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Antenna gain-to-noise-temperature ( G/T) is a figure of merit in the characterization of antenna performance, where G is the antenna gain in decibels at the receive frequency, and T is the equivalent noise temperature of the receiving system in kelvins. The receiving system noise temperature is the summation of the antenna noise temperature and ...
In electronics, noise is an unwanted disturbance in an electrical signal. [ 1]: 5. Noise generated by electronic devices varies greatly as it is produced by several different effects. In particular, noise is inherent in physics and central to thermodynamics. Any conductor with electrical resistance will generate thermal noise inherently.
Johnson 's 1927 experiment showed that if thermal noise from a resistance of with temperature is bandlimited to bandwidth , then its root mean squared voltage is in general, where is the Boltzmann constant. Johnson–Nyquist noise ( thermal noise, Johnson noise, or Nyquist noise) is the electronic noise generated by the thermal agitation of the ...
Dynamic range (abbreviated DR, DNR, [ 1] or DYR[ 2]) is the ratio between the largest and smallest values that a certain quantity can assume. It is often used in the context of signals, like sound and light. It is measured either as a ratio or as a base-10 ( decibel) or base-2 (doublings, bits or stops) logarithmic value of the ratio between ...
Noise temperature (antenna) In radio frequency (RF) applications such as radio, radar and telecommunications, noise temperature of an antenna is a measure of the noise power density contributed by the antenna to the overall RF receiver system. It is defined as "the temperature of a resistor having an available thermal noise power per unit ...
Thermoacoustics is the interaction between temperature, density and pressure variations of acoustic waves. Thermoacoustic heat engines can readily be driven using solar energy or waste heat and they can be controlled using proportional control. They can use heat available at low temperatures which makes it ideal for heat recovery and low power ...
Noise floor. Measurement from a spectrum analyzer showing a noise-like measurement from an unspecified component. In signal theory, the noise floor is the measure of the signal created from the sum of all the noise sources and unwanted signals within a measurement system, where noise is defined as any signal other than the one being monitored.
Active noise control ( ANC ), also known as noise cancellation ( NC ), or active noise reduction ( ANR ), is a method for reducing unwanted sound by the addition of a second sound specifically designed to cancel the first. The concept was first developed in the late 1930s; later developmental work that began in the 1950s eventually resulted in ...