A combined active and passive microwave satellite spin-scan detection system

Abstract

A passive and active microwave combined satellite spin-scanning detection system provided by an embodiment of the present application relates to the technical field of space microwave remote sensing. The main body of the microwave detection and imaging is connected to the parabolic antenna, and the parabolic antenna is arranged outside the spin satellite platform and fixedly connected to the upper surface of the spin satellite platform through a first folding and retracting structure; the main body of the dual-frequency precipitation radar is integrated inside the spin satellite platform, and the radar antenna is fixedly connected to the side surface of the spin satellite platform through a second folding and retracting structure; the spin satellite platform spins at a preset spin period to drive the parabolic antenna and the radar antenna to perform a 360° wide-angle conical scan of the ground to complete ground observation. The present application integrates passive microwave, active radar and satellite spin platform, and uses the rotation of the spin satellite platform to drive the passive microwave and active radar to perform a 360° wide-angle conical scan of the ground, which greatly reduces the mass, volume, power consumption and cost of the whole satellite while ensuring the observation accuracy.

Description

Technical Field

[0001] This application relates to the technical field of space microwave remote sensing, and in particular, to a combined active and passive microwave satellite spin-scanning detection system. Background Art

[0002] In the field of satellite remote sensing, the combined observation system of active radar and passive microwave radiometer has become an important means to improve the monitoring accuracy. Among foreign typical cases, the Global Precipitation Measurement Core (GPM) satellite led by the National Aeronautics and Space Administration (NASA) of the United States (launched in 2014) is the most representative. It is equipped with a Ku / Ka dual-frequency precipitation radar and a microwave imager. By obtaining the vertical structure of precipitation through the active radar and combining with the passive microwave wide-area observation, high-precision global precipitation products are generated, greatly improving the ability to predict extreme weather.

[0003] However, in the existing combined observation system, the selected microwave imager uses an internally integrated rotating mechanism to drive the microwave antenna to rotate, and the precipitation radar requires 128 transceiver units to form a phased array system. An observation strip is formed through cross-track phased array electronic scanning. In such a combined observation mode, both the microwave imager and the precipitation radar require complex scanning mechanisms that operate independently, which not only increases the complexity of the combined observation system but also increases the weight of the combined observation system, resulting in an increase in the power consumption of the entire system and an increase in the observation cost. Summary of the Invention

[0004] In view of this, the purpose of this application is to provide at least a combined active and passive microwave satellite spin-scanning detection system. This application integrates passive microwave, active radar, and the satellite spin platform. The rotation of the spin satellite platform drives the passive microwave and the active radar to perform a 360° wide-angle conical scan of the ground, simplifying the system structure and the total system weight while ensuring the observation accuracy, and reducing the system power consumption and the observation cost.

[0005] This application mainly includes the following aspects:

[0006] In the first aspect, the embodiments of this application provide

[0007] A combined active and passive microwave satellite spin-scanning detection system, which includes a spinning satellite platform, a combined microwave detection imager, and a dual-frequency precipitation radar. The combined microwave detection imager includes a parabolic antenna and a microwave detection imaging main body. The dual-frequency precipitation radar includes a dual-frequency precipitation radar main body and a radar antenna. The microwave detection imaging main body is connected to the parabolic antenna, and the microwave detection imaging main body is integrated inside the spinning satellite platform. The parabolic antenna is arranged outside the spinning satellite platform and is fixedly connected to the upper surface of the spinning satellite platform through a first folding and retracting structure. The dual-frequency precipitation radar main body is integrated inside the spinning satellite platform, and the radar antenna is fixedly connected to the side surface of the spinning satellite platform through a second folding and retracting structure. The spinning satellite platform spins at a preset spin period to drive the parabolic antenna and the radar antenna to perform a 360° wide-angle conical scan of the ground to complete ground observation.

[0008] In a possible implementation manner, the combined microwave detection imager adopts a multi-polarization, multi-frequency, and multi-channel design. The microwave detection imaging main body includes multiple signal processing channels, and the frequency bands covered by the multiple signal processing channels include 6.8 GHz (gigahertz), 10.7 GHz, 18.7 GHz, 23.8 GHz, 31.4 GHz, 37 GHz, 50 - 60 GHz, 89 GHz, 118 GHz, 166 GHz, and 183 GHz. The combined microwave detection imager supports multi-polarization modes, and the multi-polarization modes include vertical polarization, horizontal polarization, and full polarization. The swath width covered by the combined microwave detection imager is greater than or equal to 1500 kilometers.

[0009] In a possible implementation manner, different signal processing channels of the combined microwave detection imager correspond to different application modes, and the corresponding channel configuration information between different signal processing channels is different. The channel configuration information includes at least the center frequency and the polarization mode.

[0010] In a possible implementation manner, the parabolic antenna adopts an offset feed design, and all the frequency bands covered by the combined microwave detection imager form a feed array at the corresponding focus of the parabolic antenna, so that all the frequency bands covered by the combined microwave detection imager share the same reflecting surface.

[0011] In a possible implementation, among the multiple feeds corresponding to the feed array, the 6.8 GHz band and the 10.7 GHz band share one feed, the 18.7 GHz band, the 23.8 GHz band, the 31.4 GHz band, and the 37 GHz band share one feed, the 50 - 60 GHz band shares one feed, the 89 GHz band and the 118 GHz band share one feed, the 166 GHz band and the 183 GHz band share one feed. The microwave detection and imaging main body includes a receiver module corresponding to each feed and a microwave numerical control unit. The feed is connected to the microwave numerical control unit through the receiver module corresponding to the feed.

