WO2022171202A1 - 干涉成像高度计与激光雷达双星伴飞海洋观测方法及系统 - Google Patents

干涉成像高度计与激光雷达双星伴飞海洋观测方法及系统 Download PDF

Info

Publication number
WO2022171202A1
WO2022171202A1 PCT/CN2022/082975 CN2022082975W WO2022171202A1 WO 2022171202 A1 WO2022171202 A1 WO 2022171202A1 CN 2022082975 W CN2022082975 W CN 2022082975W WO 2022171202 A1 WO2022171202 A1 WO 2022171202A1
Authority
WO
WIPO (PCT)
Prior art keywords
ocean
satellite
observation
lidar
profile
Prior art date
Application number
PCT/CN2022/082975
Other languages
English (en)
French (fr)
Inventor
陈戈
唐军武
赵朝方
孙晗伟
陈卫标
刘杰
吴松华
马纯永
于方杰
王运华
刘秉义
田丰林
陈树果
杨杰
张本涛
Original Assignee
青岛海洋科学与技术国家实验室发展中心
中国海洋大学
北京无线电测量研究所
中国科学院上海光学精密机械研究所
中国空间技术研究院
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 青岛海洋科学与技术国家实验室发展中心, 中国海洋大学, 北京无线电测量研究所, 中国科学院上海光学精密机械研究所, 中国空间技术研究院 filed Critical 青岛海洋科学与技术国家实验室发展中心
Publication of WO2022171202A1 publication Critical patent/WO2022171202A1/zh

Links

Images

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S17/00—Systems using the reflection or reradiation of electromagnetic waves other than radio waves, e.g. lidar systems
    • G01S17/88—Lidar systems specially adapted for specific applications
    • G01S17/95—Lidar systems specially adapted for specific applications for meteorological use
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S17/00—Systems using the reflection or reradiation of electromagnetic waves other than radio waves, e.g. lidar systems
    • G01S17/88—Lidar systems specially adapted for specific applications
    • G01S17/89—Lidar systems specially adapted for specific applications for mapping or imaging
    • G01S17/90—Lidar systems specially adapted for specific applications for mapping or imaging using synthetic aperture techniques
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
    • G01S7/48—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S17/00
    • G01S7/4802—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S17/00 using analysis of echo signal for target characterisation; Target signature; Target cross-section
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
    • Y02A90/00—Technologies having an indirect contribution to adaptation to climate change
    • Y02A90/10—Information and communication technologies [ICT] supporting adaptation to climate change, e.g. for weather forecasting or climate simulation

