车辆中继的车-车通信系统差错性能分析

摘要

The error performance of vehicle-relayed inter-vehicular communication (FVC) systems is studied based on double-Rayleigh fading model. The statistical properties of the end-to-end signal-to-noise ratio (SNR) are analyzed and the solution to optimal power allocation (OPA) coefficient is presented for the system. A generalized expression of the lower bound on average symbol-error-rate (ASER) for various M-ary modulations is derived through moment-generating-function based approach for the cooperative JVC systems. The method to finding the solution of Chernoff union bound on error probability of the system is provided. Simulation results show that the ASER decreases by applying vehicle-relaying technique in vehicle-to-vehicle communications. The differences between the exact ASER value and its lower bound increase slowly with SNR and the range to the ASER is dete rmined by its lower bound and Chernoff upper bound. Numerical results further indicate that the transmit power can save 3 dB at most through OPA than equal power allocation method in the cooperative FVC system.%研究了双瑞利衰落模型下采用车辆中继技术的车际通信系统的差错性能.分析了系统端到端接收信噪比的统计特性,给出了系统最佳功率分配系数求解结果；利用基于矩生成函数的方法导出了采用M阶调制的协作车际通信系统平均误符号率ASER下界的通用表达式；给出了系统差错概率Chernoff—致界的求解方法.仿真结果表明,在车-车通信中采用车辆中继技术可以减小系统的ASER;分析得出的ASER下界值与其精确值间的差异随着信噪比的增大而缓慢增大；下界值和Chernoff 上界值确定了系统ASER的取值范围；在协作IVC系统中采用最佳功率分配比等功率分配方法最大可节省3 dB的发射功率.