Patent ID: 6304762
Filing Date: 2001-10-16
Classification: H04W

Abstract:
A point to multipoint communications system comprising:a base station nodal transmitter and base station transmit antenna and a base station receiver system and base station receive antenna system located at each node, said base station transmitter and base station transmit antenna broadcasting signals over a given downstream sector of said node;remote transceiver stations located at the downstream sector of said node capable of receiving said signals from said base station transmitter broadcasting signals over said downstream sector of said node and capable of transmitting polarized return upstream signals to said base station nodal receiver system and base station receive antenna system;said base station nodal receiver system including one or more receivers for each downstream sector for receiving said return upstream signals from said remote stations;said base station nodal receive antenna system including a plurality of offset subsector antennas for said given downstream sector of said node such that the center of the coverage area in said downstream sector of each of the antennas is separated and offset to present different coverage over the downstream sector by the offset subsector antennas and said plurality of offset subsector antennas for each given downstream sector are of orthogonal polarization to the plurality of offset subsector antennas for the adjacent downstream sector such that the polarization of the receive antenna system alternates from sector to sector about the node; andmeans for selectively coupling said offset subsector antennas of said downstream sector of said node to said one or more base station nodal receivers for each downstream sector.