能见度对垂直收发模式紫外散射信道的影响

Effects of atmosphere visibility on an ultraviolet scattering channel with a vertical transmitter-receiver

基于光子计数检测信道模型与光子多次散射大气传播模型,通过定量仿真,研究大气能见度对不同收发间距下垂直收发模式紫外散射信道的路径损耗、多径时延扩展与二进制启闭键控(OOK)调制方式下系统可达速率的影响。仿真结果表明:在给定收发间距下,随着天气条件改善、能见度上升,多径时延扩展随之增大,光子在大气传播过程中的多径效应更显著;当收发间距确定后,存在最佳能见度使路径损耗最小,当收发间距增大时,该最佳能见度也随之上升;当收发间距给定时,存在最佳能见度与波特率使系统可达速率最大,当收发间距增大时,最佳能见度逐渐上升,最佳波特率以及对应的可达速率最大值逐渐减小。

The photon counting detection model and the multi-scattering photon propagation model were used to investigate the effects of atmosphere visibility on the path loss and delay spread of an ultraviolet scattering channel with a vertical transmitter-receiver and the achievable data rate with on-off keying（OOK） modulation. Simulations show that, at a given communication range,the delay spread increases with improving atmosphere visibility.When the communication range is set,there is a best visibility where the minimum path loss occurs and this best visibility increases with increasing communication range.For a given communication range,there are a best visibility and an optimum baud rate that maximize the achievable data rate. With large communication ranges,the best visibility increases while the optimum baud rate and the corresponding maximum achievable data rate decrease.