GPS technologies are more and more useful in sports today. Trainers can view athletic workout. There are many types of equipment that show how fast does sportsman move. So it’s very important to know if their parameters are enough accurate. That’s why these data must be analyzed. The main object about viewing athlete’s results is to get distance and moving speed. These two parameters can be shown from GPS data. To get distance from GPS parameters we need to use mathematical methods and carry out tests in various places. GPS speed parameter must be checked with standard and accurate device. This will be done with real bicycle speed. The analysis of athletic training methods must be also made.

El objetivo de este trabajo es analizar desde la mayor cantidad de aspectos posibles la técnica RTK, para luego obtener las respectivas conclusiones. Para cumplir con el objetivo propuesto se debió contar con una red de puntos con coordenadas geodésicas conocidas, la cual sirvió de base para las pruebas y mediciones que se hicieron con los equipos RTK. Por otro lado, se conformó una red de puntos con coordenadas geodésicas y planas locales con el fin de probar las funciones de replanteo con las que cuenta el equipo RTK y de comparar resultados de esta técnica con los de un levantamiento Stop and Go y con los de una Estación Total. Otro punto de importancia para la concreción del trabajo fue la zona elegida para llevar a cabo la experiencia, la cual debió guardar características variadas para analizar el comportamiento de las comunicaciones entre los receptores. Con el objeto de analizar las precisiones, el alcance, el comportamiento de la comunicación radial ante diversos terrenos y de comparar la técnica RTK con el método Estático, se diseñó una red de puntos en la zona de Punta Lara y Diagonal 74 que se midió en forma estática y con abundantes vectores redundantes. Posteriormente se realizó un ajuste de la red para darle mayor calidad a la posición de los puntos que la componían. Con esta red se podrá establecer la precisión real que pueden proporcionar los equipos RTK y además determinar si la misma es dependiente de la distancia entre la base y el móvil, o si depende en mayor medida de otros factores. Con el fin de efectuar comparaciones de resultados, el procesamiento de vectores y el ajuste de red se hicieron con programas de dos empresas: GPSurvey y TRIMNET, de la firma TRIMBLE (con la que se hicieron todas las mediciones) y GPPS y FILLNET, de la firma ASHTECH. A su vez, con cada programa se hicieron dos ajustes diferentes; uno con los vectores independientes de cada sesión solamente y otro con vectores dependientes. Esta segunda prueba también se hizo para encontrar diferencias entre ajustes. Con el objeto de dejar en claro algunos conceptos básicos de la medición con equipos GPS (Sistema de Posicionamiento Global), sistema en el que se apoyan los equipos RTK, se hará una breve descripción del mismo y se definirán conceptos propios y relacionados al mismo; aunque es necesario aclarar que este sistema de medición utiliza una gran cantidad de algoritmos que le dan cierta complejidad. / Trabajo final de carrera de la Facultad de Ingeniería (UNLP). Grado alcanzado: Ingeniero Agrimensor. Director de trabajo: Ricardo Soto; co-director de trabajo: Roberto Aldasoro.

El presente trabajo está orientado a la obtención de un modelo de alturas. Para la realización del mismo se propone analizar la aplicabilidad de cotas existentes; relevar y actualizar la información de organismos oficiales y completarla con coordenadas y altura respecto del piso. Se proyecta densificar la información con GPS, perfeccionando en la región el modelo que convierte alturas GPS en cotas sobre el nivel medio del mar y evaluar la incorporación de información altimétrica del modelo SRTM (Shuttle Radar Topography Mission) con una adecuada validación para zonas planas despobladas por ejemplo campos. La motivación para la realización de este estudio se basa en los objetivos planteados en un trabajo de cooperación con el grupo multidisciplinario que lleva adelante el proyecto PIT AP de la UNLP denominado “Efectos del Cambio Climático en las condiciones ambientales de un sector costero del Río De La Plata” que dirige el Dr. Eduardo Krusse.

Wireless sensor network technology has now been widely adopted. In many applications, distributed sensor nodes collect data at different locations and the location information of each node is required. The Global Positioning System is commonly used to identify the location of the nodes in such networks. Although GPS localization has consistent long-term accuracy, it is limited by the inherent dependency on a direct line of sight to 4 or more external satellites. The increasing demand for an embedded system providing reliable navigation solutions regardless of its operational environment has motivated investigations into the use of integrated systems that combine inertial sensors with GPS receivers. This research proposes a hardware architecture for location-based wireless sensor networks. In this architecture, each sensor node consists of a GPS receiver, a reduced set of low cost micro-electro-mechanical-system-based INS and a wireless transceiver. Sensor nodes in WSN are often equipped with irreplaceable batteries, which makes the power consumption crucial. To reduce the energy consumption, a microcontroller is used to control the power supply. Besides, a motion detection scheme is proposed by taking advantage of the ultra low-power wake-up function of the microcontroller. A low-power featured digital signal processor is used to accomplish the navigation computation using the Kalman filter for GPS/INS data fusion. Non-Holonomic Constraints derived velocity updates are applied to reduce the position errors. Field tests are conducted to verify the real-time performance of the proposed system with a positioning update rate of 20 Hz. The first test shows that the 2D INS/GPS integration can maintain the average system position error within 5 meters during a 60-second GPS outage. The second test used low cost inertial sensors. The average position error was 10.17 meters during a 20-second outage. The largest RMS value of position errors among these outages was within 14.5 meters. Furthermore, additional accuracy improvements of approximately 1.4 meters were achieved by utilizing NHC during GPS outages. The third test shows that the average error during a 30-second outage is approximately 20.6 meters for the on-foot scenario and 26.7 meters for the in-vehicle scenario. / Thesis (Master, Electrical & Computer Engineering) -- Queen's University, 2012-01-13 14:46:45.44

