Indoor High-Bandwidth Optical Wireless Links for Sensor Networks

• Published in: Journal of lightwave technology Vol. 28; no. 21; pp. 3086 - 3094
• Main Authors: Fadlullah, J, Kavehrad, M
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.11.2010; Institute of Electrical and Electronics Engineers
• Subjects: Applied sciences; Channel characterization; Detection, estimation, filtering, equalization, prediction; Exact sciences and technology; Frequency measurement; Information, signal and communications theory; infrared; Lenses; Optical scattering; Optical sensors; Optical telecommunications; Optical transmitters; Optical variables measurement; optical wireless communication; quasi-diffuse; Receivers; sensor neworks; Services and terminals of telecommunications; Signal and communications theory; Signal, noise; Systems, networks and services of telecommunications; Telecommunications; Telecommunications and information theory; Telemetry. Remote supervision. Telewarning. Remote control; Transmission and modulation (techniques and equipments); Wireless optical communications; Optical telecommunication; Wireless telecommunication; infrared; Remote sensing; Eavesdropping; quasi-diffuse; Cavity; Indoor installation; Optical bus; Free space optics; Channel characterization; Signal detection; Monitoring; Telecommunication security; Procurement; Multimedia; Optical links; Range finding; Radiofrequency device; optical wireless communication; sensor neworks; Power electronics; Radiofrequency; Avionics; Free space propagation; Aerosols; Power device; Wireless network; Miniaturization; Low-power electronics; Sensor array; Radio communication
• ISSN: 0733-8724; 1558-2213
• DOI: 10.1109/JLT.2010.2076775

Emergence of sensor networks for data-procurement in wide-ranging applications, including defense, medical, environmental and structural health monitoring, has led to development of low-power miniature devices employing radio frequency (RF) communications. In contrast to RF, optical devices are smaller and consume less power; reflection, diffraction, and scattering from aerosols help distribute signal over large areas; and optical wireless provides freedom from interference and eavesdropping within an opaque enclosure. Optics can accommodate high-bandwidth transmission of multimedia in aircrafts, where RF is shunned due to interference with control signals. These motivate use of optical wireless as a mode of communication in sensor networks. We have set up and experimented on an infrared laser transceiver test-bed with ceiling used as reflector to establish an intensity-modulated/direct-detected (IM/DD) link. Frequency measurements are conducted to characterize the link up to 1 GHz, and are transformed to obtain impulse responses and eye diagrams. These experimental findings demonstrate the capability of indoor optical wireless links of delivering 1 gigabit per second and beyond, without intersymbol interference. Thus, a broadband infrastructure can be deployed allowing high-quality audio-visual data communication among sensor nodes.