To provide a contrivance whereby information entered by a user is not missing when a channel of a mobile phone using a wireless channel is interrupted or when the channel is in use.

The user enters information by using an information entry means, uses a communication means to transmit the information to an exchange, receives information by the communication means and an information output means outputs the information for the user. When a channel for the communication means is interrupted, an information save means saves the entered information to a memory, and when the channel is connected again, the user transmits the saved information to the exchange by using the communication means through a re-transmission means. A channel switch means in the exchange connects wireless communication apparatuses. When the exchange detects channel interruption, the exchange uses an information save means to save the received information to a memory, and when the exchange detects re-connection of the channel, a re-transmission means of the exchange uses the communication means to transmit the saved information to the wireless communication apparatus.