A Negative Index Metamaterial to Enhance the Performance of Miniaturized UWB Antenna for Microwave Imaging Applications

Abstract

Abstract:A new, compact planar wideband negative index metamaterial based on a modified split ring resonator (SRR) is studied to enhance performance of ultrawideband antenna. A compact, metamaterial (MTM)-inspired microstrip antenna is presented for microwave imaging system (MIS) application. Two layers of left-handed metamaterial array (2 × 4) of the unit cell are placed on the radiating patch and the ground plane, respectively. Each left-handed metamaterial (LHM) unit cell was constructed by modifying a square split ring resonator (SRR), resulting in negative permeability and permittivity with a stable negative refractive index. The results shows that it has a significant impact on the performance of conventional patch antenna in terms of transmission co-efficient, efficiency and low loss. Compared to antenna without LHM, it is shown that the bandwidth is significantly broadened up to a few megahertz and becomes more convergent leading to the achievement of desired properties for ultra-wideband (UWB) applications leading to microwave imaging. The proposed MTM antenna structure is fabricated on commercially-available, flame-retardant material of size 26 × 22 × 1.6 mm 3 with 4.6 dielectric constants, due to its low cost and convenience for making multilayer printed circuit boards (PCBs). The antenna achieves 3.1 GHz to 10.71 GHz of impedance bandwidth (−10 dB), which covers the full UWB band. The use of double-layer negative index MTM unit cells enhances UWB performance, and the improved radiation efficiency, nearly directional radiation pattern, acceptable gain, stable surface current and negative refractive index make this MTM antenna a suitable candidate for UWB applications.

A metamaterial‐inspired circularly polarized antenna for implantable applications

“…The Nicolson-Ross-Weir (NRW) method is used to characterize the metamaterial properties. 35 The values of the refractive index depend on the values of the permeability and permittivity. The NRW method is mathematically expressed with below equations.…”

Parametric Study and Analysis of Microstrip Patch Antenna with Multiple Slit Positions

“…These advantages lead MIPA's to suitable for advanced wireless applications and 5G communications. These materials having the applications in invisible submarines, negative-index lenses, microwave invisible cloaks, and microwave components [13][14][15]. The array of MIPA's are more suitable for celestial communications, smart transportation systems, wireless power transmission, and other advanced wireless applications [16], owing to these advancements in the design of MIPA's.…”

Feasibility Study of Enhancing Microwave Brain Imaging Using Metamaterials

“…In the microwave spectrum, layers of SRR have been used for biosensing for cancer detection [29,30], magnetic resonance imaging [31,32], and imaging in the near-field [33,34] and far-field [35]. Compact planar MMs based on SRRs have been also used to enhance the performance of antennas for MWI applications [36,37]. At higher frequencies, MM substrates have been proposed to improve the antenna gain and directivity for in-vivo THz biomedical applications [38,39].…”