Research Of Spectrum Monitoring System Based On Software Radio

With the development of radio technology,more and more devices are connected to the wireless network,and communication between people is more convenient.On the other hand,this also makes spectrum resources more tight and crowded,bringing radio spectrum monitoring and management.More severe challenges have increased the difficulty of spectrum monitoring.In order to avoid the malicious use of spectrum resources and provide reference for spectrum planning,these radio signals need to be monitored in real time.Software radio can realize different functions with different software modules.It has the characteristics of convenient system upgrade and strong function scalability,which is of great significance for radio spectrum monitoring.This thesis studies the spectrum monitoring system based on software radio.The research content mainly includes the research of spectrum monitoring method,the overall design of spectrum monitoring system,the design and implementation of spectrum monitoring software and the testing and verification of spectrum monitoring system.The specific work of the thesis is as follows:(1)Research on spectrum monitoring methods,focusing on signal detection and separation methods and modulation method identification methods.In this thesis,the power spectrum detection method and the frequency domain filtering method are used to realize the detection and separation of signals by simulation.Based on the decision tree and the distribution of the characteristic parameters of the signals of different modulation methods,a method is proposed to realize the identification of signal modulation modes.Eight modulation modes of AM,FM,2ASK,4ASK,2PSK,4PSK,2FSK and 4FSK are identified,and the correctness and effect of the method are verified by simulation.(2)Based on the overall design of the spectrum monitoring system,based on the analysis of system requirements,the thesis selects Zynq-7000 and AD9361 to form the hardware platform of the system,which can collect signals in the frequency range of 70MHz-6.0GHz and is based on QT platform.To realize the development of spectrum monitoring software,the sub-module designed the overall structure of the software,and the real-time monitoring of the signal is completed by the spectrum monitoring software.(3)The module design and implementation of spectrum monitoring software mainly includes the design and implementation of signal processing module,display module,data storage and reading module and communication module.The software realizes the communication between software and hardware platform through Socket programming.The software can analyze and process the received signals,realize real-time display of signal spectrum map and waterfall graph,detect and modulate signal,analyze frequency band utilization statistically,store data and read data.(4)The testing and verification of the spectrum monitoring system mainly includes functional testing and performance testing,verifying the stability of the spectrum monitoring system and the functions of the spectrum monitoring software,and meeting the requirements of the system.