Design And Implementation Of Spectrum Analysis Function For Portable Communication Interface Tester

Modern communication systems are becoming increasingly large and complex, in a dedicated communication system, types of equipment includes a control subsystem, a communication computer, a signal conversion apparatus, terminal apparatus, and so on. With so many types of equipment, the fault detection and location of communication equipment becomes more and more difficult.Communication equipment maintenance often require field testing, fault diagnostic equipment should not be too much. Maintenance personnel are more likely to make mistakes when there is too much variety of test equipment, and resulting in low efficiency of the test, the high cost of hardware. Portable communication interface designs the functions of interface packet inspection and spectrum analysis, meet the fault diagnosis and positioning of the majority of communications equipment in a dedicated system.The paper studies the basic principles and techniques of spectral analysis, focuses on the design and validation of the spectral analysis method whitch includes decimation filter bank design technology and discrete spectrum analysis and correction technology, implement the functions of interface packet inspection and spectrum analysis of the interface tester.First, the spectrum analysis method is designed. On the basis of the test requirements and key technologies of spectral analysis, this paper designs an algorithm method whitch includes decimation filter bank design technology and discrete spectrum analysis and correction technology, and the algorithm is simulated with Matlab.Second, the software design is realized. According to the features of the spectral analysis algorithm program and hardware platform, the paper presents the implementation of the interface detection and spectrum analysis. In this paper, the various modules of interface detection and spectral analysis are implemented on FPGA, and the behavioral simulation is made with the ModelSim tool. In the Linux environment, a graphical interface of spectrum display and settings is designed.Third, the implementation result is verified. Each module is debugged and verified on the hardware platform of the interface tester. The test results show that it can realize the spectrum analysis for1to30MHz signal with50Hz minimum resolution bandwidth. The frequency accuracy and the amplitude accuracy is1.0%and5.0%, respectively.In this thesis, the function of interface detection and spectrum analysis is researched and designed, whitch improves the efficiency of fault diagnosis of the communication device interface and its internal board, reduces equipment maintenance complexity, and has good value in use.