Speech bandwidth extension
AssigneeTelefonaktiebolaget L M Ericsson (publ)
InventorHarald Gustafsson
Life of this patent
Estimating the term…
Abstract
A common narrow-band speech signal is expanded into a wide-band speech signal. The expanded speech signal gives the impression of a wide-band speech signal regardless of what type of vocoder is used. Extending the narrow-band speech signal into a lower range involves analyzing the narrow-band speech signal to generate one or more parameters, and synthesizing a lower frequency-band signal based on at least one of the one or more parameters. The synthesized lower frequency-band signal is then combined with a signal that is derived from (e.g., via up-sampling) the narrow-band speech signal. In preferred embodiments, a pitch frequency parameter is generated, and generation of the lower frequency-band signal includes generating continuous sine tones that are frequency shifted with the pitch frequency parameter.
Claims20
A method of generating a wide-band speech signal from a first narrow-band speech signal, the method comprising:
- analyzing the first narrow-band speech signal to generate one or more parameters;
- synthesizing a lower frequency-band signal based on at least one of the one or more parameters;
- and
- combining the synthesized lower frequency-band signal with a second narrow-band speech signal that is derived from the first narrow-band speech signal,
- wherein:
- the one or more parameters include a pitch frequency parameter;
- and
- synthesizing the lower frequency-band signal based on at least one of the one or more parameters comprises generating continuous sine tones that are based on the pitch frequency parameter.
An apparatus for generating a wide-band speech signal from a first narrow-band speech signal, the apparatus comprising:
- logic that analyzes the first narrow-band speech signal to generate one or more parameters;
- logic that synthesizes a lower frequency-band signal based on at least one of the one or more parameters;
- and
- logic that combines the synthesized lower frequency-band signal with a second narrow-band speech signal that is derived from the first narrow-band speech signal,
- wherein:
- the one or more parameters include a pitch frequency parameter;
- and
- the logic that synthesizes the lower frequency-band signal based on at least one of the one or more parameters comprises logic that generates continuous sine tones that are based on the pitch frequency parameter.
Dependencies are inferred from the claim text.