水下无线光信号的时域展宽特性分析

光信号在海水信道中传输时,受其散射影响导致多径传输,使接收到的信号发生时域展宽。分析了水下无线光传输的散射特性,利用蒙特卡洛统计方法,仿真了激光冲激信号在近海海水中的时域展宽特性;通过拟合不同脉宽的光信号,得到了近海海水中无线光传输的时域展宽模型。结果表明,在近海中冲激信号的时域展宽随传输距离的增加而快速增加,在一定范围内为高斯函数,且近海中光信号的传输距离与传输速率呈指数衰减的关系。

Analysis on Time-Domain Broadening Characteristics of Underwater Wireless Optical Signal

Multipath transmission of laser signal is caused by the optics scattering in undersea, and the received signal will be broadened in time domain. In this paper, the scattering characteristics of undersea wireless optical transmission were mainly analyzed, and Monte Carlo statistical method was used to simulate the time-domain broadening characteristics of laser signal in offshore seawater. Then the time domain broadening model of wireless optical transmission in offshore seawater of different pulse width optical signal was obtained. The results show that the time domain broadening of impulse signal in offshore area is increased rapidly with the increase of transmission distance and meets the Gauss distribution in a certain range, and the relationship between the transmission rate of optical signal and the transmission distance presents exponential decay.