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1
Fedosov, Valentin, Andrey Legin e Anna Lomakina. "Adaptive algorithm based on antenna arrays for radio communication systems". Serbian Journal of Electrical Engineering 14, n. 3 (2017): 301–12. http://dx.doi.org/10.2298/sjee1703301f.
Testo completoAbstract (sommario):
Trends in the modern world increasingly lead to the growing popularity of wireless technologies. This is possible due to the rapid development of mobile communications, the Internet gaining high popularity, using wireless networks at enterprises, offices, buildings, etc. It requires advanced network technologies with high throughput capacity to meet the needs of users. To date, a popular destination is the development of spatial signal processing techniques allowing to increase spatial bandwidth of communication channels. The most popular method is spatial coding MIMO to increase data transmission speed which is carried out due to several spatial streams emitted by several antennas. Another advantage of this technology is the bandwidth increase to be achieved without expanding the specified frequency range. Spatial coding methods are even more attractive due to a limited frequency resource. Currently, there is an increasing use of wireless communications (for example, WiFi and WiMAX) in information transmission networks. One of the main problems of evolving wireless systems is the need to increase bandwidth and improve the quality of service (reducing the error probability). Bandwidth can be increased by expanding the bandwidth or increasing the radiated power. Nevertheless, the application of these methods has some drawbacks, due to the requirements of biological protection and electromagnetic compatibility, the increase of power and the expansion of the frequency band is limited. This problem is especially relevant in mobile (cellular) communication systems and wireless networks operating in difficult signal propagation conditions. One of the most effective ways to solve this problem is to use adaptive antenna arrays with weakly correlated antenna elements. Communication systems using such antennas are called MIMO systems (Multiple Input Multiple Output multiple input - multiple outputs). At the moment, existing MIMO-idea implementations do not always noticeably accelerate traffic at short distances from the access point, but, they are very effective at long distances. The MIMO principle allows reducing the number of errors in radio data interchange (BER) without reducing the transmission rate under conditions of multiple signal re-reflections. The work aims at developing an adaptive space-time signal algorithm for a wireless data transmission system designed to improve the efficiency of this system, as well as to study the efficiency of the algorithm to minimizing the error bit probability and maximizing the channel capacity.
2
Olberg, P. "Multimedia Sensor Networks Based on Ultra-wideband Chaotic Radio Pulses". Bulletin of Science and Practice 7, n. 2 (15 febbraio 2021): 220–26. http://dx.doi.org/10.33619/2414-2948/63/21.
Testo completoAbstract (sommario):
The fast direction in information and communication systems of the wireless sensor network is discussed. Special attention was paid to ultra-wideband wireless sensor networks, which use chaotic radio pulses as information carriers for communication between sensor nodes. The creation of such systems became possible after many years of research on the creation and management of chaos in electronic systems. The requirements for transceivers for transmitting multimedia data in wireless sensor networks and the characteristics of existing systems are considered. The prospects of using ultra-wideband wireless systems based on direct chaotic data transmission in multimedia sensor networks are analyzed.
3
Kumar, A. Narendra. "Low Error Rate Data Transmission in Cognitive Radio Networks". JOURNAL OF ADVANCES IN CHEMISTRY 13, n. 10 (4 marzo 2017): 5899–904. http://dx.doi.org/10.24297/jac.v13i10.5832.
Testo completoAbstract (sommario):
Cognitive Radio (CR) has become a hopeful technology to enhance the spectrum utilization through spectrum sharing between licensed user (primary user) and unlicensed user (secondary user). An vital rule mandated for the development of such frameworks are to develop solutions that don’t require any changes to the existing primary user (PU) infrastructure. An Orthogonal Frequency Division Multiplexing (OFDM) is typically worn advancements in present wireless communication systems which has the possibility of fulfilling the demand for cognitive radios intrinsically or with slight changes. In this paper, Space time block codes is used. The various antennas used on both ends for trustworthy data broadcast and interference nulling schemes. These codes can accomplish full broadcast diversification determined via the number of broadcast antennas. The MIMO is worn for enhancing the power of a wireless link, to determine the issue for lower BER and achieve a superior performance.
4
Riurean, Simona. "Design and Evaluation of Visible Light Wireless Data Communication Models". Journal of Digital Science 2, n. 2 (29 dicembre 2020): 3–13. http://dx.doi.org/10.33847/2686-8296.2.2_1.
Testo completoAbstract (sommario):
The technologies based on the radio frequency used for wireless transmission indoor are more congested than ever these days, therefore several wireless communication alternatives are intensively searched. Some most promising technologies are based on the optical part of the electromagnetic spectrum. The benefits and drawbacks in optical wireless data communication models design are presented in this work. The key characteristics of the VLC systems are briefly discussed, as well. Some models developed for wireless data transfer in visible light communication and infrared are presented, and their operation related to the data rate and the length of the optical link, are briefly compared.
5
Huening, Felix, Holger Heuermann, Franz-Josef Wache e Rami Audisho Jajo. "A new wireless sensor interface using dual-mode radio". Journal of Sensors and Sensor Systems 7, n. 2 (21 settembre 2018): 507–15. http://dx.doi.org/10.5194/jsss-7-507-2018.
Testo completoAbstract (sommario):
Abstract. The integration of sensors is one of the major tasks in embedded, control and “internet of things” (IoT) applications. For the integration mainly digital interfaces are used, starting from rather simple pulse-width modulation (PWM) interface to more complex interfaces like CAN (Controller Area Network). Even though these interfaces are tethered by definition, a wireless realization is highly welcome in many applications to reduce cable and connector cost, increase the flexibility and realize new emerging applications like wireless control systems. Currently used wireless solutions like Bluetooth, WirelessHART or IO-Link Wireless use dedicated communication standards and corresponding higher protocol layers to realize the wireless communication. Due to the complexity of the communication and the protocol handling, additional latency and jitter are introduced to the data communication that can meet the requirements for many applications. Even though tunnelling of other bus data like CAN data is generally also possible the latency and jitter prevent the tunnelling from being transparent for the bus system. Therefore a new basic technology based on dual-mode radio is used to realize a wireless communication on the physical layer only, enabling a reliable and real-time data transfer. As this system operates on the physical layer it is independent of any higher layers of the OSI (open systems interconnection) model. Hence it can be used for several different communication systems to replace the tethered physical layer. A prototype is developed and tested for real-time wireless PWM, SENT (single-edge nibble transmission) and CAN data transfer with very low latency and jitter.
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Brennan, Daniel, Bing Miao, Konstantin Vassilevski, Nicolas G. Wright e Alton B. Horsfall. "Amplitude Shift Keyed Radio Communications for Hostile Environments". Materials Science Forum 645-648 (aprile 2010): 953–56. http://dx.doi.org/10.4028/www.scientific.net/msf.645-648.953.
Testo completoAbstract (sommario):
This work presents the amplitude modulation radio transmission system for communications in hostile environments. The commissioning of a high temperature oscillator and AM mixer system for the purpose of Amplitude Shift Keyed modulation is presented. While previous work has demonstrated oscillators in the Ultra High Frequency (UHF) band, these have been targeted at applications such as radar and mobile telephones. In this paper we have concentrated on the shortwave bands to maximize the range between a sensor unit and the receiver within wireless networks. The work demonstrates that simple communication systems are already possible for hostile environments and allow for simple sensor data to be wirelessly transmitted to safer working areas.
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Zhang, Zhenyu, Anas Chaaban e Lutz Lampe. "Physical layer security in light-fidelity systems". Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 378, n. 2169 (2 marzo 2020): 20190193. http://dx.doi.org/10.1098/rsta.2019.0193.
Testo completoAbstract (sommario):
Light-fidelity (LiFi) is a light-based wireless communication technology which can complement radio-frequency (RF) communication technologies for indoor applications. Although LiFi signals are spatially more contained than RF signals, the broadcasting nature of LiFi also makes it susceptible to eavesdropping. Therefore, it is important to secure the transmitted data against potential eavesdroppers. In this paper, an overview of the recent developments pertaining to LiFi physical layer security (PLS) is provided, and the main differences between LiFi PLS and RF PLS are explained. LiFi achievable secrecy rates and upper bounds are then investigated under practical channel models and transmission schemes. Beamforming and jamming, which received significant research attention recently as a means to achieve PLS in LiFi, are also investigated under indoor illumination constraints. Finally, future research directions of interest in LiFi PLS are identified and discussed. This article is part of the theme issue ‘Optical wireless communication’.
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Heslop, Liza, Andrew Howard, Juanita Fernando, Andrew Rothfield e Lyn Wallace. "Wireless communications in acute health-care". Journal of Telemedicine and Telecare 9, n. 4 (1 agosto 2003): 187–93. http://dx.doi.org/10.1258/135763303322225490.
