Antenna

摘要

An antenna is provided to improve the gain and to eliminate various negative effects caused by a surrounding environment in which the antenna is mounted, such as the effects caused by neighboring metal plates and the like, while providing an antenna structure to facilitate its assembly into various communication devices. The antenna A emitting radio waves at a center frequency has an antenna main body 1 and a grounding line section 2 connected to the ground-side of the coaxial cable C for supplying power to the antenna main body 1. The grounding line section 2 starts from a reference point O and extends in a loop so as to surround the antenna main body 1, and portions of the conductor line are severed so as to provide a first end terminal Q1 and a second end terminal Q2 so that the length of the conductor line from the reference point O to the first end terminal Q1 corresponds to one quarter of a wavelength of the center frequency or its integral multiple.