Electromagnetic Compatibility Verification Method and System for SAR Payload and Satellite Platform Radio Frequency Equipment

Abstract

This invention relates to a method and system for verifying the electromagnetic compatibility (EMC) of a SAR payload and satellite platform radio frequency (RF) equipment across an entire satellite. The method involves performing power-on self-tests on the satellite platform RF equipment, the integrated payload electronics, the SAR payload, and the system comprised of the satellite platform RF equipment and the integrated payload electronics. The method sets the beam pointing angle of the SAR payload and the beam scanning angle of the satellite platform RF equipment, records the received noise of the SAR payload, and determines the impact of the satellite platform RF equipment on the SAR payload based on the noise test results. By using a SAR antenna subarray instead of the full array, the impact of the satellite platform RF equipment on the SAR payload is quantitatively verified, thus solving the problem of the inability to quantify the impact of the SAR payload during whole-satellite testing. This ensures the verification of the entire satellite's RF compatibility, reduces the risks and costs of satellite development, and meets schedule requirements.

Description

Technical Field

[0001] This invention relates to the field of satellite electromagnetic compatibility testing technology, and in particular to a whole-satellite verification method and system for electromagnetic compatibility of SAR payload and satellite platform radio frequency equipment. Background Technology

[0002] The primary payload of a SAR satellite is the SAR payload itself. This payload is an active microwave remote sensing device operating in the Ku band, with high transmit power and high receive sensitivity. Because the payload platform is a small satellite platform with limited onboard space, and the payload's antenna gain is high, the antenna size is large, limiting the distance between the payload antenna and the platform antenna, resulting in strong coupling between the antennas. Therefore, electromagnetic compatibility testing and verification between the SAR payload and the platform's radio frequency equipment is crucial for ensuring satellite performance.

[0003] Electromagnetic compatibility (EMC) testing during the satellite integration phase aims to verify the EMC of the platform and payload equipment under satellite-wide environmental conditions. The design and verification process for satellite EMC is as follows: Figure 1 As shown, the process mainly includes the design phase, prototype phase, satellite-wide EMC testing phase, and final product phase. The design phase completes the satellite-wide EMC design specifications, serving as the basic requirements for the EMC design of each subsystem. The prototype phase completes the radiated model satellite (antenna isolation) testing and simultaneously completes the equipment-level (prototype product) EMC tests required by the satellite-wide design specifications. After the satellite as a whole completes product acceptance, satellite-wide EMC testing is conducted, including satellite-wide electrical tests and simulated flight tests. Satellite-wide EMC testing can be divided into conducted tests and radiated tests. Conducted tests mainly verify EMC caused by conduction through cables, including ripple and surge, while radiated tests mainly verify EMC caused by unintentional radiation from antenna terminals, flanges, equipment housings, and cables.

[0004] Currently, the traditional method for verifying the radio frequency compatibility (RF) of a satellite during the prototype stage is for the equipment manufacturer to develop a prototype and participate in the satellite's electromagnetic compatibility (EMC) test. While this method provides a relatively complete picture, the load data output by the load subsystem at this stage is difficult to quantify and describe the impact of the platform's RF equipment on the load. Summary of the Invention

[0005] To address the technical problems existing in the prior art, the present invention aims to provide a method and system for verifying the electromagnetic compatibility of SAR payloads and satellite platform radio frequency equipment, which can realize the complete verification of the radio frequency compatibility of the prototype satellite.

[0006] To achieve the above-mentioned objectives, this invention provides a whole-satellite verification method for the electromagnetic compatibility of SAR payloads and satellite platform radio frequency equipment, comprising the following steps:

[0007] Step S1: Perform a power-on self-test on the load integration electronics, determine and record the working status of the load integration electronics;

[0008] Step S2: Perform a power-on self-test on the satellite platform radio frequency equipment, determine and record the working status of the satellite platform radio frequency equipment;

[0009] Step S3: Connect the payload integrated electronics and the satellite platform radio frequency equipment to form a satellite platform radio frequency system;

[0010] Step S4: Set the beam pointing angle of the satellite platform radio frequency equipment according to the self-test angle of the satellite platform radio frequency equipment, perform a power-on self-test on the satellite platform radio frequency system, and determine and record the working status of the satellite platform radio frequency system;

[0011] Step S5: Set the beam pointing angle of the SAR payload according to the SAR payload self-test angle, perform a power-on self-test on the SAR payload, and record the working status of the SAR payload product.

