Interstate Electronics Corporation

L3harris Interstate Electronics Corporation

David Duane Chapman

Steven B Alexander

Apparatus and methods permit the use of a microelectromechanical systems (MEMS) oscillator in a satellite positioning system receiver, such as a Global Positioning System (GPS) receiver. Techniques to ameliorate jitter or phase noise disadvantages associated with MEMS oscillators are disclosed. For example, a receiver can use one or more of the following techniques: (a) use another source of information to retrieve ephemeris information, (2) perform advanced tight coupling, and/or (3) use a phase-locked loop to clean up the jitter or phase noise of the MEMS oscillator. With respect to advanced tight coupling, an advanced tight coupling processor can include nonlinear discriminators which transform I and Q data into linear residual measurements corrupted by unbiased, additive, and white noise. It also includes an amplitude estimator configured to operate in rapidly changing, high power noise; a measurement noise variance estimator; and a linear residual smoothing filter for input to the navigation filter.

Satellite positioning system receivers with microelectromechanical systems oscillators

A radio receiver has a front end having a shared amplification path for both radio frequency signals and intermediate frequency signals. In one example, the shared amplification path can include a low noise amplifier and an attenuator. By amplifying both radio frequency (RF) signals and intermediate frequency (IF) signals with the same shared amplification path, gains in power efficiency, and reductions in cost and circuit size can be achieved.

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Fountain Valley, CA, United States of America

David Duane Chapman