[0012] In a possible implementation, the receiver module includes a receiver front end and a medium - low frequency receiver. Among them, when the active - passive microwave combined satellite spin - scan detection system is in the on - orbit working state: the parabolic antenna receives the microwave radiation signal corresponding to the observation target and transmits it to multiple receiver modules through the feed array; for each receiver module: the receiver front end down - converts the microwave radiation signal to an intermediate - frequency signal and performs pre - amplification processing, and transmits the processed signal to the medium - low frequency receiver. The medium - low frequency receiver sequentially performs signal amplification, square - law detection, low - frequency amplification, and integration processing on the processed signal, and transmits the processed signal to the microwave numerical control unit; the microwave numerical control unit performs data analysis on the signals transmitted by each receiver module, determines the corresponding microwave observation results, and sends them to the ground control center through the spin satellite platform.

[0013] In a possible implementation, the dual - frequency precipitation radar main body includes a signal processing unit, a Ka / Ku up - down conversion unit, a Ka / Ku power amplification unit, a Ka / Ku waveguide network, and a slot antenna. Among them, the signal processing unit receives the radar measurement and control instructions corresponding to the spin satellite platform, and generates the transmitted intermediate - frequency signal required for precipitation according to the radar measurement and control instructions, and sends the transmitted intermediate - frequency signal to the Ka / Ku up - down conversion unit; the Ka / Ku up - down conversion unit up - converts the transmitted intermediate - frequency signal to the Ku transmitted radio - frequency signal corresponding to the Ku band and the Ka transmitted radio - frequency signal corresponding to the Ka band respectively; the Ka / Ku power amplification unit amplifies the Ku transmitted radio - frequency signal and the Ka transmitted radio - frequency signal respectively to obtain the Ku transmitted power signal and the Ka transmitted power signal; the Ka / Ku waveguide network and the slot antenna perform weighted combination on the Ku transmitted power signal and the Ka transmitted power signal, and realize outward radiation through the radar antenna.

[0014] In a possible implementation, the radar antenna receives the radar observation signal corresponding to the observation target and sends it to the Ka / Ku waveguide network and the slot antenna; the Ka / Ku waveguide network and the slot antenna split the radar observation signal to obtain the Ku received RF signal and the Ka received RF signal and send them to the Ka / Ku up / down conversion unit; the Ka / Ku up / down conversion unit respectively down-converts the Ku received RF signal into the Ku received intermediate frequency signal and down-converts the Ka received RF signal into the Ka received intermediate frequency signal; the signal processing unit collects the Ku received intermediate frequency signal and the Ka received intermediate frequency signal, and performs pulse compression processing on the Ku received intermediate frequency signal and the Ka received intermediate frequency signal to obtain the precipitation echo scientific data in the Ku / Ka band and transmits it back to the ground control center through the spin satellite platform.

[0015] In a possible implementation, when the active and passive microwave combined satellite spin scan detection system is in the transmitting state, the parabolic antenna is in the retracted state through the first folding and retracting structure; when the active and passive microwave combined satellite spin scan detection system is in the on-orbit working state, the parabolic antenna is in the deployed state through the first folding and retracting structure.

[0016] In a possible implementation, when the active and passive microwave combined satellite spin scan detection system is in the transmitting state, the radar antenna is in the retracted state through the second folding and retracting structure; when the active and passive microwave combined satellite spin scan detection system is in the on-orbit working state, the radar antenna is in the deployed state through the second folding and retracting structure.

[0017] An active and passive microwave combined satellite spin scan detection system provided by an embodiment of the present application relates to the technical field of space microwave remote sensing. The microwave detection imaging main body is connected to the parabolic antenna, and the parabolic antenna is arranged outside the spin satellite platform and fixedly connected to the upper surface of the spin satellite platform through the first folding and retracting structure; the dual-frequency precipitation radar main body is integrated inside the spin satellite platform, and the radar antenna is fixedly connected to the side surface of the spin satellite platform through the second folding and retracting structure; the spin satellite platform spins at a preset spin period to drive the parabolic antenna and the radar antenna to perform a 360° wide-angle conical scan of the ground to complete ground observation. The present application integrates passive microwave, active radar and satellite spin platform, and uses the rotation of the spin satellite platform to drive the passive microwave and active radar to perform a 360° wide-angle conical scan of the ground, which greatly reduces the mass, volume, power consumption and cost of the whole satellite while ensuring the observation accuracy.

[0018] In order to make the above objects, features and advantages of the present application more obvious and understandable, the following specifically enumerates preferred embodiments and, in conjunction with the accompanying drawings, makes a detailed description as follows. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] To more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings required for the embodiments. It should be understood that the following drawings only show some embodiments of the present application and should not be regarded as limiting the scope. For those of ordinary skill in the art, without creative efforts, other related drawings can also be obtained based on these drawings.

[0020] Figure 1 Shows a schematic structural diagram of a combined active and passive microwave satellite spin-scanning detection system provided by an embodiment of the present application;

[0021] Figure 2 Shows an overall state configuration diagram of a combined active and passive microwave satellite spin-scanning detection system provided by an embodiment of the present application when in the emission state;

[0022] Figure 3 Shows an overall state configuration diagram of a combined active and passive microwave satellite spin-scanning detection system provided by an embodiment of the present application when in the in-orbit working state;

[0023] Figure 4 Shows a schematic structural diagram of a comprehensive microwave detection imager provided by an embodiment of the present application;

[0024] Figure 5 Shows a schematic structural diagram corresponding to the main body of a dual-frequency precipitation radar provided by an embodiment of the present application;

[0025] Figure 6 Shows a schematic diagram of the observation strip of a combined active and passive microwave satellite spin-scanning detection system provided by an embodiment of the present application. Detailed implementation manners

[0026] To make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the following will clearly and completely describe the technical solutions in the embodiments of the present application in combination with the drawings in the embodiments of the present application. It should be understood that the drawings in the present application only serve the purposes of illustration and description and are not used to limit the protection scope of the present application. Additionally, it should be understood that the schematic drawings are not drawn to actual scale. The flowcharts used in the present application illustrate the operations implemented according to some embodiments of the present application. It should be understood that the operations in the flowchart may not be implemented in sequence, and steps without logical context relationships may be reversed or implemented simultaneously. Furthermore, those skilled in the art can add one or more other operations to the flowchart or remove one or more operations from the flowchart under the guidance of the content of the present application.

