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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">radioelectronics</journal-id><journal-title-group><journal-title xml:lang="ru">Известия высших учебных заведений России. Радиоэлектроника</journal-title><trans-title-group xml:lang="en"><trans-title>Journal of the Russian Universities. Radioelectronics</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">1993-8985</issn><issn pub-type="epub">2658-4794</issn><publisher><publisher-name>Saint Petersburg Electrotechnical University</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.32603/1993-8985-2022-25-4-6-22</article-id><article-id custom-type="elpub" pub-id-type="custom">radioelectronics-658</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>РАДИОТЕХНИЧЕСКИЕ СРЕДСТВА ПЕРЕДАЧИ, ПРИЕМА И ОБРАБОТКИ СИГНАЛОВ</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="en"><subject>RADIO ELECTRONIC FACILITIES FOR SIGNAL TRANSMISSION, RECEPTION AND PROCESSING</subject></subj-group></article-categories><title-group><article-title>Оптимизация формы сигналов с квадратурной амплитудной модуляцией с использованием критерия заданной скорости спада уровня внеполосных излучений</article-title><trans-title-group xml:lang="en"><trans-title>Optimizing the Shape of Signals with Quadrature Amplitude Modulation According to the Criterion of Given Reduction Rate of Out-of-Band Emissions</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0001-7006-9634</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Макаров</surname><given-names>С. Б.</given-names></name><name name-style="western" xml:lang="en"><surname>Makarov</surname><given-names>S. B.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Макаров Сергей Борисович – доктор технических наук (1991), профессор (1994) Высшей школы прикладной физики и космических технологий</p><p>ул. Политехническая, д. 29, Санкт-Петербург, 195251</p></bio><bio xml:lang="en"><p>Sergey B. Makarov, Dr Sci. (Eng.) (1991), Professor (1994) of the Higher school of applied physics and space technologies</p><p> 29, Polytechnicheskaya St., St Petersburg 195251</p><p> </p></bio><email xlink:type="simple">makarov@cee.spbstu.ru</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0003-3398-3616</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Завьялов</surname><given-names>С. В.</given-names></name><name name-style="western" xml:lang="en"><surname>Zavjalov</surname><given-names>S. V.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Завьялов Сергей Викторович – кандидат технических наук (2015), доцент (2020) Высшей школы прикладной физики и космических технологий</p><p>ул. Политехническая, д. 29, Санкт-Петербург, 195251</p></bio><bio xml:lang="en"><p>Sergey V. Zavjalov, Cand. Sci. (Eng.) (2015), Associate Professor (2020) of the Higher school of applied physics and space technologies</p><p>29, Polytechnicheskaya St., St Petersburg 195251</p></bio><email xlink:type="simple">zavyalov_sv@spbstu.ru</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-3401-2718</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Овсянникова</surname><given-names>А. С.</given-names></name><name name-style="western" xml:lang="en"><surname>Ovsyannikova</surname><given-names>A. S.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Овсянникова Анна Сергеевна – аспирант Высшей школы прикладной физики и космических технологий</p><p>ул. Политехническая, д. 29, Санкт-Петербург, 195251</p></bio><bio xml:lang="en"><p>Anna S. Ovsyannikova, Postgraduate student of the Higher school of applied physics and space technologies</p><p>29, Polytechnicheskaya St., St Petersburg 195251</p></bio><email xlink:type="simple">ovsyannikova_as@spbstu.ru</email><xref ref-type="aff" rid="aff-1"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru"><institution>Санкт-Петербургский политехнический университет Петра Великого</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Peter the Great St. Petersburg Polytechnic University</institution><country>Russian Federation</country></aff></aff-alternatives><pub-date pub-type="collection"><year>2022</year></pub-date><pub-date pub-type="epub"><day>28</day><month>09</month><year>2022</year></pub-date><volume>25</volume><issue>4</issue><fpage>6</fpage><lpage>22</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Макаров С.Б., Завьялов С.В., Овсянникова А.С., 2022</copyright-statement><copyright-year>2022</copyright-year><copyright-holder xml:lang="ru">Макаров С.Б., Завьялов С.В., Овсянникова А.С.</copyright-holder><copyright-holder xml:lang="en">Makarov S.B., Zavjalov S.V., Ovsyannikova A.S.</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://re.eltech.ru/jour/article/view/658">https://re.eltech.ru/jour/article/view/658</self-uri><abstract><sec><title>Введение</title><p>Введение. Рост объемов передаваемой информации по каналам связи приводит к их существенной перегруженности. Практически все используемые традиционные методы повышения скорости передачи данных в заданных полосах частот исчерпаны. В этой связи представляет интерес использование новых подходов, направленных на повышение спектральной эффективности радиотехнических и телекоммуникационных систем путем применения оптимальных сигналов, позволяющих задействовать резервы пропускной способности каналов передачи, которые дает теория Шеннона.</p></sec><sec><title>Цель работы</title><p>Цель работы. Повышение спектральной эффективности систем передачи цифровых сообщений путем применения сигналов с компактным спектром и увеличения объема канального алфавита при минимизации энергетических потерь.