Design Of Digital Processing Front-end Module For Real-time Spectrum Analyzer

With the development of modern wireless communication technology,faster timevarying frequency signals become more widespread.The traditional spectrum analyzer cannot satisfied measuring demand of all kinds of signals of sudden short pulse width.This thesis provides a digital front-end module of real-time spectrum analyzer which id satisfied with short burst pulse.This thesis firstly introduces real-time spectrum analyzer digital front-end processing module in detail.It includes high speed and high precision acquisition,digital frequency extraction,analysis bandwidth filtering,real-time overlapping FFT processing etc.About the front-end acquisition and data preprocessing module,thesis designs the correction of sampling data and digital logic,reception of high-speed ADC acquisition to amplitude correction of data receiving and transmitting.Then according to the real-time analysis of variable bandwidth demand under the digital frequency conversion and decimation module is designed.Point at the peculiarly overlapping data processing of Real-time Spectrum analyzer.This thesis introduces the work patterns of overlaps in real time patterns and comparison of advantages relative to non-overlapping.And according to the update rate requirements of the display,research on seamless frequency domain display and overlapping frame parameter setting method of real time spectrum analyzer.Improving the testing efficiency of the analyzer.The relationship between the time parameters of the 100%POI(capture probability)and the analysis of the overlap rate analysis points is studied.The setting range of the overlap rate is analyzed.And a parallel scheme to achieve higher overlaps is designed.In time domain waveform to frequency domain conversion module,the instrument coupling relationship between RBW,analysis bandwidth,analysis points and overlap rate is studied.The FFT algorithm is selected by analyzing the requirement of the time frequency conversion processing speed of the real time spectrum analyzer,and the time frequency domain conversion design is realized based on the FFT IP core.The functions of the front-end modules of the real-time spectrum analyzer are tested by MODELSIM,MATLAB,chipscope and other simulation software.The real-time spectrum analyzer platform,signal source and other instruments are combined to debug with the host computer software.The theoretical and actual values are compared and analyzed to verify that the functions and indexes of each functional module basically meet the actual needs.