On reducing the effects of clipping in an enhanced Orthogonal Frequency Division Multiplexing system

Abstract

Orthogonal frequency division multiplexing (OFDM) is a communication technique that divides a communication channel into a number of equally spaced frequency bands. One major problem, which degrades the OFDM performance, is its high peak average power ratio (PAPR). Nowadays,clipping has become a well known technique in reducing PAPR due to its simplicity. However, this technique has some effects which will degrade the performance of an OFDM system.In this paper, a new OFDM system with an enhanced clipping technique has been proposed, the effects of clipping have been analyzed and the system is evaluated by integrating most of its significant features including convolutional forward error control coding and oversampled inverse fast fourier transform (IFFT), in order to minimize the effects of clipping. It is shown that the bit error rate (BER) of clipped OFDM signal is improved by using this proposed system as well as the PAPR is further reduced as compared to the conventional technique.