基于BIC停止准则的改进A~* OMP信道估计算法

AN IMPROVED A~* OMP CHANNEL ESTIMATION ALGORITHM BASED ON BIC STOPPING CRITERION

在高速移动场景下,由于多普勒频移的影响,OFDM系统会产生严重的载波间干扰,从而影响无线通信链路的质量。为弥补该缺陷以保障通信链路的质量需求,需要对高速移动通信信道进行准确估计,然后通过均衡算法进行补偿。已有的A~* OMP算法是一种基于多路径搜索和优选的改进OMP算法,与传统OMP算法相比,虽然能够更加接近全局最优解,但其使用的停止准则在高速移动通信信道估计中性能表现欠佳。为此,提出一种运用BIC停止准则的改进A~* OMP算法,对高速移动通信信道进行估计。仿真结果表明,BIC停止准则比原有准则具有更好的信道估计性能。该改进算法在350 km/h的场景下,与OMP算法相比,约有0.5 dB的性能提升。

In the high-speed moving scene,due to the influence of Doppler frequency shift,there will be serious inter carrier interference to the OFDM system,which affects the quality of the wireless communication link.In order to compensate for this defect and guarantee the quality of communication links,it is necessary to estimate the channel accurately for high-speed mobile communication,and then compensates it by equalization algorithm.The existing A*OMP algorithm is an improved OMP algorithm based on multi path searching and optimization.Compared with the traditional OMP algorithm,it can be closer to the global optimal solution,but it is found that the stop criteria used in the existing algorithms are not good in channel estimation.Therefore,this paper proposed an improved A*OMP algorithm using BIC stopping criterion to estimate high-speed mobile communication channels.The simulation results show that the BIC stopping criterion has better channel estimation performance than the original criterion.In the scene of 350 km/h,the improved algorithm has a performance improvement about 0.5 dB compared with the OMP algorithm.