Using of Residual Number System as a Mathematical Basis for Software Defined Radio

Вступ. У традицiйному виглядi, програмно-визначена радiосистема (Software Defined Radio, SDR) являє собою обчислювальне ядро, обладнане приймально-передавальними блоками. З метою прискорення обчислювальних операцiй у системах SDR, пропонується у якостi математичної основи застосування системи залишкових класiв. Результати попереднiх дослiджень, що проводились рiзними групами вчених з метою пошукiв шляхiв пiдвищення продуктивностi обчислювальних засобiв, методiв органiзацiї ефективної системи виявлення та виправлення помилок, а також побудови надiйних обчислювальних комплексiв, дають можливiсть стверджувати, що в межах позицiйних систем числення не можна очiкувати принципових зрушень в даних напрямках без суттєвого збiльшення робочих частот i ускладнення апаратної частини. Перевагою пропонованого методу є те, що програмна радiосистема може складатися з декiлькох ПЛIС i обслуговувати декiлька незалежних радiоканалiв, а перепрограмування властивостей дозволяє змiнювати число i складовi процесу обробки повiдомлень в залежностi вiд поточних умов роботи. Метод дослiдження. В роздiлi проаналiзовано паралельнiсть арифметичнi операцiї у системi залишкових класiв. Цi операцiї називаються модульними, оскiльки для обробки числових значень використовують невеликi залишки дiлення на певний набiр модулiв, а для додавання i множення потрiбно лише один тактовий цикл роботи обчислювальної системи. Для перетворення чисел iз двiйкової системи у RNS використовується алгоритм, заснований на застосуваннi китайської теореми про залишки. Проте такi операцiї, як подiл, порiвняння двох чисел i виявлення знака, є складними i ресурсо-затратними в RNS. Для цих проблемних операцiй було запропоновано кiлька рiшень. Вони полягають у вiдсутностi процесу перетвореннi залишку в бiнарну систему (зворотне перетворення) шляхом застосування цифро-аналогових перетворювачiв у RNS. З iншого боку, вибiр правильного набору модулiв є ще одним важливим питанням для побудови ефективного RNS з достатнiм динамiчним дiапазоном. Результати та аналiз. Пiдводячи пiдсумки деяких результатiв, можна зазначити, що система класiв залишкiв дозволяє значно полiпшити параметри обчислювача у SDR, а особливо у функцiональному блоковi Direct Digital Synthesizers (DDS) у порiвняннi з обчислювачем, побудованим на тiй же фiзичнiй i технологiчнiй основi, але в позицiйнiй обчислювальнiй системi, а також отримання нових бiльш прогресивних конструктивних i структурних рiшень. Експериментальнi результати показують, що представленi методи дають значнi переваги для цифрових фiльтрiв у SDR, якi характеризуються високим динамiчним дiапазоном i мають велику кiлькiстю ланок, особливо коли повнi перемножувачi не доступнi у цiльовiй архiтектурi FPGA, або коли цi перемножувачi повиннi використовуватися для рiзних цiлей. Висновки. Таким чином, запропонована система вносить явнi переваги перед iснуючими системами i показує переваги продуктивностi обчислювальних операцiй i може бути використана для побудови сучасних систем зв’язку. Запропонована архiтектура зменшує розмiри конвеєру суматорiв i перемножувачiв, що є дуже важливим фактором при розробцi високошвидкiсних SDR.Introduction. In the classic view, program-defined radio system (Software Defined Radio, SDR) is a central processor, equipped with receiving and transmitting units. In order to speed up computational operations in SDR systems it is proposed to use the system of residual classes as a mathematical basis. The results of research conducted by various groups of scientists in order to find ways to improve the performance of computing tools, methods of organizing an effective system for detecting and correcting errors, as well as building reliable computer systems, make it possible to assert that, within the limits of positional number systems, no fundamental changes can be expected in these areas without a significant increase in operating frequencies and hardware complications. The advantage of this method is that a software radio system can consist of several FPGAs and serve several independent radio channels, and reprogramming the properties allows you to change the number and components of message processors depending on current operating conditions. Research method. The equations in this section show the parallel nature of the RNS, free from bit transfers. These operations are called modular, because for it takes only one clock cycle to process the numerical values. To convert numbers from the binary position number system to RNS we use an algorithm based on the application of a distributed arithmetic. However, operations such as division, comparison of two numbers, and the detection of a sign are laborious and expensive in RNS Several decisions were proposed for these problem operations. They consist in the absence of the process of converting a residue into a binary system (reverse transformation) by using digital-to-analog converters in RNS. On the other hand, choosing the right set of modules is another important issue for building an effective RNS with a sufficient dynamic range. Results and analysis. Summing up some results, it can be noted that the system of residual classes allows to significantly improve the parameters of a computer in SDR especially in functional block a Direct Digital Synthesizers (DDS) in comparison with a computer built on the same physical and technological basis, but in a positional system calculation, and also to receive new more progressive constructive and structural solutions. The experimental results shows that the presented techniques offer interesting advantages for FIR filters characterized by high dynamic range and high number of taps especially when full custom multipliers are not available in the target FPGA architecture or when they must to be used for different purposes. Conclusion. Thus, the proposed system introduces clear advantages over existing systems and shows performance advantages and can be used to build modern communication systems. The proposed architecture reduces the size of the pipeline adders and multipliers which is a very important factor in the design SDR for fast work.В статье рассмотрены принципы построения и функционирования систем, определенных программным обеспечением (Software Defned Radio, SDR). С целью ускорения вычислительных операций в системах SDR предлагается применение системы остаточных классов в качестве математической основы построения систем. Преимуществом приведенного метода является то, что программная радиосистема может состоять из нескольких ПЛИС и обслуживать несколько независимых радиоканалов, а перепрограммирование свойств позволяет изменять число и составляющие процессоры сообщений в зависимости от текущих условий роботы. Приведены проблемы формирования выходного сигнала. Описаны особенности внедрения операций прямого и обратного преобразований с позиционных на непозиционые системы исчисления. Рассмотрена структурная модель SDR с прямыми цифровыми синтезаторами частоты, ЦАП, АЦП, цифровыми фильтрами в системе остаточных классов. Рассмотрены методы преобразования системы остаточных класов в аналоговый сигнал. Рассматриваются проблемы эффективного использования площади кристалла для SDR и уменьшения задержек в формировании выходного сигнала. Полученные результаты показывают широкие возможности применения программно определенной радиосистемы в системе остаточных классов

