{"id":{"repo_id":"mit","oai_identifier":"oai:dspace.mit.edu:1721.1/16945"},"canonical_url":"https://search.dev.ndltd.org/etd/mit/oai:dspace.mit.edu:1721.1/16945","repository":{"repo_id":"mit","name":"MIT","base_url":"https://dspace.mit.edu/oai/request"},"display":{"title":"Structure of the polar electrojet antenna","abstract":"Field experiments were performed in Gakona, Alaska in August and November 2002. The ionospheric conductivity was periodically perturbed using amplitude-modulated radiation from the HAARP HF transmitter (1 MW power, 14 dB gain, 3.3-5.8 MHz carrier, 0.1-40 kHz modulation). The conductivity perturbations lead to perturbations to the natural flow of electrojet current in the lower ionosphere, resulting in ELF/VLF radiation at the modulation frequency. Measurements of the radiation, along with analytic and numerical models, suggest that a vertical loop with a scale size of 10 km is the dominant current structure excited during the experiments.","abstract_html":"Field experiments were performed in Gakona, Alaska in August and November 2002. The ionospheric conductivity was periodically perturbed using amplitude-modulated radiation from the HAARP HF transmitter (1 MW power, 14 dB gain, 3.3-5.8 MHz carrier, 0.1-40 kHz modulation). The conductivity perturbations lead to perturbations to the natural flow of electrojet current in the lower ionosphere, resulting in ELF/VLF radiation at the modulation frequency. Measurements of the radiation, along with analytic and numerical models, suggest that a vertical loop with a scale size of 10 km is the dominant current structure excited during the experiments.","abstract_has_math":false,"creators":["Riddolls, Ryan James, 1974-"],"institution":"Massachusetts Institute of Technology","degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":"Massachusetts Institute of Technology. Dept. of Electrical Engineering and Computer Science.","school":null,"contributors":[],"advisors":["Min-Chang Lee."],"committee_chairs":[],"committee_members":[],"year":2003,"date_issued":"2003","date_published":"2003","updated_at":"2026-07-22T22:21:52Z","subjects":["Electrical Engineering and Computer Science."],"languages":["eng"],"rights":["M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission."],"rights_urls":["http://dspace.mit.edu/handle/1721.1/7582"],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/1721.1/16945","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["Min-Chang Lee."]},{"key":"dc:contributor.department","label":"Department","values":["Massachusetts Institute of Technology. Dept. of Electrical Engineering and Computer Science."]},{"key":"dc:contributor.other","label":"Dc Contributor Other","values":["Massachusetts Institute of Technology. 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They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission."]},{"key":"dc:rights.uri","label":"Rights URI","values":["http://dspace.mit.edu/handle/1721.1/7582"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["http://hdl.handle.net/1721.1/16945"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2003.","Includes bibliographical references (p. 153-156).","This electronic version was submitted by the student author. 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Measurements of the radiation, along with analytic and numerical models, suggest that a vertical loop with a scale size of 10 km is the dominant current structure excited during the experiments."]},{"key":"dc:description.degree","label":"Dc Description Degree","values":["Ph.D."]},{"key":"dc:format.mimetype","label":"Dc Format Mimetype","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["Structure of the polar electrojet antenna"]}]}],"canonical_facts":{"dc:contributor.advisor":["Min-Chang Lee."],"dc:contributor.department":["Massachusetts Institute of Technology. Dept. of Electrical Engineering and Computer Science."],"dc:contributor.other":["Massachusetts Institute of Technology. Dept. of Electrical Engineering and Computer Science."],"dc:creator":["Riddolls, Ryan James, 1974-"],"dc:date.accessioned":["2005-05-19T15:23:18Z"],"dc:date.available":["2005-05-19T15:23:18Z"],"dc:date.issued":["2003"],"dc:description":["Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2003.","Includes bibliographical references (p. 153-156).","This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections."],"dc:description.abstract":["Field experiments were performed in Gakona, Alaska in August and November 2002. The ionospheric conductivity was periodically perturbed using amplitude-modulated radiation from the HAARP HF transmitter (1 MW power, 14 dB gain, 3.3-5.8 MHz carrier, 0.1-40 kHz modulation). The conductivity perturbations lead to perturbations to the natural flow of electrojet current in the lower ionosphere, resulting in ELF/VLF radiation at the modulation frequency. Measurements of the radiation, along with analytic and numerical models, suggest that a vertical loop with a scale size of 10 km is the dominant current structure excited during the experiments."],"dc:description.degree":["Ph.D."],"dc:format.mimetype":["application/pdf"],"dc:identifier.uri":["http://hdl.handle.net/1721.1/16945"],"dc:language.iso":["eng"],"dc:publisher":["Massachusetts Institute of Technology"],"dc:rights":["M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission."],"dc:rights.uri":["http://dspace.mit.edu/handle/1721.1/7582"],"dc:subject":["Electrical Engineering and Computer Science."],"dc:title":["Structure of the polar electrojet antenna"],"dc:type":["Thesis"]},"updated_at":"2026-07-22T22:21:52Z"}