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Journal articles on the topic 'Outdoor path loss models'
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Abdullah, Saifuddin, and Dr Fuad Al-Najjar. "A Collective Statistical Analysis of Outdoor Path Loss Models." INTERNATIONAL JOURNAL OF COMPUTERS & TECHNOLOGY 3, no. 1 (2012): 6–10. http://dx.doi.org/10.24297/ijct.v3i1a.2720.
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This study encompasses nine path loss models (Erceg-Greenstein, Green-Obaidat, COST Hata, Hata Urban, Hata Rural, Hata Suburban, SUI, Egli and ECC-33) which were programmed on Python and studied for their results in an urban architecture (translated by higher attenuation variables) at 950 MHz and 1800 MHz. The results obtained showed that increasing the transmission antenna height with the increasing distance not only lowers down the path loss readings, but also shows that the standard deviation between the results of studied path loss models increases with the increasing transmission antenna height and increasing distance at both 950 MHz and 1800 MHz systems, especially when transmission antenna height crosses the GSM standard of 40 meters and cell-radius exceeds the limit of 20 kilometers. Moreover, it is also observed that at both 950 MHz and 1800 MHz, the path loss readings of all the models disperse from their collective mean between 1 and 10 Km, but tend converge afterwards (i.e. from 10 to 40 Km and onwards) towards their mean, which indicates that path loss readings of the urban models tend to follow either a single convergence point on large distances or reach their maximum threshold level (a level from which their readings cannot exceed or differ from each other significantly).
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Samimi, Mathew K., Theodore S. Rappaport, and George R. MacCartney. "Probabilistic Omnidirectional Path Loss Models for Millimeter-Wave Outdoor Communications." IEEE Wireless Communications Letters 4, no. 4 (2015): 357–60. http://dx.doi.org/10.1109/lwc.2015.2417559.
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Bian, Chengzhen, Weiping Li, Mingxu Wang, Xinyi Wang, Yi Wei, and Wen Zhou. "Path Loss Measurement of Outdoor Wireless Channel in D-band." Sensors 22, no. 24 (2022): 9734. http://dx.doi.org/10.3390/s22249734.
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D-band (110–170 GHz) has received much attention in recent years due to its larger bandwidth. However, analyzing the loss characteristics of the wireless channel is very complicated at the millimeter-wave (MMW) band. Research on D-band wireless channels has been focused on indoor short-distance transmissions, with few studies looking at outdoor long-distance wireless channels. In this paper, we provide the design of the D-band outdoor long-distance transmission system, propose the outdoor line-of-sight (LOS) propagation measurements, and study the outdoor D-band propagation loss characteristics with distances up to 800 m. The path loss model uses the Floating Intercept (FI) and the Close-In (CI) model is established based on the least square method. In the CI model, the path loss exponent is greater than 2 and increases with frequency, while in the FI model, the path loss exponent has no apparent frequency dependence. The results show that D-band path loss in long-distance outdoor scenarios is greater than that in free space, indicating that the propagation condition is worse than in free space. The results show that both models have similar performance. Under this basis, the model with the smallest number of parameters would be the optimal choice. In addition, these results prospectively provide a theoretical model for designing and optimizing high frequency mm-wave propagation measurements at a distance of 200 m and beyond.
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Shalaby, Abdulrahman M., and Noor Shamsiah Othman. "The Effect of Rainfall on the UAV Placement for 5G Spectrum in Malaysia." Electronics 11, no. 5 (2022): 681. http://dx.doi.org/10.3390/electronics11050681.
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In this paper, the influence of rainfall on the deployment of UAV as an aerial base station in the Malaysia 5G network is studied. The outdoor-to-outdoor and outdoor-to-indoor path loss models are derived by considering the user’s antenna height, rain attenuation, and the wall penetration loss at high frequencies. The problem of finding the UAV 3D placement is formulated with the objective to minimize the total path loss between the UAV and all users. The problem is solved by invoking two algorithms, namely Particle Swarm Optimization (PSO) and Gradient Descent (GD) algorithms. The performance of the proposed algorithms is evaluated by considering two scenarios to determine the optimum location of the UAV, namely outdoor-to-outdoor and outdoor-to-indoor scenarios. The simulation results show that, for the outdoor-to-outdoor scenario, both algorithms resulted in similar UAV 3D placement unlike for the outdoor-to-indoor scenario. Additionally, in both scenarios, the proposed algorithm that invokes PSO requires less iterations to converge to the minimum transmit power compared to that of the algorithm that invokes GD. Moreover, it is also observed that the rain attenuation increases the total path loss for high operating frequencies, namely at 24.9 GHz and 28.1 GHz. Hence, this resulted in an increase of UAV required transmit power. At 28.1 GHz, the presence of rain at the rate of 250 mm/h resulted in an increase of UAV required transmit power by a factor of 4 and 15 for outdoor-to-outdoor and outdoor-to-indoor scenarios, respectively.
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Alex, Akohoule, Bamba Aliou, Kamagate Aladji, Konate Adama, Oussama Tabbabi, and Asseu Olivier. "MEASUREMENTSBASEDEVALUATION OF PATHLOSSEXPONENTS IN URBAN OUTDOORENVIRONMENTS." International Journal of Advanced Research 9, no. 03 (2021): 72–79. http://dx.doi.org/10.21474/ijar01/12556.
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In wireless networks, propagation models are used to assess the received power signal and estimate the propagation channel. These models depend on the pathloss exponent (PLE) which is one of the main parameters to characterize the propagation environment. Indeed, in the wireless channel, the path loss exponent has a strong impact on the quality of the links and must therefore be estimated with precision for an efficient design and operation of the wireless network. This paper addresses the issue of path loss exponents estimation for mobile networks in four outdoor environments. This study is based on measurements carried out in four outdoor environments at the frequency of 2600 MHz within a bandwidth of 70 MHz. It evaluates the path loss exponent, and the impact of obstacles present in the environments. The parameters of the propagation model determined from the measurements show that the average power of the received signal decreases logarithmically with the distance. We obtained path loss exponents values of 4.8, 3.53, 3.6 and 3.99 for the site 1, site 2, site 3 and site 4, respectively. Clearly the density of the obstacles has an impact on the path loss exponents and our study shows that the received signal decrease faster as the transmitter and receiver separation in the dense environments.
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Jimoh, AKAANNI, ISA Abdurrhaman Ademola, OGUNBIYI Olalekan, OLUFEAGBA Benjamin. Jimmy, and SANNI Tunde Abdulrahman. "AJ-Olu-1: An Innovative Path Loss Model for Typical Nigerian Urban Environments." KIU Journal of Science, Engineering and Technology 2, no. 1 (2023): 17–23. http://dx.doi.org/10.59568/kjset-2023-2-1-03.
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The modeling of outdoor path loss propagation is critical in the planning and construction of the Global System for Mobile Communication (GSM) coverage area. For GSM signal prediction at any location inside its service region, a precise forecast based on critical characteristics and a mathematical model is required. Numerous research findings on path loss propagation model forecast for GSM mobile networks conducted in various cities in Nigeria revealed that the COST231-Hata model gives closer prediction to most of the practical measure path loss values. Based on the existing COST-23-Hata path loss model and outdoor measurements at 1800 MHz frequency range within Ilorin metropolis, this paper proposed a suitable path loss model. The developed model was used and validated in various locations throughout Ilorin city with the measured and COST-231 Hata models. The analysis of the results revealed that the developed model performed satisfactorily in terms of the closest path loss prediction to the practical measure path loss values at all study locations. It also has the lowest Square Root Means Error and Standard Deviation (SD) of any Base Station (BTS) tested in Ilorin, Nigeria. As a result, it is concluded that the newly developed AJ-Olu-1 model is more suitable for GSM 1800 network design and installation in Ilorin City, Nigeria, as well as other cities in Nigeria and other cities outside Nigeria with similar environments.
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Al-Samman, Ahmed, Tharek Rahman, MHD Hindia, Abdusalama Daho, and Effariza Hanafi. "Path Loss Model for Outdoor Parking Environments at 28 GHz and 38 GHz for 5G Wireless Networks." Symmetry 10, no. 12 (2018): 672. http://dx.doi.org/10.3390/sym10120672.