[0012] Step S6: According to the overall satellite layout, install the SAR payload, the payload integrated electronics, and the satellite platform radio frequency equipment on the simulated satellite board and connect them to the network, and control them to be in normal working mode.

[0013] Step S7: Set the SAR payload beam pointing angle according to the SAR payload self-test angle, continuously observe the receiving noise floor of the SAR payload, test and record the SAR payload receiving noise data, and form the first receiving noise data table.

[0014] Step S8: Set the beam pointing angle of the satellite platform radio frequency equipment according to the self-test angle of the satellite platform radio frequency equipment, test and record the receiving noise of the SAR payload, and form a second receiving noise data table;

[0015] Step S9: Repeat step S8 until all SAR payload beam pointing angles of the SAR payload are traversed.

[0016] Step S10: Quantify the electromagnetic compatibility of the satellite platform radio frequency equipment and payload by comparing the first received noise data table and the second received noise data table.

[0017] According to one technical solution of the present invention, the satellite platform radio frequency equipment is a data transmission phased array antenna.

[0018] According to one technical solution of the present invention, in step S4, the self-test angle of the satellite platform radio frequency equipment is set as follows:

[0019] The beam scanning angle of the data transmission phased array antenna is set with an azimuth angle of 0 degrees to 360 degrees, an off-axis angle of 0 degrees to 67.5 degrees, and a step of 5 degrees.

[0020] According to one technical solution of the present invention, in step S5, the SAR payload self-test angle is set as follows:

[0021] The beam pointing angle of the SAR payload is set to ±7.5 degrees in the azimuth direction, -55 to 55 degrees in the range direction, and a step of 5 degrees, and then a self-test is performed.

[0022] According to one technical solution of the present invention, step S7 specifically includes:

[0023] The SAR payload is powered on, and the SAR payload self-test angle is set to the SAR payload beam pointing angle. The state is maintained for t seconds at each angle, and the receiving noise floor of the SAR payload is continuously observed. The SAR payload receiving noise data is tested and recorded to form the first receiving noise data table.

[0024] According to one technical solution of the present invention, step S8 specifically includes:

[0025] The SAR payload is powered on, and the beam pointing angle of the SAR payload is set according to the SAR payload self-test angle. Under the beam pointing angle set by the SAR payload, the data transmission phased array antenna sets its beam scanning angle according to the self-test angle of the satellite platform radio frequency equipment. Each beam pointing angle is held for t seconds. The noise data received by the SAR payload is tested and recorded to form a second received noise data table.

[0026] According to one technical solution of the present invention, the operating state of the SAR payload product includes: operating voltage, operating current, antenna beam azimuth angle, and antenna beam range angle;

[0027] The first received noise data table and the second received noise data table include: frequency and its corresponding noise amplitude.

[0028] According to one technical solution of the present invention, step S10 specifically includes:

[0029] The frequencies in the first received noise data table are represented as f1, f2, ... f K The corresponding noise amplitudes are represented as N1, N2, ..., N K ;

[0030] The frequencies in the second received noise data table are represented as f1, f2, ... f K The corresponding noise amplitudes are represented as N'1, N'2, ..., N' K ;

[0031] The noise consistency factor is calculated based on the first received noise data table and the second received noise data table. The formula for calculating the noise consistency factor is as follows:

[0032]

[0033] Wherein, K represents the number of frequencies in the first received noise data table and the second received noise data table;

[0034] If the calculated noise consistency factor does not exceed the noise consistency threshold, the SAR payload is determined to be compatible with the satellite platform radio frequency equipment; otherwise, they are determined to be incompatible.

