Algorithmic Measurement of Digital Instantaneous Frequency

This paper presents an algorithmic method for measuring the instantaneous frequency of a uniformly sampled FM signal. The measured parameter, termed digital instantaneous frequency, is defined in a manner similar to that used to describe frequency-modulated, continuous-time signals. The measurements are derived from an adaptive linear prediction spectral estimates. The proposed algorithm is utilized in the development of a digital processor for FM demodulation which operates on a uniformly sampled FM signal, and its output is a sampled sequence of the estimated demodulated message. The performance of the digital processor is demonstrated and compared with that of a conventional FM discriminator.