Portable UAV Ground Telemetry Receiving System

Abstract

A portable UAV ground telemetry receiving system disclosed by the present invention is convenient to carry, fast in transferring sites, and flexible in station deployment, and is realized through the following technical solutions: The ground station monitoring device starts the monitoring thread of the system monitoring software to perform "one-key" loading and setting of the working parameters of all devices. The antenna-tower-feed device adjusts the pointing of the directional antenna, and adopts a single-channel monopulse system to obtain the telemetry data of the target. After completing the capture and tracking of the target, the received RF signal is sent to the telemetry receiving device. The filter switching unit selects and calls the corresponding filtering algorithm to amplify and filter the RF signal. The processed RF signal is sent to the telemetry receiving baseband device for signal frequency conversion and demodulation. The demodulated telemetry data is sent to the decryption machine for processing through the network port. At the same time, the relevant information of the UAV is received in real time, the current position of the UAV is estimated, and the downlink data sent back to the ground is used to "graphically" display the working states and parameters of all devices.

Description

Technical Field

[0001] The present invention relates to the field of measurement and control communication, and particularly to a portable ground telemetry receiving system for a UAV aircraft applicable to application fields such as UAV aerial photography, agriculture, plant protection, self-timer, express delivery, disaster relief, wildlife observation, surveying and mapping, news reporting, power inspection, disaster relief, film and television shooting, reconnaissance, UAV combat, etc. Background Art

[0002] With the rapid development of UAVs, they have been widely used in military and civilian fields. The types and amounts of data transmitted in space have increased, imposing heavier tasks and higher requirements on telemetry ground stations, and new demands are constantly emerging. As an important part of the UAV system, the main task of the UAV ground telemetry receiving system is to receive, process, and display telemetry data such as the flight status of the UAV and the working status of the mission payload in real time. The performance of the UAV telemetry receiving system largely determines the overall performance of the UAV system and is the "nerve center" link between the UAV and the ground station.

[0003] Since traditional UAV ground telemetry receiving systems are generally deployed in a fixed manner, UAVs and other aircraft must go to a designated test flight field. Beyond this telemetry range, measurement and control operations cannot be carried out, which severely restricts the use range of UAVs. The cabinets configured in traditional fixed-deployment ground measurement and control systems are generally designed to be 1600 mm high, 600 mm wide, and 480 mm deep, with a relatively heavy weight that cannot be moved by one person and cannot be moved after installation. Moreover, the equipment of traditional UAV ground telemetry receiving systems is complex, with poor versatility, flexibility, and stability. The antennas configured are parabolic antennas, which not only have a large aperture, are complex to install, but also have a large weight, with poor mobility and flexibility. At the same time, in order to meet the requirements of multiple systems and multiple targets, traditional UAV ground telemetry receiving systems configure multiple links for the receiving channels, with a large amount of equipment and a high degree of integration, and complex software operations, requiring a large amount of time for pre-task preparation work. Therefore, there is an urgent need to develop a UAV ground telemetry receiving system with a small volume, good portability, high precision, capable of rapid deployment at any site, simple operation, and having convenience and mobility. Summary of the Invention

[0004] The purpose of the present invention is to address the deficiencies existing in the prior art and provide a portable UAV ground telemetry receiving system with advantages such as being easy to carry, fast in transferring sites, flexible in station layout, etc. At the same time, the system configuration is flexible, the operation is convenient, and the cost is relatively low. Using this system can solve the problems of poor mobility and complex operation of traditional measurement and control ground stations.

[0005] The technical solution adopted by the present invention to solve the above technical problems is as follows: A portable UAV ground telemetry receiving system, comprising: a telemetry cabinet 2 with universal wheels at the bottom of the cabinet, a tracking antenna device 1 supporting the telemetry cabinet 2, a ground station monitoring device 3, a telemetry receiving device 4 and a power supply 5 stored in the cabinet body of the telemetry cabinet 2. It is characterized in that: the tracking antenna device 1 adjusts the direction of the directional antenna according to the orbit parameters issued by the ground station monitoring device 3 and continuously guides the directional antenna to receive the telemetry signal of the UAV, and adopts a single-channel monopulse system to obtain the telemetry data of the target; after completing the capture and tracking of the target, the received RF signal is sent to the ground station monitoring device 3 through the telemetry receiving link. The ground station monitoring device 3 starts the monitoring thread of the system monitoring software to perform "one-key" loading and setting of the working parameters of all devices, and can also issue the UAV flight orbit plan issued by the UAV measurement and control center through the network interface. The telemetry receiving device 4 selects and calls the corresponding filtering algorithm according to the working parameters issued by the ground station monitoring device 3 to amplify and filter the RF signal. The processed RF signal is sent to the frequency conversion module integrated in the telemetry receiving baseband device for signal frequency conversion and demodulation. The demodulated telemetry data is sent to the decryption machine for processing through the network port, and at the same time, relevant UAV information is received in real time, the current position of the UAV is estimated, and the downlink data sent back to the ground is used to "graphically" display the working status and parameters of all devices.

