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Expressing Noise Levels
The noise quality of a receiver can be expressed in the following terms:
The noise factor is the ratio of the S/N power at the input to the S/N power at the output.
When the noise factor is expressed in decibels, it is called the noise figure.
Most of the noise produced in a device is thermal, which is directly proportional to temperature. Therefore, the term noise temperature (TN) is used.
SINAD is the composite gnal plus oise nd istortion divided by noise and distortion contributed by the receiver.