LS estimator: Performance analysis for block-type and comb-type channel estimation in OFDM system

Channel Estimation in Orthogonal Frequency Division Multiplexing (OFDM) is imperative for cancellation of the impairments introduced by the fading channel. In this paper, the performance of Least Square (LS) estimator is studied for comb-type and block-type pilot insertion schemes over fast and slow fading Rayleigh channels respectively. The channel order increases proportionally with the distortions introduced from the environment. The effect of increase in channel order on the Bit Error Rate (BER) performance of LS estimator for pilot assisted channel estimation techniques is evaluated. Stability of LS estimator in terms of BER performance for block-type pilot arrangement is revealed by the Simulation results. However, increasing the channel distortion by increasing the channel order causes performance degradation of LS estimator for comb-type pilot insertion scheme.