GNSS (Global Navigation Satellite System) occultation and sea reflex comprehensive detection system based on unmanned aerial vehicle platform

Abstract

The invention provides a GNSS occultation and sea anti-detection integrated detection system based on an unmanned aerial vehicle platform. The GNSS occultation and sea anti-detection integrated detection system comprises a star-covering sea anti-detection load and ground detection system arranged in an integrated cabin; wherein the ground detection system serves as a medium of the detection load and the unmanned aerial vehicle platform so as to carry out data transmission between the detection load and the unmanned aerial vehicle platform; the detection load sends meteorological detection data to the unmanned aerial vehicle platform through the Camera Link interface, the unmanned aerial vehicle platform is used for providing power supply for the detection load and the ground detection system, the unmanned aerial vehicle platform is further used for providing a positioning antenna signal for the detection load, and the signal is provided by a positioning antenna of the unmanned aerial vehicle platform through a power divider in a branching mode. According to the invention, a high-performance unmanned aerial vehicle is used as a carrying carrier, and a starry sea-covering anti-detection load is carried, so that the problem of serious consequences caused by untimely acquisition of meteorological information under special conditions can be solved, and the life and property safety of the masses can be better guaranteed.

Description

Technical Field

[0001] The present application belongs to the field of navigation detection technology, and in particular to a GNSS occultation and sea anti-satellite integrated detection system based on an unmanned aerial vehicle platform. Background Art

[0002] With the rising sea level caused by global warming and the increasing frequency of extreme natural disasters, the demand for real-time and accurate extreme weather warnings is becoming more and more urgent and important. Occultation detection and sea reflection detection technologies are currently the most promising means of meteorological detection. They are particularly suitable for such meteorological detection needs because of their real-time, high accuracy and unaffected by bad weather.

[0003] Occultation detection and sea reflection detection technology is currently a comprehensive detection method with great potential in the field of meteorology. Its basic principle is to use specific occultation and sea reflection payloads to receive occultation signals emitted by GNSS navigation satellites and navigation star signals after reflection from the surface or ocean. After being processed by a special algorithm through the internal data processing system of the payload, the temperature, humidity, air pressure and surface vegetation, snow coverage, etc. of the path passed by the navigation star signal can be calculated. It has the advantages of good real-time performance, high precision, and not being affected by complex weather.

[0004] However, the carriers of occultation and sea anti-detection payloads are basically artificial satellites, and their application environment is mostly in the space field, which brings the problem of high application cost. The reason is that in the aerospace field, all detection payloads need to undergo strict reliability tests, such as environmental experiments, thermal vacuum experiments, and radiation resistance experiments. In addition, the high cost of rocket launches is also a major factor leading to high costs, which makes it difficult to popularize and apply occultation and sea anti-detection technology. In addition, the satellite-borne occultation and sea anti-detection payloads cannot detect the weather conditions and surface conditions in a specific area in a timely manner and cannot obtain real-time information. Summary of the invention

[0005] In view of this, the present application aims to propose a GNSS occultation and sea reflection integrated detection system based on an unmanned aerial vehicle platform to solve at least one of the above problems.

[0006] To achieve the above purpose, the technical solution of this application is implemented as follows: This application provides a GNSS occultation and sea reflection integrated detection system based on an unmanned aerial vehicle platform, including: The occultation sea anti-detection payload and ground inspection system are installed in the integrated cabin; The ground inspection system serves as a medium between the detection load and the UAV platform to transmit data between the detection load and the UAV platform; the detection load sends the meteorological detection data to the UAV platform through the Camera Link interface, and the UAV platform is used to provide power supply for the detection load and the ground inspection system. The UAV platform is also used to provide the detection load with a positioning antenna signal, which is provided by the positioning antenna of the UAV platform through a power divider. Two sets of communication interfaces are used between the UAV platform and the detection payload to exchange remote control telemetry data and UAV attitude information.