Testo completoAbstract (sommario):
Before a particular form of wireless communication is implemented within a health-care institution, consideration should be given to the system's capacity for transmitting voice, data and video information, as well as its reliability and coverage. An important associated choice concerns the best combination of user devices that will enable secure and rapid transmission of data to clinical staff at the point of care. Several technologies are available. No new technology that is likely to become available over the next five years will address the two main concerns of health service organizations: the need for non-interference with sensitive equipment; and the need for immediate communication of urgent messages. We therefore believe that health industries with a mobile workforce will gain five to eight years of useful life from cordless telephone systems and that paging or other radio-based devices will remain an important mode of communication for at least the next five years, especially where emergency communication is concerned.
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Garlinska, Magdalena, Agnieszka Pregowska, Karol Masztalerz e Magdalena Osial. "From Mirrors to Free-Space Optical Communication—Historical Aspects in Data Transmission". Future Internet 12, n. 11 (22 ottobre 2020): 179. http://dx.doi.org/10.3390/fi12110179.
Testo completoAbstract (sommario):
Fast communication is of high importance. Recently, increased data demand and crowded radio frequency spectrum have become crucial issues. Free-Space Optical Communication (FSOC) has diametrically changed the way people exchange information. As an alternative to wire communication systems, it allows efficient voice, video, and data transmission using a medium like air. Due to its large bandwidth, FSOC can be used in various applications and has therefore become an important part of our everyday life. The main advantages of FSOC are a high speed, cost savings, compact structures, low power, energy efficiency, a maximal transfer capacity, and applicability. The rapid development of the high-speed connection technology allows one to reduce the repair downtime and gives the ability to quickly establish a backup network in an emergency. Unfortunately, FSOC is susceptible to disruption due to atmospheric conditions or direct sunlight. Here, we briefly discuss Free-Space Optical Communication from mirrors and optical telegraphs to modern wireless systems and outline the future development directions of optical communication.
10
Brandl, Martin, e Karlheinz Kellner. "Performance Evaluation of Power-Line Communication Systems for LIN-Bus Based Data Transmission". Electronics 10, n. 1 (4 gennaio 2021): 85. http://dx.doi.org/10.3390/electronics10010085.
Testo completoAbstract (sommario):
Powerline communication (PLC) is a versatile method that uses existing infrastructure such as power cables for data transmission. This makes PLC an alternative and cost-effective technology for the transmission of sensor and actuator data by making dual use of the power line and avoiding the need for other communication solutions; such as wireless radio frequency communication. A PLC modem using DSSS (direct sequence spread spectrum) for reliable LIN-bus based data transmission has been developed for automotive applications. Due to the almost complete system implementation in a low power microcontroller; the component cost could be radically reduced which is a necessary requirement for automotive applications. For performance evaluation the DSSS modem was compared to two commercial PLC systems. The DSSS and one of the commercial PLC systems were designed as a direct conversion receiver; the other commercial module uses a superheterodyne architecture. The performance of the systems was tested under the influence of narrowband interference and additive Gaussian noise added to the transmission channel. It was found that the performance of the DSSS modem against singleton interference is better than that of commercial PLC transceivers by at least the processing gain. The performance of the DSSS modem was at least 6 dB better than the other modules tested under the influence of the additive white Gaussian noise on the transmission channel at data rates of 19.2 kB/s.
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Ancans, G., A. Stafecka, V. Bobrovs, A. Ancans e J. Caiko. "Analysis of Characteristics and Requirements for 5G Mobile Communication Systems". Latvian Journal of Physics and Technical Sciences 54, n. 4 (1 agosto 2017): 69–78. http://dx.doi.org/10.1515/lpts-2017-0028.
Testo completoAbstract (sommario):
Abstract One of the main objectives of the fifth generation (5G) mobile communication systems, also known as IMT-2020, is to increase the current data rates up to several gigabits per second (Gbit/s) or even up to 10 Gbit/s and higher. One of the possibilities to consider is the use of higher frequencies in order to enlarge the available bandwidth. Wider bandwidth is necessary to achieve much higher data rates. It should be noted that wireless broadband transmission technologies require frequencies for their development. The main goal of the research is to investigate the characteristics and requirements of 5G mobile communication systems. The paper provides an insight into deployment scenario and radio wave propagation in frequencies above 24 GHz of IMT-2020.
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Bednarek, Marcin, e Dąbrowski Dąbrowski. "CONCEPT OF THE DATA TRANSMISSION SECURITY IN THE MOBILE DIAGNOSTIC SYSTEM / KONCEPCJA ZABEZPIECZENIA TRANSMISJI DANYCH W MOBILNYM SYSTEMIE DIAGNOSTYCZNYM". Journal of KONBiN 26, n. 1 (1 giugno 2013): 61–70. http://dx.doi.org/10.2478/jok-2013-0082.
Testo completoAbstract (sommario):
Abstract The concept of security data transmission in a mobile diagnostic system composed of the process stations (remote parts of the supervising and therapeutic system) and the operator station (local part of the supervising and therapeutic system) is presented. Process stations are connected to the operator station via radio modems. It allows the installation in mobile facilities. Communication between stations is realized via wireless access points. The examples of the application of the presented issues in mobile systems, as well as the potentially locations of the security risks of transmission are given. The possible options for secure communications are described. The assumptions of the concept of a secure communication in the diagnostic system are explained.
13
Nguyen, Minh Tuong, Viktor I. Nefedov, Igor V. Kozlovsky, Alexey V. Malafeev, Kirill A. Selenya e Natalia A. Mirolyubova. "Analysis of the Raman spectrum of high-power amplifiers of wireless communication systems". Russian Technological Journal 7, n. 6 (10 gennaio 2020): 96–105. http://dx.doi.org/10.32362/2500-316x-2019-7-6-96-105.
Testo completoAbstract (sommario):
At present, the transfer of information is an integral part of technologies that are actively developing in the framework of the process called the Fourth Industrial Revolution. In this, space-satellite, satellite and other mobile wireless communication systems play an increasingly important role. Almost all of them include multiple access, which means a method of common resource division of the communication channel between subscribers (each mobile station has the ability to use a satellite retransmitter or the base station of a mobile wireless communication system to transmit its signals regardless of the operation of another station). Multiple-access communication systems are used for digital radio and television broadcasting in high-speed communication lines, in wireless local area networks, for data transmission in the microwave range, and also for communication with various mobile partners. In the radio transmitting and receiving paths of communication systems with multiple access, multiple signals are used (the sum of the power of the subscriber signals) with very complex types of digital envelope modulation, so they use wide working bands. With an increase in the quality of information transmission in mobile wireless communication systems, there are special requirements for powerful amplification systems (PAS) of receiving-transmitting tracts, which must have high efficiency and high output power, required bandwidth, network capacity, and linearity of message transmission channels. To achieve maximum efficiency in the PAS, the operating point of its amplifying element should be near the saturation region, on the main nonlinearity of the transfer characteristic. When multiple signals are introduced simultaneously into the PAS, it generates unfiltered intermodulation harmonics (IH). Intermodulation harmonics are formed due to the nonlinearity of the amplitude characteristics and the unevenness of phase-amplitude characteristics and due to the need to work with the highest efficiency of the PAS, which requires a shift of the operating point to the saturation thresholds of their amplifying elements. This, in turn, causes the appearance of IH. Since the harmonic oscillations IH actually represent noise for neighboring communication channels and are not theoretically filtered, an equalizer (otherwise an optimizer) of characteristics, is needed to reduce the level of these interferences in the output (Raman) spectrum of the PAS.
14
Dan, Iulia, Guillaume Ducournau, Shintaro Hisatake, Pascal Szriftgiser, Ralf-Peter Braun e Ingmar Kallfass. "A superheterodyne 300 GHz wireless link for ultra-fast terahertz communication systems". International Journal of Microwave and Wireless Technologies 12, n. 7 (19 maggio 2020): 578–87. http://dx.doi.org/10.1017/s1759078720000495.
Testo completoAbstract (sommario):
A superheterodyne transmission scheme is adopted and analyzed in a 300 GHz wireless point-to-point link. This was realized using two different intermediate frequency (IF) systems. The first uses fast digital synthesis which provides an IF signal centered around a carrier frequency of 10 GHz. The second involves the usage of commercially available mixers, which work as direct up- and down-converters, to generate the IF input and output. The radio frequency components are based on millimeterwave monolithic integrated circuits at a center frequency of 300 GHz. Transmission experiments over distances up to 10 m are carried out. Data rates of up to 60 Gbps using the first IF option and up to 24 Gbps using the second IF option are achieved. Modulation formats up to 32QAM are successfully transmitted. The linearity of this link and of its components is analyzed in detail. Two local oscillators (LOs), a photonics-based source and a commercially available electronic source are employed and compared. This work validates the concept of superheterodyne architecture for integration in a beyond-5G network, supplying important guidelines that have to be taken into account in the design steps of a future wireless system.
