Switching system and method for satellite differential signal waveform measurement

Abstract

The invention provides a switching system and method for satellite differential signal waveform measurement, and the system comprises a differential signal matching and gating unit which is used for carrying out the measurement path selection of a differential signal; the oscilloscope and the probe are used for measuring differential signals; the main control unit is used for sending a measurement instruction and controlling the differential signal matching and gating unit, the oscilloscope and the probe; the oscilloscope and the probe interact with the main control unit in a network mode, receive a measurement instruction of the main control unit and send a measurement result to the main control unit. Intensive design is adopted, the problems of various systems and disordered wiring in the satellite differential signal interface waveform measurement process are solved, one-time parallel access and serial measurement of multiple paths of differential signals are achieved, and the safety and efficiency of the measurement process are greatly improved.

Description

Technical Field

[0001] This invention relates to the field of spacecraft signal measurement technology, and more specifically, to a switching system and method for measuring satellite differential signal waveforms. Background Technology

[0002] A satellite is a complex information system, equipped with various differential communication interfaces such as TLK2711, LVDS, RS-422, and 1553b to meet different data transmission requirements. The reliability of these communication interfaces directly determines the realization of satellite functions, making output characteristic testing a crucial part of satellite testing. During the unit acceptance and satellite installation testing phases, the output waveforms of various electrical interfaces must be tested to ensure that the various indicators of the signal interfaces meet the requirements.

[0003] Satellite connectors typically contain multiple pairs of differential signals. Under current technological conditions, testing signal output waveforms is difficult due to limited testing resources and inconvenient wiring connections. This often requires multiple satellite power cycles and reconnection / reconnection, resulting in low testing efficiency and insufficient safety. Furthermore, the automation level of testing operations and data recording is low, heavily reliant on manual operation, which increases the risk of human error. Additionally, the lack of standardized test report generation and the absence of quantitative basis for comparing the quality of multiple signals further affect the accuracy and comparability of test results.

[0004] The patent application with application number CN112834965 provides an automatic testing device for satellite electrical interfaces, including: a programmable junction box, including at least one connector, at least one multiplexer, at least one bus and at least one interface under test. The signal of the device under test is provided to the data acquisition module in sequence through the connector, the multiplexer, the bus and the interface under test. The control and analysis module provides remote control commands to the multiplexer according to the user's test case requirements to control the on / off state of the multiplexer's path.

[0005] However, the aforementioned patents can only test voltage and current signals such as power supply voltage, power, and surge of a single unit, and cannot achieve impedance matching and serial automated testing of multiple channels and multiple types of differential signals.

[0006] Patent application number CN106788787 provides a method for rapid testing and analysis of spaceborne high-speed LVDS parallel signals, applicable to parallel LVDS interfaces with various transmission rates, solving the technical problem that high-speed LVDS parallel interfaces cannot be tested and analyzed quickly and accurately.

[0007] However, the aforementioned patent still requires repeated wiring to measure multiple pairs of differential signals in a single connector, and does not cover other differential signal types commonly used by satellites. Summary of the Invention

[0008] In view of the deficiencies in the prior art, the purpose of this invention is to provide a switching system and method for measuring satellite differential signal waveforms.

[0009] A switching system for satellite differential signal waveform measurement according to the present invention includes: The differential signal matching and gating unit is used to select the measurement path for the differential signal; Oscilloscope and probes for measuring differential signals; The main control unit is used to send measurement commands and control the differential signal matching and gating unit, oscilloscope, and probe; The oscilloscope and probe interact with the main control unit via a network, receiving measurement commands from the main control unit and sending measurement results to the main control unit.

[0010] Preferably, the differential signal matching and gating unit includes: High-speed differential signal matching and gating unit, used to realize the selection of measurement path and impedance matching after no less than 8 pairs of TLK2711 differential signals are connected in parallel; The medium- and low-speed differential signal and single-ended signal matching and gating unit is used to realize the selection of measurement paths and impedance matching for no less than 37 pairs of medium- and low-speed differential signals or the selection of measurement paths for 74 single-ended signals.

