{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T02:55:49Z","timestamp":1760151349548,"version":"build-2065373602"},"reference-count":65,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2022,2,24]],"date-time":"2022-02-24T00:00:00Z","timestamp":1645660800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>A method that formulates the retrieval of drop size distribution (DSD) parameters from polarimetric radar variables at attenuating frequency as the solution of an inverse problem is presented. The DSD in each radar bin is represented by a normalized Gamma distribution defined by three parameters (Dm,N0*,\u03bc). The direct problem that describes polarimetric radar observables\u2014scattering and propagation terms\u2014and their dependency on DSD parameters is analyzed based on T-matrix scattering simulations. The inverse algorithm and its application to the DSD retrieval are then presented. The inverse method is applied to an African Monsoon Multidisciplinary Analysis (AMMA) field campaign that deployed an X-band dual-polarization Doppler radar and optical disdrometers in Benin, West Africa, in 2006 and 2007. The dataset is composed of X-band polarimetric radar PPIs and disdrometer data for 15 organized convective systems observed in 2006. A priori information on DSD parameters (benchmark method) is derived from the polarimetric radar observables by applying power law relationships. The proposed retrieval method of DSD parameters leads to the following results as compared to the benchmark: (i) we found a better spatial consistency of the retrieved parameters, (ii) the reconstructed polarimetric radar observables are closer to the observations, (iii) The validation with disdrometer data confirms an improved estimation of the DSD parameters.<\/jats:p>","DOI":"10.3390\/rs14051116","type":"journal-article","created":{"date-parts":[[2022,2,24]],"date-time":"2022-02-24T21:11:07Z","timestamp":1645737067000},"page":"1116","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["An Inverse Method for Drop Size Distribution Retrieval from Polarimetric Radar at Attenuating Frequency"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4874-9008","authenticated-orcid":false,"given":"Matias","family":"Alcoba","sequence":"first","affiliation":[{"name":"G\u00e9oscience Environnement Toulouse, GET (CNRS-IRD-Universit\u00e9 de Toulouse III-CNES), 31500 Toulouse, France"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0997-8537","authenticated-orcid":false,"given":"Herv\u00e9","family":"Andrieu","sequence":"additional","affiliation":[{"name":"G\u00e9otechnique, Environnement, Risques Naturels et Sciences de la Terre, GERS-LEE, IFSTTAR, Universite Gustave Eiffel, 44344 Bouguenais, France"}]},{"given":"Marielle","family":"Gosset","sequence":"additional","affiliation":[{"name":"G\u00e9oscience Environnement Toulouse, GET (CNRS-IRD-Universit\u00e9 de Toulouse III-CNES), 31500 Toulouse, France"}]}],"member":"1968","published-online":{"date-parts":[[2022,2,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"6155","DOI":"10.1029\/1998JD200098","article-title":"Systematic Variation of Drop Size and Radar-Rainfall Relations","volume":"104","author":"Atlas","year":"1999","journal-title":"J. Geophys. Res. Atmos."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"241","DOI":"10.1175\/JAM2183.1","article-title":"Variability of Drop Size Distributions: Time-Scale Dependence of the Variability and Its Effects on Rain Estimation","volume":"44","author":"Lee","year":"2005","journal-title":"J. Appl. Meteorol."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"264","DOI":"10.1175\/1520-0450(2004)043<0264:AGATDN>2.0.CO;2","article-title":"A General Approach to Double-Moment Normalization of Drop Size Distributions","volume":"43","author":"Lee","year":"2004","journal-title":"J. Appl. Meteorol."