Satellite-borne double-frequency meteorological radar vacuum thermal test device and test method

Abstract

The invention provides a satellite-borne double-frequency weather radar vacuum thermal test device and method, and the device comprises a first radar, a second radar, a first radar installation support, a second radar installation support, a first wave-absorbing heat sink cover, a second wave-absorbing heat sink cover, an in-tank trolley, and the like. The first radar is fixed on the first radar mounting bracket, the second radar is fixed on the second radar mounting bracket, the first wave-absorbing heat sink cover is placed in front of the first radar, the second wave-absorbing heat sink cover is placed in front of the second radar, and the first wave-absorbing heat sink cover, the second wave-absorbing heat sink cover, the first radar mounting bracket and the second radar mounting bracket are fixed on an in-tank trolley. According to the invention, the blank in the prior art is filled, the vacuum thermal test device for the satellite-borne double-frequency meteorological radar is established, wireless high-power emission can be directly carried out in the vacuum tank, the correctness of radar load thermal design is verified in advance, a basis is provided for thermal analysis and calculation parameter correction, and the verification accuracy of a satellite thermal test is improved.

Description

Technical Field

[0001] The invention belongs to the field of satellite-borne radars, and in particular, relates to a satellite-borne dual-frequency weather radar vacuum thermal test device and a test method. Background Art

[0002] Spaceborne phased array meteorological radar is an active microwave remote sensing instrument with the characteristics of all-day, all-weather, high-precision, large-range observation, high quantification requirements, and continuous operation throughout its life cycle in orbit. It is currently widely used in weather forecasting, climate prediction, disaster monitoring and other aspects.

[0003] As the core component of the spaceborne phased array weather radar, the T / R component has a large transmission power and works continuously for a long time in orbit. The heat consumption and thermal control design are difficult. It is necessary to carry out radar payload thermal tests on the ground to verify the correctness of the thermal design, provide a basis for verifying and modifying the thermal analysis mathematical model, and provide a basis for setting the test temperature for the satellite thermal vacuum test, thereby improving the accuracy of satellite thermal test verification.

[0004] In ground thermal tests, the T / R components need to be turned on to effectively simulate their thermal characteristics. However, if no measures are taken, the high-power transmission signals of the T / R components will be reflected back by the metal wall of the vacuum tank, thereby blocking or even burning the T / R component receiving channel.

[0005] When conducting thermal tests on the ground, traditional phased array radar satellites with a small number of T / R components usually use the method of connecting the T / R component output to the load to solve the microwave reflection problem of the vacuum tank. The onboard dual-frequency weather radar array is large in size and is in the Ka and Ku bands. If it is connected to the T / R components using an adapter cable, it will cause many problems such as load disassembly and fixation. In addition, since the installation accuracy has a great impact on the performance, it is impossible to retest after disassembly and assembly according to the development process, making it difficult to ensure the performance and accuracy of the payload, which brings unknown risks. Therefore, the onboard weather radar payload thermal test device is an urgent problem to be solved.

[0006] The Chinese patent document with publication number CN107121672A discloses a radar satellite vacuum thermal test method based on a microwave absorbing cover, which can perform microwave payload wireless high-power transmission test in a vacuum tank, effectively avoiding the product status and performance changes of phased array antennas caused by wireless modification, while saving antenna modification time before and after the satellite vacuum thermal test, greatly shortening the development cycle of radar satellites. However, this prior art uses a microwave absorbing cover on a satellite to carry out radar payload thermal tests, and is not suitable for independent thermal tests on onboard dual-frequency radars.

[0007] The Chinese patent document with publication number CN116243259A discloses a new type of microwave absorbing heat sink device suitable for vacuum thermal testing of microwave radar antennas, which can not only meet the requirements of horizontal deployment of antennas, but also meet the requirements of vertical deployment of antennas, providing more options for optimizing test plans. However, this prior art cannot achieve thermal testing of two radars at the same time.

[0008] The Chinese patent document with publication number CN118209936A discloses a thermal vacuum test calibration method for a spaceborne phased array weather radar, which realizes the calibration of the amplitude and phase characteristics of the spaceborne phased array weather radar. However, the prior art does not involve a radar thermal test device and a dual-frequency radar thermal test method.