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It has been widely speculated that the performance of the next generation Internet of Things (IoT) based wireless network should meet a transmission speed on the order of 1000 times more than current wireless networks; energy consumption on the order of 10 times less and access delay of less than 1 ns that will be provided by future 5G systems. To increase the current mobile broadband capacity in future 5G systems, the millimeter wave (mmWave) band will be used with huge amounts of bandwidth available in this band. Hence, to support this wider bandwith at the mmWave band, new radio access technology (RAT) should be provided for 5G systems. The new RAT with symmetry design for downlink and uplink should support different scenarios such as device to device (D2D) and multi-hop communications. This paper presents the path loss models in parking lot environment which represents the multi-end users for future 5G applications. To completely assess the typical performance of 5G wireless network systems across these different frequency bands, it is necessary to develop path loss (PL) models across these wide frequency ranges. The short wavelength of the highest frequency bands provides many scatterings from different objects. Cars and other objects are some examples of scatterings, which represent a critical issue at millimeter-wave bands. This paper presents the large-scale propagation characteristics for millimeter-wave in a parking lot environment. A new physical-based path loss model for parking lots is proposed. The path loss was investigated based on different models. The measurement was conducted at 28 GHz and 38 GHz frequencies for different scenarios. Results showed that the path loss exponent values were approximately identical at 28 GHz and 38 GHz for different scenarios of parking lots. It was found that the proposed compensation factor varied between 10.6 dB and 23.1 dB and between 13.1 and 19.1 in 28 GHz and 38 GHz, respectively. The proposed path loss models showed that more compensation factors are required for more scattering objects, especially at 28 GHz.
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Akinbolati, Akinsanmi, Isah Shaibu, and Chidozie Okpala. "Investigation of Error Margin of Some Path Loss Models Over Digital Terrestrial Television Channel in Katsina Metropolis." Nigerian Journal of Theoretical and Environmental Physics 1, no. 1 (2024): 1–8. http://dx.doi.org/10.62292/njtep.v1i1.2023.11.
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Due to rapid development in mobile communication technology in recent times, strong signal coverage has become a major necessity. However, path loss is one of the major challenges against strong signal coverage. Several path loss models have been developed for predicting wireless signal coverage for urban, sub-urban and rural areas. However, the need to investigate which model can best predict losses in an environment becomes necessary. This work is aimed at comparing the Error Margin of some Path loss Models over Digital Terrestrial Television (DTTV) channel using the Star Times DTTV Channel within Katsina metropolis. Seven path loss predicting models for outdoor macro cell wireless communication were used. They are; Free Space model, COST-231 model, (developed by the European Union Co-operative for Scientific and Technical Research Team) Hata - Okurmura model, Plane Earth model, Okumura model, Ericson model and ECC model. The measurement campaigns were in two seasons, the wet season was in August and dry season in November, 2021. Both measured and predicted path loss values were computed using empirical models. Statistical error analysis based on the RMSE was carried out to determine the error margins between measured and predicted values. Based on the result of path loss assessment and error analysis, COST-231 with the lowest RMSE value of 13.49 dB which is within the acceptable range for sub-urban city is the most preferred amongst the investigated models for path loss prediction over digital UHF channel in Katsina city
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Israr, Imran, Mahmood Ashraf Khan, Shahzad A. Malik, Shahid A. Khan, and Mustafa Shakir. "Path Loss Modeling of WLAN and WiMAX Systems." International Journal of Electrical and Computer Engineering (IJECE) 5, no. 5 (2015): 1083. http://dx.doi.org/10.11591/ijece.v5i5.pp1083-1091.
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<p>With the advancement in technology, there was need for efficient and high speed internet through which we could have access to multiple networks as per the user requirement. WLAN met this need to some extent but, due to its low range it was not recommended commercially. With the introduction of WiMAX there was an emerging need to select the best network amongst WiMAX or WLAN depending upon the user location. Pathloss with respect to these particular networks also needs to be compared. In this paper we compare the pathloss modelling for WiMAX and WLAN systems. Different Models have been compared with each other to know which model performs better by keeping same simulation environment. Path Loss models used for WLAN are Okumura, Hata, Cost-231 and Free Space Path Loss whereas models used for WiMAX are Free Space Path Loss, Okumura-Hata, Cost231-Hata and Stanford University Interim. In case of WiMAX three different scenarios Urban, Sub-Urban and Rural is considered where as in case of WLAN only outdoor environment is considered. With the Path Loss comparison, power received for these two technologies; WiMAX, and WLAN is also simulated. MATLAB is the tool used for simulations. Antenna Specifications for WiMAX and WLAN is kept same for all simulation environments.</p>
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ARYANTA, DWI. "Analisis Prediksi Path Loss Teknologi Seluler 5G Pada Sel Micro Urban Wilayah Kota Bandung." ELKOMIKA: Jurnal Teknik Energi Elektrik, Teknik Telekomunikasi, & Teknik Elektronika 9, no. 3 (2021): 548. http://dx.doi.org/10.26760/elkomika.v9i3.548.
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ABSTRAKImplementasi teknologi seluler 5G di Indonesia perlu dilakukan kajian dalam beberapa aspek. Analisis nilai path loss pada sistem seluler merupakan pendekatan dalam aspek large scale fading untuk menghitung cakupan layanan. Penelitian ini melakukan kajian nilai path loss dengan mengambil kondisi di Kota Bandung dengan karakter sel urban mikro outdoor. Model prediksi yang digunakan pada kajian ini meliputi model SUI, ABG, CI, dan NYUSIM simulator menggunakan frekuensi kerja 3,5 GHz dan 28 GHz dengan lebar pita 100 MHz dan 800 MHz. Hasil pengujian memperlihatkan simulator NYUSIM memberikan nilai prediksi path loss yang paling mendekati nilai rata-rata path loss dengan nilai margin sebesar 1,25 dB untuk frekuensi 3,5 GHz dan 1,8 dB untuk frekuensi 28 GHz. Frekuensi kerja 28 GHz memiliki nilai path loss lebih tinggi dibandingkan frekuensi 3,5 MHz sebesar 19 dB. Nilai path loss pada kondisi LOS dan NLOS berdampak pada penurunan nilai path loss sebesar 35% pada frekuensi 3,5 GHz dan 26% pada frekuensi 28 GHz.Kata kunci: path loss, micro cell, urban, NYUSIM, LOS, NLOS ABSTRACTThe implementation of 5G cellular technology in Indonesia needs to be studied in several aspects. Analysis of the path loss value on the cellular system is an approach in the aspect of large scale fading to calculate service coverage. This research studies the path loss value by taking conditions in the city of Bandung with the character of outdoor micro urban cells. The prediction models used in this study include the SUI, ABG, CI, and NYUSIM simulators using working frequencies of 3.5 GHz and 28 GHz with a bandwidth of 100 MHz and 800 MHz. The test results show that the NYUSIM simulator provides a path loss prediction value that is closest to the average path loss value with a margin value of 1.25 dB for the 3.5 GHz frequency and 1.8 dB for the 28 GHz frequency. The 28 GHz working frequency has a path loss value higher than the 3.5 MHz frequency of 19 dB. The path loss value in LOS and NLOS conditions has an impact on reducing the path loss value by 35% at a frequency of 3.5 GHz and 26% at a frequency of 28 GHz.Keywords: path loss, micro cell, urban, NYUSIM, LOS, NLOS
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AKANNI, Jimoh, Ademola ISA Abdurrhaman, Olalekan OGUNBIYI, and Benjamin Jimmy OLUFEAGBA. "A modified cost-231-hata path loss model for typical semi-urban environments in Nigeria." KIU journal of science engineering and technology 3, no. 1 (2024): 112–20. http://dx.doi.org/10.59568/kjset-2024-3-1-11.
