Signal-to-Noise Ratios in Band-Pass Limiters

A general analysis is made of the relations between output signal and noise powers and input signal and noise powers for band-pass limiters having odd symmetry in their limiting characteristics. Specific results are given for the case where the limiter has an nth root characteristic, and they include the ideal symmetrical limiter (or clipper) as a limiting case. This analysis shows that, for the band-pass limiter, the output signal-to-noise power ratio is essentially directly proportional to the input signal-to-noise power ratio for all values of the latter. This result is due to the band-pass characteristics rather than to the symmetrical limiting action.