Calculation of link budget from LoRa ground sensor to IoTs satellite

LoRa is a Low-Power Wide-Area Network (LPWAN) technology for Internet of Things (IoTs) application. Its advantages are low power consumption, inexpensive equipment cost, highly- secure access, and most importantly, good for long-range communication. Currently, LoRa network are extensively deployed worldwide. In the near future, that LoRa gateway may not be able to provide sufficient coverage for the ever-increasing deployment. A solution is to move the LoRa gateway up high to the satellite. The objective of this study was to theoretically investigate the feasibility of successful communication between ground sensor and LoRa gateway mounted in a satellite. In this study, sets of transmission parameters were analyzed whether, in principles, they would be able to support such kind of communication setup. For example, LoRa communicated in the frequency band 923 – 925 MHz in Thailand. Modified mathematical expressions were derived for link budget calculation. Using certain assumptions and this mathematical model, we discovered that, in principles, a suitable set of transmission parameters would be able to make the link budget sufficiently high so that this communication scheme would be feasible. The findings from this study may directly benefit developers of new applications of LoRa and IoTs satellite in their effort to design a communication scheme for their system. Nevertheless, the discovered feasibility was from the standpoints of theoretical matters. A valid experiment is needed in a future research to actually confirm this feasibility.