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Outdoor path loss propagation modeling is critical in the planning and design of the coverage area by the Global System for Mobile Communication (GSM). For the best prediction of GSM signal at any location within its coverage region, an accurate forecast based on critical characteristics and a mathematical model is necessary. Multiple studies on path loss propagation model prediction for GSM networks conducted at various semi-urban environments in Nigeria proclaimed that propagation path loss models may provide different results when utilized in environments other than those in which they were initially designed, that car drive-test methodology was used during the data collection, and that COST-231-Hata model provides closet prediction to the practical measure values. This paper created an appropriate path loss model based on the COST-23-Hata model and outdoor measurement at 1800 MHz frequency range for the semi-urban area of Kwara State, Nigeria. The created model was used and validated with the measured data and COST-231-Hata model at other different semi-urban environments in Nigeria. The results analysis shows that the created model performed satisfactorily given the closet path loss prediction to the practical measure path loss values at all the study locations. It also gives the lowest Square Root Means Error (SRME) and Standard Deviation (SD) in all the base stations that were tested in semi-urban environments. The newly created model would therefore be more appropriate for GSM 1800 network design and installation in semi-urban environments in Kwara State, Nigeria, as well as any other semi-urban locations in Nigeria.
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Castro, Guillermo, Rodolfo Feick, Mauricio Rodriguez, Reinaldo Valenzuela, and Dmitry Chizhik. "Outdoor-to-Indoor Empirical Path Loss Models: Analysis for Pico and Femto Cells in Street Canyons." IEEE Wireless Communications Letters 6, no. 4 (2017): 542–45. http://dx.doi.org/10.1109/lwc.2017.2715169.
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Cama-Pinto, Alejandro, Gabriel Piñeres-Espitia, José Caicedo-Ortiz, Elkin Ramírez-Cerpa, Leonardo Betancur-Agudelo, and Francisco Gómez-Mula. "Received strength signal intensity performance analysis in wireless sensor network using Arduino platform and XBee wireless modules." International Journal of Distributed Sensor Networks 13, no. 7 (2017): 155014771772269. http://dx.doi.org/10.1177/1550147717722691.
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Today, through the monitoring of agronomic variables, the wireless sensor networks are playing an increasingly important role in precision agriculture. Among the emerging technologies used to develop prototypes related to wireless sensor network, we find the Arduino platform and XBee radio modules from the DIGI Company. In this article, based on field tests, we conducted a comparative analysis of received strength signal intensity levels, calculation of path loss with “log-normal shadowing” and free-space path loss models. In addition, we measure packet loss for different transmission, distances and environments with respect to an “Arduino Mega” board, and radio modules XBee PRO S1 and XBee Pro S2. The tests for the packet loss and received strength signal intensity level show the best performance for the XBee Pro S2 in the indoor, outdoor, and rural scenarios.
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Tami, Diego, Cássio G. Rego, Dinael Guevara, et al. "Analysis of Heuristic Uniform Theory of Diffraction Coefficients for Electromagnetic Scattering Prediction." International Journal of Antennas and Propagation 2018 (2018): 1–11. http://dx.doi.org/10.1155/2018/3029152.
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We discuss three sets of heuristic coefficients used in uniform theory of diffraction (UTD) to characterize the electromagnetic scattering in realistic urban scenarios and canonical examples of diffraction by lossy conducting wedges using the three sets of heuristic coefficients and the Malyuzhinets solution as reference model. We compare not only the results of the canonical models but also their implementation in real outdoor scenarios. To predict the coverage of mobile networks, we used propagation models for outdoor environments by using a 3D ray-tracing model based on a brute-force algorithm for ray launching and a propagation model based on image theory. To evaluate each set of coefficients, we analyzed the mean and standard deviation of the absolute error between estimates and measured data in Ottawa, Canada; Valencia, Spain; and Cali, Colombia. Finally, we discuss the path loss prediction for each set of heuristic UTD coefficients in outdoor environment, as well as the comparison with the canonical results.
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Al-Saman, Ahmed, Michael Cheffena, Olakunle Elijah, Yousef A. Al-Gumaei, Sharul Kamal Abdul Rahim, and Tawfik Al-Hadhrami. "Survey of Millimeter-Wave Propagation Measurements and Models in Indoor Environments." Electronics 10, no. 14 (2021): 1653. http://dx.doi.org/10.3390/electronics10141653.
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The millimeter-wave (mmWave) is expected to deliver a huge bandwidth to address the future demands for higher data rate transmissions. However, one of the major challenges in the mmWave band is the increase in signal loss as the operating frequency increases. This has attracted several research interests both from academia and the industry for indoor and outdoor mmWave operations. This paper focuses on the works that have been carried out in the study of the mmWave channel measurement in indoor environments. A survey of the measurement techniques, prominent path loss models, analysis of path loss and delay spread for mmWave in different indoor environments is presented. This covers the mmWave frequencies from 28 GHz to 100 GHz that have been considered in the last two decades. In addition, the possible future trends for the mmWave indoor propagation studies and measurements have been discussed. These include the critical indoor environment, the roles of artificial intelligence, channel characterization for indoor devices, reconfigurable intelligent surfaces, and mmWave for 6G systems. This survey can help engineers and researchers to plan, design, and optimize reliable 5G wireless indoor networks. It will also motivate the researchers and engineering communities towards finding a better outcome in the future trends of the mmWave indoor wireless network for 6G systems and beyond.
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Muñoz, Juan, David Mancipe, Herman Fernández, Lorenzo Rubio, Vicent M. Rodrigo Peñarrocha, and Juan Reig. "Path Loss Characterization in an Outdoor Corridor Environment for IoT-5G in a Smart Campus University at 850 MHz and 3.5 GHz Frequency Bands." Sensors 23, no. 22 (2023): 9237. http://dx.doi.org/10.3390/s23229237.
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The usage scenarios defined in the ITU-M2150-1 recommendation for IMT-2020 systems, including enhanced Mobile Broadband (eMBB), Ultra-reliable Low-latency Communication (URLLC), and massive Machine Type Communication (mMTC), allow the possibility of accessing different services through the set of Radio Interface Technologies (RITs), Long-term Evolution (LTE), and New Radio (NR), which are components of RIT. The potential of the low and medium frequency bands allocated by the Federal Communications Commission (FCC) for the fifth generation of mobile communications (5G) is described. In addition, in the Internet of Things (IoT) applications that will be covered by the case of use of the mMTC are framed. In this sense, a propagation channel measurement campaign was carried out at 850 MHz and 5.9 GHz in a covered corridor environment, located in an open space within the facilities of the Pedagogical and Technological University of Colombia campus. The measurements were carried out in the time domain using a channel sounder based on a Universal Software Radio Peripheral (USRP) to obtain the received signal power levels over a range of separation distances between the transmitter and receiver from 2.00 m to 67.5 m. Then, a link budget was proposed to describe the path loss behavior as a function of these distances to obtain the parameters for the close-in free space reference distance (CI) and the floating intercept (FI) path loss prediction models. These parameters were estimated from the measurements made using the Minimum Mean Square Error (MMSE) approach. The estimated path loss exponent (PLE) values for both the CI and FI path loss models at 850 MHz and 3.5 GHz are in the range of 2.21 to 2.41, respectively. This shows that the multipath effect causes a lack of constructive interference to the received power signal for this type of outdoor corridor scenario. These results can be used in simulation tools to evaluate the path loss behavior and optimize the deployment of device and sensor network infrastructure to enable 5G-IoT connectivity in smart university campus scenarios.
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Diago-Mosquera, Melissa Eugenia, Alejandro Aragón-Zavala, and Mauricio Rodriguez. "Testing a 5G Communication System: Kriging-Aided O2I Path Loss Modeling Based on 3.5 GHz Measurement Analysis." Sensors 21, no. 20 (2021): 6716. http://dx.doi.org/10.3390/s21206716.
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Deep knowledge of how radio waves behave in a practical wireless channel is required for the effective planning and deployment of radio access networks in outdoor-to-indoor (O2I) environments. Using more than 400 non-line-of-sight (NLOS) radio measurements at 3.5 GHz, this study analyzes and validates a novel O2I measurement-based path loss prediction narrowband model that characterizes and estimates shadowing through Kriging techniques. The prediction results of the developed model are compared with those of the most traditional assumption of slow fading as a random variable: COST231, WINNER+, ITU-R, 3GPP urban microcell O2I models and field measured data. The results showed and guaranteed that the predicted path loss accuracy, expressed in terms of the mean error, standard deviation and root mean square error (RMSE) was significantly better with the proposed model; it considerably decreased the average error for both scenarios under evaluation.
