Difference Between Noise Figure And Noise Floor

The terms noise factor and noise figure are interchangeably used in rf and microwave field.

Difference between noise figure and noise floor.

So this may well be where these two become even more of an issue. Noise floor can be derived from the gain g input noise ni and the internally generated noise na as shown below. Noise figure is just log scaled value of noise factor as shown below. This is all about the noise figure but if you want to play more with math.

This page on noise factor versus noise figure describes difference between noise factor and noise figure. Then there is weighted noise figure measured when a frequency is applied to the noise floor. By the way don t spend any time thinking about gain and noise figure beyond one or two decimal digits in practice you ll never be able to measure the difference between 3 812 and 3 8 db. Noise level is expressed by the amplifier noise figure.

Mds 92 5 10 82 5. The noise figure is the difference in decibels db between the noise output of the actual receiver to the noise output of an ideal receiver with the same overall gain and bandwidth when the receivers are connected to matched sources at the standard noise temperature t 0 usually 290 k. The noise power from a simple load is equal to ktb where k is boltzmann s constant t is. Noise factor versus noise figure.

To calculate the actual minimum detectable signal is simply a case of adding the required snr in db to the noise floor. Thus noise figure is independent of the input signal level. Noise is always present and received on a radio even when no wanted signals are present. If we need the signal to be 10 times more powerful than the noise floor the required snr would be 10 db.

So for the example above this would mean that the minimum detectable signal is. The noise figure for a circuit is the. The level of the noise floor determines the lowest strength signals that can be received and therefore the noise floor level is an important characteristic of any radio.