CN103412303A - Communication satellite reflected signal remote sensing monitoring system and monitoring method thereof - Google Patents

Abstract

The invention relates to a communication satellite reflection signal remote sensing monitoring system and a monitoring method thereof, wherein the system includes: a communication satellite that continuously transmits a plurality of direct microwave signals of different working bands; a remote sensing platform; and a reflector installed on the remote sensing platform A signal receiver, which receives the reflected microwave signals after the direct microwave signals of the multiple different working bands are reflected by the ground surface, and performs separation, amplification, analog-to-digital conversion and digital processing on the reflected microwave signals according to the different working bands Afterwards, the one-dimensional power waveforms under the different working bands used for ground object remote sensing monitoring are obtained; and the aluminum plate installed on the top of the reflected signal receiver. In the present invention, because the communication satellite is a geostationary orbit satellite, the observation geometry does not change with time, thereby the shortcoming of the observation geometry change of GNSS-R can be overcome, and because the communication satellite in the present invention provides more operating bands, it can be used in many different fields of application.

Description

A communication satellite reflection signal remote sensing monitoring system and monitoring method thereof

technical field

The invention relates to a communication satellite reflection signal remote sensing monitoring system and a monitoring method thereof.

Background technique

Optical, infrared and microwave remote sensing are the main remote sensing methods for earth observation, and their corresponding sensors work in the visible light, infrared and microwave bands respectively. However, these remote sensing methods have their own limitations, which are briefly summarized as follows: optical and infrared remote sensing are limited to weather conditions, and cannot work all-weather; microwave remote sensing overcomes this shortcoming, and SAR has high spatial resolution, but time resolution cannot. To meet the needs of real-time monitoring, and the cost is high, and passive microwave remote sensing will be limited by the lower spatial resolution.

The emerging GNSS-R (Global Navigation Satellite System—Reflection) remote sensing technology uses the reflected signals of navigation satellites to remotely sense ground objects. Compared with the existing ocean and land surface microwave remote sensing methods such as scatterometer, radar altimeter, and synthetic aperture radar, the navigation satellite group GNSS can continuously provide L-band signals without developing a special transmitter. GNSS-R One receiver can receive multiple satellite signals in the field of view at the same time. It belongs to the dual-station/multi-station radar mode in terms of remote sensing detection mechanism. This working mode can greatly improve the temporal and spatial resolution; Strong L-band, so it can be monitored all day and all day. In addition, the GNSS-R receiver belongs to passive reception and does not need to transmit signals, so the volume and weight are very small, and the required power consumption is also small. Therefore, it has the characteristics of convenience and flexibility in ground object monitoring. GNSS navigation satellites will provide humans with accurate and free detection signals in the next few decades, and the detection signals have long-term stability. means.

As shown in Figure 1, the GNSS-R remote sensing system in the prior art basically includes a plurality of GNSS satellites 1' and a GNSS-R receiver 2', wherein each GNSS satellite 1' continuously transmits L-band direct signals, After being reflected by the ground surface, it is received by a special GNSS-R receiver 2' to form a dual-station/multi-station radar working mode. However, a feature of this GNSS-R remote sensing system is the constantly changing observation geometry, and its working band is only L-band, which limits its remote sensing application. It can be seen that the existing GNSS-R remote sensing system still cannot fully meet the monitoring needs.

Communications satellites are artificial earth satellites used as radio communication relay stations. Communication satellites are used to transmit radio signals to achieve communication between satellite communication earth stations or between earth stations and spacecraft.

China's communication satellites mainly include:

Dongfanghong: Dongfanghong-1 satellite, Dongfanghong-2 satellite, Dongfanghong-3 satellite, Dongfanghong-4 satellite;

Sino: Sino No.1, Sino No.2, Sino No.3, Sino No.4, Sino No.5, Sino No.6;

China Star: China Star 5A, China Star 6B, China Star 8, China Star 9, China Star 10, China Star 11;

Asia Pacific: APSTAR 2R, APSTAR 5, APSTAR 6, APSTAR 7;

Among them, the "Sinuo-6" communication and broadcast satellite is equipped with 24 C-band transponders, 8 Ku-band transponders and 1 S-band transponder. The satellite beam can cover the Asia-Pacific region including the whole of China and some neighboring countries and Therefore, compared with GNSS satellites, "Sinuo-6" has higher power, larger capacity, and wider signal coverage.

