Ciomparison of frequency measurement between time-domain and frequency-domain in DSO

In this paper, a frequency measurement method between time-domain and frequency-domain in a digital storage oscilloscope (DSO) is considered. The conclusion is obtained: when the signal is periodic, the routine time-domain method may be adopted; under lower signal-to-noise condition, the autocorrelation method overmatches the routine time-domain method. But when the signal is non-periodic, the frequency-domain method is preferred.