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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">10.32603/1993-8985-2020-23-4-25-37</article-id><article-id custom-type="elpub" pub-id-type="custom">radioelectronics-451</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>СИСТЕМЫ, СЕТИ И УСТРОЙСТВА ТЕЛЕКОММУНИКАЦИЙ</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="en"><subject>TELECOMMUNICATION SYSTEMS, NETWORKS AND DEVICES</subject></subj-group></article-categories><title-group><article-title>Спектральная эффективность беспроводной релейной сети в частотно-неселективном канале</article-title><trans-title-group xml:lang="en"><trans-title>Spectral Efficiency of Wireless Relay Network in Frequency Non-Selective Channel</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-5707-0806</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Маврычев</surname><given-names>Е. А.</given-names></name><name name-style="western" xml:lang="en"><surname>Mavrychev</surname><given-names>E. A.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Маврычев Евгений Александрович – кандидат технических наук (2003), доцент (2012) кафедры информационных радиосистем, ул. Минина, д. 24, Н. Новгород, 603950, Россия</p></bio><bio xml:lang="en"><p>Evgeny A. Mavrychev, Cand. Sci. (Eng.) (2003), Associate Professor (2012) on the Department of Information Radio Systems, 24, Minin St., Nizhny Novgorod 603950, Russia</p></bio><email xlink:type="simple">mavrychev.eugene@mail.ru</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Приблудова</surname><given-names>Е. Н.</given-names></name><name name-style="western" xml:lang="en"><surname>Pribludova</surname><given-names>E. N.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Приблудова Елена Николаевна – кандидат технических наук (2000), доцент (2002) кафедры информационных радиосистем, ул. Минина, д. 24, Н. Новгород, 603950, Россия</p></bio><bio xml:lang="en"><p>Elena N. Pribludova, Cand. Sci. (Eng.) (2000), Associate Professor (2002) on the Department of Information Radio Systems, 24, Minin St., Nizhny Novgorod 603950, Russia</p></bio><email xlink:type="simple">pribludova@nntu.ru</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Сидоров</surname><given-names>С. Б.</given-names></name><name name-style="western" xml:lang="en"><surname>Sidorov</surname><given-names>S. B.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Сидоров Сергей Борисович – кандидат технических наук (2000), доцент (2002) кафедры информационных радиосистем, ул. Минина, д. 24, Н. Новгород, 603950, Россия</p></bio><bio xml:lang="en"><p>Sergey B. Sidorov, Cand. Sci. (Eng.) (2000), Associate Professor (2002) on the Department of Information Radio Systems, 24, Minin St., Nizhny Novgorod 603950, Russia</p></bio><email xlink:type="simple">sidorov@nntu.ru</email><xref ref-type="aff" rid="aff-1"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru"><institution>Нижегородский государственный технический университет им. Р. Е. Алексеева</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Nizhny Novgorod State Technical University n. a. R. E. Alekseev</institution><country>Russian Federation</country></aff></aff-alternatives><pub-date pub-type="collection"><year>2020</year></pub-date><pub-date pub-type="epub"><day>07</day><month>10</month><year>2020</year></pub-date><volume>23</volume><issue>4</issue><fpage>25</fpage><lpage>37</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Маврычев Е.А., Приблудова Е.Н., Сидоров С.Б., 2020</copyright-statement><copyright-year>2020</copyright-year><copyright-holder xml:lang="ru">Маврычев Е.А., Приблудова Е.Н., Сидоров С.Б.</copyright-holder><copyright-holder xml:lang="en">Mavrychev E.A., Pribludova E.N., Sidorov S.B.</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/451">https://re.eltech.ru/jour/article/view/451</self-uri><abstract><sec><title>Введение</title><p>Введение. Рассмотрена беспроводная система передачи данных, построенная на основе релейной сети, в которой связь между источником и приемником осуществляется через сеть релейных станций. Релейные станции работают по протоколу "усиление и передача", при котором каждая станция выполняет прием сигнала, усиление, поворот фазы и передачу на станцию-приемник. В результате возникает задача оптимизации мощностей и фазовых сдвигов, излучаемых релейными узлами, т. е. комплексных коэффициентов передачи этих узлов. Комплексные весовые коэффициенты релейных узлов оптимизируются таким образом, чтобы обеспечить максимальное отношение сигнал/шум в приемнике, при этом накладываются ограничения на мощности, излучаемые релейными узлами. В настоящей статье рассмотрена оптимизация пространственной обработки сигналов при наличии различной априорной информации о состоянии канала.</p></sec><sec><title>Цель работы</title><p>Цель работы. Анализ спектральной эффективности беспроводной релейной сети в рэлеевском канале с оптимальной пространственной обработкой при наличии априорной информации двух видов: о мгновенном состоянии канала и знании статистик второго порядка.