Unmanned aerial vehicle interference monitoring and direction finding device

Abstract

The utility model belongs to the technical field of monitoring and direction-finding devices, and relates to an unmanned aerial vehicle interference monitoring and direction-finding device, which comprises a monitoring and direction-finding antenna, a monitoring and direction-finding host and a ground control terminal, and is characterized in that the monitoring and direction-finding host comprises a three-channel receiving channel module, an intermediate frequency signal processing board, a single board computer and wireless data transmission equipment; the ground control terminal is loaded with navigation interference monitoring direction-finding software, the three-channel receiving channel module is connected with the intermediate frequency signal processing board, the intermediate frequency signal processing board is connected with the single board computer, the single chip microcomputer is connected with the wireless data transmission equipment, the monitoring direction-finding antenna is connected with the three-channel receiving channel module of the monitoring direction-finding host computer, and the monitoring direction-finding host computer is connected with the wireless data transmission equipment. The wireless data transmission device is shared with a wireless data transmission device of the unmanned aerial vehicle, and the monitoring direction-finding host is connected with the ground control terminal through the wireless data transmission device; the system is good in electromagnetic compatibility, can be quickly assembled and disassembled, is low in power consumption of the whole machine, and meets the requirements of various task scenes.

Description

Technical Field

[0001] The utility model belongs to a monitoring and direction-finding device, and relates to an unmanned aerial vehicle interference monitoring and direction-finding device. Background Technique

[0002] In their work, the radio management department mainly relies on ground two-dimensional monitoring to identify interference sources, using monitoring vehicles or handheld devices for a carpet search, mostly relying on the experience of technicians. The radio management department is responsible for the radio management of the entire frequency band in the whole country and the whole industry, and it is difficult to carry out timely and efficient investigation work for radio interference. Therefore, radio interference is difficult to be investigated and punished in a timely and efficient manner.

[0003] At present, the DF02-01 device developed by a research institute under China National Electronics Corporation has achieved the function of ultra-short wave direction finding, can complete high-speed direction finding, and can realize the monitoring and analysis of various signals. In particular, good monitoring effects have been achieved for mutation signals. Since the complex ground environment will increase the difficulty of interference source troubleshooting work, the research on airborne radio monitoring has been carried out. The Beijing Dongfang Bote Radio Spectrum Technology Research Institute under the State Radio Monitoring Center has developed the DFA-I radio monitoring system for civil aviation, which can carry out monitoring and analysis for the civil aviation VHF band. However, the DFA-I radio monitoring system is only for the civil aviation VHF band and cannot monitor and analyze other bands. Fan Zhenxiong et al. from the Beijing Monitoring Station of the State Radio Monitoring Center have developed a positioning system for illegal radio stations, using an unmanned aerial vehicle (UAV) equipped with a radio direction finding device to locate illegal radio stations in real time through flight path planning. CN105403855A discloses a monitoring and direction finding system based on an aircraft-mounted direction finding device, including a rotorcraft, a flight remote controller, a monitoring and direction finding device, and a monitoring and direction finding terminal. The flight remote controller is used for remotely wirelessly controlling the rotorcraft. The monitoring and direction finding device is mounted on the rotorcraft. The monitoring and direction finding device is connected to the monitoring and direction finding terminal through wireless WIFI. The monitoring and direction finding device includes an electronic compass, a direction finding antenna, a receiver, an X86 processing board, a WIFI module, and a WIFI omnidirectional antenna. The output end of the electronic compass is connected to the X86 processing board. The output end of the direction finding antenna is connected to the receiver. The receiver is connected to the X86 processing board. The X86 processing board is connected to the WIFI module. The WIFI module communicates wirelessly with the monitoring and direction finding terminal through the WIFI omnidirectional antenna. CN210427811U discloses an airborne direction finding and positioning device, a direction finding and positioning terminal, an unmanned aerial vehicle, and a direction finding and positioning system. The airborne direction finding and positioning device is configured to be detachably mounted on the unmanned aerial vehicle and includes: a signal acquisition module for acquiring radio signals in the flight area of the unmanned aerial vehicle; a processor connected to the signal acquisition module for processing the acquired radio signals to form radio data information; and a wireless communication module connected to the processor and performing wireless communication with the direction finding and positioning terminal on the monitoring side to transmit and receive data information, where the data information includes the radio data information. However, the existing monitoring and direction finding devices recorded in these have poor electromagnetic compatibility, are not convenient for rapid loading and unloading, and have relatively high power consumption. Summary of the Invention

