US 6,204,812 B1 · Methods and apparatus to position a mobile receiver using downlink signals, part II

Abstract

The invention consists of methods and apparatus to estimate the position and velocity of a Mobile Receiver (MR) using either the Time Of Arrival (TOA) of signals received by the MR, their Phase Of Arrival (POA), their Strength Of Arrival (SOA), their Frequency Of Arrival (FOA), or a combination thereof, with respect to a reference produced by a Reference Receiver (RR) of known location. In order to solve for the coordinates of the MR, the invention uses either hyperbolic multilateration based on Time Difference Of Arrival (TDOA), or linear multiangulation based on Phase Difference Of Arrival (PDOA), or both. In order to solve for the velocity of the MR, the patent uses FOA based on Frequency Difference Of Arrival (FDOA). An important contribution of this invention is the way the MR receives, processes and combines available signals for location purposes. Another important contribution of this invention is the way the RR receives, processes and combines available signals for reference purposes.

Claims28

Dependent claims

A system to estimate the location of a mobile receiver, the system comprising:

an IF receiver for receiving a plurality of RF signals ri(t) transmitted by a plurality of base stations, the IF receiver being configured to generate an IF signal, the IF receiver including a local oscillator and an RF synthesizer for controlling the local oscillator;
and
an estimator for estimating the carrier offset due to Doppler, δfi, and due to local oscillator offset, Δfi of the plurality of RF signals ri(t).

Dependencies are inferred from the claim text.

Methods and apparatus to position a mobile receiver using downlink signals, part II

Life of this patent

Methods and apparatus to position a mobile receiver using downlink signals, part II

Life of this patent

Abstract

Claims28