Carrier Aggregation for Underlay Cognitive Radio Wireless Mesh Networks

Cognitive radio (CR) has emerged as a promising technology to solve the tremendous spectrum scarcity problem. Although CR has shown very interesting results, it is still dealing with some drawbacks such as blocking or forced termination events in opportunistic mode and capacity limitation in underlay mode. In this paper carrier aggregation is proposed for wireless mesh networks to enhance the network throughput in underlay CR condition. In the proposed scenario, the primary user uses traditional channels whereas the secondary user aggregates carriers in PU's channels for its transmission. An analytical performance study is carried out which shows the effectiveness of our proposal. With relatively few aggregated carriers per channel, carrier aggregation outperforms single channel and channel aggregation due to its higher detection probability. These results can be used to extend the already well known properties of wireless mesh networks and their applications.