Definitions

  • the present application relates to the technical field of ocean remote sensing satellite observation, and in particular, to a method and system for ocean observation with an interferometric imaging altimeter and a lidar double-star accompanying flight.
  • the embodiments of the present application provide an interferometric imaging altimeter and lidar dual-star-flying ocean observation method and system, so as to at least solve the problem of realizing wide-swath, sub-meso-scale ocean observation and near-ocean observation under the premise of low cost and low risk.
  • the problem of remote sensing detection of the thermocline is not limited.
  • the present application provides a method for observing the ocean with an interferometric imaging altimeter and a lidar double-star accompanying flight, including the following steps:
  • the observation step is used to observe ocean phenomena in the working orbit through the first satellite and the second satellite that accompany in the same working orbit, wherein the first satellite carries out the sea surface height observation by carrying an interferometric imaging altimeter, and the The second satellite conducts atmospheric and ocean profile observations by carrying ocean profile lidar;
  • the data transmission step is used to receive the atmospheric and oceanic profile observation data sent by the second satellite through the first satellite, and send it to the ground station together with the sea surface height observation data of the first satellite, and the ground station respectively.
  • the sea surface height observation data and the atmospheric and ocean profile observation data are processed to correspondingly obtain sea surface height observation results and atmospheric and ocean profile observation results.
  • the working orbit is a sun-synchronous orbit
  • the orbit height is 400-600 km.
  • the observation step includes a sea surface height observation step, transmitting electromagnetic waves through the interferometric imaging altimeter, receiving and collecting echo signals reflected by the sea surface after the electromagnetic waves are transmitted through the atmosphere, so as to obtain the sea surface Altitude observation data.
  • the interferometric imaging altimeter transmits the electromagnetic wave through a transmitting antenna, and receives the echo signal through a receiving antenna; wherein the receiving antenna is a digital multi-beam Phased Array Antenna.
  • the transmitting antenna is divided into two transmitting sub-arrays in the elevation direction, and the two transmitting sub-arrays are respectively located on the left and right sides of the sub-satellite point of the first satellite, so that the Simultaneous observation from both sides; there are two receiving antennas, and the two receiving antennas are respectively located at the ends of the left baseline and the right baseline of the first satellite.
  • the diameter of the receiving antenna is 2720 mm in azimuth ⁇ 112 mm in elevation, and the beam width is 0.1765 degrees ⁇ 4.287 degrees; the diameter of the transmitting antenna is 2720 mm in azimuth ⁇ 112 mm in elevation, and each of the The size of the transmitting sub-array is 2720mm in azimuth ⁇ 56mm in elevation, and the beam width is 0.1564 degrees ⁇ 7.6 degrees.
  • the sea surface height observation step further includes performing preliminary processing on the sea surface height observation data through onboard SAR real-time processing technology to reduce the amount of data per unit time.
  • the observation step further includes an atmospheric and ocean profile observation step, using the ocean profile lidar to emit dual-wavelength laser light, and using a composite detection technology of simulation and photon counting to detect and collect the dual-wavelength laser light The range-resolved echo signals on the atmospheric and oceanic transmission paths to obtain said atmospheric and oceanographic profile observations.
  • the step of observing the atmospheric and ocean profiles further includes adjusting the incident angle of the dual-wavelength laser light emitted by the ocean profile lidar to be 0° to 40° by swinging the second satellite. °.
  • the wavelengths of the dual-wavelength laser are 1064 nm and 532 nm
  • the laser repetition frequency of the dual-wavelength laser is 100 Hz
  • the receiving aperture of the ocean profile lidar is 1 m
  • the simulation is combined with photon counting
  • the time resolution of detection is 1 ns.
  • the 1064 nm sea surface echo is detected separately by wavelength spectroscopy, the 532 nm echo is separated by a high spectral resolution filter to separate meter scattering and molecular scattering, the molecular scattering is detected separately, and the meter scattering is positive Cross-polarization detection.
  • the observation step further includes adjusting the observation time interval of the first satellite and the second satellite.
  • the present application also provides an interferometric imaging altimeter and lidar dual-star companion flight ocean observation system, which applies the above-mentioned interferometric imaging altimeter and lidar dual-star companion flight ocean observation method, and the interferometric imaging altimeter and lidar dual-star companion flight ocean observation method
  • the observation system includes:
  • the first satellite obtains sea surface height observation data by carrying an interferometric imaging altimeter for sea surface height observation;
  • a second satellite which accompanies the first satellite in the same working orbit, and the second satellite obtains atmospheric and ocean profile observation data by carrying an ocean profile laser radar for atmospheric and ocean profile observation;
  • the first satellite also outputs the received ocean profile observation data output by the second satellite together with the sea surface height observation data to a ground station, and the ground station records the sea surface height observation data and
  • the atmospheric and ocean profile observation data are processed to obtain sea surface height observations and atmospheric and ocean profile observations.
  • the interferometric imaging altimeter and lidar dual-satellite accompanying flight ocean observation method and system adopts a new observation system of dual-star accompanying flight and synchronous observation, and the main payload of the first satellite is interferometric imaging.
  • the main payload of the second satellite is ocean profile lidar.
  • the above-mentioned interferometric imaging altimeter and lidar double-satellite accompanying flight ocean observation method and system adopts a new observation system of double-satellite accompanying flight and synchronous observation.
  • the near-simultaneous observation in the region can also realize the simultaneous observation in different spatial positions, which provides a flexible and efficient observation method for the study of oceanic phenomena of multiple temporal and spatial scales.
  • FIG. 1 is a schematic diagram of the accompanying flight of a first satellite and a second satellite in an interferometric imaging altimeter and a lidar dual-satellite accompanying ocean observation method provided by an embodiment of the present application;
  • FIG. 2 is a block diagram of a load structure of a first satellite provided by an embodiment of the present application
  • FIG. 3 is a structural block diagram of an ocean profile laser radar provided by an embodiment of the present application.
  • elevation direction refers to the direction perpendicular to the satellite speed; the azimuth or positional relationship indicated by the terms “left”, “right”, etc.
  • the positional relationship is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the indicated device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention.
  • the SAR specifically refers to Synthetic Aperture Radar (Synthetic Aperture Radar).
  • this embodiment provides an ocean observation method for an interferometric imaging altimeter and a lidar double-star accompanying flight, including the following steps:
  • Step S1 an observation step, used to observe ocean phenomena on the working orbit 3 through the first satellite 1 and the second satellite 2 accompanying the same working orbit 3, wherein the first satellite 1 carries out the sea surface height by carrying an interferometric imaging altimeter. Observation, the second satellite 2 conducts atmospheric and ocean profile observations by carrying ocean profile lidar;
  • Step S2 a data transmission step, used for receiving the atmospheric and oceanic profile observation data sent by the second satellite 2 through the first satellite 1, and sending it together with the sea surface height observation data of the first satellite 1 to the ground station, and the ground station
  • the height observation data and the atmospheric and ocean profile observation data are processed to obtain the corresponding sea surface height observation results and the atmospheric and ocean profile observation results.
  • the above-mentioned interferometric imaging altimeter and lidar dual-star accompanying flight ocean observation method adopts a new observation system of dual-star accompanying flight and synchronous observation.
  • the main payload of the first satellite 1 is the interferometric imaging altimeter
  • the main payload of the second satellite 2 is the ocean profile laser.
  • the sub-mesoscale ⁇ 10 km, that is, the resolution in the horizontal direction on the ocean can reach 10 km
  • the resolution of oceanic dynamic processes and the depth of the near thermocline ⁇ 100 m, that is, the distance in the vertical direction on the ocean can be determined). up to 100m) penetration, and the observation cost is low and the risk is low.
  • the above-mentioned interferometric imaging altimeter and lidar double-star accompanying flight ocean observation method adopts a new observation system of double-star accompanying flight and synchronous observation.
  • the near-simultaneous observation in the same area can also realize simultaneous observation in different spatial positions, which provides a flexible and efficient observation method for the study of oceanic phenomena on multiple temporal and spatial scales.
  • the "observation time interval” mentioned above refers to the time interval during which the first satellite 1 and the second satellite 2 observe the same ocean scene, and the time interval can be adjusted from seconds to minutes. The observed changes in ocean state during this time interval can be ignored and can therefore be considered “near-simultaneous".
  • the specific time interval adjustment method can be controlled by orbital phase adjustment, for example, realized by electronic propulsion or chemical propulsion device, which is a conventional operation in the field, and will not be described in detail here.
  • the ocean positions observed by the first satellite 1 and the second satellite 2 are slightly different in latitude and longitude, but the difference in the observed positions can be adjusted by adjusting the flight time between the first satellite 1 and the second satellite 2
  • the interval is controlled to realize the observation of the same area.
  • the specific adjustment method is a conventional operation in the field, and will not be repeated here.
  • This embodiment also provides an interferometric imaging altimeter and a lidar dual-satellite accompanying flight ocean observation system, applying the above-mentioned interferometric imaging altimeter and lidar dual-star accompanying flight ocean observation method, the interferometric imaging altimeter and lidar dual-star accompanying flight ocean observation system includes: :
  • the first satellite 1 obtains sea surface height observation data by carrying an interferometric imaging altimeter for sea surface height observation;
  • the second satellite 2 flies with the first satellite 1 in the same working orbit, and the second satellite 2 obtains atmospheric and ocean profile observation data by carrying an ocean profile laser radar for atmospheric and ocean profile observation;
  • the first satellite 1 also outputs the received ocean profile observation data output by the second satellite 2 together with the sea surface height observation data to the ground station, and the ground station processes the sea surface height observation data and the atmospheric and ocean profile observation data to obtain Sea level observations and atmospheric and ocean profile observations.
  • the orbits of the first satellite 1 and the second satellite 2 are designed as a working orbit 3 and a calibration orbit (not shown in the figure).
  • the working orbit refers to the orbit in which the satellite works when obtaining valid scientific data
  • the revisit period usually ranges from ten to twenty days
  • the calibration orbit refers to the performance debugging
  • the revisit period is designed to be one day, so as to improve the number of satellites passing through the calibration field and the test efficiency.
  • the orbital height of the working orbit 3 is 495.51 km
  • the orbit inclination angle is 97.3813°
  • the cycle period of the first satellite 1 and the second satellite 2 in the working orbit 3 is both 21 days
  • the number of laps per cycle is 21 days. Both are 320 laps.
  • the orbit height of the calibration orbit is 568.14km
  • the orbit inclination is 97.6843°.
  • the cycle period of the first satellite 1 and the second satellite 2 in the calibration orbit is 1 day, and the number of laps per cycle is 15.
  • Both the first satellite 1 and the second satellite 2 work in sun-synchronous orbits, with the same orbital parameters, and the local time of the descending node is designed to be nominally 1:30pm, so that after the first satellite 1 observes an area on the ocean, the The two satellites 2 can fly over the area after a certain time interval to complete the observation of the same area.
  • the remote sensors ie, the interferometric imaging altimeter and the ocean profile lidar
  • the remote sensors ie, the interferometric imaging altimeter and the ocean profile lidar
  • the observation time interval of the first satellite 1 and the second satellite 2 can be adjusted on-orbit, which can not only realize near-simultaneous observation in the same area, but also realize simultaneous observation in different spatial positions. Ocean phenomena at multiple spatial and temporal scales provide a flexible and efficient means of observation.
  • the first satellite 1 is equipped with an interferometric imaging altimeter to observe the sea surface height during the operation of the working orbit 3 .
  • the interferometric imaging altimeter transmits Ka-band electromagnetic waves through the transmitting antenna, and receives and collects the echo signals of the Ka-band electromagnetic waves transmitted by the atmosphere and reflected by the sea surface through the receiving antenna to obtain sea surface height observation data.
  • the receiving antenna is a digital multi-beam phased array antenna.
  • the main problem faced by the interferometric imaging altimeter is the contradiction between the observation swath and the measurement accuracy.
  • the larger the observation swath the lower the sea surface scattering ability, the lower the signal-to-noise ratio, and the lower the measurement accuracy.
  • the phased array digital beamforming receiving antenna forms multiple high-gain beams at the same time. By increasing the antenna gain, it compensates for the decrease of sea surface scattering and expands the observation angle, thereby obtaining a considerable signal-to-noise ratio and ensuring large-scale measurement accuracy.
  • the transmitting antenna is divided into two transmitting sub-arrays in the elevation direction, and the two transmitting sub-arrays are respectively located on the left and right sides of the sub-satellite point of the first satellite 1, so as to observe simultaneously on the left and right sides of the sub-satellite point;