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"1114","DOI":"10.1175\/1520-0469(2004)061<1114:AMIORR>2.0.CO;2","article-title":"A Microphysical Interpretation of Radar Reflectivity\u2013Rain Rate Relationships","volume":"61","author":"Steiner","year":"2004","journal-title":"J. Atmos. Sci."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"43","DOI":"10.1175\/1525-7541(2003)004<0043:VORSDI>2.0.CO;2","article-title":"Variability of Raindrop Size Distributions in a Squall Line and Implications for Radar Rainfall Estimation","volume":"4","author":"Uijlenhoet","year":"2003","journal-title":"J. Hydrometeorol."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"2238","DOI":"10.1175\/2008JAMC1732.1","article-title":"Analysis of Video Disdrometer and Polarimetric Radar Data to Characterize Rain Microphysics in Oklahoma","volume":"47","author":"Cao","year":"2008","journal-title":"J. Appl. Meteorol. Climatol."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"217","DOI":"10.1175\/1520-0450(2004)043<0217:PREBOA>2.0.CO;2","article-title":"Polarimetric Radar Estimators Based on a Constrained Gamma Drop Size Distribution Model","volume":"43","author":"Vivekanandan","year":"2004","journal-title":"J. Appl. Meteorol."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"438","DOI":"10.1016\/j.atmosres.2014.03.009","article-title":"Evaluation of X-Band Polarimetric Radar Estimation of Rainfall and Rain Drop Size Distribution Parameters in West Africa","volume":"143","author":"Koffi","year":"2014","journal-title":"Atmos. Res."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"633","DOI":"10.1175\/1520-0426(2002)019<0633:AMFETP>2.0.CO;2","article-title":"A Methodology for Estimating the Parameters of a Gamma Raindrop Size Distribution Model from Polarimetric Radar Data: Application to a Squall-Line Event from the TRMM\/Brazil Campaign","volume":"19","author":"Bringi","year":"2002","journal-title":"J. Atmos. Ocean. Technol."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"15862","DOI":"10.1038\/s41598-019-52028-5","article-title":"An Assessment of Tropical Cyclones Rainfall Erosivity for Taiwan","volume":"9","author":"Janapati","year":"2019","journal-title":"Sci. Rep."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"13312","DOI":"10.1029\/2019JD031011","article-title":"The Latitudinal Variability of Oceanic Rainfall Properties and Its Implication for Satellite Retrievals: 2. The Relationships Between Radar Observables and Drop Size Distribution Parameters","volume":"124","author":"Protat","year":"2019","journal-title":"JGR Atmos."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"13291","DOI":"10.1029\/2019JD031010","article-title":"The Latitudinal Variability of Oceanic Rainfall Properties and Its Implication for Satellite Retrievals: 1. Drop Size Distribution Properties","volume":"124","author":"Protat","year":"2019","journal-title":"JGR Atmos."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"1494","DOI":"10.1175\/1520-0450(1994)033<1494:AGFFRS>2.0.CO;2","article-title":"A General Formulation for Raindrop Size Distribution","volume":"33","author":"Torres","year":"1994","journal-title":"J. Appl. Meteorol."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"1118","DOI":"10.1175\/1520-0450(2001)040<1118:TCONDT>2.0.CO;2","article-title":"The Concept of \u201cNormalized\u201d Distribution to Describe Raindrop Spectra: A Tool for Cloud Physics and Cloud Remote Sensing","volume":"40","author":"Testud","year":"2001","journal-title":"J. Appl. Meteorol."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"270","DOI":"10.1175\/2008JAMC1877.1","article-title":"A Preliminary Analysis of Spatial Variability of Raindrop Size Distributions during Stratiform Rain Events","volume":"48","author":"Lee","year":"2009","journal-title":"J. Appl. Meteorol. Climatol."