提出了一种基于双滑动窗的检测算法,对信道冲激响应(CIR)进行检测。在采用相干解调的正交频分复用(OFDM)系统中,信道估计的精度对接收机性能有着重要影响。传统的0FDM时域CIR计算法通常采用简单的门限检测,在检测小功率成分时,由于受噪声影响,容易发生误检或漏检,导致估计精度降低。该文在研究小功率CIR成分产生原因与分布特征的基础上,提出了一种改进的检测算法,并对检测性能进行了理论分析和仿真。仿真结果表明,该算法能够有效提高信道估计精度,改善系统误码性能。
A detection algorithm based on dual-sliding-window is proposed for the detection of channel impulse response (CIR). In OFDM systems with coherent demodulation, the precision of channel estimation has a significant impact on the performance of receivers. However, traditional threshold detection algorithms adopted by time domain channel estimation of OFDM systems is sensitive to noise. In the presence of low-level CIR components, false detection and miss detection occur frequently if the traditional method is adopted, resulting in an inevitable precision loss. According to the cause and the characteristic of low-level CIR, an improved robust CIR detection algorithm is derived in this paper. The detection performance is investigated and simulated. Experimental results verified the theoretical analysis and the validity of the proposed scheme.