15
Nguyen, Van Hoa, Minh Duc Thieu, Huy Nguyen e Yeong Min Jang. "Design and Implementation of the MIMO–COOK Scheme Using an Image Sensor for Long-Range Communication". Sensors 20, n. 8 (16 aprile 2020): 2258. http://dx.doi.org/10.3390/s20082258.
Testo completoAbstract (sommario):
Radio-frequency technologies are widely applied in many fields such as mobile systems, healthcare systems, television and radio broadcasting, and satellite communications. However, one major problem in wireless communication based on radio frequencies is its impact on human health. High frequencies adversely impact human health more than low frequencies if the signal power transgresses the permissible threshold. Therefore, researchers are investigating the use of visible light waves (instead of the radio-frequency band) for data transmission in three major areas: visible light communication, light fidelity, and optical camera communication. In this paper, we propose a scheme that upgrades the camera on–off keying (COOK) scheme by using it with the multiple-input multiple-output (MIMO) scheme; COOK has been recommended by the IEEE 802.15.7-2018 standard. By applying technologies, such as matched filter, region of interest, and MIMO, our proposed scheme promises to improve the performance of the conventional scheme by improving the data rate, communication distance, and bit error rate. By controlling the exposure time, the focal length in a single camera and using channel coding, our proposed scheme can achieve the communication distance of up to 20 m, with a low error rate.
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Lang, Wei Min, Yuan Cheng Zhu e Hu Sheng Li. "A Multi-Layer Security Architecture for Wireless Cognitive Sensor Networks in Smart Grids". Advanced Materials Research 546-547 (luglio 2012): 1107–12. http://dx.doi.org/10.4028/www.scientific.net/amr.546-547.1107.
Testo completoAbstract (sommario):
Wireless sensor networks have been extensively deployed in the electric power systems for sensing, transmission and control, which provide more opportunities for wireless low power radios to operate. As the next generation electricity system, the smart grid should possess the capability to transmit reliable and real-time information to the control centers of the utilities. In order to solve the issues such as heterogeneous coexistence, spectrum scarcity, tremendous data processing and Security guarantees, revolutionary communication architecture is urgently demanded. In this paper, after analyzing the hierarchical structure of smart grid and illustrating the principle of WCSN in smart grids, we propose the security architecture of wireless sensor networks based on cognitive radio for smart grids, which can be used as a reference to design and develop the Wireless Cognitive Sensor Network (WCSN) security schemes in the electric power systems.
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Ab Ghani, Mohd Ruddin, Siti Hajar Raman, Wan Nor Shela Ezwane Wan Jusoh, Mohd Ariff Mat Hanafiah e Jano Zanariah. "A Low Cost Wireless Data Acquisition System for Distribution Automation System". Applied Mechanics and Materials 699 (novembre 2014): 776–81. http://dx.doi.org/10.4028/www.scientific.net/amm.699.776.
Testo completoAbstract (sommario):
This paper analyzed the design and development of a 16F877A microcontroller-based wireless data acquisition system. Besides, it also discussed the possibility of different existing methodologies to be linked to field data acquisition from distribution automation systems. Various existing data transmission techniques were studied, especially for wireless systems such as satellite, radio, GSM and paging. The hardware and software implementations were included. The system was used for reading, storing and analyzing data which were obtained from DAS. The wireless communications were based on the GSM network. The laboratory results were compared with the simulation results to determine final conclusion.
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Gilmore, Rowan. "The world’s fastest wireless backhaul radio". Australian Journal of Telecommunications and the Digital Economy 3, n. 1 (27 aprile 2015): 1. http://dx.doi.org/10.18080/ajtde.v3n1.2.
Testo completoAbstract (sommario):
Fibre is commonly perceived to be the dominant transport mechanism for transferring data from access points back to a central office, where it is aggregated onto the core network. However, high speed and long range wireless backhaul remains a cost-effective alternative to fibre networks. In some areas, wireless backhaul is dominant and becoming more and more attractive. However, commercially available wireless backhaul systems do not meet the requirements for both high speed and long range at the same time with sufficiently low latency for some applications. Traditional microwave systems can achieve long transmission range, but the data rates are then limited to a few hundred megabits per second. Multi-gigabit per second wireless communications can be achieved using millimetre-wave (mm-wave) frequency bands, especially in E-band, but the practical transmission range has then always been a major weakness.In this article, the world’s first 5Gbps radio solution – and the fastest commercial backhaul product – developed by EM Solutions Pty Ltd with the Commonwealth Scientific and Industrial Research Organisation (CSIRO) – is described. As well as achieving a state-of-the-art data rate, other key design features include maximal path length, minimal latency, and constant antenna pointing under wind and tower vibration.
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Gilmore, Rowan. "The world’s fastest wireless backhaul radio". Journal of Telecommunications and the Digital Economy 3, n. 1 (27 aprile 2015): 1–15. http://dx.doi.org/10.18080/jtde.v3n1.2.
Testo completoAbstract (sommario):
Fibre is commonly perceived to be the dominant transport mechanism for transferring data from access points back to a central office, where it is aggregated onto the core network. However, high speed and long range wireless backhaul remains a cost-effective alternative to fibre networks. In some areas, wireless backhaul is dominant and becoming more and more attractive. However, commercially available wireless backhaul systems do not meet the requirements for both high speed and long range at the same time with sufficiently low latency for some applications. Traditional microwave systems can achieve long transmission range, but the data rates are then limited to a few hundred megabits per second. Multi-gigabit per second wireless communications can be achieved using millimetre-wave (mm-wave) frequency bands, especially in E-band, but the practical transmission range has then always been a major weakness.In this article, the world’s first 5Gbps radio solution – and the fastest commercial backhaul product – developed by EM Solutions Pty Ltd with the Commonwealth Scientific and Industrial Research Organisation (CSIRO) – is described. As well as achieving a state-of-the-art data rate, other key design features include maximal path length, minimal latency, and constant antenna pointing under wind and tower vibration.
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Poor, H. Vincent, e Rafael F. Schaefer. "Wireless physical layer security". Proceedings of the National Academy of Sciences 114, n. 1 (27 dicembre 2016): 19–26. http://dx.doi.org/10.1073/pnas.1618130114.
Testo completoAbstract (sommario):
Security in wireless networks has traditionally been considered to be an issue to be addressed separately from the physical radio transmission aspects of wireless systems. However, with the emergence of new networking architectures that are not amenable to traditional methods of secure communication such as data encryption, there has been an increase in interest in the potential of the physical properties of the radio channel itself to provide communications security. Information theory provides a natural framework for the study of this issue, and there has been considerable recent research devoted to using this framework to develop a greater understanding of the fundamental ability of the so-called physical layer to provide security in wireless networks. Moreover, this approach is also suggestive in many cases of coding techniques that can approach fundamental limits in practice and of techniques for other security tasks such as authentication. This paper provides an overview of these developments.
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Fedorenko, V. F., e V. E. Tarkivskiy. "Digital Wireless Technology to Measure Agricultural Performance". Agricultural Machinery and Technologies 14, n. 1 (24 marzo 2020): 10–15. http://dx.doi.org/10.22314/2073-7599-2020-14-1-10-15.
Testo completoAbstract (sommario):
When testing agricultural machinery in order to determine its functional indicators, the ability to wirelessly transmit data between sensors, measuring and information systems are important. (Research purpose) To develop methods and create wireless digital devices for determining the functional indicators of agricultural tractors and machines with the ability to wirelessly transmit data to a remote control point in real time. (Materials and methods) The authors assumed that it was possible to determine the slipping of driving wheels using an inertial navigation system. It was found that in order to calculate real-time indicators obtained using wireless technologies, it was necessary to determine the characteristics of the input signals of discrete sensors on the side of the measuring system. (Results and discussions) The authors substantiated a method for determining the period of incoming signals of discrete sensors with an accuracy of 0.001 seconds for wireless information transmission. They proposed the design of a slipping sensor for an energy vehicle driving wheels, the main element of which is an inertial wheel position sensor. They developed a discrete signal input module and an inertial slipping sensor with the possibility of wireless data transmission based on a radio system with a carrier frequency of 433 megahertz. During field tests, it was found that the accuracy of determining slippage using the inertial wireless sensor IP-291 does not exceed 1 percent; the range of stable radio communication from the tested object to the test control center reaches 1000 meters; the current indicators obtained through digital radio communication did not differ from the indicators obtained in the tractor cab. (Conclusions) The authors worked out an effective system for wireless information transfer with the ability to calculate the performance of the tested equipment in real time.
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Fu, Tingting, Huanghong Zhu, Han Hai e Haksrun Lao. "A Time-Overlapping Multiplex VLC System for End-Edge Data Transmission". Wireless Communications and Mobile Computing 2021 (5 agosto 2021): 1–12. http://dx.doi.org/10.1155/2021/9970972.
