FSO链路中基于平均信噪比的自适应功率传输技术

Average SNR Based Adaptive Power Transmission Technique in FSO Links

文章提出了1种基于平均信噪比(Signal-to-Noise Ratio,SNR)的自适应功率传输技术,旨在补偿大气湍流引起的闪烁效应,以提升自由空间光(Free-Space Optical,FSO)通信系统的性能。在无需大气湍流状态信息估计的情况下,根据接收信号的平均SNR来调整发射信号的发射功率,实现基于自适应功率传输技术的大气湍流效应补偿。建立了不同湍流强度下具有不同噪声水平的信道模型,并将所提出的技术与固定阈值判决(Fixed Threshold Decision,FTD)和自适应阈值判决(Adaptive Threshold Decision,ATD)技术进行了比较分析。仿真结果表明,在不同的湍流强度下,该技术的误码率(Bit Error Rate,BER)性能相较于FTD有了显著的提高,并且接近于ATD。因此,该技术可以有效提高FSO链路的通信能力。

In order to compensate for the scintillation effect caused by atmospheric turbulence and improve the performance of free-space optical(FSO)communication system,an adaptive power transmission technique based on the average signal-to-noise ratio(SNR)is proposed.The power of transmitted signal is adjusted according to the average SNR of received signal to realize the compensation of atmospheric turbulence effect based on adaptive power transmission technique without the knowledge of channel information.The channel model is constructed with different noise levels and turbulence intensities,and the proposed method is compared with fixed threshold decision(FTD)and adaptive threshold decision(ATD)techniques.The simulation results show that the proposed technique can significantly enhance the bit error rate(BER)performance compared with FTD,and it is close to ATD under different turbulence intensities.Therefore,this technique can effectively improve the capability of FSO links.