Patent ID: 7167713

Claim:
A method for use in a wireless location system (WLS) that estimates the geographic location of a mobile station (MS), wherein the WLS overlays at least a portion of the geographic area of a wireless communications system, wherein the WLS uses radio and location processing resources to locate said MS using a process involving receiving a transmission from the MS at multiple sites and processing the received transmissions to estimate the location of the MS using time difference of arrival (TDOA) and/or angle of arrival (AOA) location processing techniques, comprising: passively monitoring communications between at least one base transceiver station (BTS) and at least one base station controller (BSC) of the wireless communications system; extracting MS information from the monitored communications, said extracted MS information including radio frequency channel information, whereby the WLS is able to receive transmissions from the MS; and using the extracted MS information to trigger location processing and to determine which radio frequency channel to use in performing location processing for said MS.