The Antenna Tower is the central building on the island of Digitoll. This is where new Denpa Men are caught via the 3DS's camera, similar to the Augmented Reality but without the cards. A privacy mode is optional if the 3DS is used in a public environment and the background will turn into a squared turquoise layout.
The tower is described in the game as "A device to catch Denpa Men.". It's appearance is that of a lighthouse with several antennas at the top.
The device is controlled like a camera, moving the 3DS around to aim a reticle at the middle of the screen and pressing the A button to launch a net that captures the Denpa Men.