PROJECT TITLE :

Joint Subcarrier and Antenna State Selection for Cognitive Heterogeneous Networks With Reconfigurable Antennas

ABSTRACT:

Reconfigurable antennas (RA) offer an rising technology that permits wireless devices to change their antenna states determined by totally different radiation patterns to maximise received signal strength. In this paper, we tend to contemplate multiuser orthogonal frequency-division multiple access cognitive heterogeneous networks (HetNets) and we have a tendency to study the potential edges of using RA in terms of improving the general network capacity. In cognitive HetNets, a secondary network is allowed to share the spectrum with the first network below the condition that the interference level experienced by the first network is below a predetermined threshold. To satisfy this interference constraint, a secondary user (SU) employs an influence management mechanism, which usually limits its transmission power and thus reduces substantially its performance. Moreover, the big variety of users expected for next-generation networks brings dense interference to the secondary network and, as such, even economical interference mitigation and resource allocation techniques can fail in maintaining a suitable performance level for the network. During this work, we consider utilizing RA technology at SUs to act as an additional resource in terms of choosing antenna radiation patterns that improve received signal strength among SUs. This conjointly limits the mutual interference between the secondary and primary networks. We tend to propose a game theoretical framework for jointly choosing the subcarriers likewise as the RA antenna state at every SU that maximizes the capacity of the network whereas meeting the interference target in the primary network. Using potential games that guarantee the existence of a Nash equilibrium, our results show that, by selecting the most effective RA state and subcarriers for each SU, the capacity of the secondary network increases substantially compared to a scenario with standard omni-directional antennas.