[0035] According to one aspect of the present invention, a system for implementing the above-described method for verifying the electromagnetic compatibility of SAR payload and satellite platform radio frequency equipment, includes the satellite platform radio frequency equipment, the payload integration electronics, and the SAR payload, wherein the payload integration electronics are electrically connected to the satellite platform radio frequency equipment, and further includes:

[0036] A power supply unit is used to supply power to the payload integrated electronics, the satellite platform radio frequency equipment, and the SAR payload;

[0037] The first ground detection system is connected to the payload integrated electronics and the satellite platform radio frequency equipment, and is used to control the payload integrated electronics and the satellite platform radio frequency equipment;

[0038] The second ground detector is electrically connected to the SAR payload and is used to control the SAR payload;

[0039] A simulated satellite plate is used to mount the integrated payload electronics, the satellite platform radio frequency equipment, and the SAR payload, and to perform whole-satellite simulation; the antennas of the satellite platform radio frequency equipment and the SAR payload are arranged opposite to each other on the simulated satellite plate.

[0040] Compared with the prior art, the present invention has the following beneficial effects:

[0041] This invention proposes a method and system for verifying the electromagnetic compatibility (EMC) of SAR payloads and satellite platform radio frequency equipment across the entire satellite. By verifying the EMC of the payload's integrated electronics, satellite platform radio frequency equipment, and SAR payload, and by recording and comparing noise data received by the SAR payload at different self-test angles, interference can be identified and located. This solves the problem of the inability to quantify the impact of SAR on the radio frequency compatibility of the entire satellite during testing, reduces the risk and cost of satellite development, and meets schedule requirements. Furthermore, through testing and analysis, more data can be accumulated for application in the development of subsequent models.

[0042] This invention obtains the input noise on the SAR payload system RF link after the SAR payload subarray by testing the electromagnetic noise emitted by the satellite platform RF equipment received by the SAR payload subarray. Compared with the inherent noise of the SAR payload system, the degree of noise degradation, that is, the degree of impact, can be directly quantified. This not only simplifies the testing method but also greatly shortens the test time. Attached Figure Description

[0043] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly described below. Obviously, the drawings described below are merely some embodiments of the present invention, and those skilled in the art can obtain other drawings based on these drawings without creative effort.

[0044] Figure 1 A flowchart illustrating the design and verification of the electromagnetic compatibility of the entire satellite;

[0045] Figure 2 This schematic diagram illustrates the structure of the whole-satellite verification system for electromagnetic compatibility of SAR payload and satellite platform radio frequency equipment provided by the present invention.

[0046] Figure 3 The flowchart illustrates the whole-satellite verification method for electromagnetic compatibility of SAR payload and satellite platform radio frequency equipment according to the present invention. Detailed Implementation

[0047] The description of the embodiments in this specification should be taken in conjunction with the accompanying drawings, which should form part of the complete specification. In the drawings, the shape or thickness of the embodiments may be exaggerated and may be indicated in a simplified or convenient manner. Furthermore, parts of the various structures in the drawings will be described separately; it is worth noting that elements not shown in the figures or not described in words are in a form known to those skilled in the art.

[0048] The descriptions of the embodiments herein, including any references to directions and orientations, are for ease of description only and should not be construed as limiting the scope of the invention. The following description of preferred embodiments involves combinations of features, which may exist independently or in combination; the invention is not particularly limited to the preferred embodiments. The scope of the invention is defined by the claims.

[0049] like Figure 2As shown, this invention provides a system for verifying the electromagnetic compatibility of a SAR payload with a satellite platform radio frequency (RF) device. The system includes a satellite platform RF device, a payload integration electronics 2, and a SAR payload 3. The satellite platform RF device is a data transmission phased array antenna 1. The payload integration electronics 2 is electrically connected to the data transmission phased array antenna 1. The system also includes:

[0050] Power supply unit 4 is used to supply power to payload integrated electronics 2, data transmission phased array antenna 1 and SAR payload 3;

[0051] The first ground detection 5 is connected to the load integrated electronics 2 and the data transmission phased array antenna 1, and is used to control the load integrated electronics 2 and the data transmission phased array antenna 1;

[0052] The second ground detection 6 is electrically connected to the SAR payload 3 and is used to control the SAR payload 3;

[0053] The simulated satellite plate (not shown in the figure) is used to install the integrated payload electronics 2, the data transmission phased array antenna 1 and the SAR payload 3, and to perform whole-satellite simulation; the antennas of the data transmission phased array antenna 1 and the SAR payload 2 are set opposite to each other on the simulated satellite plate.

