ANTENNA DEVICE

摘要

PROBLEM TO BE SOLVED: To provide an antenna device capable of suppressing deteriorated communication performance while maintaining a size and power consumption.SOLUTION: An electronic key is specified to be an antenna device having both a UHF antenna 15 and an HF antenna 16. The HF antenna 16 includes a loop antenna enclosing the overall UHF antenna 15. Namely, the UHF antenna 15 is disposed in overlay with the HF antenna 16. Filters 17 that resonate at RF transmission using an UHF band radio wave are inserted turn-by-turn. The filters 17 are disposed in alignment on a straight line that perpendicularly intersects each turn.