## 5 Coverage Analysis
In performed simulations, firstly the maximum transmission range has been calculated by changing the vehicle/machinery and GW/BS antenna heights for different environmental conditions. The simulations have been repeated for each frequency band of LoRa and NB-IoT deployments in Europe. The obtained results have been given in Figures 7-9 for urban, suburban, and rural areas, respectively. As the plots show, the transmission range increases with antenna height for vehicle/machinery and GW/BS. The simulation results clearly show that the NB-IoT has better coverage when compared to LoRa for all urban, suburban, and rural environments. In the 900 MHz band, the NB-IoT transmission range varies from 9 km to over 14 km in urban and 50-100 km in rural environments. On the other side, in the 868 MHz frequency band, the LoRa's transmission range may be expected to be approximately 6 km in dense urban sites and up to 35 km in rural areas. It is clear that the LoRa coverage increases at the 433 MHz band due to the better propagation advantage. According to that, the transmission range varies from 4 km to over 10 km in urban sites and up to 45 km in rural environments in the 433 MHz frequency band. On the contrary, in the 1800 MHz band, the NB-IoT transmission range is relatively short compared to sub-GHz frequencies. Note that all simulations have been made without considering the fade margin parameter in the case of \(m=0\) dB, which introduces the theoretical upper limits of the coverage range. \[PL_{Suburban}=PL_{Urbm}-2\times\left(\log_{10}\left(\frac{f}{28}\right)\right) ^{2}-5.4, \tag{5}\]2 Coverage analysis of LoRa and NB-IoT technologies in suburban areas. \[PL_{Suburban}=PL_{Urbm}-2\times\left(\log_{10}\left(\frac{f}{28}\right)\right) ^{2}-5.4, \tag{5}\]3 Coverage analysis of LoRa and NB-IoT technologies in urban areas. It should be highlighted that the path loss mainly depends on the terrain contour and topography, and the height of antennas in realistic propagation scenarios. Depending on the nature of the propagation environment, the multipath propagation and shadowing effects may simultaneously occur on the wireless channel. Especially the disruptive impact of shadowing causes signal attenuation, and thereby the wireless network coverage is significantly affected due to environmental obstacles. To investigate the effect of fade margin on the transmission range, computer simulations were repeated by changing the fade margin parameter from 0 to 30 dB for a fixed vehicle antenna height, \(h_{v}=2\) m. In this simulation setup, the environment was assumed as rural, and the antenna heights of LoRa GW and LTE BS were also changed from 3 m to 10 m and 20 m to 30 m, respectively. As can be seen from Figure 10, both LoRa and NB-IoT coverage ranges significantly decrease due to objects obstructing the propagation path between the transmitter and receiver. When considering the harsh channel conditions for \(m=30\) dB, the LoRa transmission range is under 10 km for the 433 MHz bands. However, NB-IoT still achieves a better transmission range of up to 15 km for 800 MHz bands. It is noteworthy that when the fade margin increases, the importance of GW/BS antenna height becomes less effective, and the coverage enhancement remains negligible. To complement the theoretical coverage analysis, the connection probability between the agricultural vehicle/machinery and GW/BS was also investigated based on the Hata path loss model in urban, suburban, and rural radio propagation environments. Connection probability measures the randomness and uncertainty of achieving successful packet transmission [54; 55; 56]. When considering the multiple vehicles located at different positions on a large-scale farm, the connection probability of an individual one can be calculated depending on its distance to a GW/BS as follows:  
\[PL_{Suburban}=PL_{Urbm}-2\times\left(\log_{10}\left(\frac{f}{28}\right)\right) ^{2}-5.4, \tag{5}\]4  
where \(PL_{max}\) is the maximum allowable path loss in Equation (2).