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Use of GIS in Radio Frequency and Positioning ApplicationsJewell, Victoria Rose 12 September 2014 (has links)
GIS are geoprocessing programs that are commonly used to store and perform calculations on terrain data, maps, and other geospatial data. GIS offers the latest terrain and building data as well as tools to process this data. This thesis considers three applications of GIS data and software: a Large Scale Radio Frequency (RF) Model, a Medium Scale RF Model, and Indoor Positioning. The Large Scale RF Model estimates RF propagation using the latest terrain data supplied in GIS for frequencies ranging from 500 MHz to 5 GHz. The Medium Scale RF Model incorporates GIS building data to model WiFi systems at 2.4 GHz for a range of up to 300m. Both Models can be used by city planners and government offcials, who commonly use GIS for other geospatial and geostatistical information, to plan wireless broadband systems using GIS. An Indoor Positioning Experiment is also conducted to see if apriori knowledge of a building size, location, shape, and number of floors can aid in the RF geolocation of a target indoors. The experiment shows that correction of a target to within a building's boundaries reduces the location error of the target, and the vertical error is reduced by nearly half. / Master of Science
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ROCKET MOTOR PLUME EFFECTS ON TM SIGNALS - MODEL CORROBORATIONJohnston, Jerry W., LaPoint, Steve 10 1900 (has links)
International Telemetering Conference Proceedings / October 28-31, 1996 / Town and Country Hotel and Convention Center, San Diego, California / This paper presents the interim results of an effort to corroborate analytic model
predictions of the effects of rocket motor plume on telemetry signal RF propagation. When
space is available, telemetry receiving stations are purposely positioned to be outside the
region of a rocket motor's plume interaction with the RF path; therefore, little historical
data has been available to corroborate model predictions for specific rocket motor types
and altitudes. RF signal strength data was collected during the flight of HERA target
missile by White Sands Missile Range (WSMR) using a transportable telemetry receiving
site specifically positioned to be within the rocket plume region of influence at
intermediate altitudes. The collected data was analyzed and compared to an RF plume
attenuation model developed for pre-mission predictions. This work was directed by the
US Army Kwajalein Atoll (USAKA)/ Kwajalein Missile Range (KMR) Safety Division.
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Next-Generation Space Communications Technologies for Building Future Mars ConnectivityBonafini, Stefano 22 December 2022 (has links)
This decade will hopefully see the first human stepping on the Martian soil. Thus, supporting and enhancing the life quality of a future crew should be the driving theme for accomplishing manned missions on Mars. In this regard, an on-demand, ubiquitous, reliable, wideband, and low-latency connectivity seems of vital importance, both for in-situ and deep-space communications. Hence, this PhD dissertation aims to introduce innovation on this multi-faceted topic, to propose a new set of solutions which we refer to as Next Generation Communications on Mars (NGC-M). First, we discuss through extensive simulations the viability of an Extraterrestrial Long Term Evolution (E-LTE) porting, where a lander and a rover are re-allocated to compose a wireless local mobile network as the base station (BS) and user equipment (UE), respectively. Next, in order to model realistic Martian channels for further solid evaluations, we present a study on large and small-scale phenomena through a three-dimensional (3D) ray-tracing algorithm executed over 3D tile-based rendering of high-resolution Digital Elevation Model (DEM) of the ``Red Planet" surface. Then, we formulate a framework for the design of heterogeneous ground-to-space multi-layered (3D) networks implementing Cloud Radio Access Networks (C-RAN) for ``Towards 6G" Martian connectivity. The results will spread from simulations of the so-called splitting options, for the virtualization of baseband functionalities on non-dedicated hardware, to end-to-end (E2E) network emulations and on-hardware assessments. Finally, a decode-and-forward (DF) optical wireless multi-relay network (OWmRN), based on satellites orbiting the Lagrangian points (LPs), will be proposed for wideband exchanges of data between Mars and Earth. Data rate over time will be measured with respect to the selected shortest-path for relaying. The analysis of the various techniques, performed in a holistic and systemic view, focuses on viability and performance, taking into account trade-offs and constraints inherent to the unusual and challenging Martian application environment.
