We present a study on evaluating the effects of multipath dispersion on indoor optical code division multiple access (CDMA) systems over optical wireless communication. The indoor propagation channel model which takes multiple reflecting surfaces into account is addressed. Theoretical analysis of the pulse response of direct light and reflected light is given. The bit error rate (BER) of this system is analyzed considering reflected light, background light, avalanche photo-diode noise, thermal noise, and multi-user interference. The results prove that the BER of the system is influenced by reflected light and that the effect of reflected light is related to room size and receiver position. With an increase in the number of users, the effect of reflected light becomes stronger and is a significant source of inter-symbol interference. It becomes clear that when optical CDMA is used in an indoor optical wireless system, the effect of reflected light is a key issue to be considered.
© 2012 OSA
Original Manuscript: August 11, 2011
Revised Manuscript: July 26, 2012
Manuscript Accepted: October 5, 2012
Published: November 20, 2012
Jiang Liu, Zhenni Pan, Wasinee Noonpakdee, and Shigeru Shimamoto, "Impact of Light Reflection on Indoor Wireless Optical CDMA Systems," J. Opt. Commun. Netw. 4, 989-996 (2012)