Design And Implementation Of A Software Defined Radio Based Fake Base Station Identification And Supervision System

The mobile communication network has entered the 5G era,the upgraded security architecture limits the attacks of fake base stations in 5G.However,a large number of terminals in my country still use GSM and LTE networks.Therefore,how to supervision prevent the fake base station is still an important research topic.The current fake base station identification scheme has low recognition accuracy and poor identification timeliness,and cannot provide data support for the sentencing of fake base stations.In view of the above problems,this thesis implements a fake base station identification and supervision system.The main innovative work is as follows:(1)The demodulation module of downlink broadcast link of GSM and LTE cells is implemented.This module uses SDR to receive downlink broadcast signals of GSM and LTE cells,and uses the demodulation software designed in this thesis to demulate GSM and LTE cells downlink broadcast signal.A fake base station identification scheme based on cell broadcast information is proposed.The cell information was decoded by the demodulation module,combining with the base station information database,fake base station identification was realized.(2)A fake base station positioning algorithm based on RSSI is proposed and implemented.The algorithm based on the RSSI of the fake base station reported by multiple signal acquisition devices to construct a distance ratio circle,and the fake base station is located in the overlapping area of the multiple distance ratio circles,and the particle swarm optimization algorithm is used to iteratively solve the actual position of the fake base station,and the effectiveness of the algorithm is verified by simulation and experiments.Combined with the fake base station identification and positioning functions,based on the geographic information system,a fake base station trajectory simulation function is realized.This function provides a reference for law enforcement officers to evaluate the area affected by the fake base station and the number of users by simulating the travel trajectory of the fake base station,and for the criminal behavior of the fake base station sentencing provides data support(3)A fake base station identification and supervision system based on SDR is designed and implemented.The system consists of signal acquisition equipment and supervision platform.The system has ablilities of fake base station identification,positioning and trajectory simulatio.Finally,the system is fully tested to verify the availability and stability...