Edinburgh Research Explorer

Bidirectional Optical Spatial Modulation for Mobile Users: Towards a Practical design for LiFi Systems

Research output: Contribution to journalArticle

Related Edinburgh Organisations

Open Access permissions

Open

Documents

https://ieeexplore.ieee.org/document/8790655/
Original languageEnglish
JournalIEEE Journal on Selected Areas in Communications
DOIs
Publication statusPublished - 7 Aug 2019

Abstract

Among the challenges of realizing the full potential of light-fidelity (LiFi) cellular networks are user mobility, random device orientation and blockage. In the paper, we study the impact of those challenges on the performance of LiFi networks in an indoor environment using measurement-based channel models, unlike existing studies that rely on theoretical channel models. In our work, we adopt spatial modulation (SM) and consider two configurations for the user equipment (UE). A multidirectional receiver (MDR) structure is proposed, in which the PDs are located on different sides of the UE, e.g., a smartphone. This configuration is motivated by the fact that conventional structures exhibit poor performance in the presence of random device orientation and blockage. In fact, we show that MDR outperforms the benchmark structure by over 10 dB at bit-error ratio (BER) of 3:8 × 10..3. Moreover, an adaptive access point (AP) selection scheme for SM is considered where the number of APs are chosen adaptively in an effort to achieve the lowest energy requirement for a target BER and spectral efficiency. The user performance with random orientation and blockage in the entire room is evaluated for sitting and walking activities, for which the orientation-based random waypoint (ORWP) mobility model is invoked. We further demonstrate that the proposed adaptive technique with SM outperforms the conventional spatial multiplexing system. We also study the performance of the underlying system on the uplink channel where we apply the same techniques used for the downlink channel. It is shown analytically that the multi-directional transmitter (MDT) with adaptive SM is highly energy efficient.

Download statistics

No data available

ID: 106642574