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oai:www.ideals.illinois.edu:2142/95574 2023-07-11 col_2142_8888 col_2142_5131 com_2142_8887 com_2142_234 com_2142_5130

Bernhard, Jennifer T. Bernhard, Jennifer T. Franke, Steven J. Schutt-Ainé, José E. Schmitz, Christopher D. Daly, Erica Lynn 2017-03-01T17:01:19Z 2017-03-01T17:01:19Z 2019-03-02T10:15:24Z 2016-11-18 2016-12 An enabling technology for cognitive radio is expeditious wideband spectrum sensing. A major challenge for implementing wideband spectrum sensors is fitting a wideband antenna within a given form factor. Scanning a narrowband antenna is an attractive alternative to using a wideband antenna in situations where constraints on the allowable antenna dimensions make designing a sensitive wideband antenna a challenge. However, scanning the antenna through a wide spectrum extremely rapidly can induce significant nonlinear effects. This work explores the nonlinear effects of rapidly scanning a narrowband antenna in order to enable the design of devices that scan the antenna extremely rapidly. The frequency spread due to the amplitude modulation effect due to tuning and detuning the antenna is characterized. The frequency shift due to the rapidly changing phase associated with rapidly tuning an antenna is calculated. The limit on how rapidly the antenna may be tuned effectively is explored. The nonlinear effects of rapid antenna tuning are observed experimentally and replicated in simulation. Submission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2018-12-01 The student, Erica Daly, accepted the attached license on 2016-11-17 at 19:10. The student, Erica Daly, submitted this Dissertation for approval on 2016-11-17 at 19:21. This Dissertation was approved for publication on 2016-11-18 at 16:48. DSpace SAF Submission Ingestion Package generated from Vireo submission #10264 on 2017-02-28 at 14:41:36 Made available in DSpace on 2017-03-01T17:01:19Z (GMT). No. of bitstreams: 3 DALY-DISSERTATION-2016.pdf: 4822955 bytes, checksum: 44302db8a23c58d20733da6a1c25e595 (MD5) LICENSE.txt: 4207 bytes, checksum: 34c85fdcb2403c91f197563ff2f84ee2 (MD5) PROQUEST_LICENSE.txt: 4553 bytes, checksum: a78950792cb5cbe78ff526e0ea990fac (MD5) Previous issue date: 2016-11-18 Embargo set by: Seth Robbins for item 98690 Lift date: 2019-03-01T17:02:22Z Reason: Author requested closed access (OA after 2yrs) in Vireo ETD system Embargo set by: Seth Robbins for item 98690 Lift date: 2019-03-01T17:03:32Z Reason: Author requested closed access (OA after 2yrs) in Vireo ETD system Embargo set by: Seth Robbins for item 98690 Lift date: 2019-03-01T17:05:02Z Reason: Author requested closed access (OA after 2yrs) in Vireo ETD system Embargo set by: Seth Robbins for item 98690 Lift date: 2019-03-01T17:06:55Z Reason: Author requested closed access (OA after 2yrs) in Vireo ETD system Limited Restriction Lifted for Item 98690 on 2019-03-02T10:15:24Z. application/pdf http://hdl.handle.net/2142/95574 en Copyright 2016 Erica Daly Rapidly tuned antennas transient effects of antenna tuning spectrum sensing Wideband spectrum sensing using rapidly tuned antennas text text Electrical & Computer Eng Electrical & Computer Engr University of Illinois at Urbana-Champaign Dissertation Ph.D.