Design of Discrete Time Demodulators of AM- and FM-Harmonic Signals Using Energy Operators

The mathematical models and structure-functional diagrams of new discrete time demodulators of amplitude modulated (AM-) and frequency modulated (FM-) signals are proposed. The models are determined in a form of difference equations with given initial conditions. Appropriate functional block-diagrams of the demodulators consist discrete time differentiators, integrators, summers, multipliers, dividers and functional transformers. The structure and parameters of demodulators are independent of a carrier frequency. The proposed demodulators do not need a filtering of output signals. In the conditions of small level noises in input signals the demodulators can be used without any additional tools. An affect of high level noises can be minimized to an acceptable magnitude if input signals before demodulator are passed through a set of narrow band filters with an obtaining on its output almost monochromatic signals.