scholarly journals Outdoor radiolinks for 2.4 GHz-frequencies: measurement results and experiences within the radio communication network “Intermobil Region Dresden"

2003 ◽  
Vol 1 ◽  
pp. 301-307
Author(s):  
O. Michler
Keyword(s):  
Communication Network ◽  
Communication Networks ◽  
Fresnel Zone ◽  
Multipath Propagation ◽  
Radio Channel ◽  
Path Loss ◽  
Radio Communication ◽  
Technical Parameters ◽  
Measurement Results ◽  
Technical Solutions

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.

scholarly journals Performance of Base Stations in Railway Digital Radio Communication Networks

2021 ◽  
Vol 19 (2) ◽  
pp. 41-48
Author(s):  
Yu. V. Nemtsov ◽  
I. V. Seryogin ◽  
P. I. Volnov
Keyword(s):  
Communication Network ◽  
Communication Networks ◽  
Base Station ◽  
Base Stations ◽  
Radio Communication ◽  
Radio Communications ◽  
Digital Radio ◽  
Cargo Transportation ◽  
Assess Quality

Base station (BS) is a terminal device of a radio communication network, while railway radio communications play an important role in ensuring safety of passenger and cargo transportation.A proposed method for calculating the performance of base stations in railway digital radio communication networks is intended to calculate for the BS the probabilities of being in certain state.BS was decomposed and such functional elements as circuit groups and a radio frequency path were identified, as well as the central module ensuring the exchange of information with elements of this BS and with other BSs. A detailed study of each element has increased accuracy of the proposed method. Following the Markov model, BS is presented as a system in which all possible states are considered. Models for BS with two and three circuit groups have been constructed. The parameters of each functional element of the model can be obtained through observation over a certain period. The solution of the system of equations for each of the models presented in the article will allow obtaining the values of the system being in a certain state. The obtained characteristics can be used to calculate the reliability of the entire radio communication network, and then to assess quality of service provided to the users of this network.Conclusions are made about the possibilities of using the obtained models when designing new railway communication networks and when calculating quality indices of existing ones. The proposed models can be applied not only to railway radio communication networks but also to mobile communication networks of commercial operators. 

scholarly journals On the assessment of the reliability of the train radio communication channel

2021 ◽  
Vol 2131 (4) ◽  
pp. 042096
Author(s):  
D N Roenkov ◽  
P A Plekhanov
Keyword(s):  
Communication Networks ◽  
Communication Channel ◽  
Radio Channel ◽  
Point Of View ◽  
Radio Station ◽  
Calculation Formula ◽  
Radio Communication ◽  
Communication Reliability ◽  
Radio Communication System ◽  
Mobile Subscriber

Abstract The research purposeis to develop an approach to assessing the reliability of a train radio communication channel based on the representation of a radio communication network in the form of a model that includes both traditional elements (various types of equipment, a wire channel) and a radio channel, which is proposed to be described by the availability of radio coverage, which varies depending on the location of the mobile subscriber. In the research methods of the theory of reliability, and, in particular, the assessment of the availability factor of the elements of the radio communication system and communication channels, dynamically changing during the movement of the mobile radio station. In addition, to assess the energy of radio channels, the theory of radio wave propagation was applied, including on the basis of industry recommendations for calculating radio communication networks of JSC Russian Railways. As result of the research, a method was proposed for assessing the dependence of the reliability of a train radio communication channel (in terms of readiness) on the track coordinate. In this case, the radio communication channel dynamically changes the composition of the elements when the mobile subscriber moves along the railway section. Simultaneously, for each point of the section, the calculation formula is also dynamically changed, which makes it possible to find the value of the readiness of the communication channel. The proposed approach allows to identify the sections of technological radio communication networks that are weakest from the point of view of communication reliability and take this information into account when planning work to improve the reliability of communication networks.

scholarly journals Narrowband Characterization of Near-Ground Radio Channel for Wireless Sensors Networks at 5G-IoT Bands

Sensors ◽  
2018 ◽  
Vol 18 (8) ◽  
pp. 2428 ◽  
Author(s):  
Hicham Klaina ◽  
Ana Vazquez Alejos ◽  
Otman Aghzout ◽  
Francisco Falcone
Keyword(s):  
Channel Model ◽  
Fresnel Zone ◽  
Radio Channel ◽  
Path Loss ◽  
Link Quality ◽  
Sensor Nodes ◽  
Radio Link ◽  
Tall Grass ◽  
Received Power ◽  
Log Normal

