(19)
(11) EP 1 441 562 A3

(12) EUROPEAN PATENT APPLICATION

(88) Date of publication A3:
21.11.2007 Bulletin 2007/47

(43) Date of publication A2:
28.07.2004 Bulletin 2004/31

(21) Application number: 04005270.6

(22) Date of filing: 05.03.2004
(51) International Patent Classification (IPC): 
H04R 25/00(2006.01)
(84) Designated Contracting States:
AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IT LI LU MC NL PL PT RO SE SI SK TR
Designated Extension States:
AL LT LV MK

(30) Priority: 06.03.2003 EP 03005047

(71) Applicant: PHONAK AG
8712 Stäfa (CH)

(72) Inventors:
  • Allegro, Silvia
    8618 Oetwil am See (CH)
  • Timms, Olegs
    8046 Zürich (CH)
  • Hersbach, Adam
    AU-The Patch VIC, 3792 (AU)
  • McDermott, Hugh
    AU-Mt Macedon VIC,3441 (AU)
  • Dijkstra, Evert
    2046 Fontaines (CH)

(74) Representative: Rigling, Peter Daniel 
Troesch Scheidegger Werner AG Schwäntenmos 14
8126 Zumikon
8126 Zumikon (CH)

   


(54) Method for frequency transposition and use of the method in a hearing device and a communication device


(57) A method for frequency transposition in a communication device or a hearing device, respectively, is disclosed by transforming an acoustical signal into an electrical signal (s) and by transforming the electrical signal from time domain into frequency domain to obtain a spectrum (S). A frequency transposition is being applied to the spectrum (S) in order to obtain a transposed spectrum (S'), whereby the frequency transposition is being defined by a nonlinear frequency transposition function. Thereby, it is possible to transpose lower frequencies almost linearly, while higher frequencies are transposed more strongly. As a result thereof, harmonic relationships are not distorted in the lower frequency range, and at the same time, higher frequencies can be moved to a lower frequency range, namely to an audible frequency range of the hearing impaired person. The transposition scheme can be applied to the complete signal spectrum without the need for switching between non-transposition and transposition processing for different parts of the signal. Therefore, no artifacts due to switching are encountered. A higher transmission quality is obtained because more information is taken into account for the transmission.







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