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"1773","DOI":"10.1175\/1520-0426(2001)018<1773:REFPRM>2.0.CO;2","article-title":"Rainfall Estimation from Polarimetric Radar Measurements: Composite Algorithms Immune to Variability in Raindrop Shape\u2013Size Relation","volume":"18","author":"Gorgucci","year":"2001","journal-title":"J. Atmos. Ocean. Technol."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"2373","DOI":"10.1175\/1520-0469(2002)059<2373:EORSDP>2.0.CO;2","article-title":"Estimation of Raindrop Size Distribution Parameters from Polarimetric Radar Measurements","volume":"59","author":"Gorgucci","year":"2002","journal-title":"J. Atmos. Sci."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"1829","DOI":"10.1175\/2009JTECHA1183.1","article-title":"Can a Unique Model Describe the Raindrop Shape\u2013Size Relation? A Clue from Polarimetric Radar Measurements","volume":"26","author":"Gorgucci","year":"2009","journal-title":"J. Atmos. Ocean. Technol."},{"key":"ref_19","first-page":"830","article-title":"A Method For Estimating Rain Rate And Drop Size Distribution From Polarimetric Radar Measurements","volume":"4","author":"Zhang","year":"2021","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"461","DOI":"10.1175\/1520-0450(2004)043<0461:DSDRWP>2.0.CO;2","article-title":"Drop Size Distribution Retrieval with Polarimetric Radar: Model and Application","volume":"43","author":"Brandes","year":"2004","journal-title":"J. Appl. Meteorol."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"1265","DOI":"10.1175\/2010JTECHA1407.1","article-title":"Retrieval of Three-Dimensional Raindrop Size Distribution Using X-Band Polarimetric Radar Data","volume":"27","author":"Kim","year":"2010","journal-title":"J. Atmos. Ocean. Technol."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"3067","DOI":"10.1109\/TGRS.2008.2000757","article-title":"Evaluation of X-Band Polarimetric-Radar Estimates of Drop-Size Distributions From Coincident S-Band Polarimetric Estimates and Measured Raindrop Spectra","volume":"46","author":"Anagnostou","year":"2008","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"2573","DOI":"10.5194\/amt-10-2573-2017","article-title":"Retrieval of the Raindrop Size Distribution from Polarimetric Radar Data Using Double-Moment Normalisation","volume":"10","author":"Raupach","year":"2017","journal-title":"Atmos. Meas. Tech."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"20","DOI":"10.1016\/j.cageo.2012.05.028","article-title":"Tree-Based Genetic Programming Approach to Infer Microphysical Parameters of the DSDs from the Polarization Diversity Measurements","volume":"48","author":"Islam","year":"2012","journal-title":"Comput. Geosci."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"973","DOI":"10.1175\/2009JAMC2227.1","article-title":"Polarimetric Radar Rain Estimation through Retrieval of Drop Size Distribution Using a Bayesian Approach","volume":"49","author":"Cao","year":"2010","journal-title":"J. Appl. Meteorol. Climatol."},{"key":"ref_26","doi-asserted-by":"crossref","unstructured":"Wen, G., Chen, H., Zhang, G., and Sun, J. (2018). An Inverse Model for Raindrop Size Distribution Retrieval with Polarimetric Variables. Remote Sens., 10.","DOI":"10.3390\/rs10081179"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.atmosres.2008.03.001","article-title":"Correction of X-Band Radar Reflectivity and Differential Reflectivity for Rain Attenuation Using Differential Phase","volume":"90","author":"Kim","year":"2008","journal-title":"Atmos. Res."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"1633","DOI":"10.1175\/JTECH1804.1","article-title":"Correction of Radar Reflectivity and Differential Reflectivity for Rain Attenuation at X Band. Part II: Evaluation and Application","volume":"22","author":"Park","year":"2005","journal-title":"J. Atmos. Ocean. Technol."