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.

Radio frequency standard and voltage controlled oscillator

Abstract: A radio signal controlled oscillator is provided as a local frequency standard by synchronizing the oscillator using a phaselock servosystem comprising a long term integrating device as a voltage variable capacitor in the resonant circuit of the oscillator. The device consists of two columns of mercury separated by a substantial gap of electrolyte in a chamber made of dielectric material. Upon comparison of the oscillator signal with the radio signal, any error signal developed is applied across the electrolyte gap to the mercury column to transfer mercury from one to the other by the process of electrolysis. Conductive material wrapped around the chamber serves as a second plate of a capacitor for each of the columns one of which is used as part of the voltage variable capacitor. Means is provided for detecting the loss of the radio signal to interrupt any further change in the variable capacitor until the radio signal is restored.

A laser setup for rubidium cooling dedicated to space applications

Abstract: We present the complete characterization of a laser setup for rubidium cooling dedicated to space applications. The experimental setup is realized with commercial off-the-shelf fiber components suitable for space applications. By frequency doubling two fiber laser diodes at 1560 nm, we produce the two optical frequencies at 780 nm required for atomic cooling of 87Rb. The first laser is locked on saturated absorption signal and long-term frequency drift has been canceled using a digital integrator. The optical frequency of the second laser is controlled relatively to the first one by a frequency comparison method. A full characterization of the setup, including frequency stability evaluation and frequency noise measurement, has been performed. The optical frequency doubling module has been submitted to environmental tests to verify its compatibility with space applications.

Low-Voltage Low-Power CMOS Oscillator with Low Temperature and Process Sensitivity

Abstract: The design of an on-chip RC-based oscillator, implemented in a standard 0.35 mum CMOS process, without any external component, is presented. The proposed oscillator provides a clock signal at a frequency of about 80 KHz with a temperature coefficient smaller than 842 ppm/degC over a temperature range from 0 to 80 7degC and a standard deviation due to process variations smaller than 4%, without any external trimming. The proposed oscillator operates with a supply voltage of 1 V and has a power consumption of about 1 muW at room temperature. The chip area is 0.24 mm2.

Ring oscillator having a substantially sinusoidal signal

Abstract: A ring oscillator comprising an odd number of inverters connected in a ring, and apparatus for driving the ring oscillator so that it oscillates at a frequency slightly less than its maximum oscillating frequency such that harmonics of the oscillating frequency are suppressed.

DC-DC regulator with switching frequency responsive to load

Abstract: A switch mode power supply in which the switching frequency is controlled by an oscillator having a nominal frequency, and having an error amplifier to provide an output signal which represents departure of the power supply output from a nominal value, and which functions by adjusting the frequency of the oscillator to a frequency which is higher or lower than the nominal frequency according to the value of the error amplifier output signal.