Hub architecture for infra-red wireless networks in office environments

Author

Bellon, J. ; Sibley, M.J.N. ; Wisely, D.R. ; Greaves, S.D.

Author_Institution

Dept. of Electr. & Electron. Eng., Huddersfield Univ., UK

Volume

146

Issue

2

fYear

1999

fDate

8/1/1999 12:00:00 AM

Firstpage

78

Lastpage

82

Abstract

The paper describes a LOS system architecture that allows for a data rate of 155 Mbit/s on both down- and up-links. To achieve this, arrays of vertical cavity surface emitting lasers (VCSELs) are used that emit light of 850 nm and have an output power that is within eye-safety limits. Original theory is presented that permits calculation of the coverage area for a certain launch power and receiver sensitivity. Design equations are presented for the selection of the beam shaping/spreading lens placed in front of the laser arrays. Original results from an experimental testbed compare favorably with theoretical predictions. It is concluded that an 8×8 laser array will cover an area of 1 m by 1 m. The addition of a tracking system would permit multiuser operation with each individual user having access to the full bandwidth of the link

Keywords

optical fibre networks; optical receivers; semiconductor laser arrays; sensitivity; surface emitting lasers; 1 m; 155 Mbit/s; 850 nm; IR wireless networks; LOS system architecture; VCSEL arrays; beam shaping; data rate; down-links; eye-safety limits; hub architecture; individual user full bandwidth access; launch power; line of sight system; multiuser operation; office environments; output power; receiver sensitivity; spreading lens; tracking system; up-links; vertical cavity surface emitting lasers;

fLanguage

English

Journal_Title

Optoelectronics, IEE Proceedings -

Publisher

iet

ISSN

1350-2433

Type

jour

DOI

10.1049/ip-opt:19990313

Filename

788753