Optical signal processing for indoor positioning using a-SiCH technology

Abstract

In this paper, we use the nonlinear property of SiC multilayer devices under UV irradiation to design an optical processor for indoor positioning. The transducer combines the simultaneous demultiplexing operation with the photodetection and self-amplification. The proposed coding is based on SiC technology. Based on that, we present a way to achieve indoor localization using the parity bits and a navigation syndrome. A representation with a 4 bit original string colour message and the transmitted 7 bit string, the encoding and decoding accurate positional information processes and the design of SiC navigation syndrome generators are discussed and tested. A visible multilateration method estimates the position of the device by using the decoded information received from several, non-collinear transmitters. The location and motion information is found by mapping position and estimates the location areas. Since the indoor position of the LED light source is known from building floor plans and lighting plans, the corresponding indoor position and travel direction of a mobile device can be determined.

Leveraging visible light communication for enhanced indoor wayfinding in unfamiliar buildings

“…This work is focused on the use of a dedicated LED lighting infrastructure to provide accurate indoor positioning based on VLC. We propose the use of a multilayered aSiC-H [16] device to perform the photodetection of the optical signals generated by white trichromatic RGB LEDs [17]. The photodetector operates in the visible range and presents a tunable wavelength sensitivity through external steady-state light illumination [18].…”

On-off keying and Manchester coding in a visible light communication link

“…This system uses white tetrachromatic LEDs to generate optical signals that are detected by an a:SiC:H pinpin heterostructure [7,8,9] operating in the visible range. Designed to address wavelength sensitive devices, it exhibits active filtering, amplification, and selective sensitivity [10,11].…”

“…Designed to address wavelength sensitive devices, it exhibits active filtering, amplification, and selective sensitivity [10,11]. Different visible signals are encoded in the same optical transmission path, so the device multiplexes the different optical channels, performs filtering processes (amplification, switching, and wavelength conversion), and outputs a multiplexed signal [12,13]. The modulated signal transmitted by each emitter can be recovered by decoding this signal [14,15].…”