Transmission Of Control Information In 5G Broadband Telecommunication Systems

This article discusses the polar code is applied to the transmission of control information in broadband telecommunications systems. Channel coding contains a set of procedures for error detection, error correction, rate matching, bit interleaving and mapping of information to physical control channels or transport layer. The article explores a downlink model with polar coding and multi-position digital phase modulation. This model presents the results of Bit Error Rate (BER) for coding scheme with different code rates. The structural scheme of the decision model on the modulation mode of the digital communication system is analysed in the paper. Dependencies of BER on the effective rate of the polar code with different types of modulation are explored. The modulation mode selection adaptive algorithm for code rate R=0.5 is developed on the basis of the obtained dependencies. The use of signal-code construction based on the polar code can increase the efficiency of the communication system

Organizational model of the congress and exhibition cluster in the field of business travel

The relevance of the analyzed issue is caused by the growth of the international trade in the intensity of business travel services, including in the field of the congress and exhibition business, which necessitates the formation of the effective management model of business travel services at the destination level. The purpose of the article is to substantiate the formation algorithm of the cluster development strategy of tourism and the development of organizational functioning models of the congress and exhibition cluster in the destination. The leading approach to the study of this issue is the method of modeling, which allowed considering the practice of clusters functioning as a sequence of stages of its formation and development, taking into account the resource potential of destinations. Results: the article presents a stepwise algorithm for creating the congress and exhibition cluster in the destination and proves the fundamental organizational model for its functioning in the business tourism market; isolates and systematized criteria and indicators for assessing the contribution of participants of the tourism cluster in the destination development. The contents of this article may be useful for researchers, interested in the use of the cluster approach in the services sector, as well as to regional authorities, responsible for the development of tourism. © 2016 Karpova et al