Testo completoAbstract (sommario):
Communication is one of the most important foundations in the Internet of Things. Although some cutting-edge technologies, such as 5G, have greatly empowered edge computing, electromagnetic interference and pollution make them impracticable in many environments. The visible light communication (VLC) is a new type of wireless communication technology with appealing benefits not presented in radio communications. VLC allows a lamp or other light source to not only serve as illumination but also simultaneously transmit data. Although traditional VLC multiplexing technologies have been able to achieve a high-speed data transmission rate, they require all receivers to use the same modulation means. In many scenarios, various-type receivers coexist; it is costly to incorporate multiple senders to implement adaptive content distribution in on-demand services. In this paper, we propose a new type of VLC multiplexing system, which realizes end-edge data transmission through pulse position modulation (PPM), pulse width modulation (PWM), and pulse amplitude modulation (PAM) simultaneously. Therefore, one edge server can serve multiple types of end-users without interference. In order to evaluate the performance of the system, we conduct experiments with different settings of communication distance, communication angle, and different environmental light conditions. For three modulations, the proposed system can achieve a transmission speed three times as that for a single modulation, and reach the accuracy rate of up to 99% within the proper communication range.
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Michler, O. "Outdoor radiolinks for 2.4 GHz-frequencies: measurement results and experiences within the radio communication network “Intermobil Region Dresden"". Advances in Radio Science 1 (5 maggio 2003): 301–7. http://dx.doi.org/10.5194/ars-1-301-2003.
Testo completoAbstract (sommario):
Abstract. The radio communication network “Intermobil Region Dresden" was developed and built up for data transmission of traffic videos and other traffic data. It uses Pointto- Point (PtP) and Point-to-Multipoint (PtM) bridges, forming the backbone structure. The traffic camera radio clients link up with Accesspoints, installed at the nodal points of the backbone. This paper analyses the physical and technical conditions, building up such radio communication networks. The radio channel properties (e.g. total path loss, multipath propagation) and the technical parameters (e.g. transmission power, sensitivity, antenna gain) belong to this conditions. Based on calculation and spreading measurements it is shown, that reserves have to be considered during the planning already. As well special problems, like Fresnel-zone clearance and shadowing are discussed. The choice of the antenna plays a key role for planning and building of wireless networks. It determines decisively the range and gives an important contribution to elimination of wireless disturbances (interferences). Dependent on topological facts, installation environment and wireless distance omnidirectional-, yagi-, patch- and parabol-antennas are used. Based on antenna measurements the paper discusses the use and property of decoupling. WLANs are working in the license free 2.4 GHz-band. The number of radio systems in this band increases permanently, which leads to a lot of interferences among each other. The paper makes a classification of possible interference sources and discusses their influence on transmission quality. Technical solutions are shown for increase interference robustness.
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Zhang, Zhen, Yibing Li, Chao Wang, Meiyu Wang, Ya Tu e Jin Wang. "An Ensemble Learning Method for Wireless Multimedia Device Identification". Security and Communication Networks 2018 (15 ottobre 2018): 1–9. http://dx.doi.org/10.1155/2018/5264526.
Testo completoAbstract (sommario):
In the last decade, wireless multimedia device is widely used in many fields, which leads to efficiency improvement, reliability, security, and economic benefits in our daily life. However, with the rapid development of new technologies, the wireless multimedia data transmission security is confronted with a series of new threats and challenges. In physical layer, Radio Frequency Fingerprinting (RFF) is a unique characteristic of IoT devices themselves, which can difficultly be tampered. The wireless multimedia device identification via Radio Frequency Fingerprinting (RFF) extracted from radio signals is a physical-layer method for data transmission security. Just as people’s unique fingerprinting, different Internet of Things (IoT) devices exhibit different RFF which can be used for identification and authentication. In this paper, a wireless multimedia device identification system based on Ensemble Learning is proposed. The key technologies such as signal detection, RFF extraction, and classification model are discussed. According to the theoretical modeling and experiment validation, the reliability and the differentiability of the RFFs are evaluated and the classification results are shown under the real wireless multimedia device environments.
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Elsanousi, A., e S. Oztürk. "Performance Analysis of OFDM and OFDM-MIMO Systems under Fading Channels". Engineering, Technology & Applied Science Research 8, n. 4 (18 agosto 2018): 3249–54. http://dx.doi.org/10.48084/etasr.2209.
Testo completoAbstract (sommario):
Fourth-generation (4G) wireless communication system is mainly based on MIMO (multiple input and multiple output) and OFDM (orthogonal frequency division multiplexing). The combination of these two techniques leads to a better system, known as OFDM-MIMO system, providing higher capacity and data rate. This paper demonstrates the BER (bit error rate) performance of OFDM and OFDM-MIMO system using convolution code to encrypt the data stream that can be sent over communication channels. Simulation is made on Matlab using three different channels (AWGN, Rician and Rayleigh). The simulation results show that the combined system has better performance compared to OFDM system. The practical part of this study was conducted by using two USRPs B210 (universal software radio peripheral) for transmitting and receiving, two antennas were used during transmission for both sides. The transmitted signal is successfully recovered.
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Callejas-Cuervo, Mauro, Manuel Andrés Vélez-Guerrero e Andrea Catherine Alarcón-Aldana. "Characterization of Wireless Data Transmission over Wi-Fi in a Biomechanical Information Processing System". Revista Facultad de Ingeniería 29, n. 54 (6 novembre 2019): e10228. http://dx.doi.org/10.19053/01211129.v29.n54.2020.10228.
Testo completoAbstract (sommario):
This paper presents a characterization of the wireless transmission of biomechanical signals in an embedded system, where a TCP protocol is used in an IEEE 802.11 communications network (Wi-Fi). The embedded system under study, called Imocap, allows the collection, analysis and transmission of biomechanical signals in real-time for various applications, among which the analysis of the movement of the lower and upper extremities and the operation of various control systems stand out. To accomplish this, Imocap is equipped with a Wi-Fi transceiver module (ESP8266) and various input and output peripherals. The wireless communication performance of Imocap, exposed in this paper, was analyzed through different tests in miscellaneous conditions like indoors, outdoors and in the presence of interference, noise and other wireless networks. The different test protocols conducted result in the Imocap system: 1) has a maximum effective range of 45.6 m when in Access Point mode; 2) has a maximum effective range of 44.3 m when in Station mode. In indoors and under the same conditions, the Imocap system: 3) has a maximum effective range of 81.25 m2, either Access Point or Station mode. The results showed that the transmission of biomechanical information through Wi-Fi using the TCP protocol is efficient and robust, both indoors and outdoors, even in environments of radio frequency interference. The use of this protocol is emphasized since its use allows the transmission of packages to be carried out in a controlled manner, allowing the error handling and recovery. In this way, it is possible to carry out efficient and robust wireless communication through embedded and portable devices, focusing mainly on areas such as medicine, telemedicine and telerehabilitation.
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Gueye, Ibrahima, Ibra Dioum, Idy Diop, K. Wane Keita, Papis Ndiaye, Moussa Diallo e Sidi Mohamed Farssi. "Performance of Hybrid RF/FSO Cooperative Systems Based on Quasicyclic LDPC Codes and Space-Coupled LDPC Codes". Wireless Communications and Mobile Computing 2020 (30 dicembre 2020): 1–15. http://dx.doi.org/10.1155/2020/8814588.
Testo completoAbstract (sommario):
Free space optical (FSO) communication systems provide wireless line of sight connectivity in the unlicensed spectrum, and wireless optical communication achieves higher data rates compared to their radio frequency (RF) counterparts. FSO systems are particularly attractive for last mile access problem by bridging fiber optic backbone connectivity to RF access networks. To cope with this practical deployment scenario, there has been increasing attention to the so-called dual-hop (RF/FSO) systems where RF transmission is used at a hop followed by FSO transmission to another. In this article, we study the performance of cooperative transmission systems using a mixed RF-FSO DF (decode and forward) relay using error-correcting codes including QC-LDPC codes at the relay level. The FSO link is modeled by the gamma-gamma distribution, and the RF link is modeled by the Additive White Gaussian Noise (AWGN) model. Another innovation in this article is the use of cooperative systems using a mixed FSO/RF DF relay using quasicyclic low-density parity check (QC-LDPC) codes at the relay level. We also use the space-coupled low-density parity check (SC-LDPC) codes on the same scheme to show its importance in cooperative optical transmission but also in hybrid RF/FSO transmission. The latter will be compared with QC-LDPC codes. The use of mixed RF/FSO cooperative transmission systems can improve the reliability and transmission of information in networks. The results demonstrate an improvement in the performance of the cooperative RF/FSO DF system based on QC-LDPC and SC-LDPC codes compared to RF/FSO systems without the use of codes, but also to the DF systems proposed in the existing literature.
