In a business wireless system, a group including a plurality of terminal devices is formed and communication is performed by using at least one base station device to assign a channel to each group. A transmission unit uses a channel assigned by the base station device to a first group for transmission. An authentication processing unit authenticates a user using the terminal device. A selection unit selects one of a second group that only the terminal devices for which the authentication process is completed can subscribe to, and the first group, when the authentication process is completed. When the second group is selected, the transmission unit the channel assigned by the base station device to the second group for transmission.