Patent ID: 8274926
Filing Date: 2012-09-25
Classification: H04W

Abstract:
1. A control device which manages a communication terminal within a communication area and communicates with the communication terminal in an active period by using a plurality of predetermined frequency channels, the control device comprising: a first beacon packet generation section that (i) generates a first beacon packet which includes information indicating the active period and one or more candidate channels to which a currently used channel can be changed, and (ii) outputs the first beacon packet; a first beacon packet transmission section that (i) receives the first beacon packet inputted from the first beacon packet generating section, and (ii) transmits the first beacon packet to the communication terminal, at the beginning of the active period; a second beacon packet generation section that (i) determines whether or not a use channel is to be changed, based on a state of communication with the communication terminal in the active period indicated by the transmitted first beacon packet, (ii) generates a second beacon packet which includes information of whether or not the use channel is to be changed, and (iii) outputs the second beacon packet; a second beacon packet transmission section that (i) receives the second beacon packet inputted from the second beacon packet generating section, and (ii) transmits the second beacon packet to the communication terminal, at the end of the active period; and a channel change processing section that (i) receives a signal inputted from the second beacon packet transmission section, (ii) changes, when the second beacon packet generation section determines that the use channel is to be changed, the use channel to a channel different from the currently used channel, after the active period ends and before a next active period starts; and (iii) maintains, when the second beacon packet generation section determines that the use channel is not to be changed, the currently used channel as the use channel.