针对移动平台空间光通信信道的大气湍流随机性强、指向误差大和链路高动态性等问题,建立适合于移动平台的大气信道模型,并进一步推导出采用脉冲调制(PPM)调制的通信系统端到端信道容量和中断概率的解析表达式。仿真分析了在大气弱湍流、中强湍流两种情况下,信噪比、系统分集、指向误差及通信距离等对通信系统中断概率的影响。结果表明,指向误差不宜超过1mrad;通信距离每增加1km,中断概率上升8~11dB。
With the wide applications of free spa ce optical communications recently,the communication link based on mobile platfo rm ha s become one of hot research topics.By considering the influence of more random atmospheric turbulence,worse pointing errors and highly dynamic link on the tra nsmission performance of mobile multiple-input multiple-output (MIMO) free spa ce optics (FSO) communication systems,this paper establishes a channel model for the mobile platform.Moreover,an analytical expression is der ived for the end-to-end channel capacity and outage probability of mobile MIMO FSO communication systems.Finall y,the effects of signal to noise ratio,pointing errors and link distance on outage probability are analyze d through computer simulation under the weak and strong atmospheric turbulence cases,respectively.Simulation results show that pointing error should not be more than 1mrad,and the outage probability rises between 8dB and 11dB as the communication distance increases 1km when the communication system works pro perly.