High quality detection in FM stereo radio signal

摘要

The present document relates to audio signal processing, in particular to an apparatus and a corresponding method for improving an audio signal of an FM stereo radio receiver. In particular, the present document relates to a method and system for reliably detecting the quality of a received FM stereo radio signal and for selecting an appropriate processing based on the detected quality. An apparatus (20) configured to estimate the quality of a received multi-channel FM radio signal is described. The received multi-channel FM radio signal is representable as a mid signal and a side signal, and the side signal is indicative of a difference between a left signal and a right signal. The apparatus (20) comprises a power determination unit configured to determine (101) a power of the mid signal, referred to as mid power, and a power of the side signal, referred to as side power; a ratio determination unit configured to determine (102) a ratio of the mid power and the side power, thereby yielding a mid-to-side ratio; and a quality determination unit configured to determine (105) a quality indicator of the received FM radio signal based at least on the mid-to-side ratio.

主权项

1. A system configured to generate an improved stereo signal of a received FM radio signal; wherein the received FM radio signal is representable as a mid signal and a side signal; wherein the side signal is indicative of a difference between a left signal and a right signal; the system comprising:
a power determination unit configured to determine a plurality of powers for a plurality of subbands of the mid signal, referred to as subband mid powers, and a plurality of powers for a plurality of corresponding subbands of the side signal, referred to as subband side powers; a ratio determination unit configured to determine a plurality of subband mid-to-side ratios as the ratios of the plurality of subband mid powers and the plurality of subband side powers; a quality determination unit configured to determine a quality indicator of the received FM radio signal from the minimum of the plurality of subband mid-to-side ratios across the plurality of subbands; wherein the system is configured to generate the improved stereo signal in dependence of the determined quality indicator.