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1 EESTI STANDARD EVS-EN :2013 Methods of measurement for waveguides -- Part 6: Return loss on waveguide and waveguide assemblies

2 EESTI STANDARDI EESSÕNA NATIONAL FOREWORD See Eesti standard EVS-EN :2013 sisaldab Euroopa standardi EN :1997 ingliskeelset teksti. This Estonian standard EVS-EN :2013 consists of the English text of the European standard EN :1997. Standard on jõustunud sellekohase teate avaldamisega EVS Teatajas. Euroopa standardimisorganisatsioonid on teinud Euroopa standardi rahvuslikele liikmetele kättesaadavaks Standard on kättesaadav Eesti Standardikeskusest. This standard has been endorsed with a notification published in the official bulletin of the Estonian Centre for Standardisation. Date of Availability of the European standard is The standard is available from the Estonian Centre for Standardisation. Tagasisidet standardi sisu kohta on võimalik edastada, kasutades EVS-i veebilehel asuvat tagasiside vormi või saates e-kirja meiliaadressile standardiosakond@evs.ee. ICS Standardite reprodutseerimise ja levitamise õigus kuulub Eesti Standardikeskusele Andmete paljundamine, taastekitamine, kopeerimine, salvestamine elektroonsesse süsteemi või edastamine ükskõik millises vormis või millisel teel ilma Eesti Standardikeskuse kirjaliku loata on keelatud. Kui Teil on küsimusi standardite autorikaitse kohta, võtke palun ühendust Eesti Standardikeskusega: Aru 10, Tallinn, Eesti; telefon ; e-post info@evs.ee The right to reproduce and distribute standards belongs to the Estonian Centre for Standardisation No part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, without a written permission from the Estonian Centre for Standardisation. If you have any questions about copyright, please contact Estonian Centre for Standardisation: Aru 10, Tallinn, Estonia; phone ; info@evs.ee

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4 EVS-EN :2013

5 EVS-EN :2013 CEI IEC (Première édition 1995) (First edition 1995) Mesure des pertes de réflexion dans un guide d ondes et des assemblages de guides d onde Measurement of return loss on waveguide and waveguide assemblies CORRIGENDUM 1 Page 4 Page 5 1 Domaine d application 1 Scope Remplacer Replace r = 1 0 (ar/20) r = 10 (ar /20) par: by: r = 10-( a r /20) r = 10-( a r /20) Juillet 2006 July 2006

6 EVS-EN : IEC: Scope MEASUREMENT OF RETURN LOSS ON WAVEGUIDE AND WAVEGUIDE ASSEMBLIES This International. Standard is applicable to the sweep frequency method used for the measurement of return loss on waveguide and waveguide assemblies. Return loss is defined as where u. is the magnitude of the incident wave; ur is the magnitude of the reflected wave. ar = 20 log (ui/ur) db Return loss is related to the reflection coefficient, r, by: r = (ur/ui) r = 10- (ar/20) Fundamentally the method involves measuring the amplitude of the reflected waveguide under test (WUT) input by means of a reflectometer device. The reflected wave can be compared with the total reflected wave under conditions, attenuated by a calibrated attenuator, or it can be compared with wave by means of reflectometer. wave at the short-circuit the incident 2 Equipment A suitable test set-up is shown in figure 1. Alternative equivalent set-ups can be used by agreement between customer and supplier. a) Sweep generator The sweep rate should be slow enough to allow the strip chart recorder to reproduce the peak values faithfully. b) Isolator An isolator or an attenuator is included to prevent reflected waves affecting the output level of the generator. c) Low-pass filter The low-pass filter or the band-pass filter is included to eliminate spurious harmonic frequencies. d) Reflectometer device (coupler or bridge) The effective directivity of the reflectometer (with standard adaptor) should be at least 10 db greater than the value to be measured.