Active and passive microwave combined satellite spin scanning detection system

Abstract

The embodiment of the invention provides an active and passive microwave combined satellite spin scanning detection system, and relates to the technical field of space microwave remote sensing. The parabolic antenna is arranged outside the spinning satellite platform and is fixedly connected with the upper surface of the spinning satellite platform through a first folding contraction structure; the dual-frequency precipitation radar main body is integrated in the spinning satellite platform, and the radar antenna is fixedly connected with the side surface of the spinning satellite platform through a second folding contraction structure; and the spinning satellite platform performs spinning according to a preset spinning period so as to drive the parabolic antenna and the radar antenna to perform 360-degree wide-width conical scanning to the earth to complete earth observation. The passive microwaves, the active radar and the satellite spinning platform are integrally designed, the passive microwaves and the active radar are driven by the rotation of the spinning satellite platform to perform 360-degree wide conical scanning on the ground, and the mass, the size, the power consumption and the cost of the whole satellite are greatly reduced while the observation precision is ensured.

Description

Technical Field

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

[0002] In the field of satellite remote sensing, the joint observation system of active radar and passive microwave radiometer has become an important means to improve monitoring accuracy. Among the typical foreign cases, the Global Precipitation Measurement Core (GPM) satellite (launched in 2014) led by NASA is the most representative. It is equipped with Ku / Ka dual-frequency precipitation radar and microwave imager. It obtains the vertical structure of precipitation through active radar and combines it with passive microwave wide-area observation to generate global high-precision precipitation products, which greatly improves the ability to predict extreme weather.

[0003] However, the existing joint observation system uses a microwave imager that 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, and forms an observation strip through cross-track phased array electronic scanning. In such a joint 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 joint observation system, but also increases the weight of the joint observation system, which increases the power consumption of the entire system and increases the observation cost. Summary of the invention

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

[0005] This application mainly includes the following aspects: In the first aspect, the embodiments of the present application provide The invention discloses an active-passive microwave combined satellite spin scanning detection system, which comprises a spinning satellite platform, an integrated microwave detection imager and a dual-frequency precipitation radar. The integrated microwave detection imager comprises a parabolic antenna and a microwave detection imaging body. The dual-frequency precipitation radar comprises a dual-frequency precipitation radar body and a radar antenna. The microwave detection imaging body is connected with the parabolic antenna, and the microwave detection imaging 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 contracting structure. The dual-frequency precipitation radar body is integrated inside the spinning satellite platform, and the radar antenna is fixedly connected to the side of the spinning satellite platform through a second folding and contracting structure. The spinning satellite platform spins with a preset spinning period to drive the parabolic antenna and the radar antenna to perform a 360-degree wide cone scanning of the ground to complete ground observation.

[0006] In a possible implementation, the integrated microwave detection imager adopts a multi-polarization, multi-frequency and multi-channel design, and the microwave detection imaging body includes multiple signal processing channels. The frequency bands covered by the multiple signal processing channels include 6.8GHz (gigahertz), 10.7GHz, 18.7GHz, 23.8GHz, 31.4GHz, 37GHz, 50~60GHz, 89GHz, 118GHz, 166GHz and 183GHz; the integrated microwave detection imager supports multi-polarization mode, and the multi-polarization mode includes vertical polarization, horizontal polarization and full polarization. The swath width covered by the integrated microwave detection imager is greater than or equal to 1500 kilometers.

[0007] In a possible implementation, different signal processing channels of the integrated microwave detection imager correspond to different application modes, and the channel configuration information corresponding to different signal processing channels is different, and the channel configuration information includes at least a center frequency and a polarization mode.

[0008] In a possible implementation, the parabolic antenna adopts an offset feed design, and all frequency bands covered by the integrated microwave detection imager form a feed source array at the focus corresponding to the parabolic antenna, so that all frequency bands covered by the integrated microwave detection imager share the same reflecting surface.

[0009] 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, and the 166 GHz band and the 183 GHz band share one feed, and the microwave detection imaging body includes a receiver module and a microwave numerical control unit corresponding to each feed, and the feed is connected to the microwave numerical control unit through the receiver module corresponding to the feed.

[0010] In a possible implementation, the receiver module includes a receiver front end and a medium and low frequency receiver, wherein, when the active and passive microwave joint satellite spin scanning detection system is in an orbital 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 and low frequency receiver, and the medium and low frequency receiver performs signal amplification, square-law detection, low-frequency amplification and integration processing on the processed signal in turn, 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 spinning satellite platform.

