{"id":{"repo_id":"edithcowan","oai_identifier":"oai:ro.ecu.edu.au:theses-1876"},"canonical_url":"https://search.dev.ndltd.org/etd/edithcowan/oai:ro.ecu.edu.au:theses-1876","repository":{"repo_id":"edithcowan","name":"Edith Cowan University","base_url":"https://ro.ecu.edu.au/do/oai/"},"display":{"title":"Magnetocardiography in unshielded environment based on optical magnetometry and adaptive noise cancellation","abstract":"This thesis proposes and demonstrates the concept of a magnetocardiographic system employing an array of optically-pumped quantum magnetometers and an adaptive noise cancellation for heart magnetic field measurement within a magnetically-unshielded environment. Optically-pumped quantum magnetometers are based on the use of the atomic-spin-dependent optical properties of an atomic medium. An Mxconfiguration- based optically-pumped quantum magnetometer employing two sensing cells containing caesium vapour is theoretically described and experimentally developed, and the dependence of its sensitivity and frequency bandwidth upon the light power and the alkali vapour temperature is experimentally demonstrated. Furthermore, the capability of the developed magnetometer of measuring very weak magnetic fields is experimentally demonstrated in a magnetically-unshielded environment. The adaptive noise canceller is based on standard Least-Mean-Squares (LMS) algorithms and on two heuristic optimization techniques, namely, Genetic Algorithms (GA) and Particle Swarm Optimization (PSO). The use of these algorithms is investigated for suppressing the power line generated 50Hz interference and recovering of the weak magnetic heart signals from a much higher electromagnetic environmental noise. Experimental results show that all the algorithms can extract a weak heart signal from a much-stronger magnetic noise, detect the P, QRS, and T heart features and highly suppress the common power line noise component at 50 Hz. Moreover, adaptive noise cancellation based on heuristic algorithms is shown to be more efficient than adaptive noise canceller based on standard or normalised LMS algorithm in heart features detection.","abstract_html":"This thesis proposes and demonstrates the concept of a magnetocardiographic system employing an array of optically-pumped quantum magnetometers and an adaptive noise cancellation for heart magnetic field measurement within a magnetically-unshielded environment. Optically-pumped quantum magnetometers are based on the use of the atomic-spin-dependent optical properties of an atomic medium. An Mxconfiguration- based optically-pumped quantum magnetometer employing two sensing cells containing caesium vapour is theoretically described and experimentally developed, and the dependence of its sensitivity and frequency bandwidth upon the light power and the alkali vapour temperature is experimentally demonstrated. Furthermore, the capability of the developed magnetometer of measuring very weak magnetic fields is experimentally demonstrated in a magnetically-unshielded environment. The adaptive noise canceller is based on standard Least-Mean-Squares (LMS) algorithms and on two heuristic optimization techniques, namely, Genetic Algorithms (GA) and Particle Swarm Optimization (PSO). The use of these algorithms is investigated for suppressing the power line generated 50Hz interference and recovering of the weak magnetic heart signals from a much higher electromagnetic environmental noise. Experimental results show that all the algorithms can extract a weak heart signal from a much-stronger magnetic noise, detect the P, QRS, and T heart features and highly suppress the common power line noise component at 50 Hz. Moreover, adaptive noise cancellation based on heuristic algorithms is shown to be more efficient than adaptive noise canceller based on standard or normalised LMS algorithm in heart features detection.","abstract_has_math":false,"creators":["Tiporlini, Valentina"],"institution":"Edith Cowan University, Research Online, Perth, Western Australia","degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2013,"date_issued":"2013-01-01T08:00:00Z","date_published":"2013-01-01T08:00:00Z","updated_at":"2026-07-27T19:21:40Z","subjects":["Magnetooptical devices","Heart rate monitoring","Electrocardiography","Magnetocardiography","Optical magnetometry","Adaptive Noise Cancellation","Least Mean Squares Algorithm","Genetic Algorithms","Particle Swarm Optimization","Analytical, Diagnostic and Therapeutic Techniques and Equipment"],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://ro.ecu.edu.au/theses/875","outbound_label":"Repository record","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:creator","label":"Author","values":["Tiporlini, Valentina"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2013-01-01T08:00:00Z"]},{"key":"dc:publisher","label":"Institution","values":["Edith Cowan University, Research Online, Perth, Western Australia"]},{"key":"dc:type","label":"Dc Type","values":["thesis"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Magnetooptical devices","Heart rate monitoring","Electrocardiography","Magnetocardiography","Optical magnetometry","Adaptive Noise