一种基于归一化的抗同频干扰算法

A Co-channel Interference Cancellation Algorithm Based on Normalization

在移动通信系统中,降低频率复用因子可以很好地提升频谱利用率,但同时也带来了同频干扰问题,使用MIC算法可以有效地消除同频干扰,但其仍存在时间复杂度与性能难以调和、收敛速度慢等不足。为此,提出了一种改进型的归一化MIC算法,该算法是最小化干扰原理的一种表现形式,其中的自适应滤波器的权向量在从一次迭代到下一次中,应当以最小方式改变,而且受到更新的滤波器输出所施加的约束。仿真结果表明,算法在保证稳定性和不增加时间复杂度的条件下,拥有更好的同频干扰消除性能。

In the mobile communication system, reducing the frequency reuse factor can greatly improve the spectrum utilization, and at the same time leads to the co-channel interference （CCI） in system. The mono interference cancellation （MIC） algorithm can effectively suppress CCI,but it still has some defects such as difficult harmonization between time complexity and performance, slow convergence rate and so on. Therefore,an improved MIC algorithm based on normalization is proposed. This algorithm is a form of mini- mizing interference principle, in which the weight vector of adaptive filter should change by the method of minimum from one iteration to the next,and be constrained by the output of the updated filter. Simulation results show that the algorithm has a better performance of CCI cancellation than the traditional method with the condition of ensuring the stability and not increasing the time complexity.