Augmentation of commercial Wireless Location System (WLS) with moving and/or airborne sensors for enhanced location accuracy and use of real-time overhead imagery for identification of wireless device locations

摘要

Mobile LMUs can be used in a Wireless Location System to provide detection coverage in areas lacking adequate receiver coverage. The mobile LMUs can be used to detect the radio frequency (RF) transmissions from wireless handsets and devices over a period of time to permit determination of their location. The mobile LMU' s time, position, and velocity is calculated and transmitted to a SMLC along with any transmissions received from wireless devices. The SMLC analyzes and resolves the Doppler component of the wireless device while compensating for the Doppler component of the mobile LMU. The position and velocity of the wireless device can be compared with real-time imagery taken by the mobile LMU platform to accurately determine the location of the wireless device. To enhance the mobile LMU' s ability to detect a signal of interest, which may be very weak and/or corrupted by noise, a process may be employed whereby the low power mobile terminals' signals are received at receiving sitesand stored in memory. Then, a more powerful replica of the SOI is received at a later time from a network controller, or BTS, and this is employed to enhance the correlation processing of the SOI inmemory.