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Almadani, Yousef, David Plets, Sander Bastiaens, Wout Joseph, Muhammad Ijaz, Zabih Ghassemlooy e Sujan Rajbhandari. "Visible Light Communications for Industrial Applications—Challenges and Potentials". Electronics 9, n. 12 (16 dicembre 2020): 2157. http://dx.doi.org/10.3390/electronics9122157.
Testo completoAbstract (sommario):
Visible Light Communication (VLC) is a short-range optical wireless communication technology that has been gaining attention due to its potential to offload heavy data traffic from the congested radio wireless spectrum. At the same time, wireless communications are becoming crucial to smart manufacturing within the scope of Industry 4.0. Industry 4.0 is a developing trend of high-speed data exchange in automation for manufacturing technologies and is referred to as the fourth industrial revolution. This trend requires fast, reliable, low-latency, and cost-effective data transmissions with fast synchronizations to ensure smooth operations for various processes. VLC is capable of providing reliable, low-latency, and secure connections that do not penetrate walls and is immune to electromagnetic interference. As such, this paper aims to show the potential of VLC for industrial wireless applications by examining the latest research work in VLC systems. This work also highlights and classifies challenges that might arise with the applicability of VLC and visible light positioning (VLP) systems in these settings. Given the previous work performed in these areas, and the major ongoing experimental projects looking into the use of VLC systems for industrial applications, the use of VLC and VLP systems for industrial applications shows promising potential.
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Zavvari, Azam, e Ahmed Patel. "Critical Evaluation of RFID Security Protocols". International Journal of Information Security and Privacy 6, n. 3 (luglio 2012): 56–74. http://dx.doi.org/10.4018/jisp.2012070103.
Testo completoAbstract (sommario):
Radio Frequency Identification (RFID) system is a low-cost contactless automatic identification technology; and barcode as a traditional technology is now broadly replaced by RFID systems to make objects more manageable in supply chains and other enterprises. This technology is operational in open wireless communication spaces whereby its transmission signals can be easily accessed resulting in security problems. Consequently, it becomes an absolute necessity to develop efficient security protocols to protect the data against various attacks. This paper outlines a critical evaluation of the RFID systems, the security and privacy issues in the RFID security protocols, the EPCglobal Class-1 Generation-2 standard as it is an international standard, its lower cost of implementation, and high speed data transmission and operation.
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Marjan, Shah, Lin Bai e Chao Han. "Split Antenna Array in Millimeter Wave for Secure Vehicular Communication". MATEC Web of Conferences 173 (2018): 02024. http://dx.doi.org/10.1051/matecconf/201817302024.
Testo completoAbstract (sommario):
The small carrier wavelength at millimeter wave (mm-wave) frequencies features a large number of co-located antennas. Wireless networks with directional antennas using beamforming at mm-wave also have potential to provide an enhanced security in the vehicular communication system. Large bandwidth of mm-wave can provide auto drive and safety linked functionalities, However, safety and efficiency of the vehicular transportation system can be jeopardized by many kinds of attacks by eavesdroppers, physical layer security can work as an extra layer of security for wireless communication systems. To secure communication in-between Vehicles, an Analog precoding based physical Layer technique for mm-wave vehicular communication systems is presented in the paper. The proposed technique works by exploiting large Antenna arrays at millimeter waves and provide a secure directional transmission with low power consuming phase shifters and single Radio Frequency Chain. Larger antennas arrays are split into two subsets, one for transmission of data and another for generating noise. The proposed technique offers improved coherent transmission at the legitimate receiver and by introducing artificial noise to the eavesdroppers at random directions. This outcome in low SNR for the eavesdroppers, hence hacking information becomes extremely difficult. Numerical and Simulation results show the superior performance of the proposed technique compared to traditional physical layer security technique and conventional array technique.
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Estrela, Vania V. "SDR-Based High-Definition Video Transmission for Biomedical Engineering". Medical Technologies Journal 4, n. 3 (7 dicembre 2020): 584–85. http://dx.doi.org/10.26415/2572-004x-vol4iss3p584-585.
Testo completoAbstract (sommario):
Background: Software-Defined Radio (SDR) frameworks from cellular telephone base stations, e.g., Multiservice Distributed Access System (MDAS) and small cells, employ extensively integrated RF agile transceivers. The Internet of Medical Things (IoMT) is the collection of medical devices and applications that connect to healthcare IT systems through online computer networks. Medical devices equipped with Wi-Fi allow M2M communication, which is the backbone of IoMT and associated devices linked to cloud platforms containing stored data to be analyzed. Examples of IoMT include remote patient monitoring of people with chronic or long-term conditions, tracking patient medication orders and the location of patients admitted to hospitals, and patients' wearables to send info to caregivers. Infusion pumps connected to dashboards and hospital beds rigged with sensors measuring patients' vital signs are medical devices that can be converted to or deployed as IoMT technology.
Methods: This work proposes an SDR architecture to allow wireless High-Definition (HD) video broadcast for biomedical applications. This text examines a Wideband Wireless Video (WWV) signal chain implementation using the transceivers, the data transmitted volume, the matching occupied RF bandwidth, the communication distance, the transmitter’s power, and the implementation of the PHY layer as Orthogonal Frequency Division Multiplexing (OFDM) with test results to evade RF interference.
Results: As the IoMT grows, the amount of possible IoMT uses increases. Many mobile devices employ Near Field Communication (NFC) Radio Frequency Identification (RFID) tags allowing them to share data with IT systems. RFID tags in medical equipment and supplies allow hospital staff can remain aware of the quantities they have in stock. The practice of using IoMT devices to observe patients in their homes remotely is also known as telemedicine. This kind of treatment spares patients from traveling to healthcare facilities whenever they have a medical question or change in their condition.
Conclusion: An SDR-based HD biomedical video transmission is proposed, with its benefits and disadvantages for biomedical WWV are discussed. The security of IoMT sensitive data is a developing concern for healthcare providers.
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Kabalan, Ali, Salim Faci, Anne-Laure Billabert, Frédérique Deshours e Catherine Algani. "Direct and external modulation of IF over fiber systems for 60 GHz wireless applications". International Journal of Microwave and Wireless Technologies 8, n. 3 (16 aprile 2015): 597–602. http://dx.doi.org/10.1017/s1759078715000586.
Testo completoAbstract (sommario):
Wireless domestic applications involving high data rates are required to work on millimeter wave band. Signal propagation at this frequency range is affected by walls and oxygen absorption which limits communication distances to few meters in one room. Radio coverage can be extended to other rooms by optical links. Performances of such photonic systems are dependent on optoelectronic devices, electrical driving, and receiver circuits. In this paper, radio-over-fiber (RoF) links based on the intensity modulation and direct detection technique are investigated for transmission of a broadband OFDM signal. Direct and external modulations are exploited to analyze system performances according to the ultra wideband (UWB) millimeter-band standard. To avoid component tolerances at high frequencies, an intermediate frequency modulation of the optical transducers is chosen. Optoelectronic and optical components of RoF links are modeled by equivalent electrical circuits with consideration of noise and nonlinearities. These models are validated in system simulation by error vector magnitude evaluation with a measurement setup according to the UWB centimeter-band standard.
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Daldal, Nihat, Majid Nour e Kemal Polat. "The Methods toward Improving Communication Performance in Transparent Radio Frequency Signals". Mathematical Problems in Engineering 2020 (24 aprile 2020): 1–8. http://dx.doi.org/10.1155/2020/7175864.
Testo completoAbstract (sommario):
In wireless digital communications, amplitude-shift keying (ASK) and frequency-shift keying (FSK) modules are often used and radio frequency (RF), communication synchronization, and noise problems affect the performance very much. In particular, the sending of byte-type data called synchronous and preamble before sending data in intermodule communication increases the sent data and decreases the speed. Also, the microcontroller at the output of the RF receiver module continuously listens to the RF noise and analyzes incoming data, but this increases the processing load of the microcontroller. Moreover, it reduces the speed of performing other operations. In this study, a transparent RF transmitter and receiver have been investigated, and methods for increasing the communication performance of the modules have been proposed and performed. Two of the proposed methods prevented the continuous listening of the microprocessor in the RF receiver structure so that the microprocessor can be used with other processes. In other methods, the compression of the data size was achieved because the transmission of a series of data in RF communication systems was limited to a certain extent. In the last section of the study, since the RF modules have failed to transmit the data due to corruption in the extended data dimensions, the bit carrier control security code has been created for the data series and more healthy communication has been performed.
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Авдєєнко, Гліб Леонідович, Сергій Георгійович Бунін e Теодор Миколайович Наритник. "ТЕРАГЕРЦОВІ ТЕХНОЛОГІЇ В ТЕЛЕКОМУНІКАЦІЙНИХ СИСТЕМАХ. ЧАСТИНА 2. ДОСЛІДЖЕННЯ ТА МОДЕЛЮВАННЯ ПЕРЕДАВАННЯ ТЕЛЕВІЗІЙНИХ СИГНАЛІВ СТАНДАРТУ DVB-C І ІМПУЛЬСНОГО НАДШИРОКОСМУГОВОГО СИГНАЛУ РАДІОЛІНІЄЮ ТЕРАГЕРЦОВОГО ДІАПАЗОНУ". RADIOELECTRONIC AND COMPUTER SYSTEMS, n. 3 (30 ottobre 2018): 80–96. http://dx.doi.org/10.32620/reks.2018.3.09.