[0007] Furthermore, a preamplifier is also provided in the integrated cabin for power amplification of the signal collected by the front-end antenna; Wherein, the preamplifier includes an occultation preamplifier and a sea reflection preamplifier, and the front-end antenna includes a positioning antenna, a forward occultation antenna, a backward occultation antenna and a sea reflection antenna; The positioning antenna is used to receive the positioning signal provided by the UAV platform, and is given to the occultation preamplifier via a power divider. The forward occultation antenna and the backward occultation antenna are used to receive the occultation transmission signals on both sides of the UAV flight direction, and are given to the occultation preamplifier for signal power amplification. The sea reflection antenna is located at the bottom of the integrated cabin, and is used to receive the sea reflection signal and give it to the sea reflection preamplifier for signal power amplification.

[0008] Furthermore, the forward occultation antenna and the backward occultation antenna are respectively fixed to the frames on both sides of the cabin through corresponding occultation antenna brackets, the integrated cabin is hoisted on two integrated cabin hoisting beams through the integrated cabin bracket, the sea reflection antenna is fixed on the sea reflection antenna bracket, and the sea reflection antenna bracket is fixedly connected to the lower surface of the integrated cabin.

[0009] Furthermore, the detection payload transmits the processed detection data to the ground inspection system through the differential LVDS data transmission format. After receiving the detection data, the ground inspection system converts it into multi-channel parallel LVCMOS data through the internal FPGA processor and sends it to the Camera Link driver. The Camera Link driver converts the multi-channel parallel LVCMOS data into Camera Link data and transmits it to the UAV platform. A Camera Link receiver module is provided between the ground inspection system and the UAV platform to be compatible with loop self-test; The remote control instructions between the ground inspection system and the UAV platform are transmitted via an asynchronous RS422 interface, and the detection payload and the status of each unit of the ground inspection system are sent to the UAV platform in the form of telemetry parameters via the asynchronous RS422 interface for real-time monitoring; The UAV platform sends the real-time flight attitude information when performing the mission to the ground inspection system through a single asynchronous RS422 interface for data solution reference.

[0010] Furthermore, the power supply of the ground inspection system is converted from the 28V voltage of the detection payload receiving drone platform to 12V via an external DCDC conversion module, and then transmitted to the ground inspection system via an inter-board connector of the ground inspection system.

[0011] Furthermore, the ground inspection system and the detection payload are respectively connected to the UAV platform via a Gigabit network port, which is used for transmission of detection storage data between the detection payload and the ground inspection system.

[0012] Furthermore, the ground inspection system adopts an FPGA+ARM architecture, serial communication is performed between the FPGA processor and the ARM controller, and the ARM controller performs two-way communication and transmission with the detection payload through primary and backup CAN communication.

[0013] Furthermore, the ARM controller is also linked to a watchdog circuit, which includes a monitoring chip, wherein the first pin of the monitoring chip is connected to the VCC3V3ARM voltage source through a first resistor, and is connected to the VCC3V3ARM voltage source through a second resistor, a connector and a fourth resistor, the first pin of the monitoring chip is also connected to the eighth pin of the monitoring chip through a second resistor, and the sixth pin of the monitoring chip is connected to the ARM chip.

[0014] Furthermore, in response to a software anomaly or runaway, the sixth pin of the monitoring chip cannot receive a dog feeding signal, triggering the eighth pin to be pulled low, and then triggering the first pin to be pulled low, thereby causing the seventh pin to be pulled low to perform a chip reset operation.

[0015] Furthermore, the monitoring chip adopts a MAX706SESA chip.

