The tool calculates the thermal noise floor of a radio receiver.
- Temperature in either Kelvin or Celsius
- Noise Figure in dB
Noise Floor of a Radio Receiver
In a radio receiver, the noise floor is the level below which a signal will not be detected. In practice, a signal has to be at least a few dB higher before it can be detected.
Spectrum analyzers have a specification called the Displayed Average Noise Level (DANL) which is the same as the Noise Floor. It depends on frequency and is normalized to 1 Hz bandwidth (dBm/Hz).
Example Noise Floor Calculation
For a temperature of 27oC, 100 MHz Bandwidth and a noise figure of 3 dB, the noise floor is -90.83 dBm.