利用光的轨道角动量传递信息可有效提高信息传输的速率。介绍了光轨道角动量的基本概念和主要特性, 探讨了基于轨道角动量的自由空间光通信的基本原理和典型系统, 并对相关的关键技术进行了分析, 在此基础上, 对基于轨道角动量的自由空间光通信的应用前景和发展趋势作了展望。

The concept of mobile atmospheric laser communication (MALC) is introduced in this paper. Atmospheric attenuation, turbulence-induced scintillation and beam wander cause deep fades in the beam power and degrade the optical channel. The optical transceiver presented in this paper is designed for a MALC test system. Currently achievable hardware performance capabilities for the MALC terminals are used as input parameters to the analysis. A novel optical transceiver structure is designed. Link margin is analyzed using the MALC analysis software, our optical link analysis program. Data rate, bit-error rate, prime transmit power requirements, optical link margin, pulse width, background signal, aperture quality and atmospheric effects drive the optical transmitter requirements. Results are displayed as required aperture size, aperturenumber and the spacing between apertures for a given range and terminal moving speed. The aperture size is parameterized by data rate, transmitting optical power and wavelength. Si-APD and CCD are selected as the main receive detectors. The receiver aperture, detector size (diameter), receiver speed and sensitivity are the main factors to consider in the design of the receiver.