[0016] Compared with the prior art, the GNSS occultation and sea reflection integrated detection system based on the UAV platform described in this application has the following beneficial effects: This application relies on a high-performance UAV as a carrier, equipped with an occultation sea anti-detection payload, which can give full play to the advantages of this detection technology. It is suitable for meteorological detection and surface detection in extreme weather or extreme climate conditions. It can well solve the problem of serious consequences caused by untimely acquisition of meteorological information in special circumstances, and better protect the safety of people's lives and property. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The drawings constituting a part of the present application are used to provide a further understanding of the present application. The illustrative embodiments and descriptions of the present application are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings: Figure 1 This is a block diagram of the signal interaction relationship between the integrated cabin and the UAV platform described in the embodiment of the present application; Figure 2 This is a block diagram of the interaction relationship between the internal equipment of the integrated cabin described in the embodiment of the present application; Figure 3 A block diagram of the signal interaction relationship between the integrated detection system and the UAV platform described in the embodiment of the present application; Figure 4 The watchdog circuit diagram described in the embodiment of the present application; Figure 5 This is a schematic diagram of the reset logic of the watchdog circuit described in an embodiment of the present application. DETAILED DESCRIPTION

[0018] In order to make the objectives, technical solutions and advantages of the present application more clearly understood, the present application is further described in detail below in combination with specific embodiments and with reference to the accompanying drawings.

[0019] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in the embodiments of the present application should be the usual meanings understood by people with ordinary skills in the field to which the present application belongs. The "first", "second" and similar words used in the embodiments of the present application do not represent any order, quantity or importance, but are only used to distinguish different components. "Including" or "comprising" and similar words mean that the elements or objects appearing in front of the word cover the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0020] The occultation detection and sea reflection detection technology uses specific occultation detection payloads and sea reflection detection payloads to actively receive navigation star occultation signals transmitted by the GNSS (Global Navigation Satellite System) and reflected signals reflected by the land surface or sea level. During the transmission process, these signals will be affected by the environment of the transmission path and produce corresponding interference, causing key information such as the phase, amplitude and frequency of the navigation star signal to change. After the detection payload receives this change information, it processes and solves it through the special algorithm of the internal data processing system, and can invert the meteorological information near the path passed by the navigation star signal in real time, including parameters such as atmospheric temperature, humidity and air pressure in a specific area, as well as key meteorological parameters such as the electron density of the ionosphere.

[0021] As described in the above background technology, the current occultation sea anti-detection technology is mostly carried by artificial satellites, and its application field is satellite-borne detection, which does not have advantages in manufacturing cost and launch cost as well as local meteorological and surface detection in specific areas. This application proposes to rely on the high maneuverability and environmental adaptability of high-performance UAV platforms, and carry occultation sea anti-detection payloads, so as to better play the meteorological detection technology advantages of occultation sea anti-detection payloads, expand the application fields of local meteorological detection and surface detection, play a greater role in meteorological detection in extremely severe weather, better achieve disaster prevention and mitigation, and make greater contributions to the development of the meteorological field.

[0022] See also Figure 1 As shown, this embodiment provides a GNSS occultation and sea anti-intelligence integrated detection system based on an unmanned aerial vehicle platform, including: The occultation sea anti-detection payload and ground inspection system are installed in the integrated cabin; The ground inspection system serves as a medium between the detection payload and the UAV platform to transmit data between the detection payload and the UAV platform. The detection payload sends meteorological detection data to the UAV platform through the Camera Link interface. The UAV platform is used to provide power supply for the detection payload and the ground inspection system. The UAV platform is also used to provide the detection payload with a positioning antenna signal, which is provided by the positioning antenna of the UAV platform through a power divider. Two sets of communication interfaces are used between the UAV platform and the detection payload to exchange remote control telemetry data and UAV attitude information.

[0023] Specifically, in this embodiment, a design scheme for an integrated occultation and sea countermeasures detection system based on a high-performance UAV platform is proposed. The overall scheme is as follows: the data flow for communication and interaction between the detection payload and the UAV platform is planned in detail, and a ground inspection system for interaction between the UAV platform and the detection payload is designed separately to meet the communication requirements between the occultation and sea countermeasures payload and the UAV; then, the ground inspection system and the integrated detection payload are coupled into a whole through electrical and structural design and placed in a specific integrated cabin; the integrated cabin communicates with the UAV platform as a whole, Figure 1 This is the overall block diagram of the interaction between the integrated cabin and the UAV platform.

