关键词: 超声波, 手势识别, 多普勒效应

Abstract: With the rapid development of smart phones, people’s life has been improved. User experience of mobile device can be improved in many scenarios with the assist of in-air gesture recognition. In this paper, AGRS, an in-air gesture recognition system that can be applied to off-the-shelf smart devices is proposed. In AGRS, the loudspeaker is used to emit a continuous 20 kHz tone and the microphone is used to receive the gesture-reflecting ultrasonic wave. AGRS can recognize the position of mobile device by the gyroscope. After the gesture has been separated from noise, AGRS adapts CFAR algorithm. The characteristic of ultrasonic can be extracted by using the Doppler shift and be handled by FFT conversion. Finally, suitable classifier has been chosen to recognize gestures of AGRS. The experimental results demonstrate that AGRS is able to achieve gesture recognition accuracy of above 95%.

Key words: ultrasonic, gesture recognition, Doppler