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Adaptation of Propagation Models to Improve the Coverage Range Prediction of LoRaWAN Technology at 915 MHz in an Urban Environment

Suarez-Suare Carlos René, Rueda Diego F, Timaná-Eraso Luis Carlo, Leon-Leon Jose

International Journal of Electronics and Telecommunications

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2023

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Vol. 69, No. 4

733--744

EN

Long Range Wide Area Network (LoRaWAN) technology has established new concepts for long-range wireless communication, being widely used in the implementation of IoT solutions. Therefore, it is crucial to validate the coverage of the signal and to know the distance at which a LoRAWAN communication system can be connected. This document investigates LoRaWAN technology for cases based on urban environments, so it can be used as a guide for those projects that require predicting the connection distance range of a LoRaWAN link. In addition, it serves as a tool for the reader when it comes to predicting the coverage of Long-Range Wide Area Network (LoRaWAN) technology. Measurements were made in a LoRaWAN network deployed in urban environments, where RSSI measurements were made in the city of Bogotá D.C., Colombia. Experimentally RSSI values were compared with four different propagation models at a frequency of 915 MHz in urban environments. The contribution of this work is an adjustment to widely used prediction models, according to the recommendation of the International Telecommunications Union (ITU) ITU-R P.1546, which allows estimating coverage in scenarios with characteristics similar to Bogotá D.C. This allows to know with precision the coverage before implementing the LoRaWAN communications system at 915 MHz. The results of comparing field measurements with fitted propagation models show that the Okumura model is the best predictor of coverage with a minimum error rate.

2

An Optimized Propagation Model based on Measurement Data for Indoor Environments

Morocho-Yaguana M., Ludeňa-González P., Sandoval F., Poma-Vélez B., Erreyes-Dota A.

Journal of Telecommunications and Information Technology

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2018

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nr 2

69--75

EN

Propagation is an essential factor ensuring good coverage of wireless communications systems. Propagation models are used to predict losses in the path between transmitter and receiver nodes. They are usually deﬁned for general conditions. Therefore, their results are not always adapted to the behavior of real signals in a speciﬁc environment. The main goal of this work is to propose a new model adjusting the loss coeﬃcients based on empirical data, which can be applied in an indoor university campus environment. The Oneslope, Log-distance and ITU models are described to provide a mathematical base. An extensive measurement campaign is performed based on a strict methodology considering different cases in typical indoor scenarios. New loss parameter values are deﬁned to adjust the mathematical model to the behavior of real signals in the campus environment. The experimental results show that the model proposed oﬀers an attenuation average error of 2.5% with respect to the losses measured. In addition, comparison of the proposed model with existing solutions shows that it decreases the average error signiﬁcantly for all scenarios under evaluation.

3

A workflow-oriented approach to Propagation Models in Heliophysics

Pierantoni G., Carley E., Byrne J., Perez-Suarez D., Gallagher P. T.

Computer Science

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2014

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Vol. 15 (3)

271--291

EN

The Sun is responsible for the eruption of billions of tons of plasma and the generation of near light-speed particles that propagate throughout the solar system and beyond. If directed towards Earth, these events can be damaging to our tecnological infrastructure. Hence there is an effort to understand the cause of the eruptive events and how they propagate from Sun to Earth. However, the physics governing their propagation is not well understood, so there is a need to develop a theoretical description of their propagation, known as a Propagation Model, in order to predict when they may impact Earth. It is often difficult to define a single propagation model that correctly describes the physics of solar eruptive events, and even more difficult to implement models capable of catering for all these complexities and to validate them using real observational data. In this paper, we envisage that workflows offer both a theoretical and practical framework for a novel approach to propagation models. We define a mathematical framework that aims at encompassing the different modalities with which workflows can be used, and provide a set of generic building blocks written in the TAVERNA workflow language that users can use to build their own propagation models. Finally we test both the theoretical model and the composite building blocks of the workflow with a real Science Use Case that was discussed during the 4th CDAW (Coordinated Data Analysis Workshop) event held by the HELIO project. We show that generic workflow building blocks can be used to construct a propagation model that succesfully describes the transit of solar eruptive events toward Earth and predict a correct Earth-impact time.

4

Extending the sheba propagatio model to reduce parameter-related uncertainties

Pierantoni G., Coghlan B., Kenny E., Gallagher P., Perez-Suarez D.

Computer Science

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2013

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Vol. 14 (2)

253--272

EN

Heliophysics is the branch of physics that investigates the interactions and correlation of different events across the Solar System. The mathematical models that describe and predict how physical events move across the solar system (ie. Propagation Models ) are of great relevance. These models depend on parameters that users must set, hence the ability to correctly set the values is key to reliable simulations. Traditionally, parameter values can be inferred from data either at the source (the Sun) or arrival point (the target) or can be extrapolated from common knowledge of the event under investigation. Another way of setting parameters for Propagation Models is proposed here: instead of guessing a priori parameters from scientific data or common knowledge, the model is executed as a parameter-sweep job and selects a posteriori the parameters that yield results most compatible with the event data. In either case ( a priori and a posteriori ), the correct use of Propagation Models requires information to either select the parameters, validate the results, or both. In order to do so, it is necessary to access sources of information. For this task, the HELIO project proves very effective as it offers the most comprehensive integrated information system in this domain and provides access and coordination to services to mine and analyze data. HELIO also provides a Propagation Model called SHEBA, the extension of which is currently being developed within the SCI-BUS project (a coordinated effort for the development of a framework capable of offering to science gateways seamless access to major computing and data infrastructures).

