This paper aims to propose a simple way to detect the frequency of electrical signals based on zero-crossing point algorithms. First, by using Fourier algorithm as a digital filter to fetch the baseband Sine and Cosine portions of signals, and then a zero crossing algorithm technology is applied to sine or cosine signal to calculate the frequency of the sine wave signal. It is intended to apply this theoretical development in personal computers to analyze the operation of the extracted signal. However, this computer must be equipped with DAQ (Data Acquisition Card) device and supervisory control and data acquisition (SCADA)-based software LabVIEW to filter the acquired signals stored in memory and then determines the signal frequency by the zero-crossing algorithms. This developed system can be simulated with a high-order harmonic generation and noise signal source, and the program can be used to estimate the frequency of baseband sinusoidal signals. Experiments show that the zero-crossing algorithm is an effective method of measuring the frequency.
