Gain enhancement of the ultra-wideband tapered slot antenna using broadband gradient refractive index metamaterial

Abstract

In this article, a broadband gradient refractive index (GRIN) metamaterial is designed and used to enhance the gain of the tapered slot antenna (TSA). The proposed GRIN is implemented using nonresonant parallel‐line unit cell with different refractive index values. GRIN lens are placed in front of the tapered slot direction in the direction of x‐axis. The designed GRIN metamaterials have broad bandwidth (2‐12 GHz) characteristics due to the nonresonant parallel‐line elements which is suitable for the ultra‐wideband frequency band. The measurement results indicates that the radiated beam becomes more directive with narrow beam width. The measured reflection coefficient is below −10 dB over the frequency bandwidth of 3‐11 GHz. The peak gain of TSA is obtained up to 14 dB at 10 GHz using GRIN lens.

Dielectric loaded directive Vivaldi antenna considering dispersion in near and far field

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“…2 Due to its ultra-wide band frequency response, the Vivaldi antenna is being used for many microwave systems. [3][4][5][6][7] However, the efficient transmission and reception are only possible for high signal to noise ratio, less ringing, pulse spreading, less polarization mismatch, low dispersion, and distortion in received signal. 4,8 The directivity of the conventional Vivaldi antenna is one of its limitations which is low as compare to horn antennas.…”

Effect of dielectric materials on integrated lens antenna for millimeter wave applications

“…In the first category, the antenna and lens are either in direct contact with each other customarily, known as ILA or they may be far apart commonly known as off body fed . In second category, the refractive index of lens can be constant, stepped or non‐uniform .…”

Wideband beam-steerable configuration of metasurface loaded slot antenna

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