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Full scale low-cost ultra wide band antenna for SKA low frequency array

Thesis (MScEng)--Stellenbosch University, 2013.

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Bibliographic Details
Main Author: Schoeman, Dewald Hermanus
Other Authors: De Villiers, D. I. L.
Format: Thesis
Language:en_ZA
Published: Stellenbosch : Stellenbosch University 2013
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access_status_str Open Access
author Schoeman, Dewald Hermanus
author2 De Villiers, D. I. L.
author_browse De Villiers, D. I. L.
Schoeman, Dewald Hermanus
author_facet De Villiers, D. I. L.
Schoeman, Dewald Hermanus
author_sort Schoeman, Dewald Hermanus
collection Thesis
dc_rights_str_mv Stellenbosch University
description Thesis (MScEng)--Stellenbosch University, 2013.
format Thesis
id oai:scholar.sun.ac.za:10019.1/80084
institution Stellenbosch University (South Africa)
language en_ZA
last_indexed 2026-06-10T12:41:54.752Z
license_str Other — see source repository
provenance_str_mv Harvested via OAI-PMH from SUNScholar — Stellenbosch University Repository
publishDate 2013
publishDateRange 2013
publishDateSort 2013
publisher Stellenbosch : Stellenbosch University
publisherStr Stellenbosch : Stellenbosch University
record_format dspace
source_str SUNScholar — Stellenbosch University Repository
spelling oai:scholar.sun.ac.za:10019.1/80084 Full scale low-cost ultra wide band antenna for SKA low frequency array Schoeman, Dewald Hermanus De Villiers, D. I. L. Stellenbosch University. Faculty of Engineering. Dept. of Electrical and Electronic Engineering. Directive antennas Log-periodic-dipole-array (LPDA) Ultra wide band (UWB) Zig-zag antennas Dissertations -- Electronic engineering Theses -- Electronic engineering Square Kilometre Array (SKA) Thesis (MScEng)--Stellenbosch University, 2013. ENGLISH ABSTRACT: This thesis is about the design, simulation and measuring of ultra wide band antennas for use in the Square Kilometre Array (SKA). The SKA is a radio astronomy project with one of the aims of detecting hydrogen particles in deep space. Several thousand antennas over a wide band of frequencies are needed to receive the radiation from these particles. This motivates the need for a low-cost ultra wide band antenna with the focus on the low frequency part of the SKA. In this thesis we present two design strategies: The first design strategy is for a printed LPDA on a substrate and design curves are generated. A scale model was built and measurements did not correlate with simulation results. This is due to manufacturing tolerances and assembly of the pyramidal structure. The second design strategy is for a full scale zig-zag antenna and design curves were also generated. The aim here is to produce a low-cost prototype by using brazing rods for the wire structure and mount it on a wooden frame. A full scale model was built and measurements on the roof produced much interference for the radiation pattern, but the reflection coefficient was good. We suggest doing measurements in an interference free environment in order to achieve the needed results. To conclude we suggest using the zig-zag antenna for the SKA. Some issues do however need more attention as the transformer has some losses, the cross polarisation is probably not good enough and the beamwidth does not reach the specification. We demonstrated a low cost prototype and there is the possibility of low-cost large scale manufacturing but this needs to be addressed. This has however not been analysed as many factors for large scale manufacturing are very difficult to predict beforehand and lies outside the scope of this thesis. AFRIKAANSE OPSOMMING: Hierdie tesis gaan oor die ontwerp, simulasie en opmeting van ultrawyebandantennas vir gebruik in die SKA ("Square Kilometre Array"). Die SKA is ’n radioastronomie projek met die doel om waterstof partikels op te spoor in die ruimte. Duisende antennas wat oor ’n wye band van frekwensies strek is nodig om die energie van die partikels op te vang. Hieruit is daar ’n aanvraag vir lae-koste ultrawyebandantennas met die fokus op die lae frekwensie deel van die SKA. In hierdie tesis word twee ontwerpstrategieë voorgestel: Die eerste ontwerpstrategie is vir ’n gedrukte logaritmies periodiese dipool reeks (LPDR) op ’n substraat tesame met ontwerpskurwes wat gegenereer word. ’n Skaal model is gebou en die gemete resultate stem nie ooreen met die simulasie nie. Dit kan toegeskryf word aan vervaardigingstoleransies en die aanmekaar sit van die piramide struktuur. Die tweede ontwerpstrategie is vir ’n vol skaal sigsag ("zig-zag") antenna met ontwerpskurwes wat ook gegenereer word. Die doel is om ’n lae-koste prototipe te bou deur sweissoldeerdraad te gebruik vir die draadstruktuur en dan op ’n hout raam te plaas. ’n Vol skaal model is gebou en metings op die dak het baie interferensie veroorsaak vir die stralingsveld, maar tog was die weerkaatskoëffisient goed. Ons stel voor om die metings te herhaal in ’n steuringvrye omgewing om sodoende die korrekte resultate te verkry. Om af te sluit stel ons voor om die sigsag antenna vir die SKA te gebruik. Sekere kwessies soos die transformator wat verlieserig is, die kruispolarisasie wat moontlik nie goed genoeg is nie en die bundelwydte wat nie die spesifikasie haal nie moet nog aandag geniet. Ons het ’n lae-koste prototipe gedemonstreer en daar is die moontlikheid om dit op grootskaalse vervaardiging ook goedkoop te doen, maar dit moet nog uigesorteer word. Dit was wel nie geanaliseer nie, siende dat vele faktore ’n rol speel by grootskaalse vervaardiging wat uiters moeilik is om voor die tyd te voorspel en buite die omvang van die tesis lê. 2013-02-22T13:54:14Z 2013-03-15T07:34:11Z 2013-02-22T13:54:14Z 2013-03-15T07:34:11Z 2013-03 Thesis http://hdl.handle.net/10019.1/80084 en_ZA Stellenbosch University 80 p. : ill. application/pdf Stellenbosch : Stellenbosch University
spellingShingle Directive antennas
Log-periodic-dipole-array (LPDA)
Ultra wide band (UWB)
Zig-zag antennas
Dissertations -- Electronic engineering
Theses -- Electronic engineering
Square Kilometre Array (SKA)
Schoeman, Dewald Hermanus
Full scale low-cost ultra wide band antenna for SKA low frequency array
title Full scale low-cost ultra wide band antenna for SKA low frequency array
title_full Full scale low-cost ultra wide band antenna for SKA low frequency array
title_fullStr Full scale low-cost ultra wide band antenna for SKA low frequency array
title_full_unstemmed Full scale low-cost ultra wide band antenna for SKA low frequency array
title_short Full scale low-cost ultra wide band antenna for SKA low frequency array
title_sort full scale low cost ultra wide band antenna for ska low frequency array
topic Directive antennas
Log-periodic-dipole-array (LPDA)
Ultra wide band (UWB)
Zig-zag antennas
Dissertations -- Electronic engineering
Theses -- Electronic engineering
Square Kilometre Array (SKA)
url http://hdl.handle.net/10019.1/80084
work_keys_str_mv AT schoemandewaldhermanus fullscalelowcostultrawidebandantennaforskalowfrequencyarray