摘要
针对星地激光通信下行链路,提出最大天顶角的概念,并给出在大气湍流影响下最大天顶角模型的建立方法.文中以采用OOK调制、APD探测器的链路为例,基于gamma-gamma光强起伏概率密度函数、Webb-Gaussian APD输出模型以及Hufnagel-Valley湍流强度轮廓线,推导了下行链路最大天顶角、近地面湍流强度、误码率三者之间的关系.用数值仿真得到信号光功率为2W的链路中最大天顶角分别与近地面湍流强度、误码率的关系曲线,该结果表明链路可容忍的误码率越大则最大天顶角越大,而近地面湍流强度越大则最大天顶角越小.最后,该文利用非线性拟合方法拟合了最大天顶角关于误码率和地面湍流强度的经验模型.
A concept of ＂maximal zenith angle＂ is proposed for satellite-to-ground laser communication links. A method for building the maximal zenith angle model is presented. We consider links using on-off-keying （0OK） modulation and avalanche photodiode detector （APD）. Relationship among the maximal zenith angel, the nominal value of atmosphere turbulent intensity, and the bit error rate （BER） is obtained. This is done based on gamma-gamma （GG） probability density function （PDF）, Web-Gaussian approximation of APD, and the Hufnagel-Valley model of the atmosphere turbulent intensity. With the laser signal power set at 2W, the simulation results show that the maximal zenith angel is clearly decreased with the nominal value of atmosphere turbulent intensity, and increased with BER. A empirical model of maximal zenith angel is obtained using nonlinear curve fitting.
出处
《应用科学学报》
EI
CAS
CSCD
北大核心
2011年第1期22-26,共5页
Journal of Applied Sciences
基金
中科院知识创新工程三期项目基金(No.KGCX3-SYW-407-03-10)资助
关键词
激光通信
大气湍流
最大天顶角
误码率
经验模型
laser communication, atmospheric turbulence, maximal zenith angle, bit error rate, empirical model
