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Numerical Evaluation SINR of an IR system Jinhui Wang. Introduction. What is Infrared? Why? 700-1600nm Abundance of unregulated bandwidth. No multi-path fading High security Direct Sequence Code Division Multiple Access Low power transmission and reception Security.
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Numerical Evaluation SINR of an IR system Jinhui Wang
Introduction • What is Infrared? Why? • 700-1600nm • Abundance of unregulated bandwidth. • No multi-path fading • High security • Direct Sequence Code Division Multiple Access • Low power transmission and reception • Security
Interference and Noise 1. multi-user interference 2. Multipath dispersion 3. Noise (Background)
Three main sources of ambient light 1. Sun light, produces the highest levels of background current, so it is the major source of shot noise. 2. Incandescent light 3. Fluorescent light Optical Power spectrum for Ambient light noise
Building Noise Model • Very shiny day • Well fluorescent room: 5x6m • Incandescent light: 60W, 1m away • Fluorescent light: 8x36W, 2.2m away • With and without filter
Important Conclusion • DS-CDMA is used in Infrared system. • SINR is calculated on three parts of noise components. • SINR for Exponentially Decay Channel is always better than Linearly Decay Channel. • Optical filter greatly reduces the background current. Higher SINR is achieved. • With larger Code length (N), higher SINR. • As the users increase, SINR decrease.
Reference • [1] Xavier N. Fernando, “Performance of an Infrared Wireless CDMA System” Proceedings of the Digital Wireless Communications Conference V at SPIE's 17th Annual AeroSense Symposium 2003. • [2] Adriano J.C. Noreira, Rui T. Valadas and A.M. de Oliveira Duarte, “ Optical interference produced by artificial light”, Wireless Networks 3 (1997) 131-140 • [3] Moreia A.J.C., Valadas R.T, and de Oliveira Duarte A.M. Optical interference produced by artificial light, Wireless Networks, Vol.3, pp 131-140, 1997.