</p></sec><sec><title>Материалы и методы</title><p>Материалы и методы. Оптимизация пространственной обработки в релейной сети основана на методах статической теории и теории оптимизации с использованием аппарата линейной алгебры и численного решения оптимизационных задач. Характеристики релейной сети анализируются с помощью математического моделирования на основе метода Монте-Карло. Статистическое моделирование выполняется в среде MatLab с использованием стандартных средств, а также пакета CVX для численного решения выпуклых оптимизационных задач.</p></sec><sec><title>Результаты</title><p>Результаты. Представлены оптимальные решения для пространственной обработки сигналов релейной сети, основанные на критерии максимума отношения сигнал/шум при ограничении суммарной мощности сети или индивидуальных мощностей узлов сети. Проведено статистическое моделирование, получены спектральные эффективности релейной сети при наличии различного вида априорной информации о канале распространения сигнала и различных параметров канала. Получены зависимости средней пропускной способности для случайного рэлеевского канала от мощности источника и бюджета мощности на релейных узлах, а также статистических параметров канала, а именно коэффициентов, характеризующих соотношение между случайной и детерминированной составляющими канала.</p></sec><sec><title>Заключение</title><p>Заключение. Полученные результаты имеют практическое применение. Так использование знания статистик второго порядка возможно в релейных сетях, в которых обеспечивается условие прямой видимости с малым уровнем фона от местных предметов. В условиях городской застройки, при которых возникают затенения и многолучевое распространение сигналов, возможно использование только подхода, основанного на знании мгновенного состояния канала.</p></sec></abstract><trans-abstract xml:lang="en"><sec><title>Introduction</title><p>Introduction. A wireless communication system based on a relay network where a link between a source and a destination is carried out through a network of relay nodes have been considered. Relay networks operate according with amplifier-and-forward protocol where each relay node performs reception, amplifying, phase shifting and retranslation of a signal to the destination node. As a result a task of powers and phases optimization in the relay nodes (i.e. the complex weighted coefficients optimization) becomes actual. Complex weighted coefficients of the relay nodes are optimized in such a way as to ensure the maximum signal to noise ratio at the receiver while limiting a power emitted by the relay nodes. In the paper, optimization of spatial processing with different a priori channel state information (i.e. instantaneous channel state information and the second order statistics) have been considered.</p></sec><sec><title>Aim</title><p>Aim. Spectral efficiency analysis of a relay network in a multipath channel where the relay network was optimized by using of two types a priori information: an instantaneous channel state information and second order statistics.</p></sec><sec><title>Materials and methods</title><p>Materials and methods. Optimization of spatial signal processing in the relay network was based on methods of statistical theory and optimization using analytics of linear algebra and methods of mathematical programming. Performances of the relay network were analyzed using Monte Carlo simulation. The simulation was performed in MATLAB program environment using CVX toolbox for solving convex optimization task.</p></sec><sec><title>Results</title><p>Results. In the paper optimal solutions for spatial signal processing in the relay network were presented. The solutions were based on maximum of signal to noise ratio while limiting total relay power and individual power of relay nodes. Monte Carlo simulation was performed to provide performances of the relay network for different types of channel state information and channel parameters. Mean capacities versus mean source power, a budget of relay nodes power and a ratio between random and deterministic power of the channel were gained for the Rayleigh model of multipath channel.</p></sec><sec><title>Conclusions</title><p>Conclusions. The results have a practical application. Thus, the use of the second order statistics is possible in relay networks when direct visibility with a low level of background from local objects is provided. In urban areas, where shading and multipath propagation of signals occur, it is possible to use only an approach based on the knowledge of channel instantaneous state.</p></sec></trans-abstract><kwd-group xml:lang="ru"><kwd>релейная сеть</kwd><kwd>пространственная обработка сигналов</kwd><kwd>пропускная способность</kwd><kwd>много-лучевой канал</kwd><kwd>критерий максимума отношения сигнал/шум</kwd></kwd-group><kwd-group xml:lang="en"><kwd>relay network</kwd><kwd>spatial signal processing</kwd><kwd>capacity</kwd><kwd>multipath channel</kwd><kwd>criterion on maximum of signal-to-noise ratio</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">Telatar I. E. Capacity of Multi-Antenna Gaussian Channels // Eur. Trans. 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