[0024] The interior of the integrated cabin mainly includes the occultation sea anti-detection payload and the ground inspection system. The detection payload sends the meteorological detection data to the UAV platform through the CameraLink interface. The UAV platform needs to provide the detection payload and the ground inspection system with the power supply required for normal operation. The voltage rating is 28V and the overall power is not less than 50W. In addition, the UAV platform needs to provide the detection payload with the positioning antenna signal. The signal is provided by the positioning antenna of the UAV platform through a power divider to meet the positioning signal requirements of the detection payload. In addition, two sets of asynchronous RS422 interfaces are used between the UAV platform and the detection payload for remote control telemetry data and interaction of UAV attitude information.

[0025] The detection system described in the present application relies on a high-performance UAV as a carrier, which can give full play to the advantages of the detection technology. It is suitable for meteorological detection and surface detection in extreme weather or extreme climate conditions, such as typhoons, sandstorms, and even real-time weather and surface conditions at the center of earthquakes. It can well solve the problem of serious consequences caused by untimely acquisition of meteorological information in special circumstances, better protect the lives and property of the people, better prevent and reduce disasters, and is applicable to meteorological support for some major events and mobile detection support tasks.

[0026] Figure 2The diagram is a block diagram of the internal configuration of the integrated cabin and the interaction relationship with the external antenna. The internal structure of the integrated cabin mainly includes the GNSS occultation and sea anti-intelligence integrated detection and receiving system, the ground inspection system, the power conversion module, and the preamplifier module. Among them, the GNSS occultation and sea anti-intelligence integrated detection and receiving system is the functional core, responsible for processing and solving the detection data received by the antenna to realize the function of outputting meteorological detection data. The ground inspection system is the medium for the interaction between the detection payload and the UAV platform, realizing the data transmission between the payload and the platform; and it is plugged into the detection and receiving system through a dedicated board connector to realize the structural and electrical coupling between the two, and become one with the detection and receiving system, so that the signal connection is simpler and the transmission is more reliable, and no extra external cables and various types of connector solutions are required, which reduces the cost and the overall weight and volume; the power conversion module is responsible for converting the 28V power supply voltage provided by the UAV platform into the 12V voltage required for the normal operation of the detection and receiving system and the ground inspection system; the preamplifier module is responsible for amplifying the power of the signal collected by the front-end antenna to meet the signal power requirements of the data processing system. Specifically, it can be divided into an occultation preamplifier and a sea reflection preamplifier. The occultation preamplifier is used to amplify the positioning signal, forward occultation signal and backward occultation signal, and the sea reflection preamplifier is used to amplify the sea reflection signal.

[0027] The external antenna requires four types of detection antennas, namely positioning antenna, forward occultation antenna, rearward occultation antenna and sea reflection antenna. The positioning antenna is used to receive positioning signals. The positioning signals are provided by the UAV platform and given to the preamplifier in the integrated cabin through a power divider; the forward occultation antenna and the rearward occultation antenna are used to receive occultation transmission signals on both sides of the UAV's flight direction. The sea reflection antenna is located at the bottom of the integrated cabin and is used to receive reflected navigation star signals.

[0028] The payload cabin of the UAV platform needs to be equipped with an installation truss, and the various components of the detection system are installed in the payload cabin. According to the mechanical interface requirements, the two occultation antennas need to be fixed to the frames on both sides of the cabin through the left occultation antenna bracket and the right occultation antenna bracket respectively, the integrated cabin body is hoisted on the two integrated cabin hoisting beams through the integrated cabin body bracket, the sea reflection antenna is fixed on the sea reflection antenna bracket, and the sea reflection antenna bracket is connected to the lower surface of the integrated cabin by bolts.

[0029] In particular, a radome is required on the outside of the detection antenna, which is anti-collision, waterproof, dustproof, and anti-corrosion, and can ensure that the antenna can stably and reliably capture detection information during the mission. In particular, the radome cannot be made of metal, cannot affect the normal reception of signals, and must have sufficient hardness, good sealing, and can be tightly coupled with the receiving surface of the antenna.

