Beat Noise Suppression Using Adaptive Line Enhancers for FM Radio in Motor Vehicles

Abstract

There exists interference in a frequency modulation (FM) radio wave in a motor vehicle. The interference is called as a beat noise which is an electromagnetic radiation caused from electronic devices equipped on the motor vehicle. The beat noise becomes a perceptual sinusoidal noise and/or breaks a spectral structure of a broadcasting sound. It is required to suppress the beat noise by using a low cost device such as a DSP with a low-clock frequency. This paper proposes a noise suppressor employing two adaptive line enhancers as a promising method to be implementable on a DSP with low-clock frequency. We apply the proposed noise suppressor to signals obtained in the middle of the demodulation process. Simulation results show that the proposed method effectively suppresses the beat noise and extracts the broadcasting sound with high accuracy.