Design and realization of a broad band antenna loaded with a metamaterial-inspired lens for subsurface microwave imaging applications

Yeşilyurt, Ömer
Ultra-wideband antennas are critical sensors for microwave imaging. In this work, radiation performance of an antipodal Vivaldi antenna is enhanced by using a broadband metasurface lens structure in 1-6 GHz bandwidth. Radiation pattern for the lens integrated antenna is more directive due to electromagnetic properties of the metasurface lens. In order to create such a lens, electrically responsive metamaterial unit cells with high effective permittivity values are designed. As we want to obtain a broadband antenna performance, metamaterial unit cell dimensions are adjusted to avoid the resonance regions of the metasurface over the desired operation bandwidth of the antenna. Overall lens structure is etched over the same substrate containing the antipodal Vivaldi antenna resulting in a compact design. Far-field radiation patterns indicate that more directive beam is radiated from the antenna with metasurface lens. Measurement and simulation results show that directivity is increased considerably without affecting the efficiency characteristics of the antenna. Microwave image of a shallowly buried conducting object is constructed by using with metasurface integrated antenna and also by using the conventional antipodal Vivaldi antenna as sensors. Two-dimensional microwave images are constructed by using the total energy values of the time signals measured at each spatial sampling point. Due to its more directive radiation pattern, the images obtained by the antenna with metasurface lens are observed to have better resolution.


Design of an active microstrip array using a microwave circuit simulator
Demir, S; Toker, Canan; Hizal, A (1997-02-26)
An active antenna array design and simulation of this design with a microwave circuit simulator are presented. This active antenna array is a TV receive only (TVRO) antenna operating at 10 GHz. It is a 8x4 array of rectangular microstrip patch antennas. Eight low noise pHEMTs are placed in the antenna. Passive antenna characteristics are usually obtained by analytical techniques or using special softwares for this purpose. The numerical representation as well as the nonreciprocal nature of the active device...
Design and analysis of ultra-wideband (UWB) printed monopole antennas of circular shape
Karadağ, Serkan; Aydın Çivi, Hatice Özlem; Department of Electrical and Electronics Engineering (2017)
This study proposes three microstrip line fed circular monopole antennas with ultra-wideband (UWB) characteristics, improved omnidirectional radiation pattern and WLAN (5 GHz-6 GHz) band notched characteristics for wireless and mobile communication systems. In this thesis, first, a microstrip line fed ultra-wideband ring monopole antenna with improved omnidirectional radiation pattern is designed, fabricated and measured. Two corners are tapered on the ground plane for increasing impedance bandwidth. In ord...
Analysis of spherical-rectangular printed antennas and antenna arrays using cavity model
Demir, Oğuz; Dural Ünver, Mevlüde Gülbin; Department of Electrical and Electronics Engineering (2017)
Printed antennas are commonly used since these antennas are preferred in many applications due to their advantageous properties. In order to employ these antennas in such applications, a thorough investigation and analysis are generally required. Although this can be implemented with fully numerical methods for the sake of high accuracy, the complex calculations required in the process lead to heavy computational load, hence generally demands high quality simulation software. In this thesis, the spherical-r...
Design of series-fed printed slot antenna arrays excited by microstrip lines
İncebacak, Mustafa; Alatan, Lale; Department of Electrical and Electronics Engineering (2010)
Series-fed printed slot antenna arrays excited by microstrip lines are low profile, easy to manufacture, low cost structures that found use in applications that doesn’t require high power levels with having advantage of easy integration with microwave front-end circuitry. In this thesis, design and analysis of microstrip line fed slot antenna arrays are investigated. First an equivalent circuit model that ignores mutual coupling effects between slots is studied. A 6-element array is designed by using this e...
Design and Analysis of a Cylindrical Array of Stripline Fed Slot Antennas For On-Board Telemetry Applications
Ozcan, Mustafa; Aydın Çivi, Hatice Özlem (2016-07-01)
In this study, cylindrical array of stripline fed rounded bow-tie slot antennas is designed to be used for avionics applications. The array element is fed by a T shaped strip line. Shape of the slot is modified from rectangular to rounded bow-tie to provide sufficient bandwidth for telemetry application. Furthermore, vias are placed around slots to prevent unwanted parallel plate modes of stripline structure. It is observed that, location of vias is critical in the design of the antenna. Thus, parametric st...
Citation Formats
Ö. Yeşilyurt, “Design and realization of a broad band antenna loaded with a metamaterial-inspired lens for subsurface microwave imaging applications,” M.S. - Master of Science, Middle East Technical University, 2019.