Cognitive Wireless Networks Cognitive Wireless Networks Concepts, Methodologies and Visions Inspiring the Age of Enlightenment of Wireless Communications
Cognitive Wireless Networks Cognitive Wireless Networks Concepts, Methodologies and Visions Inspiring the Age of Enlightenment of Wireless Communications Edited by Frank H.P. Fitzek Aalborg University, Denmark and Marcos D. Katz VTT, Finland A C.I.P. Catalogue record for this book is available from the Library of Congress. ISBN 978-1-4020-5978-0 (HB) ISBN 978-1-4020-5979-7 (e-book) Published by Springer, P.O. Box 17, 3300 AA Dordrecht, The Netherlands. www.springer.com Printed on acid-free paper © 2007 Springer No part of this work may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, microfilming, recording or otherwise, without written permission from the Publisher, with the exception of any material supplied specifically for the purpose of being entered and executed on a computer system, for exclusive use by the purchaser of the work. To our parents Eta-Marie and Werner Fanny and Abraham (in memoriam) for their eternal support and loving. What is Cognitive Radio and Cognitive Networks? Bernhard Walke RWTH Aachen University, Aachen, Germany Cognitive Networks based on cognitive radio are addressing a revolutionary technology aiming, besides others, at remarkably improving efficiency of spec- trum usage. When introduced, it will fundamentally change the way radio spectrum is regulated and used. Before this may happen, new enabling prop- erties of radios are required such as sensing spectrum occupancy covering a wide range of spectrum and flexible spectrum access adapting to variable channel widths based on reasoning. Cognition has much to do with coex- istence management: Coexistence of radio based systems operating in the same or in partly overlapping channels using the same or even different air- interfaces is the challenge to be solved.
[Show full text]