[0004] The purpose of the present utility model is to overcome the shortcomings existing in the prior art, and to design and provide an unmanned aerial vehicle (UAV)-borne interference monitoring and direction-finding device, which can meet different requirements such as signal search and detection, positioning and analysis, measure and identify signals such as data links, TACAN, BOC, 4G, etc., realize the optimal monitoring ability for key interference signals, and can be carried on the UAV, and is tightly coupled with other devices on the UAV in terms of layout, information transmission, electromagnetic compatibility, etc.

[0005] To achieve the above purpose, the present utility model is realized through the following technical solutions:

[0006] The present utility model provides an unmanned aerial vehicle (UAV)-borne interference monitoring and direction-finding device. The UAV-borne interference monitoring and direction-finding device is carried on the UAV, and includes a monitoring and direction-finding antenna, a monitoring and direction-finding host, and a ground control terminal. The monitoring and direction-finding antenna includes a monitoring and direction-finding antenna array, a switch, and an electronic compass. The monitoring and direction-finding antenna array, the switch, and the electronic compass are installed in an antenna radome; the monitoring and direction-finding host includes a three-channel receiving channel module, an intermediate frequency signal processing board, a single board computer, and a wireless data transmission device. The ground control terminal is loaded with navigation interference monitoring and direction-finding software. The three-channel receiving channel module is connected to the intermediate frequency signal processing board, the intermediate frequency signal processing board is connected to the single board computer, the single board computer is connected to the wireless data transmission device, the monitoring and direction-finding antenna is connected to the three-channel receiving channel module of the monitoring and direction-finding host, the wireless data transmission device is shared with the wireless data transmission device of the UAV, and the monitoring and direction-finding host is connected to the ground control terminal through the wireless data transmission device.

[0007] As a further technical solution of the present utility model, the monitoring and direction-finding antenna array adopts a five-element monitoring and direction-finding antenna array or a nine-element monitoring and direction-finding antenna array. The aperture of the antenna array is 227 mm. The antennas in the antenna array are active dipole antennas, and the internal power supply is DC + 5V, and the current is 80 mA.

[0008] As a further technical solution of the present utility model, the switch adopts a five-selection-three switch.

[0009] As a further technical solution of the present utility model, the electronic compass adopts an RS232 interface, and its baud rate is 9600.

[0010] As a further technical solution of the present utility model, the monitoring and direction-finding antenna is installed on the UAV through a fixed bracket. The fixed bracket is composed of a fixed part and a movable part. The fixed part is fixedly installed at the bottom of the belly of the UAV. There are mating blind plug connectors at the connection between the fixed part and the movable part. A mounting and dismounting nut is installed on the side of the movable part. The movable part is connected to the fixed part through the blind plug connector and the mounting and dismounting nut.

[0011] As a further technical solution of the present utility model, the three-channel receiving channel module includes a local oscillator unit, a channel unit, and a calibration / power control unit. The calibration / power control unit is respectively connected to the local oscillator unit and the three channel units. Each of the three channel units includes a low-noise amplifier (LNA), a filter, and an intermediate-frequency filter. A frequency synthesizer is provided between the filter and the intermediate-frequency filter, and the three channel units share one frequency synthesizer.