5

Budowa sieci DVB-H na obszarach zabudowanych z wykorzystaniem sieci TV kablowej

Szóstka J.

Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne

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2011

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nr 1

32-34

PL

Przedstawiono koncepcję wykorzystania sieci TV kablowej jako sieci dosyłowej sygnału dla gęstych sieci SFN DVB-H z nadajnikami o małej mocy w obszarach miejskich. Przedstawiono też wyniki testów jakości sygnału oraz wyniki pomiarów propagacyjnych w środowisku miejskim. Proponowane rozwiązanie jest konkurencyjne w porównaniu z tradycyjnymi sieciami DVB-H, dzięki krótkiemu czasowi budowy, lepszym zasięgom wewnątrz budynków oraz kosztom.

EN

The article presents the concept of using a cable TV (CATV) network as a signal distribution network for dense DVB-H SFN networks with low-power transmitters in urban areas. The results of signal quality tests are also presented as well as the results of propagation tests in the urban environment. The proposed solution is competitive with traditional DVB-H networks thanks to the time of network development, better indoor coverage and costs.

6

Szerokopasmowa metoda badania propagacji fal elektromagnetycznych w podziemnych wyrobiskach górniczych

Worek C.

Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne

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2009

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nr 10

1952-1954

PL

Przedstawiono nowatorską metodę badania propagacji fal elektromagnetycznych w szerokim zakresie częstotliwości, która została przetestowana w podziemnych wyrobiskach górniczych. W układzie pomiarowym wykorzystano generator szumu dużej mocy, szerokopasmowe anteny nadawcze oraz szerokopasmową aktywną sondę o znanych współczynnika antenowych i analizator widma. Uzyskano znaczne skrócenie czasu pomiarów przy jednoczesnym otrzymaniu wyników w szerokim zakresie częstotliwości (od 30MHz do 1000MHz). Zaletą przedstawionej metody jest otrzymanie wyników w bezwzględnych jednostkach natężenia pola elektrycznego V/m, co umożliwia testowanie i weryfikację modeli propagacyjnych opracowanych teoretycznie lub też za pomocą specjalistycznego oprogramowania. Metodę tę wykorzystano w badaniach propagacji fal elektromagnetycznych w podziemnych korytarzach w KWK Ziemowit, a uzyskane wyniki porównano z danymi literaturowymi.

EN

The paper presents a novel method for analysis of electromagnetic waves propagation in wide frequency range, which has been tested experimentally in underground mine tunnels. The measuring system utilizes a high-power noise generator, wideband transmitting antennas, a wideband active probe with known antenna factors and spectrum analyser. This configuration enabled significant reduction in measurement time, as well as obtaining the measurement results in wide frequency range (30MHz to 1000MHz). An additional advantage of the presented method is its capability to obtain results expressed in absolute units of electric field strength V/m what in turn, enables testing and verification of propagation models developed either theoretically or by means of specialized software. The developed method has been employed for investigation of electromagnetic waves propagation in underground tunnels of the Ziemowit coal mine, and the results have been compared with the literature data.

7

Wspomaganie projektowania sieci WLAN

Maciaszczyk R., Bembnista K.

Metody Informatyki Stosowanej

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2009

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nr 4 (21)

63-71

EN

The paper describes the application to support design the WLAN wireless networks. The system that was worked out enables to taking measurements with Wi-Fi card use and determining position using GPS receiver or doing it manually. Gathered data can be subjected to Krige 's interpolation. Thanks to it a map of network 's coverage can be created. Moreover, this program allows to making simulations of microwaves propagation using Free Space Path Loss model or Multi Wall model which considers obstacles' influence, being on a direct propagation path connecting access point with a station, on signal strength. Comparison of Free Space Path Lass model and Multi Wall model calculations with measurement's results was collated.

8

Projektowanie sieci bezprzewodowych WLAN i WPAN wewnątrz budynków - modele propagacyjne

Krzysztofik W., Horbatowski P.

Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne

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2007

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nr 7

221-231

PL

Przedstawiono modele propagacyjne najczęściej wykorzystywane do projektowania bezprzewodowych sieci komputerowych WLAN i WPAN wewnątrz budynków. Zaprezentowano komercyjne lub uniwersyteckie programy komputerowe wspomagające projektowanie sieci WLAN i WPAN.

EN

Paper presents propagation models usefull for designing wireless systems WLAN and WPAN inside the buildings. The examples of commercial and academic computer codes are introduced.