{"id":{"repo_id":"alabama","oai_identifier":"oai:ir.ua.edu:123456789/12780"},"canonical_url":"https://search.dev.ndltd.org/etd/alabama/oai:ir.ua.edu:123456789/12780","repository":{"repo_id":"alabama","name":"University of Alabama","base_url":"https://ir-api.ua.edu/oai/request"},"display":{"title":"Development and Optimization of Airborne FMCW Radars for High-Resolution Snow Depth Measurements","abstract":"Over one-sixth of Earth's population relies on glaciers and seasonal snowpacks for freshwater supply. In the United States, the Colorado River Basin (CRB) gets 75% of its water from snow melt; it constitutes the water supply of 40 million people in seven states, two countries, and 5.5 million irrigated acres of land. An ultra-wideband (UWB) radar enabling snowpack information production in near-real-time would greatly aid in planning and effectively distributing this precious resource.The primary objective of this research is to design, develop, and optimize UWB FMCW (Frequency-Modulated Continuous-Wave) radar systems for airborne snow measurements to generate data products in near-real-time for operational applications. We need to address a few significant engineering challenges to do this. The first is to develop a high-sensitivity FMCW radar providing near-ideal response requiring minimal signal processing for a single and multi-channel configuration. These systems must overcome sensitivity limitations posed by the internal reflections, chirp and system non-linearities, and transmitter-receiver feedthrough signals and operate in thermal noise regions, ensuring optimal performance. We can employ coherent signal processing techniques with thermal noise-limited systems and keep the transmit power low. The second is to develop a Mills-Cross antenna array for the airborne platform for these radar systems to obtain a narrow transmit-receive beamwidth. Finally, we must demonstrate that we can provide near-real-time operational data products in the field with the improved UWB radar.We performed careful design, simulations, and optimization to reduce the effects of system non-linearities, internal reflections, and chirp-related non-linearities in the radar. We extensively used modern computer-aided design (CAD) tools to optimize the transmitter and receiver sub-sections of the radar to obtain a perfect point target response that does not need additional signal processing. The radar we developed operates over 2-11 GHz and uses only 10 mW of transmit power. We addressed the challenge of obtaining the high transmitter-receiver over ultra-wide bandwidth and accommodating two large nadir-looking antennas on medium-range aircraft with a T-shape Mills-Cross antenna array with narrow two-way beamwidth. We demonstrated that we could deliver snowpack results in near real-time for operational applications within a few hours after completing each survey flight.","abstract_html":"Over one-sixth of Earth's population relies on glaciers and seasonal snowpacks for freshwater supply. In the United States, the Colorado River Basin (CRB) gets 75% of its water from snow melt; it constitutes the water supply of 40 million people in seven states, two countries, and 5.5 million irrigated acres of land. An ultra-wideband (UWB) radar enabling snowpack information production in near-real-time would greatly aid in planning and effectively distributing this precious resource.The primary objective of this research is to design, develop, and optimize UWB FMCW (Frequency-Modulated Continuous-Wave) radar systems for airborne snow measurements to generate data products in near-real-time for operational applications. We need to address a few significant engineering challenges to do this. The first is to develop a high-sensitivity FMCW radar providing near-ideal response requiring minimal signal processing for a single and multi-channel configuration. These systems must overcome sensitivity limitations posed by the internal reflections, chirp and system non-linearities, and transmitter-receiver feedthrough signals and operate in thermal noise regions, ensuring optimal performance. We can employ coherent signal processing techniques with thermal noise-limited systems and keep the transmit power low. The second is to develop a Mills-Cross antenna array for the airborne platform for these radar systems to obtain a narrow transmit-receive beamwidth. Finally, we must demonstrate that we can provide near-real-time operational data products in the field with the improved UWB radar.We performed careful design, simulations, and optimization to reduce the effects of system non-linearities, internal reflections, and chirp-related non-linearities in the radar. We extensively used modern computer-aided design (CAD) tools to optimize the transmitter and receiver sub-sections of the radar to obtain a perfect point target response