基于相位旋转的Femto系统干扰检测算法

Phase Rotation-Based Interference Detection Algorithm for Femto System

为消除Femto系统中导频信号对同道干扰检测精度的影响,提出了差分相位旋转干扰检测(DPRID)算法.该算法利用导频信号2-范数相等的特点,对导频信号的接收信号进行相位旋转,使得多个导频信号的接收信号相同,然后充分利用干扰加噪声均值为零的特点估计频域信道,从接收信号中消除导频信号的贡献,从而直接估计同道干扰加噪声的能量.差分计算提升了统计数据量,降低了同向增强和逆向抵消效应,可最大程度地从导频信号中提取信息.仿真结果表明,单天线时与正交干扰检测算法(OID)相比,DPRID算法相对估计误差的方差下降了9.84 dB,相对估计误差下降了4.35 dB.

In order to eliminate the impact of pilot signals in Femto system on the accuracy of cochannel interfe-rence detection,a novel algorithm named differential phase-rotation interference detection（DPRID） is proposed.In this algorithm,according to the equal 2-norm characteristic of the pilot signal,the received signal is rotated to equate the components of the pilot,and the channel in frequency domain is estimated according to the characteristic that the mean interference plus noise is zero.Thus,the contribution of the pilot signal to the received signal is eliminated and the power of cochannel interference plus noise can be directly estimated.With the introduction of difference calculation,the statistical data amount increases,both the enhancement in accordant direction and the counteraction in reverse direction degrade,and most information can be acquired from the pilot signal.Simulated results indicate that the proposed DPRID algorithm outperforms the orthogonal interference detection（OID） algorithm,with a variance of relative estimation error of 9.84dB and a relative estimation error of 4.35dB when single antenna is configured.