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Lokacijsko označevanje meritev se uporablja za zajem prostorskih podatkov. Z večanjem dostopnosti ustreznih tehnologij je teh vedno več, pogosto pa so tudi javno objavljeni. Lokacijsko označene meritve nam pomagajo razumeti prostor okoli nas in pojave v njem. Najpogostejši način pridobivanja točne lokacije na Zemlji danes je uporaba globalnih satelitskih navigacijskih sistemov (GNSS). Sprejemniki so z razvojem postali dovolj zmogljivi, majhni in lahki, da jih lahko namestimo tudi na manjši brezpilotni letalnik. Novejše različice sprejemnikov GNSS z uporabo raznih metod omogočajo zanesljivo določanje lokacije na Zemlji z natančnostjo v območju centimetrov. Na brezpilotni letalnik lahko hkrati priklopimo razna tipala in z mikrokrmilnikom ter nekaj programske opreme zajemamo meritve, katerim kot metapodatek dodamo lokacijo zajema. Meritve lahko kasneje obdelamo in prikažemo na različnih grafih in zemljevidih. Magistrska naloga se ukvarja z razvojnim procesom in evalvacijo brezpilotne letalne platforme za zajem lokacijsko označenih meritev. Na začetku opisuje osnove koordinatnih sistemov ter v grobem predstavi delovanje GNSS in uporabo popravkov za natančno ugotavljanje lokacije na Zemlji. V drugem delu predstavi in opiše izgradnjo brezpilotnega letalnika kot preizkusne platforme za izvajanje lokacijsko označenih meritev. V tretjem delu je opisanih nekaj poskusnih letov, izvedene so meritve višinskih podatkov ter evalvacija natančnosti ugotavljanja lokacije z GNSS in drugimi metodami. Na koncu je prikazanih nekaj poskusnih meritev smernega diagrama različnih anten z obletavanjem. Location tagging is used to measure spatial data. The amount of data is increasing with technology accessibility and it is often publicly available. Location-tagged measurements help us understand the phenomena happening around us. The most common way of determining location on Earth nowadays are global navigation satellite systems (GNSS). Recent advances in technology made it possible for receivers to be very small, light and inexpensive, as well as achieve accuracies in the centimetre range. An unmanned aerial vehicle (UAV) can be equipped with such receivers and different sensors to take location-tagged spatial measurements. The data can then be processed and shown on different charts and maps. The thesis addresses the development process and evaluation of an unmanned aerial platform for capturing location-tagged measurements. In the beginning, the basics of coordinate systems and location determining on Earth are presented. The second part explains the basics of UAVs and the process of building one for capturing location-tagged measurements. The third part describes the flight testing process and evaluates the height and position measurement accuracy using GNSS and other methods. The last part presents some test measurements of the radiation patterns of different antennas.

Kinematična določitev položaja z GNSS danes vse bolj pridobiva na pomenu, v geodeziji zaradi direktnega pozicioniranja daljinsko vodenih letalnikov, izven geodezije pa tudi zaradi razvoja samovozečih vozil. Več kot očitno je, da senzorski sistemi, ki uporabljajo samo tehnologijo GNSS, niso primerni za uporabo v hitro spreminjajočem se okolju vozila. V dani nalogi nas je zanimalo, v katerih situacijah se dogodijo težave pozicioniranja in koliko različnih sistemi potrebujejo, da lahko ponovno določijo položaj ustrezne kakovosti. Izmero na širšem območju Ljubljane smo naredili z dvema metodama, z določitvijo položaja v realnem času (angl. Real-Time-Kinematic -RTK) in z naknadno obdelavo (angl. Post-Processing Kinematic), pri čemer smo uporabili tri sprejemnike Leica dveh serij, in sicer: Leica GS15 in Leica GS18T. Instrumente smo postavili na streho avtomobila in se peljali po vnaprej določeni trasi, ki je vsebovala različne ovire (podvozi, tuneli, gozd, visoke zgradbe itd.). Opazovanja smo obdelali s komercialno programsko opremo Leica Inifinity in odprtokodno opremo RTKlib. Analizirali smo rezultate in ugotovili, da ne moremo trditi, da v enakih pogojih uporaba različnih instrumentov vodi do enakih rezultatov. Enako velja tudi za primerjavo med metodami izmere. Tekom raziskave smo ugotovili, da so bile naknadno obdelana opazovanja s programskim paketom Leica Inifinity precej bolj skladna s položaja, določenimi z RTK-metodo izmere, proti položajem, ki smo jih pridobili z uporabo programskega paketa RTKlib. Dano raziskavo bi lahko v prihodnje nadaljevali z oceno kakovosti meritev, ki jih pridobimo z integriranimi GNSS/INS senzorji, ki omogočajo