  • There are two receiving antennas and the two receiving antennas are respectively located at the ends of the left baseline and the right baseline of the first satellite 1, which are perpendicular to the flight direction of the satellite.
  • the transmitting antenna is located on the body of the first satellite 1 to facilitate the deployment of the thermal control device, and the two receiving antennas are located at both ends of the baseline to facilitate maintaining the baseline. It should be noted that, in order to improve the isolation of the observation signals on the left and right sides of the sub-satellite point, waveform coding signals need to be used.
  • the first satellite 1 also has inter-satellite communication capabilities and communication capabilities with ground stations, and can receive the atmospheric and ocean profile observation data sent by the second satellite 2, and send it together with the sea surface height observation data generated by the interferometric imaging altimeter observation. to the ground station to complete the data transfer.
  • the interferometric imaging altimeter due to its wide swath and high resolution, will result in a high amount of data per unit time.
  • the higher data per unit time is required. It is difficult to complete the off-satellite transmission of the original echo signal, and the pressure of on-board storage is relatively large. Therefore, in this embodiment, the step of observing the sea surface height by the interferometric imaging altimeter further includes performing preliminary processing on the sea surface height observation data through the on-board SAR real-time processing technology to reduce the amount of data per unit time and achieve high-precision on-orbit processing.
  • FIG. 2 shows a block diagram of the payload structure of the first satellite 1 , and the payload of the first satellite 1 will be described in detail below with reference to FIG. 2 .
  • the main payload of the first satellite 1 is an interferometric imaging altimeter
  • the auxiliary payloads include a traditional sub-satellite point altimeter, a calibration radiometer, a baseline, etc.
  • the satellite platform provides the required power for the interferometric imaging altimeter, etc. Provide a suitable temperature environment to ensure that it works in the best working condition.
  • the double-sided swath of the interferometric imaging altimeter can reach 140km, the ocean signal resolution is 10km, and it has the technical characteristics of large swath and high precision, and has a certain international advanced nature. Subsystems and Electronic Equipment Subsystems.
  • the purpose of the antenna subsystem is to amplify the frequency synthesis excitation signal and radiate the microwave signal in the designated direction, receive the echo signal from the ground or the target, amplify the echo signal and send it to the receiver for processing.
  • the antenna subsystem includes two receiving antennas and one transmitting antenna, the two receiving antennas are located at the end of the baseline, and the transmitting antenna is located on the body of the first satellite 1 .
  • the diameter of the receiving antenna is 2720mm ⁇ 112mm (azimuth ⁇ elevation), and the beam width is 0.1765° ⁇ 4.287°.
  • the diameter of the transmitting antenna is designed to be 2720mm ⁇ 112mm (azimuth ⁇ elevation).
  • the transmitting antenna is divided into two sub-arrays in the elevation direction.
  • both the transmitting antenna and the receiving antenna are active phased arrays that scan one-dimensionally in the elevation direction, and have an electrically large size in the azimuth direction.
  • the electrically large size refers to the antenna size/wavelength>10.
  • the pitch direction unit spacing is small and the number of modules is large; the high-efficiency antenna sub-array with large electrical size in the azimuth direction is selected, and the number of modules is minimized to realize the lightweight and high gain of the antenna.
  • the antenna subsystem also includes a GaN millimeter-wave transmitting component, which consists of 8 transmitting module units. Both ends of the 8-channel transmitting module unit are connected to the transmitting antenna unit and the 8-channel feeding network respectively. The combined port of the feeding network is connected to the sub-array feeder. electrical network.
  • the antenna subsystem further includes Ka receiving components, which are mainly composed of limiter, low noise amplifier, image rejection filter, mixer, attenuator, power divider and control circuit.
  • Ka receiving components which are mainly composed of limiter, low noise amplifier, image rejection filter, mixer, attenuator, power divider and control circuit.
  • the main functions of the Ka receiving component include: receiving external control signals, setting the working state of the Ka receiving component according to the requirements of the upper-level system after the integration of the component control circuit; secondary voltage stabilization of the externally provided voltage; receiving external microwave signals, and converting the input microwave The signal is amplified with low noise, and the attenuation of the microwave signal is set as required; the received external microwave signal is output to the signal processor after twice frequency conversion.
  • the electronic equipment subsystem includes frequency integrated single machine, digital single machine, on-orbit processing single machine, power supply and distribution single machine, control single machine, etc.
  • the frequency integrated single machine is an important part of the load of the interferometric imaging altimeter. Its main functions include: generating a reference clock and sending it to the digital subsystem to generate AD sampling clock; generating Ka-band excitation signal (including digital waveform generation), amplifying and sending To the antenna subsystem; generate the local oscillator, the two local oscillators and the pilot correction signal required for the secondary frequency conversion of the Ka-band receiving component.
  • the on-orbit processing unit is responsible for imaging and processing the data output by the Ka receiving unit, and generating complex image data for output. It is also responsible for receiving the programs and parameters of telemetry and remote control distributed by the control unit and on-the-ground notes.
  • the Ka receiving components on both sides of the baseline are reconfigured.
  • the single control unit is integrated in the central electronic equipment of the interferometric imaging altimeter payload, which mainly completes the communication between the payload and the satellite platform computer, controls the payload work according to the platform command, monitors the collection, storage and some computing functions.
  • the main function of the control unit is to receive commands from the satellite platform, to complete the control of the working mode and working state of each sub-system of the interferometric imaging altimeter, to control the working sequence of each sub-system of the interferometric imaging altimeter, and to monitor the real-time monitoring of each sub-system of the interferometric imaging altimeter. Feedback the working status of the interferometric imaging altimeter system to the satellite platform.
  • the interferometric imaging altimeter carried by the first satellite 1 adopts the interferometric SAR (Synthetic Aperture Radar, synthetic aperture radar) system, and works in the case of a small angle of view.
  • the use of interferometric SAR improves the observation width and resolution of the interferometric imaging altimeter.
  • the main features of the payload of the first satellite 1 are: (1) The Ka-band is used; (2) The phased array digital beam-forming antenna system is used, and at the same time, the multi-beam increases the antenna gain and expands the observation angle; (3) The interference of two transmitters and two receivers is adopted. System, observe the left and right sides of the sub-satellite point at the same time.
  • the second satellite 2 is equipped with an ocean profile laser radar to perform atmospheric and ocean profile observations during the operation of the working orbit 3 .
  • the ocean profile lidar emits dual-wavelength lasers, and uses the composite detection technology of simulation and photon counting to detect and collect the distance-resolved echo signals of the dual-wavelength lasers on the transmission paths of the atmosphere and ocean to obtain atmospheric and oceanographic profile observation data.
  • the wavelengths of the dual-wavelength laser are 1064 nm and 532 nm
  • the laser repetition frequency of the dual-wavelength laser is 100 Hz
  • the receiving aperture of the ocean section lidar is 1 m
  • the time resolution of the composite detection of simulation and photon counting is 1ns.
  • the method further includes adjusting the incident angle of the dual-wavelength laser light emitted by the ocean profile lidar by swinging the second satellite 2 .
  • the incident angle is 0° ⁇ 40°.
  • the second satellite 2 is also capable of inter-satellite communication, which can send the atmospheric and oceanic profile observation data generated by the ocean profile lidar observation to the first satellite 1 to complete data transmission.
  • the main payload of the second satellite 2 is an ocean profile laser radar.
  • the laser radar uses blue-green wavelengths to obtain echo signals of the atmosphere, sea surface and ocean water bodies, uses near-infrared wavelengths to obtain sea surface echo signals, and uses elastic scattering signals. Obtain the ocean optical parameter profile, and use the polarization channel to obtain information such as the depolarization degree of suspended matter in the ocean.
  • the second satellite 2 provides the required power for the ocean profile lidar, and provides it with a suitable temperature environment to ensure that it works in the best working condition.
  • FIG. 3 shows a structural block diagram of the ocean profile lidar, and the ocean profile lidar will be described in detail below with reference to FIG. 3 .
  • the ocean profile lidar consists of five parts: laser emission source, receiving telescope, photoelectric detection unit, acquisition and processing unit and electric control box.
  • the laser emission light source adopts a relatively mature semiconductor laser pumped laser, and adopts frequency doubling (SHG) technology to achieve dual-wavelength narrow linewidth and high pulse energy laser output of 532nm and 1064nm.
  • the laser beam is emitted after the beam expander telescope compresses the divergence angle.
  • the beam expander telescope of the laser emitting light source is installed in the load compartment of the second satellite 2, and the optical axis points to the earth for observation, and forms a certain angle with the surface, so that the dual-wavelength laser forms a certain incident angle with the sea surface.
  • the ocean profile lidar needs to fine-tune the direction of the transmitting optical axis on-orbit to achieve the complete matching of the receiving and receiving optical axis of the radar.
  • the connection between the two wavelengths of the transmitting laser and the star sensor is established to measure the absolute pointing of the laser in real time.
  • the receiving telescope adopts a Cassegrain structure
  • the primary and secondary mirrors are made of lightweight silicon carbide (SiC) material
  • the primary mirror has a clear aperture of 1m to receive echo signals of two wavelengths.
  • the photoelectric detection unit adopts a combination of various detection mechanisms, and adopts linear detection technology with high bandwidth for 1064nm echo detection to ensure the accuracy of sea surface elevation detection.
  • the composite detection technology of simulation and photon counting is used to realize the detection of the echo detection of the seawater profile with a large dynamic range and the detection of the weak echo photon signals of the deep water with high sensitivity.
  • the 1064nm sea surface echo is detected separately by wavelength spectroscopy
  • the 532nm echo is separated from the m scattering and the molecular scattering by a high spectral resolution filter
  • the molecular scattering is detected separately
  • the m scattering is detected by orthogonal polarization.
  • a high spectral resolution filter is designed to realize high spectral resolution detection with a high rejection ratio, which can simultaneously separate the m scattering and molecular scattering of the atmosphere and the ocean, and improve the optical parameter profiles of the atmosphere and the ocean. Inversion accuracy.
  • high spectral resolution is conventionally understood in the art as spectral resolution up to the order of nanometers.
  • the photoelectric detection unit also includes a boresight monitoring system coupled on the receiving optical path.
  • a boresight monitoring system coupled on the receiving optical path.
  • the acquisition and processing unit is composed of a signal acquisition and preprocessing module, a system state monitoring module, a detector high-voltage module, a parameter calibration module and a general control module.
  • the signal acquisition and preprocessing module is used to realize the acquisition of the echo signals received by the four detection channels of the lidar, and also collect the laser emission waveform signals of two wavelengths. On the one hand, it is used for accurate distance calculation, and on the other hand It is used to monitor the working state of the laser.
  • the multi-channel high-precision data acquisition unit in the acquisition and processing unit performs synchronous full-waveform sampling on the multi-channel signals, and further performs preprocessing and data splicing. The data is packaged and stored and downloaded under the control of the master control module.
  • System status monitoring is used to collect system status monitoring information, and transmit it to the master control module for processing and downloading.
  • the parameter calibration module is used to calibrate the detector response, polarization ratio, laser energy, wavelength matching, etc.
  • the detector high voltage module is used to provide working voltage to the photodetectors of 4 detection channels.
  • the master control module is used to set parameters and monitor the status of each unit module of the ocean profile lidar, and realize the instruction and information interaction with the satellite platform.
  • the electric control box is composed of a secondary power supply, a laser drive source, a laser pointing control unit, a motor drive unit, and a temperature control unit.
  • the laser drive source generates a large amount of heat, which requires a heat pipe to conduct heat dissipation.
  • the entire electric control box realizes the laser drive, temperature control, system control and power distribution functions, and realizes power supply and communication with the satellite platform.
  • the data processing of the interferometric imaging altimeter includes on-orbit processing and ground processing.
  • the on-orbit processing includes digital beamforming, pulse compression processing, synthetic aperture processing, and interference preprocessing.
  • Ground processing includes interference processing, error extraction and correction, geographic projection and Code, and finally get the sea surface height observation result.
  • OBP Ka-band Radar Interferometer On-Board Processor
  • ATBD Jet Propulsion Laboratory Document
  • the data processing process of the ocean profile lidar is completed at the ground station, which is mainly to obtain the observation results of the optical parameter profile of the atmosphere and the ocean by inverting the echo signals at different distances.
  • the specific inversion method is well known in the art and will not be described in detail in this application. Reference may be made to Tackett, J.L., Winker, D.M., Getzewich, B.J., Vaughan, M.A., Young, S.A., and Kar, J., "CALIPSO lidar level 3 aerosol profile product:version 3 algorithm design”, Atmos.Meas.Tech., 11, 4129–4152, 2018.

