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Research on TD-LTE wireless communication network propagation model optimization based on visual simulation and GIS

EURASIP JOURNAL ON WIRELESS COMMUNICATIONS AND NETWORKING 2021年第1期2021卷 1-14页

作者： Li, Tongyan Hua, Shuchun Kang, Le Chang, Sheng-Hung Nanjing Polytech Inst Sch Econ & Management Nanjing Peoples R China Jinling Inst Technol Business Sch Nanjing Peoples R China Hubei Univ Econ Sch Business Adm Wuhan Peoples R China

With the support of GIS spatial analysis technology, based on an in-depth study of the wireless propagation environment of a city, combined with the analysis of project requirements, it proposes to use the SPM model to correct the propagation model parameters, using SPM. The wireless propagation model, and research and analysis of the SPM wireless propagation model correction algorithm, further corrected the parameters of a city's SPM wireless propagation model. On this basis, the propagation loss of several classic propagation models in different environments is compared, and the SPM propagation model suitable for the signal frequency band and propagation environment of this study is selected. The correction of the SPM propagation model is based on the designed correction principle and correction process, that is, the weighted least square method is used to fit and analyze the measured level data to obtain an SPM prediction improvement model with local characteristics, and according to the designed verification link. Evaluation of the correction results shows that the accuracy requirements are met. Based on the corrected SPM prediction model, link loss calculations were performed on the 13 test base stations studied in the experiment, and the effective coverage radius of each base station community was obtained. In combination with GIS technology, model parameters and workers of each base station participated in the electronic map loading of the area Go to the network planning software to get the wireless signal coverage prediction map of each base station. Finally, according to the technical requirements of the TD-LTE system network planning and network optimization engineering, the objectiveness and rationality of the site selection and number of base stations in the area were verified, and specific problems regarding poor coverage and overlapping coverage in the area were proposed.

关键词： TD-LTE Propagation model Path loss coverage prediction Network optimization spalling

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Optimization of Multi-Frequency Network With DVB-T2 Services for Regions With Complex Geographies: A Case Study of Nepal

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IEEE TRANSACTIONS ON BROADCASTING 2021年第1期67卷 299-312页

作者： Nepal, Subodh Thang, Duong Quang Higashino, Takeshi Okada, Minoru Nara Inst Sci & Technol Grad Sch Sci & Technol Nara 6300192 Japan

Planning for Multi-Frequency Network (MFN) with Digital Video Broadcasting-Second Generation Terrestrial (DVB-T2) services is particularly useful during the transition from analog to digital broadcasting. For efficient management of service area as well as resource allocation, it is necessary to administer the use of network parameters, e.g., transmit power, frequency channels, and antenna parameters. This article, therefore, proposes a coverage maximization scheme for the MFN with the DVB-T2 system by using the Genetic Algorithm. In order to effectively perform the optimization over regions with diverse geographical structures, a propagation prediction method considering the complex orography together with Digital Elevation Model is used to predict signal strength at each receiving location. Based on the received signal strength and standard Quality of Service criteria, the overall radio coverage of the network is maximized using the optimum values of transmit power levels, frequency channels, and antenna parameters. Although our analysis and simulations are based on the MFN network in Nepal, the methodology presented in this work can be applied in any region with some alterations in geographical and meteorological parameters.

关键词： Optimization Radio transmitters Receivers Digital video broadcasting Predictive models Planning Transmitting antennas Co-channel interference coverage optimization coverage prediction DVB-T2 network parameter optimization spectrum usage

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Predicting prime path coverage using regression analysis at method level

Predicting prime path coverage using regression analysis at ...

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作者： Silva, Keslley Lima da

Test coverage criteria help the tester in analyzing the quality of the test suite, especially in an evolving system where it can be used to guide the prioritization of regression tests and the testing effort of new code. However, coverage analysis of more powerful cri teria such as path coverage is still challenging due to the lack of supporting tools. As a consequence, the tester evaluates a test suite quality employing more basic coverage criteria (e.g., node coverage and edge coverage), which are the ones that are supported by tools. In this work, we evaluate the opportunity of using machine learning algorithms to estimate the prime-path coverage of a test suite at the method level. We followed the Knowledge Discovery in Database process and a dataset built from 9 real-world projects to devise three regression models for prime-path prediction. We compare four different machine learning algorithms and conduct a fine-grained feature analysis to investigate the factors that most impact the prediction accuracy. Our experimental results show that a suitable predictive model uses as input data only five source code metrics and one basic test coverage metric. Our evaluation shows that the best model achieves an MAE of 0.016 (1,6%) on the cross-validation (internal validation) and an MAE of 0.06 (6%) on the ex ternal validation. Finally, we observed that good prediction models can be generated from common code metrics although the use of a simple test metric such as branch coverage can improve even more the prediction performance of the model. ...