[0011] In a possible implementation, the dual-frequency precipitation radar 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, wherein the signal processing unit receives the radar measurement and control instructions corresponding to the spinning satellite platform, and generates the transmission intermediate frequency signal required for precipitation according to the radar measurement and control instructions, and sends the transmission intermediate frequency signal to the Ka / Ku up-down conversion unit; the Ka / Ku up-down conversion unit up-converts the transmission intermediate frequency signal to the Ku transmission radio frequency signal corresponding to the Ku band and the Ka transmission radio frequency signal corresponding to the Ka band; the Ka / Ku power amplification unit amplifies the Ku transmission radio frequency signal and the Ka transmission radio frequency signal respectively to obtain the Ku transmission power signal and the Ka transmission power signal; the Ka / Ku waveguide network and the slot antenna weightedly combine the Ku transmission power signal and the Ka transmission power signal, and radiate outward through the radar antenna.

[0012] In a possible implementation, a radar antenna receives a radar observation signal corresponding to an observation target and sends it to a Ka / Ku waveguide network and a slot antenna; the Ka / Ku waveguide network and the slot antenna perform power division on the radar observation signal to obtain a Ku receiving radio frequency signal and a Ka receiving radio frequency signal and send them to a Ka / Ku up / down conversion unit; the Ka / Ku up / down conversion unit down-converts the Ku receiving radio frequency signal into a Ku receiving intermediate frequency signal and down-converts the Ka receiving radio frequency signal into a Ka receiving intermediate frequency signal respectively; a signal processing unit collects the Ku receiving intermediate frequency signal and the Ka receiving intermediate frequency signal, and performs pulse compression processing on the Ku receiving intermediate frequency signal and the Ka receiving intermediate frequency signal to obtain scientific data of precipitation echoes in the Ku / Ka band and transmit them back to a ground control center via a spinning satellite platform.

[0013] In a possible implementation, when the active and passive microwave combined satellite spin scanning detection system is in a transmitting state, the parabolic antenna is in a folded state through a first folding and contracting structure; when the active and passive microwave combined satellite spin scanning detection system is in an orbital working state, the parabolic antenna is in an unfolded state through the first folding and contracting structure.

[0014] In a possible implementation, when the active and passive microwave combined satellite spin scanning detection system is in a transmitting state, the radar antenna is in a retracted state through a second folding and contracting structure; when the active and passive microwave combined satellite spin scanning detection system is in an orbital working state, the radar antenna is in an unfolded state through the second folding and contracting structure. An active-passive microwave combined satellite spin scanning detection system provided in an embodiment of the present application relates to the technical field of space microwave remote sensing. The microwave detection imaging body is connected to a parabolic antenna, which is arranged outside the spinning satellite platform and fixedly connected to the upper surface of the spinning satellite platform through a first folding and contracting structure; the dual-frequency precipitation radar body is integrated inside the spinning satellite platform, and the radar antenna is fixedly connected to the side of the spinning satellite platform through a second folding and contracting structure; the spinning satellite platform spins with a preset spin period to drive the parabolic antenna and the radar antenna to perform a 360° wide conical scan of the ground to complete ground observation. The present application integrates passive microwaves, active radars and satellite spinning platforms, and uses the rotation of the spinning satellite platform to drive passive microwaves and active radars to perform a 360° wide conical scan of the ground, which ensures the observation accuracy while greatly reducing the mass, volume, power consumption and cost of the entire satellite.

[0015] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, preferred embodiments are specifically cited below and described in detail with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0017] Figure 1 A schematic structural diagram of an active-passive microwave combined satellite spin scanning detection system provided in an embodiment of the present application is shown; Figure 2 The overall state configuration diagram of an active-passive microwave combined satellite spin scanning detection system provided by an embodiment of the present application when in a transmitting state is shown; Figure 3 The overall state configuration diagram of an active-passive microwave combined satellite spin scanning detection system provided by an embodiment of the present application when in an orbit-entering working state is shown; Figure 4 A schematic structural diagram of a comprehensive microwave detection imager provided in an embodiment of the present application is shown; Figure 5 A schematic structural diagram corresponding to a dual-frequency precipitation radar main body provided in an embodiment of the present application is shown; Figure 6 A schematic diagram of an observation strip of an active-passive microwave combined satellite spin scanning detection system provided in an embodiment of the present application is shown. DETAILED DESCRIPTION

[0018] To make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. It should be understood that the drawings in the present application only serve the purpose of explanation and description and are not used to limit the scope of protection of the present application. In addition, it should be understood that the schematic drawings are not drawn in real proportion. The flowchart used in this application shows the operations implemented according to some embodiments of the present application. It should be understood that the operations of the flowchart can be implemented out of sequence, and the steps without logical context can be reversed in order or implemented simultaneously. In addition, those skilled in the art, under the guidance of the content of the present application, can add one or more other operations to the flowchart, or remove one or more operations from the flowchart.

