Directivity controllable antenna and antenna unit using the same

An antenna unit including an antenna with a directivity, comprising:

• a ground conductor;
• at least two power supply sections placed on a surface of the ground conductor;
• at least two antenna elements connected one-to-one to the power supply sections;
• a top conductor opposed to the ground conductor across the antenna elements;
• side conductors surrounding a space including the antenna elements, being located apart from the antenna elements, and forming, together with the top conductor and the ground conductor, an antenna box having at least two openings;
• a power supply control section for controlling signals passing through between an external connecting terminal and the power supply sections;
• and
• a radio circuit for supplying the antenna connecting terminal with a radio signal received from an antenna control device externally provided, and transmitting a radio signal output from the antenna connecting terminal to the antenna control device.