超宽带太赫兹通信中天线结构设计及其波束色散影响分析

Design of Antenna Structure and Analysis of Beam Split Effect in Ultra-BandWidth Terahertz Communications

为克服超宽带太赫兹通信中的波束色散,当前已设计了多种基于实时延(TTD)的天线结构,但其功耗大、复杂度高。为解决这一问题,该文提出一种低功耗、低复杂度的基于串行等间距延时器的稀疏射频链天线结构。通过联合优化延时器时延和移相器相位,可以改变子载波波束方向,实现多载波波束扩展与波束聚拢,从而为不同分布场景的用户服务。具体而言,在所提天线结构下,提出一种优化延时器时延和移相器相位的方案将多载波波束扩散到不同方向,实现波束扩展,以服务分布在不同方向上的用户。然后,通过调节时延和相位使所有载波波束对准同一方向,实现波束聚拢,以服务分布在同一方向上的用户。仿真结果表明了所设计天线结构和所提优化方案的有效性。

To overcome the beam split effect in ultra-bandwidth terahertz communications, the True Time Delay(TTD)-based large array antenna structures have been designed, while the power consumption and the hardware complexity both are high. To solve this problem, a serial equally spaced TTD-based sparse radio frequency chain antenna structure is proposed. Based on the designed antenna structure, the beams at all subcarriers can be changed by jointly optimizing the time delays of TTD devices and the phase of phase shifters, obtaining the beam spreading and beam convergence for serving different distributed users. Specifically,to serve users located in different directions, the frequency-dependent beams can be spread to different directions by optimizing time delays and phase shifts to realize beam spreading. Similarly, to serve users located in a single direction, the beams at all subcarriers can be changed to align with the same direction to obtain beam convergence. Finally, simulation results demonstrate that effectiveness of the designed structure and the proposed optimization scheme.