Mohammed Ismail Elnaggar

Gold nanoplot hot spots simulation and imaging

A study of Local Surface Plasmon Resonance (LSPR) behavior of illuminated elliptical gold nanoplots is presented. We use finite element simulations that show the repartition of the electric field on the surface of an excited gold plot, and corresponding optical spectra. Such results are compared and with experiment (near field optical imaging) and previous work.

Optimal cooperative primary user localization in Cognitive Radio networks

Spectrum sensing is an essential feature of Cognitive Radio (CR) that enables the nodes to determine the availability of the spectrum to be exploited. Recent work on CR propose localization of Primary Users (PUs) which enables CR nodes, also called Secondary Users (SUs), to utilize gray spectrum (occupied by PUs) by limiting their transmission power and hence not causing interference to PUs. Techniques for cooperative localization of PU are inspired from localization in Wireless Sensor Networks. There are a number of algorithms for the enhancement of these techniques in the context of CR. The intended work, presented in this paper, aims to define an algorithm for cooperative PU localization in Cognitive Radio Networks based on an optimal tolerated error. This approach would minimize cooperation overhead while maximizing the probability of detection. The overhead refers to any extra sensing time, delay, energy and operations devoted to cooperative sensing and any performance degradation caused by cooperative sensing [1].