Reduced number of pilot in comb-type pilot arrangement by using modified least square channel estimation for OFDM system

A modified least square algorithm (MLS) for wireless channel estimation at comb-type pilot arrangement in QAM signals for OFDM system is presented. The proposed algorithm aims to reduce number of pilot tones in each OFDM symbol because insert more pilot symbols lead to bandwidth expansion or data rate reduction [1-2]. The simulation results for MLS algorithm showed a good performance in noisy wireless channel and the performances of the presented technique and LS have been compared with different SNR as well as measuring bit error rate verses signal to noise ratio with 4-QAM as a modulation schemes.