določitev položaja tudi v času izgube signalov GNSS. Kinematic GNSS positioning is becoming increasingly important today, both in surveying through direct positioning of UAVs (Unmanned Aerial Vehicles) and in navigation through the development of autonomous driving vehicles. It is more than obvious that sensor systems using only GNSS technology are not suitable for use in the rapidly changing vehicle environment. In a specific task, we were interested in the situations in which position determination problems occur and how many different systems are required to determine a position with reasonable quality. We performed two methods of position determination in the Ljubljana area, Real-Time Kinematic (RTK) and Post-Processing Kinematic (PPK), using three Leica receivers from two series, the Leica GS15 and the Leica GS18T. The instruments were placed on the roof of a car and driven along a predefined route with various obstacles (underpasses, tunnels, forests, tall buildings, etc.). The observations were processed using the commercial software Leica Inifinity and the open-source software RTKlib. The results were analyzed and it was found that it cannot be said that using different instruments under the same conditions will give the same results. The same is true for the comparison between the surveying methods. During the study, we found that the observations post-processed with the Leica Inifinity software package matched the positions determined by the RTK survey method much better than the positions determined with the RTKlib software package. The present study could be continued in the future by evaluating the quality of measurements with integrated GNSS/INS sensors, which allow positioning even when GNSS signals are lost.

Direktno georeferenciranje daljinsko vodenih letalnikov (angl. Unmanned Aerial Vehicle, UAV) se je v zadnjih letih izpopolnilo z vgrajenimi moduli izmere RTK (angl. Real-Time Kinematic) in PPK (angl. Post-Processed Kinematic), ki omogočajo določitev položaja v realnem času ali naknadno. Obe metodi imata svoje prednosti in slabosti, a se hkrati dopolnjujeta, ko ene izmed njiju zaradi različnih situacij (npr. lastnosti terena, ne/dostopnost mobilnega omrežja …) ni mogoče uporabiti. V raziskavi smo preizkušali letalnik Phantom 4 RTK na območju Strunjanskega klifa ob slovenski obali Jadranskega morja. Testno območje je zajemalo več snemalnih misij, katerih položaje smo določili v realnem času z navezavo na bazno postajo D-RTK 2 Mobile Station in naknadno na osnovi opazovanj GNSS z lastnih referenčnih baznih postaj v bližini snemanja. Položaje projekcijskih centrov posnetkov, pridobljene z metodama RTK in PPK, smo med sabo primerjali. Na podlagi koordinatnih razlik smo ugotavljali, ali različne lokacije baznih postaj vplivajo na kakovost rešitve PPK in ali se slednja značilno razlikuje od rešitve RTK. V članku je predstavljena tudi problematika obdelave PPK. Rezultati kažejo, da izbira lokacije bazne postaje lahko vpliva na kakovost določitve položaja UAV. Koordinatne razlike med rešitvami RTK in PPK v povprečju znašajo 0,3–8 cm v smereh E in ^ ter 1–6 cm v smeri ^. In recent years, direct georeferencing of Unmanned Aerial Vehicles (UAVs) has been perfected with built-in Real-Time Kinematic (RTK) and Post-Processed Kinematic (PPK) measurement modules, which enable real-time or subsequently positioning. Both methods have their advantages and disadvantages, but at the same time they complement each other when one of them cannot be used due to different situations (eg terrain characteristics, non / accessibility of the mobile network …). In the research, we tested the Phantom 4 RTK aircraft in the area of the Strunjan cliff along the Slovenian coast of the Adriatic Sea. The test area included several recording missions, the positions of which were determined in real time by connecting to the D-RTK 2 Mobile Station and subsequently based on GNSS observations from our own reference base stations in the vicinity of the survey. The positions of the projection centers of the images obtained by the RTK and PPK methods were compared with each other. Based on the coordinate differences, we determined whether different locations of base stations affect the quality of the PPK solution and whether the latter differs significantly from the RTK solution. The article also presents the issue of PPK processing. The results show that the choice of base station location can affect the quality of UAV positioning. The coordinate differences between the RTK and PPK solutions average 0.3–8 cm in the ^ and ^ directions and 1–6 cm in the ^ direction.

