Channel Estimation and Interference Cancellation for OFDM Systems Based on Total Least Squares Solution

In this paper, the authors study the effects of interference to channel estimation and present an iterative total least-squares algorithm for channel estimation by using the conjugate gradient method in time-varying multipath fading channels. The Doppler shift of fast-fading channels will generate Inter-Carrier Interference (ICI), hence, degrade the performance of Orthogonal Frequency-Division Multiplexing (OFDM) systems. Furthermore, when the length of Channel Impulse Response (CIR) overstep the duration of Cyclic Prefix (CP), it will cause inter-symbol interference (ISI) and degrade system performance severely.