The influenza epidemic in Russia during the 2014–2015 season

The goal of this study was to compare the data on the intensity of the influenza A(H3N2) and B epidemic (especially the death toll) in the 2014–2015 season with the previous epidemic of the 2013-2014 season. The data on weekly morbidity, hospitalization, deaths from influenza, and acute respiratory diseases in different age groups of inhabitants of 59 cities located in 7 Federal districts of the Russian Federation were collected using the database of the Research Institute of Influenza.Analysis of this data showed that the influenza epidemic in 2014-2015 began earlier (in December) compared to the epidemic of 2013-2014, and spread mainly from Europe through Russia to the East. The intensity of the epidemic of 2014-2015 was higher compared to the previous one. The epidemic was more prevalent by regions and cities and a wider engagement of different age groups (except children up to 2 years of age) was observed. At the peak of the epidemic, the morbidity level was higher, the average duration of the epidemic was longer, and the number of patients among cities’ inhabitants (especially among children 7-14 years of age and adults) was higher than in the previous season. The rates of hospitalization with influenza and acute respiratory viral infections (ARVI) among patients older than 65 years were also higher (1.4 times) as well as the frequency of hospitalization with a diagnosis of “influenza” (2.7 times) and the number of deaths from laboratory confirmed influenza (1.8 times).Although the influenza pandemic virus strain A(H1N1)pdm09 was not the main causative agent of the 2015 epidemic and was distributed sporadically it still remained the leading cause of deaths from influenza in the course of this epidemic (45.5% of all cases). The deaths associated with this strain were recorded only in the European part of Russian Federation.The goal of this study was to compare the data on the intensity of the influenza A(H3N2) and B epidemic (especially the death toll) in the 2014–2015 season with the previous epidemic of the 2013-2014 season. The data on weekly morbidity, hospitalization, deaths from influenza, and acute respiratory diseases in different age groups of inhabitants of 59 cities located in 7 Federal districts of the Russian Federation were collected using the database of the Research Institute of Influenza. Analysis of this data showed that the influenza epidemic in 2014-2015 began earlier (in December) compared to the epidemic of 2013-2014, and spread mainly from Europe through Russia to the East. The intensity of the epidemic of 2014-2015 was higher compared to the previous one. The epidemic was more prevalent by regions and cities and a wider engagement of different age groups (except children up to 2 years of age) was observed. At the peak of the epidemic, the morbidity level was higher, the average duration of the epidemic was longer, and the number of patients among cities’ inhabitants (especially among children 7-14 years of age and adults) was higher than in the previous season. The rates of hospitalization with influenza and acute respiratory viral infections (ARVI) among patients older than 65 years were also higher (1.4 times) as well as the frequency of hospitalization with a diagnosis of “influenza” (2.7 times) and the number of deaths from laboratory confirmed influenza (1.8 times). Although the influenza pandemic virus strain A(H1N1)pdm09 was not the main causative agent of the 2015 epidemic and was distributed sporadically it still remained the leading cause of deaths from influenza in the course of this epidemic (45.5% of all cases). The deaths associated with this strain were recorded only in the European part of Russian Federation

Prerequisites for setting up management system in municipal retail trade

The relevance of the problem is determined by the number of complex problems that exist in present Samara municipal retail trade system, which is manifested in the lack of regulation, a glut of sales area, poorly developed infrastructure. The purpose of this article is to form a quantitative base for determining the municipal needs in the floor space. Leading method to study this problem is the method of empirical observations and mathematical modeling. The study results: the article contains the analysis of sales area availability on the example in the urban district and presents a quantitative method to determine predictive values for retail trade turnover. Practical significance: the paper is aimed to develop managerial decisions in the sphere of municipal trade regulation. © 2016 Suraeva et al

