| 摘要 |
<p>PROBLEM TO BE SOLVED: To precisely detect the direction to an electromagnetic wave generating source, such as a thunderbolt, earthquake, etc., over a wide frequency range. SOLUTION: When an electromagnetic wave RW1 caused by a thunderbolt, etc., and having a strong magnetic-field signal strength and a high frequency arrives from the horizontal direction, output voltages are respectively generated across the first and fourth terminals 1 and 4 of orthogonal first and second antennas 10 and 20 and across the second and fifth terminals 2 and 5 of the antennas 10 and 20 which are the intermediate terminals of the antennas 10 and 20. From the output voltages, the arriving azimuth of the electromagnetic wave RW1 can be measured. When another electromagnetic wave RW2 caused b an earthquake, etc., and having a low magnetic-field signal strength and a weak frequency arrives from the horizontal direction, output voltages are respectively generated across the first and fourth terminals 1 and 4 and across the third and sixth terminals 3 and 6 of the antennas 10 and 20. From the output voltages, the arriving azimuth of the wave RW2 can be measured.</p> |
