Radio interference reduction system - uses secondary phase demodulated and quadrature filtered path to cancel main path interference

摘要

The circuit is designed to achieve a reduction of noise in a radio channel. The equipment si designed for simplicity and especially to reduce doppler interference. The equipment can be used for AM or FM signals, and also for phase modulated channels. The signal is divided between an equalising network (G) which is connected to the multiplier (M) and a phase demodulator (PDM) and Quadrature filter (QF) which are also connected to the multiplier.