Ideja magistrske naloge je bila, da zgradimo delujoč nizkocenoven GNSS-sistem za nadgradnjo starejšega letalnika Phantom 4 Pro za namene direktnega georeferenciranja. V nalogi smo uporabili nizkocenoven sprejemnik GNSS, ZED-F9P, katerega delovanje smo ga testirali na površju in na letalniku. Testirali smo ga pri metodi izmere v realnem času (ang. real time kinematic – RTK) in metodi naknadne obdelave kinematičnih opazovanj GNSS (angl. post-processing kinematic – PPK). Pri poskusih na tleh smo koordinate zakoličenih točk najprej primerjali s koordinatami, pridobljenimi z nizkocenovnim sprejemnikom. Da bi ocenili točnost določitve koordinat točk trajektorije leta, smo letalnik opremili s 360° mini prizmo in izbranim točkam določili koordinate tudi s klasično terestrično izmero. Natančnost določitve koordinat na tleh in med letom v zraku je bila pri obeh kinematičnih metodah (RTK in PPK) manj kot 2 cm. Pri vseh štirih poskusih je točnost določitve koordinat za obe metodi PPK in RTK znašala manj kot 3 cm za horizontalni komponenti položaja in manj kot 6 cm za višino. Rezultati vzpostavljenega sistema kažejo, da lahko brezpilotne letalnike precej dobro nadgradimo s senzorji za pozicioniranje in spremljanje zasukov letalnika. V prihodnje bo potrebno razrešiti še problematiko časovne uskladitve fotografskih posnetkov in ostalih senzorjev na letalniku. In this master thesis, we pursued the idea of building a low-cost GNSS system and upgrading older Phantom 4 Pro aircraft for direct georeferencing purposes. In the thesis, a low-cost GNSS receiver ZED-F9 was tested both on the ground and on the aircraft. The receiver was tested using the real-time kinematic (RTK) and in post-processing kinematic (PPK) method. In the ground tests, the reference coordinates of the staked out points were compared first with the coordinates obtained using the low-cost GNSS receiver. To determine the flight trajectory position accuracy, a 360° mini prism was attached to the aircraft, which was measured using the classical terrestrial method. The accuracy of the determined coordinates, on the ground and on the aircraft, was less than 2 cm for both kinematic methods (RTK and PPK). In all four experiments, the position accuracy for the PPK and RTK methods was below 3 cm for horizontal components and less than 6 cm for the altitude. The results of the built low-cost GNSS system show that unmanned aerial vehicles can be quite well upgraded with sensors for positioning and monitoring aircraft rotations. In the future, it will be necessary to resolve the issue of time synchronisation of photographs and other sensors on the aircraft.

V diplomskem delu predstavljamo postopek načrtovanja in izdelave naprave za določanje lokacije, ki z uporabo tehnologij GNSS (ang. Global Navigation Satallite System) in RTK (ang. Real-time kinematic) omogoča izmero položaja merilnika z globalno napako pod 10 cm. V ta namen najprej predstavimo ustrezne protokole in uporabljene tehnologije. V nadaljevanju se osredotočimo na izbor komponent ter potek načrtovanja in izdelave same naprave. Na koncu predstavimo še izvedene teste, s katerimi smo prikazali natančnost sistema. This thesis describes the design and realization of a device that, based on Global Navigation Satallite System (GNSS) and Real-time kinematic (RTK) technologies, allows for providing global location information with less than 10cm accuracy. We first describe protocols and technologies used for this purpose. Next, we focus on components, design process, and the implementation of the positioning device. Finally, validation protocol and the accuracy assessment are described.