Testo completoAbstract (sommario):
The laboratory testbed of a digital simplex radio-relay system of the terahertz range has been studied for the first time in practical terms. It consists of the receiver and transmitter parts of 130÷134 GHz frequency range and a digital modem with a channel data transmission of up to 1200 Mbps for a communication point-to-point distance under normal conditions within 1 km. It is shown that the proposed telecommunication system, which implements the concept of the creation of software-defined radio systems based on Wi-Fi technology, can be highly productive in the next generation mobile communication networks providing the appropriate transmission speeds, reliability, and security. It is studied the parameters of multichannel digital TV signal DVB-C standard when it is transmitted through the testbed of the transmitter and receiver parts of 130 GHz band. The results of the research showed that the application of lower part of terahertz frequency band (130 GHz) with a bandwidth of 24 MHz allows the transmission of three DVB-C television broadcasting channels with a total transport speed of 125 Mbit/s with a high subjective quality of TV programs. The results of the simulation of impulse ultrawideband (IR-UWB) signal transmission by the wireless link of terahertz band are presented. The results of researches of changes of IR-UWB Gaussian monocycle in the transmitter part and its reception by the receiver part of 130.4÷131.5 GHz terahertz band are presented for the first time. On the basis of the results of the research, the requirements for parameters of terahertz wireless link are formulated to ensure acceptable quality of ultrawideband impulse signals receiving. Development of the transmitter and receiver parts of radio relay system of the terahertz range has no direct current analogs in Ukraine. It can provide a significant breakthrough in the development of the telecommunications industry. The obtained research results will also contribute to the development of telecommunications-related industries, in particular: radio astronomy, inter-satellite communication, radar systems, medicine, etc.
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Khan, Rabia, e Dushantha Nalin K. Jayakody. "Full Duplex Component-Forward Cooperative Communication for a Secure Wireless Communication System". Electronics 9, n. 12 (10 dicembre 2020): 2102. http://dx.doi.org/10.3390/electronics9122102.
Testo completoAbstract (sommario):
The technological breakthrough in the form of Internet of Things (IoT), Big data and connected world is increasing the demand of better spectrum utilization. Half-Duplex (HD) transmission is mostly used in the earlier communication systems. The high transmission demand requires the better utilization of the existing spectrum. There are several possible ways to overcome the problem of better spectrum usage. In-Band Full Duplex (IBFD) is one of the techniques that can double the Spectral Efficiency (SE) in a Beyond 5G (B5G) communication system. In this paper, our aim is to use the spectral efficient IBFD scheme to improve the security of the system with minimum interference. The interference can be reduced by the addition of orthogonality between the transmitted and received signal of a relay. A component-forward scheme is proposed in this paper to create such orthogonality. For achieving the desired aim, IBFD is used with Device-to-Device (D2D), Artificial Noise (AN), Modulation based orthogonalization, Radio Frequency Energy Harvesting (RFEH) and proposed Full-Duplex Component Forward (FD-CF) algorithm for multiple relays. We also use non-linear harvested power as one of the sources to reuse the exiting power for evaluating the system performance. The derivation of Secrecy Outage Probability (SOP) and throughput is derived in this paper for the FD-CF cooperative communication and is explored with and without non-linear RFEH. The simulation results show the comparison between the component-forward and decode-and-forward communication with one or more relays.
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Dziadak, Bogdan, Lukasz Makowski e Andrzej Michalski. "Some Practical Problems of Communications Reliability in Enviromental Monitoring Systems". Metrology and Measurement Systems 20, n. 3 (1 settembre 2013): 337–50. http://dx.doi.org/10.2478/mms-2013-0029.
Testo completoAbstract (sommario):
Abstract In this paper, some issues of building a reliable, distributed measurement system for monitoring of water quality in reservoir Lake Dobczyckie are presented. The system is based on a measurement station that has the shape of a floating buoy which is supposed to be at anchor on the reservoir. Wireless data transmission problems that were encountered during the development of the buoy, modeling a radio link, and measurements of actual signal strength on the reservoir are discussed. A mathematical approach to procedures of early situation assessment was conducted, and specialized procedures were designed for measurement stations of the system. It is also discussed how such computations can improve a qualitative assessment of system performance in terms of real-time messaging
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Senthamarai, C., e N. Malmurugan. "Efficient Spectral Allocation for Cognitive Full Duplex Relay Network Systems Based Soft Computing Technique". Current Signal Transduction Therapy 15, n. 1 (31 luglio 2020): 46–55. http://dx.doi.org/10.2174/1574362413666180831105203.
Testo completoAbstract (sommario):
Background: Due to the huge development of wireless devices and mobile data traffic had gained attention towards identifying accurate solutions for more proficient utilization of the wireless spectrum. An essential issue confronting the future in wireless systems is to identify the appropriate spectrum bands to satisfy the request of future administrations. While the greater part of the radio spectrum is allocated to various services, applications and users show that spectrum usage is quite low. Materials and Methods: The spectrum sensing is performed at the start of each time slot before the data transmission. As a promising framework to improve the spectrum utilization, Cognitive Radio (CR) technique has the immense potential to meet such a necessity by permitting unlicensed users to exist together in licensed bands. In this paper Cognitive radio and Full-Duplex (FD) based two-way relay communications are developed to enhance spectrum utilization for multichannel and to decrease the false alarm rate. Results: To solve the optimization problems in spectral efficiency, soft computing techniques is proposed to minimize the self-interference and delay to the licensed users. In this proposed work the kurtosis parameter is used for channel detection to determine whether the signal is present or not. Conclusion: The performance results of the proposed method are evaluated in terms of spectral allocation and outage probability which achieves better performance than the existing Multi- Objective Genetic Algorithm (MOGA) optimization.
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Partha, C. G. I., I. N. Budiastra, A. A. N. Amrita e I. M. Suartika. "Remote Sensing Systems At The Rocket's Payload Test". Journal of Electrical, Electronics and Informatics 2, n. 2 (18 dicembre 2018): 44. http://dx.doi.org/10.24843/jeei.2018.v02.i02.p05.
Testo completoAbstract (sommario):
Aviation technology and space is one of the leading technology for developed countries, especially in the form of rocket technology and payload. Countries that are capable of mastering these technologies will be respected by countries all over the world. Indonesia as the island nation and the State's large and extensive maritime already should have independence in the mastery of the technology of the rocket and payload. Therefore, continuous efforts are required to achieve independence, including through enhancing aviation technology and space technology, particularly at early stages the rocket and payload. Remote Sensing Systems At the rocket's Payload was Test remote monitoring system image capture and the attitude of the launch payload through the computer screen (display) continuously (real-time) data obtained from sensors that are mounted on the rocket's payload. 3D point (x, y, z) must be expressed as a graph visualization perspective drawings of rockets with the appropriate direction. The radar conducted computer GS (Ground Segment) or Ground Control Station (GCS). The result of the attitude of the Rocket Test launch Payloads have been able to do the communication data transmission of images and data for 3D (x, y, and z) in real-time to the Ground segment. Wireless communication uses radio telemetry frequency 433 MHz, power of 100 mW, the distance range obtained in this study a maximum of 1000 meter in conditions in the air and without obstruction.
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Grekhov, Andrii, Vasyl Kondratiuk e Svitlana Ilnytska. "Data Traffic Modeling in RPAS/UAV Networks with Different Architectures". Modelling 2, n. 2 (28 marzo 2021): 210–23. http://dx.doi.org/10.3390/modelling2020011.
Testo completoAbstract (sommario):
Deploying of Fifth Generation and Beyond Fifth Generation (5G/B5G) wireless networks will require wider coverage, flexible connectivity, low latency, support for a large number of user devices, and more bandwidth. This article explores the paradigm that Remotely Piloted Air Systems (RPASs) or Unmanned Aerial Vehicles (UAVs) are integrated as a communication platform with cellular networks using radio access. It is important to know the possibilities and ways of such integration for effective interaction with RPASs. This paper studies the issues of ensuring the required Quality of Service (QoS) during heavy traffic and the choice of necessary data transmission modes for this. Models of RPAS communication channels with different architectures were created. The relationships between models’ performance and traffic parameters were obtained using the NetCracker Professional 4.1 software. The dependencies of the Average Utilization (AU) on the Transaction Size (TS) were analyzed. The effects of different bandwidths and the Bit Error Rate (BER) were studied. The traffic characteristics in all models were compared.