[0006] The beneficial effects of the present invention compared with the prior art are as follows:

[0007] The present invention comprehensively considers issues such as the complexity, stability, reliability of the system, and the sharing of transmitting and receiving antennas. The telemetry cabinet 2 with casters at the bottom of the cabinet is used to store the ground station monitoring equipment 3, telemetry receiving equipment 4, and power supply 5. It is light in weight, equipped with casters at the bottom, with a self-locking function, and can be pushed away by one person for movement. It can be deployed and retracted quickly, is convenient to carry, and is flexible for station setup. The telemetry cabinet 2 is designed with a height of 610 mm, a width of 590 mm, and a depth of 860 mm. Compared with the cabinet design of the traditional fixed-deployment ground measurement and control system with a height of 1600 mm, a width of 600 mm, and a depth of 480 mm, it is small in volume, light in weight, good in portability, fast in movement, and fast in site transfer. The outer shell of the cabinet body adopts a rotational molding box structure, which is sealed, waterproof, dustproof, and shock-absorbing, and has the performance of impact resistance, low-temperature resistance, and anti-deformation ability; the inside of the cabinet is equipped with a 19-inch rack with a height of 10U. The rack itself adopts an aluminum alloy structure, and the outer shell and the rack part are connected with shock absorption, which can effectively reduce the vibration during transportation and is suitable for any transportation environment. In particular, the antenna servo equipment supporting the telemetry cabinet 2 abandons the parabolic antenna with a large aperture, complex installation, and large weight. It not only overcomes the defects of poor mobility and flexibility of the parabolic antenna, but also greatly improves the tracking accuracy, reduces the hardware configuration of the traditional telemetry receiving chain, and reduces the dynamic lag error. By adjusting the direction of the directional antenna through the antenna servo equipment 1 and continuously guiding the directional antenna to receive the telemetry signal of the UAV, the aperture of the directional antenna is much smaller than that of the parabolic antenna of the traditional ground measurement and control station, which is convenient to carry and has strong mobility, solving the problems of poor mobility and complex operation of the traditional measurement and control ground station.

[0008] The present invention uses a single-channel monopulse system to obtain the measurement data of the target, which can significantly simplify the complexity of the system, significantly improve the working reliability, significantly reduce the dynamic lag, save the channel, simplify the technical intersection link, and reduce the equipment cost. The telemetry receiving baseband equipment adopts a modular and ruggedized portable platform. Each functional module is modularly designed. Its outstanding environmental index characteristics, rugged and reliable structural design, and more secure connection and plug-in performance are more suitable for use in harsh environments. Compared with the previous telemetry receiving equipment, the traditional telemetry receiving baseband adopts an industrial computer form, with a larger volume and weight. While this telemetry baseband adopts a 1U plug-in box structure, both the weight and volume are well controlled; at the same time, the frequency conversion module is integrated into the telemetry receiving baseband, reducing the down-conversion equipment, reducing the cost while reducing the number of equipment, making the entire UAV telemetry receiving system more portable, fast in site transfer, and flexible in station setup, etc., with mobility advantages.

[0009] The present invention comprehensively considers factors such as the convenience, stability, reliability, and mobility of the system. The used antenna servo feed device 1 adjusts the pointing of the directional antenna according to the orbit parameters issued by the ground station monitoring device 3 and continuously guides the directional antenna to receive the telemetry signal of the unmanned aerial vehicle. By adopting a single-channel monopulse system to obtain the measurement data of the target, the complexity of the system can be significantly simplified, the reliability of operation can be significantly improved, the dynamic lag can be significantly reduced, the channel is saved, the technical crossover link is simplified, and the equipment cost is reduced. The azimuth branch of the antenna servo feed device 1 has a secant compensation function, which can adapt to the tracking requirements at different elevation angles. After completing the tracking of the target, the received RF signal is sent to the telemetry receiving device 4, and the received RF signal is amplified, frequency-converted, and filtered, reducing the hardware configuration of the traditional telemetry receiving channel. The acceleration constant can be greatly improved, the dynamic lag error is reduced, and the tracking accuracy can be satisfied. After the directional antenna receives the target signal, when the AGC voltage, lock signal indication, error voltage, etc. of the received signal meet the given conditions, the antenna enters the self-tracking state to achieve stable and accurate tracking of the target. It can search, digitally guide, etc. in the predetermined target airspace. The search can be carried out on a single axis of pitch or azimuth, or on both axes simultaneously. Compared with the antenna of the traditional ground measurement and control station, it is much smaller in aperture, easy to carry, and has strong mobility.

