## Materials and Methods  
### Experiment: Datasets and Location  
To evaluate the performance of the adopted PPP approach, two static tests are carried out, consisting of a dataset collected by a permanent station, located at Palermo University (Test A) and a dataset collected by a geodetic receiver placed nearby the station (Test B). The geographical positions of the tests are shown in Figure 1.  
Up to 2008, in Sicily there was not a local GNSS network; thus, the University of Palermo has designed and realized the first local level-based network in the central-western part of the island. The management of the GNSS Continuously Operating Reference Station (CORS) network, consisting of 8 stations used for technical and scientific purposes, was preliminary entrusted to the University (until 2013); later, the stations were included in the Netgeo GNSS network, managed by Topcon Italy, due to the scientific collaboration between the latter and the University of Palermo, aimed to realize the first local level based network in Sicily [28]. Furthermore, two additional permanent stations are located at Palermo University: one is equipped with a Trimble NetR9 receiver and Zephyr GNSS Geodetic II antenna (belonging to Trimble RTX network) and another station of the network is managed by Hexagon Geosystems, Italian Positioning Service (ItalPoS) (HxGN SmartNet 2020), with a LEICA GMX902 GG receiver and LEIAS10 NONE antenna. The CORS network set up in the western part of Sicily has been tested and data are used for several scientific works focused on: use of Mobile Mapping System (MMS) for integrated survey [29; 30], GNSS techniques for land and structure as dams monitoring [31; 32; 33], geological analyses [34], integrated survey in archaeological context [35; 36], and recently also geodynamic research [37]. Test A is performed collecting data by the permanent station Trimble NetR9 located at Palermo University and considering a time interval of 31 days, starting 1 July 2018-DOY (Day of Year) 182 to 31 July 2018-DOY 212. Figure 1: (**a**) Geographical position of the study area; (**b**) digital orthophoto from Italian National Geoportal, scale 1:4000, reference system UTM-WGS8433N (ETRF2000); position of Trimble permanent station and Topcon HiPer HR on a concrete pillar. The considered station is equipped with the antenna TRM55971.00 TZGD (Zephyr GNSS Geodetic II) able to acquire GPS, Galileo, GLONASS, and Beidou signals. The antenna is robust and recommended for GNSS geodetic survey. The quality and precision features characterizing the antenna are the repeatability of the sub-millimeter phase center, the robust satellite tracking at low altitude, and the reduced multipath effect. The permanent station records satellite data continuously, returning daily observation and navigation files. In particular, daily data are considered, in both RINEX hatanaka 2.11 formats, consisting of the observation files (O) and the GPS (.N), GLONASS (.G), and Galileo (.L) ephemeris files, and RINEX hatanaka 3.00 formats, consisting of the observation files (.O) and a single ephemeris file containing all the constellations analyzed (.P). Test B is carried out using a geodetic receiver and collecting data for 10 days, starting from 18 th (DOY 199) to 31 st of July 2018 (DOY 212), with an acquisition session of six hours a day. The used receiver is the Topcon HiPer HR, installed daily on a pillar placed on rooftop of Palermo University. The receiver is capable of acquiring signals from GPS, GLONASS, Galileo, BeiDou, QZSS, SBAS, and L-Band in 452 channels and using Universal Tracking Channel technology. Using the described receiver, a single file is obtained in \"*.tps\" format. In post-processing, a dedicated converter tool of Topcon (TPS2 RIN) is used to convert the file \"*.tps\" in two files in RINEX 3.02 format: the observation and navigation files. In Test B, the PPP performance using a geodetic receiver with integrated antenna are evaluated.