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Talib, Mushtaq, Norazizah Binti Mohd Aripin, Noor Shamsiah Othman, and Adheed Hasan Sallomi. "Comprehensive Overview on Millimeter Wave Communications for 5G Networks Concentrating on Propagation Models for Different Urban Environments." Journal of Physics: Conference Series 2322, no. 1 (2022): 012095. http://dx.doi.org/10.1088/1742-6596/2322/1/012095.
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Abstract The global shortage of bandwidth prompted wireless carriers to move towards millimeter wave frequencies (mm-wave), a frequency spectrum that is underutilized by broadband communications networks. Despite the large number of studies and researches on the issue of millimeter wave propagation in outdoor and indoor environments, specifically environments with high population density, the issue of millimeter wave propagation in those environments remains somewhat ambiguous. For the exact purpose of the design and operation of the fifth-generation networks operating within the millimeter frequency spectrum, it has become necessary to obtain information about the wave propagation within those different environments. This paper presents a description of the wave propagation parameters and channel modeling prepared by several international groups, such as line and non-line of-sight (LOS & NLOS) probabilities and different propagation models to understand the mechanism of wave propagation within the millimeter range (0.5–70 GHz). This paper deals with simulating radio wave propagation in favour of different outdoor scenarios, calculating the path loss in several models and determining which models are most appropriate and best for certain environments.
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Anbazhagan, Rajesh, and Nakkeeran Rangaswamy. "Investigation on Mutual Contention Bandwidth Request Mechanisms in Two-Hop Relay Network with ITU-R Path Loss Models." ISRN Communications and Networking 2013 (May 29, 2013): 1–13. http://dx.doi.org/10.1155/2013/417132.
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The performance of two-hop contention based bandwidth request (BR) mechanism for WiMAX relay networks is investigated under ITU-R path loss models. In conventional WiMAX systems, the mobile stations (MS) update their contention window irrespective of their transmission failures. Those systems update their contention window on collision and due to channel error or unavailability of bandwidth. Further, these failure models have been suggested for single hop networks. The failure model in two-hop systems becomes complex since it may include additional failure events such as improper detection of codes and channel error due to varying path loss. Interestingly, these failure events (collision, channel error, unavailability of bandwidth, and improper detection of codes) do not occur evenly for both hops of a link. Hence, to set the contention window effectively, unique failure models are developed by considering the characteristics of BR mechanism and hop at which the BR is performed. In the proposed system, the two-hop BR is carried out with all combinations of message and code bandwidth request schemes. Among them, the message-code BR mechanism performs better under suburban fixed and outdoor to indoor or pedestrian environment, and code-code BR scheme performs better for vehicular environment.
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Al-Samman, Ahmed M., Tharek A. Rahman, Marwan H. Azmi, and M. N. Hindia. "Large-scale path loss models and time dispersion in an outdoor line-of-sight environment for 5G wireless communications." AEU - International Journal of Electronics and Communications 70, no. 11 (2016): 1515–21. http://dx.doi.org/10.1016/j.aeue.2016.09.009.
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Budalal, Asma Ali, and Md Rafiqul Islam. "Path loss models for outdoor environment—with a focus on rain attenuation impact on short-range millimeter-wave links." e-Prime - Advances in Electrical Engineering, Electronics and Energy 3 (March 2023): 100106. http://dx.doi.org/10.1016/j.prime.2023.100106.
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Fang, Zhou, Hengkai Zhao, Yichen Feng, et al. "Field Strength Prediction in High-Speed Train Carriages Using a Multi-Neural Network Ensemble Model with Optimized Output Weights." Applied Sciences 15, no. 5 (2025): 2709. https://doi.org/10.3390/app15052709.
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Accurate path loss prediction within train carriages is crucial for deploying base stations along high-speed railway lines. The field strength at receiving points inside carriages is influenced by outdoor signal transmission, penetration through window glass, and multiple reflections within the carriage, making it challenging for traditional models to predict the field strength distribution accurately. To address this issue, this paper proposes a machine learning-based path loss prediction method that incorporates ensemble techniques of multiple neural networks to enhance prediction stability and accuracy. The Whale Optimization Algorithm (WOA) is used to optimize the output weight configuration of each neural network in the ensemble model, thereby significantly improving the overall model performance. Specifically, on the test set, the WOA-optimized ensemble model reduces RMSE by 1.47 dB for CI, 0.47 dB for CNN, 0.93 dB for RNN, 1.38 dB for GNN, 0.1 dB for Transformer, 0.09 dB for AutoML, 0.33 dB for the GA-optimized ensemble model, and 0.18 dB for the PSO-optimized ensemble model.
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Qamar, Faizan, MHD Nour Hindia, Kaharudin Dimyati, et al. "Investigation of Future 5G-IoT Millimeter-Wave Network Performance at 38 GHz for Urban Microcell Outdoor Environment." Electronics 8, no. 5 (2019): 495. http://dx.doi.org/10.3390/electronics8050495.
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The advent of fifth-generation (5G) systems and their mechanics have introduced an unconventional frequency spectrum of high bandwidth with most falling under the millimeter wave (mmWave) spectrum. The benefit of adopting these bands of the frequency spectrum is two-fold. First, most of these bands appear to be unutilized and they are free, thus suggesting the absence of interference from other technologies. Second, the availability of a larger bandwidth offers higher data rates for all users, as there are higher numbers of users who are connected in a small geographical area, which is also stated as the Internet of Things (IoT). Nevertheless, high-frequency band poses several challenges in terms of coverage area limitations, signal attenuation, path and penetration losses, as well as scattering. Additionally, mmWave signal bands are susceptible to blockage from buildings and other structures, particularly in higher-density urban areas. Identifying the channel performance at a given frequency is indeed necessary to optimize communication efficiency between the transmitter and receiver. Therefore, this paper investigated the potential ability of mmWave path loss models, such as floating intercept (FI) and close-in (CI), based on real measurements gathered from urban microcell outdoor environments at 38 GHz conducted at the Universiti Teknologi Malaysia (UTM), Kuala Lumpur campus. The measurement data were obtained by using a narrow band mmWave channel sounder equipped with a steerable direction horn antenna. It investigated the potential of the network for outdoor scenarios of line-of-sight (LOS) and non-line-of-sight (NLOS) with both schemes of co- (vertical-vertical) and cross (vertical-horizontal) polarization. The parameters were selected to reflect the performance and the variances with other schemes, such as average users cell throughput, throughput of users that are at cell-edges, fairness index, and spectral efficiency. The outcomes were examined for various antenna configurations as well as at different channel bandwidths to prove the enhancement of overall network performance. This work showed that the CI path loss model predicted greater network performance for the LOS condition, and also estimated significant outcomes for the NLOS environment. The outputs proved that the FI path loss model, particularly for V-V antenna polarization, gave system simulation results that were unsuitable for the NLOS scenario.
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Askhedkar, Anjali R., Bharat S. Chaudhari, Maha Abdelhaq, Raed Alsaqour, Rashid Saeed, and Marco Zennaro. "LoRa Communication Using TVWS Frequencies: Range and Data Rate." Future Internet 15, no. 8 (2023): 270. http://dx.doi.org/10.3390/fi15080270.
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Low power wide area network (LPWAN) is a wireless communication technology that offers large coverage, low data rates, and low power consumption, making it a suitable choice for the growing Internet of Things and machine-to-machine communication applications. Long range (LoRa), an LPWAN technology, has recently been used in the industrial, scientific and medical (ISM) band for various low-power wireless applications. The coverage and data rate supported by these devices in the ISM band is well-studied in the literature. In this paper, we study the usage of TV white spaces (TVWS) for LoRa transmissions to address the growing spectrum demand. Additionally, the range and data rate of TVWS-based LoRa, for different transmission parameter values using different path-loss models and for various scenarios such as free space, outdoor and indoor are investigated. A path-loss model for TVWS-based LoRa is also proposed and explored, and the evaluations show that TVWS offers a longer range. This range and data rate study would be useful for efficient network planning and system design for TVWS-based LoRa LPWANs.
