Patent ID: 6091362
Filing Date: 2000-07-18
Classification: G01S,H04W,Y02D

Abstract:
A wireless location system for estimating the geographic location of a mobile transmitter, wherein said mobile transmitter is operative to transmit narrowband signals at frequencies spanning a predefined wide band of frequencies, and wherein said predefined wide band of frequencies is wider than the bandwidth of the individual narrowband signals transmitted by said mobile transmitter, comprising:(a) at least three geographically separated receivers for receiving the narrowband signals transmitted by said mobile transmitter;(b) bandwidth synthesis means for effecting the transmission by said mobile transmitter of narrowband signals at a plurality of frequencies spanning said predefined wide band of frequencies;(c) means for resolving integer cycle ambiguity in phase relationships between the plurality of transmitted narrowband signals; and(d) time difference of arrival means for determining the location of said mobile transmitter using the plurality of narrowband signals.