Identification of Secondary Path Irregularities for Active Noise Control Headphones
نویسنده
چکیده
Headphones with feedback Active Noise Control (ANC) have some advantages over feedforward applications [1], but suffer from the risk of instabilities. A block diagram of a typical digital feedback ANC headphone (compare [1], [2]) is shown in Fig. 1. The performance and stability of this system depends on the modelling accuracy of the secondary path (i.e. the transfer function from the loudspeaker to the error-microphone inside the ear cup). The model Ŝ can easily be determined off-line [2], but the actual secondary path S will change considerably once the headphone is lifted or pulled away.
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