[0012] As a further technical solution of the present utility model, the intermediate-frequency signal processing board includes an FPGA chip, an analog-to-digital converter (high-speed AD), a 102.4M high-precision clock, an on-board FLASH, a synchronous dynamic random access memory (SDRAM), a GPS positioning unit, a broadband power supply, and a 100M Ethernet interface. The FPGA chip is respectively connected to the analog-to-digital converter (high-speed AD), the 102.4M high-precision clock, the on-board FLASH, the synchronous dynamic random access memory (SDRAM), and the GPS positioning unit. The broadband power supply provides power for each component of the intermediate-frequency signal processing board. An analog interface is arranged on the left side of the intermediate-frequency signal processing board, and a digital interface is arranged on the right side, which is convenient for encapsulation and reduces digital-to-analog interference.

[0013] As a further technical solution of the present utility model, the three-channel receiving channel module adopts a superheterodyne double-conversion scheme to convert the antenna signal into an intermediate frequency of 76.8 MHz (bandwidth 40 MHz, 500 kHz) for subsequent processing. The FPGA chip of the intermediate-frequency signal processing board completes the spectrum analysis and signal recognition functions of the short-wave intermediate-frequency signal; the CPU part of the single-board computer completes the control of the internal modules of the receiver and the transfer of the information interface between the receiver and the operation terminal.

[0014] As a further technical solution of the present utility model, the monitoring and direction-finding host is installed in the main chassis. The upper cover of the main chassis covers the lower chassis. A rubber sealing ring is provided at the connection between the lower chassis and the upper cover to make the upper cover and the lower chassis be hermetically connected; the lower cover is installed at the bottom of the lower chassis, and a digital board, a single-board computer, a receiver, and a power module are installed on the lower cover. The digital board, the single-board computer, the receiver, and the power module are connected according to the general electrical principles; the upper cover adopts a detachable cover plate, which is convenient for equipment installation and maintenance; various connectors are provided on the upper cover for easy operation, and the main chassis is placed in the payload compartment of the unmanned aerial vehicle.

[0015] Compared with the prior art, the present utility model fully considers the weight, power consumption, capacity of the unmanned aerial vehicle platform, electromagnetic compatibility requirements, and quick installation and disassembly requirements, ensuring the reliability and safety of the device. Specifically, it has the following advantages:

[0016] (1) Good electromagnetic compatibility. It fully considers the mutual influence between the interference monitoring and direction-finding antenna, the data transmission device, and the landing gear of the unmanned aerial vehicle, and reasonably plans the structural layout and feeder connection to ensure the application efficiency;

[0017] (2) Quick loading and disassembly. The UAV cabin has three compartments. The front and rear compartments are for UAV equipment, and the middle compartment is the payload compartment. The monitoring and direction-finding host is installed in the payload compartment and is equipped with shock pads. It is designed for quick installation. After the equipment is placed, connect the various cables, which is convenient for individual soldiers to operate. The antenna is installed under the lower part of the UAV belly. The mounting plate is made of carbon fiber board and uses a composite joint, which is convenient for quick installation and disassembly.

[0018] (3) Low power consumption. On the UAV platform, in order to ensure continuous monitoring time, low-power design must be carried out to ensure effectiveness. The power consumption of the monitoring and direction-finding host of this utility model is about 50W, and the power consumption of the monitoring and direction-finding antenna is about 15W. The three-channel receiving channel module, intermediate frequency signal processing board, and single-board computer of the monitoring and direction-finding host are all powered by low voltage, so as to ensure the low power consumption of the whole machine.

[0019] (4) Integrated design of detection, control, and measurement. Adopting a dual-channel scheme, it can simultaneously complete the search and control tasks, or the two channels can complete the direction-finding task, realizing the integrated design of detection, control, and direction-finding functions, enhancing the processing ability of interference signals, and greatly improving the use efficiency of the equipment.

[0020] (5) Coordinated operation of wideband and narrowband. Adopting a design scheme with coexistence of wideband and narrowband, it can complete the rapid search for wideband large signals through the wideband mode, or complete the refined search, control, and direction-finding of narrowband small signals through the narrowband mode, improving the processing ability of interference signals.

