ISO INTERNATIONAL STANDARD 17497-2 First edition 2012-05-15 Acoustics Sound-scattering properties of surfaces - Part 2: Measurement of the directional diffusion coefficient in a free field Acoustique - Propriétés de dispersion du son par les surfaces Partie 2: Mesurage du coefficient de diffusion directionnel en champ libre Reference number ISO 17497-2:2012(E) LSO @ ISO 2012 Not for Resale ISO 17497-2:2012(E) COPYRIGHTPROTECTEDDOCUMENT ISO2012 All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or ISO's member body in the country of the requester. ISO copyright office Case postale 56 · CH-1211 Geneva 20 Tel. + 41 22 749 01 11 Fax + 41 22 749 09 47 E-mail copyright@iso.org Web www.iso.org Published in Switzerland @ ISO 2012 -All rights reserved No reproductic etworking permitted without license from IHS Not for Resale ISO 17497-2:2012(E) Contents Page Foreword ..iv Introduction 1 Scope 2 Normative references 3 Terms and definitions.. 4 Measurement principle 5 Frequency range. 6 Test arrangement.. 6.1 Measurementenvironment 6.2 Measurement field. 6.3 Test specimen 7 Test procedure .. 7.1 Test signals.... 7.2 Source and receiving equipment 7.3 Measurements. 7.4 Polarresponseprocessing 8 8 Expression of results .. 11 8.1 Directionaldiffusioncoefficient. 11 8.2 Normalized directional diffusion coefficient. 12 8.3 Calculation of area factors... 12 8.4 Randomincidencediffusioncoefficient 8.5 Presentation of results.. 13 9 Test report 13 Annex A (normative) Qualification of a measurement space. 14 Bibliography 15 ili license from IHS Not for Resale