PURPOSE: To extend the radiation band of a radiating element with a relatively simple and economical constitution and to improve the compatibility between the radiating element and a feeder with respect to the plane antenna used as an antenna for satellite broadcast reception or satellite communication, an antenna for general communication or a radar, an antenna of a single element having a wide-angle directivity for mobile communication, etc.

CONSTITUTION: The Q value of an MSA radiating element 3 is reduced to extend the band of matching to a feed line 5 by the simple structure where an outer high-dielectric constant dielectric layer 7 and an inner low-dielectric constant dielectric layer 7' whose thickness is 1/4 effective wavelength are laminated on the radiating element 3, and the band of the axial ratio indicating the circular polarization characteristic is extended in the case of a circularly polarized wave radiating element.