V nalogi smo obravnavali kakovost podatkov in produktov, ki jih zagotavlja državno GNSS omrežje SIGNAL. Preizkuse smo izvedli na treh deloviščih, ki so obsegala virtualno mrežo točk, z generiranimi opazovanji v obliki VRS, delovišče na Krvavcu ter delovišče na območju Avtosejma v Ljubljani. Preizkušali smo različne vplive na opazovanja in kakovost določitve koordinat točke. Zanimal nas je vpliv dolžine baznega vektorja, višinske razlike med bazno točko in roverjem, časa trajanja opazovanj in smeri baznega vektorja med bazno in novo točko. Dodatno nas je zanimal tudi vpliv nadmorske višine delovišča ter nadmorske višine VRS, na deloviščih Krvavec in Avtosejem smo analizirali tudi kakovost relativnih koordinat med točkami. In this thesis we dealt with the quality of data and products provided by the national GNSS network SIGNAL. The tests were carried out at three sites comprising a virtual grid of points with generated observations in the form of a VRS, a site on Krvavec and a site in the Avtosejem area in Ljubljana. We tested different influences on observations and the quality of point coordinates. We were interested in the influence of the length of the base vector, the height difference between the base point and the rover, the duration of the observations and the direction of the base vector between the base and the new point. We were additionally interested in the influence of the elevation of the site and the altitude of the VRS. At the Krvavec and Avtosejem work sites we also analyzed the quality of the relative coordinates between the points.

Magistrsko delo »Vpliv natančnosti koordinat oslonilnih točk na fotogrametrične izdelke« zajema določitev koordinat fotogrametričnim oslonilnim in kontrolnim točkam z različnimi metodami izmere GNSS. Terenska izmera je obsegala večurno statično izmero GNSS, več ponovitev RTK-metode izmere ter prelet območja z daljinsko vodenim zrakoplovom. Opazovanja večurne statične izmere smo obdelali na več načinov, in sicer tako, da smo spreminjali minimalni višinski kot sprejema signala GNSS in modele troposferske refrakcije, uporabili različne efemeride, se navezali na različne stalne postaje GNSS ter uporabili opazovanja različnih dolžin. Položaje točk, pridobljene z obdelavo večurne statične izmere, smo primerjali s položaji, določenimi z RTK-metodo izmere. Položaje točk, pridobljene z relativno obdelavo statične izmere GNSS, smo primerjali s položaji, ki smo jih določili z absolutno metodo določitve položaja PPP z različnimi spletnimi aplikacijami. Vhodni podatek za fotogrametrično obdelavo, v kateri so bili izdelani fotogrametrični oblaki točk, DMR-ji ter ortofoti, so bile fotografije študijskega območja, posnete z daljinsko vodenim zrakoplovom, ter koordinate oslonilnih točk, določene z metodami izmere GNSS različne kakovosti. Fotogrametrične izdelke smo izdelali v programu 3Dsurvey, analizirali smo jih tako, da smo ocenili njihovo točnost na dva načina. Za oceno absolutne točnosti izdelkov smo uporabili oslonilne točke dolge statične izmere GNSS kot kontrolne točke, za relativno oceno točnosti pa smo izvedli primerjavo z referenčnimi izdelki. The master's thesis entitled »Influence of the quality of ground control point coordinates on photogrammetric products« covers the definition of coordinates for photogrammetric ground control points and control points using different of GNSS methods. The field measurements included a GNSS static measurement lasting several hours, several repetitions of RTK measurements and a flight over the area with a remote-controlled aircraft system. The observations of the several-hour static measurement were analysed with different parameters – changing minimal elevation angles, models of tropospheric refraction, by using different ephemerides, linking to different continuously operating GNSS reference stations and using observations of different occupation durations. The positions of the points obtained by analysing the several-hour static measurement were compared with the positions defined by the RTK method. The positions of the points obtained from a relative analysis of the GNSS static measurement were compared with the positions defined by the precise point positioning (PPP) absolute method with different web applications. The input data for photogrammetric analysis in which the photogrammetric point clouds, DSMs and orthophotos were made, were the photographs of the study area, taken by the remote-controlled aircraft system, and the coordinates of the ground control points, defined by the GNSS methods of measurement of different accuracies. The photogrammetric products were produced in the program 3Dsurvey and analysed by assessing accuracy in two ways. In order to evaluate the absolute accuracy of the products, we used points, fixed with GNSS static measurement lasting several hours as a control point, the relative accuracy was made by comparing the reference products.

