# Experimental Study on LTE Mobile Network Performance Parameters for Controlled Drone Flights
## 5 Evaluation and Analysis of Measured Results
### Sinr  
SINR is the ratio between signal power and the power of noise and interference. Just like RSRQ, it is a measurement of signal quality, but unlike RSRQ, which only considers the strength of the signal, it also shows the strength of noise. The threshold of SINR was set to \(-5\) dB and anything below would be considered as poor performance. In the assessment of SINR, the categories were set at \(-2.5\) to \(-5\) dB, \(-5\) to \(-7.5\) dB, and \(-7.5\) to \(-10\) dB. This proved to be a challenge as in a regular network configuration the value of SINR will rarely drop below \(-5\) dB as it is very likely that the UE will have connected to a different base station before this drop in SINR occurs. The results are visible below in Table 7. Percentages of values above the threshold are market in range: 95-100% (dark green); 94-85% (green); 84-75% (beige); \(<\)74% (pinkish).  
As visible, network parameters when SINR is below \(-5\) dB can be unpredictable. For this reason, it seems that a threshold of \(-5\) dB is sufficient to provide a reliable network. Conjunction between SINR and RSRP in the range of \(-5\) to \(-7.5\) dB is shown in Figure 11.  
\begin{table}
\begin{tabular}{c c c c c c c c c c c c c c c c c c c c} \hline \hline \multicolumn{2}{c}{**SINR**} & \multicolumn{2}{c}{**RSRP, \%**} & \multicolumn{2}{c}{**RSRQ, \%**} & \multicolumn{2}{c}{**Downlink, \%**} & \multicolumn{2}{c}{**Uplink, \%**} & \multicolumn{2}{c}{**Ping. \%**} \\ \multicolumn{2}{c}{**Range, dB**} & \multicolumn{2}{c}{**40**} & \multicolumn{2}{c}{**60**} & \multicolumn{2}{c}{**90**} & \multicolumn{2}{c}{**110**} & \multicolumn{2}{c}{**40**} & \multicolumn{2}{c}{**60**} & \multicolumn{2}{c}{**90**} & \multicolumn{2}{c}{**110**} & \multicolumn{2}{c}{**40**} & \multicolumn{2}{c}{**60**} & \multicolumn{2}{c}{**90**} & \multicolumn{2}{c}{**110**} & \multicolumn{2}{c}{**40**} & \multicolumn{2}{c}{**60**} & \multicolumn{2}{c}{**90**} & \multicolumn{2}{c}{**110**} \\ \hline \((-2.5-5)\) & 67 & 89 & 82 & 89 & 39 & 40 & 23 & 23 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 \\ \((-5.7-5)\) & 29 & 53 & 55 & 83 & 9 & 7 & 2 & 5 & 72 & 100 & 53 & 80 & 100 & 100 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 \\ \((-7.5-10)\) & 7 & 30 & 59 & 31 & 7 & 0 & 0 & 0 & - & - & 10 & 100 & 100 & 100 & 100 & 100 & - & 10 & 22 & 10 \\  &As visible in Figure 11, RSRP is mostly below the threshold at lower SINR except for 110 m height. SINR in conjunction with RSRQ is visible in Figure 12.  
Figure 11: The conjunction between SINR and RSRP in SINR range (\(-5\) to \(-7.5\) dB) at (**A**) 40 m, (**B**) 60 m, (**C**) 90 m, and (**D**) 110 m height.  
Figure 12: The conjunction between SINR and RSRQ in SINR range (\(-5\) to \(-7.5\) dB) at (**A**) 40 m, (**B**) 60 m, (**C**) 90 m, and (**D**) 110 m height.  
Figure 12 clearly shows that conjuring RSRQ values to lower SINR values are below the threshold and even below \(-18\) dB as previously assessed to be an acceptable RSRQ value. In Figure 13 the average value of every 50 m of SINR is visible. As shown, the SINR value will rarely fall below \(-5\) dB so the dataset available is limited.  
To summarize, it is clear that when looking at other connection parameters, when RSRQ values are below \(-16\) dB and in the region of \(-16\) to \(-18\) dB, the parameters such as RSRP, SINR, downlink, uplink, and ping meet their set KPIs with percentages similar to when RSRP is recorded at \(-14\) to \(-16\) dB. This means that if a connection has an RSRQ value above \(-18\) dB, it can be considered stable. However, when RSRP and SINR values drop below their set KPI values of \(-100\) dBm and \(-5\) dBm, these connections become unstable and unreliable as shown in the tables above. This means that their KPI values are sufficient to provide a stable connection.