A new concept is proposed in this paper which can reduce noise radiated from multiple moving sources in the open field by using directional detecting microphones and directional secondary sources. At first, basic experiments concerning on a simple 1-1-1 ANC system were performed in the open field using directional detecting microphones, speakers and error microphones, compared with using non-directional ones. And the directional system was found to have an advantage that it did not create increasing zones around the noise reducing zones. Then, the above directional ANC systems were virtually put side by side along a road and noise reducing effects were predicted by using above experimental data. In this case the ANC filters were fixed and were not affected each other. This prediction proved that the lined ANC systems could reduce noise propagated from moving sources in the open field.
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