Broadband quadrature phase modulator for control loop error generation in an IF combiner

摘要

Circuitry for use in an IF combiner, where main and diversity receiver path signals are combined. The circuitry generates an error signal for the purpose of controlling the phase of one of these signals by deriving a broad-band phase-modulated feedback path version of the signal. No modulation is introduced into the message channel. The feedback path version of the signal is quadrature modulated and combined with signals from the main and diversity receiver paths to generate an error signal providing maximum control loop sensitivity.