Cancellation","Least Mean Squares Algorithm","Genetic Algorithms","Particle Swarm Optimization","Analytical, Diagnostic and Therapeutic Techniques and Equipment"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://ro.ecu.edu.au/theses/875","https://ro.ecu.edu.au/context/theses/article/1876/viewcontent/Magnetocardiography_in_unshielded_environment_based_on_optical_magnetometry_Redacted.pdf"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["This thesis proposes and demonstrates the concept of a magnetocardiographic system employing an array of optically-pumped quantum magnetometers and an adaptive noise cancellation for heart magnetic field measurement within a magnetically-unshielded environment. Optically-pumped quantum magnetometers are based on the use of the atomic-spin-dependent optical properties of an atomic medium. An Mxconfiguration- based optically-pumped quantum magnetometer employing two sensing cells containing caesium vapour is theoretically described and experimentally developed, and the dependence of its sensitivity and frequency bandwidth upon the light power and the alkali vapour temperature is experimentally demonstrated. Furthermore, the capability of the developed magnetometer of measuring very weak magnetic fields is experimentally demonstrated in a magnetically-unshielded environment. The adaptive noise canceller is based on standard Least-Mean-Squares (LMS) algorithms and on two heuristic optimization techniques, namely, Genetic Algorithms (GA) and Particle Swarm Optimization (PSO). The use of these algorithms is investigated for suppressing the power line generated 50Hz interference and recovering of the weak magnetic heart signals from a much higher electromagnetic environmental noise. Experimental results show that all the algorithms can extract a weak heart signal from a much-stronger magnetic noise, detect the P, QRS, and T heart features and highly suppress the common power line noise component at 50 Hz. Moreover, adaptive noise cancellation based on heuristic algorithms is shown to be more efficient than adaptive noise canceller based on standard or normalised LMS algorithm in heart features detection."]},{"key":"dc:format","label":"Dc Format","values":["application/pdf"]},{"key":"dc:source","label":"Dc Source","values":["Theses: Doctorates and Masters"]},{"key":"dc:title","label":"Title","values":["Magnetocardiography in unshielded environment based on optical magnetometry and adaptive noise cancellation"]}]}],"canonical_facts":{"dc:creator":["Tiporlini, Valentina"],"dc:date":["2013-01-01T08:00:00Z"],"dc:description":["This thesis proposes and demonstrates the concept of a magnetocardiographic system employing an array of optically-pumped quantum magnetometers and an adaptive noise cancellation for heart magnetic field measurement within a magnetically-unshielded environment. Optically-pumped quantum magnetometers are based on the use of the atomic-spin-dependent optical properties of an atomic medium. An Mxconfiguration- based optically-pumped quantum magnetometer employing two sensing cells containing caesium vapour is theoretically described and experimentally developed, and the dependence of its sensitivity and frequency bandwidth upon the light power and the alkali vapour temperature is experimentally demonstrated. Furthermore, the capability of the developed magnetometer of measuring very weak magnetic fields is experimentally demonstrated in a magnetically-unshielded environment. The adaptive noise canceller is based on standard Least-Mean-Squares (LMS) algorithms and on two heuristic optimization techniques, namely, Genetic Algorithms (GA) and Particle Swarm Optimization (PSO). The use of these algorithms is investigated for suppressing the power line generated 50Hz interference and recovering of the weak magnetic heart signals from a much higher electromagnetic environmental noise. Experimental results show that all the algorithms can extract a weak heart signal from a much-stronger magnetic noise, detect the P, QRS, and T heart features and highly suppress the common power line noise component at 50 Hz. Moreover, adaptive noise cancellation based on heuristic algorithms is shown to be more efficient than adaptive noise canceller based on standard or normalised LMS algorithm in heart features detection."],"dc:format":["application/pdf"],"dc:identifier":["https://ro.ecu.edu.au/theses/875","https://ro.ecu.edu.au/context/theses/article/1876/viewcontent/Magnetocardiography_in_unshielded_environment_based_on_optical_magnetometry_Redacted.pdf"],"dc:publisher":["Edith Cowan University, Research Online, Perth, Western Australia"],"dc:source":["Theses: Doctorates and Masters"],"dc:subject":["Magnetooptical devices","Heart rate monitoring","Electrocardiography","Magnetocardiography","Optical magnetometry","Adaptive Noise Cancellation","Least Mean Squares Algorithm","Genetic Algorithms","Particle Swarm Optimization","Analytical, Diagnostic and Therapeutic Techniques and Equipment"],"dc:title":["Magnetocardiography in unshielded environment based on optical magnetometry and adaptive noise cancellation"],"dc:type":["thesis"]},"updated_at":"2026-07-27T19:21:40Z"}