[0019] In addition, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various 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 application claimed for protection, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the present application.

[0020] Satellite remote sensing is the only means of observation that can monitor tropical storm processes. Using satellite remote sensing to monitor the formation, movement and evolution 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 the cloud and rain atmosphere, provide information inside the clouds, realize effective monitoring of large-scale typhoon structures and their changes, and monitor the entire process of typhoon occurrence, development and extinction in real time.

[0021] Atmospheric temperature, humidity, precipitation, air pressure and macro and micro parameters of clouds including cloud path, ice water content, particle size, etc. are important atmospheric physical parameters. They are of great significance for accurate weather forecasting, climate and water cycle, energy cycle and other earth science research. They are also key elements for achieving accurate and timely battlefield meteorological and marine environmental support.

[0022] Satellite-borne microwave radiometers are passive microwave remote sensors that detect objects 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 and stronger penetration capabilities, and can work all day and all weather, making them particularly suitable for observing geophysical parameters. They can not only be used in marine environment monitoring, atmospheric and meteorological observations, agricultural monitoring, geological exploration, and military reconnaissance, but also in terminal guidance of missiles, radio astronomy, and medical pathology research. Microwave radiometers can perform amplitude, phase, polarization, and coherence 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 size, light weight, and stable and reliable operation.

[0023] 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 blizzards. Its measurement parameters are independent of background radiation and directly related to precipitation. It can invert precipitation intensity more accurately than passive remote sensing, and can also obtain other rich precipitation information such as precipitation type and precipitation layer height. It can improve the space-based precipitation measurement capability, provide the three-dimensional structure of precipitation such as typhoons, heavy rains and blizzards, deepen the understanding of storm structure, cloud microphysics and mesoscale weather system dynamics, and improve the accuracy of meteorological forecasts such as precipitation.

[0024] In the field of satellite remote sensing, the joint observation system of active radar and passive microwave radiometer has become an important means to improve monitoring accuracy. Among the typical cases abroad, 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, which obtains the vertical structure of precipitation through active radar and combines it with passive microwave wide-area observation to generate global high-precision precipitation products, that is, calibrating the radiometer inversion algorithm through high-precision radar data, which greatly improves the extreme weather prediction ability.

[0025] However, the existing joint observation system uses a microwave imager that 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, and forms an observation strip through cross-track phased array electronic scanning. In such a joint 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 joint observation system, but also increases the weight of the joint observation system, which increases the power consumption of the entire system and increases the observation cost.

[0026] Based on this, the embodiment of the present application provides an active-passive microwave combined satellite spin scanning detection system, which integrates passive microwave and active radar with a satellite spin platform, and utilizes the rotation of the spin satellite platform to drive the passive microwave and active radar to perform a 360° wide cone scan of the ground, thereby ensuring the observation accuracy while greatly reducing the mass, volume, power consumption and cost of the entire satellite, as follows: See also Figure 1 , Figure 1 FIG. 1 is a schematic diagram showing the structure of an active-passive microwave combined satellite spin scanning detection system provided in an embodiment of the present application. Figure 1 As shown, the active-passive microwave combined satellite spin scanning detection system provided in the embodiment of the present application includes a payload 1 and a spinning satellite platform 2, the payload 1 includes a comprehensive microwave detection imager 11 and a dual-frequency precipitation radar 12, and the spinning satellite platform 2 includes a digital tube 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.

[0027] Among them, the integrated microwave detection imager 11 and the dual-frequency precipitation radar 12 exchange data with the digital control and data transmission subsystem 21 respectively.

[0028] See also Figure 2 , Figure 2 The figure shows the overall state configuration diagram of an active-passive microwave combined satellite spin scanning detection system provided by the embodiment of the present application when it is in the transmitting state. Figure 3 , Figure 3 FIG. 1 shows the overall state configuration diagram of an active-passive microwave combined satellite spin scanning detection system provided by an embodiment of the present application when it is in an orbital working state. Figure 2 and Figure 3 As shown, the integrated microwave detection imager 11 includes a parabolic antenna 110 and a microwave detection imaging body 111 , and the dual-frequency precipitation radar 12 includes a dual-frequency precipitation radar body (not shown in the figure) and a radar antenna 120 . The microwave detection imaging body 111 is connected to the parabolic antenna 110 (not shown in the figure), the microwave detection imaging body 111 is integrated inside the spinning satellite platform 2, and the parabolic antenna 110 is arranged outside the spinning satellite platform 2 and fixedly connected to the upper surface of the spinning satellite platform 2 through the first folding and contracting structure 3.