关键词： Algoritmos coverage prediction Aprendizagem : Maquina Code coverage Teste : Software Regression analysis Dissertação

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Predicting Prime Path coverage Using Regression Analysis 20

Predicting Prime Path Coverage Using Regression Analysis

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34th Brazilian Symposium on Software Engineering (SBES)

作者： Silva, Keslley Cota, Erika Univ Fed Rio Grande do Sul PPGC Inst Informat Porto Alegre RS Brazil

ISBN: (纸本)9781450387538

Test coverage criteria help the tester to analyze the quality of the test suite, especially in an evolving system where it can be used to guide the prioritization of regression tests as well as the testing effort of new code. However, coverage analysis of more powerful criteria such as path coverage is still a challenging task due to the lack of supporting tools. In this paper, we evaluate the opportunity of using machine learning algorithms to estimate the prime-path coverage of a test suite at method level. We use a knowledge discovery in database framework and a dataset built from real-world projects to devise a regression model for prime-path prediction. Experimental results demonstrate that a suitable predictive model can be defined with RMSE 0.118 on cross-validation and an average error rate of 26% in a cross-project scenario. We also show how the tester can use the proposed strategy in a practical cross-project scenario.

关键词： Software testing coverage prediction Code coverage Regression analysis

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Effects of Diffraction and Ground Reflection on Ray-Tracing-Based coverage predictions in Urban Microcellular Environments

Effects of Diffraction and Ground Reflection on Ray-Tracing-...

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Cross Strait Quad-Regional Radio Science and Wireless Technology Conference (CSQRWC)

作者： Liu, Z-Y Zhang, T-L Guo, L-X Li, J. Xidian Univ Sch Phys & Optoelect Engn Xian Shaanxi Peoples R China

ISBN: (纸本)9781538664230

Two-and-one-half dimensional ray tracing models, in combination with the uniform theory of diffraction and geometrical optics, are widely employed for propagation prediction in urban microcellular environments because of their high efficiency and reliable prediction accuracy. In this study, an improved ray tracing algorithm based on the "orientation face set" concept and on the improved 2D polar sweep algorithm is used. The aim of this paper is mainly to analyze the effects of different propagation mechanisms on ray-tracing-based coverage predictions in urban microcellular environments. In addition, the effects associated with the coverage prediction are visually represented.

关键词： coverage prediction diffraction reflection ray tracing urban microcellular environment

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A Fast Ray-tracing Algorithm for Rugged Terrain

A Fast Ray-tracing Algorithm for Rugged Terrain

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Cross Strait Quad-Regional Radio Science and Wireless Technology Conference (CSQRWC)

作者： Hu, Shuo Guo, Li-Xin Liu, Zhong-Yu Xidian Univ Sch Phys & Optoelect Engn Xian Peoples R China

ISBN: (纸本)9781728113722

In order to analyze coverage prediction of irregular terrain using ray tracing model, some form of accelerating must be performed to improve computational efficiency. A new image source tree structure is proposed to improving the efficiency of coverage prediction. This paper describes an accelerating algorithm that has proven effective in working with large terrain data files which extracted from SRTM Digital Elevation Model (DEM) database. On the basis of triangular subdivision of DEM data, a lot of coverage predictions are illustrated to analyze the field distribution and channel characteristic using ray-tracing method.

