connected to the RTC timing unit 115; The bidirectional ports of the universal serial port controller 117 and the TLC unit 119 are electrically connected to the FPGA bus, and the output ports are electrically connected to the power interface board 4 via the RS422 interface cable 1004 of the serial port controller and the RS422 interface cable 1006 of the TLC unit respectively; The SDPRAM 118 is provided with a bidirectional data interface 1005; The DSP part 6 includes an RTK precise direction finding solution module 107 and a navigation information processing module 108; One side bidirectional port of the DSP bus interface unit 111 is electrically connected to the FPGA bus, and the other side bidirectional port is electrically connected to the bidirectional port of the navigation information processing module 108; One bidirectional port of the HPI bus interface unit 112 is electrically connected to the FPGA bus, and the other bidirectional port is electrically connected to one bidirectional port of the RTK precision direction finding solution module 107; The other side bidirectional port of the RTK precision direction finding solution module 107 is electrically connected to the bidirectional port of the SDRAM 110; The algorithm flow of the RTK precision direction finding solution module 107 includes the following steps: Step 1: Perform gross error identification and location, clock jump detection, and cycle slip detection on the carrier phases of the five captured and tracked B3 and B1 frequency signals to obtain gross error processed signals. Step 2: Correct and eliminate the gross error processing signal to obtain an error elimination signal; Step 3: The error elimination signal is subjected to adaptive adjustment of the function model and random model, robust Kalman filtering, adjustment of the method for rapid convergence and reliable fixation of the integer ambiguity, calculation of the RTK fixed solution and post-test residual error test to obtain the direction finding result. The gross error signals obtained by gross error identification and positioning are eliminated; Repair the clock jump signal obtained by clock jump detection; Marking the cycle slip signal obtained by cycle slip detection; If the RTK fixed solution calculation and post-verification residual error test results fail, repeat step 3 until the RTK fixed solution calculation and post-verification residual error test results pass. The power interface board 4 is provided with a short message communication module 109 and a power module; The data port of the short message communication module 109 is electrically connected to the output port of the universal serial port controller 117 or the TLC unit 119, the input port is electrically connected in sequence to the channel decoder, the AD converter, the down-conversion module 102, the receiving filter module, the receiving amplifier module and the S antenna unit 202, and the output port is electrically connected in sequence to the channel encoder, the DA converter, the up-conversion module, the transmitting amplifier module, the transmitting filter module, the transmitting power amplifier module and the L antenna unit 204; The power module is used to provide power supply to all modules and units in the device; The master terminal 1 is electrically connected to the slave terminal 2 via the master-slave RS422 interface cable 1002; The power interface board 4 is connected to the integrated processing board 3 via an RS232 interface data cable 1003; Both the master terminal 1 and the slave terminal 2 include an upgraded and refilled RS232 interface cable 1001 .

[0047] The device in this embodiment includes an anti-interference baseband signal processing module 104, an RTK precision direction finding solution module 107, a navigation information processing module 108, and a short message communication module 109, which realizes reliable and accurate Beidou satellite navigation direction finding and short message data communication in various fields and platforms under complex electromagnetic environments.

[0048] While various embodiments of the present invention have been described above, the above description is intended to be illustrative, not exhaustive, and not limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments.

Claims

1. Anti-interference direction finding and short message communication device based on Beidou satellite array antenna, characterized in that: The device includes a master terminal and a slave terminal; the master terminal is electrically connected to the slave terminal for receiving each other's original satellite observation data. The master terminal and the slave terminal each include a separate Beidou satellite array antenna module, an anti-interference baseband signal processing module, an RTK precision direction finding solution module, and a navigation information processing module. The master terminal also includes a short message communication module. The Beidou satellite array antenna module is used to receive Beidou satellite frequency signals, the anti-interference baseband signal processing module is used to perform baseband processing on the processed Beidou satellite frequency signals to obtain baseband processed signals, the RTK precise direction finding solution module and the navigation information processing module are used to perform calculations on the baseband processed signals to obtain direction finding results and navigation information, respectively, and the short message communication module is used to complete the sending and receiving of short message information.

2. The device according to claim 1, characterized in that The Beidou satellite array antenna module is used to receive 5 B3, B1, and S frequency signals and transmit L frequency signals; The anti-interference baseband signal processing module is used to perform anti-interference processing, capture and track the five B3 frequency point signals that have been sequentially down-converted and AD-converted, and is used to capture and track the B1 frequency point signal that has been sequentially down-converted and AD-converted; The RTK precision direction finding calculation module is used to perform high-precision direction finding based on the carrier phase on the five B3 and B1 frequency signals that have been captured and tracked to obtain direction finding results; The navigation information processing module is used to process the five captured and tracked B3 and B1 frequency signals to obtain navigation information; The short message communication module is used to process the received S frequency signal to obtain short message information, and send the processed short message information to the Beidou satellite array antenna module as the L frequency signal for transmission.

