Journal article

Time-slot coding scheme for multiple access in indoor optical wireless communications

Tian Liang, Ke Wang, Christina Lim, Elaine Wong, Tingting Song, Ampalavanapillai Nirmalathas

Optics Letters | OPTICAL SOC AMER | Published : 2016

Abstract

This letter proposes what we believe is a novel time-slot coding (TSC) scheme to provide optical wireless communications to multiple users simultaneously with limited multiuser interference. We studied the proposed TSC experimentally and our results show that the code alignment tolerance, due to imperfect timing during the code generation process in practice, is 90.2%, 91.8%, and 93.1% with 4-QAM modulation at the received optical power of -22  dBm, -20  dBm, and -18  dBm, respectively. Furthermore, we also demonstrated a proof-of-concept experiment for simultaneous wireless connectivity for up to five users at multiple gross data rates (0.5 Gbps, 1  Gb/s, 1.6  Gb/s, 2  Gb/s, and 2.5  Gb/s).