Since communication satellites work in the microwave band (C, Ku, and S bands) and have higher signal power, they can become effective microwave transmission sources. At present, only the direct signals of communication satellites are used, and the direct signals are reflected by ground objects. Reflection information has not been used. Therefore, in view of the similarity to GNSS-R remote sensing principles, a communication satellite reflection signal remote sensing monitoring system using communication satellites as an effective source can be developed to provide more operating bands.

Contents of the invention

In order to solve the above-mentioned problems in the prior art, the present invention aims to provide a communication satellite reflection signal remote sensing monitoring system and its monitoring method, so as to overcome the shortcomings of observing geometric changes, and provide multiple working bands to meet the monitoring requirements.

A communication satellite reflection signal remote sensing monitoring system according to one of the present invention, comprising:

Communication satellites that continuously transmit direct microwave signals of multiple different operating bands;

remote sensing platform;

The reflected signal receiver installed on the remote sensing platform, which receives the reflected microwave signals after the direct microwave signals of the multiple different working bands are reflected by the ground surface, and separates the reflected microwave signals according to the different working bands After, after amplification, analog-to-digital conversion and digital processing, one-dimensional power waveform diagrams under the different working bands used for ground object remote sensing monitoring are obtained; and

The aluminum plate installed on the top of the reflected signal receiver reflects the directly received direct microwave signal and transmits the reflected microwave signal directly received from the ground surface to the reflected signal receiver.

In the above-mentioned communication satellite reflection signal remote sensing monitoring system, the reflection signal receiver includes:

A plurality of antenna modules respectively receiving reflected microwave signals in different operating bands;

A plurality of RF front-end modules respectively connected to the antenna module, each of the RF front-end modules receives the reflected microwave signal output by the corresponding antenna module, and amplifies and filters the reflected microwave signal to output a corresponding RF Signal;

A plurality of multi-channel radio frequency receiving modules respectively connected to the radio frequency front-end module, each of the multi-channel radio frequency receiving modules amplifies and filters the corresponding radio frequency signal and outputs a corresponding intermediate frequency signal;

A plurality of high-speed A/D modules respectively connected to the multi-channel radio frequency receiving module, each of the high-speed A/D modules performs analog-to-digital conversion on the corresponding intermediate frequency signal and outputs a corresponding sampling signal;

a plurality of digital processing modules respectively connected to the high-speed A/D module, each of the digital processing modules digitally processes the corresponding sampling signal and outputs corresponding original sampling data; and

A plurality of waveform shaping modules respectively connected to the digital processing module, each of the waveform shaping modules forms a one-dimensional power waveform diagram under different working bands according to corresponding original sampling data.

In the above-mentioned communication satellite reflected signal remote sensing monitoring system, each said antenna module includes a horizontally polarized antenna and a vertically polarized sub-signal respectively for receiving said reflected microwave signal. antenna.

In the above-mentioned communication satellite reflected signal remote sensing monitoring system, each of the RF front-end modules includes sequentially connected:

a transmission path unit, which is used to amplify and filter the reflected microwave signal; and

The receiving path unit is used for performing low-noise amplification and re-filtering on the reflected microwave signal that has been power-amplified and filtered, and outputting the radio frequency signal.

In the above-mentioned communication satellite reflected signal remote sensing monitoring system, the transmission path unit includes a power amplifier and a first filter connected in sequence.

In the above-mentioned communication satellite reflected signal remote sensing monitoring system, the receiving path unit includes a low noise amplifier and a second filter connected in sequence.

In the above remote sensing monitoring system for reflected signals from communication satellites, the digital processing module includes a connected DSP (Digital Signal Processing) chip and FPGA (Field Programmable Gate Array) chip.

In the above communication satellite reflection signal remote sensing monitoring system, the aluminum plate is installed on the top of the reflection signal receiver through a bracket.

A monitoring method based on the above-mentioned communication satellite reflected signal remote sensing monitoring system described in the second aspect of the present invention comprises the following steps:

Step S1, the communication satellite continuously transmits a plurality of direct microwave signals of different working bands;

Step S2, the aluminum plate reflects the directly received direct microwave signal, and transmits the reflected microwave signal of the plurality of direct microwave signals of different working bands directly received from the ground surface to the reflected signal receiver;

Step S3, the reflected signal receiver receives the reflected microwave signals after the direct microwave signals of the plurality of different working bands are reflected by the ground surface, and separates, amplifies, and modifies the reflected microwave signals according to the different working bands After the conversion and digital processing, the one-dimensional power waveform diagrams in the different working bands for remote sensing monitoring of surface objects are obtained.

