To solve problems with an input device used for a game machine capable of wireless communications, including difficulty in making a game akin to a real experience due to the impossibility of inputting a change in the posture and position of a player and the impossibility of obtaining a response to a movement even when the player moves his body so as to match a situation of a game.

The reception strength of a signal transmitted from a controller is detected by RSSI40, a body control section 13 computes the distance between the controller and an equipment body from the reception strength of the signal, and reflects it on a game. Therefore, details of the game including the background in the game can be varied in accordance with the position or posture of a player, and the player can feel as if the game is more akin to a real experience and can realistically enjoy the game.