that does not need additional signal processing. The radar we developed operates over 2-11 GHz and uses only 10 mW of transmit power. We addressed the challenge of obtaining the high transmitter-receiver over ultra-wide bandwidth and accommodating two large nadir-looking antennas on medium-range aircraft with a T-shape Mills-Cross antenna array with narrow two-way beamwidth. We demonstrated that we could deliver snowpack results in near real-time for operational applications within a few hours after completing each survey flight.","abstract_has_math":false,"creators":["Kolpuke, Shriniwas"],"institution":"University of Alabama Libraries","degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":["O'Neill, Charles","Larson, Jordan","Mulani, Sameer","Taylor, Drew"],"advisors":["Gogineni, S. Prasad"],"committee_chairs":[],"committee_members":[],"year":2023,"date_issued":"2023","date_published":"2023","updated_at":"2026-07-27T18:44:23Z","subjects":["Airborne FMCW Radar","Dual-polarized Ku-band radar","Mills-Cross antenna array","Multi-channel FMCW radar","Radar simulations","Soil moisture radar"],"languages":["en_US","English"],"rights":["All rights reserved by the author unless otherwise indicated."],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier.other","label":"Dc Identifier Other","values":["http://purl.lib.ua.edu/188274","u0015_0000001_0004793","Kolpuke_alatus_0004D_15349"],"render_values":[{"text":"http://purl.lib.ua.edu/188274","href":"http://purl.lib.ua.edu/188274","code":true},{"text":"u0015_0000001_0004793","href":null,"code":true},{"text":"Kolpuke_alatus_0004D_15349","href":null,"code":true}]}]},"links":{"outbound_url":"https://ir.ua.edu/handle/123456789/12780","outbound_label":"Repository record","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["O'Neill, Charles","Larson, Jordan","Mulani, Sameer","Taylor, Drew"]},{"key":"dc:contributor.advisor","label":"Advisor","values":["Gogineni, S. Prasad"]},{"key":"dc:creator","label":"Author","values":["Kolpuke, Shriniwas"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2023-11-30T15:21:27Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["9/1/2028","2023-11-30T15:21:27Z"]},{"key":"dc:date.issued","label":"Date","values":["2023"]},{"key":"dc:publisher","label":"Institution","values":["University of Alabama Libraries"]},{"key":"dc:type","label":"Dc Type","values":["thesis","text"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Airborne FMCW Radar","Dual-polarized Ku-band radar","Mills-Cross antenna array","Multi-channel FMCW radar","Radar simulations","Soil moisture radar"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["English"]},{"key":"dc:language.iso","label":"Language (ISO)","values":["en_US"]},{"key":"dc:rights","label":"Dc Rights","values":["All rights reserved by the author unless otherwise indicated."]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.other","label":"Dc Identifier Other","values":["http://purl.lib.ua.edu/188274","u0015_0000001_0004793","Kolpuke_alatus_0004D_15349"]},{"key":"dc:identifier.uri","label":"Identifier URI","values":["https://ir.ua.edu/handle/123456789/12780"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Electronic Thesis or Dissertation"]},{"key":"dc:description.abstract","label":"Abstract","values":["Over one-sixth of Earth's population relies on glaciers and seasonal snowpacks for freshwater supply. In the United States, the Colorado River Basin (CRB) gets 75% of its water from snow melt; it constitutes the water supply of 40 million people in seven states, two countries, and 5.5 million irrigated acres of land. An ultra-wideband (UWB) radar enabling snowpack information production in near-real-time would greatly aid in planning and effectively distributing this precious resource.The primary objective of this research is to design, develop, and optimize UWB FMCW (Frequency-Modulated Continuous-Wave) radar systems for airborne snow measurements to generate data products in near-real-time for operational applications. We need to address a few significant engineering challenges to do this. The first is to develop a high-sensitivity FMCW radar providing near-ideal response requiring minimal signal processing for a single and multi-channel configuration. These systems must overcome sensitivity limitations posed by the internal reflections, chirp and system non-linearities, and transmitter-receiver feedthrough signals and operate in thermal noise regions, ensuring optimal performance. We can employ coherent signal processing techniques with thermal noise-limited systems and keep the transmit power low. The second is to develop a Mills-Cross antenna array for the airborne platform for these radar systems to obtain a narrow transmit-receive beamwidth. Finally, we must demonstrate that we can provide near-real-time operational data products in the field with the