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global-positioning-system
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An Efficient GPS-based System for Reliable Infraction Detection in Highways
, M.Sc. Thesis Sharif University of Technology ; Manzuri, Mohammad Taghi (Supervisor)
Abstract
In this research we explain a new method for detection of infraction behavior of drivers in highways. There are different approaches to find and register such abnormal and illegal behaviors, such as a camera-based monitoring system and Radar-based infraction detectors. But none of them can recognize and register the weave through traffic or spiral motions of vehicles, because the radar-based systems do not have adequate latitudinal–resolution while their longitudinal-accuracy is moderate. Moreover, the locations of radars are fixed and, the drivers adapt the velocity of their vehicles based on the position of the known radars. Consequently, these systems are inherently not suitable for our...
Satellite Constellation and Satellite System Design Applied to IRAN Local positioning System
, M.Sc. Thesis Sharif University of Technology ; Fathi, Mohsen (Supervisor)
Abstract
In this writing, Satellite Constellation and Satellite System Design, with a focus on satellite design, for local positioning in Iran, have been considered, in line with the subject of the thesis. The design process have been conducted consistent with the system literature and all the system elements for a satellite Constellation, have been presented as much as possible. In some cases, application of experimental equations in space handbooks do not have significant statistical credit and this fact has been mentioned in those handbooks. For each mission, it is necessary to provide special methods and corresponding requirements. At the end of the satellite design it is found that the design...
Attitude Determination Using GPS Carrier Phase and Doppler Measurements
, M.Sc. Thesis Sharif University of Technology ; Ghanbarpour Asl, Habib (Supervisor)
Abstract
By using of raw measurements of GPS receivers including carrier phase and Doppler frequency we can estimate attitude parameters of a platform on which the receivers are installed in a proper orientation. In this research attitude parameters are estimated based on quaternions. To this end a discrete Kalman filter was designed to predict the attitude parameters by using of carrier phase double difference measurements and then update the predicted parameters by using of Doppler frequency double difference measurements. Doppler frequency measurements were used to estimate the quaternion rates which are used in update step of Kalman filter algorithm. A robust algorithm for carrier phase ambiguity...
Development of Cascade Fuzzy Filters in Integrated INS-DVL-GPS Navigation
, M.Sc. Thesis Sharif University of Technology ; Salarieh, Hassan (Supervisor)
Abstract
Navigation is the science of determining the velocity and attitude of a moving object in every given moment. There have been many methods for navigation. Nowadays with the advancement of technology, advanced navigation systems have been developed. Although each of these navigation systems have their pros and cons, in order to improve the overall performance of the system and to solve their problems, these systems are integrated.The goal of this project is to present an integrated cascade method to decrease error and also decrease dependence on GPS. In this project, INS, DVL & GPS are integrated with the cascade method.To achieve this, INS-GPS and INS-DVL integration are first performed. The...
Multi-GNSS constellation fusion based on statistical features of positioning error
, Article 26th Iranian Conference on Electrical Engineering, ICEE 2018, 8 May 2018 through 10 May 2018 ; 2018 , Pages 725-730 ; 9781538649169 (ISBN) ; Behnia, F ; Marvasti, F ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2018
Abstract
With the advent of new positioning services, one can reach more satellites these days to find his position. Using a combination of satellites which belong to different constellations needs some considerations like addressing biases between their time references. Each constellation has progressed to the point that they have enough satellites to provide accurate position separately. According to this fact, we propose to find the position in each constellation and fusion their results in a way that final position has the minimum possible variance instead of combining the constellations in a satellite level and dealing with inter system biases. Experimental studies are conducted based on IGS...