[0054] like Figure 3 As shown, the present invention provides a whole-satellite verification method for electromagnetic compatibility of SAR payload and satellite platform radio frequency equipment, comprising the following steps:

[0055] Step S1: Perform a power-on self-test on the load integration electronics, determine and record the working status of the load integration electronics;

[0056] Connect the internal cable of the load integration electronics 2, connect the cable between the load integration electronics 2 and the first ground test 5, complete the power-on self-test of the equipment, record the product working status of the load integration electronics 2, and determine whether its operation is normal.

[0057] Step S2: Perform a power-on self-test on the satellite platform radio frequency equipment, compare the measured values ​​of telemetry parameters with the design values, and determine and record the working status of the satellite platform radio frequency equipment.

[0058] Connect the cable between the data transmission phased array antenna 1 and the first ground tester 5 to complete the equipment power-on self-test, record the product working status of the data transmission phased array antenna 1, and determine whether its operation is normal.

[0059] Step S3: Connect the payload integrated electronics and satellite platform radio frequency equipment to form the satellite platform radio frequency system;

[0060] Step S4: Set the beam pointing angle of the satellite platform radio frequency equipment according to the self-test angle of the satellite platform radio frequency equipment, perform a power-on self-test on the satellite platform radio frequency system, and determine and record the working status of the satellite platform radio frequency system.

[0061] The self-test angle of the satellite platform radio frequency equipment is set as follows: the beam scanning angle of the data transmission phased array antenna 1 is set with an azimuth angle of 0 degrees to 360 degrees, an off-axis angle of 0 degrees to 67.5 degrees, and a step of 5 degrees.

[0062] The payload integrated electronics 2 and the data transmission phased array antenna 1 are powered on, and the system self-test is completed. The beam scanning angle of the data transmission phased array antenna 1 is set according to the azimuth angle of 0 degrees to 360 degrees, the off-axis angle of 0 degrees to 67.5 degrees, and the step of 5 degrees. The normal working status of the equipment is judged by telemetry.

[0063] Step S5: Set the beam pointing angle of the SAR payload according to the SAR payload self-test angle, perform a power-on self-test on the SAR payload, and record the working status of the SAR payload product.

[0064] The product operating status of the SAR payload includes operating voltage (V), operating current (A), antenna beam azimuth angle (degrees), and antenna beam range angle (degrees).

[0065] The SAR payload self-test angle is set as follows: the beam pointing angle of the SAR payload is set to ±7.5 degrees in the azimuth direction, -55 to 55 degrees in the range direction, and in 5-degree increments.

[0066] Power on SAR payload 3, set the beam pointing angle of SAR payload 3 according to the azimuth angle of ±7.5 degrees and the range angle of -55 to 55 degrees (in 5-degree steps), perform self-test, record the working status of SAR payload product, and determine whether the working is normal.

[0067] Step S6: According to the overall satellite layout, install the SAR payload, payload integrated electronics and satellite platform radio frequency equipment on the simulated satellite board and connect the wires, and control it to be in normal working mode.

[0068] Based on the overall satellite layout, the SAR payload 3 and the data transmission phased array antenna 1 are mounted on the simulated satellite board. The power supply and control cables for the SAR payload 3, payload electronics 2, and data transmission phased array antenna 1 are connected. The SAR payload 3, payload electronics 2, and data transmission phased array antenna 1 are controlled to operate in normal working mode via the first ground detector 5 and the second ground detector 6.

[0069] Step S7: Set the SAR payload beam pointing angle according to the SAR payload self-test angle, continuously observe the receiving noise floor of the SAR payload, test and record the SAR payload receiving noise data, and form the first receiving noise data table.

[0070] SAR payload 3 is powered on and switched sequentially according to the self-test angle. The state is maintained for t seconds at each angle. The receiving noise floor of SAR payload 3 is continuously observed, and the first noise data table is tested and recorded.

[0071] Step S8: Set the beam pointing angle of the satellite platform radio frequency equipment according to the self-test angle of the satellite platform radio frequency equipment, test and record the received noise of the SAR payload, and form a second received noise data table.

[0072] SAR payload 3 is powered on, and the SAR payload beam pointing angle is set according to the self-test angle. Under the SAR payload pointing angle setting, the data transmission phased array antenna 1 is set according to its own self-test beam pointing angle. Each beam pointing angle is maintained for t seconds (t seconds is the time for the payload to complete one reception). The second noise data table is tested and recorded.