[0010] The filter switching unit adopted by the present invention selects and calls the corresponding filtering algorithm to filter the RF signal according to the working parameters issued by the ground station monitoring device 3, effectively solving the interference of out-of-band signals and the influence of out-of-band spurs, and reducing the demodulation error rate of the telemetry receiving baseband.

[0011] The adopted ground station monitoring device 3 of the present invention has a "one-key" loading function for the working parameters of all devices of the portable unmanned aerial vehicle telemetry receiving system, and can also issue the unmanned aerial vehicle flight orbit plan of the unmanned aerial vehicle measurement and control center through the network interface. At the same time, it displays the working status and parameters of all devices in a "graphical" manner. Compared with the software interface of the traditional ground test system, it is simple and concise, and the operation is simple, greatly saving the preparation time for parameter configuration before the task.

[0012] The adopted power supply 5 of the present invention can continuously provide power demand for the portable measurement and control device in the case of no external power supply or power failure. At the same time, in a harsh power grid environment, it can provide reliable, stable, and pure electric energy for the equipment.

[0013] The main technical indicators achieved by the portable UAV ground telemetry receiving system are as follows: receiving signal frequency range: 2200 MHz to 2300 MHz; antenna gain: receiving: ≥22 dBi @ 2250 MHz; having servo control capabilities in two degrees of freedom of azimuth and pitch, and the tracking modes include digital guidance, automatic, and manual; it is required that each axis can be linked or independently controlled separately, range: azimuth 0 to 360° infinite, pitch 0 to 85°; speed: azimuth: 0° / s to 35° / s, pitch: 0° / s to 30° / s; acceleration: azimuth: 0° / s 2 ~20° / s 2 , pitch: 0° / s 2 ~20° / s 2 ; having the ability to automatically find north and fix north; the whole system has rain and waterproof protection and can work in the field; frequency capture range: ±15 kHz; frequency Doppler change rate: 3 kHz / s; working system: PCM-FM, PCM-BPSK can be set; code rate: adjustable from 10 kbps to 10 Mbps, in steps of 0.1 kbps; receiving sensitivity: better than -96.5 dBm (1.6384 Mbps) dynamic range: 60 dB; FM data processing delay: 30 ms. Description of the Drawings

[0014] The present invention will be further described below in conjunction with the drawings and embodiments.

[0015] Figure 1 is a schematic diagram of the composition of the portable UAV ground telemetry receiving system of the present invention;

[0016] Figure 2 is Figure 1 the working flowchart of the telemetry receiving and processing baseband in Detailed Embodiments

[0017] Refer to Figure 1. In the preferred embodiment described below, a portable UAV ground telemetry receiving system includes: a telemetry cabinet 2 equipped with universal wheels at the bottom of the cabinet, an antenna feed device 1 matched with the telemetry cabinet 2, a ground station monitoring device 3, a telemetry receiving device 4 and a power supply 5 stored in the telemetry cabinet 2, wherein; the antenna feed device 1 adjusts the direction of the directional antenna and continuously guides the directional antenna according to the orbit parameters issued by the ground station monitoring device 3, adopts a single-channel single-pulse system to obtain the telemetry data of the target, and after completing the capture and tracking of the target, sends the received RF signal to the ground station monitoring device 3 through the telemetry receiving link; the ground station monitoring device 3 starts the monitoring software The monitoring thread of all equipment can be loaded and set with one click, and the flight trajectory plan of the UAV issued by the UAV measurement and control center can also be issued through the network interface; the telemetry receiving device 4 selects to call the corresponding filtering algorithm to amplify and filter the RF signal according to the working parameters issued by the ground station monitoring device 3, and the processed RF signal is sent to the frequency conversion module integrated in the telemetry receiving baseband device for signal frequency conversion and demodulation, and the demodulated telemetry data is sent to the decryptor through the network port for processing, and the UAV related information is received in real time, the current position of the UAV and the downlink data sent back to the ground are estimated, and the working status and parameters of all equipment are displayed in a "graphic" way.

