Oscillators – Automatic frequency stabilization using a phase or frequency... – Plural a.f.s. for a single oscillator
Patent
1977-01-05
1977-07-05
Kominski, John
Oscillators
Automatic frequency stabilization using a phase or frequency...
Plural a.f.s. for a single oscillator
331 1A, 331 10, 331 16, H03B 304
Patent
active
040343103
ABSTRACT:
In a typical phase-locked loop oscillator circuit including a voltage controlled oscillator and a reference frequency source, from each of which a signal is derived and the phases of these two signals are compared in a phase detector, the output of which is applied through a loop filter to a frequency modulation input of the voltage controlled oscillator, so that the frequency of the voltage controlled oscillator is precisely controlled by the reference frequency; an improvement which comprises a maximum phase error detector which determines a maximum permitted phase error between the two inputs to the phase detector, and a phase error corrector circuit which, in response to the presence of a maximum permitted phase error, will shift the phase of one of the two signals applied to the phase detector relative to the source of that signal, such as to hold the phase error into the phase detector within the permitted maximum. This causes the voltage controlled oscillator to shift its frequency to the lock-up frequency in a smooth and steady manner. The improvement prevents operation of the system from being disrupted when the circuit falls out of lock, such as when the modulating signal has large low frequency components. The circuit also includes an out-of-lock detector which responds essentially instantaneously to an in-lock and out-of-lock condition and a means for altering the characteristics of the loop filter in order to minimize the effect of the out-of-lock condition upon the voltage controlled oscillator.
REFERENCES:
patent: 3063021 (1962-11-01), Farrow
patent: 3909735 (1975-09-01), Anderson et al.
LandOfFree
Phase-locked loop oscillator does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Phase-locked loop oscillator, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Phase-locked loop oscillator will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-580378