[0011] Preferably, the main control unit includes: An automated control module is used to control the gating of differential signals and the operation of the oscilloscope. The data analysis and summary module is used to record and analyze the measurement results of differential signals and generate reports.

[0012] Preferably, the oscilloscope includes an eye diagram measurement module, and the probe is a differential probe without built-in terminating resistors when performing differential signal measurements.

[0013] Preferably, the high-speed differential signal matching and gating unit includes: The first-level switch matrix module consists of four 4-to-1 switch matrices, which are connected to 16 differential signals to perform the first round of signal selection. After the selection is completed, there are 2 positive differential signals and 2 negative differential signals remaining. The secondary switch matrix module consists of two 2-to-1 switch matrices for the second round of signal selection. After the selection is completed, the remaining one differential positive signal line and one differential negative signal line are connected to the measurement interface. The high-speed impedance matching module consists of a three-to-one switch matrix, multi-position matching resistors, and a combiner. The three-to-one switch matrix controls the selection of matching resistors for high-speed differential signals.

[0014] Preferably, the connections between devices in the high-speed differential signal matching and gating unit all use coaxial cables with SMA high-frequency interfaces, and both the RF devices and cables support the DC~4GHz frequency band.

[0015] Preferably, the medium-low speed differential signal and single-ended signal matching and gating unit includes: The first relay module consists of 74 programmable relays. One end of the relay path is connected to the 74 pins of the signal input connector one by one, and the other end is connected to each other to select the positive line of the differential signal. The second relay module consists of 74 programmable relays. One end of the relay path is connected to the 74 pins of the signal input connector one by one, and the other end is connected to each other to select the negative line of the differential signal. The medium-low speed impedance matching module consists of a third relay module and a multi-position matching resistor. The selection of the multi-position matching resistor for medium-low speed differential signals is controlled by the third relay module.

[0016] Preferably, the relays selected for the first relay module, the second relay module, and the third relay module are all electromagnetic relays, supporting the DC~4GHz frequency band, and are installed on three PCBs according to the module.

[0017] Preferably, the matching resistors in the high-speed impedance matching module are divided into three levels, while those in the medium- and low-speed impedance matching module are divided into five levels.

[0018] A switching method for satellite differential signal waveform measurement according to the present invention includes: Step S1: Connect the multi-channel differential signal output from the satellite to the input interface of the adapter system via an adapter cable, and connect the oscilloscope probe to the output interface of the adapter system; Step S2: The main control unit controls the differential signal matching and gating unit to perform signal gating and impedance matching according to the preset test file; Step S3: Control the satellite or onboard unit to output the differential signal to be measured; Step S4: The main control unit sends a measurement command to the oscilloscope based on the preset test file. The oscilloscope and probe perform waveform measurement on the selected differential signal and obtain the measurement results. Step S5: The main control unit receives the measurement results returned by the oscilloscope, records and analyzes them, and then generates a test summary report.

[0019] Compared with the prior art, the present invention has the following beneficial effects: 1. This invention has strong versatility and high integration, and is compatible with various types of differential signal waveform measurements commonly used in satellites, such as TLK2711, LVDS, RS-422, and 1553b. The designed high-speed differential signal matching and gating unit, medium- and low-speed differential signal and single-ended signal matching and gating unit, and main control unit can be integrated into a 4U standard chassis, which greatly improves the convenience of signal conversion in the waveform measurement process.

[0020] 2. The present invention has high security and high degree of automation. It can simultaneously access up to 8 pairs of high-speed differential signals and 37 pairs of medium and low-speed differential signals, and measure all differential signals in one or more satellite connectors at one time, greatly reducing the number of cable plugging and unplugging. All measurement channel selection and terminal matching load selection are executed automatically by program control, and test result reports can be automatically generated.

[0021] 3. The present invention has strong scalability. When the system size or the number of oscilloscope channels is expanded, more differential signals can be tested in parallel, further improving the testing efficiency. Attached Figure Description

[0022] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings: Figure 1 This is a schematic diagram showing the composition and connection of the satellite differential signal waveform measurement and switching system and method of the present invention.

