Patent ID: 8457646
Filing Date: 2013-06-04
Classification: H04W

Abstract:
1. A channel exchange method of a requesting Base Station (BS) that requests a neighboring BS to exchange a channel in a Cognitive Radio (CR) based communication system, the method comprising: receiving a channel advertisement message from a neighboring BS; defining an active set of channels and a candidate set of channels, wherein the active set of channels comprises one or more channels actively used by the requesting BS and the candidate set of channels comprises one or more channels reserved for use by the requesting BS when one of the channels in the active set becomes unavailable; detecting a primary user in the requesting BS, wherein the primary user is using a first channel; when the first channel is in the active set of channels, initiating an exchange of the first channel for a second channel with the neighboring BS by sending a channel exchange request message to the neighboring BS, the channel exchange request message comprising at least one of a neighbor BS Identifier (ED), a requesting BS ID, channel information for the channel exchange at the requesting BS, and channel information exchangeable at the neighboring BS; receiving a channel exchange response message from the neighboring BS in response to the channel exchange request message; and determining whether to execute a channel exchange process to the neighboring BS based on information in the received channel exchange response message, and sending a channel exchange reply message indicative of the determination result, wherein the channel exchange process comprises moving the first channel from the active set to an inactive set of channels for the requesting BS, switching a third channel from the candidate set to the active set, and adding the second channel to the candidate set.