Global ETD Search

1	Performance Enhancement of Bearing Navigation to Known Radio Beacons / Prestandaförbättring av navigering efter bäring mot kända radiofyrar Erkstam, Erik, Tjernqvist, Emil January 2012 (has links) This master thesis investigates the performance of a car navigation system using lateral accelerometers, yaw rate and bearings relative three known radio beacons. Accelerometer, gyroscope and position data has been collected by an IMU combined with a GPS receiver, where the IMU was installed in the approximate motion center of a car. The bearing measurements are simulated using GPS data and the measurement noise model is derived from an experiment where the direction of arrival to one transmitter was estimated by an antenna array and the signal processing algorithm MUSIC. The measurements are fused in a multi-rate extended Kalman filter which assumes that all measurement noise is Gaussian distributed. This is not the case for the bearing measurement noise which contains outliers and therefore is modelled as a Gaussian uniform noise mixture. Different methods to deal with this have been investigated where the main focus is on the principle to use the Kalman filter’s innovation for each bearing measurement as an indication of its quality and discarding measurements with a quality above a certain threshold. navigation bearings-only outlier rejection MUSIC GPS EKF WGS84 RT90
2	Navigační systémy v geografických průzkumných akcích / Navigation in GIS Surveys Pop, Pavel January 2009 (has links) The project aims to design and implementation of navigation in GIS surweys. The system must be able to operate globally and deal with several types of navigation tasks in relation to the means of transport by which the navigation is carried out. One of the tasks is also to improve the course of navigation errors resulting from the removal of inaccuracies in the focus position and technical limitations of GPS, such as low frequency of the input data for guidance. Problems of low frequency of the input data is dealt with through the prediction of movement, which enabled the smooth display output users. Because it is not possible to completely test the system in operation, it created a simulation tool that lets you track the behavior of navigation in all situations. The document contains an analysis of the problem in terms of geography, the definition of the problems of orientation in space and their mathematical solution and an outline of implementation.
3	Development and Analysis of a Mobile Node Tracking Antenna Control System Hensley, Phillip H. 08 1900 (has links) A wireless communication system allows two parties to exchange information over long distances. The antenna is the component of a wireless communication system that allows information to be converted into electromagnetic radiation that propagates through the air. A system using an antenna with a highly directional beam pattern allows for high power transmission and reception of data. For a directional antenna to serve its purpose, it must be accurately pointed at the object it is communicating with. To communicate with a mobile node, knowledge of the mobile node's position must be gained so the directional antenna can be regularly pointed toward the moving target. The Global Positioning System (GPS) provides an accurate source of three-dimensional position information for the mobile node. This thesis develops an antenna control station that uses GPS information to track a mobile node and point a directional antenna toward the mobile node. Analysis of the subsystems used and integrated system test results are provided to assess the viability of the antenna control station. antenna control system communication motor power signal gps wgs84 Engineering, Electronics and Electrical Antennas (Electronics) Wireless communication systems. Global Positioning System.
4	Real Time Positioning; Construction and implementation of a GPS-Communicator. / Realtidspositionering; Utveckling av en GPS-kommunikator. Darnell, Christian, Wilczoch, Christian January 2002 (has links) The first half of the Masters thesis is the result of a survey made on the behalf of the Swedish company KORDAB International AB. The survey includes an overview of different positioning systems and some wireless communication techniques available on the market today. Positioning systems discussed are GPS, DGPS, AGPS and GSM positioning. Mobile Internet connections through mobile phones and communication through radio modems are mentioned and described as examples of wireless communication techniques. Examples of techniques described are HSCSD, GPRS, UMTS and MOBITEX. KORDAB is in the starting blocks to implement a real time positioning feature into their own technical information system GEOSECMA. This survey will give them a base which will help them to decide on which system to use for this feature. The second half of the thesis includes parts concerning a prototype made to exemplify how KORDAB could implement the real time positioning feature into GEOSECMA. The NMEA 0183 protocol, reference systems and transformation are described to give the necessary background knowledge for the construction and functionality of the prototype. The prototype is a GPS-communicator made as an interface between a GPS-receiver and GEOSECMA and its functionality is also described in this second half of the thesis. Feasible applications are also discussed to show the possibilities real time positioning gives. One application discussed is “Zoom and Auto highlighting”. This application is designed to help user of GEOSECMA to zoom in the map and highlighting the nearest object at current location. Reglerteknik GPS RTK DGPS AGPS GSM-positioning Real Time Positioning TOA TDOA EOTD AOA GSM HSCSD GPRS UMTS Mobitex NMEA 0183 GGA GSV WGS84 SWEREF99 RT90 GPS-Communicator Reglerteknik Automatic control Reglerteknik
5	Real Time Positioning; Construction and implementation of a GPS-Communicator. / Realtidspositionering; Utveckling av en GPS-kommunikator. Darnell, Christian, Wilczoch, Christian January 2002 (has links) <p>The first half of the Masters thesis is the result of a survey made on the behalf of the Swedish company KORDAB International AB. The survey includes an overview of different positioning systems and some wireless communication techniques available on the market today. Positioning systems discussed are GPS, DGPS, AGPS and GSM positioning. Mobile Internet connections through mobile phones and communication through radio modems are mentioned and described as examples of wireless communication techniques. Examples of techniques described are HSCSD, GPRS, UMTS and MOBITEX. KORDAB is in the starting blocks to implement a real time positioning feature into their own technical information system GEOSECMA. This survey will give them a base which will help them to decide on which system to use for this feature. </p><p>The second half of the thesis includes parts concerning a prototype made to exemplify how KORDAB could implement the real time positioning feature into GEOSECMA. The NMEA 0183 protocol, reference systems and transformation are described to give the necessary background knowledge for the construction and functionality of the prototype. The prototype is a GPS-communicator made as an interface between a GPS-receiver and GEOSECMA and its functionality is also described in this second half of the thesis. Feasible applications are also discussed to show the possibilities real time positioning gives. One application discussed is “Zoom and Auto highlighting”. This application is designed to help user of GEOSECMA to zoom in the map and highlighting the nearest object at current location.</p> Reglerteknik GPS RTK DGPS AGPS GSM-positioning Real Time Positioning TOA TDOA EOTD AOA GSM HSCSD GPRS UMTS Mobitex NMEA 0183 GGA GSV WGS84 SWEREF99 RT90 GPS-Communicator Reglerteknik Automatic control Reglerteknik

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