Patent
Frequency stabilized microwave signal source
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TLDR
In this article, the frequency of a microwave oscillator is stabilized by coupling a portion of the RF signal therefrom to an HF oscillator operating at a sub-multiple of the microwave frequency and producing a strong harmonic at the microwave frequencies in order to cause the operation of microwave and HF oscillators to be locked together.Abstract:
The frequency of a microwave oscillator is stabilized by coupling a portion of the RF signal therefrom to an HF oscillator operating at a sub-multiple of the microwave frequency and producing a strong harmonic at the microwave frequency in order to cause the operation of the microwave and HF oscillators to be locked together. The HF signal frequency, which includes any drift in the microwave oscillator frequency, is divided down a specified amount and compared with the frequency of a stable crystal reference oscillator in a comparator. The output of the comparator is a DC error voltage which is proportional to any drift in the frequency of the microwave oscillator. This error voltage is applied to the microwave oscillator to cause the operating frequency thereof to be more nearly constant.read more
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Patent
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Patent
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High power direct transmitter with frequency-shift keying (FSK) modulation
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TL;DR: In this article, a high power direct transmitter with frequency-shift keying (FSK) modulation is proposed, which allows for production of a modulated RF signal at the final stage, thereby eliminating all driving stage power amplification and frequency translation.
References
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Patent
Digital double differential phase-locked loop
TL;DR: In this paper, a first generator provides a reference pulse train having a predetermined reference frequency, and a second generator including a voltage controlled oscillator provides a bit clock having a repetition frequency locked to the repetition frequency of the bits of digital data.
Patent
Frequency modulation signal receiving system
TL;DR: In this paper, the authors proposed a frequency modulation signal receiving system in which frequency variations of the carrier wave or mean frequency of the signal are employed for the re-production of transmitted signals.
Patent
Phase-locked frequency synthesizer with means for restoring stability
TL;DR: In this article, the authors proposed a frequency synthesizer that detects, ahead of the frequency and phase comparator, the absence of an output from the frequency countdown circuitry of the feedback portion of the phase-locked loop.
Patent
Automatic frequency controlled oscillators
TL;DR: Automatic frequency control means for oscillator arrangement of modulatable frequency wherein signals from the oscillator and signals from a reference source are compared in a comparator which produces signals dependent on the frequency difference of the oscillators and the reference at one or other of two outputs, in dependence upon the sense of said difference.