{"id":{"repo_id":"vt","oai_identifier":"oai:vtechworks.lib.vt.edu:10919/34392"},"canonical_url":"https://search.dev.ndltd.org/etd/vt/oai:vtechworks.lib.vt.edu:10919/34392","repository":{"repo_id":"vt","name":"Virginia Tech","base_url":"https://vtechworks.lib.vt.edu/oai/request"},"display":{"title":"Log-Periodic Loop Antennas","abstract":"The Log-Periodic Loop Antenna with Ground Reflector (LPLA-GR) is investigated as a new type of antenna, which provides wide bandwidth, broad beamwidth, and high gain. This antenna has smaller transverse dimensions (by a factor of 2/pi) than a log-periodic dipole antenna with comparable radiation characteristics. Several geometries with different parameters are analyzed numerically using ESP code, which is based on the method of moments. A LPLA-GR with 6 turns and a cone angle of 30* offers the most promising radiation characteristics. This antenna yields 47.6 % gain bandwidth and 12 dB gain according to the numerical analysis. The LPLA-GR also provides linear polarization and unidirectional patterns. Three prototype antennas were constructed and measured in the Virginia Tech Antenna Laboratory. Far-field patterns and input impedance were measured over a wide range of frequencies. The measured results agree well with the calculated results. Because of its wide bandwidth, high gain, and small size, the LPLA is expected to find applications as feeds for reflector antennas, as detectors in EMC scattering range, and as mobile communication antennas.","abstract_html":"The Log-Periodic Loop Antenna with Ground Reflector (LPLA-GR) is investigated as a new type of antenna, which provides wide bandwidth, broad beamwidth, and high gain. This antenna has smaller transverse dimensions (by a factor of 2/pi) than a log-periodic dipole antenna with comparable radiation characteristics. Several geometries with different parameters are analyzed numerically using ESP code, which is based on the method of moments. A LPLA-GR with 6 turns and a cone angle of 30* offers the most promising radiation characteristics. This antenna yields 47.6 % gain bandwidth and 12 dB gain according to the numerical analysis. The LPLA-GR also provides linear polarization and unidirectional patterns. Three prototype antennas were constructed and measured in the Virginia Tech Antenna Laboratory. Far-field patterns and input impedance were measured over a wide range of frequencies. The measured results agree well with the calculated results. Because of its wide bandwidth, high gain, and small size, the LPLA is expected to find applications as feeds for reflector antennas, as detectors in EMC scattering range, and as mobile communication antennas.","abstract_has_math":false,"creators":["Kim, Jeong I."],"institution":"Virginia Tech","degree_name":"Master of Science","degree_level":"masters","degree_discipline":"Electrical and Computer Engineering","degree_department":"Electrical and Computer Engineering","school":null,"contributors":[],"advisors":[],"committee_chairs":["Safaai-Jazi, Ahmad"],"committee_members":["Stutzman, Warren L.","Poon, Ting-Chung"],"year":1999,"date_issued":"1999-07-27","date_published":"1999-07-27","updated_at":"2026-07-22T22:19:49Z","subjects":["Log-Periodic Loop Antenna","Log-Periodic Dipole Antenna","Ground Reflector","ESP","Frequency Independent Antenna"],"languages":[],"rights":["In Copyright"],"rights_urls":["http://rightsstatements.org/vocab/InC/1.0/"],"identifier_entries":[{"key":"dc:identifier.other","label":"Dc Identifier Other","values":["etd-080699-180221"],"render_values":[{"text":"etd-080699-180221","href":null,"code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/10919/34392","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.committeechair","label":"Committee Chair","values":["Safaai-Jazi, Ahmad"]},{"key":"dc:contributor.committeemember","label":"Committee Member","values":["Stutzman, Warren L.","Poon, Ting-Chung"]},{"key":"dc:contributor.department","label":"Department","values":["Electrical and Computer Engineering"]},{"key":"dc:creator","label":"Author","values":["Kim, Jeong I."]