International Journal

Different configurations of leaky-wave antennas (LWAs) based on graphene metasurfaces are studied. The electronic properties of a graphene metasurface in the low THz range are investigated in details in order to discuss the reconfigurability features of the presented structures. Simple exact formulas for evaluating the ohmic losses related to the surface plasmon polariton (SPP) propagation along a

This paper presents a second-order tunable single-ended (unbalanced) bandpass filter (BPF) with continuous 0.4?3-GHz coverage and a tunable balun BPF with continuous 1.1?1.7-GHz coverage for software-defined radio transceivers with the use of band-switchable and radio frequency (RF)-micro-electromechanical systems (MEMS)-tuned resonators. The BPFs are realized with two pairs of RF switches for coa

This paper presents for the first time high-efficiency W-band power amplifiers (PAs), the design of which follows the digital PA (DPA) design concept. Two DPAs with different output networks have been realized: a single-band version (S-DPA) for 95 GHz and a dual-band design (D-DPA) for signal frequencies f of 68 GHz (first band) and 76 GHz (second band), respectively. The PAs are realized as monol

This paper presents design, fabrication, and testing of a palm tree structured monopole antenna for wideband applications. The proposed antenna has a wide impedance bandwidth (?10 dB bandwidth) from 4 to 10.4 GHz. Palm tree antenna of compact size 23 mm × 20 mm is designed and fabricated on an FR4 substrate of thickness 1.6 mm. To validate the design, a mathematical relationship between the parame

A novel design of a compact ultra wideband antenna with triple band-notched characteristics is proposed. Much wider impedance bandwidth (from 2.63 to 13.02 GHz) is obtained by using a star like-shaped radiator and a defected rectangular ground plane and band-notched functions are obtained by attaching L- and I-shaped structure on the ground and a capacitive-loaded loop (CLL) resonator on the patch

Wireless network has been emerged as one of the most promising technologies for sensor-integrated applications so far. The ever-increasing demand in long-term chronic monitoring of vital or essential signals is driving a technology revolution in dealing with critical issues of clinical, healthcare, fitness, and wellness, creating multidisciplinary collaborations to benefit mankind. The voltage-con

The gain properties of an axially slotted cylinder coated with two lossless layers and embedded in a certain lossless background medium have been investigated analytically. The effects of different types of coating layers, i.e. dielectric, magnetic, and Single Negative materials upon the gain characteristics of an axial slot have been discussed. It is observed that if inner layer is either of diel

In this paper, a novel multi-mode resonator is presented, which is formed by cascading several open-circuited transmission line sections with a coupled-line section. Owing to its symmetry, even- and odd-mode analysis methods are applied to analyze its resonance characteristic. Based on this resonator, a microstrip ultra-wide bandwidth (UWB) bandpass filter is designed, fabricated, and measured. Th

In this paper, by using composite right and left handed transmission lines and non-radiating CRLH-TLs, a dual-band 3-way series power divider (SPD) is presented. The proposed dual-band divider is designed and fabricated on an inexpensive FR4 substrate of thickness h = 0.79 mm and a relative dielectric constant of ? = 4.4 to work at 0.915 and 2.440 GHz. Also, in order to improve the isolation chara

A novel ultra-wideband Microstrip bandpass filter using Radial Stub Loaded Resonator (RSLR) and interdigital coupled Lines is presented in this paper. The RSLR and decagonal patch form a resonator named M to create tuneable multiple notches in the passband for the suppression of Wireless Local Area Network systems? interference. To realize sharp roll-off, two adjustable transmission nulls are loca