Modified CCPLL for demodulation of two FM signals with overlapping spectra

Abstract

A demodulator of two FM signals with overlapping spectra, which is based on a cross coupled phase locked loop (CCPLL), system, is investigated. It is shown that the application of an additional PLL as an FM demodulator of an input mixture (two FM signals) is advantageous. The new configuration of CCPLL demodulator overcomes the main disadvantage of the known CCPLL based demodulator, i.e. existence of nonstable regions within which a demodulator's output converges to a false state.