Lucent Technologies Inc.

Ibrahim Tekin

Byron H Chen

Tung Ching Chiang

Ren Da

Giovanni Vannucci

Robert Ellis Richton

A method and apparatus for facilitating detection of satellite signals using a dynamic integration technique in which integration time periods of correlators are adjusted according to signal strength measurements of satellite signals received at GPS receivers. Specifically, integration time periods are inversely adjusted, either proportionally or non-proportionally, to received strengths of signals being searched.

Satellite-based location system employing dynamic integration techniques

A method and apparatus for estimating the location of a mobile terminal. The method estimates the locations by: a) using at least one forward-link geo-location technique without using any reverse-link geo-location techniques, this being performed when there are enough base stations visible to the mobile terminal to be able to use the forward-link geo-location technique without using any reverse-link geo-location techniques to estimate the location, and b) using at least one reverse-link geo-location technique when there are not enough base stations visible to the mobile terminal to be able to use the forward-link geo-location technique without also concurrently using any reverse-link geo-location techniques to estimate the location. The forward-link geo-location techniques can be used either alone or in combination with each other, and include such known geo-location techniques as a time-difference-of-arrival technique and angle-difference-of-arrival technique. Illustratively, when the predetermined number, for example three, base stations are visible to the mobile terminal, the location of the mobile terminal is estimated using time-difference-of-arrival. When fewer than three base stations are visible to the mobile terminal, the location of the mobile terminal is estimated using round trip delay. Estimating the location of a mobile terminal by using only forward-link geo-location techniques when there are enough base stations visible to the mobile terminals to be able to use forward-link geo-location techniques, produces a more accurate estimation of the mobile terminal's location. It also allows wireless assisted GPS (AGPS) systems to more quickly estimate a more precise location of the mobile terminal.

Method and apparatus for estimating the location of a mobile terminal

Weighted ridge regression (WRR) processing is applied to three or more distance measurements to determine the location of a terminal. For example, in an integrated satellite-based navigation system/wireless network, the location of a mobile unit can be determined by applying WRR processing to at least three distance measurements, where one or more of the distance measurements are satellite-based distance measurements (e.g., GPS pseudorange measurements) and one or more are wireless network-based distance measurements (e.g., round-trip delay or pilot phase offset measurements). WRR processing provides improved accuracy in the determination of mobile unit position over conventional least mean square techniques.

Location determination using weighted ridge regression

A location or position of a wireless mobile unit is determined using only measurements from a single base station. A distance between the wireless mobile unit and the base station is calculated utilizing a roundtrip delay value of an RF uplink signal received from a wireless mobile unit. Thereafter, an angle of arrival of the received signal is determined using measurements of the received signal from each of a plurality of antenna sectors of a multi-sector antenna. The angle of arrival is determined based upon stored antenna signal measurements of the multi-sector antenna, wherein a combination of different sector signal measurements corresponds to a single angle measurement. Using the determined distance and angle of arrival, a position or location of a wireless mobile unit can easily be determined using only measurements of the single base station.

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Summit, NJ, United States of America

Ibrahim Tekin