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2014-03-14T20:42:53Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2014-03-14T20:42:53Z","2000-08-13"]},{"key":"dc:date.issued","label":"Date","values":["1999-07-27"]},{"key":"dc:publisher","label":"Institution","values":["Virginia Tech"]},{"key":"dc:type","label":"Dc Type","values":["Thesis"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Electrical and Computer Engineering"]},{"key":"thesis:degree_level","label":"Degree Level","values":["masters"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Master of Science"]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["Virginia Polytechnic Institute and State University"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Log-Periodic Loop Antenna","Log-Periodic Dipole Antenna","Ground Reflector","ESP","Frequency Independent Antenna"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:rights","label":"Dc Rights","values":["In Copyright"]},{"key":"dc:rights.uri","label":"Rights URI","values":["http://rightsstatements.org/vocab/InC/1.0/"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.other","label":"Dc Identifier Other","values":["etd-080699-180221"]},{"key":"dc:identifier.uri","label":"Identifier URI","values":["http://hdl.handle.net/10919/34392"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["The Log-Periodic Loop Antenna with Ground Reflector (LPLA-GR) is investigated as a new type of antenna, which provides wide bandwidth, broad beamwidth, and high gain. This antenna has smaller transverse dimensions (by a factor of 2/pi) than a log-periodic dipole antenna with comparable radiation characteristics. Several geometries with different parameters are analyzed numerically using ESP code, which is based on the method of moments. A LPLA-GR with 6 turns and a cone angle of 30* offers the most promising radiation characteristics. This antenna yields 47.6 % gain bandwidth and 12 dB gain according to the numerical analysis. The LPLA-GR also provides linear polarization and unidirectional patterns. Three prototype antennas were constructed and measured in the Virginia Tech Antenna Laboratory. Far-field patterns and input impedance were measured over a wide range of frequencies. The measured results agree well with the calculated results. Because of its wide bandwidth, high gain, and small size, the LPLA is expected to find applications as feeds for reflector antennas, as detectors in EMC scattering range, and as mobile communication antennas."]},{"key":"dc:description.degree","label":"Dc Description Degree","values":["Master of Science"]},{"key":"dc:title","label":"Title","values":["Log-Periodic Loop Antennas"]}]}],"canonical_facts":{"dc:contributor.committeechair":["Safaai-Jazi, Ahmad"],"dc:contributor.committeemember":["Stutzman, Warren L.","Poon, Ting-Chung"],"dc:contributor.department":["Electrical and Computer Engineering"],"dc:creator":["Kim, Jeong I."],"dc:date.accessioned":["2014-03-14T20:42:53Z"],"dc:date.available":["2014-03-14T20:42:53Z","2000-08-13"],"dc:date.issued":["1999-07-27"],"dc:description.abstract":["The Log-Periodic Loop Antenna with Ground Reflector (LPLA-GR) is investigated as a new type of antenna, which provides wide bandwidth, broad beamwidth, and high gain. This antenna has smaller transverse dimensions (by a factor of 2/pi) than a log-periodic dipole antenna with comparable radiation characteristics. Several geometries with different parameters are analyzed numerically using ESP code, which is based on the method of moments. A LPLA-GR with 6 turns and a cone angle of 30* offers the most promising radiation characteristics. This antenna yields 47.6 % gain bandwidth and 12 dB gain according to the numerical analysis. The LPLA-GR also provides linear polarization and unidirectional patterns. Three prototype antennas were constructed and measured in the Virginia Tech Antenna Laboratory. Far-field patterns and input impedance were measured over a wide range of frequencies. The measured results agree well with the calculated results. Because of its wide bandwidth, high gain, and small size, the LPLA is expected to find applications as feeds for reflector antennas, as detectors in EMC scattering range, and as mobile communication antennas."],"dc:description.degree":["Master of Science"],"dc:identifier.other":["etd-080699-180221"],"dc:identifier.uri":["http://hdl.handle.net/10919/34392"],"dc:publisher":["Virginia Tech"],"dc:rights":["In Copyright"],"dc:rights.uri":["http://rightsstatements.org/vocab/InC/1.0/"],"dc:subject":["Log-Periodic Loop Antenna","Log-Periodic Dipole Antenna","Ground Reflector","ESP","Frequency Independent Antenna"],"dc:title":["Log-Periodic Loop Antennas"],"dc:type":["Thesis"],"thesis:degree_discipline":["Electrical and Computer Engineering"],"thesis:degree_level":["masters"],"thesis:degree_name":["Master of Science"],"thesis:institution_name":["Virginia Polytechnic Institute and State University"]},"updated_at":"2026-07-22T22:19:49Z"}