Raytheon Company

Jeff M Horslund

Kenneth S Barron

Bernard J Gil

Jonathan R Hooker

Christopher D Collinvitti

A global positioning system receiver with a system and method for parallel synchronization. The novel receiver includes a correlator having plural demodulator channels for receiving a signal from a first satellite, and a processor for processing the signal from the first satellite using a plurality of the channels. The processor includes a parallel synchronization process for synchronizing the receiver with the signal. In an illustrative embodiment, the processor is adapted to instruct the plurality of channels to track the signal from the first satellite in parallel, each channel using a different timing hypothesis. Only the channel determined to have the correct timing is retained for tracking the satellite. For the first satellite only, the processor also demodulates the hand-over word and determines a GPS transmit time. The parallel synchronization process is then repeated for subsequent satellites in turn.

Global positioning receiver with system and method for parallel synchronization for reducing time to first navigation fix

A low power GPS tracking system. The novel system includes a first circuit adapted to collect samples of a signal for a first predetermined length of time and in accordance therewith generate an output signal, and a second circuit for cyclically powering on the first circuit for the first predetermined length of time and powering off the first circuit, or a portion thereof, for a second predetermined length of time. In an illustrative embodiment, the first circuit includes a receiver adapted to receive a GPS signal and output GPS data samples, and a processor adapted to calculate a navigation solution from the GPS data samples using an integrate and dump signal processing technique.

Low power dissipation tracking architecture for GPS navigation systems

A system and method for increasing jamming immunity in a GPS/INS system. The system includes a signal processor for receiving and down-converting GPS signals to a baseband frequency to provide I and Q (sine and cosine) signals. An integrate and dump operation is performed on the I and Q signals to provide GPS range and range rate residuals which are uncorrelated from sample to sample. A Kalman filter estimates navigation state corrections from the GPS range and range rate residuals. A NAV function, responsive to the output of the Kalman filter and range error and velocity error signals, provides guidance information and signals for correcting at least one of earth centered earth fixed (ECEF) position, velocity, initial attitude and IMU alignment states which are dynamically calculated from the range and range rate measurements. A line of sight geometry function maps position and velocity vector information from the NAV function into geometric range and range rate scalar information and feeds the scalar information to the signal processor and circuitry to perform an integrate and dump operation.

Growing community of inventors

Tucson, AZ, United States of America

Jeff M Horslund