3. The device according to claim 2, characterized in that The Beidou satellite array antenna module includes a passive antenna array and a multi-channel low-noise amplifier circuit; The passive antenna array includes five B3 antenna units, a B1 antenna unit, an S antenna unit and an L antenna unit; The plane where the passive antenna array is located is rectangular; The B1 antenna unit and one B3 antenna unit are stacked and arranged at the center of the rectangle, and the remaining four B3 antenna units are respectively arranged at the four corners of the rectangle, and form central symmetry; the S antenna unit and the L antenna unit are symmetrically arranged on both sides of any symmetry axis of the rectangle, and are respectively close to a pair of opposite sides of the rectangle; Each of the B3 antenna unit, the B1 antenna unit, the S antenna unit, and the L antenna unit is electrically connected to a low noise amplifier circuit; Each low noise amplifier circuit includes a limiter, a first filter and two-stage amplifier circuits connected in series electrically in sequence; The parameters of the limiter, the first filter and the two-stage series amplifier circuit of each low-noise amplifier circuit are the same or different; Each stage of the amplifier circuit includes a low noise amplifier, a second filter and an attenuator electrically connected in sequence; The parameters of the low noise amplifier, the second filter and the attenuator of each stage of the amplifier circuit are the same or different; The five B3 antenna units, the B1 antenna unit, the S antenna unit and the L antenna unit are all multi-feed microstrip patch antennas.

4. The device according to claim 2, characterized in that The anti-interference baseband signal processing module, RTK precision direction finding solution module, and navigation information processing module are integrated into the comprehensive processing board; The integrated processing board further comprises a down-conversion module and an AD conversion module, wherein the down-conversion module is electrically connected to the analog signal input port of the AD conversion module; The down-conversion module is used to down-convert the five B3, B1, and S frequency signals of Beidou received by the Beidou satellite array antenna module into five B3, B1, and S intermediate frequency analog frequency signals respectively; The AD conversion module is used to convert the five B3, B1, and S intermediate frequency analog frequency point signals into five B3, B1, and S intermediate frequency digital frequency point signals respectively.

5. The device according to claim 4, characterized in that The integrated processing board is divided into an FPGA part, a DSP part and peripheral modules according to the functional implementation of different modules thereon, the FPGA part is implemented by an FPGA chip, and the DSP part is implemented by a DSP chip; The FPGA part includes an anti-interference baseband signal processing module, a capture unit and a tracking unit, and an FPGA bus that are electrically connected in sequence; The input port of the anti-interference baseband signal processing module is electrically connected to the five B3 intermediate frequency digital signal output ports of the AD conversion module; The digital signal input port of the capture unit is electrically connected to the B1 intermediate frequency digital signal output port of the AD conversion module; The tracking unit is connected to the FPGA bus; The peripheral module includes an indicator light, an RTC timing unit, a power interface board and an SDRAM.

6. The device according to claim 5, characterized in that The FPGA part also includes a GPIO interface, an SPI interface, a universal serial port controller, an SDPRAM, a TLC unit, a DSP bus interface unit and an HPI bus interface unit; The bidirectional port of the GPIO interface is electrically connected to the FPGA bus, and the output port is electrically connected to the indicator light; The bidirectional port of the SPI interface is electrically connected to the FPGA bus, and the output port is electrically connected to the RTC timing unit; The bidirectional ports of the universal serial port controller and the TLC unit are electrically connected to the FPGA bus, and the output ports are electrically connected to the power interface board through the RS422 interface cable of the serial port controller and the RS422 interface cable of the TLC unit respectively; The SDPRAM is provided with a bidirectional data interface.

7. The device according to claim 6, characterized in that The DSP part includes the RTK precise direction finding solution module and the navigation information processing module; The bidirectional port on one side of the DSP bus interface unit is electrically connected to the FPGA bus, and the bidirectional port on the other side is electrically connected to the bidirectional port of the navigation information processing module; One side bidirectional port of the HPI bus interface unit is electrically connected to the FPGA bus, and the other side bidirectional port is electrically connected to one side bidirectional port of the RTK precision direction finding and solving module; The bidirectional port on the other side of the RTK precise direction finding and solving module is electrically connected to the bidirectional port of the SDRAM.

8. The device according to claim 7, characterized in that The algorithm flow of the RTK precision direction finding solution module includes the following steps: Step 1: Perform gross error identification and location, clock slip detection, and cycle slip detection on the carrier phase observations of the five captured and tracked B3 and B1 frequency signals to obtain gross error processed signals. Step 2: performing error correction and elimination on the gross error processed signal to obtain an error eliminated signal; Step 3: The error elimination signal is subjected to adaptive adjustment of the function model and random model, robust Kalman filtering, adjustment of the method for rapid convergence and reliable fixation of the integer ambiguity, calculation of the RTK fixed solution and post-verification residual test to obtain the direction finding result.

9. The device according to claim 8, characterized in that Eliminating the gross error signals obtained by the gross error identification and positioning; Repairing the clock jump signal obtained by the clock jump detection; Marking the cycle slip signal obtained by the cycle slip detection; If the RTK fixed solution calculation and the post-test residual error test result fail to meet the requirements, repeat step 3 until the RTK fixed solution calculation and the post-test residual error test result meet the requirements.

10. The device according to claim 9, characterized in that The power interface board is provided with a short message communication module and a power module; The data port of the short message communication module is electrically connected to the output port of the universal serial port controller or the TLC unit, the input port is electrically connected to the channel decoder, the AD converter, the down-conversion module, the receiving filter module, the receiving amplifier module and the S antenna unit in sequence, and the output port is electrically connected to the channel encoder, the DA converter, the up-conversion module, the transmitting amplifier module, the transmitting filter module, the transmitting power amplifier module and the L antenna unit in sequence; The power supply module is used to provide power supply to all modules and units in the device; The master terminal is electrically connected to the slave terminal via a master-slave RS422 interface cable; The power interface board is connected to the integrated processing board via an RS232 interface data cable; The master and slave terminals both include upgraded RS232 interface cables.

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