[0023] Figure 2 This is a schematic diagram showing the composition and connection of the high-speed differential signal matching and gating unit described in this invention.

[0024] Figure 3 This is a schematic diagram showing the composition and connection of the low-speed differential signal and single-ended signal matching and gating unit described in this invention.

[0025] Figure 4 This is a schematic diagram of the automated testing process for satellite differential signal waveforms according to an embodiment of the present invention. Detailed Implementation

[0026] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make several changes and improvements without departing from the concept of the present invention. These all fall within the protection scope of the present invention.

[0027] like Figure 1 As shown, a switching system for satellite differential signal waveform measurement includes: The differential signal matching and gating unit is used to select the measurement path for the differential signal; Oscilloscope and probes for measuring differential signals; The main control unit is used to send measurement commands and control the differential signal matching and gating unit, oscilloscope, and probe; The oscilloscope and probe interact with the main control unit via a network, receiving measurement commands from the main control unit and sending measurement results to the main control unit.

[0028] The differential signal matching and gating unit includes: High-speed differential signal matching and gating unit, used to realize the selection of measurement path and impedance matching after no less than 8 pairs of TLK2711 differential signals are connected in parallel; Medium and low speed differential signal and single-ended signal matching and gating unit, used to realize the selection of measurement path and impedance matching of no less than 37 pairs of medium and low speed differential signals such as LVDS, RS-422, 1553b or the selection of measurement path for 74 single-ended signals; The main control unit can read the measurement parameters in the test file and generate automated test steps. The included automated control module controls the signal gating and oscilloscope operation according to the test steps, and the included data analysis and summary module records and analyzes the signal measurement results and generates a report. The analysis indicators include differential amplitude, common-mode voltage, rise / fall time, and eye diagram parameters such as eye height, eye width, and eye crossover ratio. The oscilloscope and probe are used for signal measurement and interact with the main control unit via a network. The oscilloscope receives measurement commands from the main control unit and sends measurement results to the main control unit. The oscilloscope should include an eye diagram measurement module. When performing differential signal measurement, the probe is a differential probe without built-in terminating resistors.

[0029] like Figure 2 As shown, the high-speed differential signal matching and gating unit includes: A primary switch matrix module, which consists of four 4-to-1 switch matrices, is connected to 16 differential signals to perform the first round of signal selection. After the selection is completed, there are 2 positive differential signals and 2 negative differential signals remaining. A two-stage switch matrix module, consisting of two 2-to-1 switch matrices, performs a second round of signal selection. After selection, the remaining one differential positive signal line and one differential negative signal line are connected to the measurement interface. A high-speed impedance matching module, comprising a three-to-one switch matrix, multi-position matching resistors, and a combiner, wherein the three-to-one switch matrix controls the selection of matching resistors for high-speed differential signals.

[0030] In the high-speed differential signal matching and gating unit, the connections between devices all use coaxial cables with SMA high-frequency interfaces. Both the RF devices and cables support the DC~4GHz frequency band.

[0031] The high-speed impedance matching module has three matching resistors: a 50Ω fixed resistor, a 1mΩ~200Ω adjustable programmable resistor, and a 1MΩ fixed resistor. The 50Ω fixed resistor serves as the terminating matching load for the TLK2711 signal, the 1mΩ~200Ω adjustable programmable resistor is used to adapt to the terminating matching load of other differential signals that may need to be tested, and the 1MΩ fixed resistor can be connected for single-ended signal testing or as a protection state.

[0032] The signal gating and impedance matching functions in the high-speed differential signal matching and gating unit are both implemented by a switching matrix.

[0033] like Figure 3 As shown, the low-to-medium speed differential signal and single-ended signal matching and gating unit includes: The first relay module consists of 74 programmable relays. One end of the relay path is connected to the 74 pins of the signal input connector one by one, and the other end is connected to each other to perform differential signal positive line selection. The second relay module consists of 74 programmable relays. One end of the relay path is connected to the 74 pins of the signal input connector, and the other end is connected to each other to select the negative line of the differential signal. A medium-low speed impedance matching module, which consists of a third relay module and a multi-position matching resistor, is controlled by the third relay module to achieve the selection of the multi-position matching resistor for medium-low speed differential signals.

