Accession Number : ADD012282

Title :   Low Noise Multiple Crystal-Controlled Oscillator.

Descriptive Note : Patent,

Corporate Author : DEPARTMENT OF THE AIR FORCE WASHINGTON DC

Personal Author(s) : Driscoll,Michael M

Report Date : 11 Feb 1986

Pagination or Media Count : 9

Abstract : An oscillator circuit utilizing multiple (two) quartz crystal resonators as the frequency controlling elements in a novel circuit arrangement. The use of two crystal units increases the oscillator circuit signal transmission group delay by a factor of 2 to 3 and effects an estimated 6 dB reduction in oscillator output signal phase noise sideband level at carrier offset frequencies less than the resonator half-bandwidths. The degree of resonator tracking required is made practical with the use of temperature controlled SC-cut resonators. In addition, the oscillator circuit is configured so that equal, correlated output signal currents can be extracted from each resonator through individual load circuits, thereby increasing available oscillator output signal amplitude by 2:1 and reducing the net effect of uncorrelated load circuit additive noise by 3 dB. (Author)

Descriptors :   *PATENTS, *QUARTZ RESONATORS, *FREQUENCY STABILIZERS, *LOCAL OSCILLATORS, *NOISE REDUCTION, *SINGLE CRYSTALS, THERMAL STABILITY, MATCHED FILTERS, CARRIER FREQUENCIES, WHITE NOISE, NARROWBAND, PHASE SHIFT, RESONATORS, CIRCUITS, OUTPUT, SIGNALS, QUARTZ, TRACKING, CURRENTS, AMPLITUDE, OSCILLATORS

Subject Categories : Electrical and Electronic Equipment
      Cybernetics
      Crystallography

Distribution Statement : APPROVED FOR PUBLIC RELEASE