2026-09-21T16:16:21Z https://www.ideals.illinois.edu/oai-pmh

oai:www.ideals.illinois.edu:2142/42321 2023-07-11 col_2142_8888 col_2142_5131 com_2142_8887 com_2142_234 com_2142_5130

Bernhard, Jennifer T. Bernhard, Jennifer T. Cangellaris, Andreas C. Jones, Douglas L. Franke, Steven J. Daly, Michael 2013-02-03T19:35:18Z 2013-02-03T19:35:18Z 2012-12 2013-02-03T19:35:18Z 2012-12 Traditionally, antenna systems have been designed to achieve reliable wireless communication, while the problem of securing that communication from eavesdropping was left to mathematical cryptography. Recent research into physical layer encryption shows that jointly designing for reliability and secrecy at the physical layer may be a better solution. Physical layer encryption involves techniques that ensure a signal is information-theoretically secure, meaning that an eavesdropper with infinite time and computational resources will not be able to decode a message. Such techniques include purposely broadcasting artificial noise, transmitting direction-dependent signals, and opportunistic communications. This work addresses different methods for broadcasting artificial noise using fixed arrays, including tradeoffs with power usage and computational complexity. In addition, a method of producing direction-dependent distortion using reconfigurable arrays is also shown. These two methods are combined and shown to be more secure and power-efficient than either in isolation. An analysis of secrecy rates through mutual information makes it possible to compare the performance of all the various secure communication techniques. Simulations with various wireless channels as well as an experimental test using a fixed and reconfigurable array are presented. Item withdrawn by Mark Zulauf (zulauf@illinois.edu) on 2012-10-24T16:20:45Z Item was in collections: University of Illinois Theses & Dissertations (ID: 1) No. of bitstreams: 1 Daly_Michael.pdf: 3149696 bytes, checksum: 8624ef88bf4e2802831f515a41c5cf8c (MD5) Made available in DSpace on 2013-02-03T19:35:18Z (GMT). No. of bitstreams: 2 Michael_Daly.pdf: 3149696 bytes, checksum: 8624ef88bf4e2802831f515a41c5cf8c (MD5) license.txt: 4060 bytes, checksum: 8641f188bee39c250c3d9231ff7c9d02 (MD5) http://hdl.handle.net/2142/42321 en Copyright 2012 Michael P. Daly physical layer encryption artificial noise reconfigurable antennas secrecy capacity Physical layer encryption using fixed and reconfigurable antennas text Electrical & Computer Eng 1933 Electrical & Computer Engr 1200 University of Illinois at Urbana-Champaign Dissertation Ph.D. PHD:Electr & Computer Eng-UIUC 10KS1200PHD