Abstract: A test system implemented method is for measuring the noise margin of a repeating signal under test (SUT). The method includes determining a digitizer noise of a digitizer channel of the test system, and applying the repeating SUT to the digitizer channel of the test system. An oversampled equivalent-time waveform representation of the repeating SUT is acquired, and then a filtered waveform representation is obtained. A noise margin om of the repeating SUT is determine in accordance with the equation ?m=(?c2+?i2??d2)1/2, where ?c is a standard deviation of a maximum amount of gaussian noise that can added to the filtered waveform representation without its symbol error rate (SER) exceeding a target value, ?i is a standard deviation of the digitizer noise, and ?d is a standard deviation of the noise components removed to obtain the filter waveform representation.

Abstract: A test system implemented method removes intrinsic noise from a waveform representation of a repeating signal under test (SUT). The method includes obtaining an oversampled equivalent-time waveform representation of the repeating SUT. The method further includes obtaining a time-domain representation of a combined noise of the equivalent-time waveform above the deterministic maximum frequency by applying the equivalent-time waveform to a high-pass filter. The method further includes determining a standard deviation of the time-domain representation of the combined noise, and determining a correction factor ? in accordance with the standard deviation of the digitizer noise, and the standard deviation of the time-domain representation of the combined noise.

Abstract: A sampling method that determines the deterministic and random components of a signal when the magnitude of the signal exceeds the range of the sampler.