Attitude determination using double GPS receivers and gyro
, Article Proceedings of the IEEE Conference on Decision and Control, 17 December 2018 through 19 December 2018 ; Volume 2018-December , 2019 , Pages 583-588 ; 07431546 (ISSN); 9781538613955 (ISBN) ; Namvar, M ; Yazdanpanah, M. J ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2019
Abstract
This paper presents an asymptotically-convergent nonlinear attitude estimator for rigid bodies using a rate gyro and GPS. Double-difference carrier phase measurement are provided by at least two GPS antennas. The unknown integer ambiguity factor related to GPS carrier phase measurement is estimated along with the attitude. An observability condition is derived to guarantee convergence of the estimator when a single baseline vector is available with more than four satellites in view. Finally, experimental test from a survey boat illustrates performance of the proposed observer. © 2018 IEEE
Emergency SMS
, Article 2006 SICE-ICASE International Joint Conference, Busan, 18 October 2006 through 21 October 2006 ; 2006 , Pages 1139-1142 ; 8995003855 (ISBN); 9788995003855 (ISBN) ; Sharif University of Technology
2006
Abstract
Delivering first aid before transferring patients to hospital is among keys to survival. Moreover, calling the emergency center as soon as possible and providing brief information about the patient are helpful for the emergency center to dispatch specialized medical team and equipments proportionate to the conditions of the patient. Mobile phone is a device which many people use and always carry with them. One more thing is that SMS (Short Message Service) stands as a favorite service in mobile network, used to exchange short messages and featuring low cost, non-stop lines of dispatch, possibilities for offline work and so forth. This paper puts forward procedures of calling an emergency...
Probability of collision and risk minimization of orbital debris on the Galileo satellite constellation
, Article Science and Technology Series ; Volume 109 , 2005 , Pages 247-258 ; 02784017 (ISSN) ; Bahrami, M ; Sharif University of Technology
2005
Abstract
Satellite-based navigation has rapidly evolved into an efficient tool extensively used in a wide variety of civilian applications covering numerous modes of transportation, communication, administration, geodesy, agriculture, etc. The current systems globally available are the US Global Positioning System (GPS) and the conceptually very similar Russian Global Navigation Satellite System (GLONASS). The European Union (EU) has also decided to press ahead with plans to develop Galileo system, a European version of the Global Positioning System (GPS) after the system definition during 1999/2000. The development phase of Galileo is expected to run from 2002 to 2005 with a deployment phase,...
Cell Phones Network Data Analysis and Travel Time Prediction Based on Geographical Data of Network
, M.Sc. Thesis Sharif University of Technology ; Habibi, Jafar (Supervisor)
Abstract
Our surrounding environment has valuable information about our life. We live in technological societies where we are leaving digital footprints in, continuously. Growing development and popularity of mobile phones, has turned them into the most important global sensors. Mobile phone tracking via GPS points is one of the data types which can be collected from these sensors and used for traffic monitoring, intelligence traffic control and travel time estimation.
In order to use these devices, we need to collect data, detect transportation mode and estimate travel time. By evaluation of previous works, we can feel the need to a comprehensive approach for detecting transportation mode of...
In order to use these devices, we need to collect data, detect transportation mode and estimate travel time. By evaluation of previous works, we can feel the need to a comprehensive approach for detecting transportation mode of...
Investigation of Saturation Dynamics in GPS Allocated Orbits for Removal and Injection Mission
, M.Sc. Thesis Sharif University of Technology ; Fathi, Mohsen (Supervisor) ; Malaek, Mohammad Bagher (Supervisor)
Abstract
The number of GPS satellites, which are spent their life and work, have been increasingly on the rise. Hence with knowledge of debris numbers, we can get an estimate of collisions risk probability and functional interference of active satellites in the future time. In this study, by using three methods, least-squares, RBF and ANFIS and statistical data the growth pattern of retired satellite numbers has been expected in the future. Numbers estimated by curve fitting methods in 2014 have been compared to the number of satellites disabled and growth estimation error has been analyzed by two models. Solar activity, the sun's radiation incidence angle on the satellite solar panel and the Earth's...