[0009] The Chinese patent document with publication number CN110104211A discloses a micro-nano satellite multi-component thermal vacuum batch test device, including a guide rail, a heating unit, and a heat insulation board in a vacuum tank heat sink; the heating unit includes an infrared cage, a bracket, and a mounting plate, and the micro-nano satellite multi-component to be tested is arranged on the mounting plate and the geometric envelope of the infrared cage completely covers the components to be tested, the bracket, and the mounting plate. However, this prior art also does not involve a space-borne radar thermal test device and a dual-frequency radar thermal test test method.

[0010] In the open document "Application of Wave-Absorbing Heat Sinks in Vacuum Thermal Tests of Microwave Radar Imaging Satellites" in Volume 34, Issue 5, October 2017, China's core science and technology journal "Spacecraft Environmental Engineering" introduced a new type of external heat flow simulation device - the wave-absorbing heat sink, which has both the functions of wave absorption and external heat flow simulation. At the same time, a set of verification test schemes were designed to verify the effectiveness of the wave-absorbing heat sink in vacuum thermal tests. The device can be extended to microwave radar imaging satellite thermal tests, but the device is not suitable for simultaneous thermal tests of two radar payloads, and does not include radar thermal test methods.

[0011] In addition, in the open document "Development of Low PIM Absorbing Heat Sink for Whole Satellite Microwave Wireless Testing under Thermal Vacuum Environment" in Volume 34, Issue 4, August 2017, the journal introduced a low passive intermodulation (passive intermodulation, PIM) absorbing heat sink developed using silicon carbide absorbing material, and successfully completed the wireless PIM test involving the entire satellite under a thermal vacuum environment. However, the silicon carbide absorbing material is too heavy, difficult to install in the tank, and has safety risks, so it is not suitable for satellite-borne meteorological radar thermal test equipment.

[0012] In addition, no literature related to the vacuum thermal test equipment and test methods of spaceborne meteorological radar was found. Therefore, it is urgent to develop and establish equipment for vacuum thermal testing of spaceborne meteorological radar, summarize a set of thermal test methods, verify the correctness of the thermal design of the radar payload in advance, provide a basis for the correction of thermal analysis calculation parameters, improve the accuracy of satellite thermal test verification, and then promote its application in subsequent vacuum thermal tests of spaceborne meteorological radar payloads. Summary of the invention

[0013] In view of the defects in the prior art, the object of the present invention is to provide a vacuum thermal test device and a test method for a satellite-borne dual-frequency weather radar.

[0014] A spaceborne dual-frequency weather radar vacuum thermal test device according to the present invention comprises: a first radar 1, a second radar 2, a first radar mounting bracket 3, a second radar mounting bracket 4, a first wave-absorbing heat sink cover 5, a second wave-absorbing heat sink cover 6 and an in-tank trolley 7;

[0015] The first radar 1 is fixed on a first radar mounting bracket 3, and the second radar 2 is fixed on a second radar mounting bracket 4; the first wave-absorbing heat sink cover 5 is placed in front of the first radar 1, and the second wave-absorbing heat sink cover 6 is placed in front of the second radar 2;

[0016] The first wave absorbing heat sink cover 5 , the second wave absorbing heat sink cover 6 , the first radar mounting bracket 3 , and the second radar mounting bracket 4 are fixed on a tank trolley 7 .

[0017] Preferably, the first radar 1 and the second radar 2 are phased array radars that transmit continuously at high power throughout their entire life cycle on orbit.

[0018] Preferably, the first wave absorbing heat sink cover 5 and the second wave absorbing heat sink cover 6 are used to absorb the high-power signals emitted by the first radar 1 and the second radar 2 and the external heat flow simulation respectively.

[0019] Preferably, the first radar 1 and the second radar 2 are arranged back to back, and the first wave-absorbing heat sink cover 5 and the second wave-absorbing heat sink cover 6 are wave-absorbing heat sinks independently installed for the first radar 1 and the second radar 2 respectively.

