Patent ID: 8837757
Filing Date: 2014-09-16
Classification: H04R

Abstract:
1. A system for measuring the occlusion effect comprising a hearing aid adapted for operation in a sound amplification mode and for operation in an occlusion measurement mode, said hearing aid comprising a microphone adapted for transforming an acoustic sound level external to a hearing aid user's ear canal into a first electrical signal, said first electrical signal being guided to an A/D converter forming a first digitized electrical signal, a receiver adapted for generating acoustic sounds in the ear canal of a user when in said amplification mode, and adapted for, when in said occlusion measurement mode, transforming the acoustic sound level in the ear canal into a second electrical signal, and means for directing the second electrical signal obtained by the receiver in occlusion measurement mode to an A/D converter forming a second digitized electrical signal, said system comprising a signal processing means comprising a filter bank for splitting an electrical signal into different frequency bands, wherein said system is adapted for, when measuring the occlusion effect with said hearing aid in occlusion measurement mode, having said signal processing means apply said filter bank for splitting the first and the second digitized electrical signals into respective first and second band split digitized electrical signals, respectively, said first and second band split digital electric signals each representing the signal in a number of separate frequency bands, and wherein said hearing aid comprises means for transmitting simultaneous samples of the first and the second band split digitized electrical signals to calculating means for calculating the occlusion effect, said calculating means comprising a detector bank for measuring the level of the signal in each frequency band, and said calculation being based on a ratio between simultaneous samples of the first and the second band split digital electric signals, wherein said second electrical signal is equalized before said filter bank in order to compensate the frequency dependent transfer functions of the hearing aid receiver when used as a microphone.