[0027] In addition, the described embodiments are only a part of the embodiments of the present application, rather than all embodiments. The components of the embodiments of the present application described and illustrated in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the present application claimed, but only represents the selected embodiments of the present application. All other embodiments obtained by those skilled in the art based on the embodiments of the present application without creative efforts fall within the scope of protection of the present application.

[0028] Satellite remote sensing is the only observational means capable of monitoring the process of tropical storms. Using satellite remote sensing to monitor the formation, movement, and evolution process of tropical storms is of great significance for disaster early warning, monitoring, and reducing the impact of disasters. Among them, microwaves and millimeter waves can penetrate cloud and rain atmospheres, provide information inside clouds, and effectively monitor the large-scale typhoon structure and its changes, and can also monitor the whole process of the occurrence, development, and dissipation of typhoons in real time.

[0029] Atmospheric temperature, humidity, precipitation, air pressure, and macro-microscopic parameters of clouds including cloud path, ice-water content, particle size, etc. are important atmospheric physical parameters, which are of great significance for accurate weather forecasting, earth science research such as climate and water cycle, energy cycle, etc., and are also key elements for achieving accurate and timely battlefield meteorological and ocean environmental support.

[0030] Spaceborne microwave radiometers belong to passive microwave remote sensors and detect by receiving electromagnetic radiation or reflection from ground targets. Compared with infrared and visible light remote sensors, microwave radiometers have the advantages of longer wavelengths, stronger penetration ability, and can work all day and all weather. They are particularly suitable for observing geophysical parameters. They can not only be applied to aspects such as ocean environmental monitoring, atmospheric and meteorological observations, agricultural monitoring, geological exploration, and military reconnaissance, but also be used in fields such as terminal guidance of missiles, radio astronomy, and medical pathology research. Microwave radiometers can perform amplitude-phase, polarization, and coherent reception, and can perform flexible signal processing to obtain more useful information. Compared with active remote sensors, microwave radiometers have the characteristics of low power consumption, small volume, light weight, and stable and reliable operation.

[0031] As the core payload of the active and passive microwave combined detection satellite spin-scanning observation system, the precipitation radar uses Ku and Ka dual bands to observe the three-dimensional drop spectrum characteristics of atmospheric precipitation such as typhoons, heavy rains, and heavy snows. Its measurement parameters are independent of background radiation and directly related to precipitation. It can invert more accurate precipitation intensity than passive remote sensing, and can also obtain other rich precipitation information such as precipitation type and precipitation layer height, which can improve the space-based precipitation measurement ability, provide the three-dimensional structure of precipitation such as typhoons, heavy rains, and heavy snows, deepen the understanding of storm structure, cloud microphysics and mesoscale weather system dynamics, and improve the accuracy of meteorological forecasts and predictions such as precipitation.

[0032] In the field of satellite remote sensing, the combined observation system of active radar and passive microwave radiometer has become an important means to improve monitoring accuracy. Among foreign typical cases, the GPM satellite led by NASA (launched in 2014) is the most representative. It is equipped with Ku / Ka dual-frequency precipitation radar and microwave imager. By obtaining the precipitation vertical structure through active radar and combining with passive microwave wide-area observation, it generates global high-precision precipitation products, that is, calibrating the radiometer inversion algorithm through radar high-precision data, which greatly improves the extreme weather prediction ability.

[0033] However, for the existing combined observation system, the selected microwave imager uses an internal integrated rotating mechanism to drive the microwave antenna to rotate, and the precipitation radar requires 128 transceiver units to form a phased array system, and forms an observation strip through cross-track phased array electronic scanning. In such a combined observation mode, both the microwave imager and the precipitation radar require complex scanning mechanisms that operate independently, which not only increases the complexity of the combined observation system, but also increases the weight of the combined observation system, which makes the power consumption of the entire system increase and the observation cost increase.

[0034] Based on this, the embodiment of the present application provides an active and passive microwave combined satellite spin-scanning detection system. By integrating the passive microwave, active radar and satellite spin platform, the rotation of the spin satellite platform drives the passive microwave and active radar to perform 360° wide-angle conical scanning of the ground, which greatly reduces the mass, volume, power consumption and cost of the whole satellite while ensuring the observation accuracy, as follows:

[0035] Please refer to Figure 1 , Figure 1 which shows the structural schematic diagram of an active and passive microwave combined satellite spin-scanning detection system provided by the embodiment of the present application. As Figure 1As shown in the figure, the active and passive microwave combined satellite spin-scanning detection system provided by the embodiments of the present application includes a payload 1 and a spin satellite platform 2. The payload 1 includes a comprehensive microwave detection imager 11 and a dual-frequency precipitation radar 12. The spin satellite platform 2 includes a data management and data transmission subsystem 21, a thermal control subsystem 22, an energy and power distribution subsystem 23, a propulsion subsystem 24, an attitude and orbit control subsystem 25, and a structure and mechanism subsystem 26.

