# Investigation of Static and Kinematic Surveying Performance of Handheld GNSS Receiver +
## 3 Performance Analysis Results and Discussions  
### Static Scenario  
Static data collected with the Garmin receiver was first processed using the relative positioning method. During the process, three GNSS reference stations located at different distances from the Garmin receiver were used to reveal the effect of baseline length on static positioning accuracy. One of the International GNSS Service (IGS) stations, ISTA, and two of the continuously operating reference stations, PALA and YALI, were used as reference control stations to form a very short, short and relatively long baselines of about 45 m, 5.1 km, and 73.2 km, respectively. In addition, the collected daily dataset was also divided into shorter sessions of 1, 2, and 4 h to assess the performance of the receiver as a function of occupation time. All these formed baselines were processed with Topcon MAGNET Tools GNSS software v.8.1 using IGS precise orbit files. Tropospheric path delay was modeled using the VMF3 grid product. In order to investigate the effect of the satellite constellation on the accuracy performance, all baselines were processed with two different satellite constellations as GPS (G-only) and GPS&GLONASS (G&R) combination. The observations on the L1 and L5 frequencies for GPS and L1 frequency for GLONASS constellations were used. The coordinates of the handheld receiver were estimated both as fixed or float ambiguity resolutions depending on the baseline length and occupation time. The coordinates of the Garmin receiver obtained with baseline solutions were compared with the known coordinates of the point (CP-1), and the differences in 2D position  
Figure 2: (**a**) Kinematic measurement setup; (**b**) Kinematic trajectory; (**c**) Number of satellites; (**d**) PDOP values; (**e**) Signal-to-Noise (SNR) values; (**f**) Multipath values. and ellipsoidal height components for all solutions were given in Figure 3a,b. It should be noted that the differences in the order of meters were obtained in ambiguity float solutions; thus, only the results of ambiguity-fixed solutions were given here. The term \"Float Sol.\" in the graphics means that the corresponding solutions were obtained as \"ambiguity-float solution\". The others indicated that the coordinates were estimated with ambiguity-fixed solution. The same datasets were also processed with the Canadian Spatial Reference System-Precise Point Positioning (CSRS-PPP), one of the most widely used online GNSS PPP processing services. The service was launched in 2003 and estimates the accurate coordinates in PPP mode using precise satellite orbits, clock corrections, and biases. In this service, PPP coordinates are derived using the L1 and L2 frequencies of the GPS and GLONASS constellations. It is sufficient for users to send the GNSS data collected in the field in RINEX, *.zip, *.gz, *.z, *.tar, *.yyo formats via the user-friendly website of the service. CSRS-PPP produces ITRF solutions in the IGS20 reference frame, starting with GNSS measurements logged on Sunday, 27 November 2022. The most recent information on this service can be found in [PERSON] et al. (2020) and the CSRS-PPP website ([[https://webapp.geod.nrcan.gc.ca](https://webapp.geod.nrcan.gc.ca)]([https://webapp.geod.nrcan.gc.ca](https://webapp.geod.nrcan.gc.ca)), accessed on 20 May 2024). Shortly after sending the data to the service, combined GPS&GLONASS PPP-derived coordinates, including many outputs containing different information, graphics, and detailed solution reports, were sent to the e-mail address that we introduced at the beginning. The static PPP coordinates of the Garmin receiver were compared with the known coordinates, and the differences were given in Figure 4 as 2D position and height for the G&R combined solution at different occupation times. It should be noted that although the Garmin receiver dataset contains L1 and L5 frequencies, only the L1 frequency is used in the solution. Accordingly, the PPP coordinates are calculated with a single-frequency solution.