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Pratiknyo, Gesit, M. Sigit Purwanto, Erpan Sahiri e Muladiyono Muladiyono. "DESIGN OF THE DATA TRANSMISSION BETWEEN THE EXERSICE SMART MINE WITH GROUND STATION USING LORA". JOURNAL ASRO 11, n. 1 (31 gennaio 2020): 191. http://dx.doi.org/10.37875/asro.v11i1.217.
Testo completoAbstract (sommario):
Wireless data communication system through communication radio is one of the important points of informationdelivery process in TNI AL, It relates to the process of delivering information on the field that is difficult to obtaincommunication network via internet. The use of portable and strong communications against jammedinterference and other adjacent frequency interference becomes a fundamental necessity. The use of the UHFfrequency communication system is one of the efficient communication, With the high frequency of positivelyresulting in the physical size of the antenna is increasingly smaller. The purpose of designing datacommunication system devices between exercise smart mine and the ground station using Lora. In planning thiscommunication system uses the Lora SX1278 module as a data transmitter (Tx) and receiver data device (Rx).On the transmitter side (Tx) Lora uses the Arduino Mega 2560 microcontroller as the core or brain system. Onthe side of the receiver (Rx) Lora uses Arduino Uno R3 as the process data unit received by the Lora receiver.The main function of Arduino Uno as an intermediary to be able to transfer data to a PC or laptop device as aground station monitoring through USB communication channels. From the design, testing, and discussion ofresearch results during the preparation and manufacture of this final task obtained the results as expected. Thatthe design of data communication systems using Lora can be obtained a maximum range of 200 meters withthe condition of building obstructed. The ability of the Lora SX1278 module to receive data and transmit datafrom the GPS, pressure sensors and acoustic sensors is well received by the ground station, based on the datatransmitted via the Lora SX1278 module transmitter.Keywords: Lora SX1278, Arduino Mega 2560, Arduino Uno R3
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Hussien, Anas Ali, e Adnan Hussein Ali. "Comprehensive investigation of coherent optical OFDM-RoF employing 16QAM external modulation for long-haul optical communication system". International Journal of Electrical and Computer Engineering (IJECE) 10, n. 3 (1 giugno 2020): 2607. http://dx.doi.org/10.11591/ijece.v10i3.pp2607-2616.
Testo completoAbstract (sommario):
Given the growing need for long haul transmission that requires a high rate of data, the orthogonal frequency division multiplexing scheme (OFDM), is regarded as a technique with high potentials for high-capacity optical networks. OFDM transmits over both optical and wireless channels, with the data distributed over a huge amount of the subcarrier, and the data is distributed over a huge number of subcarriers. OFDM achieves RF signal for a long-haul transmitting by utilizing Radio over Fiber (RoF) system, which is known to produce higher orthogonality of the OFDM modulated signal designed for the wireless network. RoF systems comprise of heterogeneous networks designed through the use of wireless and optical links. The aim of this paper is to carry out an investigation of the performance of the external modulation in RoF links, while analyzing the shortcomings caused by the various elements of the optical system. The Mach–Zehnder modulator (MZM) can be applied in external modulation, and exhibits a more robust performance when implemented with the OFDM modulation technique.
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Wydra, Michal, Pawel Kubaczynski, Katarzyna Mazur e Bogdan Ksiezopolski. "Time-Aware Monitoring of Overhead Transmission Line Sag and Temperature with LoRa Communication". Energies 12, n. 3 (5 febbraio 2019): 505. http://dx.doi.org/10.3390/en12030505.
Testo completoAbstract (sommario):
The techniques of Dynamic Line Rating (DLR) for Overhead Transmission Line (OTL)’s are currently dynamically developed. DLR systems typically rely on weather, temperature, inclination, and current measurements to calculate tension and sag, where sensors need to be installed directly on wires. Such systems are very reliable and ensure high accuracy in determining maximum allowable current. However, their installation may require switching off the transmission line from the operation. In order to receive precise values regarding the actual operating conditions of the whole transmission line, DLR sensors measuring wire temperature or tension should be installed at many points of OTL. The minimum number of installation points should cover at least each tension section and critical spans, thereby increasing installation costs. The alternative method that allows for the monitoring of OTL is the use of the vision system based on cameras. Installed on the OTLs’ poles, cameras can take photos which, appropriately processed, can provide data about the sag and temperature of wires, without the necessity of switching OTL from the operation for installation or further maintenance. Such a vision system facilitates also data transmission, because it does not require measurement data to be transmitted from the sensor station installed on the wire to the base station located on the pole (for instance, via radio). This article aims to present the concept of a vision system that monitors sag and temperature of Overhead Transmission Lines (OTLs)’ using Long Range (LoRa) wireless communication and data transmission. The developed system consists of a camera and a microcomputer equipped with LoRa communication module. The whole system monitors OTLs’ spans by taking photos, processing images for wire sag-temperature estimation, and sending results to the operator’s Supervisory Control And Data Acquisition (SCADA). The system communication architecture is also proposed and investigated for data transmission time when monitoring the whole OTL.
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Hussein Ali, Adnan, Hayder Jasim Alhamdane e Begared Salih Hassen. "Design analysis and performance evaluation of the WDM integration with CO-OFDM system for radio over fiber System". Indonesian Journal of Electrical Engineering and Computer Science 15, n. 2 (1 agosto 2019): 870. http://dx.doi.org/10.11591/ijeecs.v15.i2.pp870-878.
Testo completoAbstract (sommario):
<span>The optical communication and wireless networks can be integrated to increase the capacity and mobility with decrease the costs in the access networks. Optical communication is considered a Fiber optic communication that can be used for wired and wireless communication. The problems of Fiber optic communication have a solution represented by Radio over fiber (RoF) which can control many base stations (BSs) that connect to a central station (CS) with an optical fiber. The Coherent optical OFDM (CO-OFDM) have concerned a great interest due to the high spectral efficiency and strength to the fiber dispersion, also it can be considered as a promising candidate when used in long haul optical fiber transmission systems. The integration of the wavelength division multiplexing system (WDM) with (CO-OFDM) system for increasing the system performance as well as achieving high data rates. The simulation of WDM-ROF and (WDM-CO-OFDM) with an optisystem simulator to analyze the RF spectrum, spectrum signal visualizers, and constellation diagrams. The proposed of integration of WDM and RoF-OFDM system is to achieve 100 km fiber length using 4QAM sequence bit, and the received power with electrical and optical amplifications by using 10 Gbps data signal.</span>
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Rauniyar, Ashish, Paal Engelstad e Olav Østerbø. "RF Energy Harvesting and Information Transmission Based on NOMA for Wireless Powered IoT Relay Systems". Sensors 18, n. 10 (27 settembre 2018): 3254. http://dx.doi.org/10.3390/s18103254.
Testo completoAbstract (sommario):
Amidst the rapid development of the fifth generation (5G) networks, Internet of Things (IoT) is considered as one of the most important part of 5G next generation networks as it can support massive object communications. These massive object communications in the context of IoT is expected to consume a huge power. Furthermore, IoT sensors or devices are rather power constrained and are mostly battery operated. Therefore, energy efficiency of such network of IoT devices is a major concern. On the other hand, energy harvesting (EH) is an emerging paradigm that allows the wireless nodes to recharge themselves through radio frequency (RF) signals directed to them from the source node and then relaying or transmitting the information. Although a myriad of works have been carried out in the literature for EH, the vast majority of those works only consider RF EH at the relay node and successfully transmitting the source node data. Those approaches do not consider the data transmission of the relay node that may be an energy deprived IoT node which needs to transmit its own data along with the source node data to their respective destination nodes. Therefore, in this paper, we envisioned a RF EH and information transmission system based on time switching (TS) relaying, power splitting (PS) relaying and non-orthogonal multiple access (NOMA) which is suitable for wireless powered IoT relay systems. A source node information data is relayed through power constrained IoT relay node I o T R that first harvests the energy from source node RF signal using either TS and PS relaying protocol and then transmits the source node information along with its information using NOMA protocol to the respective destination nodes. Considering NOMA as a transmission protocol, we have mathematically derived analytical expressions for TS and PS relaying protocol for our proposed system. We have also formulated an algorithm to find out optimal TS and PS factor that maximizes the sum-throughput for our proposed system. Our proposed system analytical results for TS and PS protocol are validated by the simulation results.
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Ali, Adnan, e Alaa Farhood. "Design and Performance Analysis of the WDM Schemes for Radio over Fiber System With Different Fiber Propagation Losses". Fibers 7, n. 3 (26 febbraio 2019): 19. http://dx.doi.org/10.3390/fib7030019.
