Abstract: A method for measuring frequency includes the steps of obtaining the cycle number of the clock rate of a signal under test based on a reference signal and a clock mask synchronous with the signal under test; obtaining a frequency of the signal under test based on the cycle number; correcting the frequency of the signal under test based on a plurality of phase shift signals generated based on the reference signal; and minimizing an error of the frequency of the signal under test by increasing the quantity of the phase shift signals. The method enhances the accuracy of the obtained frequency of the signal under test, speeds up frequency measurement, and reduces the required circuit areas. A system for measuring frequency is further introduced for use with the method.

Abstract: A frequency counter obtains a cycle number of a clock of a target signal by a reference signal and a clock mask synchronous with the target signal, calculates a frequency of the target signal based on the cycle number, corrects the frequency according to a plurality of phase shift signals generated based on the reference signal, and minimizes an error of the calculated frequency by increasing the quantity of the phase shift signals, so as to enhance the accuracy of the calculated frequency of the target signal, speed up measurement, and reduce required circuit areas.