## 2 Related Works  
In the literature review, many works related to the use of LoRa were found in a wide variety of services that involve the use of wireless technologies. In works such as [10; 13; 17; 18; 19; 20; 21; 22; 23; 24; 25; 26; 27; 28; 29; 30; 31; 32] the operation of LoRa technology in a variety of services is evaluated, using basic messages at the link layer, without any support at the network layer. In contrast, works such as [2; 14; 19; 28; 33] evaluated the operation of LoRa using the LoRaWAN network protocol. The LoRaWAN network protocol increases communication security and allows operational adaptability of some parameters, however it introduces some limitations regarding the use of certain frequencies (because it must be used on specific channels) and packet size [14]. Regarding the type of services evaluated with LoRa technology, some reviewed works [2; 13; 14; 21; 24; 33] are related to tracking transportation services (the type of service evaluated in this paper), however many of them [10; 17; 18; 19; 20; 22; 23; 25; 26; 27; 28; 29; 30; 31; 32] are related to other services or a specific service is not mentioned. In works such as [2; 10; 13; 17; 18; 19; 20; 21; 22; 23; 24; 25; 26; 27; 28; 29; 30; 31; 32; 33], the authors perform some experiments to evaluate LoRa performance, however in very few cases a sufficient number of tests is performed, by varying parameters such as distance, number of devices and LoRa configuration settings. In [18], [PERSON] et al. use a large number of possible settings of LoRa, with different spreading factors, bandwidth settings, coding rates and transmission powers. The authors performed a detailed experimental analysis of LoRa transmission parameter settings on energy consumption and communication reliability. In the experiments they developed, they used a sender and a receiver located in an office building, at a distance of 50 m and with some walls in between. The sender transmitted 255 packets on each transmission setting. The experiment cycles used 1152 settings, SF (from 7 to 12), BW (125 kHz, 250 kHz and 500 kHz), CR (4/5, 4/6, 4/7 and 4/8) and TP (2 dBm to 17 dBm). Although numerous settings were used in this work (many more than those used in our work), the characteristics of the experiments (in terms of number of devices, packet rate, and distance between device and gateway) are different in our context, also the work was focused on energy consumption. In [23], the authors also use a considerable number of settings, but use a simulator to test the different settings to examine and understand scalability of LoRa networks. Although a great variety of settings are used in the tests of this evaluated work, when using a simulator (instead of field tests), the results obtained could be ruling out some important aspects that affect the operation of LoRa. Additionally, the characteristics of the experiments do not conform to those of a transit vehicle tracking service. In [17] the authors used 18 settings, varying the values of the LoRa technology parameters (SF, CR, BW and bit rate). The tests used three types of scenarios: indoor, outdoor, and underground, with distances between a few meters and 165 m and a packet rate of 1 every 5 s. Although the test environment tries to emulate a timely report of a typical IoT sensor for urban monitoring, the performed experiments vary considerably in aspects such as the total number of settings, the distances and the displacement of the devices, with respect to the present paper. Works related to mobility services [2; 13; 14; 21; 24; 33] performed field tests, mostly using vehicles traveling on certain types of routes, but have important limitations in terms of the number of evaluated settings. Additionally, some works use a limited number of devices, and in some others speed variation is not considered as a factor that can affect the operation of LoRa. The authors in [24] state that LoRa can be effectively utilized for moderately dense networks of very low traffic devices not having strict latency or reliability requirements.