[0018] The telemetry cabinet 2 centrally installs the ground station monitoring equipment 3, the telemetry receiving equipment 4 and the power supply 5 in the cabinet. The outer shell adopts the structure of a roto-molded box, and the interior is equipped with a 19-inch rack with a height of 10U. The rack itself adopts an aluminum alloy structure. The roto-molded box and the chassis are connected by shock-absorbing, which can reduce vibration during transportation. The bottom of the box is equipped with four universal wheels for convenient equipment transportation. The airdrop cabinet box is sealed, waterproof, dustproof, and shock-absorbing. It has the performance of impact resistance, low temperature resistance and deformation resistance. It is suitable for any transportation environment and can be recycled for a long time. It is light in weight, can be quickly folded and unfolded, and is easy to carry. The power supply 5 mainly provides power demand for all equipment of the portable unmanned aerial vehicle ground telemetry receiving system. The antenna servo feed device 1 includes: a directional antenna fixedly connected to the antenna turntable and the bracket through an antenna bracket and a servo system connected to a network switch. Among them, the servo system controls the servo control capability of the two degrees of freedom of the antenna turntable in azimuth and pitch according to the parameters issued by the ground station monitoring equipment 3, realizes accurate pointing to the target, and reports the portable reinforced notebook system monitoring software at the same time to control the working status and fault information of the antenna control unit. The servo system tracking modes include digital guidance, automatic, and manual; each axis is required to be linked or independently controlled, with a range of 0 to 360° in azimuth and 0 to 85° in pitch; speed: azimuth: 0° / s to 35° / s, pitch: 0° / s to 30° / s; acceleration: azimuth: 0° / s 2 ~20° / s 2 , pitch: 0° / s 2~20° / s 2 。

[0019] The antenna feed part of the antenna servo equipment 1 receives the telemetry signal for achieving the goal. The servo part adjusts the steering angle of the antenna unit in real time through a digital position regulator. The digital position regulator generates a digital control quantity according to the given control law and sends it to the digital stabilization loop to achieve the tracking and pointing of the goal. By receiving the target angle tracking loop word quantity through the receiving mechanism, the actuator on the antenna pedestal is controlled to drive the antenna to move in the direction of reducing the error until the antenna beam is aligned with the target. After the antenna receives the target signal, when the AGC voltage, lock signal indication, and error voltage of the received signal meet the given conditions, the antenna enters the self-tracking state to achieve stable and accurate tracking of the target.

[0020] In this embodiment, the directional antenna includes a 1×2 feeding network, a 4×4 feeding network, and an antenna unit, mainly for receiving the S-band radio frequency signals sent by aircraft such as unmanned aerial vehicles. To meet the mobility and convenience requirements of the ground measurement and control system, the antenna unit is arranged on a plane of 900mm*450mm. The technical indicators of the directional antenna are as follows: the operating frequency is 2200MHz - 2300MHz, the antenna gain ≥ 20dB, the receiving 3dB beam width AZ: ≤ 12.5°, EL: ≥ 36°, the receiving azimuth first side lobe: ≤ -12dB, and the antenna standing wave ratio: ≤ 1.65.

[0021] In this embodiment, the ground station monitoring device 3 mainly includes a portable rugged notebook or a ruggedized three-proof tablet computer that communicates bidirectionally with the network switch. The network switch performs network topology, physical addressing, network monitoring, error checking, frame sequence management, troubleshooting, and configuration on the virtual local area network (VLAN) through a high-speed connection port. The portable rugged notebook deploys system monitoring software and is interconnected with the antenna servo equipment 1 and the uninterruptible power supply 5 through the network switch and the telemetry receiving device 4. It radiates emission and conducted emission information outward through space and relevant channels, formulates failure criteria according to the anti-radiation index and the performance requirements required by the electronic system, and is ruggedized according to a reasonable safety factor to achieve the monitoring and control of each device.

