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In this article, an ultra‐wideband (UWB) topology optimized frequency selective surface (FSS) is introduced as a reflecting layer, to maximize the gain and overall performances of an UWB monopole antenna. The single Rogers RO4350B‐based FSS layer is synthesized using an automated system, based on an interface bridged between CST Microwave studio and Matlab, and optimized using a binary genetic algorithm. First, the FSS unit cell foot print needs to be as small as possible, while covering a wider frequency range, and to achieve these performances, the proposed genetic algorithm synthesizing system achieved an FSS unit cell with only 0.1 λ × 0.1 λ at the lower‐end frequency, covering a bandwidth of 2.9–14.5 GHz. Polarization independence is achieved also, due to the four‐folded symmetry imposed on the FSS unit cell. The proposed antenna is designed on a Rogers RO4350B substrate, and backed at a distance of 18.74 mm by an FSS structure. The fabricated prototype shows a bandwidth of 3.1–13.9 GHz, and an excellent maximum peak gain of 9.7 dBi, with an improvement of 3.41 dBi cross the UWB spectrum (from 3.7 to 7.11 dBi), and in good agreement with the simulation results, which made the proposed design a promising candidate for UWB applications requiring high gain, such as ground‐penetrating radar, and microwave radiology imaging (MRI) systems.

A low-profiled microstrip patch antenna for application in the 5G wireless communication systems is backed by a reflecting layer based on an optimized artificial magnetic conductor (AMC) to enhance the gain and the front-to-back ratio. The design and analyses process were carried out using the full-wave commercial simulator CST Microwave Studio in parallel with Matlab, using the embedded CST to Matlab VBA-based interface to create an automated simulation environment and to design both a conventional antenna and the proposed one. A genetic algorithm (GA) is used to optimize the AMC reflecting layer to achieve maximum gain and front-to-back ratio around the frequency band of interest. The results yield an important enhancement in the peak gain and front-to-back ratio, alongside a low side-lobe level (SLL) due to the successful surface waves suppression, thus making this antenna design a good candidate for future wireless communication systems.

In this paper, a compact and highly sensitive refractive index plasmonic sensor, with a metal-insulator-metal waveguide coupled with a notched hexagonal ring resonator and the stub is proposed. Structural parameters of the sensor have a key role in the sensor's sensitivity and transmission spectrum, which are investigated using the finite-difference time-domain method embedded in the commercial simulator R-Soft. The results yield a linear link with the refractive index of the material under testing and its wavelength resonances. Moreover, the maximum linear sensitivity is S = 2547 nm/RIU, its corresponding sensing resolution is 3.92 × 10 −6 RIU. Therefore, this sensor can be implemented in high-performance nano-sensors and biosensing devices. In this proposed structure, the positions of transmission peaks can be easily manipulated, by adjusting the length and width of the stub.