A technique for providing a location estimate of a mobile station, with increased accuracy. An unenhanced estimate of the location of a target mobile station is first obtained. A portable transmitter is then situated in an initial geographic area defined by the unenhanced estimate. The transmitter is then tuned to transmit a particular identifier on a particular frequency. When the transmitter is moved close enough to the mobile, the mobile starts reporting the identifier to the mobile's wireless network. Because the identifier and frequency are carefully selected so as not into interfere with ongoing operations of the wireless network, the wireless network itself merely regards the reported data to be invalid for handoff purposes. The estimated distance from the transmitter to the mobile depends on the transmit signal strength used by the transmitter. By considering these details, an enhanced estimate of the location of the mobile can then be deduced.