Noise

 

Noise is the background signal detected that is as a result of typically the following:

 

  • Statistical Noise on Signal (Shot Noise)

Causes and symptom's include:

- s = ÖN

- Appears only as fluctuations in signal

- Relative magnitude decreases as signal increases

- s/signal = 1/ÖN = RSD

 

  • Field Emission (Cold Noise)

Causes and Symptoms include:

- Poorly finished parts or dust, hair or other foreign objects

- There is a threshold voltage where it onsets

- Typified by random spaced pulses with no apparent trend

 

  • Outgassing

Symptoms include:

- Occurs in bursts of many phases

- Trend may increase with temperature rise

- Will eventually show a decreasing trend unless it is a 'virtual' peak