[0029] The main body of the dual-frequency precipitation radar is integrated inside the spinning satellite platform 2 , and the radar antenna 120 is connected to the main body of the dual-frequency precipitation radar. The radar antenna 120 is fixedly connected to the side of the spinning satellite platform 2 through the second folding and contracting structure 4 .

[0030] The spinning satellite platform 2 spins at a preset spinning period to drive the parabolic antenna 110 and the radar antenna 120 to perform a 360° wide conical scan of the ground to complete ground observation.

[0031] 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 of the spinning satellite platform 2 through their respective corresponding second folding and contracting structures 4, and the first radar antenna 1201 and the second radar antenna 1202 are arranged opposite to each other.

[0032] In a preferred embodiment, if Figure 2 As 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 folded state through the first folding and contracting structure 3, and the radar antenna 120 is in a folded state through the second folding and contracting structure 4.

[0033] like Figure 3As shown, when the active and passive microwave combined satellite spin scanning detection system is in the orbital working state, the parabolic antenna 110 is in an unfolded state through the first folding and contracting structure 3, and the radar antenna 120 is in an unfolded state through the second folding and contracting structure 4.

[0034] In a preferred embodiment, the active-passive microwave combined satellite spin scanning detection system provided by the present application realizes scanning observation of the payload through the whole-satellite rotation of the spinning satellite platform 2, and the corresponding preset spin period of the spinning satellite platform 2 can be set to 2~4 seconds / revolution.

[0035] In a specific embodiment, in the spinning satellite platform 2: For the energy and power distribution subsystem 23 , a body-mounted solar panel is arranged on the side of the spinning satellite platform 2 to obtain operating energy, so as to achieve power supply and distribution of the spinning satellite platform 2 and operating energy balance.

[0036] For the attitude and orbit control subsystem 25, the scanning orientation corresponding to the payload 1 is determined by the gyroscope and the optical auxiliary camera, the star map is taken every revolution by the gyroscope, momentum wheel, magnetic torquer, optical auxiliary camera, etc., the earth pointing is corrected in combination with the gyroscope data, satellite positioning is achieved by GPS, and attitude control is achieved by a magnetometer, etc.

[0037] The propulsion subsystem 24 is configured with electric propulsion or other propulsion devices to enable the spinning satellite platform 2 to spin at a preset spinning period.

[0038] The digital control and data transmission subsystem 21 is used to exchange data with the integrated microwave detection imager, dual-frequency precipitation radar and the ground control center.

[0039] In a preferred embodiment, the integrated microwave detection imager adopts a multi-polarization, multi-frequency and multi-channel design, and the microwave detection imaging body includes multiple signal processing channels. The frequency bands covered by the multiple signal processing channels include 6.8GHz (gigahertz), 10.7GHz, 18.7GHz, 23.8GHz, 31.4GHz, 37GHz, 50~60GHz (oxygen absorption band), 89GHz, 118GHz, 166GHz and 183GHz (water vapor absorption band).

[0040] The integrated microwave detection imager 11 supports multi-polarization modes, including vertical polarization, horizontal polarization and full polarization.

[0041] The integrated microwave detection imager 11 integrates the vertical detection of the atmosphere with the surface imaging function. The rotation of the spinning satellite platform 2 drives the parabolic antenna 110 corresponding to the integrated microwave detection imager 11 to perform continuous scanning of the entire field of view, so that the swath width covered by the integrated microwave detection imager 11 is greater than or equal to 1,500 kilometers.

[0042] In a preferred embodiment, different signal processing channels of the integrated microwave detection imager correspond to different application modes, and the channel configuration information corresponding to different signal processing channels is different, and the channel configuration information at least includes the center frequency and the polarization mode.

[0043] As shown in Tables 1 to 3, Tables 1 to 3 are the channel configuration and channel application tables of the comprehensive microwave detection imager.

[0044] Table 1

[0045] Table 2

[0046] Table 3

[0047] 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 of the corresponding signal processing channel is 6.8 GHz, the polarization mode is dual polarization, and the channel is applied to sea surface temperature observation.

[0048] In a preferred embodiment, the parabolic antenna 110 adopts an offset feed design, and all frequency bands covered by the integrated microwave detection imager 11 form a feed source array at the focus corresponding to the parabolic antenna 110, so that all frequency bands covered by the integrated microwave detection imager 11 share the same reflecting surface.

[0049] In another preferred embodiment, 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.

