近年来，随着射电望远镜外差式阵列接收机的发展，基于相位光栅技术的波束分离器在亚毫米波长范围内得到了重要的应用，它能够将单个本地振荡器信号经过分束同步传送到超导SIS/HEB混频器阵列接收机中。由于太赫兹频段相位光栅的特征尺寸在亚微米级，其加工精度直接影响器件性能，给微加工技术带来巨大挑战。基于此，笔者所在课题组结合相位编码超材料技术设计了一种新型的太赫兹四波束分离器，仅需利用单层超材料编码单元便可实现宽带电磁波束的分离，波束转换效率高，结构简单且易于加工，同时反射波束的方向可灵活调节。为了与实际测试系统相匹配，着重研究了不同入射角度下的波束分离，并得到了最佳的斜入射角度范围（小于30°），相对工作带宽可达52%，反射的四个波束功率相差不超过10%，这为太赫兹频段射电望远镜超导混频器阵列接收机的本振信号功率分配提供了新的解决方案，也有利于其他新型太赫兹功能器件的设计和发展。

In recent years, with the development of heterodyne array receivers of radio frequency (RF) telescope, beam splitters based on phase grating technology have gained important applications in the sub-millimeter wavelength range. It is capable of transmitting a single local oscillator signal to the superconducting SIS/HEB mixer receiver array by splitting beam synchronization. Due to the characteristic size of the terahertz phase grating at sub-micron level, its machining precision directly affects the performance of the device, which brings great challenges to the micro-machining technology. Based on this, a new terahertz four beam splitter combined with phase coding metamaterials was designed. Only one single-layer metamaterial coding unit can be used to realize the separation of broadband electromagnetic beam and high beam conversion efficiency. The structure of THz beam splitter is simple and easy to process, while the direction of the reflected beam can be flexibly adjusted. In order to match the actual test system, we focused on beam separation at different angles of incidence and obtain the best range of oblique incidence angles (less than 30°). The relative bandwidth is 52%, and the reflected four beam powers differ by no more than 10%. This provides a new solution for the local oscillator signal power distribution of terahertz superconducting mixer array receivers of RF telescope, and also facilitates the design and development of other new terahertz functional devices.