BER performance of Superposed ACO-OFDM in multi-path fading channel

Abstract

Demand for Radio Frequency (RF) communications increases in late years. Optical Orthogonal Frequency Division Multiplexing (O-OFDM) has resistance to inter symbol interference (ISI) and multi-path fading. We proposed a Superposed Asymmetrically Clipped Optical OFDM (SACO-OFDM) which is based on ACO-OFDM. In SACO-OFDM, we superpose the conventional ACO-OFDM signal on the another ACO-OFDM signal. Thus, we can use 1.5 times as many subcarriers as the conventional ACO-OFDM. In this paper, we investigate influence of multi-path fading to SACO-OFDM from the view point of the bit error rate (BER) performance. Then, we assume that the impulse response consists of a ceiling bounce model and an exponential-decay model. As a result, SACO-OFDM is advantageous compared to ACO-OFDM when we use multi-level modulation methods.