Title :
Time and frequency applications
Author_Institution :
US Air Force Office of Sci. Res., Bolling AFB, Washington, DC, USA
Abstract :
An overview is given of the capabilities of atomic clocks and quartz crystal oscillators in terms of available precision of time and frequency signals. The generation, comparison, and dissemination of time and frequency is then discussed. The principal focus is to survey uses of time and frequency in navigation, communication, and science. The examples given include the Global Positioning System, a satellite-based global navigation system, and general and dedicated communication networks, as well as experiments in general relativity and radioastronomy. The number of atomic clocks and crystal oscillators that are in actual use worldwide is estimated.<>
Keywords :
atomic clocks; crystal resonators; frequency measurement; measurement standards; oscillators; quartz; time measurement; Global Positioning System; SiO/sub 2/; atomic clocks; dedicated communication networks; quartz crystal oscillators; satellite-based global navigation system; Atomic clocks; Degradation; Frequency; Hydrogen; Instruments; Oscillators; Radio navigation; Resonance; Satellite navigation systems; Signal generators;
Journal_Title :
Ultrasonics, Ferroelectrics, and Frequency Control, IEEE Transactions on