In the above-mentioned communication satellite reflected signal remote sensing monitoring method, the step S3 includes:

Step S31, respectively receiving reflected microwave signals under the different working bands;

Step S32, respectively amplifying and filtering the reflected microwave signals under the different working bands, and outputting corresponding radio frequency signals;

Step S33, respectively amplifying and filtering the corresponding radio frequency signals, and outputting corresponding intermediate frequency signals;

Step S34, respectively performing analog-to-digital conversion on the corresponding intermediate frequency signals, and outputting corresponding sampling signals;

Step S35, performing digital processing on the corresponding sampling signals, and outputting corresponding original sampling data; and

Step S36, forming one-dimensional power waveform diagrams under different working bands according to the corresponding original sampling data.

Due to the above-mentioned technical solution, the present invention uses the microwave signal emitted by the existing communication satellite as the signal source, and the signal is reflected by the ground surface and received by the reflected signal receiver, thereby realizing remote sensing monitoring of the ground. Different from the existing GNSS-R remote sensing monitoring method, since the communication satellite is a geostationary orbit satellite, the observation geometry does not change with time, which can overcome the shortcomings of the GNSS-R observation geometry change, and compared with only providing L-band For the GNSS-R remote sensing system, the communication satellites in the present invention (such as Xinuo No. 6) provide more working bands (such as C band, Ku band and S band), and for different working bands, the soil moisture , vegetation, snow cover and other ground object parameters have different detection capabilities, therefore, the present invention can be used in many different application fields.

Description of drawings

Fig. 1 is the structural representation of the GNSS-R remote sensing system in the prior art;

Fig. 2 is the structural representation of a kind of communication satellite reflected signal remote sensing monitoring system of the present invention;

Fig. 3 is a structural schematic diagram of a reflection signal receiver in a communication satellite reflection signal remote sensing monitoring system of the present invention.

Detailed ways

Below in conjunction with the drawings, preferred embodiments of the present invention are given and described in detail.

As shown in Figures 2 and 3, the present invention, that is, a communication satellite reflection signal remote sensing monitoring system, includes:

A communication satellite 1 that continuously transmits multiple direct microwave signals in different operating bands;

Remote Sensing Platform 2;

The reflected signal receiver 3 installed on the remote sensing platform 2 receives the reflected microwave signals after the direct microwave signals of multiple working bands are reflected by the ground surface, and separates, amplifies, and converts the reflected microwave signals according to different working bands After digital processing, the one-dimensional power waveforms under different working bands for ground object remote sensing monitoring are obtained; and

The aluminum plate 4 installed on the top of the reflected signal receiver 3 through the bracket 5 reflects the directly received direct microwave signal and transmits the reflected microwave signal directly received from the ground surface to the reflected signal receiver 3 .

Reflected signal receiver 3 among the present invention specifically comprises:

A plurality of antenna modules 31 that respectively receive reflected microwave signals in different operating bands; specifically, each antenna module 31 includes horizontal (H) polarimetric sub-signals and vertical (V) poles for receiving reflected microwave signals, respectively. A horizontally polarized antenna 311 and a vertically polarized antenna 312 for sub-signals;

A plurality of radio frequency front-end modules 32 respectively connected to the antenna module 31 (the radio frequency front-end module 32 is close to the antenna module 31), each radio frequency front-end module 32 receives the reflected microwave signal output by the corresponding antenna module 31, and amplifies the reflected microwave signal Output the corresponding radio frequency signal after filtering; Specifically, each radio frequency front-end module 32 comprises sequentially connected: transmit path unit 321, it comprises the power amplifier 3211 and the first filter 3212 that are connected in sequence, for reflecting microwave signal Perform power amplification and filtering; and a receiving path unit 322, which includes a low noise amplifier 3221 (LNA) and a second filter 3222 connected in sequence, for performing low noise amplification and filtering on the reflected microwave signal that has been power amplified and filtered Filtering again, so as to ensure that the useful RF signal can be effectively transmitted to the downstream circuit;

A plurality of multi-channel radio frequency receiving modules 33 respectively connected to the radio frequency front-end module 32, each multi-channel radio frequency receiving module 33 outputs corresponding intermediate frequency signals after amplifying and filtering corresponding radio frequency signals;

A plurality of high-speed A/D modules 34 connected to the multi-channel radio frequency receiving module 33 respectively, each high-speed A/D module 34 outputs corresponding sampling signals after carrying out analog-to-digital conversion to corresponding intermediate frequency signals;

A plurality of digital processing modules 35 connected to the high-speed A/D module 34 respectively, each digital processing module 35 outputs corresponding original sampling data after digitally processing the corresponding sampling signal; specifically, each digital processing module 35 includes connected DSP chip 351 and FPGA chip 352; and

A plurality of waveform shaping modules 36 respectively connected to the digital processing module 35, each waveform shaping module 36 forms a one-dimensional power waveform diagram under different working bands according to corresponding original sampling data.

