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 <front>
  <journal-meta>
   <journal-id journal-id-type="publisher-id">Russian Journal of Earth Sciences</journal-id>
   <journal-title-group>
    <journal-title xml:lang="en">Russian Journal of Earth Sciences</journal-title>
    <trans-title-group xml:lang="ru">
     <trans-title>Russian Journal of Earth Sciences</trans-title>
    </trans-title-group>
   </journal-title-group>
   <issn publication-format="online">1681-1208</issn>
  </journal-meta>
  <article-meta>
   <article-id pub-id-type="publisher-id">96038</article-id>
   <article-id pub-id-type="doi">10.2205/2025es001017</article-id>
   <article-id pub-id-type="edn">kzhtur</article-id>
   <article-categories>
    <subj-group subj-group-type="toc-heading" xml:lang="ru">
     <subject>ОРИГИНАЛЬНЫЕ СТАТЬИ</subject>
    </subj-group>
    <subj-group subj-group-type="toc-heading" xml:lang="en">
     <subject>ORIGINAL ARTICLES</subject>
    </subj-group>
    <subj-group>
     <subject>ОРИГИНАЛЬНЫЕ СТАТЬИ</subject>
    </subj-group>
   </article-categories>
   <title-group>
    <article-title xml:lang="en">Numerical Simulation of Radar Signal Reflected by Sea Surface with Different Sea Ice Concentration</article-title>
    <trans-title-group xml:lang="ru">
     <trans-title>Численное моделирование радиолокационного сигнала, отражённого морской поверхностью с разной сплочённостью морского льда</trans-title>
    </trans-title-group>
   </title-group>
   <contrib-group content-type="authors">
    <contrib contrib-type="author">
     <contrib-id contrib-id-type="orcid">https://orcid.org/0000-0001-7762-7731</contrib-id>
     <name-alternatives>
      <name xml:lang="ru">
       <surname>Титченко</surname>
       <given-names>Юрий Андреевич</given-names>
      </name>
      <name xml:lang="en">
       <surname>Titchenko</surname>
       <given-names>Yuriy Andreevich</given-names>
      </name>
     </name-alternatives>
     <email>yuriy@ipfran.ru</email>
     <bio xml:lang="ru">
      <p>кандидат физико-математических наук;</p>
     </bio>
     <bio xml:lang="en">
      <p>candidate of physical and mathematical sciences;</p>
     </bio>
     <xref ref-type="aff" rid="aff-1"/>
    </contrib>
    <contrib contrib-type="author">
     <contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-4054-4905</contrib-id>
     <name-alternatives>
      <name xml:lang="ru">
       <surname>Караев</surname>
       <given-names>Владимир Юрьевич</given-names>
      </name>
      <name xml:lang="en">
       <surname>Karaev</surname>
       <given-names>Vladimir Yur'evich</given-names>
      </name>
     </name-alternatives>
     <email>volody@ipfran.ru</email>
     <xref ref-type="aff" rid="aff-2"/>
    </contrib>
    <contrib contrib-type="author">
     <contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-3795-0347</contrib-id>
     <name-alternatives>
      <name xml:lang="ru">
       <surname>Панфилова</surname>
       <given-names>Мария Андреевна</given-names>
      </name>
      <name xml:lang="en">
       <surname>Panfilova</surname>
       <given-names>Mariya Andreevna</given-names>
      </name>
     </name-alternatives>
     <xref ref-type="aff" rid="aff-1"/>
    </contrib>
    <contrib contrib-type="author">
     <contrib-id contrib-id-type="orcid">https://orcid.org/0000-0003-3189-7095</contrib-id>
     <name-alternatives>
      <name xml:lang="ru">
       <surname>Понур</surname>
       <given-names>Кирилл Александрович</given-names>
      </name>
      <name xml:lang="en">
       <surname>Ponur</surname>
       <given-names>Kirill Aleksandrovich</given-names>
      </name>
     </name-alternatives>
     <xref ref-type="aff" rid="aff-3"/>
    </contrib>
    <contrib contrib-type="author">
     <contrib-id contrib-id-type="orcid">https://orcid.org/0009-0009-5114-2125</contrib-id>
     <name-alternatives>
      <name xml:lang="ru">
       <surname>Кузнецов</surname>
       <given-names>Ярослав Александрович</given-names>
      </name>
      <name xml:lang="en">
       <surname>Kuznetsov</surname>
       <given-names>Yaroslav Aleksandrovich</given-names>
      </name>
     </name-alternatives>
     <xref ref-type="aff" rid="aff-4"/>
    </contrib>
    <contrib contrib-type="author">
     <contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-5353-7528</contrib-id>
     <name-alternatives>
      <name xml:lang="ru">
       <surname>Мешков</surname>
       <given-names>Евгений Михайлович</given-names>
      </name>
      <name xml:lang="en">
       <surname>Meshkov</surname>
       <given-names>Evgeniy Mihaylovich</given-names>
      </name>
     </name-alternatives>
     <xref ref-type="aff" rid="aff-1"/>
    </contrib>
   </contrib-group>
   <aff-alternatives id="aff-1">
    <aff>
     <institution xml:lang="ru">Федеральный исследовательский центр Институт прикладной физики Российской академии наук</institution>
     <city>Nizhny Novgorod</city>
     <country>RU</country>
    </aff>
    <aff>
     <institution xml:lang="en">Institute of Applied Physics</institution>
     <city>Nizhny Novgorod</city>
     <country>RU</country>
    </aff>
   </aff-alternatives>
   <aff-alternatives id="aff-2">
    <aff>
     <institution xml:lang="ru">Федеральный исследовательский центр Институт прикладной физики им. А.В. Гапонова-Грехова Российской академии наук</institution>
     <country>Россия</country>
    </aff>
    <aff>
     <institution xml:lang="en">Federal Research Center A.V. Gaponov-Grekhov Institute of Applied Physics of the Russian Academy of Sciences</institution>
