# Analysis of the Impact of Multipath on Galileo System Measurements
## 1 Introduction
Over the past several years, multipath error analysis has been performed for Multi-GNSS solutions (GPS, GLONASS, Galileo, and BeiDou) [21] as well as single-system solutions: BeiDou (e.g., [22; 23]) and Galileo (e.g., [24; 25; 26]). The analysis demonstrates the superiority of the Galileo code observations, especially the E5 AltBOC signal, over GPS observations as well as BeiDou and GLONASS systems (RMS of code multipath and noises for E5 Galileo equal to 0.1 cm, whereas for signals of other GNSS systems, the value of this error ranges from 0.2 to 0.4 m). The largest multipath errors were recorded for GLONASS observations. The Galileo system was designed with improved features compared to the GPS system. One of the improvements consists of a greater accuracy of code observations, especially in terms of the resistance to the multipath effect. The appropriate selection of the structure of the navigation signal can effectively increase the efficiency of a given signal type under conditions of increased multipath impact as well as measurement noise. Through the use of novel modulation techniques, the signal adopts certain characteristics that make measurement processing in the receiver more resistant to various types of disturbances, including those related to the multipath effect [27]. The main objective of this paper is to determine the multipath impact on Galileo measurements and to compare the results to GPS measurements. The analyses of the multipath effect were determined based on code observations, carrier-phase observations, and positioning results. The main objective of the experiment was the determination of multipath errors for observations in the statistical domain, taking into account measurement noise and its time correlation. Positioning results as well as observations were analyzed by also using the wavelet transform. Code multipath error was determined using CMC combination, and phase multipath error was determined using the measurements for a very short baseline. In this paper, a comparative analysis of the impact of multipath on Galileo and GPS measurements is presented in a comprehensive way, using all available signals of both systems. The provided research allows us to verify whether the Galileo system does indeed offer improvements in terms of its resistance to the multipath effect compared to the GPS system. The comparison of the results for the Galileo system to GPS was dictated by the fact that almost all multi-system solutions use the latter. Additionally, it is also an operational system that has been in use for the longest period of time and has been the subject of extensive research on GNSS. The paper is organized as follows. Section 2 presents the Galileo system, especially in terms of the increased resistance of the observations to the multipath effect. Section 3 describes the methodology used for the determination of the multipath impact, which were adopted in this paper. Section 4 is devoted to the analysis of the multipath effect on code observations, carrier-phase observations, and estimated receiver positions. Section 5 contains a discussion and the most important results. Finally, in Section 6, the conclusions and possible future work are presented.