[0030] Figure 3The following is a detailed schematic diagram of the signal cross-linking relationship between the ground inspection system, the UAV platform, and the occultation and sea counter-intelligence integrated detection payload. The main processor architecture of the ground inspection system is the FPGA+ARM architecture. The electrical connection between it and the detection payload mainly includes power supply, data transmission, and CAN communication. The power supply of the ground inspection system is received by the detection payload from the UAV platform. After the voltage is converted to 12V via an external DCDC, it is transmitted to the ground inspection system through the inter-board connector of the ground inspection system. For data transmission, the detection payload transmits the processed data to the ground inspection system in the differential LVDS data transmission format; CAN communication is to meet the needs of control signals and related command communications between the detection payload and the ground inspection system. It is a two-way transmission, using the CAN_A and CAN_B master-slave design, which has higher reliability.

[0031] After the ground inspection system receives the detection data sent by the payload, it is first converted into multi-channel parallel LVCMOS data through the internal FPGA processor and sent to a dedicated Camera Link driver chip. The driver chip converts the multi-channel parallel LVCMOS data into dedicated Camera Link data and transmits it to the UAV platform. At the same time, a Camera Link receiver module is added to the Camera Link driver, which is designed to be compatible with loop self-test, realizes the self-test function of the detection data, and ensures the reliability and stability of the data transmission path performance. The Camera Link interface is a commonly used standard data interface for high-speed data transmission on UAV platforms. It supports high-speed data differential serial transmission, has strong anti-common mode interference capability, and a data transmission rate of up to 85Mbps, which meets the needs of detection data transmission.

[0032] The remote control commands between the ground inspection system and the UAV platform are transmitted through the asynchronous RS422 interface. The detection payload and the status of each unit of the ground inspection system are sent to the UAV platform in the form of telemetry parameters through the asynchronous RS422 interface for real-time monitoring. In addition, the UAV sends the real-time flight attitude information during the mission to the ground inspection system through a separate asynchronous RS422 interface for data solution reference.

[0033] In particular, the system adds a Gigabit Ethernet port to the ground inspection system and the detection payload respectively, which is used for the detection storage data transmission between the detection receiving system and the ground inspection system. The Camera Link data transmits the detection data to the UAV platform in real time, while the detection storage data synchronizes and stores the data collected by the detection payload in the internal large-capacity storage unit, and then sends it to the UAV platform via the Gigabit Ethernet port. The UAV platform collects and records the data. After the UAV platform completes the mission, further data comparison, analysis and processing can be performed.

[0034] The basic peripheral units required for configuration are allocated between the FPGA processor and the ARM controller inside the ground inspection system to ensure that the minimum system can work normally. The necessary SPI Flash and crystal oscillator units need to be configured outside the FPGA processor, and the necessary SPI flash, crystal oscillator and watchdog need to be configured outside the ARM controller to reset the watchdog when an abnormality occurs. The necessary FMC interface, serial port, and SPI interface are reserved between the FPGA processor and the ARM controller. In addition, the ARM controller needs to give the FPGA processor a reset signal to ensure that the FPGA processor can be controlled by the ARM controller to perform a reset operation, thereby improving the reliability of the entire system. The FPGA processor and the ARM controller each add a self-test serial port to maintain two-way communication, which can be used as a test interface for the processor's own performance.

[0035] In particular, the power-on reset logic of the local detection system is implemented in this way. When the UAV platform turns on the power supply to the occultation and sea anti-intelligence integrated detection payload through the power platform, the detection payload simultaneously turns on the power supply to the ground detection system. After that, when the watchdog detects that the voltage rises and meets the working voltage, the watchdog will perform a power-on reset operation. The reset time is 200ms, which is enough time for ARM to complete the startup program reload and power on other modules of the ground detection system. The specific watchdog circuit of this application is as follows: Figure 4 As shown, it is described in detail below.

