RECEIVER ANGLE REMODULATION

摘要

A receiver for angle-modulated signals of the type a sin(( omega )t+ phi (t)), comprising a frequency transposition stage (3) incorporating a local oscillator (3-1). A frequency shift DELTA omega of the local oscillator relative to the carrier frequency omega may cause the angle modulation signal phi (t) to become faded. An argument detector (4) produces the signal [ phi (t)+( DELTA omega )t] which is differentiated by a differentiator (6) to provide the signal [d phi (t)/dt+ DELTA omega ]. A DC-shift detector (7) determines the DC-component DELTA omega of this signal. This component is integrated by an integrator (8) to provide the signal ( DELTA omega )t, which is thereafter subtracted by difference producer (5) from the output signal of the argument detector (4) to provide a clear angle modulation signal.