Vehicle-to-vehicle (V2V) communications is a part of next-generation wireless networks to create smart cities with the connectivity of intelligent transportation systems. Besides, green communications is considered in V2V communication systems for energy sustainability and carbon neutrality. In this scope, radio-frequency (RF) energy harvesting (EH) provides a battery-free energy source as a solution for the future of V2V communications. Herein, the employment of RF-EH in V2V communications is considered where the bit error probability (BEP) of a dual-hop decode-and-forward relaying system is obtained depending on the utilization of antennas at the relay. The multiple antenna power-constraint relay harvests its power by applying dedicated antenna (DA)/power splitting (PS) EH modes and linear (L)/nonlinear (NL) EH models. Moreover, the links between nodes are exposed to double-Rayleigh fading. Finally, the performance of different system parameters is compared using theoretical derivations of BEP. The results provide a comprehensive analysis of the proposed system considering PS/DA-EH modes and L/NL-EH models, as well as deterministic/uniformly distributed placement of nodes. It is observed that PS-EH outperforms DA-EH assuming a placement of an equal number of antennas and distances. Moreover, optimal performance of PS/DA-EH is achieved by allocating more power and increasing the number of antennas for EH, respectively.

翻译：车辆间（V2V）通信是下一代无线网络的组成部分，旨在通过智能交通系统的互联构建智慧城市。同时，绿色通信被纳入V2V通信系统以实现能源可持续性和碳中和目标。在此背景下，射频（RF）能量收集（EH）提供了一种无电池能源解决方案，为V2V通信的未来发展奠定基础。本文研究了RF-EH在V2V通信中的应用，其中基于中继天线使用情况，推导了双跳译码转发中继系统的误比特概率（BEP）。多天线功率受限中继通过专用天线（DA）/功率分割（PS）能量收集模式及线性（L）/非线性（NL）能量收集模型获取能量。此外，节点间的链路经历双瑞利衰落。最终，通过BEP的理论推导比较了不同系统参数的性能。研究结果对采用PS/DA-EH模式与L/NL-EH模型的系统进行了全面分析，同时考虑了节点确定性/均匀分布场景。结果表明：在相同天线数量与距离配置下，PS-EH的误码性能优于DA-EH；此外，通过分别为PS-EH和DA-EH分配更多功率和增加天线数目，可实现两者的最优性能。