[0022] The system monitoring software includes a user management module, a task management module, a device monitoring module, a macro management module, a data management module, a configuration management module, and a main interface parameter display module. The user management module accepts user login requests. In the logged-in state, all functions of the software are allowed to be used; in the non-logged-in state, the use of task management functions and control functions is restricted. The task management module automatically obtains the task status, running status, aircraft spatial position, and telemetry information reported during the execution of the portable station task, associates them with relevant work plans, realizes the monitoring of the execution status of work plans, displays and records the changes in the execution status of work plans and task plans, judges the abnormal execution of work plans, and completes functions such as abnormal alarm notification, addition, deletion, modification, and interruption. Each task data has playback and statistical functions. The device monitoring module provides comprehensive network monitoring functions, records and displays device operation parameters or status changes, gives alarm prompts for abnormalities, provides human-computer interaction functions such as displaying the operation block diagram of the portable station, communication link display, and various device units, and ensures the efficient operation of the business system; the macro management module has the ability to control the working parameters of each link device with a "one-key" and functions of addition, deletion, query, modification; the data management module of the governance platform integrates data integration, component management, data exchange, task scheduling, real-time computing and storage, metadata management, data standard management, data quality management, master data management, data asset management, data security management, and data life cycle management. It can query destination logs, status data, and command data through certain indexing strategies and has data maintenance strategies. The data management module obtains the configuration data of users, generates configuration files, combines with the existing system architecture, generates application modules according to the configuration files or database definitions, and then based on the externally provided data structure definitions, makes corresponding data models to expand and meet the needs of various applications; the main interface parameter display module "graphically" shows the working status and parameters of each link device. Compared with the software interface of traditional ground measurement and control systems, it is simple and concise, and the operation is simple, greatly saving the preparation time for parameter configuration before tasks.

[0023] The telemetry receiving device 4 includes: a low-noise amplifier, a filter switching unit, and a telemetry receiving baseband device connected in series in sequence. The low-noise amplifier amplifies the S-band RF signal received by the directional antenna, and sends the amplified RF signal to the filter switching unit. The filter switching unit calls the frequency-domain adaptive filtering algorithm to solve the filtering of the parameter values according to the operating frequency sent by the ground station monitoring device 3, transforms the input signal into the frequency domain using the fast Fourier transform (FFT), and then processes the spectrum with an interference suppression module to suppress single-frequency and narrowband interference. After completing the RF signal filtering process, it outputs different filtering methods or different parameters under the same filtering method, and then provides them to the real-time curve module to depict the curve trend after filtering, and displays the flight trajectory of the UAV in the track display area. The filter switching unit divides the S-band RF signal between 2200 MHz and 2300 MHz into 5 segments, namely 2200 MHz - 2230 MHz, 2220 MHz - 2250 MHz, 2240 MHz - 2270 MHz, 2260 MHz - 2290 MHz, 2280 MHz - 2300 MHz, with out-of-band rejection ≤ -50 dBc. The filtered RF signal is frequency-converted and demodulated by the telemetry receiving baseband device, and the demodulated data is sent to the network switch, and the data is received and forwarded to the target device through packet switching.

[0024] Refer to Figure 2. The telemetry receiving baseband device includes: a multi-system demodulation module 232 connected in series successively by a frequency agile unit 231, a bit synchronization module 233 that communicates bidirectionally with a decryption machine through a baseband interface, a TPC decoding module 234, a frame synchronization module 235, and a multi-system modulation module 237 and a TPC encoding module 238 connected in series successively by the frequency agile unit 231. They are connected through a PCM simulation module 239 to the above frame synchronization module 235 to form a pulse code modulation PCM self-closed loop, and a telemetry system parameter setting module. Among them, the frequency agile unit 231 processes the S-band RF signal output by the filter switching unit through a low noise amplifier LNA, an automatic gain control AGC, and signal frequency conversion, etc., and outputs in-phase I and quadrature Q data at zero intermediate frequency. Then, the I and Q data of the two paths are combined by diversity, and the output intermediate frequency signal is sent to the multi-system demodulation module 232. Multi-system demodulation is performed sequentially on both the I and Q paths at the same time. The demodulated data is sent to the bit synchronization module 233 for synchronization. If the telemetry data is encrypted, the bit synchronization data is sent to the decryption machine through a dedicated interface for decryption processing, and the decrypted telemetry data is sent to the TPC decoding module 234; if the telemetry data is not encrypted, the bit synchronization data is directly sent to the TPC decoding module 234 for TPC decoding, and then the data is frame synchronized through the frame synchronization module 235. The frame synchronized data is sent to the UAV measurement and control center through a network switch 31 for real-time processing, display, and storage of telemetry data, and the monitoring status data content and data storage management can also be displayed on a portable rugged notebook; at the same time, the PCM simulation module 239 outputs I and Q data and a pulse code modulation / frequency modulation PCM / FM telemetry signal. After TPC encoding by the TPC encoding module 238, it is then FM multi-system modulated by the multi-system modulation module 237. The modulated data 237 is fed back to the frequency agile unit 231 for radio frequency closed-loop self-check of the system. Before the mission, the working state of the device is checked through self-test, effectively improving the reliability of the device.