},{"key":"ref_29","doi-asserted-by":"crossref","unstructured":"Shi, Z., Chen, H., Chandrasekar, V., and He, J. (2017). Deployment and Performance of an X-Band Dual-Polarization Radar during the Southern China Monsoon Rainfall Experiment. Atmosphere, 9.","DOI":"10.3390\/atmos9010004"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"1906","DOI":"10.1109\/36.951081","article-title":"Correcting C-Band Radar Reflectivity and Differential Reflectivity Data for Rain Attenuation: A Self-Consistent Method with Constraints","volume":"39","author":"Bringi","year":"2001","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"332","DOI":"10.1175\/1520-0426(2000)017<0332:TRPAAT>2.0.CO;2","article-title":"The Rain Profiling Algorithm Applied to Polarimetric Weather Radar","volume":"17","author":"Testud","year":"2000","journal-title":"J. Atmos. Ocean. Technol."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"941","DOI":"10.1175\/1520-0450(2002)041<0941:XBPRMO>2.0.CO;2","article-title":"X-Band Polarimetric Radar Measurements of Rainfall","volume":"41","author":"Matrosov","year":"2002","journal-title":"J. Appl. Meteorol."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"1369","DOI":"10.1109\/TGRS.2013.2250979","article-title":"Evaluation of a New Polarimetric Algorithm for Rain-Path Attenuation Correction of X-Band Radar Observations Against Disdrometer","volume":"52","author":"Kalogiros","year":"2014","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"32","DOI":"10.1016\/j.atmosres.2019.03.006","article-title":"An Improved Self-Consistent Approach to Attenuation Correction for C-Band Polarimetric Radar Measurements and Its Impact on Quantitative Precipitation Estimation","volume":"226","author":"Gou","year":"2019","journal-title":"Atmos. Res."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"243","DOI":"10.1002\/qj.556","article-title":"Rain Drop Size Distribution Variability and Impact on X-Band Polarimetric Radar Retrieval: Results from the AMMA Campaign in Benin","volume":"136","author":"Gosset","year":"2010","journal-title":"Q. J. R. Meteorol. Soc."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"248","DOI":"10.1175\/JHM424.1","article-title":"The Utility of X-Band Polarimetric Radar for Quantitative Estimates of Rainfall Parameters","volume":"6","author":"Matrosov","year":"2005","journal-title":"J. Hydrometeorol."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"1099","DOI":"10.1175\/JAMC-D-13-0191.1","article-title":"Estimation of X-Band Polarimetric Radar Attenuation and Measurement Uncertainty Using a Variational Method","volume":"53","author":"Chang","year":"2014","journal-title":"J. Appl. Meteorol. Climatol."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"387","DOI":"10.1175\/JTECH-D-12-00248.1","article-title":"Raindrop Size Distribution (DSD) Retrieval for X-Band Dual-Polarization Radar","volume":"31","author":"Yoshikawa","year":"2014","journal-title":"J. Atmos. Ocean. Technol."},{"key":"ref_39","doi-asserted-by":"crossref","unstructured":"Tarantola, A. (2005). Inverse Problem Theory and Methods for Model Parameter Estimation, Society for Industrial and Applied Mathematics.","DOI":"10.1137\/1.9780898717921"},{"key":"ref_40","unstructured":"Menke, W. (2018). Geophysical Data Analysis: Discrete Inverse Theory, Academic Press. [4th ed.]."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"8","DOI":"10.1002\/qj.486","article-title":"The AMMA Field Campaigns: Multiscale and Multidisciplinary Observations in the West African Region","volume":"136","author":"Lebel","year":"2010","journal-title":"Q. J. R. Meteorol. Soc."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"143","DOI":"10.1016\/j.jhydrol.2009.01.011","article-title":"The Organization and Kinematics of Tropical Rainfall Systems Ground Tracked at Mesoscale with Gages: First Results from the Campaigns 1999\u20132006 on the Upper Ou\u00e9m\u00e9 Valley (Benin)","volume":"375","author":"Depraetere","year":"2009","journal-title":"J. Hydrol."