International Journal of Computer Applications, 2021
This paper systematically examines the response to QuasiMoment-Method (QMM) calibration, of the b... more This paper systematically examines the response to QuasiMoment-Method (QMM) calibration, of the basic COST231Walfisch-Ikegami, ITUR-Walfisch-Ikegami, and WalfischBertoni models. First, it is demonstrated that the component parameters of the models are suitable candidates for use as expansion/testing functions with QMM pathloss model calibration schemes; and thereafter, the basic models are subjected to calibration, using measurement data available in the open literature. Computational results reveal that the COST231-Walfisch-Ikegami and ITU-Walfisch-Ikegami models have virtually identical QMM-calibration root mean square error (RMSE) responses; and that the Walfisch-Bertoni model has better RMSE responses than both of them. A particular attribute revealed by the simulation results is that all QMM-calibrated ‘Walfisch-type’ basic models have excellent mean prediction error (MPE) metrics (in general, less than 0.001dB). In addition to pathloss prediction profiles, the paper also prese...
Progress In Electromagnetics Research Letters, 2011
Analytical investigations of the problem of dielectriccoated thin-wire antenna structures have in... more Analytical investigations of the problem of dielectriccoated thin-wire antenna structures have invariably focused on the physics of developing appropriate models for the dielectric insulation on the thin-wire conductors that serve as antenna for the structure. These include the frequency domain moment-method-based approaches in which the dielectric insulation is replaced by equivalent volume polarization currents; and the time-domain analysis based on the 'equivalent radius' concept. An earlier paper gave a physical interpretation to the frequency-domain solutions to suggest that the volume polarization currents derive from an equivalent static charge distribution, which excites an essentially radially-directed quasi-static field, confined to the region associated with the dielectric insulation. It is the main objective of this paper to investigate the veracity of the claims made in open literature as they concern the physics of the model for the dielectric insulation in terms of the electric field excited in the dielectric region. And to that end, simulation experiments were carried out, using a commercial Transmission Line Matrix (TLM) Method code, with which the characteristic features of the radial and axial components of the electric field within the dielectric region were investigated. The simulation results obtained from the experiments suggest that the field in question is not only of the quasi-static variety, but that it is also characterized by an axial component that meets the
International Journal of Computer Applications, 2020
This paper investigates the pathloss prediction characteristics of basic models, subjected to cal... more This paper investigates the pathloss prediction characteristics of basic models, subjected to calibration with the use of a novel technique, here referred to as the Quasi-MomentMethod, QMM. After a succinct description of the QMM calibration process, the paper presents computational results involving the calibration of three different basic models-the SUI, ECC33, and Ericsson models. The results reveal that the QMM typically reduces mean prediction (MP) and root mean square (RMS) errors by several tens of decibels. One other novelty introduced by the paper, is a comparison of contributions to total predicted pathloss, by components of the basic models, and their corresponding QMM-calibrated versions. General Terms Wireless Communications, Radiowave Propagation, Empirical Modeling
Prediction Characteristics of Quasi-Moment-Method Calibrated Pathloss Models, 2020
This paper investigates the pathloss prediction characteristics of basic models, subjected to cal... more This paper investigates the pathloss prediction characteristics of basic models, subjected to calibration with the use of a novel technique, here referred to as the Quasi-Moment-Method, QMM. After a succinct description of the QMM calibration process, the paper presents computational results involving the calibration of three different basic models-the SUI, ECC33, and Ericsson models. The results reveal that the QMM typically reduces mean prediction (MP) and root mean square (RMS) errors by several tens of decibels. One other novelty introduced by the paper, is a comparison of contributions to total predicted pathloss, by components of the basic models, and their corresponding QMM-calibrated versions.