Offline Map-Matching for GPS Observations
, M.Sc. Thesis Sharif University of Technology ; Abam, Mohammad Ali (Supervisor)
Abstract
Location observations from Global Positioning System (GPS) loggers are an important source of data for travel behavior researchers. Using GPS, requires a receiver, a digital map and a software that matches the user logged positions to the map. Identifying the location of the GPS data points on a coded map of the transportation network is not a trivial process. There is always an error in calculating the coordinates obtained from the GPS satellites, and also the available maps are not accurate enough. As a result, map-matching always carries some errors. Thus, different algorithms to do this mapping more precisely are presented. The output of the map-matching process is the identification of...
Target Detection and Tracking in Passive Forward Scattering Radar based on Satellite Signals
, M.Sc. Thesis Sharif University of Technology ; Behroozi, Hamid (Supervisor)
Abstract
In this thesis, we investigate a passive forward scattering radar system based on satellite signal. In this thesis we have used the GPS satellite signal as a non-cooperative transmitter.In order to analyze the passive forward scattering radar system as a subset of the bistatic radars, first the features and equations of the bistatic radar will be presented, and then we will discuss the important advantages and disadvantages of the passive forward scattering radar.In order to investigate the features of passive forward scattering radar based on satellite signal, an appropriate geometry will be presented with the characteristics of this radar and parameters such as time delay between direct...
Multisystem Global Navigation Satellite System Receiver
, M.Sc. Thesis Sharif University of Technology ; Fotowat Ahmady, Ali (Supervisor)
Abstract
Nowdays, Navigation sattelite systems are playing critial role in human life. In many equipments such as cell phone, transmitters , transportation systems ,etc. Accurate and reliable navigation is needed.
GPS was the first navigation sattelite system but today rival nations have delevoped or are developing parallel systems. These systems are Glonass operated by Russisa, Galileo by Europe and Beidou By china. GPS can not suffice human needs alone so the proposed solution is to exploit all above mentioned altenative systems. In this case, we can achieve higher accuracy, lower navigation time and more reliable navigation.
In this thesis the receiver is designed to receive all above...
GPS was the first navigation sattelite system but today rival nations have delevoped or are developing parallel systems. These systems are Glonass operated by Russisa, Galileo by Europe and Beidou By china. GPS can not suffice human needs alone so the proposed solution is to exploit all above mentioned altenative systems. In this case, we can achieve higher accuracy, lower navigation time and more reliable navigation.
In this thesis the receiver is designed to receive all above...
Real Time Location Finding for Vehicles in Transport Systems
, M.Sc. Thesis Sharif University of Technology ; Hemmatyar, Afshin (Supervisor)
Abstract
In mobile ad hoc networks, having an efficient routing protocol to deal with dynamics in network topology, based on the user behavior learning, has a significant role in generating more accurate results. It is valuable to use a realistic mobility model in such networks so that the results from the simulation will reflect the actual reaction of mobile nodes in the real world. Using a realistic mobility model helps simulation to have more accurate results in comparison with other kinds of mobility models especially in a Vehicular Ad hoc Network (VANET). Before exchanging information between moving vehicles, the destination node should be located. However, the existing location service...
A 1-mW current reuse quadrature RF front-end for GPS L1 band in 0.18μm CMOS
, Article 2012 19th IEEE International Conference on Electronics, Circuits, and Systems, ICECS 2012, Seville, Seville, 9 December 2012 through 12 December 2012 ; 2012 , Pages 157-160 ; 9781467312615 (ISBN) ; Fotowat Ahmady, A ; Jenabi, M ; Sharif University of Technology
2012
Abstract
A new low-power current reuse topology is proposed for the GPS receiver's RF front-end that combines the higher conversion gain and suppressed noise figure characteristics of cascade structures with the low power consumption of stacked architectures. The presented circuit, called 1.5-stage LMV cell, consists of LNA, Mixer and VCO (LMV) in such a formation that boosts LNA gain and suppresses mixer's noise figure by cascading the two stages while reusing their currents in the two stacked quadrature VCOs and placing the mixer's upper tree switches at the vicinity of on-off regions. The circuit is designed and its layout is generated in TSMC 0.18μm CMOS technology. Post-layout simulations using...
