 |
International Workshop on Hands-Free Speech Communication (HSC2001)April 9-11, 2001 |
 |
|
International Workshop on Hands-Free Speech Communication (HSC2001)April 9-11, 2001 |
|
This paper describes a new method for estimating the direction of arrival (DOA) using a nonlinear microphone array based on complementary beamforming. Complementary beamforming is based on two types of beamformers designed to obtain complementary directivity patterns each other. In this system, since the resultant directivity pattern is proportional to the product of these directivity patterns, the proposed method can be used to estimate DOAs even when the number of sound sources is equal to or exceeds that of microphones. First, DOA-estimation experiments are performed using a computer simulation. Results of the experiments show that the proposed method can be used to estimate DOAs with fewer microphones than in the conventional method, especially when the signals are nonstationary, such as speech, and independent of each other. Next, DOA-estimation experiments are performed using actual devices in real acoustic environments. The results clarify that DOA estimation for two speach signals can be accomplished by the proposed method with only two microphones. Also, by comparing the resolutions of DOA estimation by the proposed method and by the conventional minimum variance method, we can show that the performance of the proposed method is superior to that of the conventional method.
Bibliographic reference. Kamiyanagida, Hidekazu / Saruwatari, Hiroshi / Takeda, Kazuya / Itakura, Fumitada / Shikano, Kiyohiro (2001): "Direction of arrival estimation using nonlinear microphone array based on complementary beamforming", In HSC2001, 67-70.