Patent ID: 8619699
Filing Date: 2013-12-31
Classification: H04W

Abstract:
1. A channel switching apparatus of a base station in a cognitive radio system, wherein the base station allocates a slot for data exchange with each of a plurality of terminals in a frequency channel which is not used by an IU (incumbent user), and performs communication, the base station comprising: a channel switching message transmitting unit transmitting a channel switching message requesting to switch to a backup channel when a signal of the IU is sensed in the frequency channel; a backup channel beacon transmitting unit transmitting a beacon frame via the backup channel, wherein the beacon frame comprises allocation information about slots which are in a previous channel and which are respectively allocated to each of the plurality of terminals, wherein the allocation information contains at least one of a modulation scheme, coding information and information about which slot is allocated to which terminal; and a backup channel communicating unit allocating the slot for data exchange with each of the plurality of terminals to the backup channel according to the allocation information, and communicating with each of the plurality of terminals via the backup channel.