Patent ID: 8520779

Claim:
A method for audio noise reduction of frequency modulation (FM) receiver, wherein after receiving a FM signal having a pilot tone, a pilot carrier sync detector performs a pilot carrier synchronization detection of the FM signal, a FM demodulator demodulates the synchronized FM signal, a multiplex decoder decodes an audio signal of the demodulated FM signal for outputting the decoded audio signal, and a noise reduction controls the multiplex decoder for controlling noise attenuation associated with the decoded audio signal according to RSSI, the method comprising the steps of: (a) performing a phase error detection for detecting the phase error of phase-locked loop (PLL) of the pilot carrier sync detector; (b) determining whether noise exists by comparing the phase error with a threshold value to determine whether the noise exists in the phase error; and (c) performing a noise reduction step by outputting a noise reduction control signal to the noise reduction based on the determination in step (b) for reducing the noise in the noise existence interval.