An Analysis of the Bias-Property of the Sample Auto-Correlation Matrices   of Doubly Selective Fading Channels for OFDM Systems
  This paper derives the analytic expression of the sample auto-correlation matrix from the least-squared channel estimation of doubly selective fading channels for OFDM systems. According to the expression, the sample auto-correlation matrix reveals the bias property which would cause the model mismatch and therefore deteriorate the performance of channel estimation. Numerical results demonstrate the bias property and corresponding analysis. 
Xiaochuan Zhao (1), Tao Peng (1), Ming Yang (1) and Wenbo Wang (1)   ((1) Beijing University of Posts and Telecommunications...