[0034] The relays used in the first, second, and third relay modules are all electromagnetic relays, supporting the DC~4GHz frequency band, and are installed on three PCBs according to the module.

[0035] The low-to-medium speed impedance matching module has five matching resistor options: 78Ω fixed resistor, 100Ω fixed resistor, 120Ω fixed resistor, 1mΩ~200Ω adjustable programmable resistor, and 1MΩ fixed resistor. The 78Ω fixed resistor serves as the terminating matching load for 1553b signals, the 100Ω fixed resistor for LVDS signals, the 120Ω fixed resistor for RS-422 signals, the 1mΩ~200Ω adjustable programmable resistor for terminating matching loads of other differential signals that may require testing, and the 1MΩ fixed resistor allows for single-ended signal testing or protection mode.

[0036] like Figure 4 As shown, a switching method for satellite differential signal waveform measurement includes: Step S1: Connect the multi-channel differential signal output from the satellite to the input interface of the adapter system via an adapter cable, and connect the oscilloscope probe to the output interface of the adapter system; Step S2: The main control unit controls the differential signal matching and gating unit to perform signal gating and impedance matching according to the preset test file; Step S3: Control the satellite or onboard unit to output the differential signal to be measured; Step S4: The main control unit sends a measurement command to the oscilloscope based on the preset test file. The oscilloscope and probe perform waveform measurement on the selected differential signal and obtain the measurement results. Step S5: The main control unit receives the measurement results returned by the oscilloscope, records and analyzes them, and then generates a test summary report.

[0037] Example 1 In this embodiment, the high-speed differential signal matching and gating unit, the medium- and low-speed differential signal and single-ended signal matching and gating unit, and the main control unit are integrated into a 4U standard chassis. The chassis panel integrates 16 SMA coaxial cable connectors for connecting high-speed differential signals from the satellite; and a J14-74ZJL low-frequency connector for connecting medium- and low-speed differential signals from the satellite. Output interfaces include SMA connector measurement interfaces P1 and N1 for outputting high-speed differential signals from the satellite to an oscilloscope probe; and banana-shaped connector measurement interfaces P2 and N2 for outputting medium- and low-speed differential signals from the satellite to an oscilloscope probe.

[0038] In this embodiment, the main control unit consists of an industrial control computer CPU, motherboard, memory, hard disk, etc., and controls the matrix switch and relay through the PCI interface of the motherboard. The main control unit's host computer controls the signal gating and oscilloscope operation through the automation control module, and the operation data analysis and summary module records and analyzes the signal measurement results and generates a report. The analysis indicators include differential amplitude, common-mode voltage, rise / fall time, and eye diagram parameters such as eye height, eye width, and eye crossover ratio. In this embodiment, the oscilloscope and probe are used for signal measurement and interact with the main control unit via a network. The oscilloscope receives measurement commands from the main control unit and sends the measurement results to the main control unit. The oscilloscope should include an eye diagram measurement module, and the probe is a differential probe without built-in terminating resistors when performing differential signal measurement.

