Ultra wideband tightly coupled reflectarray antenna

Download

mutlukoldas_final_thesis.pdf

Date

2022-2-08

Author

Koldaş, Mutlu

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

285
views

986
downloads

In this thesis, an ultra wideband tightly coupled dipole reflectarray antenna is de signed, fabricated, and measured. This reflectarray consists of a wideband log-periodic dipole array feed antenna and a reflecting surface. The unit element of the reflecting surface is a tightly coupled overlapping bowtie dipole attached with a delay line to approach ultra wideband aim. Infinite array approach and Floquet port excitation ap plied in unit cell simulations to obtain reflection phase curves versus the length of the delay line of the dipole. The reflected beam can be adjusted to radiate in a particu lar direction by arranging the delay line lengths of the tightly coupled dipoles at the design step. A MATLAB code is developed with GUI to construct a full reflecting surface after deciding the delay line lengths with respect to input parameters. The code automatically constructs a reflecting surface in CST Studio Suite where the full wave simulations are executed. Then, a 5×20 reflectarray with the beam directed 30 degrees from the broadside is designed and fabricated. Design is validated by the measurements that the fabricated reflectarray is capable to operate from 4 GHz to 10 GHz.

Subject Keywords

Reflectarray, Ultra wideband, Tightly coupled array, Overlapping bowtie dipole, Log-periodic dipole array

URI

https://hdl.handle.net/11511/96317

Collections

Graduate School of Natural and Applied Sciences, Thesis

Suggestions

OpenMETU
Core

Design of a dual polarized low profile antenna for microwave brain imaging Üçel, Kaan; Alatan, Lale; Department of Electrical and Electronics Engineering (2022-5-9) In this thesis, a low profile, low cost, wide band (0.9-2GHz) dual linearly polarized printed dipole antenna is designed to be used in microwave brain imaging systems. Dual polarization feature offers superior data acquisition through polarization diversity for better image quality. Starting from a simple printed dipole, antenna structure is modified step by step to meet these design requirements. Since a conductive surface in close vicinity of the antenna affects antenna performance, in order to obtain uni...
Metamaterial absorber-based multisensor applications using a meander-line resonator AKGÖL, OĞUZHAN; ALTINTAŞ, OLCAY; Dalkilinc, Elif Eda; ÜNAL, EMİN; KARAASLAN, MUHARREM; Sabah, Cumali (2017-08-01) A metamaterial (MTM) absorber-based multifunctional sensor is numerically and experimentally realized using meander-line resonators. The proposed sensor device can be used to measure pressure, density, and humidity with perfect signal absorption characteristics at the frequency range of X band. The structure consists of a sensor layer sandwiched between two dielectric slabs. The sensor layer is used to detect unknown environmental parameters with respect to the electromagnetic responses of the material unde...
Wideband omnidirectional and sector coverage antenna arrays for base stations Alatan, Lale (2018-01-01) By using parallel strip line fed printed dipole antennas as array elements, an omnidirectional antenna array and a wide angle sector coverage array operating in octave band are designed. A maximum deviation of ±1.25 dB from the omnidirectional pattern is achieved for the omnidirectional array, and the average gain of the antenna was measured as being 5 dB in the 1.35–2.7GHz band. For the sector coverage array, a special reflector design is utilized to maintain a half power beam width of around 115◦ with a s...
Development of an ultra wide band (UWB) array antenna Ceylan, Hasan Akın; Aydın Çivi, Hatice Özlem; Department of Electrical and Electronics Engineering (2022-4) Demand for ultrawideband antenna arrays in telecommunications, space and airborne platforms, RADAR applications and MIMO systems, etc. is rising consistantly. A modern approach to develop an ultrawideband array is to utilize the mutual coupling between array elements. Even though individual elements are of narrowband characteristic in isolated form, they gain ultrawideband performance in array configuration under strong mutual coupling. In this work, an ultrawideband tightly coupled dipole array antenna is ...
Investigation of tightly coupled arrays for wideband applications Arda, Kaan; Dural Ünver, Mevlüde Gülbin; Department of Electrical and Electronics Engineering (2020-10) This thesis aims to provide in depth research on tightly coupled dipole arrays to be used in ultrawideband apertures applications. First, operation principles of tightly coupled dipole arrays are investigated. Starting from the Wheeler’s current sheet aperture concept, some calculations on bandwidth and impedance concepts are conducted. B.A. Munk’s addition to the concept, use of capacitive elements between adjacent dipoles, are introduced. Array unit cell is modeled using equivalent circuit approach,...

Citation Formats

M. Koldaş, “Ultra wideband tightly coupled reflectarray antenna,” M.S. - Master of Science, Middle East Technical University, 2022.