In this contribution, a narrowband radio channel model is proposed for rural scenarios in which the radio link operates under near-ground conditions for application in wireless sensor networks dedicated to smart agriculture. The received power attenuation was measured for both transmitter and receiver antennas placed at two different heights above ground: 0.2 and 0.4 m. Three frequency ranges, proposed for future 5G-IoT use case in agriculture, were chosen: 868 MHz, 2.4 GHz and 5.8 GHz. Three ground coverings were tested in a rural scenario: soil, short and tall grass fields. The path loss was then estimated as dependent of the radio link range and a three-slope log-normal path loss model was tailored. Results are explained in terms of the first Fresnel zone obstruction. Commercial Zigbee sensor nodes operating at 2.4 GHz were used in a second experiment to estimate the link quality from the experimental Radio Signal Strength Indicator (RSSI) received values. Two sensor nodes were placed at the same elevation above ground as in the previous experiment, only for short grass field case. The Quality of Service performance was determined in terms of theoretical bit error rate achieved for different digital modulations—BPSK, 8PSK and 16QAM—concluding remarkable results for an obstructed radio link.

scholarly journals Radio Channel Characterization in Dense Forest Environments for IoT-5G

Proceedings ◽  
2018 ◽  
Vol 4 (1) ◽  
pp. 19
Author(s):  
Peio Lopez-Iturri ◽  
Erik Aguirre ◽  
Mikel Celaya-Echarri ◽  
Leyre Azpilicueta ◽  
Alejandro Eguizábal ◽  
...  
Keyword(s):  
Communication Systems ◽  
Channel Model ◽  
Multipath Propagation ◽  
Radio Channel ◽  
Path Loss ◽  
Simulation Software ◽  
Delay Spread ◽  
Radio Link ◽  
Zone Model ◽  
Dense Forest

The attenuation due to vegetation can limit drastically the performance of Wireless Sensor Networks (WSN) and the Internet of Things (IoT) communication systems. Even more for the envisaged high data rates expected for the upcoming 5G mobile wireless communications. In this context, radio planning tasks become necessary in order to assess the validity of future WSN and IoT systems operating in vegetation environments. For that purpose, path loss models for scenarios with vegetation play a key role since they provide RF power estimations that allow an optimized design and performance of the wireless network. Although different propagation models for vegetation obstacles can be found in the literature, a model combining path loss and multipath propagation is rarely considered. In this contribution, we present the characterization of the radio channel for IoT and 5G systems working at 2.4 GHz, focusing on the radio links blocked by oak and pine trees modelled from specimens found in a real recreation area located within a dense forest environment. This specific forest, composed of thick in-leaf trees, is called Orgi Forest and it is situated in Navarre, Spain. In order to fit and validate a radio channel model for this type of scenarios, both measurements and simulations by means of an in-house developed 3D Ray Launching algorithm have been performed, offers as outcomes the path loss and multipath information of the scenario under study. A geometrical and dielectric model of the trees were created and introduced in the simulation software. The path loss was then estimated as dependent of the radio link range for two species of trees at 2.4 GHz. We concluded that the scattering produced by the tree can be divided into two zones with different dominant propagation mechanisms: a free-space zone far from the tree and a diffraction zone around the edge of the tree. 2D planes of delay spread value are also presented which similarly reflects the proposed two-zone model.

scholarly journals INCREASE OF EFFICIENCY OF SUPPRESSION OF THE ACTIVE NOISE JAMMING IN RADAR INTERCEPTION OF AIR TARGETS IN THE REVIEW MODE

2017 ◽  
pp. 57-68
Author(s):  
V. E. Markevich
Keyword(s):  
Mathematical Modeling ◽  
Covariance Matrix ◽  
Multipath Propagation ◽  
Antenna System ◽  
Radio Communication ◽  
Matrix Estimation ◽  
Technical Parameters ◽  
Active Noise ◽  
Inverse Covariance Matrix ◽  
Self Tuning

The modified algorithm of the adaptive compensating of the active noise jamming, based on usage of the recurrence estimation of inverse covariance matrix of jamming in the course of an self-tuning is considered. The matrix estimation is formed by a method of a serial regression (SRM), a consequence application of a lemma about inversing of a matrix to differential – to the difference equation for a rounded estimation of direct covariance matrix of jamming (CMJ). The single estimation of straight line CMJ is formed as result dyad products of the instant vectors of noises in handling channels. In partial channels the adaptive transversal filters with the self-tuning on value of a signal of an aggregate error are implemented.In article skeleton diagrams of devices of the compensating implemented by various methods are resulted. Mathematical modeling of operation of the algorithms, implemented by a method of the least squares (criterion of a minimum RMS error) and a method of a serial regression is performed.Results of mathematical modeling of operation of the device of compensating of active noises jamming in the conditions of the active radio-electronic counteraction at multipath propagation of signals both non-identical amplitude and phase characteristics of channels of handling are resulted. Optimal values of technical parameters of devices of compensating of the active noises jamming providing obtaining of demanded values of coefficient of suppression are given. The comparative analysis of indexes of efficiency of classical and offered algorithms of compensating is made. Advantage of algorithm of compensating of the active noises jamming, using the recurrence estimation of a inverse covariance matrix of jamming is shown.The algorithm of functioning on the basis of SRM allows to lower essentially requirements to specialized VLSI (FPGA) at implementation is hardware – program complexes for preprocessing of the radar, radio communication and radio – navigation information in the conditions of influence of the active noises jamming in the presence of effects of multipath propagation of signals, in the presence of delay of signals on an antenna system aperture, and also at unremovable technological dispersion amplitude and phase characteristics of the microwave of channels of handling.