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Macedo, Alex, Thiago Costa, Edemir de Matos, et al. "Channel Analysis for 3.5 GHz Frequency in Airport." Journal of Communication and Information Systems 38, no. 1 (2023): 115–20. http://dx.doi.org/10.14209/jcis.2023.13.
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This letter presents an analysis of the radio propagation channel based on measurements at the 3.5 GHz frequency. The measurement campaigns were carried out inside the Valde-Cans airport using line-of-sight (LOS) transmissions. First, the channel small-scale dispersion parameters were extracted through channel probing and the results are similar to those obtained by ITU-R P.1238 for the bands below 15 GHz considering commercial indoor environments as well as for those using the 3.5 GHz band in outdoor environments utilizing WiMax OFDM-256 signals. Then, the floating-intercept (FI) and close-in (CI) models are applied and analyzed to evaluate the received signal behavior for co-polarized and cross polarized antennas. The results show that the CI path loss exponent values are close to the free space propagation loss model, while the FI model provides a lower root mean square error (RMSE) to the measured data. The results show that the FI and CI models are suitable for large-scale indoor propagation loss modeling for 5G networks with a frequency of 3.5 GHz.
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Bouzidi, Mohammed, Marshed Mohamed, Yaser Dalveren, Arild Moldsvor, Faouzi Alaya Cheikh, and Mohammad Derawi. "Propagation Measurements for IQRF Network in an Urban Environment." Sensors 22, no. 18 (2022): 7012. http://dx.doi.org/10.3390/s22187012.
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Recently, IQRF has emerged as a promising technology for the Internet of Things (IoT), owing to its ability to support short- and medium-range low-power communications. However, real world deployment of IQRF-based wireless sensor networks (WSNs) requires accurate path loss modelling to estimate network coverage and other performances. In the existing literature, extensive research on propagation modelling for IQRF network deployment in urban environments has not been provided yet. Therefore, this study proposes an empirical path loss model for the deployment of IQRF networks in a peer-to-peer configured system where the IQRF sensor nodes operate in the 868 MHz band. For this purpose, extensive measurement campaigns are conducted outdoor in an urban environment for Line-of-Sight (LoS) and Non-Line-of-Sight (NLoS) links. Furthermore, in order to evaluate the prediction accuracy of well-known empirical path loss models for urban environments, the measurements are compared with the predicted path loss values. The results show that the COST-231 Walfisch–Ikegami model has higher prediction accuracy and can be used for IQRF network planning in LoS links, while the COST-231 Hata model has better accuracy in NLoS links. On the other hand, the effects of antennas on the performance of IQRF transceivers (TRs) for LoS and NLoS links are also scrutinized. The use of IQRF TRs with a Straight-Line Dipole Antenna (SLDA) antenna is found to offer more stable results when compared to IQRF (TRs) with Meander Line Antenna (MLA) antenna. Therefore, it is believed that the findings presented in this article could offer useful insights for researchers interested in the development of IoT-based smart city applications.
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Azevedo, Joaquim Amândio, and Fábio Mendonça. "A Critical Review of the Propagation Models Employed in LoRa Systems." Sensors 24, no. 12 (2024): 3877. http://dx.doi.org/10.3390/s24123877.
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LoRa systems are emerging as a promising technology for wireless sensor networks due to their exceptional range and low power consumption. The successful deployment of LoRa networks relies on accurate propagation models to facilitate effective network planning. Therefore, this review explores the landscape of propagation models supporting LoRa networks. Specifically, we examine empirical propagation models commonly employed in communication systems, assessing their applicability across various environments such as outdoor, indoor, and within vegetation. Our investigation underscores the prevalence of logarithmic decay in most empirical models. In addition, we survey the relationship between model parameters and environmental factors, clearing their nuanced interplay. Analyzing published measurement results, we extract the log-distance model parameters to decipher environmental influences comprehensively. Drawing insights from published measurement results for LoRa, we compare them with the model’s outcomes, highlighting successes and limitations. We additionally explore the application of multi-slope models to LoRa measurements to evaluate its effectiveness in enhancing the accuracy of path loss prediction. Finally, we propose new lines for future research in propagation modelling to improve empirical models.
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Asma, Ali Budalal, Md Rafiqul Islam, Hadi Habaebi Mohamed, and Abd. Rahman Tharek. "The effects of rain fade on millimetre wave channel in tropical climate." Bulletin of Electrical Engineering and Informatics 8, no. 2 (2019): 653–64. https://doi.org/10.11591/eei.v8i2.1487.
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The main objective of this paper to determine multipath and time-varying channel behaviour of short-terrestrial millimetre-wave point-to-point radio links. In an attempt to invigorate the impact of rain attenuation on mm-wave channel parameters such as the RMS delay spread, path loss received power strength and Rician distribution with a K factor. A brief analysis of rain fading was presented based on the simultaneous measurement of one-minute rain rate and its effects on a short experimental link of 38 GHz. Rain fade average is observed as high as 16 dB for 300 m path at about 125 mm/hr rain intensity. The statistical spatial channel mode (SSCM) simulation software was utilized for an operating frequency of 38 GHz. To generate of power delay profile (PDP). For both omnidirectional and directional antenna. The RMS delay spread and path loss has been estimated using the environmental parameters of Kuala Lumpur city which illustrates the theoretical performances of 5G in Malaysia. It is observed that RMS delay spread, path loss received power strength and K factor effected dramatically by rain fade. (SSCM) simulation software has to be modified to consider rain fade dynamic characteristics to achieve ultra-reliability requirements of outdoor applications in the tropical regions. This study is important for understanding signal propagation phenomena in short distance and enabling the utilization of the millimetre wave band for an urban micro-cellular environment for 5G communication system.
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Neelakanta, Perambur, and Dolores De Groff. "Conceiving Inferential Prototypes of MIMO Channel Models via Buckingham’s Similitude Principle for 30+ GHz through THz Spectrum." Transactions on Networks and Communications 9, no. 3 (2021): 1–35. http://dx.doi.org/10.14738/tnc.93.10214.
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Facilitating newer bands of ‘unused’ segments (windows) of RF spectrum falling in the mm-wave range (above 30+ GHz) and seeking usable stretches across unallocated THz spectrum, could viably be considered for Multiple Input Multiple Output (MIMO) communications. This could accommodate the growing needs of multigigabit 3G/4G applications in outdoor-based backhauls in picocellular networks and in indoor-specific multimedia networking. However, in contrast with cellular and Wi-Fi, wireless systems supporting sub-mm wavelength transreceive communications in the outdoor electromagnetic (EM) ambient could face “drastically different propagation geometry”; also, in indoor contexts, envisaging pertinent spatial-multiplexing with directional, MIMO links could pose grossly diverse propagation geometry across a number of multipaths; as such, channel-models based on stochastic features of diverse MIMO-specific links in the desired test spectrum of mm-wave/THz band are sparsely known and almost non-existent. To alleviate this niche, a method is proposed here to infer sub-mm band MIMO channel-models (termed as “prototypes”) by judiciously sharing “similarity” of details available already pertinent to traditional “models” of lower-side EM spectrum, (namely, VLF through micro-/mm-wave). Relevant method proposed here relies on the “principle of similitude” due to Edgar Buckingham. Exemplar set of “model-to-(inferential)-prototype” transformations are derived and prescribed for an exhaustive set of fading channel models as well as, towards estimating path-loss of various channel statistics in the high-end test spectrum.
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Sulyman, Ahmed Iyanda, Hussein Seleem, Abdulmalik Alwarafy, Khaled M. Humadi, and Abdulhameed Alsanie. "Effects of Solar Radio Emissions on Outdoor Propagation Path Loss Models at 60 GHz Bands for Access/Backhaul Links and D2D Communications." IEEE Transactions on Antennas and Propagation 65, no. 12 (2017): 6624–35. http://dx.doi.org/10.1109/tap.2017.2759959.