[0020] A vacuum thermal test method for a spaceborne dual-frequency weather radar provided by the present invention comprises the following steps:

[0021] Step 1: According to the requirements of the operating frequency, transmission power, size and external heat flow simulation index of the first radar 1 and the second radar 2, a first wave absorbing heat sink cover 5 and a second wave absorbing heat sink cover 6 that meet the use requirements are manufactured;

[0022] Step 2: Install the first radar 1 and the second radar 2 on the first radar mounting bracket 3 and the second radar mounting bracket 4 respectively, and perform thermal control on the first radar 1 and the second radar 2;

[0023] Step 3: Install the first wave absorbing heat sink cover 5 and the second wave absorbing heat sink cover 6 on the trolley in the tank, 500 mm in front of the first radar 1 and the second radar 2 respectively;

[0024] Step 4: Push the in-tank trolley 7 as a whole into the vacuum tank and fix it on the guide rail of the vacuum tank;

[0025] Step 5: Connect the heating cables, temperature measuring cables and test cables inside and outside the tank;

[0026] Step 6: Before closing the tank, start the first radar 1 and the second radar 2 according to the power-on procedure to conduct product electrical testing, and confirm the status of the satellite-borne dual-frequency radar products participating in the thermal test;

[0027] Step seven, after the electrical test before closing the tank is completed, the first radar 1 and the second radar 2 are shut down according to the power-off procedure, the vacuum tank is closed, vacuumed, liquid nitrogen is passed, and the satellite-borne dual-frequency meteorological radar carries out the test work according to the thermal test and electrical test specifications.

[0028] Preferably, in step 1, the absorbing performance indicators of the first absorbing heat sink cover 5 and the second absorbing heat sink cover 6 are determined by the working bands and transmission powers of the first radar 1 and the second radar 2 , and the sizes are determined by the sizes of the first radar 1 and the second radar 2 .

[0029] Preferably, in the step 1, the external heat flow simulation function of the first wave absorbing heat sink cover 5 and the second wave absorbing heat sink cover 6 is determined by the external heat flow simulation index requirement.

[0030] Preferably, in the step 1, absorbing plates are arranged around the first absorbing heat sink cover 5 and the second absorbing heat sink cover 6 to ensure that there is no signal leakage.

[0031] Preferably, when the first radar 1 and the second radar 2 perform a high-power wireless transmission test in a vacuum tank, the high-power signals transmitted by them are converted into heat energy through the first wave-absorbing heat sink cover 5 and the second wave-absorbing heat sink cover 6 .

[0032] Preferably, the test is performed using the satellite-borne dual-frequency weather radar vacuum thermal test device.

[0033] Compared with the prior art, the present invention has the following beneficial effects:

[0034] 1. The present invention fills the gap in the prior art and establishes a spaceborne dual-frequency weather radar vacuum thermal test device, which can realize the thermal test of two radars at the same time. Among them, the present invention takes into account the problem that the absorbing heat sinks of the two radars are in the same plane, there is mutual influence, and the external heat flow cannot be applied independently, which affects the accuracy of the radar thermal test. For this reason, the two radar thermal test devices in the present invention are installed back to back and the absorbing heat sinks are installed independently to improve the accuracy of the external heat flow application, thereby improving the accuracy of the thermal test.

[0035] 2. The present invention can directly perform high-power wireless transmission in a vacuum tank, verify the correctness of the radar payload thermal design in advance through radar payload thermal tests, provide a basis for correcting thermal analysis calculation parameters, and improve the accuracy of satellite thermal test verification.

[0036] 3. The present invention verifies the correctness of the thermal design of the radar payload in advance, provides a basis for the correction of thermal analysis calculation parameters, and is further promoted and applied to subsequent vacuum thermal tests of satellite-borne meteorological radar payloads. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Other features, objects and advantages of the present invention will become more apparent from the detailed description of non-limiting embodiments made with reference to the following drawings:

[0038] Figure 1 This is a schematic diagram of a vacuum thermal test device for a spaceborne dual-frequency weather radar according to an embodiment of the present invention;

[0039] Figure 2 The present invention is a flowchart of a vacuum thermal test method for a spaceborne dual-frequency weather radar according to an embodiment of the present invention.

