Circuit arrangement for deriving signals for masking audio signals

摘要

PCT No. PCT/DE94/00321 Sec. 371 Date Aug. 25, 1995 Sec. 102(e) Date Aug. 25, 1995 PCT Filed Mar. 22, 1994 PCT Pub. No. WO94/22229 PCT Pub. Date Sep. 29, 1995The circuit arrangement includes a first low-pass filter (2) for filtering an input signal (H3) proportional to the strength of a received radio signal; a second low-pass filter (3) for filtering the input signal (H3); a first weighting circuit (7) for weighting the first low-pass filter output signal with first coefficients to form a first weighted output signal; a circuit device for forming a masking signal for reducing stereo channel isolation from the first weighted output signal; a second weighting circuit (5) for forming a second weighted output signal weighted with second coefficients from the first low-pass filter output signal or the second low-pass filter output signal according to a switching signal (DD2) indicative of interference in the audio signals; a switch device (4) for selecting the first low-pass filter output signal for weighting in the second weighting circuit means (5) when no interference is indicated by the switching signal (DD2) and the second low-pass filter output signal for weighting in the second weighting circuit means (5) when interference is indicated by the switching signal (DD2); and a circuit device for forming a masking signal for damping the audio signal from the second weighted output signal.