| 摘要 |
PROBLEM TO BE SOLVED: To provide a structure of an information terminal antenna, which uses specific small power radio electric wave and is small in the gain reduction, even in a small-sized antenna. SOLUTION: In a safety control system of a gas supply, a shielding plate (ground plate) 203 for shielding unwanted radiation of an information process substrate 206 is provided inside an information terminal for communicating with a gas meter with specific low-power radio electric waves, and an antenna 201 and the shielding plate 203 are disposed in the longitudinal direction and into a substantially dipolar shape, and a power is supplied by a power supply part 205. Thus, an information terminal antenna can be realized, which utilizes specific low-power radio, which will not impair the convenience of a user since it has small reduction in gain, even if the antenna 201 is made small-sized.
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