[0073] Step S9: Repeat step S8 until all SAR payload beam pointing angles of the SAR payload have been traversed.

[0074] Step S10: Quantify the electromagnetic compatibility of the satellite platform radio frequency equipment and payload by comparing the first and second received noise data tables.

[0075] Table 1 First Received Noise Data Table

[0076] Frequency (GHz) <![CDATA[f1]]> <![CDATA[f2]]> … <![CDATA[f K ]]> Noise amplitude (dBm / Hz) <![CDATA[N1]]> <![CDATA[N2]]> … <![CDATA[N K ]]>

[0077] Table 2 Second Received Noise Data Table

[0078] Frequency (GHz) <![CDATA[f1]]> <![CDATA[f2]]> … <![CDATA[f K ]]> Noise amplitude (dBm / Hz) <![CDATA[N′1]]> <![CDATA[N′2]]> … <![CDATA[N′ K ]]>

[0079] The noise consistency factor is calculated based on the first and second received noise data tables. The formula for calculating the noise consistency factor is as follows:

[0080]

[0081] Where K represents the number of frequencies in the first and second received noise data tables.

[0082] If C≤0.5, the noise consistency between the two tests is good, and the satellite platform RF equipment does not cause noise degradation of the load, indicating that the two are electromagnetically compatible. Otherwise, it indicates that the satellite platform RF equipment will cause noise degradation of the load when powered on, indicating that the two are incompatible.

[0083] Therefore, by comparing the first and second received noise data tables, the impact of the satellite platform's radio frequency equipment on the payload can be determined, and the quantitative analysis results of the payload performance can be obtained, thereby verifying the electromagnetic compatibility of the satellite platform's radio frequency equipment and the payload.

[0084] Using the above method, the SAR payload and data transmission phased array antenna can be installed on the satellite simulation board according to the actual satellite mounting location. The SAR payload and data transmission phased array antenna are powered on simultaneously, the direction of the data transmission phased array antenna is adjusted, and the noise received by the payload is tested, thereby completing the full verification of the radio frequency compatibility of the prototype satellite.

[0085] It should be noted that the above description represents a preferred embodiment of the present invention. While preferred embodiments have been described, those skilled in the art, upon understanding the basic inventive concept of the present invention, can make various improvements and modifications without departing from the principles described herein. These improvements and modifications should also be considered within the scope of protection of the present invention. Therefore, the appended claims are intended to include both the preferred embodiments and all changes and modifications falling within the scope of the embodiments of the present invention.

Claims

1. A satellite-wide verification method for the electromagnetic compatibility of SAR payloads and satellite platform radio frequency equipment, characterized in that, Includes the following steps: Step S1: Perform a power-on self-test on the load integration electronics, determine and record the working status of the load integration electronics; Step S2: Perform a power-on self-test on the satellite platform radio frequency equipment, determine and record the working status of the satellite platform radio frequency equipment; Step S3: Connect the payload integrated electronics and the satellite platform radio frequency equipment to form a satellite platform radio frequency system; Step S4: Set the beam pointing angle of the satellite platform radio frequency equipment according to the self-test angle of the satellite platform radio frequency equipment, perform a power-on self-test on the satellite platform radio frequency system, and determine and record the working status of the satellite platform radio frequency system; Step S5: Set the beam pointing angle of the SAR payload according to the SAR payload self-test angle, perform a power-on self-test on the SAR payload, and record the working status of the SAR payload product. Step S6: According to the overall satellite layout, install the SAR payload, the payload integrated electronics, and the satellite platform radio frequency equipment on the simulated satellite board and connect them to the network, and control them to be in normal working mode. Step S7: Set the SAR payload beam pointing angle according to the SAR payload self-test angle, continuously observe the receiving noise floor of the SAR payload, test and record the SAR payload receiving noise data, and form the first receiving noise data table. Step S8: Set the beam pointing angle of the satellite platform radio frequency equipment according to the self-test angle of the satellite platform radio frequency equipment, test and record the received noise of the SAR payload, and form a second received noise data table; Step S9: Repeat step S8 until all SAR payload beam pointing angles of the SAR payload are traversed. Step S10: By comparing the first received noise data table and the second received noise data table, a quantitative analysis of the electromagnetic compatibility of the satellite platform radio frequency equipment and SAR payload is performed.

