Sparse channel estimation using orthogonal matching Pursuit algorithm for SCM-OFDM system

In this work, we analyzed channel estimation for SCM-OFDM system using Compressive sensing technique on frequency-selective multipath channel. The pilot aid based channel estimation techniques which uses training sequence are bandwidth inefficient. Compressive sensing is a bandwidth efficient technique in which only fewer pilots are used to estimate channel state information. The simulation result obtained for channel estimation using Orthogonal Matching Pursuit method shows 4% reduction in BER.

Introduction

Orthogonal Frequency Division Multiplexing (OFDM) is a multicarrier modulation technique has emerged as the most favorable modulation scheme for a broadband wireless communication system. OFDM has many advantages over single carrier system, however, it is known that OFDM system is very sensitive to carrier frequency offset; PAPR and channel state estimation errors. The channel state information plays a vital role for coherent data detection. Errors in channel state information affects the signal to noise ratio (SNR) at the receiver and degrades the performance of the OFDM system. Thus, it is very important to obtain correct channel state information through proper channel estimation techniques.