[0021] (6) Compatible operation of multiple direction-finding methods. Adopting the phase-correlated interferometer to achieve rapid and high-precision direction-finding, and adopting the spatial spectrum estimation direction-finding technology to achieve direction-finding of multiple co-frequency targets, meeting the requirements of various task scenarios. Brief Description of the Drawings

[0022] Figure 1 It is a schematic diagram of the structural principle of the UAV-borne interference monitoring and direction-finding device of this utility model carried on the UAV.

[0023] Figure 2 It is a schematic diagram of the structural principle of the UAV-borne interference monitoring and direction-finding device of this utility model.

[0024] Figure 3 It is a working principle diagram of the monitoring and direction-finding antenna array of this utility model.

[0025] Figure 4 It is a structural block diagram of the monitoring and direction-finding host of this utility model.

[0026] Figure 5 It is a structural block diagram of the three-channel receiving channel module of this utility model.

[0027] Figure 6This is the block diagram of the working principle of the three-channel receiving channel module of the present utility model.

[0028] Figure 7 This is the index allocation diagram of the three-channel receiving channel module of the present utility model.

[0029] Figure 8 This is the structure diagram of the intermediate frequency signal processing board of the present utility model.

[0030] Figure 9 This is the structure diagram of the fixed bracket of the present utility model.

[0031] Figure 10 This is the structure diagram of the main body box of the present utility model.

[0032] Figure 11 This is the schematic diagram of the structural principle of the monitoring and direction-finding antenna of the present utility model. Detailed implementation manners

[0033] The present utility model will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0034] Embodiment 1:

[0035] As Figure 1 and 2 shown, this embodiment provides an airborne interference monitoring and direction-finding device for unmanned aerial vehicles. The airborne interference monitoring and direction-finding device is carried on an unmanned aerial vehicle and includes a monitoring and direction-finding antenna, a monitoring and direction-finding host, and a ground control terminal. The monitoring and direction-finding antenna includes a monitoring and direction-finding antenna array 9, a switch 10, and an electronic compass 11. The monitoring and direction-finding antenna array 9, the switch 10, and the electronic compass 11 are installed in an antenna radome 12 after being connected according to general electrical principles; the monitoring and direction-finding host includes a three-channel receiving channel module, an intermediate frequency signal processing board, a single-board computer, and a wireless data transmission device. The ground control terminal is loaded with navigation interference monitoring and direction-finding software, and the navigation interference monitoring and direction-finding software is software for existing publicly disclosed airborne interference monitoring and direction-finding devices; the three-channel receiving channel module is connected to the intermediate frequency signal processing board, the intermediate frequency signal processing board is connected to the single-board computer, the single-chip microcomputer is connected to the wireless data transmission device, the monitoring and direction-finding antenna is connected to the three-channel receiving channel module of the monitoring and direction-finding host, the wireless data transmission device is shared with the wireless data transmission device of the unmanned aerial vehicle, and the monitoring and direction-finding host is connected to the ground control terminal through the wireless data transmission device.

[0036] As Figure 3 shown, the monitoring and direction-finding antenna array is a single-layer five-element antenna array, the aperture of the antenna array is 227 mm, the antennas in the antenna array are active dipole antennas, the internal power supply is DC + 5V, and the current is 80 mA; the switch 10 is a five-selection-three switch; the electronic compass uses an RS232 interface, and its baud rate is 9600.

[0037] As Figure 9 shown, the monitoring and direction-finding antenna is mounted on the UAV through a fixed bracket. The fixed bracket consists of two parts: a fixed part 13 and a movable part 14. The fixed part 13 is fixedly installed at the bottom of the belly of the UAV. There are mating blind plug connectors 15 at the connection between the fixed part 13 and the movable part 14. A mounting / demounting nut 16 is installed on the side of the movable part 14. The movable part 14 is connected to the fixed part 13 through the blind plug connectors 15 and the mounting / demounting nut 16.