[0036] Among them, the comprehensive microwave detection imager 11 and the dual-frequency precipitation radar 12 respectively perform data interaction with the data management and data transmission subsystem 21.

[0037] Please refer to Figure 2 , Figure 2 shows the overall state configuration diagram of a main and passive microwave combined satellite spin-scanning detection system provided by the embodiments of the present application when in the launch state. Please refer to Figure 3 , Figure 3 shows the overall state configuration diagram of a main and passive microwave combined satellite spin-scanning detection system provided by the embodiments of the present application when in the in-orbit working state. As Figure 2 and Figure 3 shown, the comprehensive microwave detection imager 11 includes a parabolic antenna 110 and a microwave detection imaging main body 111. The dual-frequency precipitation radar 12 includes a dual-frequency precipitation radar main body (not shown in the figure) and a radar antenna 120.

[0038] The microwave detection imaging main body 111 is connected to the parabolic antenna 110 (not shown in the figure). The microwave detection imaging main body 111 is integrated inside the spin satellite platform 2. The parabolic antenna 110 is arranged outside the spin satellite platform 2 and is fixedly connected to the upper surface of the spin satellite platform 2 through a first folding and retracting structure 3.

[0039] The dual-frequency precipitation radar main body is integrated inside the spin satellite platform 2. The radar antenna 120 is connected to the dual-frequency precipitation radar main body. The radar antenna 120 is fixedly connected to the side surface of the spin satellite platform 2 through a second folding and retracting structure 4.

[0040] The spin satellite platform 2 spins at a preset spin period to drive the parabolic antenna 110 and the radar antenna 120 to perform a 360° wide-angle conical scan of the ground to complete ground observation.

[0041] In a preferred embodiment, the radar antenna 120 includes a first radar antenna 1201 and a second radar antenna 1202. The first radar antenna 1201 and the second radar antenna 1202 are fixedly connected to the side surface of the spin satellite platform 2 through their respective corresponding second folding and retracting structures 4, and the first radar antenna 1201 and the second radar antenna 1202 are arranged oppositely.

[0042] In a preferred embodiment, as Figure 2As shown, when the active and passive microwave combined satellite spin-scanning detection system is in the transmitting state, the parabolic antenna 110 is in a retracted state through the first folding and retracting structure 3, and the radar antenna 120 is in a retracted state through the second folding and retracting structure 4.

[0043] As Figure 3 shown, when the active and passive microwave combined satellite spin-scanning detection system is in the on-orbit working state, the parabolic antenna 110 is in an unfolded state through the first folding and retracting structure 3, and the radar antenna 120 is in an unfolded state through the second folding and retracting structure 4.

[0044] In a preferred embodiment, the active and passive microwave combined satellite spin-scanning detection system provided in the present application realizes the scanning observation of the payload through the rotation of the entire spin satellite platform 2. The preset spin period corresponding to the spin satellite platform 2 can be set to 2 to 4 seconds per revolution.

[0045] In a specific embodiment, in the spin satellite platform 2:

[0046] For the power and distribution subsystem 23, body-mounted solar panels are arranged on the side of the spin satellite platform 2 to obtain operating energy, so as to realize the power supply and distribution of the spin satellite platform 2 and the balance of operating energy.

[0047] For the attitude and orbit control subsystem 25, the scanning azimuth corresponding to the payload 1 is determined through a gyroscope and an optical auxiliary camera. A star map is taken every revolution through a gyroscope, momentum wheels, magnetometers, optical auxiliary cameras, etc. The earth pointing is corrected by combining gyroscope data. Satellite positioning is realized through GPS, and attitude control is realized through magnetometers, etc.

[0048] For the propulsion subsystem 24, the spin satellite platform 2 is made to spin at a preset spin period by configuring an electric thruster or other thrusters.

[0049] For the data management and data transmission subsystem 21, it is used for data interaction with the integrated microwave detection imager, dual-frequency precipitation radar, and ground control center.

[0050] In a preferred embodiment, the integrated microwave detection imager adopts a multi-polarization, multi-frequency, and multi-channel design. The microwave detection imaging main body includes multiple signal processing channels. The frequency bands covered by the multiple signal processing channels include 6.8 GHz (gigahertz), 10.7 GHz, 18.7 GHz, 23.8 GHz, 31.4 GHz, 37 GHz, 50 - 60 GHz (oxygen absorption band), 89 GHz, 118 GHz, 166 GHz, and 183 GHz (water vapor absorption band).

[0051] The integrated microwave detection imager 11 supports multi-polarization modes, and the multi-polarization modes include vertical polarization, horizontal polarization, and full polarization.

[0052] The integrated microwave sounder imager 11 integrates the functions of atmospheric vertical sounding and surface imaging. Driven by the spin of the spin satellite platform 2, the parabolic antenna 110 corresponding to the integrated microwave sounder imager 11 performs full-field continuous scanning, so that the swath width covered by the integrated microwave sounder imager 11 is greater than or equal to 1500 kilometers.

[0053] In a preferred embodiment, different signal processing channels of the integrated microwave sounder imager correspond to different application modes, and the channel configuration information corresponding to different signal processing channels is different. The channel configuration information at least includes the center frequency and the polarization mode.

[0054] As shown in Tables 1 to 3, Tables 1 to 3 are the channel configuration and channel application tables of the integrated microwave sounder imager.

[0055] Table 1

[0056]

[0057] Table 2

[0058]

[0059] Table 3

[0060]

[0061] Preferably, as shown in Table 1, the channel configuration information corresponding to 36 signal processing channels is statistically shown. Taking serial number 1 as an example, the center frequency corresponding to the signal processing channel is 6.8 GHz, the polarization mode is dual polarization, and its channel is applied to sea surface temperature observation.