Coветское дирижаблестроение в 1935-1937 гг

The article treats the history of the Soviet airship production in the period of 1935-1937, which became a turning point in its development. The new archive materials became public in the scientific community for the first time.Рассматривается история советского дирижаблестроения в период 1935-1937 гг., ставший переломным в его развитии. Впервые в научный оборот вводятся новые архивные материалы

ABOUT THE CIRCULATION OF INFLUENZA VIRUS A AND THE DEATHS OF BIRDS IN SOUTH OF CENTRAL SIBERIA

It was studied the long-term dynamics of influenza A viruses circulation in the Southern Central Siberia. Also, we studied of birds population dynamic as the main carriers of viral infection, as well as spatial and temporal distribution of positive samples containing specific antibody to influenza viruses subtypes H5 and. H7 and. genomic RNA of these subtypes. It was considered the cases of mortality wild. and. synanthropic birds in the region. It was shown a correlation between the identified centers of the virus influenza, the deaths of birds and. human disease with significant excess seasonal epidemic threshold, including a subtype Н1NЫЦ

Hypoxia-induced factor-1α and markers of inflammation in patients with ischemic stroke

Ischemic stroke (IS) occurs as a result of local disturbance of hemocirculation and hypoxia in the brain tissue. Hypoxia-inducible factor-1α (HIF-1α), which is involved in the regulation of tissue oxygen levels, plays an important role in the pathophysiology of stroke, including neuronal survival, neuroinflammation, angiogenesis, glucose metabolism, blood-brain barrier permeability, and is important in IS outcomes. The purpose of the study was to determine the relationship between blood levels of HIF-1α and the degree of neurological deficit in the acute period of IS and the outcome of the disease. We examined 58 people with IS aged 73 (67-81) years. Patients were divided into two groups – discharged and dead. The severity of stroke (NIHSS), neurological deficit, comorbidity index, blood levels of HIF-1α, p53 protein, interleukin-6, cystatin C, CRP, creatinine, hematological parameters were determined at admission, on days 3 and 10 of the disease. At admission the blood levels of HIF-1α was lower than in the comparison group and remained reduced until the 10th day. On day 10 the association of HIF-1α with neurological deficit, comorbidity index and disease outcome was determined. We observed a feedback of HIF-1α with the content of erythrocytes, hemoglobin and hematocrit, which can be regarded as a reflection of the hemic component of mixed hypoxia. In dead patients, an increased blood level of cystatin C was detected, which was associated with HIF-1α concentrations. In all periods of observation of IS, a correlation between cystatin C and creatinine and CRP levels was noted. These results may indicate dysfunction of endotheliocytes, inflammation associated with hypoxia in IS. The prognostic significance of the blood level of HIF-1α on the 10th day for the outcome of IS was AUC = 0.900. Blood levels of HIF-1α in the acute period was associated with the severity of IS and the outcome of the disease

NEW DIRECTIONS FOR IMPROVEMENT OF BREAST CANCER SCREENING

Objective: to improve breast cancer diagnosis using an independent mammographic teleassessment by two radiologists. Material and methods. The results of a dual independent assessment of 3440 X-ray mammographic examinations were analyzed. The first assessment was made by a radiologist from a therapeutic-and-prophylactic establishment who had less than one year of practical experience in a mammography screening room. The second assessment was carried out by a radiologist with more than 5 years of experience from a specialized cancer institution. Results. According to the developed specialized interpretation software, recommendations and statistics for mammographic breast cancer screening, the investigators identified a group of 31 women who were recommended to be additionally examined at an oncology dispensary to verify the diagnosis of breast cancer. Eight of 17 (47%) women with morphologically confirmed cancers after dual assessments of X-ray mammographs were called again and referred to the oncology dispensary. Conclusion. Dual independent assessment of X-ray mammographs improved the diagnosis of BC with a maximum size of 1.5 cm or less, as well as that of malignant tumors manifesting as microcalcifications or imitating a benign process