No description available.

A Global Positioning System (GPS) can be used to estimate an objects position,given that the object has a GPS antenna. However, the system requires informationfrom at least four independent satellites in order to be able to give a positionestimate. If two GPS antennas and a carrier-phase GPS measurement unit is usedan estimate of the objects heading can be calculated by determine the baselinebetween the two antennas. The method is called GPS Attitude Determination(GPSAD) and requires that an Integer Ambiguity Problem (IAP) is solved. Thismethod is cheaper than more traditional methods to calculate the heading butis dependent on undisturbed GPS-reception. Through support from an InertialMeasurement Unit (IMU), containing accelerometers and gyroscopes, the systemcan be enhanced. In Thorstenson [2012] data from GPS, GPSAD and IMU wasintegrated in an Extended Kalman Filter (EKF) to enhance the performance. Thisthesis is an extension on Thorstensons work and is divided into two separate problems:enhancement of positioning when less than four satellites are available andthe possibility to integrate the EKF with the search of the correct integers for theIAP in order to enhance the estimation of attitude. For both problems an implementationhas been made and the performance has been enhanced for simulateddata. For the first problem it has been possible to enhance the performance onreal data while that has not been possible for the second problem. A number ofproposals is given on how to enhance the performance for the second problemusing real data.

Reljefas yra trimatis, todėl turėtų būti taip ir vaizduojamas. Šiuolaikiniai reljefo modeliavimo programiniai paketai leidžia kurti naujus trimačius skaitmeninius reljefo vizualizavimo būdus, kurie yra lengviau suprantami vartotojų ir naudojami daugelyje sričių. Skaitmeninio reljefo modelio kūrimo procesas susideda iš duomenų rinkimo, modelio kūrimo ir jo vizualizacijos. Nedidelių teritorijų reljefo kartografavimui geriausia naudoti aukšto tikslumo GPS duomenis. Kuriant skaitmeninį reljefo modelį tikslinga pasirinkti tam tinkamiausią interpoliavimo metodą, atsižvelgiant į reljefo pobūdį, tinkamą metodo grafinę išraišką, atsirandančias paklaidas bei kompiuterio techninius parametrus, o vizualizacijai pasirinkti tokias modeliavimo priemones, kurios užtikrintų korektiško trimačio vizualizavimo praktiškumo, kartografinio dizaino, modeliavimo ir demonstravimo funkcijas bei naudoti tinkamus vizualizavimo būdus. Naudojantis SURFER 8 programa bei GPS duomenimis sukurtas Aukuro kalno piliakalnio skaitmeninis trimatis reljefo modelis. / The terrain surface is three-dimensional and should be treated like that. Modern 3D modelling computer programs allows to create new three-dimensional digital relief models, which are user-friendly and are used in many applications. Digital relief models creation process consist of data collecting, model making and it’s visualisation. For mapping small territories best method to collect data is GPS. When creating digital relief model, it is necessary to choose best interpolation method considering relief format, it’s graphics, standard deviation and computer technical parameters, and for visualisation choose such programs, which is capable to make correct three-dimensional practical, cartographical design, modelling and demonstrational functions as well as use right visualisation ways. Using SURFER 8 program and GPS data, Aukuras hill mound digital three-dimesional relief model was created.

No description available.

