A Method to Reduce the Spectrum Leakage Effect

The signal spectrum is one of its main parameters, since it allows indirect calculation of most of its other parameters. It is known that the main reason for the occurrence of methodical error in spectrum measurement is the “spectral leakage” effect. To eliminate the “spectral leakage”, the simplest way is to adjust the number of samples to the current frequency value. The dependences of the amplitude spectrum error on the frequency deviation, initial phase, amplitude, and the sampling frequency are obtained. An analytical expression is obtained that allows estimating the measurement error of the amplitude spectrum for the case of sinusoidal signal. A compensation method is proposed that allows significantly reducing the resulting measurement error of the amplitude spectrum. A modified vernier approach is proposed, which allows reducing the resulting measurement error with minor additional computational costs. The modification consists in compensating for the measurement error by using analytical relations.