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Time for a Better Receiver: Chip-Scale Atomic Frequency References



John E. Kitching


Atomic clocks and precision timing are at the core of almost every aspect of global navigation satellite systems (GNSS). A GNSS receiver determines its position with respect to a subset of the constellation of orbiting satellites by measuring the time taken by a radio frequency (RF) signal to travel the distance between the satellite and the receiver. Through a multilateration process, the receiver is able to determine its three spatial coordinates and clock offset from information from a minimum of four satellite signals. Nanosecond-level timing is typically required for positioning with a precision of 1 meter.
GPS World


atomic clock, chip-scale atomic clock, compact frequency reference, CSAC, micromachining


Kitching, J. (2007), Time for a Better Receiver: Chip-Scale Atomic Frequency References, GPS World, [online], (Accessed May 18, 2024)


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Created November 1, 2007, Updated February 17, 2017