Achievable rate of DCO-FBMC with low-resolution ADCs for optical wireless communication

Abstract

Recently, a novel direct current-biased optical filter bank multi-carrier (DCO-FBMC) scheme has been proposed for optical wireless communication (OWC) in intensity modulation and direct detection channel. Although the DCO-FBMC scheme supports fully asynchronized multi-user uplink transmission and has been proven to have higher spectral and power efficiency than direct current biased optical orthogonal frequency division multiplexing (DCO-OFDM), its achievable data rates, the fundamental performance metric from information theory perspective, has not been fully unveiled. In this paper, we study the uplink achievable rate and region of the DCO-FBMC system for OWC. Because of the low cost implementation of the realistic OWC system, we consider using low-resolution analog-to-digital converters (ADCs) instead of full-resolution ADCs at the receiver, and study its impact on the achievable rate of the DCO-FBMC system. Simulation results indicate that although using low-resolution ADCs causes loss of system achievable rate, the performance of the 4-bit quantized DCO-FBMC system is very close to that of the full-resolution DCO-FBMC system. In addition, compared with DCO-OFBM, the maximum achievable rate of each user in DCO-FBMC system is larger. Moreover, the DCO-FBMC system with 4-bit quantization gets larger achievable rate region than the full-resolution DCO-OFDM system, especially in the case of oversampling. Therefore, our paper show that from the achievable rate perspective, using the DCO-FBMC system with low-resolution ADCs is a good candidate for optical wireless communication.