[0040] The figure shows:

[0041] A first radar 1; a second radar 2; a first radar mounting bracket 3; a second radar mounting bracket 4; a first wave-absorbing heat sink cover 5; a second wave-absorbing heat sink cover 6; and an in-tank trolley 7. DETAILED DESCRIPTION

[0042] The present invention is described in detail below in conjunction with specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. It should be noted that, for those of ordinary skill in the art, several changes and improvements can also be made without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

[0043] like Figure 1As shown, an embodiment of the present invention provides a satellite-borne dual-frequency meteorological radar vacuum thermal test device, including a first radar 1, a second radar 2, a first radar mounting bracket 3, a second radar mounting bracket 4, a first wave-absorbing heat sink cover 5, a second wave-absorbing heat sink cover 6 and an in-tank trolley 7, wherein the first radar 1 is fixed on the first radar mounting bracket 3, the second radar 2 is fixed on the second radar mounting bracket 4, the first wave-absorbing heat sink cover 5 is placed directly in front of the first radar 1, the second wave-absorbing heat sink cover 6 is placed directly in front of the second radar 2, and the first wave-absorbing heat sink cover 5, the second wave-absorbing heat sink cover 6, the first radar mounting bracket 3, and the second radar mounting bracket 4 are fixed on an in-tank trolley 7.

[0044] The first radar 1 and the second radar 2 are phased array radars that transmit continuously at high power throughout their entire life cycle in orbit.

[0045] The first wave absorbing heat sink cover 5 and the second wave absorbing heat sink cover 6 are used for absorbing the high-power signals emitted by the first radar 1 and the second radar 2 and simulating the external heat flow, respectively.

[0046] like Figure 2 As shown, the embodiment of the present invention also provides a vacuum thermal test method for a spaceborne dual-frequency weather radar, comprising the following steps:

[0047] Step 1: According to the requirements of the operating frequency, transmission power, size and external heat flow simulation index of the first radar 1 and the second radar 2, a first wave absorbing heat sink cover 5 and a second wave absorbing heat sink cover 6 that meet the use requirements are manufactured;

[0048] Step 2: Install the first radar 1 and the second radar 2 on the first radar mounting bracket 3 and the second radar mounting bracket 4 respectively, and perform thermal control on the first radar 1 and the second radar 2;

[0049] Step 3: Install the first wave absorbing heat sink cover 5 and the second wave absorbing heat sink cover 6 on the trolley in the tank, 500 mm in front of the first radar 1 and the second radar 2 respectively;

[0050] Step 4: Push the in-tank trolley 7 as a whole into the vacuum tank and fix it on the guide rail of the vacuum tank;

[0051] Step 5: Connect the heating cables, temperature measuring cables and test cables inside and outside the tank;

[0052] Step 6: Before closing the tank, start the first radar 1 and the second radar 2 according to the power-on procedure to conduct product electrical testing, and confirm the status of the satellite-borne dual-frequency radar products participating in the thermal test;

[0053] Step seven, after the electrical test before closing the tank is completed, the first radar 1 and the second radar 2 are shut down according to the power-off procedure, the vacuum tank is closed, vacuumed, liquid nitrogen is passed, and the satellite-borne dual-frequency meteorological radar carries out the test work according to the thermal test and electrical test specifications.

[0054] The wave absorbing performance indicators of the first wave absorbing heat sink cover 5 and the second wave absorbing heat sink cover 6 are respectively determined by the working bands and transmission powers of the first radar 1 and the second radar 2 , and the sizes are respectively determined by the sizes of the first radar 1 and the second radar 2 .

[0055] The external heat flow simulation function of the first wave absorbing heat sink cover 5 and the second wave absorbing heat sink cover 6 is determined by the external heat flow simulation index requirements.

[0056] Wave absorbing plates are arranged around the first wave absorbing heat sink cover 5 and the second wave absorbing heat sink cover 6 to ensure that there is no signal leakage.