2. The whole-satellite verification method for electromagnetic compatibility of SAR payload and satellite platform radio frequency equipment according to claim 1, characterized in that, The satellite platform's radio frequency equipment is a data transmission phased array antenna.

3. The whole-satellite verification method for electromagnetic compatibility of SAR payload and satellite platform radio frequency equipment according to claim 2, characterized in that, In step S4, the self-test angle of the satellite platform radio frequency equipment is set as follows: The beam scanning angle of the data transmission phased array antenna is set with an azimuth angle of 0 degrees to 360 degrees, an off-axis angle of 0 degrees to 67.5 degrees, and a step of 5 degrees.

4. The whole-satellite verification method for electromagnetic compatibility of SAR payload and satellite platform radio frequency equipment according to claim 3, characterized in that, In step S5, the SAR payload self-test angle is set as follows: The beam pointing angle of the SAR payload is set to ±7.5 degrees in the azimuth direction, -55 to 55 degrees in the range direction, and a step of 5 degrees, and then a self-test is performed.

5. The whole-satellite verification method for electromagnetic compatibility of SAR payload and satellite platform radio frequency equipment according to claim 4, characterized in that, Step S7 specifically includes: The SAR payload is powered on, and the SAR payload self-test angle is set to the SAR payload beam pointing angle. The state is maintained for t seconds at each angle, and the receiving noise floor of the SAR payload is continuously observed. The SAR payload receiving noise data is tested and recorded to form the first receiving noise data table.

6. The whole-satellite verification method for electromagnetic compatibility of SAR payload and satellite platform radio frequency equipment according to claim 5, characterized in that, Step S8 specifically includes: The SAR payload is powered on, and the beam pointing angle of the SAR payload is set according to the SAR payload self-test angle. Under the beam pointing angle set by the SAR payload, the data transmission phased array antenna sets its beam scanning angle according to the self-test angle of the satellite platform radio frequency equipment. Each beam pointing angle is held for t seconds. The noise data received by the SAR payload is tested and recorded to form a second received noise data table.

7. The whole-satellite verification method for electromagnetic compatibility of SAR payload and satellite platform radio frequency equipment according to claim 1, characterized in that, The operating status of the SAR payload product includes: operating voltage, operating current, antenna beam azimuth angle, and antenna beam range angle. The first received noise data table and the second received noise data table include frequencies and their corresponding noise amplitudes.

8. The whole-satellite verification method for electromagnetic compatibility of SAR payload and satellite platform radio frequency equipment according to claim 7, characterized in that, Step S10 specifically includes: The frequencies in the first received noise data table are represented as f1, f2, ... f K The corresponding noise amplitudes are represented as N1, N2, ..., N K ; The frequencies in the second received noise data table are represented as f1, f2, ... f K The corresponding noise amplitudes are represented as N'1, N'2, and N'3. ··· 、N' K ; The noise consistency factor is calculated based on the first received noise data table and the second received noise data table. The formula for calculating the noise consistency factor is as follows: Wherein, K represents the number of frequencies in the first received noise data table and the second received noise data table; If the calculated noise consistency factor does not exceed the noise consistency threshold, the SAR payload is determined to be compatible with the satellite platform radio frequency equipment; otherwise, they are determined to be incompatible.

9. A system for implementing the whole-satellite verification method for electromagnetic compatibility of SAR payload and satellite platform radio frequency equipment as described in any one of claims 1 to 8, characterized in that, The system includes the satellite platform radio frequency equipment, the payload integration electronics, and the SAR payload, wherein the payload integration electronics are electrically connected to the satellite platform radio frequency equipment, and further includes: A power supply unit is used to supply power to the payload integrated electronics, the satellite platform radio frequency equipment, and the SAR payload; The first ground detection system is connected to the payload integrated electronics and the satellite platform radio frequency equipment, and is used to control the payload integrated electronics and the satellite platform radio frequency equipment; The second ground detector is electrically connected to the SAR payload and is used to control the SAR payload; A simulated satellite plate is used to mount the integrated payload electronics, the satellite platform radio frequency equipment, and the SAR payload, and to perform whole-satellite simulation; the antennas of the satellite platform radio frequency equipment and the SAR payload are arranged opposite to each other on the simulated satellite plate.

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