Method and circuit arrangement for acoustically compensating for the environmental noise in headphone reception

摘要

In a very noisy environment, considerable losses of intelligibility can occur even in headphone reception. To compensate for the acoustic feedback in a hands-free talking station, an additional signal is fed into the listening path. The component of the additional signal acoustically fed back to the microphone from the loudspeaker is compared with the additional signal fed in, the magnitude of the feedback factor is determined and the volume of the loudspeaker is set as a function of this. To be able to carry out a simple adaptation to the respective interfering noise in a very noisy environment, the environmental noise picked up by a reference microphone is used as the additional signal according to the invention. The environmental noise picked up by the reference microphone is supplied to a compensation filter and the filter output signal is superimposed in negated form on the useful signal in a loudspeaker located at the end of the listening path.