Effects of Impulsive Noise on Phase-Locked Loop FM Demodulator

The effects of impulsive noise on phase-locked loop (PLL) FM demodulators is investigated. The PLL FM demodulator used for the experiments is basically a second order loop employing an active filter. The impulsive noise used for this work is ignition noise. Impulse response of the receiver is investigated and the PLL FM demodulator is digitally simulated. The response of the receiver employing the PLL FM demodulator used in the ground terminal to an input signal consisting of unmodulated carrier and impulses is investigated experimentally. The system margin is fouind to be degraded by about 10 dB.