A Method for Accurate Estimation of Instantaneous Frequency Considering Aliasing of Oscillation Components

Abstract

When the instantaneous frequency is estimated for a single sine wave using a finite-order Hilbert transformer, the estimated value contains an oscillation component that is an even multiple of the input signal frequency. However, the conventional method does not take into account the aliasing that occurs in the oscillation component. In this paper, we show that designing a variable filter that takes into account the aliasing of the oscillation component can achieve higher estimation accuracy.