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An Antenna Specific Site Modeling Tool for Interactive Computation of Coverage Regions for Indoor Wireless CommunicationBhat, Nitin 08 April 1999 (has links)
A goal of indoor wireless communication is to strategically place RF base stations to obtain optimum signal coverage at the lowest cost and power. Traditionally, transceiver locations have been selected by human experts who rely on experience and heuristics to obtain a near-optimum placement. Current methods depend on involved on-site communication measurements and crude statistical modeling of the obtained data which is time consuming and prohibitive in cost. Given the inherent variability of the indoor environment, such a method often yields poor efficiency. As an example, it is possible that more power than required or extra number of transceivers were used. This thesis describes an interactive software system that can be used to aid transceiver placement. The tool is easy to use and is targeted at users who are not experts in wireless communication system design. Once the transceiver locations are selected by the user within a graphical floor plan, the system uses simple path-loss models to predict coverage regions for each transceiver. The coverage regions are highlighted to indicate expected coverage. Earlier work assumed isotropic transceivers and had limited directional transmitter support. This thesis describes how the tool has been enhanced to support a wide range of 3D antenna patterns as encountered in practical situations. The tool has also been expanded to accommodate more partition types and to report area of coverage. The resulting system is expected to be very useful in the practical deployment of indoor wireless systems. / Master of Science
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Evaluation of kriging interpolation methods as a tool for radio environment mapping / Willem Hendrik BoshoffBoshoff, Willem Hendrik January 2015 (has links)
In the journey toward optimal spectrum usage, techniques and concepts such as Cognitive
Radio and Dynamic Spectrum Access have enjoyed increasing attention in many
research projects. Dynamic Spectrum Access introduces the need for real-time RF spectrum
information in the form of Radio Environment Maps. This need motivates an investigation
into a hybrid approach of sample measurements and spatial interpolation
as opposed to using conventional propagation models.
Conventional propagation models, both path-general and path-specific, require information
of transmitters within the area of interest. Irregular Terrain Models such as the
Longley-Rice model, further require topographic information in order to consider the
effects of obstacles.
The proposed spatial interpolation technique, kriging, requires no information regarding
transmitters. Furthermore, Ordinary Kriging requires nothing other than measured
samples whereas other kriging variants such as Universal Kriging and Regression
Kriging can use additional information such as topographic data to aid in prediction
accuracy.
This dissertation investigates the performance of the three aforementioned kriging
variants in producing Radio Environment Maps of received power. For practical and
financial reasons, the received power measurement samples are generated using the
Longley-Rice Irregular Terrain Model and are, therefore, simulated measurements.
The experimental results indicate that kriging shows great promise as a tool to generate
Radio Environment Maps. It is found that Ordinary Kriging produces the most
accurate predictions of the three kriging methods and that prediction errors of less than
10 dB can be achieved even when using very low sampling densities. / MSc (Computer and Electronic Engineering), North-West University, Potchefstroom Campus, 2015
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Evaluation of kriging interpolation methods as a tool for radio environment mapping / Willem Hendrik BoshoffBoshoff, Willem Hendrik January 2015 (has links)
In the journey toward optimal spectrum usage, techniques and concepts such as Cognitive
Radio and Dynamic Spectrum Access have enjoyed increasing attention in many
research projects. Dynamic Spectrum Access introduces the need for real-time RF spectrum
information in the form of Radio Environment Maps. This need motivates an investigation
into a hybrid approach of sample measurements and spatial interpolation
as opposed to using conventional propagation models.
Conventional propagation models, both path-general and path-specific, require information
of transmitters within the area of interest. Irregular Terrain Models such as the
Longley-Rice model, further require topographic information in order to consider the
effects of obstacles.
The proposed spatial interpolation technique, kriging, requires no information regarding
transmitters. Furthermore, Ordinary Kriging requires nothing other than measured
samples whereas other kriging variants such as Universal Kriging and Regression
Kriging can use additional information such as topographic data to aid in prediction
accuracy.
This dissertation investigates the performance of the three aforementioned kriging
variants in producing Radio Environment Maps of received power. For practical and
financial reasons, the received power measurement samples are generated using the
Longley-Rice Irregular Terrain Model and are, therefore, simulated measurements.
