(19) |
 |
|
(11) |
EP 0 482 699 A3 |
(12) |
EUROPEAN PATENT APPLICATION |
(88) |
Date of publication A3: |
|
19.08.1992 Bulletin 1992/34 |
(43) |
Date of publication A2: |
|
29.04.1992 Bulletin 1992/18 |
(22) |
Date of filing: 16.10.1991 |
|
(51) |
International Patent Classification (IPC)5: G10L 9/14 |
|
(84) |
Designated Contracting States: |
|
AT BE CH DE DK ES FR GB GR IT LI LU NL SE |
(30) |
Priority: |
23.10.1990 NL 9002308
|
(71) |
Applicant: Koninklijke PTT Nederland N.V. |
|
NL-2509 CH The Hague (NL) |
|
(72) |
Inventors: |
|
- Beerends, John Gerard
NL-2515 NB The Hague (NL)
- Muller, Frank
NL-2623 NJ Delft (NL)
- van Ravesteijn, Robertus Lambertus Adrianus
NL-2275 TB Voorburg (NL)
|
|
|
|
(54) |
Method for coding and decoding a sampled analog signal having a repetitive nature
and a device for coding and decoding by said method |
(57) Frequency components are calculated from the STP-filtered speech signal. The amplitudes
of these are combined in a manner such that the resultant values are associated with
frequencies which are situated equidistantly on a linear Bark scale. Said components
are quantised, possibly after scaling. In the decoder, the components are again distributed
over the frequency spectrum.
In the coder, the fundamental regularity D is determined with an LTP technique, after
which it is transmitted. In the decoder the phases of the reconstructed signal at
the spacing D in the past are determined. These phases are combined with the amplitudes
already present in the frequency spectrum, after which transformation back to the
time domain takes place. Inverse STP filtering is then carried out.