[0025] In this embodiment, the telemetry parameter setting module 240 sets the working parameters of each module device of the telemetry receiving baseband, calculates the calibration coefficients of each channel, tests and calibrates specific technical indicators: carrier frequency, Doppler change range, code rate, modulation degree, output power, and clutter suppression, etc., compares the test results with the technical indicators, completes the dynamic loading test and dynamic calibration of the telemetry signal encoding, supplies the real-time curve module to automatically draw test curves, generates a test report showing the UAV flight trajectory in the track display area, and prints and outputs.

[0026] The power supply 5 is connected to the antenna pedestal equipment 1, the ground station monitoring equipment 3, and the telemetry receiving equipment 4, providing electrical energy for the entire ground TT&C equipment. The power supply 5 selects the Aiyate DR series wide-temperature lithium battery UPS system, and the rated power is selected as 3KVA / W. In the case of no external power supply or power failure, it can continuously provide power demand for more than 2 hours. At the same time, in a harsh power grid environment, it can provide reliable, stable, and pure electrical energy for the equipment, providing more usage scenarios for the entire ground TT&C system.

[0027] To illustrate the working process of the portable ground telemetry receiving system, combined with the hardware implementation and without loss of generality, taking the unmanned aerial vehicle (UAV) test flight sending a telemetry RF signal as an example, with a signal frequency of 2220 MHz, a working system of PCM-FM, and a telemetry code rate of 1.63874 Mbps, the specific telemetry receiving steps are as follows: The ground station monitoring equipment 3 starts the monitoring thread of the UAV ground telemetry receiving system monitoring software, and performs "one-key" loading settings on the working parameters of all equipment of the portable UAV ground telemetry receiving system. It can also issue the UAV flight orbit plan sent by the UAV measurement and control center through the network interface. The antenna pedestal equipment 1 adjusts the direction of the directional antenna according to the parameters sent by the ground station monitoring equipment 3 and continuously guides the directional antenna. When the capture and tracking of the target are completed, the RF signal received by the directional antenna is sent to the low-noise amplifier. After being amplified by the low-noise amplifier, it is sent to the filter switching unit. The filter switching unit selects the corresponding filter component 2200 MHz - 2230 MHz according to the working frequency 2220 MHz sent by the ground station monitoring equipment 3 and calls the corresponding filter algorithm for filtering processing. The filtered RF signal is sent to the telemetry receiving baseband for frequency conversion and demodulation. When the telemetry information is not encrypted, the formed telemetry data frame is sent to the UAV measurement and control center through a dedicated interface for real-time processing, display, storage of telemetry data, and display of monitoring status data content. When the telemetry information is encrypted, the unencrypted telemetry data frame is sent to the decryption module for decryption processing through a dedicated interface. The decrypted telemetry data frame is sent to the UAV measurement and control center through a dedicated interface for real-time processing, display, storage of telemetry data, and display of monitoring status data content. At the same time, this telemetry data can be transmitted to a rugged notebook through a network switch for data storage management.

[0028] The present invention has been described through specific embodiments. The description of the above embodiments is only used to help understand the equipment of the present invention; at the same time, for those skilled in the art, according to the idea of the present invention, there will be changes in the specific embodiments and application scopes. In summary, the content of this specification should not be construed as a limitation to the present invention.

