Show simple item record

Files in this item


Item metadata

dc.contributor.authorMacfarlane, David Graham
dc.contributor.authorRobertson, Duncan A.
dc.contributor.authorCapponi, Antonio
dc.contributor.editorRanney, Kenneth
dc.contributor.editorRaynal, Ann
dc.identifier.citationMacfarlane , D G , Robertson , D A & Capponi , A 2021 , R4AsH : a triple frequency laboratory radar for characterizing falling volcanic ash . in K Ranney & A Raynal (eds) , Radar Sensor Technology XXV . Proceedings of SPIE , vol. 11742 , SPIE , SPIE Defense + Commercial Sensing , 12/04/21 .
dc.identifier.otherPURE: 273887378
dc.identifier.otherPURE UUID: 99b965b3-5d82-4329-8922-64eb65846524
dc.identifier.otherORCID: /0000-0002-4042-2772/work/92775857
dc.identifier.otherScopus: 85107417448
dc.identifier.otherWOS: 000691546200025
dc.description.abstractAirborne ash generated by explosive volcanic eruptions presents a significant danger to aviation. Accurate modelling and predictions of the dispersal of hazardous ash into the atmosphere are currently hampered by uncertainties in the ‘source term’ parameters associated with the initial eruption plume, specifically the amount and size of ash particles released into the atmosphere. Ground based radar offers the means to remotely measure ash reflectivity, however estimation of source term parameters from reflectivity measured by single frequency radar is limited by ambiguity between the contribution of particle size distribution (PSD) and ash concentration in the plume. This means that one of these parameters must be assumed rather than measured directly, leading to uncertainties in forecasting eruption hazards. We report on R4AsH, a close range FMCW radar designed to resolve this ambiguity by simultaneous characterization of falling volcanic ash in a laboratory-controlled environment at three different frequencies: 10, 35 and 94 GHz. The R4AsH design uses a single DDS based chirp generator as a common source, multiplied and upconverted to feed three sets of transmit-receive horn antennas directed at a common target volume such that measurements will give spatially and temporally coincident measurements of falling ash. In addition, there will be independent measurement of the PSD using optical imaging and logging of the landing particle mass to calibrate results and inform analysis. The aim of R4AsH is to develop a triplefrequency inversion algorithm to enable simultaneous retrieval of PSD and ash concentration from radar data suitable for future volcano monitoring systems.
dc.relation.ispartofRadar Sensor Technology XXVen
dc.relation.ispartofseriesProceedings of SPIEen
dc.rightsCopyright © 2021 SPIE. This work has been made available online in accordance with publisher policies or with permission. Permission for further reuse of this content should be sought from the publisher or the rights holder. This is the final published version of the work, which was originally published at
dc.subjectVolcanic ashen
dc.subjectFMCW radaren
dc.subjectRadar cross sectionen
dc.subjectHorn antennaen
dc.subjectQC Physicsen
dc.subjectT Technologyen
dc.titleR4AsH : a triple frequency laboratory radar for characterizing falling volcanic ashen
dc.typeConference itemen
dc.description.versionPublisher PDFen
dc.contributor.institutionUniversity of St Andrews. School of Physics and Astronomyen

This item appears in the following Collection(s)

Show simple item record