Audio signal of an FM stereo radio receiver by using parametric stereo

A method for improving a left/right or mid/side audio signal output by a frequency modulation (FM) stereo radio receiver, the method comprising:

• receiving the left/right or mid/side audio signal from the FM stereo radio receiver;
• generating a first audio signal based on the left/right or mid/side audio signal by a downmix operation;
• determining one or more parametric stereo parameters based on the left/right or mid/side audio signal in a frequency-variant;
• receiving the first audio signal and outputting a decorrelated signal;
• and
• generating a stereo signal based on the first audio signal, the one or more parametric stereo parameters, and selectively on:
• a second audio signal or at least a frequency band thereof, the second audio signal being a received side signal or a residual signal, the residual signal indicating an error associated with representing the left/right or mid/side audio signal by the first audio signal and the one or more parametric stereo parameters, or
• the decorrelated signal,
• wherein:
• the generating the stereo signal selectively based on the second audio signal or the decorrelated signal is frequency-variant and uses:
• the second audio signal for a first frequency range and
• the decorrelated signal for a second frequency range,
• the frequencies of the first frequency range being lower than the frequencies of the second frequency range.