title: A 300-MHz digitally compensated SAW oscillator.
abstract: A method for compensating for the inherent temperature sensitivity of surface-acoustic-wave (SAW) oscillators is described. Results for a 300-MHz digitally compensated SAW oscillator (DCSO) show a reduction of temperature-induced frequency variation from +/-125 parts per million to +/-1.4 parts per million over the temperature range of -23 to 75 degrees C. This is accomplished using simple digital circuitry and microprocessor control. The temperature-sensing scheme, using a SAW structure with two delay paths of different temperature sensitivity on the same AT-cut quartz substrate, virtually eliminates thermal resistance and time-constant problems. Advantages over ovenized systems include fast warmup; reduced size, weight, and power dissipation; low cost potential; and the ability to compensate for other sources of frequency drift.
authors.affiliation: Rome Air Dev. Center, Hanscom AFB, MA.
authors.forename: W D
authors.initials: WD
authors.lastname: Cowan
authors.forename: A R
authors.initials: AR
authors.lastname: Slobodnik
authors.forename: G A
authors.initials: GA
authors.lastname: Roberts
authors.forename: J H
authors.initials: JH
authors.lastname: Silva