[0062] In a preferred embodiment, the parabolic antenna 110 adopts an offset feed design, and all frequency bands covered by the integrated microwave sounder imager 11 form a feed array at the focus corresponding to the parabolic antenna 110, so that all frequency bands covered by the integrated microwave sounder imager 11 share the same reflector.

[0063] In another preferred embodiment, among the multiple feeds corresponding to the feed array, the 6.8 GHz frequency band and the 10.7 GHz frequency band share one feed, the 18.7 GHz frequency band, the 23.8 GHz frequency band, the 31.4 GHz frequency band and the 37 GHz frequency band share one feed, the 50 - 60 GHz frequency band shares one feed, the 89 GHz frequency band and the 118 GHz frequency band share one feed, and the 166 GHz frequency band and the 183 GHz frequency band share one feed.

[0064] The microwave sounding imaging main body 111 includes a receiver module corresponding to each feed and a microwave numerical control unit. The feed is connected to the microwave numerical control unit through the receiver module corresponding to the feed.

[0065] Please refer to Figure 4 , Figure 4 which shows a schematic structural diagram of a comprehensive microwave detection imager provided by an embodiment of the present application. As Figure 4 shown, the comprehensive microwave detection imager provides a total of feeds S1 to S5. Among them, the 6.8 GHz band and the 10.7 GHz band share feed S1, the 18.7 GHz band, the 23.8 GHz band, the 31.4 GHz band, and the 37 GHz band share feed S2, the 50 - 60 GHz band shares feed S3, the 89 GHz band and the 118 GHz band share feed S4, and the 166 GHz band and the 183 GHz band share feed S5.

[0066] The microwave detection imaging main body 111 includes a receiver module corresponding to each feed and a microwave numerical control unit. Each feed is respectively connected to the microwave numerical control unit through the receiver module corresponding to the feed. Preferably, the receiver module includes a receiver front end and a medium - low frequency receiver.

[0067] As Figure 4 shown, the receiver module corresponding to feed S1 includes a receiver front end A1 supporting the 6.8 GHz / 10.7 GHz band and an intermediate frequency receiver B1. Feed S1 is connected to the microwave numerical control unit through the receiver front end A1 and the intermediate frequency receiver B1.

[0068] The receiver module corresponding to feed S2 includes a receiver front end A2 supporting the 18.7 GHz / 23.8 GHz / 31.4 GHz / 37 GHz band and an intermediate frequency receiver B2. Feed S2 is connected to the microwave numerical control unit through the receiver front end A2 and the intermediate frequency receiver B1.

[0069] The receiver module corresponding to feed S3 includes a receiver front end A3 supporting the 50 - 60 GHz band and a 15 - channel intermediate frequency receiver B3. Feed S3 is connected to the microwave numerical control unit through the receiver front end A3 and the 15 - channel intermediate frequency receiver B3.

[0070] The receiver module corresponding to feed S4 includes a receiver front end A4 supporting the 118 GHz band and an 8 - channel intermediate frequency receiver B4, and a receiver front end A5 supporting the 89 GHz band and an intermediate frequency receiver B5. Among them, after passing through a duplexer, feed S3 is connected to the microwave numerical control unit through the receiver front end A4 and the 8 - channel intermediate frequency receiver B4, and is also connected to the microwave numerical control unit through the receiver front end A5 and the intermediate frequency receiver B5.

[0071] The receiver module corresponding to the feed S5 includes a receiver front-end A6 supporting the 183 GHz band and a 5-channel intermediate-frequency receiver B6, and a receiver front-end A7 supporting the 166 GHz band and an intermediate-frequency receiver B7. Among them, after passing through the duplexer, the feed S5 is connected to the microwave digital control unit through the receiver front-end A6 and the 5-channel intermediate-frequency receiver B4, and is also connected to the microwave digital control unit through the receiver front-end A7 and the intermediate-frequency receiver B7.

[0072] Preferably, the microwave detection and imaging main body 111 further includes a power supply unit and a calibration unit (not shown in the figure). The power supply unit is responsible for supplying power to the entire microwave detection imager. The calibration method corresponding to the calibration unit is to perform out-of-aperture calibration of the feed with a normal-temperature calibration blackbody and the cosmic cold sky background temperature as reference sources. Specifically, the normal-temperature calibration blackbody and the cosmic cold sky background respectively provide stable high-temperature and low-temperature reference sources for the integrated microwave detection imager.

[0073] In a preferred embodiment, when the active and passive microwave combined satellite spin-scan detection system is in the in-orbit working state:

[0074] The parabolic antenna 110 receives the microwave radiation signal corresponding to the observation target and transmits it to multiple receiver modules through the feed array. For each receiver module: the receiver front-end down-converts the microwave radiation signal to an intermediate-frequency signal and performs pre-amplification processing, and transmits the processed signal to the intermediate- and low-frequency receiver. The intermediate- and low-frequency receiver sequentially performs signal amplification, square-law detection, low-frequency amplification and integration processing on the processed signal, and transmits the processed signal to the microwave digital control unit. The microwave digital control unit performs data analysis on the signals transmitted by each receiver module, determines the corresponding microwave observation results and sends them to the ground control center through the spin satellite platform.

[0075] Preferably, the microwave digital control unit is used to digitize and process the received signals, and control the entire integrated microwave detection imager to work stably and orderly according to the processing results, and communicate with the spin satellite platform through the CAN bus. Specifically, the specific functions of the microwave digital control unit are as follows:

[0076] 1) Collect and quantize the signals or data transmitted by each receiver module to obtain microwave observation results, and inversely adjust the channel gains inside each receiver module according to the microwave observation results, so that the channels inside each receiver module work in the best state.