[0050] The microwave detection imaging body 111 includes a receiver module and a microwave digital control unit corresponding to each feed source, and the feed source is connected to the microwave digital control unit through the receiver module corresponding to the feed source.

[0051] See also Figure 4 , Figure 4 FIG. 1 shows a schematic diagram of the structure of a comprehensive microwave detection imager provided in an embodiment of the present application. Figure 4As shown, the integrated microwave detection imager provides a total of feed sources S1~S5, among which the 6.8 GHz band and the 10.7 GHz band share feed source S1, the 18.7 GHz band, the 23.8 GHz band, the 31.4 GHz band and the 37 GHz band share feed source S2, the 50~60 GHz band shares feed source S3, the 89 GHz band and the 118 GHz band share feed source S4, and the 166 GHz band and the 183 GHz band share feed source S5.

[0052] The microwave detection imaging body 111 includes a receiver module and a microwave digital control unit corresponding to each feed source. Each feed source is connected to the microwave digital control unit via the receiver module corresponding to the feed source. Preferably, the receiver module includes a receiver front end and a medium and low frequency receiver.

[0053] like Figure 4 As shown, the receiver module corresponding to the feed source S1 includes a receiver front end A1 and an intermediate frequency receiver B1 supporting 6.8 GHz / 10.7 GHz frequency bands, and the feed source S1 is connected to the microwave digital control unit through the receiver front end A1 and the intermediate frequency receiver B1.

[0054] The receiver module corresponding to the feed source S2 includes a receiver front end A2 and an intermediate frequency receiver B2 supporting 18.7 GHz / 23.8 GHz / 31.4 GHz / 37 GHz frequency bands. The feed source S2 is connected to the microwave digital control unit through the receiver front end A2 and the intermediate frequency receiver B1.

[0055] The receiver module corresponding to the feed source S3 includes a receiver front end A3 supporting the 50-60 GHz frequency band and a 15-channel intermediate frequency receiver B3. The feed source S3 is connected to the microwave digital control unit through the receiver front end A3 and the 15-channel intermediate frequency receiver B3.

[0056] The receiver module corresponding to the feed source S4 includes a receiver front end A4 and an 8-channel intermediate frequency receiver B4 supporting the 118 GHz frequency band, and a receiver front end A5 and an intermediate frequency receiver B5 supporting the 89 GHz frequency band. Among them, the feed source S3 is connected to the microwave digital control unit through the receiver front end A4 and the 8-channel intermediate frequency receiver B4 after passing through the duplexer, and is connected to the microwave digital control unit through the receiver front end A5 and the intermediate frequency receiver B5.

[0057] The receiver module corresponding to the feed source S5 includes a receiver front end A6 and a 5-channel intermediate frequency receiver B6 supporting the 183 GHz frequency band, and a receiver front end A7 and an intermediate frequency receiver B7 supporting the 166 GHz frequency band. The feed source S5 is connected to the microwave digital control unit through the receiver front end A6 and the 5-channel intermediate frequency receiver B4 after passing through the duplexer, and is connected to the microwave digital control unit through the receiver front end A7 and the intermediate frequency receiver B7.

[0058] Preferably, the microwave detection imaging body 111 also 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 implement feed port off-plane calibration using a normal temperature calibration black body and a cold space background temperature as reference sources. Specifically, the normal temperature calibration black body and the cosmic cold space background provide stable high temperature and low temperature reference sources for the comprehensive microwave detection imager, respectively.

[0059] In a preferred embodiment, when the active-passive microwave combined satellite spin scanning detection system is in the orbiting working state: 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 receivers. The intermediate and low frequency receivers perform signal amplification, square-law detection, low-frequency amplification and integration processing on the processed signal in turn, and transmit 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 spinning satellite platform.

[0060] Preferably, the microwave numerical control unit is used to digitize and process the received signal, and control the entire integrated microwave detection imager to work stably and orderly according to the processing result, and communicate with the spinning satellite platform through the CAN bus. Specifically, the specific functions of the microwave numerical control unit are as follows: 1) Collect and quantify the signals or data transmitted by each receiver module to obtain microwave observation results and adjust the channel gain inside each receiver module based on the microwave observation results to make the channels inside each receiver module work in the best state.

[0061] 2) Receive channel power-on and power-off remote sensing instructions sent by the ground control center or the spinning satellite platform to control the power-on and power-off operations of each channel in each receiver module.

[0062] 3) Receive the working status remote sensing instructions sent by the ground control center or the spinning satellite platform, and after decoding, control the working status of the entire integrated microwave detection imager according to the working status remote sensing instructions. 4) Encode and integrate the microwave observation results, and send them directly to the ground control center in the agreed data format or transmit them to the ground control center through a spinning satellite platform. After receiving the microwave observation results, the ground control center also parses them in the agreed data format.

