基于轨道角动量的星间激光通信技术

介绍了将轨道角动量（orbital-angular-momentum, OAM)）作为新复用维度的星间激光通信系统设计。轨道角动量理论上具有无限种模态且各模态间两两相互正交，这意味着基于OAM复用的通信系统可大幅度提高频谱效率和信道容量。分别对星间激光链路的发射机和接收机的实现架构进行了介绍，发端采用无衍射贝塞尔-高斯光束进行编码、调制和OAM多路复用；收端利用具有与发端相反的螺旋相位移除OAM光束的方位角相位以恢复光束的平面相位波前，并通过光电探测器、解调器和译码器来恢复数据。此外，还分析了多普勒频率、卫星摆动和背景噪声等因素对于系统的影响。提出的基于OAM技术的星间激光收发系统设计方案对于未来大容量星间通信系统设计与实现具有重要意义。

Inter-satellite optical communications by using orbital-angular-momentum multiplexed

This paper introduces the design of inter-satellite optical communication links by use of orbital-angular-momentum(OAM) as a new multiplexing dimension. In theory, the OAM has infinite number of modes and each mode is orthogonal to each other, which means that the communication system based on OAM multiplexing can greatly improve the spectral efficiency and channel capacity. This paper also introduces the conceptual diagram of the transmitter and receiver for the inter-satellite optical link. The transmitter uses a non-diffracting Bessel-Gaussian optical beams for coding, modulation and OAM multiplexing, and the receiver removes the azimuth phase of the OAM beams with a spiral phase opposite to the transmitter to recover the plane phase wavefront of the beams and recovers the date through a photodetector, a demodulator, and a decoder. In addition, the influence of Doppler frequency, satellite swing and background noise on the system is also described. The proposed scheme of inter-satellite optical communication links based on OAM technology is of great significance for the design and implementation of future high-capacity inter-satellite communication systems.