Research Of LTE Wireless Location Algorithm Based On Channel Fading Error Suppression

LTE Wireless location technology is seriously affected by channel fading in complex urban non line of sight,resulting in poor positioning accuracy.So this paper relies on the National Science and technology support program named “Research and demonstration application of electric vehicle timesharing mode and supporting technology in Mountainous City”,with sub task "human vehicle environment dynamic collaborative service model".So that,this paper based on the background of LTE positioning technology,and carry out the research work.The contents and results of the research are as follows:First,this paper constructed a channel fading error model for complex NLOS urban scenarios.According to the temporal and spatial variation of the signal in the propagation process,the multipath error suppression of the small scale fading is suppressed by increasing the accuracy of the multipath delay estimation of the fast changing LTE orthogonal frequency division multiplexing system;By restraining the power loss caused by long time interference,the path loss error of large scale fading is suppressed.The proposed model reduces the influence of the NLOS channel fading,and improves the positioning accuracy by suppressing the channel fading error.Second,a multipath time delay estimation algorithm based on peak frequency domain sliding correlation search is proposed.In order to solve the problem of low estimation precision and high complexity of the classical multipath time-delay MUSIC algorithm,this paper uses the time-frequency characteristics of LTE downlink orthogonal frequency division multiplexing(WDM)signal,and uses peak frequency domain sliding correlation search to lock the peak to a section and solve the phase deviation matrix in the frequency domain.Simulation results show that the improved algorithm has higher resolution of the first pass;The correlation peak amplitude and deviation are more obvious,and is not susceptible to side lobe effects;The accuracy of the algorithm is high.Third,a transmission loss location algorithm for complex cities based on SINR transmission index is proposed.In order to solve the problem of the low adaptability of the classic TOA algorithm in NLOS scene,this paper analyzes the channel loss of street canyon street corner loss and building loss first,and then introduces SINR transmission loss index to discriminate and adaptively match,and further corrections error positioning accuracy.Experimental results show that the algorithm reduces the error distance between the two estimated values and the reference values,and improves the positioning accuracy.In this paper,the performance of the algorithm is verified by measurement and simulation.The results show that the error probability distribution is stable and the location accuracy is higher than that of the traditional TOA algorithm.