     <country>Russian Federation</country>
    </aff>
   </aff-alternatives>
   <aff-alternatives id="aff-3">
    <aff>
     <institution xml:lang="ru">Федеральный исследовательский центр Институт прикладной физики им. А.В. Гапонова-Грехова Российской академии наук</institution>
     <country>Россия</country>
    </aff>
    <aff>
     <institution xml:lang="en">Federal Research Center A.V. Gaponov-Grekhov Institute of Applied Physics of the Russian Academy of Sciences</institution>
     <country>Russian Federation</country>
    </aff>
   </aff-alternatives>
   <aff-alternatives id="aff-4">
    <aff>
     <institution xml:lang="ru">Национальный исследовательский Нижегородский государственный университет им. Н. И. Лобачевского</institution>
     <country>Россия</country>
    </aff>
    <aff>
     <institution xml:lang="en">National Research Lobachevsky State University of Nizhny Novgorod</institution>
     <country>Russian Federation</country>
    </aff>
   </aff-alternatives>
   <pub-date publication-format="print" date-type="pub" iso-8601-date="2025-05-03T00:00:00+03:00">
    <day>03</day>
    <month>05</month>
    <year>2025</year>
   </pub-date>
   <pub-date publication-format="electronic" date-type="pub" iso-8601-date="2025-05-03T00:00:00+03:00">
    <day>03</day>
    <month>05</month>
    <year>2025</year>
   </pub-date>
   <volume>25</volume>
   <issue>3</issue>
   <fpage>1</fpage>
   <lpage>11</lpage>
   <history>
    <date date-type="received" iso-8601-date="2025-03-11T00:00:00+03:00">
     <day>11</day>
     <month>03</month>
     <year>2025</year>
    </date>
    <date date-type="accepted" iso-8601-date="2025-04-25T00:00:00+03:00">
     <day>25</day>
     <month>04</month>
     <year>2025</year>
    </date>
   </history>
   <self-uri xlink:href="https://rjes.ru/en/nauka/article/96038/view">https://rjes.ru/en/nauka/article/96038/view</self-uri>
   <abstract xml:lang="ru">
    <p>В настоящее время активно развиваются методы радиолокационного дистанционного зондирования при малых углах падения (от вертикали до 15∘). Важным приложением этих методов является определение наличия и сплочённости морского льда. В данной работе представлен подход численного моделирования, в рамках которого моделируется отражающая поверхность с различной сплочённостью морского льда, и затем моделируются характеристики радиолокационного сигнала, отражённого этой поверхностью при заданной геометрии измерений. Без потери общности в данной работе будем рассматривать конкретную геометрию радиолокатора DPR (Dual-frequency Precipitation Radar) на спутнике миссии GPM (Global Precipitation Measurement) и только Ku-диапазон этого радиолокатора. Сигнал, отражённый морским волнением, будет рассчитываться в рамках приближения Кирхгофа. Поскольку общепризнанной модели для сигнала, рассеянного поверхностью морского льда при малых углах падения нет, то в качестве модели будет использоваться эмпирическая формула, полученная по данным DPR. В работе обсуждается метод определения сплочённости морского льда по данным радиолокационного зондирования при малых углах падения.</p>
   </abstract>
   <trans-abstract xml:lang="en">
    <p>Currently, methods of radar remote sensing at small incidence angles (from the vertical to 15∘) are actively developed. An important application of these methods is the determination of the presence and sea ice concentration. This paper presents an approach to numerical simulation of an experiment in which a reflecting surface with different sea ice concentrations is modeled and then the characteristics of the radar signal reflected by this surface for a given measurement geometry are modeled. Without loss of generality, in this paper we will consider a specific geometry of the DPR (Dual-frequency Precipitation Radar) radar on the GPM (Global Precipitation Measurement) mission satellite and only the Ku-band of this radar. The signal reflected by sea waves will be calculated within the Kirchhoff approximation. Since there is no generally accepted model for the signal scattered by the sea ice at small incidence angles, an empirical formula obtained from DPR data will be used as a model. The paper discusses a method for determining sea ice concentration using radar sensing data at low incidence angles.</p>
   </trans-abstract>
   <kwd-group xml:lang="ru">
    <kwd>морской лёд</kwd>
    <kwd>морское волнение</kwd>
    <kwd>сечение обратного рассеяния</kwd>
    <kwd>малые углы падения</kwd>
    <kwd>квазизеркальное отражение</kwd>
    <kwd>сплочённость морского льда</kwd>
   </kwd-group>
   <kwd-group xml:lang="en">
    <kwd>sea ice</kwd>
    <kwd>sea waves</kwd>
    <kwd>backscattering cross section</kwd>
    <kwd>small incidence angles</kwd>
    <kwd>quasi-specular reflection</kwd>
    <kwd>sea ice concentration</kwd>
   </kwd-group>
   <funding-group>
    <funding-statement xml:lang="ru">Исследование выполнено за счёт гранта Российского научного фонда №23-77-10064, https://rscf.ru/project/23-77-10064/. Авторы благодарят анонимных рецензентов за ценные замечания, что позволило существенно улучшить работу.</funding-statement>
    <funding-statement xml:lang="en">The study was supported by the Russian Science Foundation grant No. 23-77-10064, https://rscf.ru/project/23-77-10064/. The authors thank the anonymous reviewers for their valuable comments, which allowed them to significantly improve the work.</funding-statement>
   </funding-group>
  </article-meta>
 </front>
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