frequency reference

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• Frequency standard — A frequency standard is a stable oscillator used for frequency calibration or reference. A frequency standard generates a fundamental frequency with a high degree of accuracy and precision. Harmonics of this fundamental frequency are used to… …   Wikipedia

• Frequency counter — A frequency counter is an electronic instrument, or component of one, that is used for measuring frequency. Since frequency is defined as the number of events of a particular sort occurring in a set period of time, measuring it is usually… …   Wikipedia

• Frequency Scanning Interferometry — (FSI) is an absolute distance measurement technique, for measuring the distance between a pair of points, along a line of sight. The power of the FSI technique lies in its ability to make many such distance measurements, simultaneously. For each… …   Wikipedia

• Frequency-dependent selection — is the term given to an evolutionary process where the fitness of a phenotype is dependent on its frequency relative to other phenotypes in a given population. In positive frequency dependent selection (or purifying frequency dependent selection) …   Wikipedia

• Frequency dependent selection — is the term given to an evolutionary process where the fitness of a phenotype is dependent on its frequency relative to other phenotypes in a given population. In positive frequency dependent selection, the fitness of a phenotype increases as it… …   Wikipedia

• Frequency multiplier — A frequency multiplier is commonly used in a radio receiver or radio transmitter to multiply the base frequency of the oscillator by a predetermined number. This multiplied frequency is then amplified and sent to the final drive stage and into… …   Wikipedia

• Frequency synthesizer — A frequency synthesizer is an electronic system for generating any of a range of frequencies from a single fixed timebase or oscillator. They are found in many modern devices, including radio receivers, mobile telephones, radiotelephones, walkie… …   Wikipedia

• Frequency — For other uses, see Frequency (disambiguation). Three cyclically flashing lights, from lowest frequency (top) to highest frequency (bottom). f is the frequency in hertz (Hz), meaning the number of cycles per second. T is the period in seconds (s) …   Wikipedia

• Frequency-locked loop — A frequency lock, or frequency locked loop (FLL), is an electronic control system that generates a signal that is locked to the frequency of an input or reference signal. This circuit compares the frequency of a controlled oscillator to the… …   Wikipedia

• Frequency domain — In electronics, control systems engineering, and statistics, frequency domain is a term used to describe the domain for analysis of mathematical functions or signals with respect to frequency, rather than time.[1] Speaking non technically, a time …   Wikipedia

• Frequency divider — A frequency divider, also called a clock divider or scaler or prescaler, is a circuit that takes an input signal of a frequency, fin, and generates an output signal of a frequency: where n is an integer. Phase locked loop frequency synthesizers… …   Wikipedia