Method and Arrangements for Audio Signal Encoding

A method for forming an audio signal, comprising:

• forming a frequency component of the audio signal allotted to a first subband of the audio signal by a subband decoder based on fundamental period values each specifying a fundamental period of the audio signal;
• deriving a fundamental period parameter from the fundamental period values;
• forming a pulse with a pulse shape depending on the fundamental period parameter at an interval determined by the fundamental period parameter;
• mixing the pulse with a noise signal for creating an excitation signal specified for a second subband of the audio signal;
• and
• forming a frequency component of the audio signal allotted to the second subband by exciting an audio synthesis filter with the excitation signal.

An audio signal decoder for forming an audio signal, comprising:

• a subband decoder that forms a frequency component of the audio signal allotted to a first subband based on fundamental period values each specifying a fundamental period of the audio signal;
• an audio synthesis filter;
• and
• an excitation signal generator that generates an excitation signal for forming a frequency component of the audio signal allotted to a second subband by exciting the audio synthesis filter with the excitation signal, the excitation signal generator comprising:
• a derivation device that derives a fundamental period parameter from the fundamental period values,
• a noise generator that forms a noise signal,
• a pulse generator that forms a pulse with a pulse shape depending on the fundamental period parameter at an interval determined by the fundamental period parameter, and
• a mixing device that mixes the pulse with the noise signal.

An audio signal encoder, comprising:

• an audio signal decoder that forms an audio signal, the audio signal decoder comprising:
• a subband decoder that forms a frequency component of the audio signal allotted to a first subband based on fundamental period values each specifying a fundamental period of the audio signal,
• an audio synthesis filter, and
• an excitation signal generator that generates an excitation signal for forming a frequency component of the audio signal allotted to a second subband by exciting the audio synthesis filter with the excitation signal, the excitation signal generator comprising:
• a derivation device that derives a fundamental period parameter from the fundamental period values,
• a noise generator that forms a noise signal,
• a pulse generator that forms a pulse with a pulse shape depending on the fundamental period parameter at an interval determined by the fundamental period parameter, and
• a mixing device that mixes the pulse with the noise signal;
• and
• a comparison device that matches the audio signal formed by the audio signal decoder to an audio signal to be transmitted.