Vsako leto se izvede nekaj izstrelitev novih satelitov v različnih globalnih navigacijskih satelitskih sistemih (GNSS) z namenom izboljšanja globalne pokritosti z navigacijskim satelitskim signalom. To hkrati omogoča tudi, da določitev položaja z uporabo sistemov GNSS postaja vedno bolj uporabljana tehnika v različnih aplikacijah določitve položaja. GNSS omogoča določitev položaja visoke točnosti in natančnosti v realnem času z visoko hitrostjo izvajanja meritev in sicer 1 Hz ali celo 10 Hz. Ta lastnost je zelo zaželena pri projektih stalno potekajočega monitoringa, zato GNSS monitoring postaja vedno bolj uporabljan pristop. GNSS monitoring se običajno izvaja z uporabo tehnik diferencialnega GNSS. Tako je bil namen te raziskave ovrednotiti in primerjati rezultate določitve položaja v realnem času z uporabo tehnik diferencialnega GNSS ter podatkov opazovanj različnih kombinacij frekvenc in različnih sistemov GNSS. Za namen raziskave je bil nad 14 dnevnimi seti eno- in dvofrekvenčnih opazovanj GNSS, pridobljenih s treh GNSS sprejemnikov, ki so tvorili dva, 51 in 13 990 metrov dolga, bazna vektorja, izveden večkratni preračun določitev položaja v realnem času. Ti seti so vsebovali opazovanja GNSS sistemov GPS, GLONASS in BeiDou, med katerimi je bilo mogoče narediti sedem različnih kombinacij. Serije koordinat določitev položaja v realnem času, ki so bile izračunane na podlagi vseh kombinacij med sedmimi kombinacijami sistemov GNSS, opazovanji dveh frekvenc in dveh dolžin baznih vektorjev, so bile analizirane in primerjane med sabo. Naloga se zaključi z razpravo o rezultatih opravljene raziskave, ki so predstavljeni v obliki različnih grafičnih prikazov in statističnih indikatorjev. Ugotovitve pokažejo razliko v rezultatih ob uporabi različnih sistemov GNSS ločeno ali kombiniranja med njimi. Kot samostojen sistem se za najbolj točnega izkaže GPS, med tem ko kombinacija vseh treh sistemov GNSS vrne najboljše numerične vrednosti rezultatov. With new satellites of different Global Navigation Satellite Systems being launch every year in order to improve global positioning coverage, GNSS positioning is becoming a more and more used technique for various applications where position is needed. One of its abilities is to provide high accuracy and high precision coordinates in real time with a very high positioning rate of 1 Hz or even 10 Hz. This is a very desired condition in monitoring projects, thus GNSS monitoring is becoming used more often in continuous monitoring applications. GNSS monitoring is usually done by applying differential GNSS techniques. Therefore, the purpose of this research was to evaluate and compare long term differential GNSS real time positioning results obtained by using different GNSS and frequency combinations. Single- and dual frequency real time positioning of two, 51 and 13990 metre long baselines were computed several times using 14 day GNSS data sets from three GNSS receivers. These data sets included observations of GPS, GLONASS and BeiDou navigation satellite systems, which resulted in seven different GNSS combinations. Real time positioning coordinate series of all combinations between seven GNSS combinations, two frequencies and two baseline lengths were then analysed and compared to one another. The thesis ends with discussion about the results of this analysis, which are presented through various plots, histograms and statistical indicators. Findings show differences in results when using each GNSS separately or in different combinations. As a standalone system GPS proved to be the most accurate, while the combination of all three GNSS gave the best numerical results.

