Sri International

Joseph M Strus

David A Watt

Jesse Wodin

Robert H Sparr

Joshua A Arndt

Boskin Erkocevic

Justin D Landrum

James W Sinko

Jacob M Cooper

Systems and methods for clock synchronization are disclosed. A client synchronization system (CSS) may transmit RF pulses to a server CSS over micrometeorite ionization trail (MMIT) channels, and may receive RF pulses from the server CSS over MMIT channels, each received RF pulse following transmitted RF pulse. The client CSS may receive from the server CSS over MMIT channels measurement data including pulse arrival times at the server CSS. The measurement and transmission data may be correlated to identify RF-pulse pairs, each pairing a transmitted RF pulse received by the server CSS with a received RF pulse received from the server CSS, both over the same MMIT. TWTT analysis may be applied to timing data the pairs to compute time offsets between a client clock and a server clock. An analytical model of clock drift may be applied to the offsets to synchronize the client clock to the server clock.

Precision two-way time transfer over meteorburst communications channels

The present invention relates to a method and apparatus for estimating relative position in a global navigation satellite system. In one embodiment, a method for estimating a position of a first receiver relative to a second receiver in a global navigation satellite system includes obtaining a first set of measurements from the first receiver, where the first set of measurements estimates a first distance between the first receiver and a satellite in the global navigation satellite system, obtaining a second set of measurements from the second receiver, where the second set of measurements estimates a second distance between the second receiver and a satellite in the global navigation satellite system, performing time domain recursive filtering in accordance with the first set of measurements and the second set of measurements, and estimating the position of a first receiver relative to a second receiver in accordance with the time domain recursive filtering.

Method and apparatus for estimating relative position in a global navigation satellite system

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Redwood City, CA, United States of America

Joseph M Strus