Distributed speech recognition

• US 20020152065A1
• Filed: 02/27/2002
• Published: 10/17/2002
• Est. Priority Date: 07/05/2000
• Status: Abandoned Application

• Current Assignee: Alcatel SA (Nokia Corporation)
• Original Assignee: Alcatel SA (Nokia Corporation)
• Inventors: Sienel, Jurgen, Kopp, Dieter, Knoblich, Ulf
• Application Number:
  US10/069,577
• Publication Number:
  US 20020152065A1
• Time in Patent Office: Days
• US Class Current: 704/203
• CPC Class Codes: G10L 15/30 Distributed recognition, e.g. in client-server systems, for mobile phones or network applications
• CPC Class Codes: G10L 19/0204 using subband decomposition
• CPC Class Codes: H04M 1/271 controlled by voice recognition
• CPC Class Codes: H04M 2201/40 using speech recognition

Abstract

Distributed Speech Recognition (DSR) systems comprise terminals having a complex preprocessing unit and a network having a final processing unit. By leaving a Fast Fourier Transformation (FFT) together with a filtering function and a compression in said preprocessing unit by shifting both nonlinear transformation as well as a Discrete Cosine transformation (DCT) from said preprocessing unit into said final processing unit, where both follow decompression, said terminals are of a lower complexity. By using a MEL-filter (melody-filter) which preferably is adaptable, said low complex terminals are made more flexible.

Claims

1. Terminal comprising a preprocessing unit for distributed speech recognition, with a network comprising a final processing unit, with said preprocessing unit comprising a transformator for transformating audio signals and comprising a filter for filtering transformated audio signals and comprising a compressor coupled to said filter and with said final processing unit comprising a decompressor, characterised in that said compressor is coupled to said filter via a transformationless coupling.

2. Terminal according to claim 1, characterised in that said filter comprises a combiner for at least combining a first number of frequency-components situated at first frequencies and combining a second number of frequency-components situated at second frequencies, with said first number being smaller than said second number and with said first frequencies being lower than said second frequencies.

3. Terminal according to claim 2, characterised in that said filter comprises a control input—

for receiving a control signal for adapting said combining.

4. Preprocessing unit for use in a terminal comprising said preprocessing unit for distributed speech recognition, with said preprocessing unit comprising a transformator for transformating audio signals and comprising a filter for filtering transformated audio signals and comprising a compressor coupled to said filter, characterised in that said compressor is coupled to said filter via a transformationless coupling.

5. Preprocessing unit according to claim 4, characterised in that said filter comprises a combiner for at least combining a first number of frequency-components situated at first frequencies and combining a second number of frequency-components situated at second frequencies, with said first number being smaller than said second number and with said first frequencies being lower than said second frequencies.

6. Preprocessing unit according to claim 5, characterised in that said filter comprises a control input for receiving a control signal for adapting said combining.

7. Network comprising a final processing unit for distributed speech recognition, with a terminal comprising a preprocessing unit, with said preprocessing unit comprising a transformator for transformating audio signals and comprising a filter for filtering transformated audio signals and comprising a compressor coupled to said filter and with said final processing unit comprising a decompressor, characterised in that said final processing unit comprises a transformator for performing a nonlinear transformation and/or a discrete cosine transformation, with said compressor being coupled to said filter via a transformationless coupling.

8. Final processing unit for distributed speech recognition, with said final processing unit comprising a decompressor, characterised in that said final processing unit comprises a transformator for performing a discrete cosine transformation and/or a nonlinear transformation.

9. Method for use in a telecommunication comprising a terminal and a network, with said terminal comprising a preprocessing unit and with said network comprising a final processing unit for distributed speech recognition, with said method comprising a first step of transformating audio signals in said terminal and a second step of filtering transformated audio signals in said terminal and a third step of performing a compression in said terminal and a fourth step of performing a decompression in said network, characterised in that said third step follows said second step transformationlessly.

10. Method according to claim 9, characterised in that said second step comprises a first substep of combining a first number of frequency-components situated at first frequencies and a second substep of combining a second number of frequency-components situated at second frequencies, with said first number being smaller than said second number and with said first frequencies being lower than said second frequencies.