[0039] In this embodiment, the high-speed differential signal matching and gating unit is as follows: Figure 2As shown, by accessing 16 high-speed differential signals, the measurement path selection and impedance matching of at least 8 pairs of TLK2711 differential signals after parallel access are achieved. The specific steps are as follows: Step 1. The programmable controller operates the first-level switch matrix module to perform the first round of signal selection. The first-level switch matrix module consists of four 4-to-1 switch matrices, which are connected to 16 high-speed differential signals. 4-to-1 switch matrices K1 and K2 are connected to 8 differential signal positive lines (P), and 4-to-1 switch matrices K3 and K4 are connected to 8 differential signal negative lines (N). After the first round of signal selection according to the required measurement node, the remaining 2 differential signal positive lines (P) and 2 differential signal negative lines (N) enter the second-level switch matrix module. Step 2. The programmable control module of the secondary switch matrix performs the second round of signal selection. The secondary switch matrix module consists of two 2-to-1 switch matrices, which are connected to the four differential signals after the first round of signal selection. The 2-to-1 switch matrix K5 is connected to two differential signal positive lines (P), and the 2-to-1 switch matrix K6 is connected to two differential signal negative lines (N) for the second round of signal selection. After the second round of signal selection according to the required measurement node, the remaining one differential signal positive line and one differential signal negative line are connected to the measurement interfaces P1 and N1. Step 3. Use programmable control to select the matching impedance of the high-speed impedance matching module. The high-speed impedance matching module consists of a three-to-one switch matrix, multiple matching resistors, and a combiner. The three-to-one switch matrix K7 controls the selection of the matching resistor for high-speed differential signals. For the TLK2711 signal, control the three-to-one switch matrix K7 to select the 50Ω resistance range so that the matching impedance connected to the measurement path is 50 ohms.

[0040] In the high-speed differential signal matching and gating unit, the connections between devices all use coaxial cables with SMA high-frequency interfaces. Both the RF devices and cables support the DC~4GHz frequency band. The high-speed impedance matching module has three matching resistors: a 50Ω fixed resistor, a 1mΩ~200Ω adjustable programmable resistor, and a 1MΩ fixed resistor. The 50Ω fixed resistor serves as the terminating matching load for the TLK2711 signal, the 1mΩ~200Ω adjustable programmable resistor is used to adapt to the terminating matching load of other differential signals that may need to be tested, and the 1MΩ fixed resistor can be connected for single-ended signal testing or as a protection state. The signal gating and impedance matching functions in the high-speed differential signal matching and gating unit are both implemented by a switching matrix.

[0041] In this embodiment, the medium- and low-speed differential signal and single-ended signal matching and gating unit is as follows: Figure 3As shown, by accessing 74 medium-low speed differential signals or single-ended signals, the measurement path selection and termination impedance matching of no less than 37 pairs of medium-low speed differential signals such as LVDS, RS-422, and 1553b, or the measurement path selection of 74 single-ended signals, can be achieved. The specific steps are as follows: Step 1. The first relay module is controlled by a programmable controller to select the positive signal line. The first relay module consists of 74 programmable relays. One end of the relay path is connected to one of the 74 pins of the signal input connector, and the other end is interconnected. Differential signal positive line selection is performed according to the required measurement node. Step 2. Use programmable control to select the negative signal line of the second relay module. The second relay module consists of 74 programmable relays. One end of the relay path is connected to each of the 74 pins of the signal input connector, and the other end is interconnected. Select the negative differential signal line according to the required measurement node. Step 3. Programmable control of the low-speed impedance matching module to select the matching impedance. The low-speed impedance matching module consists of a third relay module and multi-position matching resistors. The third relay module controls the selection of multi-position matching resistors for low-speed differential signals. During the measurement process, different matching impedances are selected according to different signal types.

[0042] In this embodiment, the relays selected for the first relay module, the second relay module, and the third relay module support the DC~4GHz signal frequency band and are installed on three PCBs according to the module.

[0043] In this embodiment, the matching resistors in the low-to-medium speed impedance matching module are divided into five levels: 78Ω fixed resistor, 100Ω fixed resistor, 120Ω fixed resistor, 1mΩ~200Ω adjustable programmable resistor, and 1MΩ fixed resistor. The 78Ω fixed resistor serves as the terminating matching load for the 1553b signal, the 100Ω fixed resistor for the LVDS signal, the 120Ω fixed resistor for the RS-422 signal, and the 1mΩ~200Ω adjustable programmable resistor is used to adapt to the terminating matching loads of other differential signals that may need to be tested. Connecting the 1MΩ fixed resistor allows for single-ended signal testing or protection mode.

