无相位反馈的分布式发射波束成形技术研究

分布式发射波束成形技术是实现协作通信的一种有效方式,而分布式发射波束成形面临的主要技术挑战有发射信息共享、载波同步、发射时间同步等。本文针对这些技术挑战利用时分双工系统前后向信道的一致性,提出了一种不需要在节点之间反馈相位控制信息的分布式发射波束成形技术。在此基础上,发射节点和目标节点之间数据传输采用OFDM技术,提出了对每个子载波信号分别进行发射波束成形的实现方法。

Distributed Transmit Beamforming without Phase Feedback

Distributed transmit beamforming is a effective form of cooperative communication,however,The main challenges of distributed transmit beamforming include coordinating the sources for information sharing and timing synchronization and,most crucially,the distributed carrier synchronization so that the transmissions combine constructively at the destination.In this paper,we propose a distributed transmit beamforming method without any phase feedback between nodes.The concept of our approach is using reciprocity in a time division duplexed system,so that the phase offset of the forward path compensates that of the backward path;as a result,the signals from different nodes in-phase combine at the destination.We also propose a transceiver prototype which is based on the OFDM technique,beamforming can be performed separately for each subcarrier.