| 摘要 |
PROBLEM TO BE SOLVED: To provide an inexpensively manufacturable radio wave arrival direction detection device having a simple circuit configuration compared with conventional examples. SOLUTION: This radio wave arrival direction detection device receives a radio wave radiated from a transmission device placed separately from the detection device, and detects the radio wave arrival direction. Two receiving antennas 1-1, 1-2 juxtaposed on mutually different positions are supported by a support substrate 20 rotatably around the rotation axis O provided on the support substrate 20, and when the support substrate 20 is rotated, the frequency difference between two received signals relative to the same radio wave received by the receiving antennas 1-1, 1-2 is operated by a frequency comparator 9. When the operated frequency difference becomes substantially zero at the transition time from positive to negative, a light-emitting diode 12 provided on a straight line 40 passing the rotation axis O and the positions of the receiving antennas 1-1, 1-2 on the support substrate 20 is switched to the ON state and allowed to emit light, and the radio wave arrival direction is reported by using a Doppler effect. COPYRIGHT: (C)2004,JPO
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