设计了一种基于紫外发光二极管(LED)的大气散射通信系统,利用非视线单次散射模型仿真分析了紫外光大气散射通信的接收光功率与通信距离之间的关系以及不同宽度的发送光脉冲在接收端的脉冲波形展宽.构建了紫外光散射通信实验系统,实现了语音和数据传输,并对系统的通信距离和收发仰角进行了实验研究.仿真分析与实验结果显示:日盲区紫外光在大气中散射传输时由于大气粒子的强烈散射与吸收,传输损耗较大,距离每增加10倍,接收功率下降20dB,因此日盲区紫外光大气散射通信适用于近距离通信场合 近距离传输时散射造成的光脉冲多径展宽为微秒量级,对中低速通信系统影响较小 单个紫外LED发光功率较低,可通过多个LED阵列来提高发射功率,增大通信距离.
A scattering communication experiment system using ultraviolet light emitting diodes(LEDs) in atmosphere is designed.Based on the non-line-of-sight single-scatter propagation model,the relationship between the received power and the communication distance and the received pulse extension at different transmitted pulse durations for ultraviolet scattering communication in atmosphere are simulated.An experimental system of ultraviolet scattering communication is implemented to realize the voice and data transmission.The communication distance and the apex angle of the system are also studied.The results of the simulation analysis and experiments indicate that the loss of ultraviolet scattering transmission in atmosphere is high because of the particle scattering and absorbing in solar-blind zone;that is, the received power can descend 20 dB with the distance increasing 10 times.Therefore,the ultraviolet scattering is fit for short range communication.In short range,the pulse extension due to scattering is at microsecond order and its influence for low and moderate bit rate communication systems is weak.Since the light output power of a single ultraviolet LED is low,a multiLED array can be used to increase the transmit power and extend the communication range.