To obtain a small-sized antenna that has an outer diameter smaller in comparison the wavelength, a simple structure and provides radiation in a multi-radiation direction.

This antenna has a main radiation element in the shape of circle whose radius is (a) an outer size is 1/2 π of the wavelength or below that has an n-turn winding in radius (s) made of a radiation wire 1 which is a linear conductor L in length (or ribbon conductor). The main radiation element is energized from its tap, and a capacitor 3 connected in series with a conductor wire 7 is used for matching with a feeder 4.