Frequency drift

About: Frequency drift is a research topic. Over the lifetime, 5054 publications have been published within this topic receiving 56191 citations. The topic is also known as: chirp rate.

Digital frequency/phase locked loop

Abstract: A frequency/phase locked loop for providing signals which are frequency and phase locked to signals at a reference frequency from a reference oscillator which is determinative of the frequency stability includes a frequency-controlled generator of a lower frequency stability. The frequency controlled generator is responsive to control signals for switching between first and second frequencies which are substantially higher than the reference frequency. The second frequency is approximately one to ten percent higher than the first frequency. The frequency divider coupled to the frequency generator provides an output signal at the same frequency as the reference oscillator. A digital phase comparator compares the outputs of the frequency divider with the reference signals. A digital integrating stage coupled to the comparator provides the control signals such that during a first portion of a period of the reference signals the first frequency is selected and during a second portion of the period the second frequency is selected.

Integrated circuit frequency generator

Abstract: An integrated circuit frequency generator is disclosed In some embodiments, the frequency generator comprises an electronic oscillator configured to generate an oscillator frequency and calibration circuitry configured to periodically calibrate the electronic oscillator with respect to a reference frequency source When a primary power source is unavailable, an output frequency is generated from the oscillator frequency, and the reference frequency source is powered-on only during calibration cycles

Switching regulator in which oscillation is maintained below a predetermined frequency

Abstract: A switching regulator, which applies output DC voltage to a load via an oscillator oscillatable between ON and OFF states, has an oscillation controller to control the oscillation of the oscillator based on the load so that a frequency of the oscillating of the oscillator is kept lower than a predetermined frequency irrespective of the load.

Phase-locked loop with memory storing control data controlling the oscillation frequency

Abstract: A phase-locked loop with memory storing control data. The control data to be given to a voltage-controlled oscillator in a phase-locked loop is addressed in accordance with an oscillation condition including the frequency of a reference signal, a dividing ratio of the frequency divider and ambient air temperature. When the phase-locked loop is controlled off, the control voltage for the voltage-controlled oscillator is changed into digital data by an analog-to-digital converter to be transferred to the memory. The digital data or control data is read out from the memory when the phase-locked loop is controlled on. The control data is then changed into analog equivalent as control voltage supplied to the voltage-controlled oscillator, shortening the locking-up time.

Center offset microwave frequency synthesizer

Abstract: An improved microwave frequency signal source using a single frequency offset technique which increases the frequency range of an indirect frequency synthesizer to twice the highest operating frequency of the programmable digital frequency divider in the loop includes a voltage-controlled oscillator (VCO) operating within a predetermined microwave frequency band and phase-locked to a reference oscillator operating at a reference frequency below microwave frequencies. The offset loop signal is developed by heterodyning the voltage-controlled oscillator (VCO) output signal with a microwave signal whose frequency is located at the center of the predetermined microwave frequency band of the VCO to form a signal at an intermediate frequency (I.F.) within the frequency range of a programmable digital frequency divider.