Claims

1. A portable UAV ground telemetry receiving system, comprising: A telemetry cabinet (2) with universal wheels at the bottom of the cabinet, an antenna feed device (1) matched with the telemetry cabinet (2), a ground station monitoring device (3), a telemetry receiving device (4) and a power supply (5) stored in the cabinet of the telemetry cabinet (2), wherein the telemetry receiving device comprises: a low noise amplifier, a filter switching unit and a telemetry receiving baseband device connected in series, characterized in that: the antenna feed device (1) adjusts the direction of the directional antenna and continuously guides the directional antenna according to the orbit parameters sent by the ground station monitoring device (3), and adopts a single-channel single-pulse system to obtain the telemetry data of the target; the telemetry receiving baseband device adopts: a multi-system demodulation module (232) connected in series with a frequency agile unit (231), and a baseband interface to communicate with a decryption machine. The bit synchronization module (233), TPC decoding module (234), frame synchronization module (235) for bidirectional communication and the multi-system modulation module (237) and TPC encoding module (238) are connected in series via the agile frequency conversion unit (231), and the frame synchronization module (235) is connected via the PCM simulation module (239) to form a pulse code modulation PCM self-closed loop, and a telemetry system parameter setting module, wherein the agile frequency conversion unit (231) processes the S-band radio frequency signal output by the filter switching unit through a low noise amplifier LNA, an automatic gain control AGC and signal frequency conversion to output I and Q data at zero intermediate frequency, and then performs diversity synthesis on the two-way I and Q data, and outputs the intermediate frequency signal to the multi-system demodulation module (232) ), multi-system demodulation is performed on the I and Q paths simultaneously and sequentially, and the demodulated data is sent to the bit synchronization module (233) for synchronization. If the telemetry data is encrypted, the bit synchronization data is sent to the decryption machine through a dedicated interface for decryption processing, and the decrypted telemetry data is sent to the TPC decoding module (234); if the telemetry data is not encrypted, the bit synchronization data is directly sent to the TPC decoding module (234) for TPC decoding, and then the data frame synchronization is performed by the frame synchronization module (235). The frame-synchronized data is sent to the UAV measurement and control center through a network switch for real-time processing, display, and storage of the telemetry data, or the monitoring status data content and data storage management are displayed on a portable reinforced notebook; at the same time, the PCM simulation module (239) outputs The I, Q data and the pulse code modulation / frequency modulation PCM / FM telemetry signal are TPC encoded by the TPC encoding module (238) and then FM multi-system modulated by the multi-system modulation module (237). The modulated data (237) are fed back to the frequency agile unit (231) to perform a system RF closed-loop self-test. The working status of the equipment is checked by a self-test before the mission. After completing the capture and tracking of the target, the received RF signal is sent to the ground station monitoring device (3) through the telemetry receiving link. The ground station monitoring device (3) starts the monitoring thread of the system monitoring software, loads and sets the working parameters of all equipment in a "one-click" manner, and can also issue the UAV flight trajectory plan issued by the UAV measurement and control center through the network interface.The telemetry receiving device (4) selects and invokes the corresponding filtering algorithm according to the working parameters issued by the ground station monitoring device (3) to amplify and filter the RF signal. The processed RF signal is sent to the frequency conversion module integrated in the telemetry receiving baseband device for signal frequency conversion and demodulation. The demodulated telemetry data is sent to the decryption machine for processing through the network port. At the same time, it receives the UAV-related information in real time, estimates the current position of the UAV, and sends the downlink data back to the ground to "graphically" display the working states and parameters of all devices.

2. The portable UAV ground telemetry receiving system according to claim 1, characterized in that: The antenna servo feed equipment includes: a directional antenna fixedly connected to the antenna turntable and the support through an antenna bracket, and a servo system connected to a network switch. The servo system controls the servo control capabilities of the azimuth and elevation degrees of freedom of the antenna turntable according to the parameters issued by the ground station monitoring equipment (3), realizes the accurate pointing to the target, and at the same time reports to the portable rugged notebook system monitoring software to control the working status and fault information of the relevant antenna control unit.

3. The portable unmanned aerial vehicle ground telemetry receiving system according to claim 2, characterized in that: The directional antenna includes: a 1×2 feed network, a 4×4 feed network, and antenna elements. The antenna elements are arranged on a plane of 900 mm * 450 mm to complete the reception of the S-band radio frequency signal sent by the unmanned aerial vehicle.

4. The portable UAV ground telemetry receiving system according to claim 1, wherein: The antenna and feed part of the antenna servo feed equipment realizes the reception of the telemetry signal of the target. The servo part adjusts the steering angle of the antenna element in real time through a digital position regulator. The digital position regulator generates a digital control quantity according to the given control law and sends it to the digital stabilization loop to realize the tracking and pointing of the target. The target angle tracking loop word quantity is formed through the receiving mechanism to control the actuator on the antenna pedestal to drive the antenna to move in the direction of reducing the error until the antenna beam is aligned with the target. After the antenna receives the target signal, when the automatic gain control (AGC) voltage of the received signal, the lock signal indication, and the error voltage meet the given conditions, the antenna enters the self-tracking state to realize the stable and accurate tracking of the target.