},{"key":"ref_43","doi-asserted-by":"crossref","unstructured":"Moumouni, S., Gosset, M., and Houngninou, E. (2008). Main Features of Rain Drop Size Distributions Observed in Benin, West Africa, with Optical Disdrometers. Geophys. Res. Lett., 35.","DOI":"10.1029\/2008GL035755"},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"231","DOI":"10.1175\/JAMC-D-15-0013.1","article-title":"Characterization of Hydrometeors in Sahelian Convective Systems with an X-Band Radar and Comparison with in Situ Measurements. Part I: Sensitivity of Polarimetric Radar Particle Identification Retrieval and Case Study Evaluation","volume":"55","author":"Cazenave","year":"2016","journal-title":"J. Appl. Meteorol. Climatol."},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"643","DOI":"10.1175\/1520-0426(1995)012<0643:AIFTFT>2.0.CO;2","article-title":"An Iterative Filtering Technique for the Analysis of Copolar Differential Phase and Dual-Frequency Radar Measurements","volume":"12","author":"Hubbert","year":"1995","journal-title":"J. Atmos. Ocean. Technol."},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"110","DOI":"10.1016\/j.jhydrol.2005.11.048","article-title":"A Dual-Beam Spectropluviometer Concept","volume":"328","author":"Delahaye","year":"2006","journal-title":"J. Hydrol."},{"key":"ref_47","unstructured":"Moumouni, S. (2009). Analyse Des Distributions Granulom\u00e9triques Des Pluies Au B\u00e9nin: Caract\u00e9ristiques Globales, Variabilit\u00e9 et Application \u00e0 La Mesure Radar. [Ph.D. Thesis, Ecole Normale Sup\u00e9rieure Natitingou, Universit\u00e9 de Parakou]."},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"355","DOI":"10.1175\/1520-0450(1996)035<0355:EFTRSO>2.0.CO;2","article-title":"Evidence from Tropical Raindrop Spectra of the Origin of Rain from Stratiform versus Convective Clouds","volume":"35","author":"Tokay","year":"1996","journal-title":"J. Appl. Meteorol."},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"251","DOI":"10.1175\/JAMC-D-15-0014.1","article-title":"Characterization of Hydrometeors in Sahelian Convective Systems with an X-Band Radar and Comparison with in Situ Measurements. Part II: A Simple Brightband Method to Infer the Density of Icy Hydrometeors","volume":"55","author":"Alcoba","year":"2016","journal-title":"J. Appl. Meteorol. Climatol."},{"key":"ref_50","doi-asserted-by":"crossref","first-page":"2529","DOI":"10.1175\/JAMC-D-13-0124.1","article-title":"Backscatter Differential Phase\u2014Estimation and Variability","volume":"52","author":"Kumjian","year":"2013","journal-title":"J. Appl. Meteorol. Climatol."},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"1716","DOI":"10.1175\/JTECH-D-12-00147.1","article-title":"An Application of Linear Programming to Polarimetric Radar Differential Phase Processing","volume":"30","author":"Giangrande","year":"2013","journal-title":"J. Atmos. Ocean. Technol."},{"key":"ref_52","doi-asserted-by":"crossref","first-page":"711","DOI":"10.1175\/JTECH-D-10-05053.1","article-title":"An Extended Kalman Filter Framework for Polarimetric X-Band Weather Radar Data Processing","volume":"29","author":"Schneebeli","year":"2012","journal-title":"J. Atmos. Ocean. Technol."},{"key":"ref_53","doi-asserted-by":"crossref","first-page":"988","DOI":"10.1109\/LGRS.2011.2145354","article-title":"Estimation of Specific Differential Phase and Differential Backscatter Phase From Polarimetric Weather Radar Measurements of Rain","volume":"8","author":"Otto","year":"2011","journal-title":"IEEE Geosci. Remote Sens. Lett."