关键词： ray-tracing image tree wave propagation irregular terrain triangular subdivision coverage prediction

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TV White Space and LTE Network Optimization Toward Energy Efficiency in Suburban and Rural Scenarios

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IEEE TRANSACTIONS ON BROADCASTING 2018年第1期64卷 164-171页

作者： Martinez Alonso, Rodney Plets, David Deruyck, Margot Martens, Luc Guillen Nieto, Glauco Joseph, Wout LACETEL Havana 19200 Cuba Univ Ghent INTEC B-9052 Ghent Belgium

The radio spectrum is a limited resource. Demand for wireless communication services is increasing exponentially, stressing the availability of radio spectrum to accommodate new services. TV white space (TVWS) technologies allow a dynamic usage of the spectrum. These technologies provide wireless connectivity, in the channels of the very high frequency and ultra high frequency television broadcasting bands. In this paper, we investigate and compare the coverage range, network capacity, and network energy efficiency for TVWS technologies and LTE. We consider Ghent, Belgium, and Boyeros, Havana, Cuba, to evaluate a realistic outdoor suburban and rural area, respectively. The comparison shows that TVWS networks have an energy efficiency 9-12 times higher than LTE networks.

关键词： Wireless networks network planning coverage prediction TVWS energy efficiency

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Optimal null steering method in uniformly excited equally spaced linear arrays by optimising two edge elements

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ELECTRONICS LETTERS 2017年第13期53卷 835-836页

作者： Mohammed, J. R. Ninevah Univ Coll Elect Engn Mosul 41001 Iraq

The implementation of the feeding network in the arrays that composed of a large number of elements and using non- uniform excitations is a real challenging issue. The complexity of the feeding network can be greatly simplified by using uniformly excited arrays. However, such arrays suffer from sidelobe limitation. An optimised approach for sector sidelobe nulling in the equally spaced linear array pattern with uniform excitations except for two edge elements is presented. The genetic algorithm and particle swarm optimisation are independently used to find the optimal values of the amplitude and phase excitations for those edge elements.

关键词： digital television particle swarm optimisation grey systems UHF radio propagation improved ITU-R model digital terrestrial television propagation path loss prediction coverage prediction DTT system planning DTT system dimensioning process Recommendation ITU-R P 1812-4 propagation path loss prediction accuracy improvement outdoor environments Caracas city bioinspired technique particle swarm optimisation PSO received signal level measurements fixed reception conditions RMS error grey relation grade mean absolute percentage error

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A Novel Inversion Method for Outdoor coverage prediction in Wireless Cellular Network

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IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY 2010年第1期59卷 36-47页

作者： Wang, Yuhao Si, Yang Leung, Henry Nanchang Univ Sch Informat Engn Mobile Lab Nanchang 330031 Peoples R China Qinghai Univ Dept Hydroelect Engn Xining 810016 Peoples R China Univ Calgary Dept Elect & Comp Engn Calgary AB T2N 1N4 Canada

A novel coverage-prediction method for outdoor radio propagation based on the inversion theory is proposed here. coverage prediction in a wireless cellular network is treated as an inverse problem instead of using high-precision geometric modeling. More precisely, the problem is solved by an inversion of the measured data under some a priori constraints, and the complicated propagation-prediction problem is reduced to solving a system of large-scale ill-condition equations. The effectiveness of the proposed method is demonstrated by using experiments under various radio environments in Guangdong, China. The prediction results are approximately consistent with independent checking samples, and the proposed strategy is compared with other existing approaches.

关键词： coverage prediction inversion method measurement radio propagation

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Joint Ray Launching Method for Indoor to Outdoor Propagation prediction Based on Ray Aggregation 9

Joint Ray Launching Method for Indoor to Outdoor Propagation...

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9th European Conference on Antennas and Propagation EuCAP

作者： Xia, Bing Lai, Zhihua Zhang, Jie Univ Sheffield Commun Grp Mappin St Sheffield S1 3JD S Yorkshire England Ranplan Wireless Network Design Ltd Innovat Ctr Sheffield S1 4DP S Yorkshire England

ISBN: (纸本)9788890701856

A joint indoor to outdoor ray launching algorithm is proposed in this paper. Different resolutions are considered for indoor and outdoor simulations. Instead of using conventional sampling technique to extract rays from a finer resolution, a novel method, named Ray Aggregation, is applied to minimise the loss of accuracy while benefiting from the computational cost of a coarse resolution. Furthermore, this model will be demonstrated with two simulations based on the general 2.4 GHz 802.11n wireless local area network. Finally, the corresponding measurements will be presented to verify the accuracy of the proposed model.

关键词： propagation indoor to outdoor coverage prediction

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