# Experimental Evaluation of a LoRa Wildlife Monitoring Network in a Forest Vegetation Area
## 4 Testbed and Experimental Setup  
The experimental testbed deployment consists of a virtual fence of poles, where each pole is a full, autonomous, networked system. So far, the testbed consists of poles placed at different locations and deployed in the San Rossore Park in Pisa, Italy, which leverages the state-of-the-art LoRaWAN network technology. Focusing on the network performance of LoRa technology, we make use of the EU version of the RN2483 LoRa module, which operates in the 433 MHz and 868 MHz bands. Monitoring data are transmitted from the prototype devices to the LoRa gateway in a periodic manner. We make use of a gateway embedded with LoRa capabilities that works in the 433 MHz and 868 MHz frequencies' bands and placed at a height of 3 m, developed for outdoor use. The LoRa gateway is made up of the following hardware: a RAK831 LoRaWAN gateway, which operates in the 433 MHz and 868 MHz band. Such a gateway embeds a Semtech SX1301 LoRaWAN transceiver. The gateway is also equipped with a 4.15 dBi antenna for experimental measurements, performed both in the 433 MHz and 868 MHz frequency bands. The prototypes are placed at a height of 1.7 m above the ground. The LoRa gateway device is placed at a fixed position during all the measurements, while the prototypes are deployed at different locations in the forest vegetation area, with the aim of covering different types of environments. The link measurements at each location are carried out sequentially with each prototype device and the LoRa gateway being configured with identical transmission parameters and cycling through various combination of different SF values \((7,8,9,10,11,12)\) with varying CR value alternating  
Figure 5: LoRa Field Packet Generator. Figure 6: RN2483 Block Diagram. between 4/5 and 4/8, and a constant value of 125 KHz for the bandwidth (BW) parameter. In this paper, the deployment focuses on LoRaWAN class A devices. The packet payload length is varied between 17 bytes, 37 bytes and 43 bytes. With respect to the LoRa RN2483 end node, we set the transmission power to 9.9 dBm and 10.4 dBm for the 433 MHz and 868 MHz bands, respectively. This transmitted power in the 433 MHz was set in order not to exceed the max EIRP for the 433 MHz frequency band, since we are utilizing an antenna whose gain is 2.15 dBi. The power used in the 868 MHz band was chosen consequently to guarantee the same system gain and have results comparable between the two bands. Table 3 briefly presents the RF specifications of the system used. To plan the deployment, it is important to obtain some intuitions about the communication range of the different types of devices through some tests. Figure 7 illustrates the topographical area of the San Rossore Park. Superimposed on Google Earth Pro are the devices and the gateway. The terrains in these locations are relatively flat and the vegetations consists mainly of oak and pine trees. The oak and pine trees are about 10 m and 20 m high, respectively. The map in Figure 7 shows the position of the gateway and the two sets of positions (distinguished by color) where transmissions were made. Figure 8 presents an example of the position in the green subset, where the view of the sky is almost obscured by the pine tree canopies, while Figure 8 shows the position of the red set where vegetation ends at about 20 m from the transmitter, reproducing the installation in the protection of a cultivated field. Table 4 shows the approximate straight line distance of the different endpoints from the gateway. The experiments performed were conducted during sunny and cloudy days with an average temperature of 25 \({}^{\circ}\)C and relative humidity in the 60-67% interval. In the short-term static scenario, for each configuration, 10 experiment runs are performed. Each experiment run consists in the transmission of a sequence of 300 packets.