指数威布湍流模型下高空OFDM-FSO系统误码率分析

BER analysis of high-altitude OFDM-FSO modulation system under exponentiated Weibull atmospheric turbulence model

基于指数威布(Exponentiated Weibull)大气湍流模型,搭建高空平台下的OFDM-FSO通信系统,以误码率为评价指标分析在分别采用K-PSK和M-QAM调制方式下OFDMFSO通信系统的链路性能。仿真结果表明,OFDM-FSO系统在指数威布大气湍流模型下的误码率随着载噪比的增大而逐渐降低,采用PSK调制方式下的误码率性能普遍优于子载波采用QAM调制方式下的误码率性能。不同湍流条件下误码率随载噪比增大的变化趋势存在细微不同,以中、强湍流条件下较为明显。指数威布模型下,接收端孔径平均效应能够有效改善系统误码性能。

Based on the exponentiated Weibull atmospheric turbulence model,the OFDM-FSO communication system in high altitude platform was constructed and the link performance of OFDM-FSO communication system under K-PSK and M-QAM modulation was analyzed by using bit error rate as the evaluation index.The simulation results show that the bit error rate of the OFDM-FSO system under the exponentiated Weibull atmospheric turbulence model decreases with the increase of the carrier-to-noise ratio,and the bit error rate performance of the subcarrier using PSK modulation is generally better than that of the subcarrier using QAM modulation.The change trendency of bit error rate is slightly different under different turbulence conditions,especially,the change of BER are more obvious under the middle,strong turbulence conditions.Under the exponentiated Weibull model,the aperture averaging effect at the receive end can effectively improve the system＇s BER.