摘要
研究了正交频分复用(OFDM,orthogonal frequency division multiplexing)系统中基于变换域补零的插值方法,深入分析了基于离散余弦变换(DCT)的插值法,利用DCT的能量压缩特性,能有效消除传统基于离散傅里叶变换(DFT,Discrete Fourier Transform)估计算法在信道延时不是采样周期整数倍时产生的频谱能量泄露的问题。针对如何降低导频信道响应估计值中的噪声分量,提出了一种改进的方法,设计了一种适用于DCT变换域的滤波器,通过仿真系统参数变化对改进算法性能的影响,分析和验证了改进算法的有效性。
This paper studies the channel estimation method based on discrete cosine transform（DCT） for OFDM system,Due to the energy compaction properties of DCT,spectral energy leakage of conventional Discrete-time Fourier Transform-based estimation could be mitigated when the path delays are not in integral multiples of sampling period.An improved DCT-based channel estimation method is proposed,and a low-pass filter suitable for DCT domain is designed.Based on the influence of simulation system parameter variation,the effectivity of the improved algorithm is analyzed and verified,and the conclusion is drawn that the channel estimation performance of OFDM system based on DCT transform is more superior.
出处
《通信技术》
2011年第5期34-36,共3页
Communications Technology
基金
东南大学移动通信国家重点实验室开放研究基金资助课题(NO.W200914)