</p></sec><sec><title>Материалы и методы</title><p>Материалы и методы. При поиске оптимальных сигналов используется математический аппарат теории связи и функционального анализа, а также методы вариационного исчисления. Оценка помехоустойчивости приема полученных оптимальных сигналов при передаче в канале с аддитивным белым гауссовским шумом выполнена в среде MatLab.</p></sec><sec><title>Результаты</title><p>Результаты. Установлено, что в канале с аддитивным белым гауссовским шумом оптимальные сигналы при размере сигнального созвездия 64 в случае квадратурной амплитудно-фазовой модуляции обеспечивают энергетический выигрыш более 1 дБ относительно сигналов, которые получаются путем узкополосной фильтрации в условиях неконтролируемой межсимвольной интерференции. Показано, что оптимальные сигналы позволяют получить энергетический выигрыш 4.9 дБ по отношению к сигналам, построенным на основе узкополосной фильтрации, при фиксированной спектральной эффективности 7 (бит/с)/Гц.</p></sec><sec><title>Заключение</title><p>Заключение. Предложен метод повышения спектральной эффективности квадратурных сигналов с амплитудно-фазовой модуляцией, основанный на применении оптимальных форм импульсов, полученных в ходе решения оптимизационной задачи. Приведена процедура решения оптимизационной задачи по критерию минимизации внеполосных излучений при наличии ограничения на помехоустойчивость приема в случае амплитудно-фазовой модуляции. Выполнено сравнение энергетической и спектральной эффективности, обеспечиваемой сигналами с оптимальными формами импульсов и сигналами, построенными на основе узкополосной фильтрации.</p></sec></abstract><trans-abstract xml:lang="en"><sec><title>Introduction</title><p>Introduction. The growth in the volume of information transmitted through communication channels leads to their significant congestion. Almost all methods conventionally used to increase the data transfer rate in given frequency bands have been exhausted. In this regard, it is of interest to use new approaches aimed at improving the spectral efficiency of radio engineering and telecommunication systems by applying optimal signals that make it possible to use the bandwidth reserves of transmission channels given by Shannon's theory.</p></sec><sec><title>Aim</title><p>Aim. Improvement of the spectral efficiency of digital messaging systems by using signals with a compact spectrum and increased volume of the channel alphabet at the same time as minimizing energy losses.</p></sec><sec><title>Materials and methods</title><p>Materials and methods. When searching for optimal signals, the mathematical apparatus of communication theory and functional analysis, as well as the methods of calculus of variations, were used. The evaluation of bit error rate performance of the obtained optimal signals transmitted in a channel with additive white Gaussian noise was performed in the MatLab environment. Results. It was established that, in a channel with additive white Gaussian noise, optimal signals with a signal constellation size of 64 in the case of quadrature amplitude-phase modulation provide an energy gain of more than 1 dB relative to signals obtained by narrowband filtering under the conditions of uncontrolled intersymbol interference. Optimal signals were shown to provide for an energy gain of 4.9 dB with respect to signals based on narrow-band filtering at a fixed spectral efficiency of 7 (bit/s)/Hz.</p></sec><sec><title>Conclusion</title><p>Conclusion. The paper proposes a method for improving the spectral efficiency of quadrature signals with amplitudephase modulation, based on the use of optimal pulse shapes obtained as a result of solving an optimization problem. The optimization problem was solved according to the criterion of minimizing out-of-band emissions with the constraint on bit error rate performance in case of amplitude-phase modulation. The energy and spectral efficiency of signals with optimal pulse shapes and signals based on narrow-band filtering were compared.</p></sec></trans-abstract><kwd-group xml:lang="ru"><kwd>оптимизационная задача</kwd><kwd>внеполосные излучения</kwd><kwd>спектральная эффективность</kwd><kwd>энергетическая эффективность</kwd><kwd>граница Шеннона</kwd><kwd>RRC</kwd></kwd-group><kwd-group xml:lang="en"><kwd>optimization problem</kwd><kwd>out-of-band emissions</kwd><kwd>spectral efficiency</kwd><kwd>energy efficiency</kwd><kwd>Shannon limit</kwd><kwd>RRC</kwd></kwd-group><funding-group><funding-statement xml:lang="ru">Исследования выполнены при финансовой поддержке Минобрнауки России в рамках соглашения о предоставлении гранта в форме субсидий из федерального бюджета на осуществление государственной поддержки создания и развития научных центров мирового уровня, выполняющих исследования и разработки по приоритетам научно-технологического развития от 20 апреля 2022 года № 075-15-2022-311</funding-statement><funding-statement xml:lang="en">The research was carried out with the financial support of the Russian Ministry of Education and Science within the framework of the grant agreement in the form of subsidies from the federal budget for state support for the creation and development of world-class research centers that carry out research and development on the priorities of scientific and technological development dated April 20, 2022 No. 075-15 -2022-311</funding-statement></funding-group></article-meta></front><back><ref-list><title>References</title><ref id="cit1"><label>1</label><citation-alternatives><mixed-citation xml:lang="ru">ETSI EN 302 307-1 v1.4.1 (2014-11): Digital Video Broadcasting (DVB); Second generation framing structure, channel coding and modulation systems for Broadcasting, Interactive Services, News Gathering and other broadband satellite applications. 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