improved UWB radar.We performed careful design, simulations, and optimization to reduce the effects of system non-linearities, internal reflections, and chirp-related non-linearities in the radar. We extensively used modern computer-aided design (CAD) tools to optimize the transmitter and receiver sub-sections of the radar to obtain a perfect point target response that does not need additional signal processing. The radar we developed operates over 2-11 GHz and uses only 10 mW of transmit power. We addressed the challenge of obtaining the high transmitter-receiver over ultra-wide bandwidth and accommodating two large nadir-looking antennas on medium-range aircraft with a T-shape Mills-Cross antenna array with narrow two-way beamwidth. We demonstrated that we could deliver snowpack results in near real-time for operational applications within a few hours after completing each survey flight."]},{"key":"dc:format.medium","label":"Dc Format Medium","values":["electronic"]},{"key":"dc:format.mimetype","label":"Dc Format Mimetype","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["Development and Optimization of Airborne FMCW Radars for High-Resolution Snow Depth Measurements"]}]}],"canonical_facts":{"dc:contributor":["O'Neill, Charles","Larson, Jordan","Mulani, Sameer","Taylor, Drew"],"dc:contributor.advisor":["Gogineni, S. Prasad"],"dc:creator":["Kolpuke, Shriniwas"],"dc:date.accessioned":["2023-11-30T15:21:27Z"],"dc:date.available":["9/1/2028","2023-11-30T15:21:27Z"],"dc:date.issued":["2023"],"dc:description":["Electronic Thesis or Dissertation"],"dc:description.abstract":["Over one-sixth of Earth's population relies on glaciers and seasonal snowpacks for freshwater supply. In the United States, the Colorado River Basin (CRB) gets 75% of its water from snow melt; it constitutes the water supply of 40 million people in seven states, two countries, and 5.5 million irrigated acres of land. An ultra-wideband (UWB) radar enabling snowpack information production in near-real-time would greatly aid in planning and effectively distributing this precious resource.The primary objective of this research is to design, develop, and optimize UWB FMCW (Frequency-Modulated Continuous-Wave) radar systems for airborne snow measurements to generate data products in near-real-time for operational applications. We need to address a few significant engineering challenges to do this. The first is to develop a high-sensitivity FMCW radar providing near-ideal response requiring minimal signal processing for a single and multi-channel configuration. These systems must overcome sensitivity limitations posed by the internal reflections, chirp and system non-linearities, and transmitter-receiver feedthrough signals and operate in thermal noise regions, ensuring optimal performance. We can employ coherent signal processing techniques with thermal noise-limited systems and keep the transmit power low. The second is to develop a Mills-Cross antenna array for the airborne platform for these radar systems to obtain a narrow transmit-receive beamwidth. Finally, we must demonstrate that we can provide near-real-time operational data products in the field with the improved UWB radar.We performed careful design, simulations, and optimization to reduce the effects of system non-linearities, internal reflections, and chirp-related non-linearities in the radar. We extensively used modern computer-aided design (CAD) tools to optimize the transmitter and receiver sub-sections of the radar to obtain a perfect point target response that does not need additional signal processing. The radar we developed operates over 2-11 GHz and uses only 10 mW of transmit power. We addressed the challenge of obtaining the high transmitter-receiver over ultra-wide bandwidth and accommodating two large nadir-looking antennas on medium-range aircraft with a T-shape Mills-Cross antenna array with narrow two-way beamwidth. We demonstrated that we could deliver snowpack results in near real-time for operational applications within a few hours after completing each survey flight."],"dc:format.medium":["electronic"],"dc:format.mimetype":["application/pdf"],"dc:identifier.other":["http://purl.lib.ua.edu/188274","u0015_0000001_0004793","Kolpuke_alatus_0004D_15349"],"dc:identifier.uri":["https://ir.ua.edu/handle/123456789/12780"],"dc:language":["English"],"dc:language.iso":["en_US"],"dc:publisher":["University of Alabama Libraries"],"dc:rights":["All rights reserved by the author unless otherwise indicated."],"dc:subject":["Airborne FMCW Radar","Dual-polarized Ku-band radar","Mills-Cross antenna array","Multi-channel FMCW radar","Radar simulations","Soil moisture radar"],"dc:title":["Development and Optimization of Airborne FMCW Radars for High-Resolution Snow Depth Measurements"],"dc:type":["thesis","text"]},"updated_at":"2026-07-27T18:44:23Z"}