Abstract

本申请涉及一种干涉成像高度计与激光雷达双星伴飞海洋观测方法及系统，其中，海洋观测方法包括：观测步骤，用于通过在同一工作轨道伴飞的第一卫星和第二卫星在工作轨道对海洋现象进行观测，其中，第一卫星通过搭载干涉成像高度计进行海面高度观测，第二卫星通过搭载海洋剖面激光雷达进行大气和海洋剖面观测；数据处理与传输步骤，用于通过第一卫星接收第二卫星发送的大气和海洋剖面观测数据，并与第一卫星的海面高度观测数据一起发送至地面站，地面站分别对海面高度观测数据以及大气和海洋剖面观测数据进行处理以获得观测结果。通过本申请，解决了在低成本、低风险的前提下，实现海洋宽刈幅、亚中尺度观测以及对海洋近温跃层的遥感探测的问题。

Description

干涉成像高度计与激光雷达双星伴飞海洋观测方法及系统
本申请要求在2021年04月02日提交中国专利局、申请号为202110361898.5、发明名称为“干涉成像高度计与激光雷达双星伴飞海洋观测方法及系统”的中国专利申请的优先权，其全部内容通过引用结合在本申请中。
技术领域
本申请涉及海洋遥感卫星观测技术领域，特别是涉及一种干涉成像高度计与激光雷达双星伴飞海洋观测方法及系统。
背景技术
目前，在人类海洋活动日益频繁、空间技术飞速发展、信息技术突飞猛进的全球背景下，海洋卫星领域正处于深刻变革的关键时期，卫星遥感技术的发展正逐步由关注载荷指标的先进性转向为追求解决科学问题的有效性。面向当前海洋科学迫切需求，世界海洋强国纷纷谋划发展以高分辨率动力成像和大功率垂直穿透载荷为代表的新一代海洋三维动力高分辨率遥感技术，以实现全海域、全天候、高时空分辨的三维遥感探测目标。
然而，海洋遥感采用的常规卫星载荷，在观测海面时不能进行宽刈幅观测，无法获取亚中尺度海洋现象的精细化动力过程，同时，只能观测到海面以下几十米的深度，不能实现海洋近温跃层时空结构的遥感探测。
因而，如何在低成本、低风险的前提下，实现对海洋的宽刈幅和亚中尺度观测，并实现对海洋近温跃层的遥感探测，是当前急需解决的一项技术问题。
发明内容
本申请实施例提供了一种干涉成像高度计与激光雷达双星伴飞海洋观测方法及系统，以至少解决在低成本、低风险的前提下，实现海洋宽刈幅、亚中尺度观测以及对海洋近温跃层的遥感探测的问题。
本申请一方面提供了一种干涉成像高度计与激光雷达双星伴飞海洋观测方法，包括如下步骤：
观测步骤，用于通过在同一工作轨道伴飞的第一卫星和第二卫星在所述工作轨道对海洋现象进行观测，其中，所述第一卫星通过搭载干涉成像高度计进行海面高度观测，所述第二卫星通过搭载海洋剖面激光雷达进行大气和海洋剖面观测；
数据传输步骤，用于通过所述第一卫星接收所述第二卫星发送的大气和海洋剖面观测数据，并与所述第一卫星的海面高度观测数据一起发送至地面站，所述地面站分别对所述海面高度观测数据以及所述大气和海洋剖面观测数据进行处理，对应得到海面高度观测结果以及大气和海洋剖面观测结果。
在其中一些实施例中，所述工作轨道为太阳同步轨道，轨道高度为400-600km。
在其中一些实施例中，所述观测步骤中包括海面高度观测步骤，通过所述干涉成像高度计发射电磁波，接收并采集所述电磁波经大气传输后被海面反射的回波信号，以获得所述海面高度观测数据。
在其中一些实施例中，在所述海面高度观测步骤中，所述干涉成像高度计通过发射天线发射所述电磁波，并通过接收天线接收所述回波信号；其中，所述接收天线为数字多波束相控阵天线。
在其中一些实施例中，所述发射天线俯仰向分为两个发射子阵，两个所述发射子阵分别位于所述第一卫星星下点的左右两侧，以在星下点左右两侧同时观测；所述接收天线为两个，两个所述接收天线分别位于所述第一卫星左基线和右基线的末端。
在其中一些实施例中，所述接收天线的口径为方位向2720mm×俯仰向112mm，波束宽度为0.1765度×4.287度；所述发射天线的口径为方位向2720mm×俯仰向112mm，每个所述发射子阵的尺寸为方位向2720mm×俯仰向56mm，波束宽度为0.1564度×7.6度。
在其中一些实施例中，所述海面高度观测步骤中，还包括通过星上SAR 实时处理技术对所述海面高度观测数据进行初步处理以降低单位时间内的数据量。
在其中一些实施例中，所述观测步骤中还包括大气和海洋剖面观测步骤，通过所述海洋剖面激光雷达发射双波长激光，并利用模拟与光子计数复合探测技术探测并采集所述双波长激光在大气和海洋传输路径上的距离分辨回波信号，以获得所述大气和海洋剖面观测数据。
在其中一些实施例中，所述大气和海洋剖面观测步骤中，还包括通过所述第二卫星的摆动，调整所述海洋剖面激光雷达发射的所述双波长激光的入射角为0°～40°。
在其中一些实施例中，所述双波长激光的波长为1064nm和532nm，所述双波长激光的激光重复频率为100Hz，所述海洋剖面激光雷达的接收口径为1m，所述模拟与光子计数复合探测的时间分辨率为1ns。
在其中一些实施例中，采用波长分光方式对1064nm海表回波单独探测，532nm回波经过高光谱分辨率滤波器分离米散射和分子散射，所述分子散射单独探测，所述米散射进行正交偏振探测。
在其中一些实施例中，所述观测步骤中，进一步还包括调整所述第一卫星和第二卫星的观测时间间隔。
本申请另一方面还提供了一种干涉成像高度计与激光雷达双星伴飞海洋观测系统，应用上述干涉成像高度计与激光雷达双星伴飞海洋观测方法，所述干涉成像高度计与激光雷达双星伴飞海洋观测系统包括：
第一卫星，通过搭载干涉成像高度计进行海面高度观测获得海面高度观测数据；
第二卫星，与所述第一卫星在同一工作轨道伴飞，所述第二卫星通过搭载海洋剖面激光雷达进行大气和海洋剖面观测获得大气和海洋剖面观测数据；
其中，所述第一卫星还将接收到的所述第二卫星输出的所述海洋剖面观测数据与所述海面高度观测数据一起输出至地面站，所述地面站对所述海面高度观测数据以及所述大气和海洋剖面观测数据进行处理，获得海面高度观 测结果以及大气和海洋剖面观测结果。
与现有技术相比，本申请实施例提供的干涉成像高度计与激光雷达双星伴飞海洋观测方法及系统，采取双星伴飞、同步观测的新型观测体制，其第一卫星的主载荷为干涉成像高度计，第二卫星的主载荷为海洋剖面激光雷达，通过二者的配合实现了亚中尺度(～10km)海洋动力过程的分辨和近温跃层深度(～100m)的穿透，且观测成本低、风险低。同时，上述干涉成像高度计与激光雷达双星伴飞海洋观测方法及系统，采取双星伴飞、同步观测的新型观测体制，通过控制第一卫星和第二卫星的观测时间和观测位置，既可实现同一区域的近同时观测，又可实现不同空间位置上同时观测，为研究多时空尺度的海洋现象提供了一种灵活、高效的观测手段。
本申请的一个或多个实施例的细节在以下附图和描述中提出，以使本申请的其他特征、目的和优点更加简明易懂。
附图说明
此处所说明的附图用来提供对本申请的进一步理解，构成本申请的一部分，本申请的示意性实施例及其说明用于解释本申请，并不构成对本申请的不当限定。在附图中：
图1是本申请实施例提供的干涉成像高度计与激光雷达双星伴飞海洋观测方法中第一卫星与第二卫星伴飞的示意图；
图2是本申请实施例提供的第一卫星的载荷结构框图；
图3是本申请实施例提供的海洋剖面激光雷达的结构框图；
上述附图中：1、第一卫星；2、第二卫星；3、工作轨道。
具体实施方式
为了使本申请的目的、技术方案及优点更加清楚明白，以下结合附图及实施例，对本申请进行描述和说明。应当理解，此处所描述的具体实施例仅仅用以解释本申请，并不用于限定本申请。基于本申请提供的实施例，本领域普通技术人员在没有作出创造性劳动的前提下所获得的所有其他实施例，都属于本申请保护的范围。
显而易见地，下面描述中的附图仅仅是本申请的一些示例或实施例，对于本领域的普通技术人员而言，在不付出创造性劳动的前提下，还可以根据这些附图将本申请应用于其他类似情景。此外，还可以理解的是，虽然这种开发过程中所作出的努力可能是复杂并且冗长的，然而对于与本申请公开的内容相关的本领域的普通技术人员而言，在本申请揭露的技术内容的基础上进行的一些设计，制造或者生产等变更只是常规的技术手段，不应当理解为本申请公开的内容不充分。
在本申请中提及“实施例”意味着，结合实施例描述的特定特征、结构或特性可以包含在本申请的至少一个实施例中。在说明书中的各个位置出现该短语并不一定均是指相同的实施例，也不是与其它实施例互斥的独立的或备选的实施例。本领域普通技术人员显式地和隐式地理解的是，本申请所描述的实施例在不冲突的情况下，可以与其它实施例相结合。
在本申请的描述中，需要理解的是，术语“俯仰向”是指垂直于卫星速度的方向；术语“左”、“右”等指示的方位或位置关系为基于附图所示的方位或位置关系，仅是为了便于描述本发明和简化描述，而不是指示或暗示所指的装置或元件必须具有特定的方位、以特定的方位构造和操作，因此不能理解为对本发明的限制。
