非完美信道信息下LTE-V2V通信最优功率控制

摘要

To suppress the co-channel interference between cellular users and vehicle-to-vehicle (V2V) us-ers in long-term-evolution (LTE) V2V communication system ,an optimal power control scheme for energy effi-ciency (EE) maximization is presented with imperfect channel state information .In the scheme ,the characteris-tics of time varying vehicular communication are described by the variation of communication distance between V2V users ,and the co-channel interference of LTE-V2V communication system is modeled by stochastic geom-etry .Meanwhile ,the feasible region of V2V users' transmission power is obtained under the constraint of guar-anteeing outage probability of cellular users and maximizing transmission power of V2V users .Further ,the EE maximization target function of V2V users is formulated to solve the optimal power of V2V users .Numerical results show that the average sum rates can be maximized by adjusting the access density of V2V users and the EE of the proposed scheme can be improved in comparison with that of the previous maximum transmit power allocation scheme under different maximum communication distances of V2V users .%针对非完美信道状态信息下 LTE-V2V (long-term-evolution vehicle-to-vehicle)通信系统中 V2V用户与蜂窝用户频谱复用带来的共道干扰问题,提出了一种以最大化能效为目标的最优功率控制方案.该方案通过V2V用户间通信距离的变化来刻画车载通信的时变特性,并利用随机几何理论对LTE-V2V通信系统中的共道干扰进行数学建模.同时,在蜂窝用户的中断概率和V2V用户最大功率约束条件下,得到V2V用户传输功率的可行域.并在此基础上,建立起最大化V2V用户能效目标函数,求解得到 V2V 用户的最优功率.数值分析表明,通过调整V2V用户的接入密度可最大化平均和速率,并且在不同V2V用户最大通信距离下,提出的功率控制方法所对应的能效均大于先前的最大功率分配方法所对应的能效.