[0077] 2) Receive the channel power-on and power-off remote sensing instructions sent by the ground control center or the spin satellite platform to control the power-on and power-off operations of each channel inside each receiver module.

[0078] 3) Receive the remote sensing command of the working state sent by the ground control center or the spin satellite platform, and after decoding, control the working state of the entire integrated microwave detection imager according to the remote sensing command of the working state.

[0079] 4) Encode and integrate the microwave observation results, and directly send them to the ground control center according to the agreed data format or transmit them to the ground control center through the spin satellite platform. After receiving the microwave observation results, the ground control center also analyzes them according to the agreed data format.

[0080] In a preferred embodiment, please refer to Figure 5 , Figure 5 which shows the structural schematic diagram corresponding to a dual-frequency precipitation radar main body provided by the embodiment of the present application. As Figure 5 shown, the dual-frequency precipitation radar main body includes a signal processing unit 1211, a Ka / Ku up and down conversion unit 1212, a Ka / Ku power amplification unit 1213, a Ka / Ku waveguide network and slot antenna 1214, and a power supply and distribution unit 1215.

[0081] Among them, the power supply and distribution unit 1215 supplies power to the entire dual-frequency precipitation radar.

[0082] Preferably, the working process of the dual-frequency precipitation radar is divided into two processes: remote sensing command processing and observation signal processing. As Figure 5 shown, the remote sensing command processing process corresponding to the dual-frequency precipitation radar includes:

[0083] The signal processing unit 1211 receives the radar measurement and control command corresponding to the spin satellite platform 2, generates the transmitted intermediate frequency signal required for precipitation according to the radar measurement and control command, and sends the transmitted intermediate frequency signal to the Ka / Ku up and down conversion unit 1212. The Ka / Ku up and down conversion unit 1212 respectively up-converts the transmitted intermediate frequency signal to the Ku transmitted radio frequency signal corresponding to the Ku band and the Ka transmitted radio frequency signal corresponding to the Ka band. The Ka / Ku power amplification unit 1213 respectively amplifies the Ku transmitted radio frequency signal and the Ka transmitted radio frequency signal to obtain the Ku transmitted power signal and the Ka transmitted power signal. The Ka / Ku waveguide network and slot antenna 1214 perform weighted combination on the Ku transmitted power signal and the Ka transmitted power signal, and realize outward radiation through the radar antenna.

[0084] As Figure 5 shown, the observation signal processing process corresponding to the dual-frequency precipitation radar includes:

[0085] The radar antenna 120 receives the radar observation signals corresponding to the observed targets and sends them to the Ka / Ku waveguide network and slot antenna 1214. The Ka / Ku waveguide network and slot antenna 1214 perform power division on the radar observation signals to obtain the Ku received RF signal and the Ka received RF signal, and send them to the Ka / Ku up / down conversion unit 1212. The Ka / Ku up / down conversion unit 1212 respectively down-converts the Ku received RF signal into the Ku received intermediate frequency signal and down-converts the Ka received RF signal into the Ka received intermediate frequency signal. The signal processing unit 1211 collects the Ku received intermediate frequency signal and the Ka received intermediate frequency signal, and performs pulse compression processing on the Ku received intermediate frequency signal and the Ka received intermediate frequency signal to obtain the precipitation echo scientific data in the Ku / Ka band and transmits it back to the ground control center through the spin satellite platform 2.

[0086] The advantages of this application compared with the prior art are as follows:

[0087] 1) The active and passive microwave combined satellite spin scan detection system provided by this application, through the integrated design of the payload and the spin satellite platform, removes the rotating mechanism in the rotating mechanism of the traditional passive microwave radiometer and the phased array system formed by 128 transceiver units in the traditional precipitation radar, and can achieve the optimal utilization rate of the whole satellite resources, greatly reducing the mass, volume and power consumption of the whole satellite. The active and passive microwave combined satellite spin scan detection system provided by this application is estimated to have a whole satellite mass of less than 240 kg (the mass of the same type of satellite provided by the prior art requires several tons), and the power consumption is less than 300 W, greatly reducing the satellite development and launch costs.

[0088] 2) The active and passive microwave combined satellite spin scan detection system provided by this application drives the integrated microwave detection imager (passive payload) and the dual-frequency precipitation radar (active payload) to complete a 360° wide-angle conical scan of the ground through the spin of the spin satellite platform, greatly expanding the observation range of the active and passive payloads. Specifically, the observation range has been expanded from the original partial strips to a complete circular strip, increasing the observation range and the resampling area, and greatly improving the observation efficiency.

[0089] 3) The active and passive microwave combined satellite spin scan detection system provided by this application, due to removing the rotating mechanism carried in the traditional microwave detection imager, avoids world-class technical problems such as the failure of the rotating mechanism and the conductive slip ring in orbit of the active and passive microwave combined satellite spin scan detection system, and can greatly extend the in-orbit service life of the whole satellite and improve the reliability of the whole active and passive microwave combined satellite spin scan detection system compared with the current state.

[0090] 4) The spaceborne precipitation radar provided by the prior art requires 128 transceiver units to form a phased array system. An observation strip is formed through cross-track phased array electronic scanning. The phase scanning angular range is only dozens of degrees, and the observation strip is only 245 km. Moreover, due to the scanning system of the traditional spaceborne precipitation radar being cross-track scanning, the change in the incident angle will cause observation errors. The dual-frequency precipitation radar in the active-passive microwave combined satellite spin scanning detection system provided by this application only needs to be simplified to one transceiver for each frequency point, greatly reducing the weight, power consumption, and cost of the precipitation radar.

