| 摘要 |
<P>PROBLEM TO BE SOLVED: To solve the problems of a cost and a shape when an antenna is surrounded by a shield material in order to make differences in reception sensitivity in the front-rear direction of the bar antenna since it is difficult to arbitrarily control the directivity of the antenna in an induction electromagnetic field, wherein communication is carried out in an induction electromagnetic field since the wavelength is extremely long compared with a communication distance in the case of low-frequency band radio communication in a short distance such as keyless entry or smart entry, although communication is carried out in the area of a radiation electromagnetic field in the case of high-frequency band communication even if communication is in a short distance since the wavelength is short. Ž<P>SOLUTION: The bar antenna has a coil wound around a magnetic core. The magnetic core has a leg portion projecting from a center part of a rod-like core and arm portions at both ends of the rod-like core. The bar antenna is characterized in that the distal ends of the arm portions are inclined in the same direction as the leg portion. Ž<P>COPYRIGHT: (C)2010,JPO&INPIT Ž
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