Patent ID: 9137782
Filing Date: 2015-09-15
Classification: H04W

Abstract:
1. A communication method performed by a communication device, the method comprising: receiving a message including channel information indicating a channel used by at least one external device in a frequency band assigned to the at least one external device, the frequency band including a plurality of channels; generating, by a control unit, candidate available channels in the frequency band assigned to the at least one external device based on the channel information, wherein the candidate available channels comprise at least one of a channel not used by the at least one external device, among a plurality of the channels in the frequency band assigned to the at least one external device; searching, by the control unit, for candidate available channels in a remaining frequency band that is not assigned to the at least one external device; determining, by the control unit, available channels using a combination of the generated candidate available channels and the candidate available channels from the search result; and performing communication through one of the determined available channels, wherein the receiving operation comprises receiving a message including updated channel information from the at least one external device when the channel used by the at least one external device is changed, and the generating operation updates the candidate available channels to at least one of a channel not currently used by the at least one external device based on the received message including the updated channel information, wherein the determining available channels comprises determining an available channel as a channel, from among the candidate available channels, having a longest available time based on information on the candidate available channels which changes over time, and wherein the performing communication comprises performing communication by changing a channel in use to the determined available channel.