},{"key":"ref_54","doi-asserted-by":"crossref","first-page":"555","DOI":"10.1175\/JTECH-D-17-0105.1","article-title":"Adaptive and High-Resolution Estimation of Specific Differential Phase for Polarimetric X-Band Weather Radars","volume":"35","author":"Unal","year":"2018","journal-title":"J. Atmos. Ocean. Technol."},{"key":"ref_55","doi-asserted-by":"crossref","unstructured":"Bringi, V.N., and Chandrasekar, V. (2001). Polarimetric Doppler Weather Radar: Principles and Applications, Cambridge University Press.","DOI":"10.1017\/CBO9780511541094"},{"key":"ref_56","doi-asserted-by":"crossref","first-page":"396","DOI":"10.1016\/j.atmosres.2010.02.001","article-title":"A New Understanding of Raindrop Shape","volume":"97","author":"Beard","year":"2010","journal-title":"Atmos. Res."},{"key":"ref_57","doi-asserted-by":"crossref","first-page":"416","DOI":"10.1016\/j.atmosres.2010.03.024","article-title":"Shapes and Oscillations of Falling Raindrops\u2014A Review","volume":"97","author":"Mitra","year":"2010","journal-title":"Atmos. Res."},{"key":"ref_58","doi-asserted-by":"crossref","first-page":"3033","DOI":"10.1175\/JAS3781.1","article-title":"What Is the Shape of a Raindrop? An Answer from Radar Measurements","volume":"63","author":"Gorgucci","year":"2006","journal-title":"J. Atmos. Sci."},{"key":"ref_59","doi-asserted-by":"crossref","first-page":"2673","DOI":"10.1175\/1520-0469(1999)056<2673:LMOARF>2.0.CO;2","article-title":"Laboratory Measurements of Axis Ratios for Large Raindrops","volume":"56","author":"Andsager","year":"1999","journal-title":"J. Atmos. Sci."},{"key":"ref_60","doi-asserted-by":"crossref","first-page":"535","DOI":"10.1016\/0022-4073(96)00002-7","article-title":"T-Matrix Computations of Light Scattering by Nonspherical Particles: A Review","volume":"55","author":"Mishchenko","year":"1996","journal-title":"J. Quant. Spectrosc. Radiat. Transf."},{"key":"ref_61","doi-asserted-by":"crossref","first-page":"805","DOI":"10.1109\/PROC.1965.4058","article-title":"Matrix Formulation of Electromagnetic Scattering","volume":"53","author":"Waterman","year":"1965","journal-title":"Proc. IEEE"},{"key":"ref_62","doi-asserted-by":"crossref","first-page":"825","DOI":"10.1103\/PhysRevD.3.825","article-title":"Symmetry, Unitarity, and Geometry in Electromagnetic Scattering","volume":"3","author":"Waterman","year":"1971","journal-title":"Phys. Rev. D"},{"key":"ref_63","doi-asserted-by":"crossref","first-page":"219","DOI":"10.1029\/RG020i002p00219","article-title":"Generalized Nonlinear Inverse Problems Solved Using the Least Squares Criterion","volume":"20","author":"Tarantola","year":"1982","journal-title":"Rev. Geophys."},{"key":"ref_64","doi-asserted-by":"crossref","first-page":"621","DOI":"10.1175\/JTECH-D-19-0085.1","article-title":"Rainfall and DSD Parameters Comparison between Micro Rain Radar, Two-Dimensional Video and Parsivel2 Disdrometers, and S-Band Dual-Polarization Radar","volume":"37","author":"Adirosi","year":"2020","journal-title":"J. Atmos. Ocean. Technol."},{"key":"ref_65","doi-asserted-by":"crossref","first-page":"753","DOI":"10.1175\/JHM-D-16-0127.1","article-title":"On the Optimal Measuring Area for Pointwise Rainfall Estimation: A Dedicated Experiment with 14 Laser Disdrometers","volume":"18","author":"Tapiador","year":"2017","journal-title":"J. Hydrometeorol."}],"container-title":["Remote Sensing"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-4292\/14\/5\/1116\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T22:26:44Z","timestamp":1760135204000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-4292\/14\/5\/1116"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2022,2,24]]},"references-count":65,"journal-issue":{"issue":"5","published-online":{"date-parts":[[2022,3]]}},"alternative-id":["rs14051116"],"URL":"https:\/\/doi.org\/10.3390\/rs14051116","relation":{},"ISSN":["2072-4292"],"issn-type":[{"type":"electronic","value":"2072-4292"}],"subject":[],"published":{"date-parts":[[2022,2,24]]}}}