适用于紫外光通信的延迟判决均衡算法

为了消除紫外光通信过程中强烈散射所引起的码间干扰,采用一种带信道估计的最小均方误差-最大似然估计(LMS-MLE)延迟判决均衡算法进行了理论分析和仿真验证。通过选取合适的判决延迟深度来调整LMS自适应滤波器抽头系数进行信道跟踪,获取新的信道估计向量,最后利用MLE均衡算法得到最优序列输出。结果表明,该算法可以明显提升紫外光通信系统的性能,在没有提高复杂度的情况下,性能接近最优MLE均衡算法,并且可以实现信道跟踪,紫外光通信中算法的最佳延迟量取值为20。这一结果对紫外光通信性能提升以及MLE均衡器的工程实现是有帮助的。

Equalization algorithm with delayed decision suitable for UV communication

In order to eliminate inter symbol interference caused by strong scattering in ultraviolet communication, one delay decision equalization algorithm based on least mean square-maximum likelihood estimation (LMS-MLE) with channel estimation was adopted. The theoretical analysis and simulation verification were carried out. The appropriate decision delay depth was selected to adjust the LMS adaptive filter tap coefficient for channel tracking, and to obtain a new channel estimation vector. Finally, the optimal sequence output was obtained by using the MLE equalization algorithm. The results show that, the algorithm can obviously improve the performance of ultraviolet communication system. Without increasing the complexity, the performance is close to the optimal MLE equilibrium algorithm. And the channel tracking can be achieved. The optimal delay of the algorithm in ultraviolet (UV) communication is 20. This result is helpful for improving the performance of UV communication and engineering implementation of MLE equalizer.