Speech Recognisation

Speech Recognition Using FPGA Technology

Authors: Carlos Asmat 260148251 David López Sanzo 260146414 Kanwen Wu 260045745

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Design Project Laboratory ECSE 494

Submitted on June 18, 2007

Department of Electrical Computer and Software Engineering

Speech Recognition Using FPGA Technology

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Abstract

An increasingly popular way to interact with machines is to simply talk to them. However, there is often a trade-off between ease of use and system complexity. Thus, the main objective of this project is to design and implement a speech recognition system using a Field Programmable Gate Array (FPGA). It must be capable of accurately identifying a single sound while remaining simple and fast. For this purpose, an algorithm is prototyped and tested using MATLAB™, before being implemented on an Altera DE2 board. Complications in acquiring a Fast Fourier Transform (FFT) module lead to a partial, yet functional hardware implementation.

Carlos Asmat

David López Sansò

Kanwen Wu

Speech Recognition Using FPGA Technology

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Acknowledgments

The authors would like to express their gratitude towards Professor Miguel Marin, who provided guidance throughout the realization of this project. They would also like to acknowledge the great interest Professor Richard Rose showed by answering questions, especially regarding the FFT. Finally, they thank Professor James J. Clark for his guidance in the choice of a development board.

Carlos Asmat

David López Sansò

Kanwen Wu

Speech Recognition Using FPGA Technology

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Table of Contents

Introduction................................................................................................................................................1 Chapter 1:Background Theory...................................................................................................................2 1.1 Speech Recognition Principle........................................................................................................ 2 1.2 Data Acquisition.............................................................................................................................2 1.3 Detection........................................................................................................................................ 2 1.4 Frequency Content......................................................................................................................... 3 1.5 Distance.......................................................................................................................................... 4 Chapter 2:Hardware Implementation.........................................................................................................5 2.1 Wolfson Interface........................................................................................................................... 5 2.1.1 I2C Bus Controller..................................................................................................................5 2.1.2 Sound fetcher.......................................................................................................................... 6 2.1.3 Clock Module......................................................................................................................... 8 2.2 Detector.......................................................................................................................................... 9 2.3 FFT............................................................................................................................................... 10 2.4 Memory Management.................................................................................................................. 10 2.4.1 Memory Controller............................................................................................................... 11 2.4.2 Memory Batch Operator....................................................................................................... 12 2.5 Distance........................................................................................................................................ 13 2.6 System Controller.........................................................................................................................14 Chapter 3:Results..................................................................................................................................... 15 3.1 FFT Issues.................................................................................................................................... 15 3.2 MATLAB Results........................................................................................................................ 15 3.3 Experimental results..................................................................................................................... 17 Conclusion............................................................................................................................................... 19 Bibliography.............................................................................................................................................20 References................................................................................................................................................ 20 Appendix.................................................................................................................................................. 21 Appendix B.............................................................................................................................................. 24 Appendix C.............................................................................................................................................. 27 Appendix D..............................................................................................................................................