除非另作定义，本申请所涉及的技术术语或者科学术语应当为本申请所属技术领域内具有一般技能的人士所理解的通常意义。本申请所涉及的“一”、“一个”、“一种”、“该”等类似词语并不表示数量限制，可表示单数或复数。本申请所涉及的术语“包括”、“包含”、“具有”以及它们任何变形，意图在于覆盖不排他的包含；例如包含了一系列步骤或元件的方法或产品没有限定于已列出的步骤或元件，而是可以还包括没有列出的步骤或元件，或可以还包括对于这些方法或产品固有的其它步骤或元件。本申请所涉及的术语“第一”、“第二”等仅仅是区别类似的对象，不代表针对对象的特定排序。
在本申请的描述中，所述SAR具体是指合成孔径雷达(Synthetic Aperture Radar)。
如图1所示，本实施例提供了一种干涉成像高度计与激光雷达双星伴飞海洋观测方法，包括如下步骤：
步骤S1：观测步骤，用于通过在同一工作轨道3伴飞的第一卫星1和第二卫星2在工作轨道3对海洋现象进行观测，其中，第一卫星1通过搭载干涉成像高度计进行海面高度观测，第二卫星2通过搭载海洋剖面激光雷达进行大气和海洋剖面观测；
步骤S2：数据传输步骤，用于通过第一卫星1接收第二卫星2发送的大气和海洋剖面观测数据，并与第一卫星1的海面高度观测数据一起发送至地面站，地面站分别对海面高度观测数据以及大气和海洋剖面观测数据进行处理，对应得到海面高度观测结果以及大气和海洋剖面观测结果。
上述干涉成像高度计与激光雷达双星伴飞海洋观测方法，采取双星伴飞、同步观测的新型观测体制，其第一卫星1的主载荷为干涉成像高度计，第二卫星2的主载荷为海洋剖面激光雷达，通过二者的配合实现了亚中尺度(～10km，即海洋上水平方向的分辨可达10km)海洋动力过程的分辨和近温跃层深度(～100m，即海洋上垂直方向的距离可达100m)的穿透，且观测成本低、风险低。同时，上述干涉成像高度计与激光雷达双星伴飞海洋观测方法，采取双星伴飞、同步观测的新型观测体制，通过控制第一卫星1和第二卫星2的观测时间间隔和观测位置，既可实现同一区域的近同时观测，又可实现不同空间位置上同时观测，为研究多时空尺度的海洋现象提供了一种灵活、高效的观测手段。
以上所述“观测时间间隔”是指第一卫星1和第二卫星2观测同一海洋场景的时间间隔，此时间间隔可调整至秒级至分钟级。在该时间间隔内被观测的海洋状态的变化可以被忽略，因此可以认为“近同时”。具体的时间间隔的调整方式可通过轨道相位调整进行控制，例如通过电子推进或化学推进装置实现，此为本领域的常规操作，本处不做赘述。
由于地球自转的存在，第一卫星1和第二卫星2先后观测的海洋位置在经纬度上略有差异，但该观测位置的差异可以通过调整第一卫星1和第二卫 星2之间的飞行时间间隔进行控制，实现同一区域的观测。具体调整方式为本领域的常规操作，本处不做赘述。
本实施例还提供了一种干涉成像高度计与激光雷达双星伴飞海洋观测系统，应用上述干涉成像高度计与激光雷达双星伴飞海洋观测方法，该干涉成像高度计与激光雷达双星伴飞海洋观测系统包括：
第一卫星1，通过搭载干涉成像高度计进行海面高度观测获得海面高度观测数据；
第二卫星2，与第一卫星1在同一工作轨道伴飞，第二卫星2通过搭载海洋剖面激光雷达进行大气和海洋剖面观测获得大气和海洋剖面观测数据；
其中，第一卫星1还将接收到的第二卫星2输出的海洋剖面观测数据与海面高度观测数据一起输出至地面站，地面站对海面高度观测数据以及大气和海洋剖面观测数据进行处理，获得海面高度观测结果以及大气和海洋剖面观测结果。
下面结合卫星轨道设计、第一卫星1和第二卫星2的功能设计，以及数据处理，对上述干涉成像高度计与激光雷达双星伴飞海洋观测方法及系统进行具体说明。
(一)卫星轨道设计
本实施例中，第一卫星1和第二卫星2的轨道设计为工作轨道3和定标轨道(图中未示出)两种。在本申请的描述中，工作轨道是指卫星获取有效科学数据时工作的轨道，通常重访周期在十几天至二十几天之间；定标轨道是指卫星入轨初期进行性能调试和测试的轨道，重访周期设计为1天，从而提高卫星通过定标场的次数和测试效率。其中，在本实施例中，工作轨道3的轨道高度为495.51km，轨道倾角为97.3813°，第一卫星1和第二卫星2在工作轨道3的循环周期均为21天，每周期运行圈数均为320圈。定标轨道的轨道高度为568.14km，轨道倾角为97.6843°，第一卫星1和第二卫星2在定标轨道的循环周期均为1天，每周期运行圈数均为15圈。第一卫星1和第二卫星2均工作于太阳同步轨道，具有相同的轨道参数，降交点地方时均 设计为标称1:30pm，使得第一卫星1对海洋上一个区域进行观测后，第二卫星2在一定时间间隔后可从该区域上空飞过，完成对同一区域的观测。在保持相对稳定的轨道相位关系条件下，可以确保第一卫星1和第二卫星2上的遥感器(即干涉成像高度计和海洋剖面激光雷达)对海洋同一区域进行联合观测。
需要说明的是，在观测步骤中，可在轨调整第一卫星1和第二卫星2的观测时间间隔，既可实现同一区域的近同时观测，又可实现不同空间位置上同时观测，为研究多时空尺度的海洋现象提供了一种灵活、高效的观测手段。
(二)第一卫星功能设计
本实施例中，第一卫星1通过搭载干涉成像高度计以在工作轨道3运行过程中进行海面高度观测。观测时，干涉成像高度计通过发射天线发射Ka波段电磁波，通过接收天线接收并采集Ka波段电磁波经大气传输后被海面反射的回波信号，以获得海面高度观测数据。
需要说明的是，本实施例中，接收天线为数字多波束相控阵天线。干涉成像高度计面临的主要问题是观测刈幅和测量精度之间的矛盾，观测刈幅越大，则海面散射能力降低，造成信噪比降低，导致测量精度下降，然而，本实施例中，采用相控阵数字波束形成接收天线，同时形成多个高增益波束，通过提高天线增益补偿海面散射的下降，扩大观测角度，进而获取可观的信噪比，保证大幅宽测量精度。
进一步的，本实施例中，发射天线俯仰向分为两个发射子阵，两个发射子阵分别位于第一卫星1星下点的左右两侧，以在星下点左右两侧同时观测；接收天线为两个，两个接收天线分别位于第一卫星1左基线和右基线的末端，与卫星飞行方向相垂直。本实施例中，发射天线位于第一卫星1本体有利于热控装置展开，两个接收天线分别位于基线两端有利于基线保持。需要说明的是，为了提高星下点左右两侧观测信号的隔离度，需采用波形编码信号。
此外，第一卫星1还具备星间通信能力和与地面站通信能力，可接收第二卫星2发送的大气和海洋剖面观测数据，并将其与干涉成像高度计观测产 生的海面高度观测数据一起发送至地面站，以完成数据传输。
需要说明的是，干涉成像高度计由于刈幅宽、分辨率高，会造成单位时间内的数据量较高，针对干涉成像高度计全时工作、见海开机的应用需求，单位时间内较高的数据量难以完成原始回波信号星地下传，且星上存储的压力较大。因而，本实施例中，干涉成像高度计进行海面高度观测步骤中，还包括通过星上SAR实时处理技术对海面高度观测数据进行初步处理以降低单位时间内的数据量，实现高精度在轨处理。需要说明的是，星上SAR实时处理技术为本领域的现有技术，可参见谢愚等发表的《星载SAR在轨实时成像处理技术研究》(计算机工程与应用,2016,52(S1),317-320)、北京理工大学刘小宁的博士论文《星上SAR实时成像处理关键技术研究》等，在此针对该技术不做具体详细说明。
图2示出了第一卫星1的载荷结构框图，下面结合图2对第一卫星1的载荷进行详细说明。
如图2所示，第一卫星1的主载荷为干涉成像高度计，辅载荷包括传统星下点高度计、校正辐射计、基线等，卫星平台为干涉成像高度计等提供所需的功率，并为其提供合适的温度环境，确保其工作在最佳工作状态。
下面针对主载荷干涉成像高度计进行详细说明：
本实施例中，干涉成像高度计的双侧刈幅可达140km，海洋信号分辨率为10km，具备大刈幅，高精度的技术特点，具有一定的国际先进性，主载荷干涉成像高度计具体包括天线子系统和电子设备子系统。
(1)天线子系统
天线子系统的用途是对频综激励信号进行放大后向指定方向辐射微波信号，接收地面或目标的回波信号，对回波信号进行放大并送至接收机进行处理。
天线子系统包括两个接收天线和一个发射天线，两个接收天线分置于基线的末端，发射天线位于第一卫星1本体。接收天线口径为2720mm×112mm(方位×俯仰)，波束宽度为0.1765度×4.287度。发射天线口径设计为 2720mm×112mm(方位×俯仰)，发射天线俯仰向分两个子阵，其中一个子阵向星下点左侧辐射，另一个子阵向星下点右侧辐射；每个子阵尺寸为2720mm×56mm(方位×俯仰)，波束宽度为0.1564度×7.6度。本实施例中，发射天线和接收天线均为俯仰向一维扫描的有源相控阵，方位向具有电大尺寸。其中，电大尺寸是指天线尺寸/波长＞10。为了保证发射天线和接收天线的俯仰向扫描范围，俯仰向单元间距小，模块数量多；选用方位向大电尺寸的高效天线子阵，尽量减少模块数量，以实现天线轻量化、高增益。
