一种基于MIMO-FSO的最大似然盲检测算法

在多天线自由空间无线光通信(MIMO-FSO)系统中,提出一种基于通用最大似然的序列(MLSD)盲检测算法,使用等增益合并(EGC)获得MIMO空间分集,研究了大气湍流衰落信道不同强度条件下算法的性能。此外,针对MLSD在较长序列长度下的高复杂度,提出一种次优的快速搜寻算法。蒙特卡洛仿真结果显示,所提出的接收机模型在MIMO-FSO系统中,能够获得空间分集,在不同信道条件、中等序列长度条件下,得到接近最优检测的性能。

A generalized maximum likelihood based blind detection for photon-counting MIMO free space optical systems

This paper provides a new method of blind detection based on Generalized Maximum Likelihood Sequence Detection(GMLSD) in Multiple-Input Multiple-Output(MIMO) Free Space Optical (FSO) systems over weak, moderate and strong atmospheric turbulence channels. The detection scheme in this paper can perform sequence detection taking advantage of the spatial diversity in Equal Gain Combining(EGC) MIMO systems without using any kind of channel knowledge. Furthermore, this paper develops a fast search algorithm which is suboptimal and significantly reduces the computational complexity of sequence processing in receivers. Monte Carlo simulation results show the proposed scheme obtains the spatial diversity in MIMO systems and reaches near optimal detection performance by using medium sequence lengths over different atmospheric turbulence fading models.