## 3 Results and Analysis
### High Multipath Single Point Static Positioning and Antenna Effect
The above test was repeated with one GPSMap 66 unit using an external geodetic antenna, namely the NovAtel 702-GG model (NovAtel Inc, Calgary, AB, Canada) at the same location as shown in Figure 8 (left). This test was done to demonstrate antenna importance in such a high multipath environment. The GPSMap 66 and P10 units do not have connectors for an external antenna. The procedure to use the external antenna in the absence of a wired connection is fully described in [3] during evaluation of the Huawei Mate 9. The 702-GG was connected to a metallic box with its open-ended wire re-transmitting inside where the unit under test locked on the 702-GG signals. The inside of the box was lined with RF absorbent material to further decrease the strength of signals that may be coming directly from the outside through the box walls and slits. The hardware assembly  
Figure 6: (a) GPSMap 66 epoch-by-epoch GPS coordinate variations with respect with ITRF2014 coordinates under high multipath shown in Figure 4. (b) GPSMap 66 epoch-by-epoch Galileo coordinate variations with respect with ITRF2014 coordinates under high multipath shown in Figure 4.  
Figure 7: P10 epoch-by-epoch GPS coordinate variations with respect with ITRF2014 coordinates under high multipath shown in Figure 4 using internal antenna. is shown on the right side of Figure 3:0 The issue of the potential effect of re-radiation inside the box was analysed by [5] and no effect was detected, therefore validating the above procedure. The test was conducted over a 50-min period during which Galileo coverage was available. The C/N\({}_{0}\) values and code-based epoch-by-epoch single point positions are shown in Figure 3:1 The C/N\({}_{0}\) fluctuations are much smaller than when using the internal antenna due to the better multipath rejection capability of the geodetic antenna. This leads to a higher average gain of 2 dB-Hz with respect to the use of the internal antenna. The temporal coordinate variations are much smaller and demonstrate antenna importance under high multipath conditions. The GPSMap 66 latitude, longitude and height RMS values are now 1.6, 0.9 and 3.8 m for GPS and 2.2, 1.1 and 4.0 m for Galileo, which is two to three times better than the results shown in Figure 6 when using the unit's internal antenna and only slightly higher than those of the Trimble R10 L1 code epoch-by-epoch values of 0.8, 0.6 and 2.0 m shown in Figure 10 at the same location, which is remarkable. In single point positioning mode, the effect of satellite orbit and clock errors, in addition to those of the atmosphere, limits accuracy achievable, regardless of the receiver used. The use of carrier phase in differential mode leads to different levels of performance between the receivers used as will be demonstrated in the sequel with tests in differential mode. P10 position coordinate results in the same high multipath environment with the external antenna are shown in Figure 3:2 Performance remains substantially poorer than that of the GPSMap 66 shown in Figure 9 but is still better than that shown in Figure 7 for the P10 without the benefit of an external antenna. Figure 3:3 Trimble R10 epoch-by-epoch L1 C/A code coordinate variations in high multipath environment shown in Figure 3:4  
Figure 3:5 GPSMap 66 C/N\({}_{0}\) variations and epoch-by-epoch GPS and Galileo coordinate variations using external geodetic antenna.