The experimental results indicate that kriging shows great promise as a tool to generate
Radio Environment Maps. It is found that Ordinary Kriging produces the most
accurate predictions of the three kriging methods and that prediction errors of less than
10 dB can be achieved even when using very low sampling densities. / MSc (Computer and Electronic Engineering), North-West University, Potchefstroom Campus, 2015
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COAMPS modeled surface layer refractivity in the Roughness and Evaporation Duct experiment 2001 / Coupled Ocean Atmosphere Mesoscale Prediction System modeled surface layer refractivity in the Roughness and Evaporation Duct experiment 2001Newton, D. Adam 06 1900 (has links)
Approved for public release, distribution is unlimited / A study of the performance of the Coupled Ocean Atmosphere Mesoscale Prediction System (COAMPS) was performed based on collected METOC properties affecting radar propagation during the Roughness and Evaporation Duct (RED) experiment conducted off the windward coast of Oahu, HI. The measured refractivity influencing parameters (SST, air temperature, humidity, and wind speed) were compared to COAMPS predicted values. Using the NPS bulk evaporation duct model, profiles of the modified refractivity were computed from the buoy data and compared to profiles computed from the COAMPS data. The profiles were obtained concurrently with S-Band propagation measurements along a 26-km path. The radar propagation predictions created by APM from the modified refractivity profiles, derived from the measured METOC values and COAMPS modeled values, were compared to the in situ measured propagation losses. The mean RMS error of the prop loss predictions derived from the COAMPS forecasted METOC values was <4 dB compared to a mean RMS error of <3 dB from the in situ measurement derived prop loss predictions. Significantly larger errors occurred at the COAMPS analysis times. Overall, the results are very promising for this trade wind region, where the air is cooler than the relatively warm sea surface. / Lieutenant, United States Navy
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Calibração do modelo de propagação de dois raios com o modelo de Okumura-Hata. / Two ray propagation model calibration with Okumura-Hata model.Melo Rayo, Edna Margarita 27 October 2016 (has links)
Em telecomunicações é utilizada uma grande variedade de modelos de propagação para prever a intensidade do sinal de recepção num enlace de rádio. Os resultados dos modelos empíricos e dos modelos baseados em simplificações do problema eletromagnético apresentam, em geral, grande discrepância entre si, na análise do fenômeno de propagação. Por exemplo, o modelo de dois raios, que prevê atenuação de enlace com variação de 40 dB/década, na região de campo distante da antena de transmissão, quando colocada a uma certa altura da superfície de um solo condutor perfeito. Já o modelo empírico de Okumura-Hata exibe, para as mesmas condições geométricas, mas para solo de condutividade finita, uma variação da atenuação de enlace de 30 dB/década. Neste trabalho propõe-se uma calibração do modelo de dois raios para aumentar sua aderência aos resultados obtidos por Okumura-Hata num cenário real na faixa de frequências de 450MHz a 1900MHz para comprimentos de enlace entre 1 km e 20 km. Os resultados obtidos com o modelo proposto são comparados com os obtidos através de outros modelos apresentando boa aderência verificada através de uma comparação numérica particularmente com o modelo Okumura-Hata. / In telecommunications, there is a large variety of propagation models in order to predict the intensity of the receiving signal in a communication link. The empirical models and the models based on simplifications of the electromagnetic problem with theoretically obtained results show, in general, a significant disagreement, for the same propagation phenomenon. For example two-ray model predicts a path-loss of 40 dB/decade in the far-field region of a transmission antenna deployed at a certain height of the surface of a perfect conducting soil. On the other hand, the Okumura-Hata empirical model shows, for the same geometrical conditions, bur for a real soil, a path-loss of 30 dB/decade. This work proposes a calibration of the Two-Ray model for better adherence to the results obtained by Okumura-Hata in a real scenario for the frequency range 450MHz to 1900MHz and for a radio link length of 1 km to 20 km. The results obtained with the proposed model are compared with other model results showing good adherence through numeric comparison, in particular with the Okumura - Hata model.