[0044] Example 2: The following is combined Figure 4 Taking the measurement scenarios of high-speed differential signals and medium-to-low-speed differential signals as examples, the implementation process of this system is illustrated: Step 1. Satellite-to-ground cable connection: Connect the satellite differential signal transmission cable to the input interface of the adapter system via an adapter cable, and connect the oscilloscope probe to the output interface of the adapter system; Step 2. Read measurement parameters and generate automated test steps: Power on the adapter system and oscilloscope, operate the automated control module in the host computer of the main control unit to read the test file (the test file contains cable connection information of the signal under test, oscilloscope parameter setting requirements, and data recording and interpretation requirements, etc.), program the status of the matrix switch module and relay module, and program the oscilloscope measurement parameters.

[0045] Reference Figure 2 For example, if the first group of signals to be measured in a high-speed differential signal analyzer is a TLK2711 signal, with points P1 and N1, then the four-to-one matrix switch K1 selects point P1, and the four-to-one matrix switch K3 selects point N1; the two-to-one matrix switch K5 selects the K1 path, and the two-to-one matrix switch K6 selects the K3 path; the three-to-one matrix switch K7 selects the 50Ω fixed resistance range. At this point, the measurement channels for P1 and N1 are selected, and the terminal matching impedance is 50Ω, allowing for TLK2711 signal waveform measurement. Similarly, other signal points to be measured are read sequentially, generating corresponding automated execution steps. Reference Figure 3 If the first group of signals to be measured in a low-to-medium speed differential signal test is an LVDS signal, with points 1 and 2, then relay K1-1 in programmable relay module 1 is turned on, and all others are turned off; relay K2-2 in programmable relay module 2 is turned on, and all others are turned off; and relay K3-2 in programmable relay module 3 is turned on, and all others are turned off. At this point, the measurement channels for points 1 and 2 are selected, and the terminal matching impedance is 100Ω, allowing for LVDS signal waveform measurement. Similarly, other signal points to be measured are read sequentially to generate corresponding automated execution steps. Step 3. Satellite output signal: Control the onboard unit to power on, set the status, and output differential signal; Step 4. Measurement and Data Recording: The main control unit transmits SCPI commands through the network port according to the test document, sets the oscilloscope measurement parameters, acquires the measurement images and related parameters, and writes them into the test summary report; Step 5. Repeat steps 2 to 4 to complete all test items specified in the document and generate a test summary report.

[0046] This invention adopts a streamlined design, which solves the problems of numerous systems and messy wiring in the process of satellite differential signal interface waveform measurement. It realizes the parallel access and serial measurement of multiple differential signals at one time, which greatly improves the safety and efficiency of the measurement process.

[0047] This invention employs additional electromagnetic compatibility and reliability designs: the power supply of the chassis uses an EMI filter design, anti-interference ferrite beads are added, and grounding design, wiring and connection design of the electronic and electrical system, and electromagnetic compatibility design of the multilayer printed circuit board are carried out to maximize the safety and reliability of the design and meet the usage requirements of high safety testing.

[0048] Those skilled in the art will understand that, besides implementing the system and its various devices, modules, and units provided by this invention in the form of purely computer-readable program code, the same functions can be achieved entirely through logical programming of the method steps, making the system and its various devices, modules, and units of this invention function in the form of logic gates, switches, application-specific integrated circuits, programmable logic controllers, and embedded microcontrollers. Therefore, the system and its various devices, modules, and units provided by this invention can be considered as a hardware component, and the devices, modules, and units included therein for implementing various functions can also be considered as structures within the hardware component; alternatively, the devices, modules, and units for implementing various functions can be considered as both software modules implementing the method and structures within the hardware component.

[0049] Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. Unless otherwise specified, the embodiments and features described in this application can be arbitrarily combined with each other.

Claims

1. A switching system for measuring satellite differential signal waveforms, characterized in that, include: The differential signal matching and gating unit is used to select the measurement path for the differential signal; Oscilloscope and probes for measuring differential signals; The main control unit is used to send measurement commands and control the differential signal matching and gating unit, oscilloscope, and probe; The oscilloscope and probe interact with the main control unit via a network, receiving measurement commands from the main control unit and sending measurement results to the main control unit.

