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<article article-type="research-article" dtd-version="1.3" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xml:lang="ru"><front><journal-meta><journal-id journal-id-type="publisher-id">geology</journal-id><journal-title-group><journal-title xml:lang="ru">Известия высших учебных заведений. Геология и разведка</journal-title><trans-title-group xml:lang="en"><trans-title>Proceedings of higher educational establishments. Geology and Exploration</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">0016-7762</issn><issn pub-type="epub">2618-8708</issn><publisher><publisher-name>Sergo Ordzhonikidze Russian State University for Geological Prospecting</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.32454/0016-7762-2025-67-4-87-101</article-id><article-id custom-type="elpub" pub-id-type="custom">geology-1232</article-id><article-categories><subj-group subj-group-type="heading"><subject>Research Article</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="ru"><subject>ГЕОФИЗИЧЕСКИЕ МЕТОДЫ ПОИСКОВ И РАЗВЕДКИ</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="en"><subject>GEOPHYSICAL METHODS OF PROSPECTING AND EXPLORATION</subject></subj-group></article-categories><title-group><article-title>Применение модификационного преобразования Фурье для моделирования вариаций поля силы тяжести</article-title><trans-title-group xml:lang="en"><trans-title>Application of a modified fou rier transformation for modeling variations in the gravity field</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0003-2931-4428</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Нигматуллин</surname><given-names>Р. Р.</given-names></name><name name-style="western" xml:lang="en"><surname>Nigmatullin</surname><given-names>R. R.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Нигматуллин Равиль Рашидович — доктор физико-математических наук, профессор</p><p>10, ул. К. Маркса, г. Казань, 420111</p></bio><bio xml:lang="en"><p>Raoul R. Nigmatullin — Dr. Sci. (Phys.-Math.), Professor</p><p>10, K. Marx str., Kazan, 420111</p></bio><email xlink:type="simple">renigmat@gmail.com</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0009-0005-0083-9441</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Белов</surname><given-names>А. П.</given-names></name><name name-style="western" xml:lang="en"><surname>Belov</surname><given-names>A. P.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Белов Алексей Павлович — кандидат геолого-минералогических наук, доцент</p><p>23, ул. Миклухо-Маклая, г. Москва 117997</p><p>тел.: +7 (495) 255-15-10, доб. 21-52</p></bio><bio xml:lang="en"><p>Alexey P. Belov — Cand. Sci. (Geol.-Mineral.), Assoc. Prof.</p><p>23, Miklukho-Maklaya str., Moscow 117997</p><p>tel.: +7 (495) 255-15-10, ext. 21-52</p></bio><email xlink:type="simple">belovap@mgri.ru</email><xref ref-type="aff" rid="aff-2"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0001-9772-1821</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Ерохин</surname><given-names>А. М.</given-names></name><name name-style="western" xml:lang="en"><surname>Erokhin</surname><given-names>A. M.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Ерохин Александр Михайлович — заместитель начальника управления ИТ по научно-исследовательской работе</p><p>4, корп. 2, ул. Макарова, г. Тверь 170002</p><p>тел.: + 7 (915) 724-82-76</p></bio><bio xml:lang="en"><p>Alexandr M. Erokhin — Deputy Head of the IT Department for Research and Development</p><p>4, bld. 2, Makarova str., Tver, 170002</p><p>tel.: + 7 (915) 724-82-76</p></bio><email xlink:type="simple">erokhin_am@petroviser.ru</email><xref ref-type="aff" rid="aff-3"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0009-0000-3283-7495</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Петров</surname><given-names>А. В.</given-names></name><name name-style="western" xml:lang="en"><surname>Petrov</surname><given-names>A. V.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Петров Алексей Владимирович — доктор физико-математических наук, профессор факультета геологии и геофизики нефти и газа</p><p>23, ул. Миклухо-Маклая, г. Москва 117997</p><p>тел.: +7 (916) 604-55-01</p></bio><bio xml:lang="en"><p>Alexey V. Petrov — Dr. Sci. (Phys. and Math.), Prof., Faculty of Geology and Geophysics of Oil and Gas</p><p>23, Miklukho-Maklaya str., Moscow 117997</p><p>tel.: +7 (916) 604-55-01</p></bio><email xlink:type="simple">petrovstud@mail.ru</email><xref ref-type="aff" rid="aff-2"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru"><institution>ФГБОУ ВО «Казанский национальный исследовательский технический университет» им. А.Н. Туполева (КНИТУ-КАИ)</institution><country>Россия</country></aff><aff xml:lang="en"><institution>A.N. Tupolev Kazan National Research Technical University (KNRTU-KAI)</institution><country>Russian Federation</country></aff></aff-alternatives><aff-alternatives id="aff-2"><aff xml:lang="ru"><institution>ФГБОУ ВО «Российский государственный геологоразведочный университет имени Серго Орджоникидзе»</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Sergo Ordzhonikidze Russian State University for Geological Prospecting</institution><country>Russian Federation</country></aff></aff-alternatives><aff-alternatives id="aff-3"><aff xml:lang="ru"><institution>ООО «Петровайзер»</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Petroviser LLC</institution><country>Russian Federation</country></aff></aff-alternatives><pub-date pub-type="collection"><year>2025</year></pub-date><pub-date pub-type="epub"><day>02</day><month>01</month><year>2026</year></pub-date><volume>67</volume><issue>4</issue><fpage>87</fpage><lpage>101</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Нигматуллин Р.