[0036] The core device U35 of the watchdog circuit is ADI's MAX706SESA. This chip supports power-on reset and soft reset, which can well meet the power supply monitoring and software reliability monitoring requirements of the ground detection system. Pin 7 RESET_N is the chip reset pin. When VCC does not meet the threshold condition, or the MR pin (Manul Reference, manual reset pin) is pulled low, the reset enable will be triggered.

[0037] When the chip power supply voltage VCC rises above 1V, the 7-pin RESET_N will be pulled low to start the power-on reset. When VCC continues to rise and exceeds the reset threshold voltage of 3V, the internal timer of the chip will start timing and release RESET_N after 200ms. The duration of 200ms can well meet the requirements of power supply stability. It ensures that the reset function is released after the power supply is stable enough to ensure system voltage stability and improve system reliability.

[0038] Pin 6 WDI is the input pin for feeding the dog signal. This pin is directly connected to the ARM chip. The ARM chip needs to ensure that the rising or falling edge pulse of this pin is given within at least 1.6S, otherwise it will trigger the 8-pin WDO to be enabled, that is, when the WDI pin does not receive the pulse edge from the ARM chip for more than 1.6S, the WDO pin will be immediately pulled low and continue to maintain a low level state until the WDI pin receives a pulse edge trigger from the ARM chip, and the WDO pin will restore the high level. However, the WDO pin is different from the RESET_N pin. After the RESET_N pin is triggered and pulled low, even if the trigger condition is immediately released, it will remain at a low level for about 200ms, which reserves sufficient time for the execution of related program reset, clock initialization, and related peripheral initialization (GPIO, Uart, ADC or DAC). Therefore, the RESET_N pin is selected as the reset signal output pin.

[0039] Therefore, the present application connects the WDO pin to the MR pin through a resistor, so that when the software runs abnormally, it will trigger the WDO pin to be pulled low, and then trigger the MR pin to be pulled low, thereby causing the RESET_N pin to be pulled low, and resetting the software program, thus satisfying the processor chip's need for sufficient reset time.

[0040] In particular, for the watchdog circuit, the present application also designs a dog-off function. Since the watchdog is not required to function during the debugging phase, a suitable and simple solution is required to flexibly turn the watchdog on and off. The present application implements the watchdog on and off function in this way, as described below: like Figure 4 and Figure 5 As shown, J12 is a connector for connecting the watchdog signal DOG_OFF3 and the VCC3V3ARM voltage. In actual use, it is two pins with a spacing of 2.54mm. When the watchdog function needs to be turned off, the two pins are short-circuited through the jumper cap, that is, the DOG_OFF3 signal is connected to the power supply. Then, according to the resistor voltage division of the schematic diagram, the resistance value of R583 is 100Ω, and the resistance value of R584 is 1KΩ. At this time, the MR pin will be clamped at 3V, that is, the MR pin will be forced to maintain a high level. At this time, even if the processor does not feed the dog and the WDO pin is pulled low, it will not cause the MR pin to be pulled low, thus realizing the watchdog function.

[0041] When the software debugging is completed, just unplug the jumper cap to release the forced clamp of the MR pin. R587 is a 10KΩ resistor. When the software runs normally, the resistor will act as a pull-up resistor and pull the MR pin to a high level. When an abnormality occurs, according to the principle of resistor voltage division, WDO is pulled low, and a complete loop is formed between the power supply, R587, R584 and WDO pin. At this time, the voltage at the MR pin is 0.3V, that is, the MR pin is pulled low, which will trigger the RESET_N pin action and reset the processor.

[0042] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. These modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be included in the scope of the claims and specification of the present invention.

[0043] The embodiments of the present application are intended to cover all such substitutions, modifications and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the embodiments of the present application should be included in the scope of protection of the present application.

Claims

1. A GNSS occultation and sea reflection integrated detection system based on an unmanned aerial vehicle platform, characterized in that: include: The occultation sea anti-detection payload and ground inspection system are installed in the integrated cabin; The ground inspection system serves as a medium between the detection load and the UAV platform to transmit data between the detection load and the UAV platform; the detection load sends the meteorological detection data to the UAV platform through the Camera Link interface, and the UAV platform is used to provide power supply for the detection load and the ground inspection system. The UAV platform is also used to provide the detection load with a positioning antenna signal, which is provided by the positioning antenna of the UAV platform through a power divider. Two sets of communication interfaces are used between the UAV platform and the detection payload to exchange remote control telemetry data and UAV attitude information.

