초록 ▼

In a mobile communication network, the accuracy of location determinations for mobiles based on TDOA measurements made by the mobiles is increased by measuring the TDOA of signals from base station pairs at a known location and generating correction factors for compensating timing and propagation er

In a mobile communication network, the accuracy of location determinations for mobiles based on TDOA measurements made by the mobiles is increased by measuring the TDOA of signals from base station pairs at a known location and generating correction factors for compensating timing and propagation errors in TDOA measurements made by the mobiles. Calibration terminals may be provided for measuring TDOAs at known locations. System processes and elements for applying data generated by calibration terminals are disclosed.

대표청구항 ▼

[ What is claimed is:] [1.]1. A process in a mobile communication network, comprising:determining an expected time difference of arrival (TDOA) at a known location for signals of at least three base station pairs of the network;determining a measured TDOA for each of said base station pairs at said

[ What is claimed is:] [1.]1. A process in a mobile communication network, comprising:determining an expected time difference of arrival (TDOA) at a known location for signals of at least three base station pairs of the network;determining a measured TDOA for each of said base station pairs at said known location;determining an average measured TDOA for each of the base station pairs at said known location for a period of time;determining a correction factor for each base station pair constituting the difference between the expected and average measured TDOAs;determining a measured TDOA at a location of a mobile for each of said base station pairs;for each of said base station pairs, if a TDOA at the location of the mobile differs from a corresponding TDOA at the known location by less than a predetermined amount, applying a corresponding correction factor to said measured TDOA to yield a corrected TDOA; anddetermining a location using said corrected TDOAs.