# Evaluating LoRaWAN Connectivity in a Marine Scenario
## 2 Material and Methods
### Experimental Set-Up
During the tests, the LoRaWAN protocol with data rate optimization enabled was used: all the end-nodes were set up to register to the network using OTAA, and all parameters related to the LoRa transmission were available from the employed gateways were archived. Each node had a different payload size: specifically, for the three TIAMO nodes the length was 12 bytes, for the Field Test it varied from 8 to 24 bytes depending on the presence of the GPS data and if the transmission has been triggered by pressing a pushbutton or not, whereas for LT I/O Controllers and the spectrometer the payload size was fixed to 12 and 21 bytes, respectively. The evaluation of the LoRa connectivity was performed in two different scenarios: the first one in the coastal area close to the harbor of Genoa; the second one in the Northwestern Mediterranean Sea, a semi-enclosed basin with a peculiar orography, characterized by steep mountains close to the coast. These geographic constraints allow the investigation of the connectivity from the open ocean towards the coast, thus exploiting the feasibility to install gateways on the hills behind the sea in line of sight (LOS), complying with the limit imposed by the Fresnel zone. During the first test, the passenger vessel for public transport service navigating close to the coast during two crossings from Porto Antico to Pegli and back was used (Figure 2a). The end-node TIAMO 3 (Figure 2b), the Field Test, and two LT I/O Controllers (Figure 2c) were installed on the upper deck of the vessel at about 4 m above the sea level, while the spectrometer (Figure 2d) was clamped on a pole and put the outboard on the lower deck to monitor sea color from about 2 m above the sea level. Figure 2: **(a)** Map of the track of the passenger vessel travelling from Porto Antico to Pegli and of the position of the five gateways simultaneously operating on land, on hills behind the city center of Genoa. **(b)** Two TIAMO end-nodes for the acquisition of meteorological parameters, **(c)** two LT I/O Controllers, and **(d)** the spectrometer installed on the passenger vessel. All available gateways were simultaneously operating from 12:30 UTC to 15:30 UTC on land (Table 1), and the two passages from Porto Antico to Pegli and back had departure time at 13:15 UTC from Porto Antico and at 13:40 UTC from Pegli, respectively. The second test was performed during the research cruise ICOS20 from 19 October up to 21 October 2020 with the R/V Dallaporta operated by the National Research Council of Italy. The research cruise started and ended in La Spezia, and, during the three days of navigation, the route depended on the need for performing standard oceanographic measurements (i.e., Conductivity Temperature Depth (CTD) casts and water sampling with the on-board rosette) in the basin and around the W1M3A observatory [33; 34; 35], one of the oldest infrastructures of the National Research Council of Italy, part of ERIC EMSO and of the marine component of ERIC ICOS (Figure 3). The end-node TIAMO 3 and one LT I/O Controller were installed on the bow of the R/V Dallaporta during the entire navigation. The Field Test end-node was positioned on the bow of the vessel during the navigation except during the late afternoon of 19 October 2020, when it was temporarily installed on the W1M3A observatory during the inspection to the platform. On the vessel, the gateway LG308 3 was installed close to the nodes during the navigation, but it forwarded LoRaWAN packets to the server only under GSM coverage. Three gateways operated on the coast on the evening of 19 October and on the morning of 20 October 2020 to test the connectivity from the open ocean to the coast: two LG308 gateways were installed on the hills behind Genoa, whereas another wireless gateway operated by ISILINE s.r.l. on Mount Moro was fully operational during the tests. One gateway (LG308 1) changed its position during the two days. Table 2 summarizes the location of the three gateways during the two days of testing.