天线子系统还包括GaN毫米波发射组件，其由8个发射模块单元组成，8路发射模块单元两端分别与发射天线单元和8路馈电网络相连接，馈电网络合成端口接子阵馈电网络。
天线子系统进一步还包括Ka接收组件，主要由限幅器、低噪放、镜像抑制滤波器、混频器、衰减器、功分器和控制电路等组成。Ka接收组件主要功能包括：接收外部控制信号，经组件控制电路整合后按上级系统要求设定Ka接收组件工作状态；将外部提供的电压进行二次稳压；接收外部微波信号，将输入的微波信号进行低噪声放大，并按要求设置微波信号衰减量；将接收的外部微波信号，经过两次变频之后，输出给信号处理器。
(2)电子设备子系统
电子设备子系统包括频综单机、数字单机、在轨处理单机、供配电单机、控制单机等。
其中，频综单机是干涉成像高度计载荷的重要组成部分，主要功能包括：产生基准时钟送往数字子系统，用于产生AD采样时钟；产生Ka频段激励信号(包含数字波形产生)，放大后送往天线子系统；产生Ka波段接收组件二次变频所需的一本振、二本振和领示校正信号。
在轨处理单机负责对Ka接收组件输出的数据进行成像处理，并生成复图像数据进行输出，同时还负责接收控制单机分发的遥测遥控及地面上注的程序及参数，对在轨处理单机本身以及基线两侧的Ka接收组件进行重配置。
控制单机集成在干涉成像高度计载荷中央电子设备内，主要完成载荷与 卫星平台计算机之间的通信，根据平台命令控制载荷工作，监测量采集，存储和部分计算功能。控制单机的主要功能是接收卫星平台的命令，完成干涉成像高度计各分系统的工作模式与工作状态的控制，干涉成像高度计各分系统工作时序的控制、干涉成像高度计各分系统的实时监测，并向卫星平台反馈干涉成像高度计系统的工作状态。
总之，第一卫星1搭载的干涉成像高度计，采用干涉SAR(Synthetic Aperture Radar，合成孔径雷达)体制，工作于小视角情况，既利用了小视角情况下海面后向散射系数较强的优势，又利用干涉SAR提升了干涉成像高度计的观测幅宽和分辨率。第一卫星1的载荷主要特点有：(1)采用Ka频段；(2)采用相控阵数字波束形成天线体制，同时多波束提高天线增益扩大观测角度；(3)采用两发两收的干涉体制，在星下点左右两侧同时观测。
(三)第二卫星功能设计
本实施例中，第二卫星2通过搭载海洋剖面激光雷达以在在工作轨道3运行过程中进行大气和海洋剖面观测。观测时，海洋剖面激光雷达发射双波长激光，并利用模拟与光子计数复合探测技术探测并采集双波长激光在大气和海洋传输路径上的距离分辨回波信号，以获得大气和海洋剖面观测数据。需要说明的是，本实施例中，双波长激光的波长为1064nm和532nm，双波长激光的激光重复频率为100Hz，海洋剖面激光雷达的接收口径为1m，模拟与光子计数复合探测的时间分辨率为1ns。
进一步的，第二卫星2进行大气和海洋剖面观测步骤中，还包括通过第二卫星2的摆动，调整海洋剖面激光雷达发射的双波长激光的入射角。优选的，入射角为0°～40°。
此外，第二卫星2还具备星间通信能力，可将海洋剖面激光雷达观测产生的大气和海洋剖面观测数据发送至第一卫星1，以完成数据传输。
本实施例中，第二卫星2的主载荷为海洋剖面激光雷达，激光雷达利用蓝绿波长获取大气、海面和海洋水体回波信号，利用近红外波长获取海面回波信号，利用弹性散射信号，获取海洋光学参数剖面，辅助以偏振通道获取 海洋中悬浮物的退偏度等信息。第二卫星2为海洋剖面激光雷达提供所需的功率，并为其提供合适的温度环境，确保其工作在最佳工作状态。
图3示出了海洋剖面激光雷达的结构框图，下面结合图3对海洋剖面激光雷达进行详细说明。如图3所示，海洋剖面激光雷达由激光发射源、接收望远镜、光电探测单元、采集处理单元和电控箱等五部分组成。
(1)激光发射源
激光发射光源采用较成熟的半导体激光抽运的激光器，采用二倍频(SHG)技术实现532nm和1064nm的双波长窄线宽高脉冲能量激光输出，激光束经过扩束望远镜压缩发散角后发射。激光发射光源的扩束望远镜安装于第二卫星2的载荷舱，光轴指向地球进行观测，并与地表形成一定夹角，以使双波长激光与海面构成一定的入射角。海洋剖面激光雷达须在轨对发射光轴指向进行微调节，实现雷达收发光轴完全匹配，同时建立两个波长发射激光与星敏感器的联系，用于实时测量激光的绝对指向。
(2)接收望远镜
接收望远镜采用卡赛格林式结构，主次镜采用轻量化设计的碳化硅(SiC)材质，主镜通光口径1m，接收两个波长的回波信号。
(3)光电探测单元
光电探测单元采用多种探测机制相结合的方式，对于1064nm回波探测采用具有高带宽的线性探测技术，确保海表高程探测的精度。对于大气和海水散射的532nm回波信号探测则采用模拟和光子计数的复合探测技术，在实现大动态范围海水剖面回波探测的同时，实现高灵敏度的深水微弱回波光子信号的探测。具体的，采用波长分光方式对1064nm海表回波单独探测，532nm回波经过高光谱分辨率滤波器分离米散射和分子散射，分子散射单独探测，米散射进行正交偏振探测。本实施例采用的光电探测单元中，设计高光谱分辨率滤波器，实现高抑制比的高光谱分辨率探测，可同时分离大气和海洋的米散射和分子散射，提升大气和海洋的光学参数剖面反演精度。其中，高光谱分辨率根据本领域常规理解为高达纳米数量级的光谱分辨率。
同时，光电探测单元还包括耦合在接收光路上的视轴监视系统，通过对发射激光在视轴监视系统中CCD像面上的位置，监视激光发射光轴和接收望远镜光轴的偏移，反馈给激光发射光轴指向调节机构。
(4)采集处理单元
采集处理单元由信号采集和预处理模块、系统状态监测模块、探测器高压模块、参数定标模块和总控模块组成。
其中，信号采集和预处理模块用于实现激光雷达4个探测通道接收的回波信号的采集，同时还采集两个波长的激光发射波形信号，一方面用于精确的距离解算，另一方面则用于对激光器工作状态的监控。采集处理单元中多路高精度数据采集单元对多路信号进行同步的全波形采样，进一步进行预处理和数据拼接，数据打包后存储并在总控模块的控制下进行下传。
系统状态监测用于采集系统状态监测信息采集，并传输至总控模块进行处理下传。
参数定标模块用于对探测器响应、偏振比、激光能量、波长匹配等进行定标。
探测器高压模块用于向4个探测通道的光电探测器提供工作电压。
总控模块用于对海洋剖面激光雷达的各单元模块进行参数设置和状态监测，并实现与卫星平台的指令和信息交互。
(5)电控箱
电控箱由二次电源、激光驱动源、发射激光指向控制单元、电机驱动单元和温控单元等组成。其中，激光驱动源发热量较大，需要热管传导散热。整个电控箱实现激光器的驱动、温控、系统控制和配电功能，实现和卫星平台的供电和通信。
(四)数据处理
干涉成像高度计的数据处理包括在轨处理和地面处理，其中，在轨处理包括数字波束形成、脉冲压缩处理、合成孔径处理、干涉预处理，地面处理包括干涉处理、误差提取与修正、地理投影和编码，最终得到海面高度观测 结果。以上所述各数据处理方法为本领域公知，本申请不做详细描述，具体可参考Eva Peral,“KaRIn:Ka-band Radar Interferometer On-Board Processor(OBP)Algorithm Theoretical Basis Document(ATBD)”,Jet Propulsion Laboratory Document:D-79130,Aug.03,2021。
海洋剖面激光雷达的数据处理过程都在地面站完成，其主要为通过对不同距离的回波信号进行反演，以获得大气和海洋的光学参数剖面观测结果。具体反演方法为本领域公知，本申请不做详细描述，可参考Tackett,J.L.,Winker,D.M.,Getzewich,B.J.,Vaughan,M.A.,Young,S.A.,and Kar,J.,“CALIPSO lidar level 3 aerosol profile product:version 3 algorithm design”,Atmos.Meas.Tech.,11,4129–4152,2018.
以上实施例的各技术特征可以进行任意的组合，为使描述简洁，未对上述实施例中的各个技术特征所有可能的组合都进行描述，然而，只要这些技术特征的组合不存在矛盾，都应当认为是本说明书记载的范围。
以上实施例仅表达了本申请的几种实施方式，其描述较为具体和详细，但并不能因此而理解为对发明专利范围的限制。应当指出的是，对于本领域的普通技术人员来说，在不脱离本申请构思的前提下，还可以做出若干变形和改进，这些都属于本申请的保护范围。因此，本申请专利的保护范围应以所附权利要求为准。