Testo completoAbstract (sommario):
The integration of optical and wireless networks increases mobility and capacity and decreases costs in access networks. Fibre optic communication can be considered optical communication that combines the methodologies of two communications, and it may be utilised in systems of wired and wireless communication. The solution for many problems is radio over fibre (RoF) because it can control many base stations (BS) that are connected to a central station (CS) with an optical fibre. The received RoF signal head for in a low quality; thus, many factors will result in some problems such as a high bit error rate (BER) and low Q-factor values, and the receiver might not be operating in a high data rate network. Wavelength division multiplexing (WDM) network can offer a solution to these problems where the transmission of different signals can be done with a single-mode fibre. BER should be reduced to assured values, and the Q-factor must be increased. The investigation of WDM-RoF with different lengths of fibre at various channel spacing will be simulated using Optisystem software, and the RoF’s receiver performance is measured and analyzed depending on the acquired BER, the value of the Q-factor, and the height of the opening of the eye diagram. The degradation factors effect such as attenuation and dispersion are significantly limited with the addition of an EDFA amplifier to a Single Mode Fibre (SMF).
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Kimionis, John, Apostolos Georgiadis, Spyridon Nektarios Daskalakis e Manos M. Tentzeris. "A printed millimetre-wave modulator and antenna array for backscatter communications at gigabit data rates". Nature Electronics 4, n. 6 (giugno 2021): 439–46. http://dx.doi.org/10.1038/s41928-021-00588-8.
Testo completoAbstract (sommario):
AbstractFuture devices for the Internet of Things will require communication systems that can deliver higher data rates at low power. Backscatter radio—in which wireless communication is achieved via reflection rather than radiation—is a low-complexity approach that requires a minimal number of active elements. However, it is typically limited to data rates of hundreds of megabits per second because of the low frequency bands used and the modulation techniques involved. Here we report a millimetre-wave modulator and antenna array for backscatter communications at gigabit data rates. This radiofrequency front-end consists of a microstrip patch antenna array and a single pseudomorphic high-electron-mobility transistor that supports a range of modulation formats including binary phase shift keying, quadrature phase shift keying and quadrature amplitude modulation. The circuit is additively manufactured with inkjet printing using silver nanoparticle inks on a flexible liquid-crystal polymer substrate. A millimetre-wave transceiver is also designed to capture and downconvert the backscattered signals and route them for digital signal processing. With the system, we demonstrate a bit rate of two gigabits per second of backscatter transmission at millimetre-wave frequencies of 24–28 GHz, and with a front-end energy consumption of 0.17 pJ per bit.
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Skierucha, W., A. M Wilczek e R. T Walczak. "Application of smart sensors in the measurement of soil physical parameters ". Research in Agricultural Engineering 50, No. 3 (8 febbraio 2012): 96–102. http://dx.doi.org/10.17221/4933-rae.
Testo completoAbstract (sommario):
The study presents the project and partial implementation of a modern monitoring system for the measurement of soil physical parameters. It is provided with smart sensors equipped with signal conversion electronics, individual identification and communication means decreasing the complexity of the measurement system and also the measurement errors that can appear during analog signal transmission along the cables from the sensors to the measuring unit. The applied wireless communication system operates in the 433MHz ISM (Industrial, Scientific, Medical) licence free frequency band for transmission of commands and data between a remote PC compatible computer (Master unit) and the smart sensors (Slave units) in the distance of several hundred meters. The presented partial implementation of the system measures the temperature at several locations in the soil profile in field conditions and communicates with the host PC computer in wireless way. The developed hardware and software is intended to be adapted to more complex monitoring systems working in compliance with IEEE 1451 smart transducer interface standard and covering large areas as an element of air-borne or satellite remote sensing and serve for ground reference measurements. It is shown that the currently available technical means enable to apply smart sensors and wireless communication in the environmental monitoring in the economically justified way. The small increase of the system price by providing the measuring smart sensors, already equipped some element of control or computation, with radio communication assures the decrease of measurement errors and makes the collection of environmental data convenient for the system operator.
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Et. al., Kiranmai Babburu ,. "PAPR REDUCTION TECHNIQUES AND IMAGE QUALITY ASSESSMENTIN IMAGE BASED MMS VLC SYSTEM". INFORMATION TECHNOLOGY IN INDUSTRY 9, n. 2 (13 aprile 2021): 1178–85. http://dx.doi.org/10.17762/itii.v9i2.469.
Testo completoAbstract (sommario):
The radiofrequency method of transmission suffers from the problem of the limited licensed radio frequency spectrum, & security, wide EMI (electromagnetic interference), high multipath fading & power consumption for short-range applications. The solution to these problems can be achieved by using optical wireless communication technique called the Visible Light Communication system where the data is sent through regulated emission of light. The transmission of digital image information productively in the present optical wireless communication framework is an uphill task as these systems often suffer from problems like frequency selective fading propagation losses and inter-symbol interferences. In order to conquer such difficulties we hereby propose a robust method to transfer the digital image through a Multi-Carrier Modulation Scheme-MMS. In this paper, an Image-Based Multicarrier modulation VLC system is designed through which is sent a corrupted Digital Image with additive white Gaussian noise and explored the overall execution of the Image based Multicarrier modulation VLC system at distinct SNR values. The paper also addresses the issue of high Peak to Average Power Ratio (PAPR) in Multicarrier modulation and reduced it by using different PAPR reduction techniques. The received image quality of the proposed system is obtained under different signal to noise ratios at different modulation schemes..
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Aameer Ibrahim, Isam, e Tahreer Safa’a Mansour. "Study and Simulation of Transporting Radio Frequency Signals over Free Space Optics for Achieving High Data Rate and Power Saving". International Journal of Interactive Mobile Technologies (iJIM) 15, n. 16 (23 agosto 2021): 79. http://dx.doi.org/10.3991/ijim.v15i16.24189.
Testo completoAbstract (sommario):
The remarkable technology for seamless integration of wireless and optical networks is radio frequency signals over Free Space Optics (FSO). This research study and simulation examine the design and evaluation performance of Radio Frequency over FSO (RF-FSO) wireless communication technology. These systems are implemented through medium communication link ranges to overcome excessive sensitivity of atmosphere medium and meet the requirements of a wide variety of optical wireless applications. There are two ways to achieve the application of the design mentioned above. The first way is the application of the Three modulation schemes of technology that is Amplitude shift keying (ASK), Quadrature amplitude modulation (QAM), and Quadrature phase-shift keying (QPSK) of digital modulation. The design of these modulation schemes is realized by using optiwave software to study the transmission of RF signals over the FSO channel and compare the three modulation techniques into the RF-FSO system. RF signals with the frequency range from (20 to 60) GHz is used in RF-FSO system and many carrier optical signals where the higher RF has a wider bandwidth to carrying larger information. To increase the transmission of data rates Wavelength Division Multiplexing (WDM) technology is used. The second way is based on a mathematical model which has been proposed for this study. This mathematical model calculates optimal beacon period (BI), and optimal listen interval (LI) to preventing the overlapping of time between the signals and the decrease in the required power. Using different weather conditions samples, the simulation results revealed that the best performance of the RF-FSO system is from link range, and the receiver is more sensitive. The simulation results are as follows: Two independent channels are transmitted 20 Gbps over ranges from (263 m to 6.55 km), while four channels are transmitted 40 Gbps over ranges from (257 m to 5.95 km), and eight independent channels transmit 80 Gbps over distance from (203 m to 5.2 km)
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Marriwala, Nikhil, O. P. Sahu e Anil Vohra. "Performance Analysis of Multiple FEC Channel Coding Algorithms for Software Defined Radio Using Quadrature Amplitude Modulation". International Journal of Applied Metaheuristic Computing 7, n. 2 (aprile 2016): 1–15. http://dx.doi.org/10.4018/ijamc.2016040101.
Testo completoAbstract (sommario):
This paper describes the development of a Software Defined Radio (SDR)-based Transceiver simulation model using Quadrature Amplitude Modulation (QAM) Scheme and analyze its performance using Forward Error Correction (FEC) channel coding algorithms namely the Convolution and the Turbo Codes. This model efficiently evaluates the performance of high data rate multi array M-QAM, schemes. The performance of these FEC codes is evaluated when the system is subjected to noise and interference in the channel. In this design Additive White Gaussian Noise (AWGN) channel has been considered. The design is analyzed using Bit Error Rate (BER) and Signal to Noise Ratio (SNR) for different M-QAM techniques. The simulation results give a possible solution for future SDR systems which may be used in various wireless communication systems. An experimental result shows that the QAM transceiver achieves the transmission of data at high level accurately. FEC Channel coding scheme is used wherever the re-transmission of the data is not feasible. On the receiver side, this channel coded signal is decoded in order to get back the original data even if the channel coded signal undergoes some interference from the noise in the transmission medium. The Performance is then analyzed in terms of BER for Convolution Coding and Turbo Coding algorithm at a particular value of SNR in LabVIEW graphical programming. Finally, comparison has been drawn based on different parameters between the existing SDR system and the proposed design in this paper to analyze and highlight the effectiveness of the proposed SDR design.