Abstract: A flat antenna structure is obtained by sequentially stacking a first foam agent on a dielectric earth conductor substrate, a radiating element substrate for radiating an electromagnetic wave on the first foam agent, a second foam agent on the radiating element substrate, and a slot substrate. The slot substrate is formed with plural parasitic elements and rectangular slots for finally radiating the electromagnetic wave from the radiating element substrate and for blocking unnecessary radiation of the electromagnetic wave from the radiating element substrate on the second foam agent. This structure enhances the efficiency of the antenna and allow the antenna to selectively receive two adjacent satellite broadcasts.