Design And Implementation Of Rof Based Distributed Spectrum Monitoring Platform

With the advancement of technology and the development of society,more and more mobile devices into daily lives.However,what it brings with is the trouble to spectrum management.Increasingly complex of electromagnetic spectrum environment makes the work of traditional monitoring system difficult.Lack of bandwidth,poor flexibility,limited coverage area,cannot achieve signal location,etc.,disadvantage of traditional system increasingly highlight.What is more,the defects of transmission of radio frequency signal,such as high loss,electromagnetic interference and so on,also making the traditional spectrum monitoring system faces a huge challenge.For that type of problems,we propose the idea of distributed design and the combination of RoF technology.The main contents and achievements are as follows:According to the stream of data and difficulty in achieving precision location in traditional electromagnetic spectrum monitoring system,grid design is proposed,which is designed to a form of internal network.It is designed to a mode of modularization by nodes at each level to parts the massive amount of stream of radio data,and the form of internal network to realize data sharing,which make the system of monitoring work of network deployment flexibility,and putting it on practice quick.Moreover,it also is a great boost to achieve signal precision location by the method of multi sensor.This system of monitoring can be more intelligent through the instrumentality of data fusion and storage.To solve the issue that low-bandwidth and high-loss of transmission of radio frequency signal,the concept of integrating RoF into the electromagnetic spectrum monitoring is recommended.Distributed spectrum monitoring system syncretizes the vantage of RoF,high-bandwidth,low-loss,and anti-interference into one,so that its performance can be further improve.The new-type system will be able to obtain higher bandwidth and farther transmission distances.Hence,it accompanies by stronger performing,more real-time,more coverable,more flexible,wider applicability,etc.In this paper,a demo platform of RoF based distributed spectrum monitoring is built in Beijing University of Posts and Telecommunications,and a performance testing of this platform will be done.Under the 20MHz?3GHz operating frequency,a testing of Noise Figure,Three-order Point,SFDR,EVM and so on of remote node,fiber link and central control is carried out.The result show that the demo platform performs great in the dynamic range-42?-8dBm of input where EVM is less than 5.6%.While the software for this demo platform coded by Microsoft.net Framework is finished and its features have been showed in this paper.