[0038] As Figures 5 - 7 shown, the three-channel receiving channel module includes a local oscillator unit, a channel unit, and a calibration / power control unit. The calibration / power control unit is respectively connected to the local oscillator unit and the three channel units. Each of the three channel units includes a low-noise amplifier (LNA), a filter, and an intermediate-frequency filter. A frequency synthesizer is provided between the filter and the intermediate-frequency filter. The three channel units share one frequency synthesizer; The intermediate-frequency signal processing board includes an FPGA chip, an analog-to-digital converter (high-speed AD), a 102.4M high-precision clock, an on-board FLASH, a synchronous dynamic random access memory (SDRAM), a GPS positioning unit, a broadband power supply, and a 100M Ethernet interface. The FPGA chip is respectively connected to the analog-to-digital converter (high-speed AD), the 102.4M high-precision clock, the on-board FLASH, the synchronous dynamic random access memory (SDRAM), and the GPS positioning unit. The broadband power supply provides power for each component of the intermediate-frequency signal processing board. An analog interface is arranged on the left side of the intermediate-frequency signal processing board, and a digital interface is arranged on the right side, which is convenient for encapsulation and reduces digital-to-analog interference; The three-channel receiving channel module uses a superheterodyne double-conversion scheme to convert the antenna signal to an intermediate frequency of 76.8 MHz (bandwidth 40 MHz, 500 kHz) for subsequent processing. The FPGA chip of the intermediate-frequency signal processing board completes the spectrum analysis and signal recognition functions of the short-wave intermediate-frequency signal; The CPU part of the single-board computer completes the control of the internal modules of the receiver unit and the transfer of the information interface between the receiver unit and the operation terminal.

[0039] As Figure 10 shown, the monitoring and direction-finding host is installed in the main chassis. The upper cover 1 of the main chassis covers the lower chassis 3. There is a rubber sealing ring 2 at the connection between the lower chassis 3 and the upper cover 1, so that the upper cover 1 is hermetically connected to the lower chassis 3; The lower cover 8 is installed at the bottom of the lower chassis 3. A digital board 4, a single-board computer 5, a receiver 6, and a power module 7 are installed on the lower cover 3. The digital board 4, the single-board computer 5, the receiver 6, and the power module 7 are connected according to the general electrical principles; The upper cover 1 is a detachable cover plate, which is convenient for equipment installation and maintenance; Each joint is provided on the upper cover 2 for easy operation. The main chassis is placed in the payload compartment of the UAV.

[0040] This embodiment mainly realizes the following functions:

[0041] The target comprehensive recognition function utilizes the collaborative information obtained by each sensor. Through the association and fusion of multi-sensor multi-source information, information complementarity is achieved to complete the type judgment, attribute recognition, and state tracking of electromagnetic targets, etc. The key to comprehensive recognition is the precise measurement of target features and the sorting of communication signal types such as data links, TACAN, civilian broadcasts, and mobile communications. The recognition and sorting of civilian broadcast and mobile communication signals are based on basic carrier frequencies and modulation styles. The modulation styles of data link signals and TACAN signals are important features of the signals. According to the analysis of the characteristics of the data link, the modulation styles to be recognized are signals such as MSK (Link-16) and AM (TACAN). For different types of modulation signals, the frequency-domain characteristics are not exactly the same. The modulation signal is a frequency modulation signal, and the frequency modulation signal belongs to constant envelope modulation, with a constant signal envelope. The envelope of the amplitude modulation signal changes. Therefore, AM, SSB, and several other constant envelope signals can be distinguished according to the change of the envelope. FM signals and FSK signals can be distinguished by their frequency-domain characteristics. Two spectral peaks can be observed in the spectrum and square spectrum of the FSK signal, while the spectrum of the FM signal will change differently according to the modulation signal. The two signals can be recognized by identifying the number of spectral peaks and according to the obtained results. The SPWVD time-frequency analysis method is selected to estimate the frequency hopping parameters of the Link16 data link signal.