Р., Белов А.П., Ерохин А.М., Петров А.В., 2025</copyright-statement><copyright-year>2025</copyright-year><copyright-holder xml:lang="ru">Нигматуллин Р.Р., Белов А.П., Ерохин А.М., Петров А.В.</copyright-holder><copyright-holder xml:lang="en">Nigmatullin R.R., Belov A.P., Erokhin A.M., Petrov A.V.</copyright-holder><license xml:lang="ru" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>Данная работа распространяется под лицензией Creative Commons Attribution 4.0.</license-p></license><license xml:lang="en" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>This work is licensed under a Creative Commons Attribution 4.0 License.</license-p></license></permissions><self-uri xlink:href="https://www.geology-mgri.ru/jour/article/view/1232">https://www.geology-mgri.ru/jour/article/view/1232</self-uri><abstract><sec><title>Введение</title><p>Введение. Анализ и обработка сигналов со сложной структурой, в частности частотно-фазовой модуляцией, представляет собой актуальную задачу, особенно в тех случаях, когда традиционные методы не обеспечивают достаточной точности. В работе рассматривается модифицированное Фурье-преобразование, подходящее для обработки сигналов с модулированными частотой и фазой, которые в статье обозначаются как частотно-фазово модулированные сигналы.</p></sec><sec><title>Цель</title><p>Цель. Разработка и применение модифицированного Фурье-преобразования для получения амплитудно-частотных характеристик (АЧХ) сигналов с целью повышения точности подгонки сигналов и решения задач, связанных с моделированием откликов сложных систем.</p></sec><sec><title>Материалы и методы</title><p>Материалы и методы. Предложенное преобразование применяется напрямую к сигналу и благодаря своей строго периодической структуре позволяет получить АЧХ с высокой точностью. Метод был апробирован на гравиметрических данных, полученных с приборов ГНУ-KВ и CG-6. Эти данные представляют собой временные вариации гравитационного поля без тренда, что традиционно затрудняет их описание и интерпретацию.</p></sec><sec><title>Результаты</title><p>Результаты. Показано, что предложенное преобразование эффективно справляется с задачей нахождения АЧХ ЧФМ-сигналов, включая те, что непосредственно присутствуют в структуре преобразования. Полученные результаты демонстрируют высокую точность подгонки, открывая новые возможности для анализа сложных систем без необходимости создания подробных физических моделей.</p></sec><sec><title>Заключение</title><p>Заключение. Модифицированное Фурье-преобразование может служить полезным инструментом для построения подгоночных функций в форме АЧХ при исследовании сложных систем. В гравиметрии это открывает новые перспективы как для фундаментальных исследований, так и для решения прикладных геолого-геофизических задач.</p></sec></abstract><trans-abstract xml:lang="en"><sec><title>Introduction</title><p>Introduction. The analysis and processing of signals with complex structures — particularly those exhibiting frequency and phase modulation — remains a relevant challenge, especially in cases where traditional methods fail to provide sufficient accuracy. This study considers a modified Fourier transformation suitable for processing signals with modulated frequency and phase, referred to in the article as frequency-phase modulated (FPM) signals.</p></sec><sec><title>Objective</title><p>Objective. To develop and apply a modified Fourier transformation for obtaining the amplitude-frequency characteristics (AFC) of FPM signals, aiming to improve the accuracy of signal fitting and to address problems related to modeling the responses of complex systems.</p></sec><sec><title>Materials and methods</title><p>Materials and methods. The proposed transformation is applied directly to FPM signals and, due to its strictly periodic structure, enables the accurate determination of their AFC. The method was tested on gravimetric data acquired using the GNU-KB and CG-6 gravimeters. These data represent detrended temporal fluctuations of the gravity field, which are typically difficult to describe and interpret using conventional methods.</p></sec><sec><title>Results</title><p>Results. It has been demonstrated that the proposed transformation effectively addresses the problem of determining the AFC of FPM signals, including those embedded within the transformation itself. The results show a high degree of fitting accuracy, thereby offering new opportunities for analyzing the responses of complex systems without the need for detailed physical modeling.</p></sec><sec><title>Conclusion</title><p>Conclusion. The modified Fourier transformation may serve as a valuable tool for constructing fitting functions in the form of AFCs when studying complex systems. In gravimetry, this approach opens new prospects for both fundamental research and the solution of applied geological and geophysical problems.</p></sec></trans-abstract><kwd-group xml:lang="ru"><kwd>частотно-фазовый модулированный сигнал (ЧФМ)</kwd><kwd>амплитудно-частотная характеристика (АЧХ)</kwd><kwd>временные вариации гравитационного поля</kwd><kwd>гравиметры</kwd></kwd-group><kwd-group xml:lang="en"><kwd>frequency-phase modulated signal (FPM)</kwd><kwd>amplitude-frequency characteristic (AFC)</kwd><kwd>temporal gravity field variations</kwd><kwd>gravimeters</kwd></kwd-group></article-meta></front><back><ref-list><title>References</title><ref id="cit1"><label>1</label><citation-alternatives><mixed-citation xml:lang="ru">Лобанов А.М., Белов А.П., Ерохин А.М., Венедиктов К.В. Алгоритм распознавания видеофайла для оцифровки колебаний аналогового индикатора на примере кварцевого гравиметра ГНУ-КВ. Известия высших учебных заведений. Геология и разведка. 2024. № 66(1). С. 128—134. 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