Nihad Dib

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—In this paper, a new simple design procedure of multi-frequency unequal split Wilkinson power dividers (WPDs) is presented. The procedure is based on using N-sections of transmission line transformers, instead of the conventional quarter-wave WPD branches, to realize a WPD that operates at N frequencies. Good isolation is achieved by using lumped resistors(More)
The design of N t-section matching transformer operating at N t arbitrary frequencies using the particle swarm optimization (PSO) method is presented. Although analytical methods based on standard transmission line theory can be used in such designs, however, the analysis becomes cumbersome if N t exceeds two, and numerical methods should be used to solve(More)
—Central force optimization (CFO) is a new simple deterministic multi-dimensional search evolutionary algorithm (EA) inspired by gravitational kinematics. This paper evaluates CFO's performance and provides further examples on its effectiveness. A new scheme, the acceleration clipping, is introduced, which enhances CFO's global search ability while(More)
—Central Force Optimization (CFO) is a new multi-dimensional search metaheuristic based on the metaphor of gravita-tional kinematics. In this paper, for the first time, a modified CFO algorithm is applied to the optimal design of multilayer microwave absorbers (for normal incidence) in a specific frequency range. Several numerical examples are presented, in(More)
• Most of the frequency spectrum is allocated to different wireless services • Typically, some of these assigned bands remain idle some of the time • Cognitive Radios (CRs) are gaining attention as an attractive solution to maximizing bandwidth utilization and channel capacity 3 Motivation and Challenges
—In this paper, different topologies of dual-frequency modified 3-way Bagley polygon power dividers are designed and analyzed. Equal split power division is achieved at arbitrary design frequencies. In the first structure, two-section transmission line transformer is used to realize the dual-frequency operation. In the second and third structures,(More)