We generalize an existing low-cost analog signal processing concept that takes advantage of the periodicity of vehicle-to-vehicle broadcast service to the transmitter side. In particular, we propose to process multiple antennas using either an analog beamforming network (ABN) of phase shifters, or an an antenna switching network (ASN) that periodically alternate between the available antennas, to transmit periodic messages to receivers that have an analog combining network (ACN) of phase shifters, which has been proposed in earlier work. To guarantee robustness, we aim to minimize the burst error probability for the worst receiving vehicular user, in a scenario of bad propagation condition that is modeled by a single dominant path between the communicating vehicles. In absence of any form of channel knowledge, we analytically derive the optimal parameters of both ABN and ASN. The ABN beamforming vector is found to be optimal for all users and not only for the worst receiving user. Further, we demonstrate that Alamouti scheme for the special case of two transmit antennas yields similar performance to ABN and ASN. At last, we show that the derived parameters of the two proposed transmission strategies are also optimal when hybrid ACN-maximal ratio combining is used at the receiver.

中文翻译：

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用于周期性广播V2V通信的鲁棒模拟波束成形

我们归纳了现有的低成本模拟信号处理概念，该概念利用了到发射机侧的车到车广播服务的周期性。特别是，我们建议使用移相器的模拟波束形成网络（ABN）或在可用天线之间定期交替的天线交换网络（ASN）处理多个天线，以将周期消息发送到具有模拟组合的接收器移相器网络（ACN），这是在较早的工作中提出的。为了保证鲁棒性，我们的目标是在通信车辆之间的单个主导路径模拟的传播条件恶劣的情况下，使最差的接收车辆用户的突发错误概率降至最低。在缺乏任何形式的渠道知识的情况下，我们通过分析得出ABN和ASN的最佳参数。发现ABN波束成形向量对于所有用户都是最佳的，而不仅是接收效果最差的用户。此外，我们证明了针对两种发射天线的特殊情况的Alamouti方案产生的性能与ABN和ASN相似。最后，我们表明，当在接收器处使用混合ACN-最大比率组合时，两种建议的传输策略的导出参数也是最佳的。