Performance comparison of LSMS and conventional diffuse and hybrid optical wireless techniques in a real indoor environment

Performance evaluations were carried out for indoor optical wireless systems in three different environments. Channel characteristics of infrared links have been evaluated under various conditions including an empty room, a room with glass windows and a door, and a room that has very strong shadowing effects caused by mini cubical offices. The corresponding results have been analysed and compared for conventional diffuse/hybrid systems (CDS/CHS) and line strip multibeam transmitter systems (LSMS) that use spot diffusing techniques. Eight directive lamps represented the ambient light noise and allowed further signal impairments to be taken into account. Under these conditions, results indicate that LSMS can reduce pulse spread by factors of 11 and 24 compared to the maximum delay spread associated with CDS and CHS respectively. Furthermore, LSMS links can increase the SNR by more than 50 dB compared to the CDS and CHS.

[1]  Edward A. Lee,et al.  Simulation of Multipath Impulse Response for Indoor Wireless Optical Channels , 1993, IEEE J. Sel. Areas Commun..

[2]  Jaafar M. H. Elmirghani,et al.  Performance of optical wireless OOK and PPM systems under the constraints of ambient noise and multipath dispersion , 1998 .

[3]  Jaafar M. H. Elmirghani,et al.  Analysis of Optical Wireless Systems based on Line Strip Multibeam Transmitters and Diversity Detection , 2002 .

[4]  Joseph M. Kahn,et al.  Wireless Infrared Communications , 1994 .

[5]  D. R. Wisely,et al.  Optical wireless: the story so far , 1998, IEEE Commun. Mag..

[6]  John R. Barry,et al.  Non-directed infrared links for high-capacity wireless LANs , 1994, IEEE Personal Communications.

[7]  M. Kavehard,et al.  Multispot diffusing configuration for wireless infrared access , 2000, IEEE Trans. Commun..

[8]  Jaafar M. H. Elmirghani,et al.  Performance evaluation of a triangular pyramidal fly-eye diversity detector for optical wireless communications , 2003, IEEE Commun. Mag..

[9]  Jaafar M. H. Elmirghani,et al.  Line strip spot-diffusing transmitter configuration for optical wireless systems influenced by background noise and multipath dispersion , 2004, IEEE Transactions on Communications.

[10]  Anthony C. Boucouvalas,et al.  Indoor ambient light noise and its effect on wireless optical links , 1996 .

[11]  Jaafar M. H. Elmirghani,et al.  Sensitivity evaluation of optical wireless PPM systems utilising PIN-BJT receivers , 1996 .

[12]  Mohsen Kavehrad,et al.  Spot-diffusing and fly-eye receivers for indoor infrared wireless communications , 1992, 1992 IEEE International Conference on Selected Topics in Wireless Communications.

[13]  U. Bapst,et al.  Wireless in-house data communication via diffuse infrared radiation , 1979 .

[14]  Jaafar M. H. Elmirghani,et al.  Optimization of a triangular PFDR antenna in a fully diffuse OW system influenced by background noise and multipath propagation , 2003, IEEE Trans. Commun..

[15]  Mohsen Kavehrad,et al.  Indoor Wireless Infrared Link with a Holographic Multiple-Spot Diffuser , 1997 .