Hard Limiting of a Signal Plus Noise
Daniel B. Talbot · 2012
A hard limiter is defined as a circuit block that outputs only two levels: +1 and -1 or a scaled version of the same. An example is a comparator having one input at ground and the other input connected to the composite signal plus noise. The noise may be incoming from outside the comparator or it may be within the comparator input node(s). The signal-to-noise ratio is somewhat preserved at the limiter output. Phase noise is multiplicative, that is, one cannot have phase noise in the absence of a signal, since a signal must be present to be modulated by the phase noise. Controlled Vocabulary Terms phase noise; Signal to noise ratio