Digital frequency modulation system and method

Digital frequency modulator

Digital frequency shift key modulator

Digital FSK time rate of change modulator

Digital method of pulse width modulation

Digital modulation apparatus

Digital modulator with variations of phase and amplitude modulat

Digital MSK modulator

Digital phase and amplitude modulator

Digital phase domain amplitude modulation method and apparatus

Digital phase-locked loop frequency modulator

Digital PSK modulator for modem

Digital voice and data frequency modulation circuit

Digitized frequency synthesizer

Digitized phase modulating means

Digitized phase modulating means

Diode ring mixer

Direct modulation 4 phase PSK modulator

Directional PSK modulation and demodulation system

Double balanced modulator-demodulator