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Al-Samman, Ahmed M., Marwan Hadri Azmi, Y. A. Al-Gumaei, et al. "Millimeter Wave Propagation Measurements and Characteristics for 5G System." Applied Sciences 10, no. 1 (2020): 335. http://dx.doi.org/10.3390/app10010335.
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In future 5G systems, the millimeter wave (mmWave) band will be used to support a large capacity for current mobile broadband. Therefore, the radio access technology (RAT) should be made available for 5G devices to help in distinct situations, for example device-to-device communications (D2D) and multi-hops. This paper presents ultra-wideband channel measurements for millimeter wave bands at 19, 28, and 38 GHz. We used an ultra-wideband channel sounder (1 GHz bandwidth) in an indoor to outdoor (I2O) environment for non-line-of-sight (NLOS) scenarios. In an NLOS environment, there is no direct path (line of sight), and all of the contributed paths are received from different physical objects by refection propagation phenomena. Hence, in this work, a directional horn antenna (high gain) was used at the transmitter, while an omnidirectional antenna was used at the receiver to collect the radio signals from all directions. The path loss and temporal dispersion were examined based on the acquired measurement data—the 5G propagation characteristics. Two different path loss models were used, namely close-in (CI) free space reference distance and alpha-beta-gamma (ABG) models. The time dispersion parameters were provided based on a mean excess delay, a root mean square (RMS) delay spread, and a maximum excess delay. The path loss exponent for this NLOS specific environment was found to be low for all of the proposed frequencies, and the RMS delay spread values were less than 30 ns for all of the measured frequencies, and the average RMS delay spread values were 19.2, 19.3, and 20.3 ns for 19, 28, and 38 GHz frequencies, respectively. Moreover, the mean excess delay values were found also at 26.1, 25.8, and 27.3 ns for 19, 28, and 38 GHz frequencies, respectively. The propagation signal through the NLOS channel at 19, 28, and 38 GHz was strong with a low delay; it is concluded that these bands are reliable for 5G systems in short-range applications.
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Akande, Olukunle Akinyinka, Onyebuchi Chikezie Nosiri, Agubor Cosmas Kemdirim, and Okpara Chinedu Reginald. "Implementation of Particle Swarm Optimization Technique for Enhanced Outdoor Network Coverage in Long Term Evolution Network in Port Harcourt, Nigeria." European Journal of Engineering Research and Science 2, no. 5 (2017): 36. http://dx.doi.org/10.24018/ejers.2017.2.5.346.
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This paper describes the development of optimized model for urban outdoor coverage in Long Term Evolution (LTE) network at 2300 MHz frequency band in Port Harcourt urban region, Nigeria. Signal attenuation and fluctuation remain amongst the major channel impairments for mobile radio communication systems. This arises as a result of model incompatibility with terrain and Line of Sight (LOS) obstruction of the channel signals. Some path loss models such as Okumura-Hata, COST 231, Ericsson 999, Egli and ECC-33 models were evaluated for suitability and compared with the modified model for the environments. The models were based on data collected from LTE base stations at three geographical locations in Port Harcourt namely- Rumuokoro, Eneka and Ikwerre roads respectively. The simulation was implemented using MATLAB R2014a software. The modified model was further optimized with some selected parameters such as Root Mean Square Error (RMSE) and Mean Absolute Error (MAE) using Particle Swarm Optimization (PSO) technique. The results obtained gave rise to 3.030dB for RMSE and 0.00162dB for MAE respectively. The results obtained from the PSO optimized model demonstrated a better performance which is suitable for cell coverage planning and smooth handoff processes.
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Akande, Olukunle Akinyinka, Onyebuchi Chikezie Nosiri, Agubor Cosmas Kemdirim, and Okpara Chinedu Reginald. "Implementation of Particle Swarm Optimization Technique for Enhanced Outdoor Network Coverage in Long Term Evolution Network in Port Harcourt, Nigeria." European Journal of Engineering and Technology Research 2, no. 5 (2017): 36–43. http://dx.doi.org/10.24018/ejeng.2017.2.5.346.
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This paper describes the development of optimized model for urban outdoor coverage in Long Term Evolution (LTE) network at 2300 MHz frequency band in Port Harcourt urban region, Nigeria. Signal attenuation and fluctuation remain amongst the major channel impairments for mobile radio communication systems. This arises as a result of model incompatibility with terrain and Line of Sight (LOS) obstruction of the channel signals. Some path loss models such as Okumura-Hata, COST 231, Ericsson 999, Egli and ECC-33 models were evaluated for suitability and compared with the modified model for the environments. The models were based on data collected from LTE base stations at three geographical locations in Port Harcourt namely- Rumuokoro, Eneka and Ikwerre roads respectively. The simulation was implemented using MATLAB R2014a software. The modified model was further optimized with some selected parameters such as Root Mean Square Error (RMSE) and Mean Absolute Error (MAE) using Particle Swarm Optimization (PSO) technique. The results obtained gave rise to 3.030dB for RMSE and 0.00162dB for MAE respectively. The results obtained from the PSO optimized model demonstrated a better performance which is suitable for cell coverage planning and smooth handoff processes.
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Hachemi, Mohammed Hicham, Sidi Mohammed Hadj Irid, Miloud Benchehima, and Mourad Hadjila. "Pedestrian mobility management for heterogeneous networks." Indonesian Journal of Electrical Engineering and Computer Science 28, no. 3 (2022): 1530–40. https://doi.org/10.11591/ijeecs.v28.i3.pp1530-1540.
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Pending the arrival of the next generation of 5G which is not yet deployed in some countries like Algeria, 4G LTE remains one of the main mobile networks to ensure adequate quality services. This paper presents a new approach called the epsilon Kalman filter with normalized least-mean-square (ϵKFNLMS) to ensure and improve the mobility management of pedestrian UEs in two-tier 4G LTE networks. ϵKFNLMS uses a two-step process: i) Tracking process, performed by Kalman filter, known for its very low estimation error. ii) Prediction process, performed by the variable step-size least mean squares (NLMS) algorithm (VSS-NLMS), known for its prediction of the future state at ”t+p”, where ”p” is the prediction footstep. Through different numerical simulations in several indoor/outdoor environments, the results show that the effectiveness of the proposed approach provides: a precise setting of the handover trigger, a lower mean square error (MSE), a faster convergence with a steady-state compared to the classical normalized LMS (NLMS) and Li-NLMS adaptive filters.
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K, Periyakaruppan, Manohari D, Kavitha M S, and Chellaprabha B. "OPTIMIZATION OF MANET WITH MIMO FOR FOREST APPLICATION USING ADVANCED ANTENNA MODELS." ICTACT Journal on Microelectronics 8, no. 1 (2022): 1318–22. http://dx.doi.org/10.21917/ijme.2022.0227.
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In this proposed work, the impulse response of the channel was measured to estimate the PL of an ad hoc network with more than one antenna in different environments, such as indoors, outdoors, in a forest, or in a combination of propagation environments. Some of these places are: Also, a brand-new way to find a PL path with the lowest cost is suggested and put into action. Assuming that all communication nodes are within the network''s transmission range, the suggested method can find the path in the network that loses the least amount of data. But this is seen as a problem, and it is planned that it will be fixed in our next project. So, based on the results, the proposed protocol is made and tested to make sure that communication goes through a secure route with the least amount of packet loss. Along with the transmission range limit, the power limit would also need to be worked on in the future because it is thought to be another important part of mobile ad hoc networks. Another important part of mobile ad hoc networks is how much energy they need. MANET runs on batteries, so energy, or power, is one of the most important parts of how it works.
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Janssen, Thomas, Noori BniLam, Michiel Aernouts, Rafael Berkvens, and Maarten Weyn. "LoRa 2.4 GHz Communication Link and Range." Sensors 20, no. 16 (2020): 4366. http://dx.doi.org/10.3390/s20164366.
