Study of Performance of an OFDM Transceiver Using SDR Platform

Abstract

One of the most extensively used modulation scheme in digital communication is orthogonal frequency-division multiplexing (OFDM) in which the data to be transmitted is encoded on multiple carrier frequencies. Fast Fourier transform is used in OFDM due to which the subcarriers can overlap with each other and transmit, without loss in information. The performance using OFDM systems is good in multipath environments due to the fact that the subcarriers are transmitted at a lower data rate. The peak-to-average power ratio (PAPR) for an OFDM signal is large, which is a disadvantage in the current OFDM technology. The signal at the transmitter can be clipped before amplifying in order to reduce the effect of PAPR. In addition to this, OFDM also suffers with the problems of channel fading, phase noise, phase distortion, and image rejection. In this study of OFDM transreceivers, with the help of GNU Radio Companion and SDR, we have made an attempt to create a simulation environment similar to real-time channel conditions, by considering the parameters such as bit error rate, channel fading losses, and Doppler spread, and analysed the performance of OFDM transreceiver system.