[0042] The function of direction finding for multi-signals with the same frequency directly uses the data obtained by sampling the spatial electromagnetic field by each array element. According to various existing parameter estimation criteria and algorithms for direction finding, the resolution of the array breaks through the traditional Rayleigh limit. From then on, signal processing means can be used to improve the array signal resolution instead of simply increasing the array aperture. The MUSIC algorithm utilizes the orthogonality between the signal subspace and the noise subspace to construct a spatial spectrum function. By searching for spectral peaks, the DOA of the signal is detected. This type of signal subspace method not only has a relatively clear physical concept but also can obtain an asymptotically unbiased estimator when the signals are not completely correlated. Above the signal-to-noise ratio threshold, the variance of the estimator is close to the variance of the maximum likelihood estimator, and it has good resolution performance for incoherent signals in a small array.

[0043] BOC recognition function. The essence of binary offset carrier (BOC) modulation is to multiply a sub-carrier after BPSK modulation. Multiplying a carrier in the time domain is equivalent to shifting the power spectrum of BPSK to the left and right sub-carrier frequencies in the frequency domain. By multiplying sub-carriers with different frequencies, multiple GNSS systems and various satellite signals can be made compatible within a limited frequency band. Therefore, the recognition of BOC signals mainly involves distinguishing them from BPSK. The baseband signal of BOC signals consists of three parts, including the navigation message, spreading pseudo-code in traditional BPSK modulation, and a new component sub-carrier. BOC signals are extended from BPSK, and signal recognition mainly focuses on differentiating from BPSK, mainly based on characteristics such as power spectral density and autocorrelation characteristics.

[0044] Weak spread-spectrum signal recognition function. Anti-jamming recognition of weak spread-spectrum signals generally uses temporal pulse accumulation. Mainly by increasing the observation time, the energy of the received signal is accumulated significantly, effectively improving the detection performance. However, due to the long-time detection of weak targets, during the accumulation process, the target may have crossed multiple range cells. Currently, using traditional methods for long-time coherent accumulation of signals will also encounter many problems in engineering, resulting in a reduced detection ability for weak signals. Therefore, how to effectively accumulate the target signal during an observation time of up to seconds, accumulate the echo energy to the greatest extent to improve the detection performance. To improve the detection ability for weak targets moving at a constant speed, this embodiment uses the DSSS_2DPSK-RFT algorithm for accumulating and detecting weak targets moving at a constant speed. Based on the RFT algorithm, the DSSS_2DPSK-RFT algorithm for accumulating and detecting weak targets moving at a constant speed can compensate for range and Doppler walks simultaneously, improve the echo accumulation gain, better suppress noise, greatly improve the signal-to-noise ratio of moving targets, and significantly improve the radar's performance in accumulating and detecting weak targets moving at a constant speed. In addition, to achieve radar-communication integration using OFDM signals, the communication modulation information will affect the ambiguity function of the integrated waveform. Considering pre-modulating the communication information to make it have excellent aperiodic autocorrelation and cross-correlation characteristics, uniformly pre-modulate the communication information between different OFDM symbols in the same transmitted pulse to solve the problem that the ambiguity function of the integrated waveform is sensitive to communication modulation information. Transform the OFDM signal and use it as a radar detection signal, carrying communication symbols at the same time. After being transmitted by the transmitter, target detection is performed, which is mainly based on the integrated signal design of communication signals. Considering using the frequency-domain characteristics of OFDM signals, process the radar ranging signal through Fourier transform, use the IAR algorithm to correct the range migration of the target echo by means of coordinate rotation transformation, perform energy accumulation based on one-dimensional search in the velocity dimension, and analyze the radar detection performance.