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Recently, Semtech has released a Long Range (LoRa) chipset which operates at the globally available 2.4 GHz frequency band, on top of the existing sub-GHz, km-range offer, enabling hardware manufacturers to design region-independent chipsets. The SX1280 LoRa module promises an ultra-long communication range while withstanding heavy interference in this widely used band. In this paper, we first provide a mathematical description of the physical layer of LoRa in the 2.4 GHz band. Secondly, we investigate the maximum communication range of this technology in three different scenarios. Free space, indoor and urban path loss models are used to simulate the propagation of the 2.4 GHz LoRa modulated signal at different spreading factors and bandwidths. Additionally, we investigate the corresponding data rates. The results show a maximum range of 133 km in free space, 74 m in an indoor office-like environment and 443 m in an outdoor urban context. While a maximum data rate of 253.91 kbit/s can be achieved, the data rate at the longest possible range in every scenario equals 0.595 kbit/s. Due to the configurable bandwidth and lower data rates, LoRa outperforms other technologies in the 2.4 GHz band in terms of communication range. In addition, both communication and localization applications deployed in private LoRa networks can benefit from the increased bandwidth and localization accuracy of this system when compared to public sub-GHz networks.
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Liu, Weiquan, Cheng Wang, Xuesheng Bian, et al. "AE-GAN-Net: Learning Invariant Feature Descriptor to Match Ground Camera Images and a Large-Scale 3D Image-Based Point Cloud for Outdoor Augmented Reality." Remote Sensing 11, no. 19 (2019): 2243. http://dx.doi.org/10.3390/rs11192243.
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Establishing the spatial relationship between 2D images captured by real cameras and 3D models of the environment (2D and 3D space) is one way to achieve the virtual–real registration for Augmented Reality (AR) in outdoor environments. In this paper, we propose to match the 2D images captured by real cameras and the rendered images from the 3D image-based point cloud to indirectly establish the spatial relationship between 2D and 3D space. We call these two kinds of images as cross-domain images, because their imaging mechanisms and nature are quite different. However, unlike real camera images, the rendered images from the 3D image-based point cloud are inevitably contaminated with image distortion, blurred resolution, and obstructions, which makes image matching with the handcrafted descriptors or existing feature learning neural networks very challenging. Thus, we first propose a novel end-to-end network, AE-GAN-Net, consisting of two AutoEncoders (AEs) with Generative Adversarial Network (GAN) embedding, to learn invariant feature descriptors for cross-domain image matching. Second, a domain-consistent loss function, which balances image content and consistency of feature descriptors for cross-domain image pairs, is introduced to optimize AE-GAN-Net. AE-GAN-Net effectively captures domain-specific information, which is embedded into the learned feature descriptors, thus making the learned feature descriptors robust against image distortion, variations in viewpoints, spatial resolutions, rotation, and scaling. Experimental results show that AE-GAN-Net achieves state-of-the-art performance for image patch retrieval with the cross-domain image patch dataset, which is built from real camera images and the rendered images from 3D image-based point cloud. Finally, by evaluating virtual–real registration for AR on a campus by using the cross-domain image matching results, we demonstrate the feasibility of applying the proposed virtual–real registration to AR in outdoor environments.
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Prosvirov, Vladislav, Amjad Ali, Abdukodir Khakimov, and Yevgeni Koucheryavy. "Spatio-Temporal Coherence of mmWave/THz Channel Characteristics and Their Forecasting Using Video Frame Prediction Techniques." Mathematics 11, no. 17 (2023): 3634. http://dx.doi.org/10.3390/math11173634.
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Channel state information in millimeter wave (mmWave) and terahertz (THz) communications systems is vital for various tasks ranging from planning the optimal locations of BSs to efficient beam tracking mechanisms to handover design. Due to the use of large-scale phased antenna arrays and high sensitivity to environmental geometry and materials, precise propagation models for these bands are obtained via ray-tracing modeling. However, the propagation conditions in mmWave/THz systems may theoretically change at very small distances, that is, 1 mm–1 μm, which requires extreme computational effort for modeling. In this paper, we first will assess the effective correlation distances in mmWave/THz systems for different outdoor scenarios, user mobility patterns, and line-of-sight (LoS) and non-LoS (nLoS) conditions. As the metrics of interest, we utilize the angle of arrival/departure (AoA/AoD) and path loss of the first few strongest rays. Then, to reduce the computational efforts required for the ray-tracing procedure, we propose a methodology for the extrapolation and interpolation of these metrics based on the convolutional long short-term memory (ConvLSTM) model. The proposed methodology is based on a special representation of the channel state information in a form suitable for state-of-the-art video enhancement machine learning (ML) techniques, which allows for the use of their powerful prediction capabilities. To assess the prediction performance of the ConvLSTM model, we utilize precision and recall as the main metrics of interest. Our numerical results demonstrate that the channel state correlation in AoA/AoD parameters is preserved up until approximately 0.3–0.6 m, which is 300–600 times larger than the wavelength at 300 GHz. The use of a ConvLSTM model allows us to accurately predict AoA and AoD angles up to the 0.6 m distance with AoA being characterized by a higher mean squared error (MSE). Our results can be utilized to speed up ray-tracing simulations by selecting the grid step size, resulting in the desired trade-off between modeling accuracy and computational time. Additionally, it can also be utilized to improve beam tracking in mmWave/THz systems via a selection of the time step between beam realignment procedures.
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Bashar Fakhri, Ahmed, Sadik Kamel Gharghan, and Saleem Latteef Mohammed. "Path-loss modelling for WSN deployment in indoor and outdoor environments for medical applications." International Journal of Engineering & Technology 7, no. 3 (2018): 1666. http://dx.doi.org/10.14419/ijet.v7i3.15409.
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Wireless sensor networks (WSNs) and their applications have received significantly interested in the last few years. In WSN, knowing an accurate path-loss model as well as packet delivery should be taken into account for the successful distribution of several nodes in the net-work. This paper presents a path-loss modeling and performance evaluation of the ZigBee wireless standard. Received signal strength indi-cator (RSSI) measurements were achieved in outdoor and indoor environments to derive the path-loss based on Log-Normal Shadowing Model (LNSM). The path-loss parameters such as standard deviation and path loss exponents were estimated over point-to-point ZigBee WSN. In addition, the variances of received RSSI values and standard deviation for these values have been investigated. Furthermore, the data packets received is measured practically. Results revealed that the LNSM can be estimated to reflect the channel losses in both outdoor and indoor environments for medical application. The data delivery was achieved successfully of 100% in outdoor which better than indoor due to multipath propagation and shadowing. Moreover, the data packets delivery of the current work outperformed previous work.
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Yang, Zanru, Le Chung Tran, and Farzad Safaei. "Step Length Estimation Using the RSSI Method in Walking and Jogging Scenarios." Sensors 22, no. 4 (2022): 1640. http://dx.doi.org/10.3390/s22041640.
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In this paper, human step length was estimated based on wireless channel properties and the received signal strength indicator (RSSI) method. Path loss between two ankles of the person under test was converted from the RSSI, which was measured using our developed wearable transceivers with embedded micro-controllers in four scenarios, namely indoor walking, outdoor walking, indoor jogging, and outdoor jogging. For brevity, we call it on-ankle path loss. The histogram of the on-ankle path loss showed clearly that there were two humps, where the second hump was closely related to the maximum path loss, which, in turn, corresponded to the step length. This histogram can be well approximated by a two-term Gaussian fitting curve model. Based on the histogram of the experimental data and the two-term Gaussian fitting curve, we propose a novel filtering technique to filter out the path loss outliers, which helps set up the upper and lower thresholds of the path loss values used for the step length estimation. In particular, the upper threshold was found to be on the right side of the second Gaussian hump, and its value was a function of the mean value and the standard deviation of the second Gaussian hump. Meanwhile, the lower threshold lied on the left side of the second hump and was determined at the point where the survival rate of the measured data fell to 0.68, i.e., the cumulative distribution function (CDF) approached 0.32. The experimental data showed that the proposed filtering technique resulted in high accuracy in step length estimation with errors of only 10.15 mm for the indoor walking, 4.40 mm for the indoor jogging, 4.81 mm for the outdoor walking, and 10.84 mm for the outdoor jogging scenarios, respectively.
