Instantaneous Extraction of Frequency Components of the FM Signals by Time Domain Processing and Its Applications

Abstract

This paper investigates the momentary extraction of a part of the frequency components of the signal resulting from the frequency modulation process. Based on this analysis, a new method for extracting frequency information is proposed. The changes of the instantaneous periods of the FM signal are investigated, and a simple method to determine the instantaneous frequency of the signal in the time domain is proposed. The proposed method was evaluated through simulations and compared against conventional FM demodulation techniques. In similar SNR, the relative error power of the proposed method is approximately 2 dB less than other conventional types of FM demodulators. © 2025 The Author(s). IET Communications published by John Wiley & Sons Ltd on behalf of The Institution of Engineering and Technology.