Design And Verificatio Platform Development Of Doppler Frequency Offset Estimation And Compensation Algorithm For Highly Dynamic Vehicular Networking Scenario

To effectively alleviate the Doppler frequency extension effect on the performance of communication system in highly dynamic vehicular networking scenario,from three dimensions of the multiband performance difference,service requirements difference and historical data aided,this paper proposes a new hybrid Doppler frequency shift estimation and compensation algorithm,which effectively implements the Doppler frequency shift estimation and compensation and improves the performance and reliability of the communication link,so as to guarantee the services running in the highly dynamic vehicular scenario effectively.The main contributions of this paper include two parts.The first part is to establish the data-aided hybrid estimation and compensation algorithm for Doppler frequency offset.First,a hybrid training array is designed including a fixed sequence and multiple respective sequences.The random correlation combination of the repetitive training sequences is used for maximum likelihood estimation to improve the performance of the estimation algorithm,and the fixed sequence is used for multi-step estimation to achieve the balance of accuracy and complexity of the Doppler frequency offset estimation algorithm.Further,by learning the results of the estimated historical data,the proposd algorithm achieve adaptive adjustment on performing frequency of estimation and compensation.Secondly,on the basis of multiple compensation,the proposed algorithm achieve real-time algorithm accuracy adjustment based on the difference analysis of service requirements.The second part is to set up a software and hardware verification platform for the key technology of Doppler frequency offset compensation facing the highly dynamic vehicular environment.First,we design and build the link level simulation platform of high dynamic vehicle transmission.And based on the USRP RIO software radio platform and EB Propsim channel simulator equipment,we set up the environment of the high dynamic vehicle oriented Doppler frequency shift estimation and compensation of key technical verification hardware platform,using the channel simulator to model the highly dynamic vehicle channel environment,which simulates the normalized Doppler frequency offset at 0.1～0.25 randomly to map the highly dynamic wireless environment.The experimental results verify the accuracy and effectiveness of the Doppler frequency offset estimation and compensation technology,which reduces the BER of the system bit error rate from 0.45 to less than 0.1.The system throughput increased from 19.84Mbps to 26.75Mbps,an increase of 34.82%.