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Popoola, Segun I., Sanjay Misra, and Aderemi A. Atayero. "Outdoor Path Loss Predictions Based on Extreme Learning Machine." Wireless Personal Communications 99, no. 1 (2017): 441–60. http://dx.doi.org/10.1007/s11277-017-5119-x.
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Pandey, Suryashree, and Abhinandan Sarkar. "To Develop a Model for 4g LTE and Predictable 5G at 3500 Mhz that Would Predict the Path Loss for the Environment in Semi-Urban or Mixture of Urban and Rural Surroundings at Specific Geographical Locations." International Journal for Research in Applied Science and Engineering Technology 10, no. 5 (2022): 485–89. http://dx.doi.org/10.22214/ijraset.2022.42001.
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Abstract: In wireless communication, a planned network is given by the path loss model. Link budgeting, coverage prediction, and system performance optimization are indispensable in developing an accurate, simple, and general path loss model. To predict path loss in a particular environment each type of path loss propagation model is designed, it may be inaccurate in another different environment. In this paper, we are trying to predict a path loss model of Durgapur considering a particular place with a mixture of high-rise buildings, sub-urban, open, and foliage environments. For this proposal, the model area has been divided into twelve sectors taking 30° sectoring of radii 5 km and applying the path loss model for the calculation of path loss. Index Terms: Path loss, Predicted model, Outdoor propagation model consideration, Cell site selection, results, and discussions.
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Li, De-Wei, and Bryce Kendrick. "Functional and causal relationships between indoor and outdoor airborne fungi." Canadian Journal of Botany 74, no. 2 (1996): 194–209. http://dx.doi.org/10.1139/b96-024.
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From May to October, relationships of total numbers of airborne fungal propagules between indoor and outdoor sampling sites were very strong, particularly for Alternaria and Leptosphaeria, while that for unidentified ascospores was positive but to a lesser degree. Indoor and outdoor counts of Cladosporium, Epicoccum, Ganoderma, unidentified spores, hyphal fragments, and biodiversity (total number of fungal genera) were also significantly positively related. There appeared to be no functional relationship between Aspergillus/Penicillium conidia in indoor and outdoor air. From November to April, indoor and outdoor counts of Alternaria, Ganoderma, and hyphal fragments displayed negative relationships, but there was a positive correlation for Cladosporium, Epicoccum, Leptosphaeria, unidentified ascospores, total fungal spores, unidentified spores, and biodiversity. Once again, no functional relationship was detected between Aspergillus/Penicillium indoors and outdoors. The functional relationships of airborne fungi with indoor environmental factors are examined and discussed. A lack of causal relationships, as detected by path analysis, indicates that airborne spores of Alternaria, Leptosphaeria, unidentified ascospores, Coprinus, and Ganoderma came mainly from outdoor sources. All path models fitted this hypothesis well, except for Aspergillus/Penicillium. On the other hand, path analysis suggested that there were probably indoor sources of Cladosporium, Epicoccum, Aspergillus/Penicillium, unidentified basidiospores, and unidentified spores. Most of the models explained a large proportion of variance of indoor airborne fungi. Keywords: airborne fungal spores, redundancy analysis, path analysis.
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Zhong, Zhimeng, Jianyao Zhao, and Chao Li. "Outdoor-to-Indoor Channel Measurement and Coverage Analysis for 5G Typical Spectrums." International Journal of Antennas and Propagation 2019 (September 16, 2019): 1–10. http://dx.doi.org/10.1155/2019/3981678.
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The fifth-generation (5G) mobile communications system will adopt the millimeter wave (mmWave) band for outdoor-to-indoor (O2I) coverage to achieve ultrahigh data rate. However, it is a challenging task because of the large path loss and almost total blocking by building walls. In this work, we performed extensive measurements on the O2I propagation at 3.5, 4.9, and 28 GHz simultaneously by using a multiband channel sounder. We captured the path loss distribution and angular power arrival profiles. We also measured the penetration loss at 28 GHz through different kinds of glass windows. The widely adopted ordinary glass windows introduce the penetration loss of 3 to 12 dB that is acceptable and makes mmWave O2I coverage feasible. But the low-emissivity (low-E) windows that will be more popular in the future introduce 10 dB higher loss. The measurement results in this work can help analyse and anticipate the O2I coverage by mmWave, which is important for the design and deployment of the 5G network.
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Elechi, Promise, and Paul Osaretin Otasowie. "Comparison of Empirical Path Loss Propagation Models with Building Penetration Path Loss Model." International Journal on Communications Antenna and Propagation (IRECAP) 6, no. 2 (2016): 116. http://dx.doi.org/10.15866/irecap.v6i2.8013.
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FINDIK, CİHAN BARIŞ, and ÖZLEM ÖZGÜN. "RTPLTool: a software tool for path loss modeling in 5G outdoor systems." Turkish Journal of Electrical Engineering and Computer Sciences 30, no. 6 (2022): 2385–97. http://dx.doi.org/10.55730/1300-0632.3945.
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Gareh, Messaoud, Lotfi Djouane, Houcine Oudira, and Nazih Hamdiken. "Path Loss Models Optimization for Mobile Communication in Different Areas." Indonesian Journal of Electrical Engineering and Computer Science 3, no. 1 (2016): 126. http://dx.doi.org/10.11591/ijeecs.v3.i1.pp126-135.
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<p class="NormalItalique">In mobile radio systems, path loss models are necessary for proper planning, interference estimations, frequencies assignments and cell parameters which are basic for network planning process. Empirical models are the most adjustable models that can be suited to different types of environments. In this paper, data collected in Batna, Algeria is used to calculate the path loss for GSM (908-957 MHz). The measured path loss is compared with theoretical path loss estimated by the most widely empirical models «Cost123», «Hata», «SUI» and «Egli». The best model to estimate the measured path loss is optimized using genetic algorithm to predict path loss for suburban and rural area. The RMSE and the other test criteria between the actual and predicted data are calculated for various path loss models. It turned out that the adjusted COST 231 model outperforms the other studied models. The investigated results can help telecommunication engineers improve their planning and design of microcellular system.</p>
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Hu, L. Q., H. Yu, and Y. Chen. "Path loss models based on stochastic rays." IET Microwaves, Antennas & Propagation 1, no. 3 (2007): 602. http://dx.doi.org/10.1049/iet-map:20060346.
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Perez-Simbor, Sofia, Carlos Andreu, Concepcion Garcia-Pardo, Matteo Frasson, and Narcis Cardona. "UWB Path Loss Models for Ingestible Devices." IEEE Transactions on Antennas and Propagation 67, no. 8 (2019): 5025–34. http://dx.doi.org/10.1109/tap.2019.2891717.
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B. Majed, Mohammed, Tharek A. Rahman, and Omar Abdul Aziz. "Propagation Path Loss Modeling and Outdoor Coverage Measurements Review in Millimeter Wave Bands for 5G Cellular Communications." International Journal of Electrical and Computer Engineering (IJECE) 8, no. 4 (2018): 2254. http://dx.doi.org/10.11591/ijece.v8i4.pp2254-2260.
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The global bandwidth inadequacy facing wireless carriers has motivated the exploration of the underutilized millimeter wave (mm-wave) frequency spectrum for future broadband cellular communication networks, and mmWave band is one of the promising candidates due to wide spectrum. This paper presents propagation path loss and outdoor coverage and link budget measurements for frequencies above 6 GHz (mm-wave bands) using directional horn antennas at the transmitter and omnidirectional antennas at the receiver. This work presents measurements showing the propagation time delay spread and path loss as a function of separation distance for different frequencies and antenna pointing angles for many types of real-world environments. The data presented here show that at 28 GHz, 38 GHz and 60 GHz, unobstructed Line of Site (LOS) channels obey free space propagation path loss while non-LOS (NLOS) channels have large multipath delay spreads and can utilize many different pointing angles to provide propagation links. At 60 GHz, there is more path loss and smaller delay spreads. Power delay profiles PDPs were measured at every individual pointing angle for each TX and RX location, and integrating each of the PDPs to obtain received power as a function of pointing angle. The result shows that the mean RMS delay spread varies between 7.2 ns and 74.4 ns for 60 GHz and 28 GHz respectively in NLOS scenario.