[0063] In a preferred embodiment, see Figure 5 , Figure 5FIG. 1 shows a schematic diagram of the structure of a dual-frequency precipitation radar main body provided in an embodiment of the present application. Figure 5 As shown, the main body of the dual-frequency precipitation radar 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.

[0064] Among them, the power supply and distribution unit 1215 supplies power to the dual-frequency precipitation radar as a whole.

[0065] Preferably, the working process of the dual-frequency precipitation radar is divided into two processes: remote sensing command processing and observation signal processing. Figure 5 As shown in the figure, the remote sensing instruction processing process corresponding to the dual-frequency precipitation radar includes: The signal processing unit 1211 receives the radar measurement and control instructions corresponding to the spinning satellite platform 2, and generates the transmission intermediate frequency signal required for precipitation according to the radar measurement and control instructions, and sends the transmission intermediate frequency signal to the Ka / Ku up-down conversion unit 1212. The Ka / Ku up-down conversion unit 1212 up-converts the transmission intermediate frequency signal to the Ku transmission radio frequency signal corresponding to the Ku band and the Ka transmission radio frequency signal corresponding to the Ka band. The Ka / Ku power amplification unit 1213 amplifies the Ku transmission radio frequency signal and the Ka transmission radio frequency signal respectively to obtain the Ku transmission power signal and the Ka transmission power signal. The Ka / Ku waveguide network and slot antenna 1214 weightedly combine the Ku transmission power signal and the Ka transmission power signal, and radiate outward through the radar antenna.

[0066] like Figure 5 As shown in Figure 1, the observation signal processing process corresponding to the dual-frequency precipitation radar includes: The radar antenna 120 receives the radar observation signal corresponding to the observation target and sends it to the Ka / Ku waveguide network and the slot antenna 1214. The Ka / Ku waveguide network and the slot antenna 1214 perform power division on the radar observation signal to obtain the Ku receiving RF signal and the Ka receiving RF signal and send them to the Ka / Ku up / down conversion unit 1212. The Ka / Ku up / down conversion unit 1212 down-converts the Ku receiving RF signal to the Ku receiving intermediate frequency signal and down-converts the Ka receiving RF signal to the Ka receiving intermediate frequency signal respectively. The signal processing unit 1211 collects the Ku receiving intermediate frequency signal and the Ka receiving intermediate frequency signal, and performs pulse compression processing on the Ku receiving intermediate frequency signal and the Ka receiving intermediate frequency signal to obtain the precipitation echo scientific data in the Ku / Ka band and transmit it back to the ground control center through the spinning satellite platform 2.

[0067] Compared with the prior art, the present application is beneficial in that: 1) The active-passive microwave combined satellite spin scanning detection system provided in the present application, through the integrated design of payload and spin satellite platform, removes the rotating mechanism in the rotation mechanism of the traditional passive microwave radiometer and the phased array system formed by 128 transceiver units in the traditional precipitation radar, so as to achieve the best utilization rate of the resources of the whole satellite and greatly reduce the mass, volume and power consumption of the whole satellite. The active-passive microwave combined satellite spin scanning detection system provided in the present application is estimated to have a mass of less than 240kg (the mass of the same type of satellite provided by the existing technology requires several tons), and the power consumption is less than 300W, which greatly reduces the cost of satellite development and launch.

[0068] 2) The active-passive microwave combined satellite spin scanning detection system provided in this application completes a 360° wide conical scan of the ground by driving the integrated microwave detection imager (passive payload) and the dual-frequency precipitation radar (active payload) through the spin of the spinning satellite platform, which greatly expands the observation range of the active and passive payloads. Specifically, the observation range is expanded from the original partial strip to a complete circular strip, increasing the observation range and resampling area, thereby greatly improving the observation efficiency.

[0069] 3) The active-passive microwave combined satellite spin scanning detection system provided in this application eliminates the rotating mechanism carried in the traditional microwave detection imager, thus avoiding world-class technical difficulties such as the failure of the rotating mechanism and conductive slip ring in the active-passive microwave combined satellite spin scanning detection system on orbit. Compared with the current status, it can greatly extend the on-orbit service life of the entire satellite and improve the reliability of the entire active-passive microwave combined satellite spin scanning detection system.