2. The system according to claim 1, characterized in that: The integrated cabin is also provided with a preamplifier for amplifying the power of the signal collected by the front-end antenna; Wherein, the preamplifier includes an occultation preamplifier and a sea reflection preamplifier, and the front-end antenna includes a positioning antenna, a forward occultation antenna, a backward occultation antenna and a sea reflection antenna; The positioning antenna is used to receive the positioning signal provided by the UAV platform, and is given to the occultation preamplifier via a power divider. The forward occultation antenna and the backward occultation antenna are used to receive the occultation transmission signals on both sides of the UAV flight direction, and are given to the occultation preamplifier for signal power amplification. The sea reflection antenna is located at the bottom of the integrated cabin, and is used to receive the sea reflection signal and give it to the sea reflection preamplifier for signal power amplification.

3. The system according to claim 2, characterized in that: The forward occultation antenna and the backward occultation antenna are respectively fixed to the frames on both sides of the cabin through corresponding occultation antenna brackets, the integrated cabin is hoisted on two integrated cabin hoisting beams through the integrated cabin bracket, the sea reflection antenna is fixed on the sea reflection antenna bracket, and the sea reflection antenna bracket is fixedly connected to the lower surface of the integrated cabin.

4. The system according to claim 1, characterized in that: The detection payload transmits the processed detection data to the ground inspection system through the differential LVDS data transmission format. After receiving the detection data, the ground inspection system converts it into multi-channel parallel LVCMOS data through the internal FPGA processor and sends it to the Camera Link driver. The Camera Link driver converts the multi-channel parallel LVCMOS data into Camera Link data and transmits it to the UAV platform. A Camera Link receiver module is provided between the ground inspection system and the UAV platform to be compatible with loop self-test; The remote control instructions between the ground inspection system and the UAV platform are transmitted via an asynchronous RS422 interface, and the detection payload and the status of each unit of the ground inspection system are sent to the UAV platform in the form of telemetry parameters via the asynchronous RS422 interface for real-time monitoring; The UAV platform sends the real-time flight attitude information when performing the mission to the ground inspection system through a single asynchronous RS422 interface for data solution reference.

5. The system according to claim 4, characterized in that: The power supply of the ground inspection system is converted from the 28V voltage of the drone platform received by the detection payload to 12V via an external DCDC conversion module, and then transmitted to the ground inspection system through the inter-board connector of the ground inspection system.

6. The system according to claim 4, characterized in that: The ground inspection system and the detection payload are respectively connected to the UAV platform via a Gigabit network port, which is used for the detection storage data transmission between the detection payload and the ground inspection system.

7. The system according to claim 4, characterized in that: The ground inspection system adopts FPGA+ARM architecture, serial communication is performed between the FPGA processor and the ARM controller, and the ARM controller performs two-way communication transmission with the detection payload through primary and backup CAN communication.

8. The system according to claim 7, characterized in that: The ARM controller is also linked to a watchdog circuit, which includes a monitoring chip. The first pin of the monitoring chip is connected to the VCC3V3ARM voltage source through a first resistor, and is connected to the VCC3V3ARM voltage source through a second resistor, a connector and a fourth resistor. The first pin of the monitoring chip is also connected to the eighth pin of the monitoring chip through a second resistor, and the sixth pin of the monitoring chip is connected to the ARM chip.

9. The system according to claim 8, characterized in that: In response to software anomalies or runaway, the sixth pin of the monitoring chip cannot receive the dog feeding signal, triggering the eighth pin to be pulled low, and then triggering the first pin to be pulled low, thereby causing the seventh pin to be pulled low to perform a chip reset operation.

10. The system according to claim 8, characterized in that: The monitoring chip adopts MAX706SESA chip.

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