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Calibração do modelo de propagação de dois raios com o modelo de Okumura-Hata. / Two ray propagation model calibration with Okumura-Hata model.Edna Margarita Melo Rayo 27 October 2016 (has links)
Em telecomunicações é utilizada uma grande variedade de modelos de propagação para prever a intensidade do sinal de recepção num enlace de rádio. Os resultados dos modelos empíricos e dos modelos baseados em simplificações do problema eletromagnético apresentam, em geral, grande discrepância entre si, na análise do fenômeno de propagação. Por exemplo, o modelo de dois raios, que prevê atenuação de enlace com variação de 40 dB/década, na região de campo distante da antena de transmissão, quando colocada a uma certa altura da superfície de um solo condutor perfeito. Já o modelo empírico de Okumura-Hata exibe, para as mesmas condições geométricas, mas para solo de condutividade finita, uma variação da atenuação de enlace de 30 dB/década. Neste trabalho propõe-se uma calibração do modelo de dois raios para aumentar sua aderência aos resultados obtidos por Okumura-Hata num cenário real na faixa de frequências de 450MHz a 1900MHz para comprimentos de enlace entre 1 km e 20 km. Os resultados obtidos com o modelo proposto são comparados com os obtidos através de outros modelos apresentando boa aderência verificada através de uma comparação numérica particularmente com o modelo Okumura-Hata. / In telecommunications, there is a large variety of propagation models in order to predict the intensity of the receiving signal in a communication link. The empirical models and the models based on simplifications of the electromagnetic problem with theoretically obtained results show, in general, a significant disagreement, for the same propagation phenomenon. For example two-ray model predicts a path-loss of 40 dB/decade in the far-field region of a transmission antenna deployed at a certain height of the surface of a perfect conducting soil. On the other hand, the Okumura-Hata empirical model shows, for the same geometrical conditions, bur for a real soil, a path-loss of 30 dB/decade. This work proposes a calibration of the Two-Ray model for better adherence to the results obtained by Okumura-Hata in a real scenario for the frequency range 450MHz to 1900MHz and for a radio link length of 1 km to 20 km. The results obtained with the proposed model are compared with other model results showing good adherence through numeric comparison, in particular with the Okumura - Hata model.
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Empirical RF Propagation Modeling of Human Body Motions for Activity ClassificationFu, Ruijun 19 December 2012 (has links)
"Many current and future medical devices are wearable, using the human body as a conduit for wireless communication, which implies that human body serves as a crucial part of the transmission medium in body area networks (BANs). Implantable medical devices such as Pacemaker and Cardiac Defibrillators are designed to provide patients with timely monitoring and treatment. Endoscopy capsules, pH Monitors and blood pressure sensors are used as clinical diagnostic tools to detect physiological abnormalities and replace traditional wired medical devices. Body-mounted sensors need to be investigated for use in providing a ubiquitous monitoring environment. In order to better design these medical devices, it is important to understand the propagation characteristics of channels for in-body and on- body wireless communication in BANs. The IEEE 802.15.6 Task Group 6 is officially working on the standardization of Body Area Network, including the channel modeling and communication protocol design. This thesis is focused on the propagation characteristics of human body movements. Specifically, standing, walking and jogging motions are measured, evaluated and analyzed using an empirical approach. Using a network analyzer, probabilistic models are derived for the communication links in the medical implant communication service band (MICS), the industrial scientific medical band (ISM) and the ultra- wideband (UWB) band. Statistical distributions of the received signal strength and second order statistics are presented to evaluate the link quality and outage performance for on-body to on- body communications at different antenna separations. The Normal distribution, Gamma distribution, Rayleigh distribution, Weibull distribution, Nakagami-m distribution, and Lognormal distribution are considered as potential models to describe the observed variation of received signal strength. Doppler spread in the frequency domain and coherence time in the time domain from temporal variations is analyzed to characterize the stability of the channels induced by human body movements. The shape of the Doppler spread spectrum is also investigated to describe the relationship of the power and frequency in the frequency domain. All these channel characteristics could be used in the design of communication protocols in BANs, as well as providing features to classify different human body activities. Realistic data extracted from built-in sensors in smart devices were used to assist in modeling and classification of human body movements along with the RF sensors. Variance, energy and frequency domain entropy of the data collected from accelerometer and orientation sensors are pre- processed as features to be used in machine learning algorithms. Activity classifiers with Backpropagation Network, Probabilistic Neural Network, k-Nearest Neighbor algorithm and Support Vector Machine are discussed and evaluated as means to discriminate human body motions. The detection accuracy can be improved with both RF and inertial sensors."
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