A radio noise source is a device that emits
radio wave
Radio waves are a type of electromagnetic radiation with the longest wavelengths in the electromagnetic spectrum, typically with frequencies of 300 gigahertz ( GHz) and below. At 300 GHz, the corresponding wavelength is 1 mm (sho ...
s at a certain
frequency
Frequency is the number of occurrences of a repeating event per unit of time. It is also occasionally referred to as ''temporal frequency'' for clarity, and is distinct from ''angular frequency''. Frequency is measured in hertz (Hz) which is eq ...
, used to
calibrate
In measurement technology and metrology, calibration is the comparison of measurement values delivered by a device under test with those of a calibration standard of known accuracy. Such a standard could be another measurement device of known ...
radio telescope
A radio telescope is a specialized antenna and radio receiver used to detect radio waves from astronomical radio sources in the sky. Radio telescopes are the main observing instrument used in radio astronomy, which studies the radio frequency ...
s such that received data may be compared to a known value, as well as to find the
focal point
Focal point may refer to:
* Focus (optics)
* Focus (geometry)
* Conjugate points, also called focal points
* Focal point (game theory)
* Unicom Focal Point
UNICOM Focal Point is a portfolio management and decision analysis tool used by the p ...
of a telescope soon after construction, so that the
wave guide
A waveguide is a structure that guides waves, such as electromagnetic waves or sound, with minimal loss of energy by restricting the transmission of energy to one direction. Without the physical constraint of a waveguide, wave intensities ...
and
front end may be properly located.
Noise
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