[0091] 5) Please refer to Figure 6 , Figure 6 which shows a schematic diagram of the observation strip of an active-passive microwave combined satellite spin scanning detection system provided by an embodiment of this application. As Figure 6 shown, the dual-frequency precipitation radar in the active-passive microwave combined satellite spin scanning detection system provided by this application and the integrated microwave detection imager in the passive system both perform conical scanning, and the incident angle remains fixed. A complete circular strip is formed on the ground. Among them, the large circle is the observation strip of the integrated microwave detection imager, and the small circle is the observation strip of the dual-frequency precipitation radar. Thus, it can be seen that the system provided by this application greatly increases the scanning observation range, improves the observation efficiency, and is more conducive to improving the accuracy of active-passive joint observation inversion.

[0092] 6) The integrated microwave detection imager provided by this application includes all the classic channel configurations of traditional atmospheric detectors, dual-polarization microwave imagers, and full-polarization microwave imagers, realizing an integrated design of imaging and detection. At the same time, it includes atmospheric, precipitation, sea surface and ocean dynamics environment, and land surface detection. Multi-channel and multi-element simultaneous observation and joint inversion will greatly improve the observation accuracy, realize the integrated monitoring of ocean and atmosphere remote sensing, and expand the application scope.

[0093] 7) The scanning system of the traditional passive microwave detector is a cross-track system, and the change in the incident angle will also cause data inversion errors. After the detector and imager are combined to form an integrated microwave detection imager in the active-passive microwave combined satellite spin scanning detection system provided by this application, the conical scanning is used for the scanning system, so that the incident angle remains unchanged, further improving the detection accuracy. At the same time, since the integrated microwave detection imager integrating the detector and imager uses a large-aperture parabolic antenna, the spatial resolution of the atmospheric vertical detection channel is greatly improved, and the observation performance of the integrated microwave detection imager is further enhanced.

[0094] 8) After the overall satellite cost is greatly reduced, multiple satellites can be networked to form an observation constellation, greatly improving the observation time and spatial resolution. It can realize high-frequency real-time detection of disastrous weather such as typhoons and basin-wide precipitation and its change process, fill the gap in the world's high-frequency active-passive microwave joint detection in the cloud and rain area, and greatly improve the forecast and early warning capabilities of disasters including typhoon path intensity forecasting.

[0095] 9) The active and passive microwave combined satellite spin scan detection system provided by this application can achieve 24-hour global all-weather three-dimensional atmospheric temperature and humidity detection, precipitation and water vapor detection, sea surface temperature, sea ice detection, typhoon path intensity forecasting and early warning, marine dynamic environment detection such as sea surface wind speed and direction, and land surface vegetation index detection, etc. By combining active radar and passive microwave remote sensing, it can penetrate clouds and achieve all-weather and all-time precipitation monitoring, especially outstanding in extreme weather such as typhoons and heavy rains, and can widely serve multiple industries such as meteorology, ocean, agriculture, transportation (low-altitude economy, civil aviation, shipping, etc.), financial insurance, and electricity, with broad application prospects, important social value, and huge commercial value.

[0096] Those skilled in the art can clearly understand that for the convenience and simplicity of description, the specific working processes of the systems and devices described above can refer to the corresponding processes in the foregoing method embodiments and will not be elaborated here. In the several embodiments provided in this application, it should be understood that the disclosed systems, devices, and methods can be implemented in other ways. The device embodiments described above are only illustrative. For example, the division of the units is only a logical function division, and there can be other division methods in actual implementation. Another example is that multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the displayed or discussed couplings or direct couplings or communication connections to each other can be through some communication interfaces, and the indirect couplings or communication connections of the devices or units can be in electrical, mechanical, or other forms.

[0097] The units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they can be located in one place or distributed to multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0098] In addition, in each embodiment of this application, the functional units can be integrated in one processing unit, or each unit can exist physically alone, or two or more units can be integrated in one unit.

[0099] When the above-mentioned functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a non-volatile computer-readable storage medium executable by a processor. Based on such an understanding, the technical solution of the present application, in essence, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in various embodiments of the present application. The foregoing storage medium includes: various media such as USB flash drives, mobile hard disks, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical discs that can store program codes.

[0100] The above is only the specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present application can easily think of changes or substitutions, which should all be covered by the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A combined active and passive microwave satellite spin-scan detection system, characterized in that, The active and passive microwave combined satellite spin-scanning detection system includes a spin satellite platform, a comprehensive microwave detection imager, and a dual-frequency precipitation radar. The comprehensive microwave detection imager includes a parabolic antenna and a microwave detection imaging main body. The dual-frequency precipitation radar includes a dual-frequency precipitation radar main body and a radar antenna. The scanning incident angles of the comprehensive microwave detection imager and the dual-frequency precipitation radar are fixed and unchanged. The microwave detection imaging main body is connected to the parabolic antenna. The microwave detection imaging main body is integrated inside the spin satellite platform. The parabolic antenna is arranged outside the spin satellite platform and is fixedly connected to the upper surface of the spin satellite platform through a first folding and retracting structure. The dual-frequency precipitation radar main body is integrated inside the spin satellite platform. The radar antenna is fixedly connected to the side surface of the spin satellite platform through a second folding and retracting structure. The spin satellite platform spins at a preset spin period to drive the parabolic antenna and the radar antenna to perform a 360° wide-angle conical scan of the ground to complete ground observation. The comprehensive microwave detection imager adopts a multi-polarization, multi-frequency, and multi-channel design. All frequency bands covered by the comprehensive microwave detection imager form a feed array at the focal point corresponding to the parabolic antenna, so that all frequency bands covered by the comprehensive microwave detection imager share the same reflector. The dual-frequency precipitation radar main body includes a signal processing unit, a Ka / Ku up / down conversion unit, a Ka / Ku power amplification unit, a Ka / Ku waveguide network, and a slot antenna. Among them, the Ka / Ku up / down conversion unit up-converts the transmitted intermediate frequency signal generated by the signal processing unit based on the radar measurement and control instruction to a Ku transmitted radio frequency signal and a Ka transmitted radio frequency signal, and sends the output signal to the Ka / Ku power amplification unit for amplification processing. The Ka / Ku power amplification unit weights and combines the amplified signal through the Ka / Ku waveguide network and the slot antenna, and then radiates it outward through the radar antenna.

