| 摘要 |
<P>PROBLEM TO BE SOLVED: To realize low power consumption at the time of waiting and operation high speed communication in a communication system comprising a main communication device and a sub-communication device. <P>SOLUTION: A control means in the main communication device performs communication with the sub-communication device through a first communication means when starting communication. When a decision is made that the main communication device can communicate with the sub-communication device, a second communication means in the main communication device is activated to transmit a signal for activating the second communication means in the sub-communication device. Subsequently, communication is performed using the second communication means and the control means in the sub-communication device performs communication through the first communication means. When the signal for activating the second communication means is received from the main communication device, the second communication means is activated. Upon ending communication, the control means in the main communication device transmits an operation stop signal of the second communication means to the sub-communication device using the first or second communication means and stops operation of the second communication means in the main communication device. Upon receiving the operation stop signal of the second communication means, the control means in the sub-communication device stops operation of the second communication means. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