[0070] 4) The satellite-borne precipitation radar provided by the prior art requires 128 transceiver units to form a phased array system, and an observation strip is formed by cross-track phased array electronic scanning. The phase scanning angle domain is only tens of degrees, and the observation strip is only 245km. Moreover, since the scanning system of the traditional satellite-borne precipitation radar is cross-track scanning, changes in the incident angle will cause observation errors. The dual-frequency precipitation radar in the active and passive microwave joint satellite spin scanning detection system provided in this application only needs to be simplified to one channel for each frequency point to transmit and receive, which greatly reduces the weight, power consumption and cost of the precipitation radar.

[0071] 5) Please refer to Figure 6 , Figure 6 FIG. 1 is a schematic diagram showing an observation strip of an active-passive microwave combined satellite spin scanning detection system provided in an embodiment of the present application. Figure 6As shown, the dual-frequency precipitation radar in the active-passive microwave joint satellite spin scanning detection system provided by the present application and the integrated microwave detection imager of the passive system are both conical scanning, and the incident angle is fixed, forming a complete circular strip on the ground, among which 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. It can be seen that the system provided by the present application greatly increases the scanning observation range, improves the observation efficiency, and is more conducive to improving the accuracy of active and passive joint observation inversion.

[0072] 6) The integrated microwave detection imager provided in this application includes all the classic channel configurations of traditional atmospheric sounders, dual-polarization microwave imagers and full-polarization microwave imagers, realizing the integrated design of imaging and detection. It also includes atmosphere, precipitation, sea surface and ocean dynamic environment, and land surface detection. Multi-channel and multi-factor simultaneous observation and joint inversion will greatly improve the observation accuracy, realize the integrated monitoring of ocean and atmospheric remote sensing, and expand the scope of application.

[0073] 7) The scanning system of traditional passive microwave detectors is a cross-orbit system, and changes in the incident angle will also cause data inversion errors. The active and passive microwave joint satellite spin scanning detection system provided in this application combines the detector and the imager to form a comprehensive microwave detection imager. The scanning system uses conical scanning, so that the incident angle remains unchanged, further improving the detection accuracy. At the same time, since the comprehensive microwave detection imager that integrates the detector and the imager uses a large-aperture parabolic antenna, the spatial resolution of the atmospheric vertical detection channel is greatly improved, which also further improves the observation performance of the comprehensive microwave detection imager.

[0074] 8) After the cost of the entire satellite is greatly reduced, multiple satellites can be networked to form an observation constellation, which will greatly improve the observation time and spatial resolution. It can realize high-frequency real-time detection of disastrous weather such as typhoons and river basin precipitation and their changing processes, fill the gap in active and passive microwave joint detection in high-frequency cloud and rain areas in the world, and greatly improve the disaster forecasting and warning capabilities including typhoon path and intensity forecasts.

[0075] 9) The active and passive microwave combined satellite spin scanning detection system provided in this application can realize 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 forecast and warning, sea surface wind speed and wind direction and other ocean dynamic environment detection, land surface vegetation index detection, etc., combined with active radar and passive microwave remote sensing, it can penetrate the cloud layer and realize all-weather and all-day precipitation monitoring, especially in extreme weather such as typhoons and heavy rains. It can widely serve meteorology, ocean, agriculture, transportation (low-altitude economy, civil aviation, shipping, etc.), finance, insurance, electricity and other industries, and has broad application prospects, important social value and huge commercial value.

[0076] Those skilled in the art can clearly understand that, for the convenience and simplicity of description, the specific working process of the system and device described above can refer to the corresponding process in the aforementioned method embodiment, and will not be repeated here. In the several embodiments provided in the present application, it should be understood that the disclosed system, device and method can be implemented in other ways. The device embodiments described above are merely schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation. For example, 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 mutual coupling or direct coupling or communication connection shown or discussed can be through some communication interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0077] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0078] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0079] If the function is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a non-volatile computer-readable storage medium that is executable by a processor. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art or the 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, including several instructions for a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM), random access memory (RAM), disk or optical disk, and other media that can store program codes.

[0080] The above are only specific implementations of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. An active-passive microwave combined satellite spin scanning detection system, characterized in that: The active-passive microwave combined satellite spin scanning detection system comprises a spin satellite platform, a comprehensive microwave detection imager and a dual-frequency precipitation radar, wherein the comprehensive microwave detection imager comprises a parabolic antenna and a microwave detection imaging body, and the dual-frequency precipitation radar comprises a dual-frequency precipitation radar body and a radar antenna. The microwave detection imaging body is connected to the parabolic antenna, the microwave detection imaging body is integrated inside the spinning satellite platform, and the parabolic antenna is arranged outside the spinning satellite platform and fixedly connected to the upper surface of the spinning satellite platform through a first folding and contracting structure; The dual-frequency precipitation radar body is integrated inside the spinning satellite platform, and the radar antenna is fixedly connected to the side of the spinning satellite platform through a second folding and contracting structure; The spinning satellite platform spins at a preset spinning period to drive the parabolic antenna and the radar antenna to perform a 360° wide conical scan of the ground to complete ground observation.

