With the rapid development of science and technology, especially electronic technology, communication equipment is becoming increasingly powerful and diverse, placing higher demands on its maintenance and testing. Traditional maintenance of communication equipment primarily relies on discrete testing instruments. However, achieving maintenance and testing for multiple communication devices often requires numerous separate, dedicated testing and measurement instruments, resulting in low efficiency, low test coverage, and low fault isolation rates. Adapting to the development trends of communication equipment and incorporating new technologies and advancements in the field of testing and diagnostics, developing a communication equipment testing and diagnostic system to meet the system-level and circuit board-level testing and fault diagnosis needs of various communication devices, improving test coverage, fault diagnosis isolation rates, and maintenance efficiency, thereby enhancing the maintenance capabilities of communication equipment, has become an important development direction for communication equipment maintenance. The VXI bus interface is not only compact, standard-open, and boasts high data throughput and reusable modules, but its Virtual Instrument Software Architecture (VISA) also solves the compatibility issues between the interface between the computer and instruments and the application software development environment, thus finding widespread application in testing and diagnostic systems. The GPIB standard bus, as a mature and complete standard instrument bus, is an indispensable instrument bus technology in the field of automated measurement in the high-frequency and microwave frequency bands. In system applications, the GPIB standard bus and the VXI bus have inherent compatibility and complementarity in both software and hardware. Combining the two further enhances the system's versatility, functionality, measurement bandwidth scalability, and electromagnetic compatibility. Therefore, the aerospace telemetry and communication equipment testing and diagnostic system adopts a system bus architecture with VXI as the primary bus and GPIB as a secondary bus. I. System Composition The aerospace telemetry and communication equipment testing and diagnostic system comprises three parts: a hardware platform, a software platform, and a TPS (Test Procedure Set). The hardware platform mainly consists of a main control computer, a programmable power supply, measurement instrument modules, a combined portable mobile chassis, a VXI chassis, and other components. The measurement instrument modules include a comprehensive signal generator, a spectrum analyzer, a microwave power meter, a microwave frequency meter, a VXI integrated measurement receiver, a microwave switch, a digital multimeter, a bit error rate tester, an arbitrary wave generator, an oscilloscope, an A/D module, a D/A module, digital I/O, and a matrix switch. The software platform includes system settings management, system calibration/self-test, a TPS development platform, a TPS execution platform, and comprehensive information query functions. TPS includes system-level TPS and circuit board-level TPS for communication equipment. II. System Working Principle For system-level testing of communication equipment, the main test interfaces of the device under test (DUT) are antenna ports, audio interfaces (headphones, microphones), and data ports. The test interfaces of the DUT are connected to the communication equipment test and diagnostic system via ITAs (Interface Adapters), thus forming a test channel and connecting the test instruments to the DUT. Under the control of the main control computer software platform, the test instrument resources send stimuli to the DUT and collect responses to achieve system-level testing of the communication equipment. By comparing the results with the normal values ​​of the test parameters, a conclusion is given as to whether the DUT is normal or faulty. Through the appropriate switching of switch arrays (including microwave switches and relay switches), automatic testing of different types of test parameters is achieved. For the testing and fault diagnosis of communication equipment circuit boards, the main interfaces of the DUT are the edge connectors of the circuit board and RF connectors, such as SMA, BNC, and SMC interfaces. The DUT is connected to the system test instrument resources via a universal adapter board and an ITA, forming a test channel and connecting the test instruments to the DUT. Under the control of the main control computer software platform, and in conjunction with a switch array, the system can freely configure up to 128 pins of instrument resources on the circuit board under test using a combination of automatic and manual methods. Furthermore, through the digital I/O test interfaces on the ITA panel, including digital probes, analog probes, and fixtures, it can test important test signals of unreachable edge connectors on the circuit board. The main control computer serves as the command and control center for the test and diagnostic process, coordinating and controlling the operation of data acquisition and excitation equipment. Test data is sent to a fault diagnosis database for preprocessing. For circuit board-level fault diagnosis, under the control of the TPS (Test System), the test fixtures and probes are guided to gradually penetrate deeper, isolating faults down to the chip level. For system self-testing, under the control of the self-test module of the software platform, statistical querying and sharing of test and diagnostic information are achieved. III. System Software Structure The aerospace telemetry and control communication equipment test and diagnosis system software is based on the aerospace telemetry and control company's software product Fault Doctor 2.0. It has been improved and redesigned to address the specific characteristics of communication equipment testing and diagnosis. It employs technologies such as soft bus technology, dynamic loading technology, COM technology, GDI+ technology, ASP2.0 technology, BCG interface technology, VPP standard instrument interchange technology, test parameter library, and external modules. This establishes an integrated software framework model for communication equipment testing/diagnosis/management, encompassing system-level testing, circuit board-level testing, and circuit board-level fault diagnosis. Interfaces are reserved for remote fault diagnosis. The overall software structure consists of four main modules, each containing several sub-modules. These modules are functionally independent and, under the control of the main control program, transmit functional requirements and data through interfaces for transfer and modification. The four main functional modules include: System Integrated Management (including system activation/deactivation, system self-test/calibration, and system maintenance); TPS Development (using graphical programming or modeling); TPS Execution (completing testing and fault diagnosis of the tested object, providing automatic detection and information prompts); and Integrated Self-Information Query (including basic and advanced queries). With the rapid development of modern communication, electronic, and network technologies, the functions and performance of communication equipment have been greatly improved, while simultaneously placing higher demands on its maintenance and support. A modular, open-source aerospace telemetry and control communication equipment testing and diagnostic system is applicable to system-level and circuit board-level testing and fault diagnosis of various types of communication equipment, enhancing the maintenance and support capabilities of communication equipment. Using this system for system-level and circuit board-level testing and diagnostics of radios, relay equipment, and network terminals can improve maintenance and support efficiency by more than 50% compared to conventional maintenance methods.