The monitoring method based on the above-mentioned remote sensing monitoring system for reflected signals from communication satellites comprises the following steps:

Step S1, the communication satellite 1 continuously transmits a plurality of direct microwave signals of different working bands;

Step S2, the aluminum plate 4 reflects the directly received direct microwave signals, and transmits the reflected microwave signals of direct microwave signals of multiple different working bands directly received from the ground to the reflected signal receiver 3;

In step S3, the reflected signal receiver 3 receives multiple reflected microwave signals reflected by the ground surface from direct microwave signals of different operating bands, and performs separation, amplification, analog-to-digital conversion and digital processing on the reflected microwave signals according to different operating bands to obtain One-dimensional power waveform diagram under different working bands for remote sensing monitoring of surface objects.

The above step S3 specifically includes:

Step S31, receiving reflected microwave signals in different operating bands through multiple antenna modules 31;

Step S32, amplifying and filtering reflected microwave signals in different operating bands through multiple radio frequency front-end modules 32, and outputting corresponding radio frequency signals;

Step S33, respectively amplifying and filtering corresponding radio frequency signals through a plurality of multi-channel radio frequency receiving modules 33, and outputting corresponding intermediate frequency signals;

Step S34, through a plurality of high-speed A/D modules 34, respectively perform analog-to-digital conversion on corresponding intermediate frequency signals, and output corresponding sampling signals;

Step S35, digitally process corresponding sampling signals through a plurality of digital processing modules 35, and output corresponding original sampling data; and

In step S36, a plurality of waveform shaping modules 36 are used to form one-dimensional power waveform diagrams in different operating bands according to the corresponding original sampling data.

Taking the existing "Xinuo No. 6" communication satellite as an example, the working principle of the present invention will be described again below.

"Sinuo-6" continuously transmits direct microwave signals in the C-band, Ku-band and S-band. These direct microwave signals are reflected by the ground surface and then received by the reflected microwave signal receiver 3 mounted on the remote sensing platform 2. In the system Since the aluminum plate 4 can undergo total reflection, the direct microwave signal directly incident on the surface of the aluminum plate 4 will be completely reflected, and will not be received by the reflected signal receiver 3. At the same time, the reflected microwave signal after the direct microwave signal is reflected by the surface If it is directly received by the aluminum plate 4, it can also be received by the reflected signal receiver 3 after being reflected by the aluminum plate 4, thereby ensuring that the reflected signal receiver 3 only receives the reflected microwave signal reflected by the ground surface, and will not receive the direct microwave signal . The reflected signal receiver 3 can simultaneously receive the reflected microwave signals of the C, Ku and S bands of "Sinuo No. 6" through the three antenna modules 31, and after receiving the reflected microwave signal, the After the other modules separate, amplify, analog-to-digital convert and digitally process the reflected microwave signals under the three operating bands, they can obtain one-dimensional power waveforms of C-band, Ku-band and S-band, and finally use these power waveforms to perform Ground object remote sensing monitoring.

In summary, the present invention has the following beneficial effects:

1, the present invention uses the signal that existing communication satellite transmits as transmission source, adopts special reflection signal receiver to receive the reflection signal of communication satellite; Compared with microwave sensors such as existing microwave radiometer and radar, this kind The remote sensing monitoring system has low cost, low power consumption, simple operation and flexible maneuverability;

2. Compared with the existing GNSS-R receiver, since the communication satellite is a geostationary orbit satellite, the observation geometry of the remote sensing system formed by the reflected signal receiver of the present invention is fixed, which overcomes the observation of the GNSS-R remote sensing monitoring system. The disadvantage of constantly changing geometry;

3. Compared with the L band of the existing GNSS-R remote sensing monitoring system, the remote sensing monitoring system of the present invention has more working bands (such as microwave bands including communication satellites such as C, Ku and S bands), therefore, it can be applied In a variety of different fields, the detection of various ground object parameters is realized.

What is described above is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Various changes can also be made to the above embodiments of the present invention. That is to say, all simple and equivalent changes and modifications made according to the claims and description of the application for the present invention fall within the protection scope of the claims of the patent of the present invention. What is not described in detail in the present invention is conventional technical contents.

