Demodulation Processing And Graphic Display Of Real Time Spectrum Analyzer

As a basic instrument of electronic measurement,spectrum analyzer has been widely used in the fields of national defense electronics,wireless monitoring,RFID and civilian communication measurement.In recent years,with the rapid development of radio frequency technique,the traditional spectrum analyzer has been gradually replaced by real-time spectrum analyze(RTSA).At the same time,the rapid updating of software technology makes the real-time analyzer change greatly in multi-domain data processing and real-time graphic display.Based on the architecture of the real-time spectrum analysis system,the thesis proposes a process method to realize the high precision demodulation of general modulation signal.Meanwhile,the thesis proposes a variety of graphic display technique,which extends the original single and two-dimensional signal display method,so that the instrument can detect and analyze the characteristics of signal in multi-domain.The main results are as follows:1.According to the characteristics of high-speed real-time spectrum analysis system,a transmission driver software based on PCIe DMA is designed in the thesis to solve the problem of traditional instrument data transmission interface speed,which achieve the high speed and stable data transmission.It provides a guarantee for the real-time display and continuous data processing.2.Aiming at efficient real-time multi-domain analysis of 16 QAM,M-PSK and M-APSK communication signal,the thesis uses the amplitude square algorithm,CMA adaptive equalization algorithm and improved dual-mode carrier recovery algorithm for continuous processing of the measured signal.The results show that the timing error,channel distortion and the frequency and phase errors are eliminated.3.In the face of strong signal sudden and transient,combined with the development of the instrument display technique,the thesis studies the technique of waveform cumulative record display including digital afterglow,three-dimensional spectral density,spectral and three-dimensional waterfall.Through the Windows graphics display drive technique,the data is compressed with color level and the changes of the signal in a certain period of time can be vividly visualized.4.Combined with the multi-window test characteristics,the thesis discusses thewindow sub class and multi-window dynamic layout techniques.By means of these techniques,the thesis achieves the encapsulation of the bottom window sub control and the layout of multi windows.At the same time,the thesis studies the eye diagram and symbol table display technique in modulation domain analysis system,which provides a powerful tool for digital modulation analysis of real-time spectrum analyzer.Finally,the thesis realized the design of the whole data processing and graphic display module and carried out the actual verification on the hardware platform of the real-time spectrum analyzer.After verification,we approved that the paper achieved the main functions and test indicators.