| 摘要 |
The noise in a frequency demodulated audio signal is detected on basis of the characteristics of the stereo-multiplex signal to obtain a very reliable information that can be used for the sliding stereo-mono transition, noise blanking and a de-noising of the stereo-difference signal. A noise signal (vd,l(t)-vd,u(t) or vd,u(t)-vd,l(t)) is calculated by subtracting one sideband of the stereo-difference signal from the other sideband of the stereo-difference signal and as a direct measure for the quality of the signal generating the variance (sigma<2>vd) of the noise signal by squaring and thereafter averaging the noise signal.
|