Claims (10)

1. A communication satellite reflected signal remote sensing monitoring system, characterized in that the system comprises: Communication satellites that continuously transmit direct microwave signals of multiple different operating bands; remote sensing platform; The reflected signal receiver installed on the remote sensing platform, which receives the reflected microwave signals after the direct microwave signals of the multiple different working bands are reflected by the ground surface, and separates the reflected microwave signals according to the different working bands After, after amplification, analog-to-digital conversion and digital processing, one-dimensional power waveform diagrams under the different working bands used for ground object remote sensing monitoring are obtained; and The aluminum plate installed on the top of the reflected signal receiver reflects the directly received direct microwave signal and transmits the reflected microwave signal directly received from the ground surface to the reflected signal receiver. 2. communication satellite reflected signal remote sensing monitoring system according to claim 1, is characterized in that, described reflected signal receiver comprises: A plurality of antenna modules respectively receiving reflected microwave signals in different operating bands; A plurality of RF front-end modules respectively connected to the antenna module, each of the RF front-end modules receives the reflected microwave signal output by the corresponding antenna module, and amplifies and filters the reflected microwave signal to output a corresponding RF Signal; A plurality of multi-channel radio frequency receiving modules respectively connected to the radio frequency front-end module, each of the multi-channel radio frequency receiving modules amplifies and filters the corresponding radio frequency signal and outputs a corresponding intermediate frequency signal; A plurality of high-speed A/D modules respectively connected to the multi-channel radio frequency receiving module, each of the high-speed A/D modules performs analog-to-digital conversion on the corresponding intermediate frequency signal and outputs a corresponding sampling signal; A plurality of digital processing modules respectively connected to the high-speed A/D module, each of the digital processing modules digitally processes the corresponding sampling signal and outputs corresponding original sampling data; and A plurality of waveform shaping modules respectively connected to the digital processing module, each of the waveform shaping modules forms a one-dimensional power waveform diagram under different working bands according to corresponding original sampling data. 3. The communication satellite reflected signal remote sensing monitoring system according to claim 2, wherein each said antenna module includes a horizontal polarimetric signal and a vertical polarimetric signal respectively used for receiving said reflected microwave signal A horizontally polarized antenna and a vertically polarized antenna. 4. communication satellite reflected signal remote sensing monitoring system according to claim 2, is characterized in that, each described RF front-end module comprises sequentially connected: a transmission path unit, which is used to amplify and filter the reflected microwave signal; and The receiving path unit is used for performing low-noise amplification and re-filtering on the reflected microwave signal that has been power-amplified and filtered, and outputting the radio frequency signal. 5. The communication satellite reflected signal remote sensing monitoring system according to claim 4, characterized in that, the transmitting path unit comprises a power amplifier and a first filter connected in sequence. 6. The communication satellite reflected signal remote sensing monitoring system according to claim 4 or 5, characterized in that, the receiving path unit includes a low noise amplifier and a second filter connected in sequence. 7. The communication satellite reflected signal remote sensing monitoring system according to claim 2, characterized in that, said digital processing module comprises connected DSP chips and FPGA chips. 8. The communication satellite reflected signal remote sensing monitoring system according to claim 1 or 2, characterized in that the aluminum plate is installed on the top of the reflected signal receiver through a bracket. 9. A monitoring method based on the communication satellite reflected signal remote sensing monitoring system according to claim 1, wherein the method comprises the following steps: Step S1, the communication satellite continuously transmits a plurality of direct microwave signals of different working bands; Step S2, the aluminum plate reflects the directly received direct microwave signal, and transmits the reflected microwave signal of the plurality of direct microwave signals of different working bands directly received from the ground surface to the reflected signal receiver; Step S3, the reflected signal receiver receives the reflected microwave signals after the direct microwave signals of the multiple different working bands are reflected by the ground surface, and separates, amplifies, and modifies the reflected microwave signals according to the different working bands After conversion and digital processing, the one-dimensional power waveform diagrams in the different working bands for remote sensing monitoring of surface objects are obtained. 10. The communication satellite reflected signal remote sensing monitoring method according to claim 9, wherein said step S3 comprises: Step S31, respectively receiving the reflected microwave signals under the different working bands; Step S32, respectively amplifying and filtering the reflected microwave signals under the different working bands, and outputting corresponding radio frequency signals; Step S33, respectively amplifying and filtering the corresponding radio frequency signals, and outputting corresponding intermediate frequency signals; Step S34, respectively performing analog-to-digital conversion on the corresponding intermediate frequency signals, and outputting corresponding sampling signals; Step S35, performing digital processing on the corresponding sampling signals, and outputting corresponding original sampling data; and Step S36, forming one-dimensional power waveform diagrams in different working bands according to the corresponding original sampling data.

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