Design Of Communication Tester Spectrum Analyze And Control Module

Communication comprehensive test instrument is designed based on the soft ware radio technology, mainly using in the research, production, testing and maintenance of wireless communication equipments, One of the core functions is the signal spectrum measurement. At present, the widespread use of broadband communications technology, such as frequency hopping and spread spectrum technology, bringing some new spectral measurements challenges. Considering these challenges, this thesis designed a wideband spectral processing module which based on software radio theory.The module use full-digital IF processing method and take "Trigger- Capture-Storage- Analyze " structure as the design architecture to achieve real-time spectrum analysis function. This thesis studied the bandpass filter group delay correction method, got the all-pass filter transfer function through the relationship between minimum phase sequence and its complex cepstrum coefficient; Designed these four trigger functions include FMT(Frequency Mask Trigger), to realize the trigger capture function under different circumstances; Designed a trigger storage mechanism which based on DDR3 SDRAM to realize the sensitive signals collection and storage under different trigger conditions,while the data are reading from DDR3, use address management mechanism to achieve the overlapping data processing. After this, use the window function and FFT engine to calculate the broaddband signals Spectrum. In addition, designed a command arbitration center for these commands parsing which came from PC software, and complete the data transmission task between the software and PCB board to achieve the overall control function.Using a broadband signal source and associated test software, rational design test signals for each functional module. Analysis these experimental results and compared with the design specifications. Shown that the design of this thesis ultimately achieve the expected goals.