Performance Analysis of Mimo-ofdm Receiver Using Modified Pts Technique

Partial Transmit Sequence is one of the distortionless methods to reduce the peak-to-average power ratio (PAPR) in Orthogonal Frequency Division Multiplexing (OFDM) systems. It is an attractive method since it provides PAPR reduction without any degradation in bit error rate (BER) performance. PTS has high computational complexity which increases exponentially with increase in subblocks. But modified PTS technique of PAPR reduction has decreased this computational complexity by using a neighbourhood search algorithm for finding the optimum set of phase factors required for independent phase rotation of the symbols in each subblock. The potential capability of the modified PTS technique is explored in MIMOOFDM systems for PAPR reduction and its performance is evaluated. In this paper, the performance of MIMO-OFDM system employing modified PTS technique is investigated by using Least Square (LS) and Minimum Mean Square Error (MMSE) channel estimation methods. The performance of the system is evaluated in terms of mean square error (MSE) and bit error rate (BER) for different subblock sizes and different subcarriers. The simulation results depict improved BER performance with PAPR reduction by increasing the subblocks. The results also show that there is a slight degradation in BER with increase in number of subcarriers.