2. The active and passive microwave combined satellite spin-scanning detection system according to claim 1, wherein The microwave detection imaging main body includes a plurality of signal processing channels. The frequency bands covered by the plurality of signal processing channels include 6.8 GHz, 10.7 GHz, 18.7 GHz, 23.8 GHz, 31.4 GHz, 37 GHz, 50 - 60 GHz, 89 GHz, 118 GHz, 166 GHz, and 183 GHz. The comprehensive microwave detection imager supports a multi-polarization mode. The multi-polarization mode includes vertical polarization, horizontal polarization, and full polarization. The swath width covered by the comprehensive microwave detection imager is greater than or equal to 1500 kilometers.

3. The active and passive microwave combined satellite spin scan detection system according to claim 1, characterized in that, Different signal processing channels of the comprehensive microwave detection imager correspond to different application modes, and the corresponding channel configuration information between different signal processing channels is different. The channel configuration information at least includes the center frequency and the polarization mode.

4. The active and passive microwave combined satellite spin-scanning detection system according to claim 2, wherein The parabolic antenna adopts an offset feed design.

5. The active and passive microwave combined satellite spin scan detection system according to claim 4, wherein Among the multiple feeds corresponding to the feed array, the 6.8 GHz band and the 10.7 GHz band share one feed, the 18.7 GHz band, the 23.8 GHz band, the 31.4 GHz band and the 37 GHz band share one feed, the 50 - 60 GHz band shares one feed, the 89 GHz band and the 118 GHz band share one feed, and the 166 GHz band and the 183 GHz band share one feed. The microwave detection imaging main body includes a receiver module corresponding to each feed and a microwave numerical control unit, and the feed is connected to the microwave numerical control unit through the receiver module corresponding to the feed.

6. The active and passive microwave combined satellite spin scan detection system according to claim 5, wherein, The receiver module includes a receiver front end and a medium - low frequency receiver. Among them, when the active - passive microwave combined satellite spin - scan detection system is in the on - orbit working state: The parabolic antenna receives the microwave radiation signal corresponding to the observation target and transmits it to a plurality of receiver modules through the feed array. For each receiver module: The receiver front end down - converts the microwave radiation signal to an intermediate - frequency signal and performs pre - amplification processing, and transmits the processed signal to the medium - low frequency receiver. The medium - low frequency receiver sequentially performs signal amplification, square - law detection, low - frequency amplification and integration processing on the processed signal, and transmits the processed signal to the microwave numerical control unit. The microwave numerical control unit performs data analysis on the signals transmitted by each receiver module, determines the corresponding microwave observation result and sends it to the ground control center through the spin satellite platform.

7. The active - passive microwave combined satellite spin - scan detection system according to claim 1, wherein The Ka / Ku power amplification unit amplifies the Ku transmit radio - frequency signal and the Ka transmit radio - frequency signal respectively to obtain a Ku transmit power signal and a Ka transmit power signal. The Ka / Ku waveguide network and slot antenna perform weighted combination on the Ku transmit power signal and the Ka transmit power signal and radiate them outward through the radar antenna.

8. The active - passive microwave combined satellite spin - scan detection system according to claim 7, wherein The radar antenna receives the radar observation signal corresponding to the observation target and sends it to the Ka / Ku waveguide network and slot antenna. The Ka / Ku waveguide network and slot antenna perform power division on the radar observation signal to obtain a Ku receive radio - frequency signal and a Ka receive radio - frequency signal and send them to the Ka / Ku up - down conversion unit. The Ka / Ku up - down conversion unit down - converts the Ku receive radio - frequency signal to a Ku receive intermediate - frequency signal and down - converts the Ka receive radio - frequency signal to a Ka receive intermediate - frequency signal respectively. The signal processing unit collects the Ku receive intermediate - frequency signal and the Ka receive intermediate - frequency signal, and performs pulse compression processing on the Ku receive intermediate - frequency signal and the Ka receive intermediate - frequency signal to obtain precipitation echo scientific data in the Ku / Ka band and transmits it back to the ground control center through the spin satellite platform.

9. The active - passive microwave combined satellite spin - scan detection system according to claim 1, wherein When the paraboloid antenna is in the transmitting state of the active and passive microwave combined satellite spin-scanning detection system, it is in a retracted state through the first folding and retracting structure; When the paraboloid antenna is in the in-orbit working state of the active and passive microwave combined satellite spin-scanning detection system, it is in an unfolded state through the first folding and retracting structure.

10. The active and passive microwave combined satellite spin-scanning detection system according to claim 1, wherein When the radar antenna is in the transmitting state of the active and passive microwave combined satellite spin-scanning detection system, it is in a retracted state through the second folding and retracting structure; When the radar antenna is in the in-orbit working state of the active and passive microwave combined satellite spin-scanning detection system, it is in an unfolded state through the second folding and retracting structure.

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