[0045] Embodiment 2:

[0046] In this embodiment, the UAV-borne interference monitoring and direction-finding device described in Embodiment 1 is mounted on a UAV. The application scenario is electromagnetic environment monitoring and signal template establishment, that is, through panoramic scanning, the electromagnetic environment of the current area is preliminarily collected to establish an electromagnetic environment signal template for the current area. In this application scenario, the system will generate FFT spectrum intermediate data, signal sorting data, and IQ sample data. Assume:

[0047] (1) The panoramic scanning speed is 10 GHz / s;

[0048] (2) The signal processing board samples at a 200k bandwidth (sampling rate 256k) and performs signal template sampling every 5 seconds (acquisition duration is 1s);

[0049] (3) The number of signals other than the three major operators in the frequency range of 1G - 3.6G is 500;

[0050] (4) The description of the signal processing board is: frequency (8 bytes), bandwidth (4 bytes), amplitude (1 byte). Signal sorting is performed once every 5 seconds using the maximum spectrum. The data volume of one signal template is 13 Byte;

[0051] (5) The number of new signals (interference signals): 100.

[0052] In the electromagnetic environment monitoring scenario, the types of data generated are: FFT spectrum data, signal sorting data, and IQ sample data. Data volume evaluation:

[0053] FFT spectrum data = 10G / 25k (step) * 1Byte (the size occupied by the amplitude value of each channel) ≈ 0.4 MByte / s

[0054] Signal sorting data = 13 * 500 ≈ 6.4 kByte / time

[0055] Signal template sampling data volume = 256 * 1024 * 4Byte (I and Q sampling points each occupy 2 bytes) = 1 MByte / s

[0056] Embodiment 3:

[0057] This embodiment uses the assumed parameters set in Embodiment 2, and the application scenario is interference signal recognition and target positioning, that is, the electromagnetic environment of the current area is tested through electromagnetic environment monitoring, and new signals or interference signals that appear are automatically recognized and direction-finding located. In this application scenario, the system will generate data such as intermediate FFT spectrum data, new signal (interference signal) sorting data, FFT intermediate frequency data, IQ data, signal parameter measurement results, and signal direction-finding results. The types of data generated in the interference signal recognition and target positioning scenario are: FFT spectrum data, new signal (interference signal) sorting data, IQ sample data, FFT intermediate frequency data, signal parameter measurement results, and signal direction-finding results. The data volume evaluation results are:

[0058] FFT spectrum data = 10GHz / 25k (step size) * 1Byte (size occupied by each channel amplitude value) ≈ 0.4MByte / s,

[0059] New signal (interference) sorting data = 13 * 100 ≈ 1.3kByte / time,

[0060] IQ sample data = 256 * 1024 * 4Byte (I and Q sampling points each occupy 2 bytes) = 1MByte / s, FFT intermediate frequency data = 256 * 1024 * 1Byte (amplitude value of one sampling point) 250kByte / s,

[0061] Signal parameter measurement results + signal direction-finding results ≈ 1kByte / s.

[0062] This embodiment analyzes the results of Embodiment 2 and 3. Embodiment 2 will generate 1.0064MByte / s of data, while Embodiment 3 will generate 2.3kByte / s of data. Therefore, the required network bandwidth is approximately 10Mbps. If the IQ data is transmitted by airborne storage and ground wired transmission, the network bandwidth is approximately 51.2kbps; from the perspective of user-friendliness, the network bandwidth required for Embodiment 2 and 3 is approximately 8Mbps. Through the above analysis, for a 20Mbps / s network bandwidth resource, all data can be transmitted in real time; for a 62.5kbps network bandwidth adaptation, necessary data (signal sorting data, interference sorting data, signal parameter measurement results, and signal direction-finding results) are transmitted in real time, while FFT data and IQ sampling data are stored on board and transmitted by ground wired transmission.

[0063] The software and algorithms not described in detail in this article are all general technologies in this field.

