Performance evaluation and comparison of spatial modulation and non‐DC MIMOm‐CAP techniques in indoor VLC system

Abstract

In this paper, we propose and apply two novel schemes of multi-band carrierless amplitude and phase (m-CAP) modulation for spatial modulation (SM) based visible light communications (VLC) systems. In SM, both spatial and signal constellation are utilised to improve the performance of the m-CAP system. Here, we have adopted the non-DC m-CAP which is a power efficient technique with no DC-bias. The bit error rate (BER) performance and the spectral efficiency of the proposed systems are compared with single-input single-output (SISO) and multiplexing multiple-input multiple-output (MIMO) m-CAP systems. Results demonstrate that non-DC m-CAP, with the same spectral efficiency as that of SISO m-CAP, outperforms other schemes in terms of BER due to its power efficiency, however a higher spectral efficiency can be achieved by the SM-MIMO m-CAP scheme.

A Hybrid Variable m-CAP-Based Indoor Visible Light Communications and Fingerprint Positioning System

“…Recently, carrier-less amplitude and phase (CAP) modulation, as a surrogate to OFDM, has been proposed for VLC, where the carrier frequencies are produced by simple and cost-efficient finite impulse response (FIR) filters. In CAP (i) there is not any fast Fourier transform (FFT) and inverse FFT (IFFT) as in OFDM, which reduces the complexity of the VLC system; and (ii) is more robust against the LED nonlinearity given that PAPR values are lower compared with OFDM [21]. Nevertheless, a flat frequency response, which is required for optimal CAP performance, represents a substantial challenge towards implementing CAP in VLC.…”