Cognitive Radio

This research is the topic of my Masters Thesis conducted under the supervision of Dr. Osvaldo Simeone at NJIT. Cognitive radio is a promising novel technology to improve spectral efficiency by allowing secondary users to exploit underutilized spectrum holes left open by primary users inactivity. We investigate the optimal design of multiuser cognitive radio networks that maximizes the network sum-throughput .

 

Cooperative Communications

This research focuses on the impact of secondary MAC cooperation on the sum-throughput of multichannel cognitive radio networks. In our research we propose One-Shot and Two-Shot cooperation schemes that are shown to provide relevant performance gains in terms of sum-throughput and compare such gains with other non-cooperative schemes.

 

Distributed Spectrum Leasing via Cross Layer Cooperation (DiSC)

This research is a collaborative effort between Ohio State University and NJIT. DiSC enables each primary terminal to "lease" a transmission opportunity to a local secondary terminal in exchange for cooperation (relaying). Secondary users accept the given transmission opportunity only if advantageous in terms of the trade-off between resources used for cooperation and the amount of spectrum leased. The research is devoted to the study of both theory and protocol/ architectural aspects of the DiSC approach. For more info. on this project, click here.

Femtocells

Femtocells promise to increase the number of users served in a given macrocell by creating indoor hotspots connected to the mobile operator network via cheap backhaul links (i.e., the Internet). However, the interference created by the femtocell transmissions may critically impair the performance of the macrocell users. This effect can be potentially alleviated via the so called open-access home base stations when used as relays for the macrocell base station.