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ŠUMARSKI LIST 7-8/2021 str. 74     <-- 74 -->        PDF

GNSS use in forest environment that is particularly challenging to the CORS-GNSS signal reception due to multipath and direct signal blockages, which significantly affect the signal processing and further degrade the position accuracy and availability. PPK method is very efficient yet in difficult situations we are going to encounter certain accuracy problems. Forest environments should also be classified under difficulty situations. In this study the most important criteria in PPK measurement technique are survey time and fixed of the integer ambiguity value. To raise measurement reliability there, results from different resolutions of ambiguities should be used on each point. This would enhance survey reliability and accuracy. Nonetheless, it appears that forest measurements with ± 1 cm accuracy cannot be guaranteed on all occasions, since difficult situations may lead to greater errors for this study (about ± 0-10 cm accuracy for horizontal components and about ± (0-100) cm accuracy for vertical components).
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