Patent ID: 7099589
Filing Date: 2006-08-29
Classification: H04B

Abstract:
1. A base station for use in a space-division multiplex optical wireless local area network for simultaneously interconnecting more than one of a plurality of terminals associated with the wireless local area network to at least one other terminal associated with the wireless local area network, the base station comprising: an angle diversity receiver; and a multi-beam transmitter for outputting a plurality of beams carrying output information from said angle diversity receiver, wherein the multi-beam transmitter includes a plurality of optical transmitters so as to form a plurality of different space cells each having a predetermined size respectively associated with corresponding ones of said beams, and each of the plurality of optical transmitters includes at least one LD or at least one LED as a light source; wherein said angle-diversity receiver includes a plurality of receiving elements separately associated with each respective one of said different space cells, and at least one of the plurality of receiving elements is positioned to receive input from each of said more than one of a plurality of terminals associated with the wireless local area network and wherein, in the multi-beam transmitter, directional half value angles φ of each light source of each of the plurality of optical transmitters are set to specific angles different from each other, the directional half angles being represented by φ=C×θ where C is a constant in the range from 0.70 to 1.00, and θ is an angle of each of the plurality of space cells each having a predetermined size.