5. The portable UAV ground telemetry receiving system according to claim 1, characterized in that: The ground station monitoring equipment includes a portable rugged notebook or a ruggedized three-proof tablet computer that communicates bidirectionally with the network switch. The network switch performs network topology, physical addressing, network monitoring, error checking, frame sequence management, troubleshooting, and configuration on the virtual local area network (VLAN) through a high-speed connection port. The portable rugged notebook deploys system monitoring software and is interconnected with the antenna servo feed equipment (1) and the uninterruptible power supply (5) through the network switch and the telemetry receiving equipment (4). It radiates emission and conducted emission information outward through space and relevant channels, formulates failure criteria according to the anti-radiation index and the performance requirements required by the electronic system, and is ruggedized according to a reasonable safety factor to realize the monitoring and control of each device.

6. The portable unmanned aerial vehicle ground telemetry receiving system according to claim 5, wherein: The system monitoring software includes a user management module, a task management module, a device monitoring module, a macro management module, a data management module, a configuration management module, and a main interface parameter display module. The user management module accepts user login requests. In the logged-in state, all functions of the software are allowed to be used; in the non-logged-in state, the use of task management functions and control functions is restricted. The task management module automatically obtains the task status, running status, aircraft spatial position, and telemetry information reported during the execution of the portable station task, associates them with relevant work plans, realizes the monitoring of the execution status of work plans, displays and records the changes in the execution status of work plans and task plans, judges the abnormal execution of work plans, and completes functions such as abnormal alarm notification, addition, deletion, modification, and interruption. Each task data has playback and statistical functions. The device monitoring module provides comprehensive network monitoring functions, records and displays device operation parameters or status changes, gives alarm prompts for abnormalities, provides human-computer interaction functions such as the display of the portable station operation block diagram, communication link display, and various device units, and ensures the efficient operation of the business system. The macro management module has the ability to control the working parameters of each link device with "one key" and functions of addition, deletion, query, modification. The data management module of the governance platform integrates data integration, component management, data exchange, task scheduling, real-time computing and storage, metadata management, data standard management, data quality management, master data management, data asset management, data security management, and data life cycle management. It queries the target logs, status data, and command data through a certain indexing strategy and has a data maintenance strategy. The data management module obtains the user's configuration data, generates a configuration file, combines it with the existing system architecture, generates application modules according to the configuration file or database definition, and then based on this, makes corresponding data models according to the externally provided data structure definition to expand and meet the needs of various applications. The main interface parameter display module "graphically" displays the working status and parameters of each link device.

7. The portable UAV ground telemetry receiving system according to claim 1, characterized in that: In the telemetry receiving device, the low-noise amplifier amplifies the S-band radio frequency signal sent by the directional antenna, and sends the amplified radio frequency signal to the filter switching unit. The filter switching unit calls the frequency-domain adaptive filtering algorithm to solve the filtering of parameter values according to the working frequency sent by the ground station monitoring device (3), uses the fast Fourier transform FFT to transform the input signal into the frequency domain, and then processes the spectrum with an interference suppression module to suppress single-frequency and narrowband interference. After completing the radio frequency signal filtering process, it outputs different filtering methods or different parameters under the same filtering method, and then provides them to the real-time curve module to depict the curve trend after filtering, and displays the flight trajectory of the UAV in the track display area.

8. The portable UAV ground telemetry receiving system according to claim 7, characterized in that: The filter switching unit divides the S-band RF signal between 2200 MHz and 2300 MHz into 5 segments, namely 2200 MHz - 2230 MHz, 2220 MHz - 2250 MHz, 2240 MHz - 2270 MHz, 2260 MHz - 2290 MHz, and 2280 MHz - 2300 MHz. The out-of-band rejection is ≤ -50 dBc. The filtered RF signal is frequency-converted and demodulated by the telemetry receiving baseband equipment, and the demodulated data is sent to the network switch, and the data is received and forwarded to the target device through packet switching.

9. The portable UAV ground telemetry receiving system according to claim 1, wherein: The power supply (5) is connected to the antenna feed equipment (1), the ground station monitoring equipment (3), and the telemetry receiving equipment (4) to provide electrical energy for the entire ground TT&C equipment. The power supply (5) selects the Aiyate DR series wide-temperature lithium battery UPS system, and the rated power is selected as 3 KVA / W.

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