Patent ID: 7388541
Filing Date: 2008-06-17
Classification: G01C,G01S

Abstract:
1. In a self-calibrating position location system utilizing a plurality of transmitters that broadcast digital multimedia signals, a method of obtaining a position solution for a user receiver, comprising the steps of: receiving broadcast digital transmissions from at least some of said transmitters, wherein each of said broadcast digital transmissions embeds at least one known periodic code, and wherein each of said transmitters has a transmitter phase center; providing a user receiver that generates a time base; determining a measured time of arrival of said known periodic code at said user receiver relative to said time base of said user receiver; estimating a phase center of said antenna of said user receiver, therein producing a receiver phase center; calculating, at said user receiver, self-calibrating time offsets from said transmitter phase center and said receiver phase center calculating a predicted time of arrival of said known periodic code for said transmitters based on said self-calibrating time offsets; and determining a position of said user receiver based on said measured time of arrival and said predicted time of arrival of each of said transmitters.