| Abstract [eng] |
Unmanned Arial Vehicles (UAV) utilize GNSS receivers as the main navigation instrument, in ideal conditions receiver works sufficiently well to ensure safe operation of a UAV. In recent years application fields of UAVs are expanding, and more often, they are used in environments with various interference to GNSS signals. One of the most common interference sources is a reflection from buildings in urbanized territories, which decreases performance often GNSS receiver correlator, which degrades the performance of receiver. In recent decades array processing has been adopted to suppress interference. This work created a GNSS receiver, which can attenuate reflection interference by utilizing antenna array processing. The receiver can distinguish the direction of signal arrival using the MUSIC algorithm, and applying beamforming techniques can improve navigation precision. The receiver is constructed with HackRF SDRs, synchronized in time and frequency. In this work constructed GNSS receiver was studied. It was shown that it is possible to synchronize HackRF SDRs, which allows to apply MUSIC and beamforming algorithms. The receiver was studied in different environments: open field, low reflection and urbanistic environment with tall buildings. It was shown that signal to noise ratio is improved up to 8 dB by applying beamforming. Also, it was revealed that by using MUSIC, it is possible to detect the angle of arrival of GNSS signals and also, it is possible to see reflected signals; when array processing was applied, deviation of receiver coordinates was improved. |