On the Response of Basic Walfisch-Ikegami and Walfisch-Bertoni Models to QMM Calibration, 2021
This paper systematically examines the response to Quasi-Moment-Method (QMM) calibration, of the ... more This paper systematically examines the response to Quasi-Moment-Method (QMM) calibration, of the basic COST231-Walfisch-Ikegami, ITUR-Walfisch-Ikegami, and Walfisch-Bertoni models. First, it is demonstrated that the component parameters of the models are suitable candidates for use as expansion/testing functions with QMM pathloss model calibration schemes; and thereafter, the basic models are subjected to calibration, using measurement data available in the open literature. Computational results reveal that the COST231-Walfisch-Ikegami and ITU-Walfisch-Ikegami models have virtually identical QMM-calibration root mean square error (RMSE) responses; and that the Walfisch-Bertoni model has better RMSE responses than both of them. A particular attribute revealed by the simulation results is that all QMM-calibrated 'Walfisch-type' basic models have excellent mean prediction error (MPE) metrics (in general, less than 0.001dB). In addition to pathloss prediction profiles, the paper also presents profiles of disaggregated net pathloss, in terms of contributions by component parameters, including 'rooftop-to-street' diffraction and scatter loss and multiscreen diffraction loss.
Progress In Electromagnetics Research Letters, 2011
Analytical investigations of the problem of dielectriccoated thin-wire antenna structures have in... more Analytical investigations of the problem of dielectriccoated thin-wire antenna structures have invariably focused on the physics of developing appropriate models for the dielectric insulation on the thin-wire conductors that serve as antenna for the structure. These include the frequency domain moment-method-based approaches in which the dielectric insulation is replaced by equivalent volume polarization currents; and the time-domain analysis based on the 'equivalent radius' concept.
Analytical investigations of the problem of dielectric- coated thin-wire antenna structures have ... more Analytical investigations of the problem of dielectric- coated thin-wire antenna structures have invariably focused on the physics of developing appropriate models for the dielectric insulation on the thin-wire conductors that serve as antenna for the structure. These include the frequency domain moment-method-based approaches in which the dielectric insulation is replaced by equivalent volume polarization currents; and the time-domain analysis based
International Journal of Computer Applications, 2021
This paper systematically examines the response to QuasiMoment-Method (QMM) calibration, of the b... more This paper systematically examines the response to QuasiMoment-Method (QMM) calibration, of the basic COST231Walfisch-Ikegami, ITUR-Walfisch-Ikegami, and WalfischBertoni models. First, it is demonstrated that the component parameters of the models are suitable candidates for use as expansion/testing functions with QMM pathloss model calibration schemes; and thereafter, the basic models are subjected to calibration, using measurement data available in the open literature. Computational results reveal that the COST231-Walfisch-Ikegami and ITU-Walfisch-Ikegami models have virtually identical QMM-calibration root mean square error (RMSE) responses; and that the Walfisch-Bertoni model has better RMSE responses than both of them. A particular attribute revealed by the simulation results is that all QMM-calibrated ‘Walfisch-type’ basic models have excellent mean prediction error (MPE) metrics (in general, less than 0.001dB). In addition to pathloss prediction profiles, the paper also prese...