A low-power current reuse CMOS RF front-end for GPS applications
, Article 2011 IEEE International RF and Microwave Conference, RFM 2011 - Proceedings, 12 December 2011 through 14 December 2011, Seremban ; 2011 , Pages 416-419 ; 9781457716294 (ISBN) ; Fotowat Ahmady, A ; Sharif University of Technology
Abstract
A very low-power RF front-end based on a new current reuse QLMV cell (Quadrature VCO-LNA-Mixer) is proposed for GPS applications. The front-end, designed in 0.18μm CMOS technology, provides improved performance characteristics while consuming only 1 mA current. Simulation results are presented and compared with recently published works in the field
Error reduction of a low cost GPS receiver for kinematic applications based on a new kalman filtering algorithm
, Article International Journal of Innovative Computing, Information and Control ; Volume 6, Issue 8 , 2010 , Pages 3775-3786 ; 13494198 (ISSN) ; Refan, M. H ; Sharif University of Technology
2010
Abstract
Positioning for kinematic applications is of great importance in terms of accuracy and computational complexity. In this paper, we present an algorithm based on correlation between error components in three directions, i.e. Δx, Δy, Δz to decrease positioning error of a GPS receiver for kinematic applications. The main feature of proposed algorithm is that it modifies data at each instant and in each direction using data of two other directions at the same instant (i.e. some sort of online modification). This feature was acquired using an approach introduced to model state transition matrix using AR coefficients of two other directions. The algorithm was implemented on the output raw position...
Determination of ship maneuvering hydrodynamic coefficients using system identification technique based on free-running model test
, Article Scientia Iranica ; Volume 23, Issue 5 , 2016 , Pages 2154-2165 ; 10263098 (ISSN) ; Seif, M. S ; Mehdigholi, H ; Sharif University of Technology
Sharif University of Technology
2016
Abstract
In the recent years, different mathematical models have been suggested for maneuvering of displacement vessels that are capable of estimation of vessel maneuvers with acceptable precision. These mathematical models are based on determined hydrodynamic coefficients and their accuracy depends on the known coefficients used to solve the mathematical model. System identification methods are developed to calculate these coefficients utilizing input and output data obtained from different sources. In this research, a 4.36-m model of KRISO Container Ship (KCS) displacement vessel has been manufactured by fiberglass, and the maneuver turning tests have been carried by self-propulsion method. A...
Nonlinear asymptotic attitude estimation using double GPS receivers and gyro
, Article IEEE Transactions on Control Systems Technology ; Volume 28, Issue 4 , July , 2020 , Pages 1579-1585 ; Namvar, M ; Yazdanpanah, M. J ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2020
Abstract
We present an asymptotically convergent nonlinear attitude estimator using a rate gyro and GPS. Double-difference (DD) carrier phase measurements are provided by at least two GPS antennas. The unknown integer ambiguity factor related to GPS carrier phase measurement is estimated along with the attitude. An observability condition is derived to guarantee the convergence of the estimator when a single baseline vector is available with more than four satellites in view. A systematic procedure for tuning observer parameters is also presented. Finally, the experimental test from a light fixed-wing aircraft illustrates the performance of the proposed observer. © 1993-2012 IEEE
Design and simulation of an off-line internal navigation system for pipeline inspection applications
, Article ASME International Mechanical Engineering Congress and Exposition, IMECE 2007, Seattle, WA, 11 November 2007 through 15 November 2007 ; Volume 9 PART A , 2008 , Pages 521-526 ; 0791843033 (ISBN); 9780791843031 (ISBN) ; Nabi, A ; Fazeli, A ; Sharif University of Technology
2008
Abstract
The aim of this paper is to design an inertial navigation system (INS) for use in a geometry pipe inspection gauge, capable of measuring pipeline movements and producing the line's 3D map with a reasonable accuracy. A suitable reference path was generated as a design platform. Solving the navigation equations and compensating for the errors, by using extended Kaiman filter (EKF) approach, the INS path was generated and its position errors in all three directions were considered. Divergence problems due to far apart GPS position observations, was overcome by defining suitable threshold for the variances of the estimated errors. Copyright © 2007 by ASME