This research effort is concerned with the methods of simplified orbit determination and orbit representation and their applications for Low Earth Orbit (LEO) satellite missions, particularly addressing the operational needs of the FedSat mission. FedSat is the first Australian-built satellite in over thirty years. The microsatellite is approximately 50cm cubed with a mass of 58 kg. The satellite was successfully placed into a low-earth near-polar orbit at an altitude of 780km by the Japanese National Space Development Agency (NASDA) H-IIA launch vehicle on 14, December 2002. Since then, it has been streaming scientific data to its ground station in Adelaide almost daily. This information is used by Australian and international researchers to study space weather, to help improve the design of space computers, communication systems and other satellite technology, and for research into navigation and satellite tracking. This research effort addresses four practical issues regarding the FedSat mission and operations. First, unlike most satellite missions, the GPS receiver onboard FedSat operates in a duty-cycle mode due to the limitations of the FedSat power supply. This causes significant difficulties for orbit tracking, Precise Orbit Determination and scientific applications. A covariance analysis was performed before the mission launch to assess the orbit performance under different operational modes. The thesis presents the analysis methods and results. Second, FedSat supports Ka-band tracking experiments that require a pointing accuracy of 0.03 degree. The QUT GPS group is obligated to provide the GPS precise orbit solution to meet this requirement. Ka-band tracking requests satellite orbital position at any instant time with respect to any of the observation stations. Because orbit determination and prediction software only provide satellite orbital data at a discrete time point, it is necessary to find a way to represent the satellite orbit as a continuous trajectory with discrete observation data, able to obtain the position of the satellite at the time of interest. For this purpose, an orbit interpolation algorithm using the Chebyshev polynomial was developed and applied to Ka-band tracking applications. The thesis will describe the software and results. Third, since the launch of FedSat, investigators have received much flight GPS data. Some research was invested in the analysis of FedSat orbit performance, GPS data quality and the quality of the onboard navigation solutions. Studies have revealed that there are many gross errors in the FedSat onboard navigation solution (ONS). Although the 1-sigma accuracy of each component is about 20 m, there are more than 11 %positioning errors that fall outside +/-50m, and 5% of the errors are outside the 100mbound. The 3D RMS values would be 35m, 87m, and 173m for the above three cases respectively. The FedSat ONS uncertainties are believed to be approximately three times greater than those from other satellite missions. Due to the high percentage of outlier solutions, it would be dangerous to use these without first applying data detection and exclusion procedures. Therefore, this thesis presents two simplified orbit determination methods that can improve the ONS. One is the &quotgeometric method", which makes use of delta-position solutions derived from carrier phase differences between two epochs to smooth the code-based navigation solutions. The algorithms were tested using SAC-C GPS data and showing some improvement. The second method is the &quotdynamic method", which uses orbit dynamics information for orbit improvements. Fourth, the FedSat ground tracking team at Adelaide use the NORAD TLE orbit for daily FedSat tracking. Research was undertaken to convert an orbit trajectory into these Two Line Elements (TLE). Algorithms for the estimation of TLE solutions from the FedSat onboard GPS navigation solutions are outlined. Numerical results have shown the effects of the unmodelled forces/perturbations in the SPG4 models for the FedSat orbit determination would reach a level of ±1000m. This only includes the orbit representation errors with TLE data sets. The total FedSat orbit propagation should include both the orbit propagation and orbit representation terms. The analysis also demonstrates that the orbit presentation error can be reduced to ±200m and ±100mlevels with the EGM4x4 and EGM10x10 gravity field models respectively. This can meet the requirements for Ka-band tracking. However, a simplified tracking program based on numerical integration has to be developed to replace the SPG4 models.

Network-based Differential GPS (DGPS), regardless of its global, regional or local scales, is enabling technology to improve GPS positioning accuracy from tens of meters, to the levels of meters, decimetres and centimetres level in real time, depending on geographical coverage of the network and measurement types. The method is to use the data from a permanent network of reference stations to model errors due to inaccurate GPS satellite orbit ephemeris and clock data, ionospheric and tropospheric effects as well as other GPS satellite and receiver biases. Then error correction messages can be sent to users via any communication link in real time. This PhD research involves algorithm development for generating satellite orbit and tropospheric delay corrections using a regional or local reference network, especially tropospheric grid corrections, which have not been included in the existing DGPS correction vector messages, for the next generation of regional GNSS positioning services. Contributions of the research are made in the following three areas: First of all, research has been undertaken to test orbit interpolation methods, in order to represent GPS orbits and orbital corrections accurately and efficiently for (near) real-time GPS applications. For precise and predicted GPS orbits given in SP3 format and orbital corrections with respect to the broadcast ephemeris, numerical tests were conducted using different terms of Lagrange, Chebyshev and trigonometric polynomial functions. Secondly, this research has implemented a short-arc (9-hour) sliding-window orbit monitoring strategy to identify larger orbit errors in the predicted part of IGS ultra-rapid orbit solutions in near real time, using GPS tracking data from a regional network around Australia. The strategy is to predict the uncertainty estimates of each orbit over a short orbit arc in near real time, which allows users to down-weight the problematic satellites and reduces the effects of orbital errors for improved near real time ZTD estimation. Unlike long-arc orbit determination, we only estimate 6 orbital elements for each satellite. Finally, this research has proposed a new tropospheric delay correction model, which uses the Ordinary Kriging (OK) method to interpolate the residual ZTD within a regional area GPS network to improve the positioning accuracy. ZTD estimates from 129 EUREF Permanent Network (EPN) stations across Europe for over 3 months and from 17 GPSnet reference stations (Victoria, Australia) for one week were collected and processed for this study, respectively. It is concluded that interpolating residual ZTD is an efficient way to improve regional area differential GPS positioning.