[0057] When the first radar 1 and the second radar 2 perform a high-power wireless transmission test in the vacuum tank, the high-power signals transmitted by them are converted into heat energy through the first wave-absorbing heat sink cover 5 and the second wave-absorbing heat sink cover 6 .

[0058] The present invention will be described in more detail below.

[0059] The first radar 1 of the satellite-borne dual-frequency weather radar has an operating frequency of 13.35±0.01GHz, a maximum transmission power of 750W, and an overall geometric size of 2308mm (X direction)*2469mm (Y direction)*468mm (Z direction);

[0060] The operating frequency of the second radar 2 of the satellite-borne dual-frequency meteorological radar is 35.55±0.01GHz, the maximum transmission power is 350W, and the geometric dimensions are 1100mm (X direction)*2040mm (Y direction)*750mm (Z direction);

[0061] According to the maximum power transmitted by the radar, it can be determined that the absorbing performance of the heat absorbing cover is that the reflectivity of the electromagnetic waves emitted by the dual-frequency radar is not higher than -25dB. According to the geometric dimensions of the radar shape, the envelope size of the heat absorbing cover is determined to be consistent with the size of the radar +Z surface, and the allowable size deviation is within 100mm.

[0062] The external heat flux simulation index requirements of the absorbing heat sink cover are: the deviation between the average value of the heat flux simulation in the heating area and the required value is ±5%, the heat flux density non-uniformity is ±5%, the external heat flux simulation range is 100W / ㎡~300W / ㎡, and there must be a 20% heating design margin.

[0063] According to the requirements of the satellite-borne dual-frequency meteorological radar for the wave absorbing performance, size and external heat flow simulation of the wave absorbing heat sink cover, a first wave absorbing heat sink cover 5 and a second wave absorbing heat sink cover 6 that meet the requirements are manufactured.

[0064] The first radar 1 and the second radar 2 are respectively mounted on the first radar mounting bracket 3 and the second radar mounting bracket 4, and the first radar 1 and the second radar 2 are covered with multiple layers and other thermal control measures. The prepared first absorbing heat sink cover 5 and the second absorbing heat sink cover 6 are mounted on the tank trolley 7, and are 500 mm away from the front of the first radar 1 and the second radar 2, respectively. Figure 1 shown.

[0065] Push the tank trolley 7 as a whole into the vacuum tank and fix it on the guide rail of the vacuum tank, connect the heating cables, temperature measuring cables and test cables inside and outside the tank, start the first radar 1 and the second radar 2 according to the power-on procedure before closing the tank to perform product electrical testing, and confirm the status of the satellite-borne dual-frequency radar products participating in the thermal test.

[0066] After the electrical test before closing the tank is completed, the first radar 1 and the second radar 2 are shut down according to the power-off procedure, the vacuum tank is closed, vacuumed, and liquid nitrogen is passed. The satellite-borne dual-frequency meteorological radar carries out the test work according to the thermal test and electrical test specifications.

[0067] In summary, the present invention fills the gap in the prior art and establishes a satellite-borne dual-frequency meteorological radar vacuum thermal test device, which can directly perform wireless high-power transmission in a vacuum tank, verify the correctness of the radar payload thermal design in advance through the radar payload thermal test, provide a basis for the correction of thermal analysis calculation parameters, and improve the accuracy of satellite thermal test verification.

[0068] The above describes the specific embodiments of the present invention. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art can make various changes or modifications within the scope of the claims, which does not affect the essence of the present invention. In the absence of conflict, the embodiments of the present application and the features in the embodiments can be combined with each other arbitrarily.

Claims

1. A spaceborne dual-frequency weather radar vacuum thermal test device, characterized in that: include: A first radar (1), a second radar (2), a first radar mounting bracket (3), a second radar mounting bracket (4), a first wave absorbing heat sink cover (5), a second wave absorbing heat sink cover (6), and an in-tank trolley (7); The first radar (1) is fixed on a first radar mounting bracket (3), and the second radar (2) is fixed on a second radar mounting bracket (4); the first wave-absorbing heat sink cover (5) is placed directly in front of the first radar (1), and the second wave-absorbing heat sink cover (6) is placed directly in front of the second radar (2); The first wave-absorbing heat sink cover (5), the second wave-absorbing heat sink cover (6), the first radar mounting bracket (3), and the second radar mounting bracket (4) are fixed on a tank trolley (7).

