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Shielding effectiveness investigations using a reverberation chamber
Thesis (MEng)--Stellenbosch University, 2019.
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| Format: | Thesis |
| Language: | en_ZA |
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Stellenbosch : Stellenbosch University
2019
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| _version_ | 1867613795201843200 |
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| access_status_str | Open Access |
| author | Omollo, Nancy A. |
| author2 | Wiid, P. G. |
| author_browse | Omollo, Nancy A. Wiid, P. G. |
| author_facet | Wiid, P. G. Omollo, Nancy A. |
| author_sort | Omollo, Nancy A. |
| collection | Thesis |
| dc_rights_str_mv | Stellenbosch University |
| description | Thesis (MEng)--Stellenbosch University, 2019. |
| format | Thesis |
| id | oai:scholar.sun.ac.za:10019.1/105859 |
| institution | Stellenbosch University (South Africa) |
| language | en_ZA |
| last_indexed | 2026-06-10T12:41:46.856Z |
| license_str | Other — see source repository |
| provenance_str_mv | Harvested via OAI-PMH from SUNScholar — Stellenbosch University Repository |
| publishDate | 2019 |
| publishDateRange | 2019 |
| publishDateSort | 2019 |
| publisher | Stellenbosch : Stellenbosch University |
| publisherStr | Stellenbosch : Stellenbosch University |
| record_format | dspace |
| source_str | SUNScholar — Stellenbosch University Repository |
| spelling | oai:scholar.sun.ac.za:10019.1/105859 Shielding effectiveness investigations using a reverberation chamber Omollo, Nancy A. Wiid, P. G. Stellenbosch University. Faculty of Engineering. Dept. of Electrical and Electronic Engineering. UCTD Shielding (Electricity) -- Investigations Electromagnetic screens Electromagnetic reverberation chambers Thesis (MEng)--Stellenbosch University, 2019. ENGLISH ABSTRACT: Electromagnetic interference (EMI) is one of the most common problems encountered in radio astronomy observatories. Interaction of electromagnetic (EM) waves from different sources may result in device malfunction due to misinterpretation of the transferred data or information loss. Most equipment and facilities at a radio astronomy observatory are sensitive to this interference. It is therefore important to find a solution to protect these sensitive instruments from damage that may result due to EMI. Many steps have been taken to provide these solutions, including radio frequency campaigns, careful design of electronic systems, radio frequency propagation investigations and shielding. In the latter case, there have been several materials that have been used in shielding at different levels. However, most of the commonly used materials are costly. This project characterizes alternative affordable commercial materials that can be used for shielding. Characterization of these materials is done using a reverberation chamber and specific to the nested reverberation chamber technique for repeatability purposes. The measurements are done in frequency domain (FD) and validated using time domain (TD) methods. The two sets of measurements are carried out in two different reverberation chambers with different physical dimensions and characteristics. The TD measurement is investigated for measurement time speed-up. Measurement in TD is done using the real time analyser (RTA), which is a high dynamic range instrument with a measurement bandwidth of up to 3 GHz. A few of the investigated materials showed effective shielding. The absorbing sheet material and the radiant barrier roofing material showed shielding values of at least 30dB and above. These cheaper materials are therefore recommended for use at the Square Kilometre Array (SKA) buildings for additional shielding. AFRIKAANSE OPSOMMING: Elektromagnetiese inmenging (EMI) is een van die hoofprobleme wat sterrekundiges en ingenieurs in die radio-sterrekunde-observatoria ondervind. Interaksie van elektromagnetiese (EM) golwe uit verskillende bronne kan apparaatfout, datavervorming of dataverlies veroorsaak. Die meeste toerusting en fasiliteite by 'n radio-sterrekunde-observatorium is sensitief vir hierdie inmenging. Dit is dus belangrik om 'n oplossing te vind om hierdie sensitiewe instrumente te beskerm teen skade wat mag voortspruit uit EMI. Daar is baie stappe gedoen om hierdie oplossings te voorsien, insluitend radiofrekwensie veldtogte, versigtige ontwerp van elektroniese stelsels, ondersoek van radiofrekwensievoortplanting en afskerming. In laasgenoemde geval was daar verskeie materiale wat op verskillende vlakke in afskerming gebruik is. Die meeste van die algemeen gebruikte materiale is egter duur. Hierdie projek kyk na die karakterisering van alternatiewe bekostigbare kommersiële materiaal wat vir afskerming gebruik kan word. Karakterisering van hierdie materiale word gedoen met behulp van 'n weerkaats-kamer en spesifiek vir die geneste weerkaats-kamer tegniek vir herhaalbaarheid doeleindes. Die metings word in frekwensiedomein (FD) gedoen en valideer met behulp van tyddomein (TD) metodes. Die twee stelle metings word uitgevoer in twee verskillende weerkaats-kamer met verskillende fisiese dimensies en eienskappe. Die TD-meting word ondersoek vir metingstyd versnelling. Meting in TD word gedoen met behulp van die Real Time Analyzer (RTA), wat 'n hoë dinamiese bereik instrument met 'n meting bandwydte van tot 3 GHz is. 'n Paar van die materiale wat ondersoek is, het effektiewe afskerming getoon. Die absorberende plaatmateriaal en die stralingsdempende dakmateriaal het skermwaardes van minstens 30 dB en hoër vertoon. Hierdie materiaal kan aanbeveel word by SKA geboue vir bykomende afskerming teen lae koste. 2019-02-22T06:33:10Z 2019-04-17T08:16:03Z 2019-02-22T06:33:10Z 2019-04-17T08:16:03Z 2019-04 Thesis http://hdl.handle.net/10019.1/105859 en_ZA Stellenbosch University 107 pages : illustrations application/pdf Stellenbosch : Stellenbosch University |
| spellingShingle | UCTD Shielding (Electricity) -- Investigations Electromagnetic screens Electromagnetic reverberation chambers Omollo, Nancy A. Shielding effectiveness investigations using a reverberation chamber |
| title | Shielding effectiveness investigations using a reverberation chamber |
| title_full | Shielding effectiveness investigations using a reverberation chamber |
| title_fullStr | Shielding effectiveness investigations using a reverberation chamber |
| title_full_unstemmed | Shielding effectiveness investigations using a reverberation chamber |
| title_short | Shielding effectiveness investigations using a reverberation chamber |
| title_sort | shielding effectiveness investigations using a reverberation chamber |
| topic | UCTD Shielding (Electricity) -- Investigations Electromagnetic screens Electromagnetic reverberation chambers |
| url | http://hdl.handle.net/10019.1/105859 |
| work_keys_str_mv | AT omollonancya shieldingeffectivenessinvestigationsusingareverberationchamber |