2. The active-passive microwave combined satellite spin scanning detection system according to claim 1 is characterized in that: The integrated microwave detection imager adopts multi-polarization, multi-frequency and multi-channel design. The microwave detection imaging body includes a plurality of signal processing channels, and 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 integrated microwave detection imager supports multi-polarization modes, which include vertical polarization, horizontal polarization and full polarization. The swath width covered by the integrated microwave detection imager is greater than or equal to 1500 kilometers.

3. The active-passive microwave combined satellite spin scanning detection system according to claim 1 is characterized in that: Different signal processing channels of the integrated microwave detection 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 a center frequency and a polarization mode.

4. The active-passive microwave combined satellite spin scanning detection system according to claim 2 is characterized in that: The parabolic antenna adopts an offset feed design, and all frequency bands covered by the integrated microwave detection imager form a feed source array at the focus corresponding to the parabolic antenna, so that all frequency bands covered by the integrated microwave detection imager share the same reflecting surface.

5. The active-passive microwave combined satellite spin scanning detection system according to claim 4 is characterized in that: 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 body comprises a receiver module corresponding to each feed source and a microwave digital control unit, and the feed source is connected to the microwave digital control unit through the receiver module corresponding to the feed source.

6. The active-passive microwave combined satellite spin scanning detection system according to claim 5 is characterized in that: The receiver module includes a receiver front end and a medium and low frequency receiver. Wherein, when the active-passive microwave combined satellite spin scanning detection system is in the orbiting working state: The parabolic antenna receives the microwave radiation signal corresponding to the observed 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, and the intermediate and low frequency receiver performs signal amplification, square law detection, low frequency amplification and integration processing on the processed signal in sequence, and transmits the processed signal to the microwave digital 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 spinning satellite platform.

7. The active-passive microwave combined satellite spin scanning detection system according to claim 1 is characterized in that: The dual-frequency precipitation radar body includes a signal processing unit, a Ka / Ku up / down frequency conversion unit, a Ka / Ku power amplification unit, a Ka / Ku waveguide network and a slot antenna. The signal processing unit receives the radar measurement and control instructions corresponding to the spinning satellite platform, generates the transmission intermediate frequency signal required for precipitation according to the radar measurement and control instructions, and sends the transmission intermediate frequency signal to the Ka / Ku up-down conversion unit; The Ka / Ku up / down conversion unit up-converts the transmit intermediate frequency signal to a Ku transmit radio frequency signal corresponding to the Ku band and a Ka transmit radio frequency signal corresponding to the Ka band respectively; The Ka / Ku power amplifier unit amplifies the Ku transmit radio frequency signal and the Ka transmit radio frequency signal to obtain a Ku transmit power signal and a Ka transmit power signal respectively; The Ka / Ku waveguide network and the slot antenna perform weighted combination on the Ku transmission power signal and the Ka transmission power signal, and radiate outwards through the radar antenna.

8. The active-passive microwave combined satellite spin scanning detection system according to claim 7 is characterized in that: 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 perform power division on the radar observation signal to obtain a Ku receiving radio frequency signal and a Ka receiving 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 received radio frequency signal into a Ku received intermediate frequency signal and down-converts the Ka received radio frequency signal into a Ka received intermediate frequency signal respectively; The signal processing unit collects the Ku receiving intermediate frequency signal and the Ka receiving intermediate frequency signal, and performs pulse compression processing on the Ku receiving intermediate frequency signal and the Ka receiving intermediate frequency signal to obtain precipitation echo scientific data in the Ku / Ka band and transmit the data back to the ground control center through the spinning satellite platform.

9. The active-passive microwave combined satellite spin scanning detection system according to claim 1 is characterized in that: When the active-passive microwave combined satellite spin scanning detection system is in a transmitting state, the parabolic antenna is in a folded state through a first folding and contracting structure; When the active-passive microwave combined satellite spin scanning detection system is in an orbit-entering working state, the parabolic antenna is in an unfolded state through the first folding and contracting structure.

10. The active-passive microwave combined satellite spin scanning detection system according to claim 1, characterized in that: When the active-passive microwave combined satellite spin scanning detection system is in a transmitting state, the radar antenna is in a folded state through the second folding and contracting structure; When the active-passive microwave combined satellite spin scanning detection system is in an orbit-entering working state, the radar antenna is in an unfolded state through the second folding and contracting structure.

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