Oscillators – Automatic frequency stabilization using a phase or frequency... – Afc with logic elements
Patent
1995-04-19
1996-10-22
Grimm, Siegfried H.
Oscillators
Automatic frequency stabilization using a phase or frequency...
Afc with logic elements
331105, 331175, 332123, H03C 300, H03L 702
Patent
active
055680968
ABSTRACT:
An apparatus and method are provided for increasing the effective Q-value of an oscillator so that the required Q-value can be reached with the use of a low Q-value oscillator. In this apparatus and method, the FM noise is measured at the output of the oscillator by an FM detector and the output of the FM detector is fed back to the control input of the oscillator. By using this negative FM feedback, frequency variations in the oscillator output are suppressed by applying a correction signal at the control input of the oscillator. The amount of suppression depends on the loop gain of the FM feedback loop and the amount of suppression is proportional to the loop gain so that the effective Q-value of the oscillator is proportional to the loop gain. As a result of correcting the FM noise measured at the oscillator output by using a negative FM feedback loop, the effective Q-value of the oscillator corresponds to the original Q-value multiplied by the loop gain of the FM feedback loop so that the effective Q-value of the oscillator is increased.
REFERENCES:
patent: 4661785 (1987-04-01), Benjaminson
patent: 4788512 (1988-11-01), Hogge, Jr. et al.
patent: 4792768 (1988-12-01), Fried et al.
patent: 5170130 (1992-12-01), Ichihara
patent: 5220292 (1993-06-01), Bianchini et al.
patent: 5272452 (1993-12-01), Adachi et al.
patent: 5311149 (1994-05-01), Wagner et al.
patent: 5331293 (1994-07-01), Shepherd et al.
patent: 5345193 (1994-09-01), Bradley
H. Taub et al., "Threshold in Frequency Modulation", Principles of Communication Systems, Chap. 10, 1986, pp. 394-440; McGraw-Hill, N.Y.
A. G. van Nie, "Short-Term Stability of Harmonic Oscillators", Philips Res. Repts., 25, 1970, pp. 437-451.
A. Bruce Carlson, "Communication Systems: An Introduction to Signals and Noise in Electrical Communication", p. 270, 1986, McGraw-Hill, N.Y.
Patent Abstracts of Japan, vol. 13, No. 62 (E-715), Feb. 1989 (JP-A-63 252003 Oct. 1988).
Grimm Siegfried H.
Telefonaktiebolaget LM Ericsson
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