Progress In Electromagnetics Research Letters, 2011
Analytical investigations of the problem of dielectriccoated thin-wire antenna structures have in... more Analytical investigations of the problem of dielectriccoated thin-wire antenna structures have invariably focused on the physics of developing appropriate models for the dielectric insulation on the thin-wire conductors that serve as antenna for the structure. These include the frequency domain moment-method-based approaches in which the dielectric insulation is replaced by equivalent volume polarization currents; and the time-domain analysis based on the 'equivalent radius' concept. An earlier paper gave a physical interpretation to the frequency-domain solutions to suggest that the volume polarization currents derive from an equivalent static charge distribution, which excites an essentially radially-directed quasi-static field, confined to the region associated with the dielectric insulation. It is the main objective of this paper to investigate the veracity of the claims made in open literature as they concern the physics of the model for the dielectric insulation in terms of the electric field excited in the dielectric region. And to that end, simulation experiments were carried out, using a commercial Transmission Line Matrix (TLM) Method code, with which the characteristic features of the radial and axial components of the electric field within the dielectric region were investigated. The simulation results obtained from the experiments suggest that the field in question is not only of the quasi-static variety, but that it is also characterized by an axial component that meets the
International Journal of Computer Applications, 2020
This paper investigates the pathloss prediction characteristics of basic models, subjected to cal... more This paper investigates the pathloss prediction characteristics of basic models, subjected to calibration with the use of a novel technique, here referred to as the Quasi-MomentMethod, QMM. After a succinct description of the QMM calibration process, the paper presents computational results involving the calibration of three different basic models-the SUI, ECC33, and Ericsson models. The results reveal that the QMM typically reduces mean prediction (MP) and root mean square (RMS) errors by several tens of decibels. One other novelty introduced by the paper, is a comparison of contributions to total predicted pathloss, by components of the basic models, and their corresponding QMM-calibrated versions. General Terms Wireless Communications, Radiowave Propagation, Empirical Modeling
Prediction Characteristics of Quasi-Moment-Method Calibrated Pathloss Models, 2020
This paper investigates the pathloss prediction characteristics of basic models, subjected to cal... more This paper investigates the pathloss prediction characteristics of basic models, subjected to calibration with the use of a novel technique, here referred to as the Quasi-Moment-Method, QMM. After a succinct description of the QMM calibration process, the paper presents computational results involving the calibration of three different basic models-the SUI, ECC33, and Ericsson models. The results reveal that the QMM typically reduces mean prediction (MP) and root mean square (RMS) errors by several tens of decibels. One other novelty introduced by the paper, is a comparison of contributions to total predicted pathloss, by components of the basic models, and their corresponding QMM-calibrated versions.
On the Response of Basic Walfisch-Ikegami and Walfisch-Bertoni Models to QMM Calibration, 2021
This paper systematically examines the response to Quasi-Moment-Method (QMM) calibration, of the ... more This paper systematically examines the response to Quasi-Moment-Method (QMM) calibration, of the basic COST231-Walfisch-Ikegami, ITUR-Walfisch-Ikegami, and Walfisch-Bertoni models. First, it is demonstrated that the component parameters of the models are suitable candidates for use as expansion/testing functions with QMM pathloss model calibration schemes; and thereafter, the basic models are subjected to calibration, using measurement data available in the open literature. Computational results reveal that the COST231-Walfisch-Ikegami and ITU-Walfisch-Ikegami models have virtually identical QMM-calibration root mean square error (RMSE) responses; and that the Walfisch-Bertoni model has better RMSE responses than both of them. A particular attribute revealed by the simulation results is that all QMM-calibrated 'Walfisch-type' basic models have excellent mean prediction error (MPE) metrics (in general, less than 0.001dB). In addition to pathloss prediction profiles, the paper also presents profiles of disaggregated net pathloss, in terms of contributions by component parameters, including 'rooftop-to-street' diffraction and scatter loss and multiscreen diffraction loss.
Progress In Electromagnetics Research Letters, 2011
Analytical investigations of the problem of dielectriccoated thin-wire antenna structures have in... more Analytical investigations of the problem of dielectriccoated thin-wire antenna structures have invariably focused on the physics of developing appropriate models for the dielectric insulation on the thin-wire conductors that serve as antenna for the structure. These include the frequency domain moment-method-based approaches in which the dielectric insulation is replaced by equivalent volume polarization currents; and the time-domain analysis based on the 'equivalent radius' concept.
Analytical investigations of the problem of dielectric- coated thin-wire antenna structures have ... more Analytical investigations of the problem of dielectric- coated thin-wire antenna structures have invariably focused on the physics of developing appropriate models for the dielectric insulation on the thin-wire conductors that serve as antenna for the structure. These include the frequency domain moment-method-based approaches in which the dielectric insulation is replaced by equivalent volume polarization currents; and the time-domain analysis based
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