Abstract

A super-directive microphone system using digital signal processing has been developed for in-vehicle speech recognition systems for the North American market, in order to increase the recognition accuracy of these systems in high noise environments.The developed microphone system uses a new super-directive algorithm with a high directional noise reduction rate that functions to reduce noise, such as passenger utterances. To enable adaptation of the algorithm to different in-vehicle noise environments, such as while operating the air conditioner and opening/closing the windows, the system also incorporates an omni-directional microphone and an analog high pass filter. The use of the new system increases recognition accuracy in a variety of noise environments.

References

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Author (organization or company)

• Toshiya SHIKANO（Automobile R&D Center）
• Junichi WATANABE（FUJITSU LIMITED）
• Naoshi MATSUO（FUJITSU LABORATORIES LTD）

Publication Information

Article of Honda R&D Technical Review Vol.20 No.2 (26 - 31)

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