Claims (13)

  1. 一种干涉成像高度计与激光雷达双星伴飞海洋观测方法，其特征在于，包括如下步骤：
    观测步骤，用于通过在同一工作轨道伴飞的第一卫星和第二卫星在所述工作轨道对海洋现象进行观测，其中，所述第一卫星通过搭载干涉成像高度计进行海面高度观测，所述第二卫星通过搭载海洋剖面激光雷达进行大气和海洋剖面观测；
    数据传输步骤，用于通过所述第一卫星接收所述第二卫星发送的大气和海洋剖面观测数据，并与所述第一卫星的海面高度观测数据一起发送至地面站，所述地面站分别对所述海面高度观测数据以及所述大气和海洋剖面观测数据进行处理，对应得到海面高度观测结果以及大气和海洋剖面观测结果。
  2. 根据权利要求1所述的干涉成像高度计与激光雷达双星伴飞海洋观测方法，其特征在于，所述工作轨道为太阳同步轨道，轨道高度为400-600km。
  3. 根据权利要求1所述的干涉成像高度计与激光雷达双星伴飞海洋观测方法，其特征在于，所述观测步骤中包括：
    海面高度观测步骤：通过所述干涉成像高度计发射电磁波，接收并采集所述电磁波经大气传输后被海面反射的回波信号，以获得所述海面高度观测数据。
  4. 根据权利要求3所述的干涉成像高度计与激光雷达双星伴飞海洋观测方法，其特征在于，在所述海面高度观测步骤中，所述干涉成像高度计通过发射天线发射所述电磁波，并通过接收天线接收所述回波信号；其中，所述接收天线为数字多波束相控阵天线。
  5. 根据权利要求4所述的干涉成像高度计与激光雷达双星伴飞海洋观测方法，其特征在于，所述发射天线俯仰向分为两个发射子阵，两个所述发射子阵分别位于所述第一卫星星下点的左右两侧，以在星下点左右两侧同时观测；所述接收天线为两个，两个所述接收天线分别位于所述第一卫星左基线和右基线的末端。
  6. 根据权利要求5所述的干涉成像高度计与激光雷达双星伴飞海洋观测方法，其特征在于，所述接收天线的口径为方位向2720mm×俯仰向112mm，波束宽度为0.1765度×4.287度；所述发射天线的口径为方位向2720mm×俯仰向112mm，每个所述发射子阵的尺寸为方位向2720mm×俯仰向56mm，波束宽度为0.1564度×7.6度。
  7. 根据权利要求3所述的干涉成像高度计与激光雷达双星伴飞海洋观测方法，其特征在于，所述海面高度观测步骤中，还包括通过星上SAR实时处理技术对所述海面高度观测数据进行初步处理以降低单位时间内的数据量。
  8. 根据权利要求1所述的干涉成像高度计与激光雷达双星伴飞海洋观测方法，其特征在于，所述观测步骤中还包括：
    大气和海洋剖面观测步骤：通过所述海洋剖面激光雷达发射双波长激光，并利用模拟与光子计数复合探测技术探测并采集所述双波长激光在大气和海洋传输路径上的距离分辨回波信号，以获得所述大气和海洋剖面观测数据。
  9. 根据权利要求8所述的干涉成像高度计与激光雷达双星伴飞海洋观测方法，其特征在于，所述大气和海洋剖面观测步骤中，还包括通过所述第二卫星的摆动，调整所述海洋剖面激光雷达发射的所述双波长激光的入射角为0°～40°。
  10. 根据权利要求8所述的干涉成像高度计与激光雷达双星伴飞海洋观测方法，其特征在于，所述双波长激光的波长为1064nm和532nm，所述双波长激光的激光重复频率为100Hz，所述海洋剖面激光雷达的接收口径为1m，所述模拟与光子计数复合探测的时间分辨率为1ns。
  11. 根据权利要求10所述的干涉成像高度计与激光雷达双星伴飞海洋观测方法，其特征在于，采用波长分光方式对1064nm海表回波单独探测，532nm回波经过高光谱分辨率滤波器分离米散射和分子散射，所述分子散射单独探测，所述米散射进行正交偏振探测。
  12. 根据权利要求1所述的干涉成像高度计与激光雷达双星伴飞海洋观测方法，其特征在于，所述观测步骤中，进一步还包括调整所述第一卫星和 第二卫星的观测时间间隔。
  13. 一种干涉成像高度计与激光雷达双星伴飞海洋观测系统，其特征在于，应用上述权利要求1-12任一项所述的干涉成像高度计与激光雷达双星伴飞海洋观测方法，所述干涉成像高度计与激光雷达双星伴飞海洋观测系统包括：
    第一卫星，通过搭载干涉成像高度计进行海面高度观测获得海面高度观测数据；
    第二卫星，与所述第一卫星在同一工作轨道伴飞，所述第二卫星通过搭载海洋剖面激光雷达进行大气和海洋剖面观测获得大气和海洋剖面观测数据；
    其中，所述第一卫星还将接收到的所述第二卫星输出的所述海洋剖面观测数据与所述海面高度观测数据一起输出至地面站，所述地面站对所述海面高度观测数据以及所述大气和海洋剖面观测数据进行处理，获得海面高度观测结果以及大气和海洋剖面观测结果。
PCT/CN2022/082975 2021-04-02 2022-03-25 干涉成像高度计与激光雷达双星伴飞海洋观测方法及系统 WO2022171202A1 (zh)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN202110361898.5A CN113126122B (zh) 2021-04-02 2021-04-02 干涉成像高度计与激光雷达双星伴飞海洋观测方法及系统
CN202110361898.5 2021-04-02