2. The spaceborne dual-frequency weather radar vacuum thermal test device according to claim 1 is characterized in that: The first radar (1) and the second radar (2) are phased array radars that transmit continuously at high power throughout their entire life cycle on orbit.

3. The spaceborne dual-frequency weather radar vacuum thermal test device according to claim 1, characterized in that: The first wave-absorbing heat sink cover (5) and the second wave-absorbing heat sink cover (6) are used to absorb the high-power signals emitted by the first radar (1) and the second radar (2) and external heat flow simulation respectively.

4. The spaceborne dual-frequency weather radar vacuum thermal test device according to claim 1, characterized in that: The first radar (1) and the second radar (2) are arranged opposite to each other, and the first wave-absorbing heat sink cover (5) and the second wave-absorbing heat sink cover (6) are wave-absorbing heat sinks independently installed for the first radar (1) and the second radar (2), respectively.

5. A vacuum thermal test method for a spaceborne dual-frequency weather radar, characterized in that: The following steps are involved: Step 1: According to the requirements of the operating frequency, transmission power, size and external heat flow simulation index of the first radar (1) and the second radar (2), a first wave absorbing heat sink cover (5) and a second wave absorbing heat sink cover (6) that meet the use requirements are manufactured; Step 2: installing the first radar (1) and the second radar (2) on the first radar mounting bracket (3) and the second radar mounting bracket (4) respectively, and performing thermal control measures on the first radar (1) and the second radar (2); Step 3, installing the first wave absorbing heat sink cover (5) and the second wave absorbing heat sink cover (6) on the in-tank trolley (7), respectively at a distance in front of the first radar (1) and the second radar (2); Step 4: Push the in-tank trolley (7) as a whole into the vacuum tank and fix it on the guide rail of the vacuum tank; Step 5: Connect the heating cables inside and outside the tank, the temperature measuring cables and the test cables; Step 6: Before closing the tank, the first radar (1) and the second radar (2) are powered on according to the power-on procedure to conduct product electrical testing, and the status of the satellite-borne dual-frequency radar products participating in the thermal test is confirmed; Step 7: After the electrical test before closing the tank is completed, the first radar (1) and the second radar (2) are shut down according to the power-off procedure, the vacuum tank is closed, vacuumed, and liquid nitrogen is passed. The satellite-borne dual-frequency meteorological radar carries out the test work according to the thermal test and electrical test specifications.

6. The spaceborne dual-frequency weather radar vacuum thermal test method according to claim 5, characterized in that: In the step 1, the wave absorbing performance index of the first wave absorbing heat sink cover (5) and the second wave absorbing heat sink cover (6) is determined by the working band and transmission power of the first radar (1) and the second radar (2), and the size is determined by the size of the first radar (1) and the second radar (2).

7. The vacuum thermal test method for a spaceborne dual-frequency weather radar according to claim 5, characterized in that: In the step 1, the external heat flow simulation function of the first wave absorbing heat sink cover (5) and the second wave absorbing heat sink cover (6) is determined by the external heat flow simulation index requirement.

8. The vacuum thermal test method for a spaceborne dual-frequency weather radar according to claim 5, characterized in that: In the step 1, wave absorbing plates are arranged around the first wave absorbing heat sink cover (5) and the second wave absorbing heat sink cover (6) to ensure that there is no signal leakage.

9. The spaceborne dual-frequency weather radar vacuum thermal test method according to claim 5, characterized in that: When the first radar (1) and the second radar (2) are subjected to a high-power wireless transmission test in a vacuum tank, the high-power signals transmitted by them are converted into heat energy through the first wave-absorbing heat sink cover (5) and the second wave-absorbing heat sink cover (6).

10. The spaceborne dual-frequency weather radar vacuum thermal test method according to claim 5, characterized in that: The test is carried out using the spaceborne dual-frequency weather radar vacuum thermal test device described in any one of claims 1 to 4.

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