Novel Techniques for Combating DC Offset in Diversity Combined ACO-OFDM

Abstract

In this paper we present two novel techniques of diversity combined asymmetrically clipped optical orthogonal frequency division multiplexing (ACO-OFDM). The techniques are able to achieve better performance than conventional ACO OFDM while being unaffected by the variations in the zeroth subcarrier. Zeroth subcarrier variations are caused by DC offsets present in the biasing of the transmitter light emitting diode and receiver photo diode, and low frequency interference due to background noise sources such as fluorescent and incandescent lamps. Simulation results are presented which show that the new methods achieve better performance than ACO-OFDM.