The Spectrum Monitoring And Acquisition System For Wideband Transient Radio Signals

With the development of wireless technology,more and more wideband transient signals appear,such as radar pulse,frequency hopping signal and kinds of unknown interferences,and how to monitor and capture these siagals becomes a difficult problem.Traditional swept-frequency spectrum and vector-signal analysis technology can not monitor such signals of short duration,fast processing capability of the hardware and the real-time spectrum analysis technology can effectively solve this problem.Through the research of sampling technology,digital signal processing technology and high-speed data transmission technology,this project combines the high performance FPGA and digital fluorescence technology.We develop a wideband transient signal spectrum monitoring and acquisition system for 140 MHz IF with 70 MHz bandwidth.The hardware platform adopts PCIE board with high performance FPGA as the digital s ignal processing core,and uses the application software to complete the signal spectrum customized display and flexible control.In accordance with the performance demand of eac h function module,this paper first introduces the design and implementation of hardware platform,including circuits of data sampling,data processing and transmission.Secondly,focusing on the logic design of data processing core--FPGA,we realize real-time display of the signal characteristics with three dimensions--the frequency,amplitude and frequency spectrum amplitude hits,by the digital phosphor technology(DPX)and seamless processing and transmissing of the spectrum data stream,;and FPGA logic is designed to complete interface of the clock synthesis chip DDS and a new generation of computer bus,PCIE(PCI Express).Then this thesis introduces how to develop driver to realize the identification and control of PCIE card,and focuses on the design and implementation DMA transmission which is the key of rapid transmissio n of mass data.We describe the software design from the view of function and efficiency.By design of various spectrum display methods,spectrum monitoring rgets better visual improvement.With multi-thread design,the running efficiency of the software improves and the congestion situation avoids.Finally,this thesis summarizes the theoretical and practical significance of the design and development,describes the main properties and characteristics of the system,and puts forward the research ideas and content to improve the overall performance of the system.