Abstract
Diffused infrared transmission is one of thepreferred techniques used in indoor wirelesscommunications. Tolerance to shadowing and a lack ofalignment requirements are among the many advantagesoffered by this technique compared to the line-of-sighttechniques. However, it has its disadvantages, namelyhigh path loss and multipath dispersion. The limitationimposed by eye-safety requirements restricts the transmitted power. Therefore, efficient useof transmitted optical power is the key for practicalbroadband infrared systems. In this paper, we report onusing a holographic diffuser for shaping of infrared radiation pattern in an indoorinfrared transmission system. The holographic diffusershave the advantage of light weight and added flexibilityin the system design. The reported measurements show that employing a properly designed holographicdiffuser can reduce the path loss of a nondirectedoptical link. The results also show another advantage ofusing the proposed holographic diffuser, which is additional tolerance of the transmission toshadowing.
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Pakravan, M.R., Simova, E. & Kavehrad, M. Holographic Diffusers for Indoor Infrared Communication Systems. International Journal of Wireless Information Networks 4, 259–274 (1997). https://doi.org/10.1023/A:1018876326494
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DOI: https://doi.org/10.1023/A:1018876326494