# Performance Evaluation of LoRa Considering Scenario Conditions
## 4 Material and Methods
For each transmission, a different set of the LoRaWAN configuration parameters, i.e., SF, CR, and BW, was employed for both up and down links. This process was periodically repeated during the duration of the test in an infinite loop as described in [20]. This strategy permitted to test different LoRa configurations simultaneously in the different scenarios under consideration. In this procedure, even if the OBU did not receive the ACK after a packet transmission, it kept running, sending a new packet after a given time-out period. The base-station continuously listened to packets and answered with a LoRaWAN ACK to each received packet. Furthermore, the base-station was configured to only answer our OBU packets, discarding in the network server side any other possible LoRaWAN received transmissions in order to avoid extra interferences or unexpected transmissions. Note that only the LoRaWAN packets transmitted from the OBU were detected by the base-station during the tests. The equipment logs showed no transmissions from other devices. As aforementioned, the tests were carried out on three different scenarios, namely, urban, suburban, and rural, which were selected depending on their architectural configuration. In all the scenarios, the same equipment and software described above was used. The OBU was placed on the vehicle, which circulated in selected routes to perform the tests. As we were interested on \begin{table}
\begin{tabular}{c c c} \hline \hline  & **End-Device** & **Base-Station** \\ \hline Output Power & +14 dBm & +14 dBm \\ Antenna Gain & +5 dBi & +8 dBi \\ Central frequency & 868 MHz & 868 MHz \\ RX Sensitivity SF = 7 & \(-123.0\) dBm & \(-126.5\) dBm \\ RX Sensitivity SF = 8 & \(-126.0\) dBm & \(-129.0\) dBm \\ RX Sensitivity SF = 9 & \(-129.0\) dBm & \(-131.5\) dBm \\ RX Sensitivity SF = 10 & \(-132.0\) dBm & \(-134.0\) dBm \\ RX Sensitivity SF = 11 & \(-133.0\) dBm & \(-136.5\) dBm \\ RX Sensitivity SF = 12 & \(-136.0\) dBm & \(-139.5\) dBm \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Summary of the equipment configuration for a BW of 125 kHz. Figure 4: Base-station detail. (**a**) Controller; (**b**) Antenna. evaluating a realistic dynamic scenario, the vehicle speed was affected by real traffic conditions. The maximum, minimum, and average speeds, including confidence intervals (\(\alpha=0.05\)), are presented in Table 3. The routes were the same for all the studied LoRaWAN PHY layer settings, so the results can be analyzed in a comparatively way for each considered scenario. The urban one was located in the city of Murcia, Spain, while traveling through its downtown. The base-station was placed on the Faculty of Computer Sciences in the University of Murcia. The base-station placement was at the edge of the rooftop of a five-story building located in an elevated position and its antenna was pointed towards the test-area by studying its radiation pattern, the distance to the sampling area, and making use of the radiation map obtained from the theoretical coverage study. This process was done trying to optimize the overall reception gain of each experiment, so the antenna remained untouched during the duration of each test. The followed route during the test included the main downtown streets with up to three lanes and high buildings and constructions of up to 15 stories in the surroundings. In turn, the suburban scenario had less adverse conditions for the radio communications, with isolated shorter buildings of up to two stories and some vegetation areas. For this scenario, the base-station placement was at the same point as in the urban one, but the antenna was accordingly pointed to the area of study. The route traveled through industrial and residential areas, with some gentle terrain elevation changes. Finally, the rural scenario was the most favorable as it presented almost free-space conditions. The terrain in which the tests were performed was flat, with lack of large constructions and barely high-vegetation.