Uplink design in VLC systems with IR sources and beam steering

Abstract

The need for high-speed local area networks to meet the recent developments in multimedia and video transmission applications has recently focused interest on visible light communication (VLC) systems. Although VLC systems provide lighting and communications simultaneously from light emitting diodes, LEDs, the uplink channel design in such a system is a challenging task. In this paper, we propose a solution in which the uplink challenge in indoor VLC is resolved by the use of an Infrared (IR) link. We introduce a novel fast adaptive beam steering IR system (FABS-IR) to improve the uplink performance at high data rates while providing security for applications. The goal of our proposed system is to enhance the received optical power signal, speed up the adaptation process and mitigate the channel delay spread when the system operates at a high transmission rate. The channel delay spread is minimised from 0.22 ns given by hybrid diffuse IR link to almost 0.07 ns. At 2.5 Gb/s, our results show that the imaging FABS-IR system accomplished about 11.7 dB signal to noise ratio (SNR) in the presence of multipath dispersion, receiver noise and transmitter mobility.Index Terms-uplink channel, beam steering IR, delay spread, SNR.

Networked multiple-input-multiple-output for optical wireless communication systems

“…How to decouple the multiple data streams is discussed in the next section. Frequency division duplexing is generally adopted in OWC networks, where an RF or infrared frequency band is used for uplink and a visible light frequency band is used for downlink [24,25]. Therefore, downlink channel estimation and uplink feedback is required if APs need CSI [26].…”

CGH for Indoor Visible Light Communication System

“…4) The user transceiver sends (using an IR beam) a low data rate control feedback signal to inform the controller of the SNR associated with the first RYGB LDs-light unit. The design of IR uplink has been investigated in [40]. 5) Repeat steps 2 to 4 for other RYGB LDs-light units.…”

Optimum Resource Allocation in 6G Optical Wireless Communication Systems

“…OWC data rates exceeding 25 Gbps per user have been demonstrated in downlink communication in indoor settings [9] - [20]. The uplink has been studied in different works [21], [22], also, energy efficiency is an area that must be given an attention [23]. In addition, various configurations of transmitter and receiver have been studied to reduce the delay spread [15], [24] - [31]while increasing the signal-to-noise ratio (SNR) [32] - [36].…”