2. The switching system for satellite differential signal waveform measurement according to claim 1, characterized in that, The differential signal matching and gating unit includes: High-speed differential signal matching and gating unit, used to realize the selection of measurement path and impedance matching after no less than 8 pairs of TLK2711 differential signals are connected in parallel; The medium- and low-speed differential signal and single-ended signal matching and gating unit is used to realize the selection of measurement paths and impedance matching for no less than 37 pairs of medium- and low-speed differential signals or the selection of measurement paths for 74 single-ended signals.

3. The switching system for satellite differential signal waveform measurement according to claim 1, characterized in that, The main control unit includes: An automated control module is used to control the gating of differential signals and the operation of the oscilloscope. The data analysis and summary module is used to record and analyze the measurement results of differential signals and generate reports.

4. The switching system for satellite differential signal waveform measurement according to claim 1, characterized in that, The oscilloscope includes an eye diagram measurement module, and the probe uses a differential probe without built-in terminating resistors when performing differential signal measurements.

5. The switching system for satellite differential signal waveform measurement according to claim 2, characterized in that, The high-speed differential signal matching and gating unit includes: The first-level switch matrix module consists of four 4-to-1 switch matrices, which are connected to 16 differential signals to perform the first round of signal selection. After the selection is completed, there are 2 positive differential signals and 2 negative differential signals remaining. The secondary switch matrix module consists of two 2-to-1 switch matrices for the second round of signal selection. After the selection is completed, the remaining one differential positive signal line and one differential negative signal line are connected to the measurement interface. The high-speed impedance matching module consists of a three-to-one switch matrix, multi-position matching resistors, and a combiner. The three-to-one switch matrix controls the selection of matching resistors for high-speed differential signals.

6. The switching system for satellite differential signal waveform measurement according to claim 2, characterized in that, In the high-speed differential signal matching and gating unit, coaxial cables are used for connections between devices, and the interface is an SMA high-frequency interface. Both the RF devices and cables support the DC~4GHz frequency band.

7. The switching system for satellite differential signal waveform measurement according to claim 2, characterized in that, The low-to-medium speed differential signal and single-ended signal matching and gating unit includes: The first relay module consists of 74 programmable relays. One end of the relay path is connected to the 74 pins of the signal input connector one by one, and the other end is connected to each other to select the positive line of the differential signal. The second relay module consists of 74 programmable relays. One end of the relay path is connected to the 74 pins of the signal input connector one by one, and the other end is connected to each other to select the negative line of the differential signal. The medium-low speed impedance matching module consists of a third relay module and a multi-position matching resistor. The selection of the multi-position matching resistor for medium-low speed differential signals is controlled by the third relay module.

8. The switching system for satellite differential signal waveform measurement according to claim 7, characterized in that, The relays used in the first, second, and third relay modules are all electromagnetic relays, supporting the DC~4GHz frequency band, and are installed on three PCBs according to the module.

9. The switching system for satellite differential signal waveform measurement according to claim 2, characterized in that, In high-speed impedance matching modules, the matching resistors are divided into three levels, while in medium- and low-speed impedance matching modules, the matching resistors are divided into five levels.

10. A switching method for satellite differential signal waveform measurement, employing the switching system for satellite differential signal waveform measurement as described in any one of claims 1-9, characterized in that, include: Step S1: Connect the multi-channel differential signal output from the satellite to the input interface of the adapter system via an adapter cable, and connect the oscilloscope probe to the output interface of the adapter system; Step S2: The main control unit controls the differential signal matching and gating unit to perform signal gating and impedance matching according to the preset test file; Step S3: Control the satellite or onboard unit to output the differential signal to be measured; Step S4: The main control unit sends a measurement command to the oscilloscope based on the preset test file. The oscilloscope and probe perform waveform measurement on the selected differential signal and obtain the measurement results. Step S5: The main control unit receives the measurement results returned by the oscilloscope, records and analyzes them, and then generates a test summary report.

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