A computer-based method for measuring a ringup, a ringdown and a ringback of an electronic signal is provided. The method includes fitting a ringdown fitting curve to approximate a first ringdown data, and fitting a ringup fitting curve to approximate a first ringup data. The method further includes calculating an approximate ringdown value according to the ringdown fitting curve, and calculating an approximate ringup value according to the ringup fitting curve. The approximate ringup and ringdown values are then used to obtain an accurate ringup value and an accurate ringup value respectively. An accurate ringback value is calculated by subtracting the accurate ringup value from the accurate ringdown value.