scholarly journals Deterministic and Empirical Approach for Millimeter-Wave Complex Outdoor Smart Parking Solution Deployments

Sensors ◽  
2021 ◽  
Vol 21 (12) ◽  
pp. 4112
Author(s):  
Fidel Alejandro Rodríguez-Corbo ◽  
Leyre Azpilicueta ◽  
Mikel Celaya-Echarri ◽  
Peio Lopez-Iturri ◽  
Ana V. Alejos ◽  
...  
Keyword(s):  
Large Scale ◽  
Radio Channel ◽  
Path Loss ◽  
Ground Level ◽  
Directional Antennas ◽  
Scale Parameters ◽  
Parking Lot ◽  
Smart Parking ◽  
Wireless Communications Systems

The characterization of different vegetation/vehicle densities and their corresponding effects on large-scale channel parameters such as path loss can provide important information during the deployment of wireless communications systems under outdoor conditions. In this work, a deterministic analysis based on ray-launching (RL) simulation and empirical measurements for vehicle-to-infrastructure (V2I) communications for outdoor parking environments and smart parking solutions is presented. The study was carried out at a frequency of 28 GHz using directional antennas, with the transmitter raised above ground level under realistic use case conditions. Different radio channel impairments were weighed in, considering the progressive effect of first, the density of an incremental obstructed barrier of trees, and the effect of different parked vehicle densities within the parking lot. On the basis of these scenarios, large-scale parameters and temporal dispersion characteristics were obtained, and the effect of vegetation/vehicle density changes was assessed. The characterization of propagation impairments that different vegetation/vehicle densities can impose onto the wireless radio channel in the millimeter frequency range was performed. Finally, the results obtained in this research can aid communication deployment in outdoor parking conditions.

RUSSIAN MARKET OF PROFESSIONAL MOBILE RADIO AND CRITICAL COMMUNICATIONS: CURRENT STATE, PROBLEMS, PROSPECTS

2021 ◽  
Author(s):  
О.А. ШОРИН ◽  
Р.Ю. КАСПАРИ
Keyword(s):  
Information Transmission ◽  
Communication Networks ◽  
Communication Technology ◽  
Mobile Radio ◽  
Radio Communication ◽  
Russian Market ◽  
Critical Information ◽  
Current State ◽  
Telecommunications Market

Рассмотрены характеристики и аудитория сетей профессиональной радиосвязи и критических коммуникаций. Проведен анализ используемых в России технологий профессиональной радиосвязи и перспектив развития данного сегмента телекоммуникационного рынка, произведена оценка его объемов в пятилетней перспективе. Показано, что внедряемая технология широкополосной профессиональной связи МАКВИЛ не только решает назревшие проблемы, связанные с модернизацией морально и физически устаревших систем ведомственной и корпоративной транкинговой связи, но и открывает новые возможности роста рынка услуг передачи критически важной информации. The characteristics and audience of professional mobile radio and critical communication networks are reviewed. The analysis of professional mobile radio technologies used in Russia and the prospects for the development of this segment of the telecommunications market is carried out, as well as its volume is estimated in the five-year perspective. It is shown that McWiLL broadband professional radio communication technology not only solves the urgent problems associated with the modernization of morally and physically obsolete systems of departmental and corporate trunking communications, but also opens up new opportunities for the growth of the market for critical information transmission services.

scholarly journals Cooperative Problem Solving in Telecommunication Network

2013 ◽  
Vol 4 (3) ◽  
pp. 388-392
Author(s):  
Shanu K Rakesh ◽  
Bharat Choudhary ◽  
Rachna Sandhu
Keyword(s):  
Communication Network ◽  
Problem Solving ◽  
Distributed Control ◽  
Communication Networks ◽  
Foraging Behaviour ◽  
Telecommunication Network ◽  
Telecommunication Networks ◽  
Control Problems ◽  
Engineering Systems ◽  
Biologically Inspired

Swarm intelligence, as demonstrated by natural biological swarms, has numerous powerful properties desirable in many engineering systems, such as telecommunication. Communication network management is becoming increasingly difficult  due to the increasing size, rapidly changing topology, and complexity of communication networks. This paper describes  how biologically-inspired agents can be used to solve control problems in telecommunications. These agents, inspired by the foraging behaviour of ants, exhibit the desirable characteristics of simplicity of action and interaction. The colle ction of agents, or swarm system, deals only with local knowledge and exhibits a form of distributed control with agent communication effected through the environment. In this paper we explore the application of ant-like agents to the problem of routing in telecommunication networks.

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