V nalogi predstavljamo vzpostavitev geodetske mreže šestih točk za preizkus instrumentov GNSS-RTK. Za delovišče smo izbrali lokacijo ljubljanskega avtosejma. Cilj naloge je bil pridobiti koordinate trajno stabiliziranih točk v oddeljanosti le nekaj metrov. V nalogi predstavljamo tudi teoretična izhodišča in praktično izvedbo preizkusa GNSS-RTK instrumentov po standardu ISO 17123-8. Preizkusili smo instrumenta JAVAD TRIUMPH-LS in Leica Viva GS15. Dodana vrednost vzpostavitve danega delovišča je v možnosti, da lahko hkrati naredimo preizkus treh instrumentov GNSS-RTK in ugotovimo, ali z različnimi instrumenti v enakih pogojih dobimo primerljive rezultate. This thesis presents a process of geodetic network establishment for testing GNSS-RTK instruments. The worksite was located at the car fair in Ljubljana. The objective of the thesis was to get coordinates of points, stabilised within a few meters. Moreover, we present theoretical background as well as practical tests of GNSS-RTK instruments according to ISO 17123-8 standard. Two instruments, namely JAVAD TRIUMPH-LS and Leica VIVA GS15, were included into tests. The added value of the specific worksite is in possibility of testing three instruments simultaneously to find out and compare their operation under the same conditions.

V diplomski nalogi predstavljamo rezultate terenske izmere GNSS izven območja državnega omrežja stalnih postaj SIGNAL. Problematično območje pokritosti predstavlja celoten obmejni pas med Slovenijo in Italijo. Kakovost določitve koordinat smo preverili na dveh lokacijah v Italiji. Prvo delovišče je bilo izbrano v Trbižu in drugo pri Belopeških jezerih. Na vsaki lokaciji smo z dvema sprejemnikoma GNSS naredili statično izmero GNSS in RTK-metodo izmere. Opazovanja statične izmere GNSS smo naknadno obdelali v programu Leica Infinity z različnimi kombinacijami navezav na stalne postaje omrežja SIGNAL (Bovec, Radovljica in Beljak) in na začasno bazno točko, ki je vzpostavljena v Mojstrani. Cilj naloge je bilo prikazati kakovost določitve položajev točk z različnimi metodami GNSS na kritičnem območju omrežja SIGNAL, kjer VRS določijo z ekstrapolacijo. The thesis presents the results of field GNSS measurements outside the area covered by the SIGNAL network. The entire border region between Slovenia and Italy presents this type of a problematic area. For better representation of the measurements two locations in Italy were chosen for testing. The first worksite was in Tarvisio and the other at the Lakes of Fusine. At each location two GNSS receivers were set up and each receiver made a static GNSS and a RTK measurement. The static measurements were subsequently processed in the Leica Infinity programme using different combinations of connections to the permanent SIGNAL stations (Bovec, Radovljica and Villach) and a temporary basis point established in Mojstrana. The aim of this thesis was to demonstrate the quality of the determinating positions using the GNSS methods in the critical areas, where interpolation cannot be used for VRS.

V diplomski nalogi smo analizirali kakovost določitve položaja z metodo RTK v omrežju SIGNAL z uporabo različnih mrežnih konceptov in navezavo na eno referenčno postajo. Pri mrežnih konceptih smo uporabili koncept MAC (ang. Master-Auxiliary) in VRS (ang. Virtual Reference Station). Sama kakovost položaja je bila ocenjena na podlagi točnosti koordinat, katera je bila definirana kot razlika med referenčnimi koordinatami in koordinatami pridobljenimi z metodo RTK. Referenčne koordinate so bile pridobljene s statično metodo izmere GNSS. Kakovost metode RTK smo ocenili po standardu ISO 17123-8 po katerem smo tudi ocenili grobo pogrešene koordinate ter jih odstranili iz analiz. Preverili smo do kakšnih odstopanj v kakovosti položaja prihaja pri uporabi istega omrežja postaj GNSS s sprejemniki različnih proizvajalcev. Uporabili smo sprejemnike znamk Leica, Trimble in Javad. In this thesis, we analyzed the quality of position determination with the method of RTK in the Slovenian GNSS network SIGNAL. For position determination we used method RTK in various network concepts and using one reference station. We used network concept MAC (Eng. Master-Auxiliary Concept) and VRS (Eng. Virtual Reference Station). The quality of the position has been estimated based on the accuracy of coordinates, which was defined as the difference between the reference coordinates and the coordinates obtained by the method of RTK. Reference coordinates were obtained with GNSS static method. The quality of RTKmethod, was evaluated according to ISO 17123-8, for which we also estimated gross-errors in coordinates and removed them from the analysis. We analyzed the differences in the position quality, when we use the same network, but different GNSS receivers. We used Leica, Trimble and Javad receivers.