Publications (1)

Publication Number Publication Date
WO2022171202A1 true WO2022171202A1 (zh) 2022-08-18

Family

ID=76774724

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2022/082975 WO2022171202A1 (zh) 2021-04-02 2022-03-25 干涉成像高度计与激光雷达双星伴飞海洋观测方法及系统

Country Status (2)

Country Link
CN (1) CN113126122B (zh)
WO (1) WO2022171202A1 (zh)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115392136A (zh) * 2022-10-27 2022-11-25 中国石油大学(华东) 多模式一体化微波遥感器的信号时序优化模型
CN115453559A (zh) * 2022-09-20 2022-12-09 中国科学技术大学 一种基于动态数据进行多激光雷达时空同步的方法
CN115629364A (zh) * 2022-12-22 2023-01-20 中国海洋大学 一种面向动态海面的星载小角度sar海况偏差仿真方法
CN116165660A (zh) * 2023-04-20 2023-05-26 西安空间无线电技术研究所 多频段海洋环境航空综合探测系统
CN116859344A (zh) * 2023-08-28 2023-10-10 中国电子科技集团公司第十四研究所 一种面向相干最优的能谱自适应分布式InSAR空间同步方法

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113126122B (zh) * 2021-04-02 2023-03-28 青岛海洋科学与技术国家实验室发展中心 干涉成像高度计与激光雷达双星伴飞海洋观测方法及系统
CN113671504A (zh) * 2021-08-26 2021-11-19 中国空间技术研究院 分布式双星成像高度计抗回波干扰差频设计方法
CN113541774B (zh) * 2021-09-17 2021-12-24 椭圆时空(北京)科技有限公司 一种通遥一体化卫星系统
CN114114253A (zh) * 2021-11-30 2022-03-01 南京微麦科斯电子科技有限责任公司 一种基于人工智能算法的海浪监测阵列雷达
CN114252875B (zh) * 2021-12-24 2024-04-26 中国人民解放军海军潜艇学院 一种成像高度计数据的高精度网格化方法
CN114518577B (zh) * 2022-02-09 2023-02-07 北京卫星信息工程研究所 星载sar与gnss-s一体化系统及协同探测方法

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6864828B1 (en) * 2003-02-18 2005-03-08 Lockheed Martin Corporation Method and apparatus for collection and processing of interferometric synthetic aperture radar data
CN106352858A (zh) * 2016-11-21 2017-01-25 中国科学院大气物理研究所 一种大气海洋观测平台、系统、方法
CN108540775A (zh) * 2018-04-24 2018-09-14 宁波世纪海洋信息科技有限公司 一种船载多元海洋信息采集系统
CN113126122A (zh) * 2021-04-02 2021-07-16 青岛海洋科学与技术国家实验室发展中心 干涉成像高度计与激光雷达双星伴飞海洋观测方法及系统

Family Cites Families (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2886022B1 (fr) * 2005-05-18 2007-06-22 Agence Spatiale Europeenne Procede pour l'etablissement d'images cartographiques de vecteurs de vitesses de courants marins de surface et systeme de radar altimetrique mettant en oeuvre le procede
CN115336420B (zh) * 2013-08-30 2016-11-30 上海无线电设备研究所 底视合成孔径与近底视双刈幅干涉成像的一体化探测装置
FR3017213B1 (fr) * 2014-01-31 2016-02-05 Thales Sa Procede et systeme radiofrequence de determination, par couple d'engins spatiaux, de la position angulaire relative entre plusieurs engins spatiaux distants
FR3062484B1 (fr) * 2017-01-30 2020-10-09 Extreme Wheather Expertises Exwexs Procede et dispositif de meteorologie et produit programme d'ordinateur associe
CN108008380B (zh) * 2017-11-29 2020-03-31 中国科学技术大学 一种基于卫星编队的微波凝视关联成像方法及系统
CN109240322B (zh) * 2018-09-30 2020-11-24 南京航空航天大学 一种面向对地超幅宽成像的卫星编队实现方法
CN110501734B (zh) * 2019-08-14 2021-08-06 上海卫星工程研究所 双星编队sar卫星联合测试系统及方法
CN111913179B (zh) * 2020-08-20 2023-04-11 上海无线电设备研究所 一种提高星载雷达高度计近海岸观测能力的方法
CN112558106B (zh) * 2020-11-12 2022-06-07 北京遥测技术研究所 一种星载大气海洋高重频激光雷达系统及探测方法
CN112526482B (zh) * 2020-11-30 2024-04-09 北京遥测技术研究所 一种星载激光近海岸地形探测激光雷达及探测方法

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6864828B1 (en) * 2003-02-18 2005-03-08 Lockheed Martin Corporation Method and apparatus for collection and processing of interferometric synthetic aperture radar data
CN106352858A (zh) * 2016-11-21 2017-01-25 中国科学院大气物理研究所 一种大气海洋观测平台、系统、方法
CN108540775A (zh) * 2018-04-24 2018-09-14 宁波世纪海洋信息科技有限公司 一种船载多元海洋信息采集系统
CN113126122A (zh) * 2021-04-02 2021-07-16 青岛海洋科学与技术国家实验室发展中心 干涉成像高度计与激光雷达双星伴飞海洋观测方法及系统

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115453559A (zh) * 2022-09-20 2022-12-09 中国科学技术大学 一种基于动态数据进行多激光雷达时空同步的方法
CN115392136A (zh) * 2022-10-27 2022-11-25 中国石油大学(华东) 多模式一体化微波遥感器的信号时序优化模型
CN115629364A (zh) * 2022-12-22 2023-01-20 中国海洋大学 一种面向动态海面的星载小角度sar海况偏差仿真方法
CN116165660A (zh) * 2023-04-20 2023-05-26 西安空间无线电技术研究所 多频段海洋环境航空综合探测系统
CN116165660B (zh) * 2023-04-20 2023-07-18 西安空间无线电技术研究所 多频段海洋环境航空综合探测系统
CN116859344A (zh) * 2023-08-28 2023-10-10 中国电子科技集团公司第十四研究所 一种面向相干最优的能谱自适应分布式InSAR空间同步方法
CN116859344B (zh) * 2023-08-28 2023-11-03 中国电子科技集团公司第十四研究所 一种面向相干最优的能谱自适应分布式InSAR空间同步方法

Also Published As

Publication number Publication date
CN113126122B (zh) 2023-03-28
CN113126122A (zh) 2021-07-16

Similar Documents

Publication Publication Date Title
WO2022171202A1 (zh) 干涉成像高度计与激光雷达双星伴飞海洋观测方法及系统
US20220194582A1 (en) High Altitude, Long Endurance, Unmanned Aircraft and Methods of Operation Thereof
Nemoto et al. Japanese earth resources satellite-1 synthetic aperture radar
Rosen et al. An update on the NASA-ISRO dual-frequency DBF SAR (NISAR) mission
Jordan et al. The SIR-C/X-SAR synthetic aperture radar system
Njoku et al. A large-antenna microwave radiometer-scatterometer concept for ocean salinity and soil moisture sensing
Pyne et al. Development and performance evaluation of small SAR system for 100-kg class satellite
Vivekanandan et al. Airborne polarimetric Doppler weather radar: trade-offs between various engineering specifications
Ishii et al. Feasibility study for future space-borne coherent Doppler wind lidar, Part 1: Instrumental Overview for Global Wind Profile Observation
Li et al. Development of the NASA high-altitude imaging wind and rain airborne profiler
RU2429990C1 (ru) Многофункциональная радиолокационная станция высокого разрешения с активной фазированной решеткой для пилотируемых и беспилотных летательных аппаратов
Salah et al. Space weather capabilities of low frequency radio arrays
JP5035782B2 (ja) スプリットビーム方式合成開口レーダ
Liu et al. A combined L-band synthetic aperture radiometer and fan-beam scatterometer for soil moisture and ocean salinity measurement
Anthony et al. Development effort of the airborne lidar simulator for the lidar surface topography (LIST) mission
Hensley et al. Status of a UAVSAR designed for repeat pass interferometry for deformation measurements
Kim et al. Design and implemetation of Compact 77 GHz Synthetic aperture radar for drone based applications
Endemann ADM-Aeolus: the first spaceborne wind lidar
Wei et al. An airborne demonstration for high-resolution wide-swath spaceborne reflector SAR systems
Im et al. System concept for the next-generation spaceborne precipitation radars
Wu et al. Lidar Concept of “Guanlan” Mission for Space Oceanography
CN116165660B (zh) 多频段海洋环境航空综合探测系统
Kuzmin et al. Microwave radiometer-spectrometer MIRS in the space experiment “Convergence”
Singh et al. Space-based lidar
Arcioni et al. Biomass, CoReH 2 O, PREMIER: ESA's candidate 7 th Earth Explorer Missions

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 22752362

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 22752362

Country of ref document: EP

Kind code of ref document: A1