Claims

1. A UAV interference monitoring and direction finding device, wherein the UAV-borne interference monitoring and direction finding device is mounted on a UAV, and is characterized in that: The invention comprises a monitoring direction-finding antenna, a monitoring direction-finding host and a ground control terminal. The monitoring direction-finding antenna comprises a monitoring direction-finding antenna array, a switch and an electronic compass, and the monitoring direction-finding antenna array, the switch and the electronic compass are installed in a radome; the monitoring direction-finding host comprises a three-channel receiving channel module, an intermediate frequency signal processing board, a single-board computer and a wireless data transmission device; the ground control terminal is loaded with navigation interference monitoring direction-finding software; the three-channel receiving channel module is connected to the intermediate frequency signal processing board, the intermediate frequency signal processing board is connected to the single-board computer, the single-chip computer is connected to the wireless data transmission device, the monitoring direction-finding antenna is connected to the three-channel receiving channel module of the monitoring direction-finding host, the wireless data transmission device is shared with the wireless data transmission device of the unmanned aerial vehicle, and the monitoring direction-finding host is connected to the ground control terminal through the wireless data transmission device.

2. The UAV interference monitoring and direction finding device according to claim 1 is characterized in that: The monitoring direction finding antenna array adopts a five-element monitoring direction finding antenna array or a nine-element monitoring direction finding antenna array, the aperture of the antenna array is 227mm, the antennas in the antenna array are active dipole antennas, the internal power supply is DC+5V, and the current is 80mA.

3. The UAV interference monitoring and direction finding device according to claim 1 is characterized in that: The switch is a five-choice-three switch.

4. The UAV interference monitoring and direction finding device according to claim 1 is characterized in that: The electronic compass uses an RS232 interface with a baud rate of 9600.

5. The UAV interference monitoring and direction finding device according to claim 1 is characterized in that: The monitoring direction-finding antenna is installed on the UAV through a fixed bracket, and the fixed bracket consists of two parts: a fixed part and a movable part. The fixed part is fixedly installed on the bottom of the belly of the UAV, and a blind plug connector that cooperates with each other is provided at the connection between the fixed part and the movable part. A mounting nut is installed on the side of the movable part, and the movable part is connected to the fixed part through the blind plug connector and the mounting nut.

6. The UAV interference monitoring and direction finding device according to claim 1 is characterized in that: The three-channel receiving channel module includes a local oscillator unit, a channel unit, and a calibration / power supply control unit. The calibration / power supply control unit is connected to the local oscillator unit and the three channel units respectively. The three channel units each include a low-noise amplifier, a filter, and an intermediate frequency filter. A frequency synthesizer is provided between the filter and the intermediate frequency filter, and the three channel units share one frequency synthesizer.

7. The UAV interference monitoring and direction finding device according to claim 1 is characterized in that: The intermediate frequency signal processing board includes an FPGA chip, an analog-to-digital converter, a 102.4M high-precision clock, an onboard FLASH, a synchronous dynamic random access memory, a GPS positioning unit, a broadband power supply and a 100M Ethernet interface. The FPGA chip is respectively connected to the analog-to-digital converter, the 102.4M high-precision clock, the onboard FLASH, the synchronous dynamic random access memory and the GPS positioning unit. The broadband power supply provides power for various components of the intermediate frequency signal processing board. An analog interface is set on the left side of the intermediate frequency signal processing board, and a digital interface is set on the right side.

8. The UAV interference monitoring and direction finding device according to claim 1 is characterized in that: The monitoring and direction-finding host is installed in a host box, the upper cover of the host box is covered on the lower box, and a rubber sealing ring is provided at the connection between the lower box and the upper cover, so that the upper cover and the lower box are sealed and connected; the lower cover is installed at the bottom of the lower box, and a digital board, a single-board computer, a receiver and a power module are installed on the lower cover, and the digital board, the single-board computer, the receiver and the power module are connected according to general electrical principles; the upper cover adopts a detachable cover plate, and the host box is placed in the payload cabin of the drone.

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