Research On Multiple Access Methodfor Joint Sensing And Communication Base Station System

With the rise of intelligent applications such as automatic driving which need urgently communication and sense of high accuracy,Joint Sensing and Communications(JSC)was proposed by academia and industry.On the one hand,the efficient utilization of spectrum resources can come true by merging sense and communication deeply.On the other hand,the cooperation of sense and communication to enhance each other,greatly support intelligent applications such as automatic driving.In the automatic driving scenario,because of the vehicle’s requirements for environmental awareness and high-capacity communication,the vehicle network technology based on the JSC has attracted a lot of attention.Among them,multiple access technology can solve the mutual interference problem caused by the fusion of sense and communication,and is an effective means to improve the efficiency of resource utilization and realize the improvement of sense and communication performance.This paper studies the multi-access protocol of the JSC base station system for the scenario of the Internet of vehicles,and solves the interference problems in the system through the multi-access technology.The research idea is divided into two steps:firstly,the downlink channel and power allocation of the JSC base station based on orthogonal frequency division multiple access(OFDMA)are studied,and the ranging and velocity measurement Cramer-Rao Lower Bound(CRLB)constraints are fully considered.Then,a time-frequency resource allocation algorithm is proposed for vehicle-to-vehicle JSC Sidelink access scenario.The specific contributions of this paper are as follows.1)Firstly,Under the CRLB constraints of radar sensing ranging and velocity measurement,downlink communication total capacity optimization problems are studied.The optimization model fully considers the requirements of large communication capacity and high precision sense in scenarios such as Internet of vehicles.On the basis of establishing the optimization model,subcarrier allocation and power allocation algorithms are proposed.Under the constraints of sense performance,the downlink communication total capacity of the JSC base station are maximized,and the performance tradeoff between communication and perception is studied.The simulation results show that the CRLB constraints of radar ranging and velocity measurement reduce the sum of communication capacity.With the gradual relaxation of the CRLB constraints,the sum of capacity realized by the subcarrier and power allocation algorithm proposed in this paper gradually approaches the maximum sum of capacity of the communication system without the CRLB constraints.2)Secondly,this paper is written for Sidelink access scenario of JSC V2X,establish the JSC Sidelink interference model.In view of the channel contention problems,this paper designs the time-frequency resource allocation algorithm,this algorithm focuses on global optimization,the use of radar sense function to obtain Sidelink relative distance information,to schedule Sidelink resources for vehicle user equipment(VUE).The simulation results prove that,the resource allocation algorithm designed in this paper improves the efficiency of resource utilization and the success probability of Sidelink access.