Underlay cognitive networks operate simultaneously with primary networks satisfying stringent interference constraints, which reduces their transmission power and coverage area. To reach remote destinations, secondary ...

In relay networks, error propagation at the relay nodes degrades the performance of the system. To combat that effect, it has been suggested to implement a reliability threshold at the relay to control error propagation. ...

Spectrum sensing is one of the most essential components of cognitive radio since it detects whether the spectrum is available or not. However, spectrum sensing accuracy is often degraded due to path loss, interference, ...

We consider physical layer security in a multi-input multi-output multi-eavesdropper wiretap channel and present an exact solution to the problem of secrecy rate maximization. A system model with multiple multi-antenna ...

We consider the problem of secrecy rate maximization in a multi-input multi-output multi-eavesdropper (MIMOME) wiretap channel and present an exact solution. A general system model with a multi-antenna eavesdropper and a ...

We propose in this paper a physical layer security (PLS) scheme for dual-hop cooperative networks in an effort to enhance the communications secrecy. The underlying model comprises a transmitting node (Alice), a legitimate ...

We consider a cognitive radio system that consists of primary user, secondary user, and their destinations. The secondary user has a relaying capability, i.e., it transmits the relayed packets from the primary user. Unlike ...

We consider a cooperative relaying system with any number of source terminals, one shared relay, and a common destination. We assume a slotted time division multiple access (TDMA) framework in which each source terminal ...

The anticipated increase in the density of the deployed wireless sensor networks calls for spectrum sharing through unlicensed access to licensed spectrum. The key technology for spectrum sharing in this scenario is cognitive ...

In the next generations of communication systems, resources' scarcity devolves to a more critical point as a consequence of the expected massive number of users to be served. Furthermore, the users' contradicting requirements ...