Downlink Power Budget and Bit Error Analysis for LoRa-Based Sensor Node-to-Satellite Link in the Industrial, Scientific, and Medical Frequency Bands

In this paper, the downlink power budget and bit error analysis for LoRa-based sensor node-to-satellite link in the industrial, scientific, and medical (ISM) frequency bands is presented. The study evaluated the path loss, rain attenuation, operating carrier to noise ratio (C/N), link margin, bit error probability (BER), and the feasibility of wireless communication for the downlink of five selected frequencies (0.45492 GHz, 0.9233 GHz, 2.433 GHz, 5.821 GHz, and 24.021 GHz) in the ISM frequency bands. The EGS (AJISAI) geodetic satellite with NORAD ID of 16,908 and orbital height of 1480.33 km was used for the case study with the earth station sensor node located at Akwa Ibom State Universality main campus at Mkpat Enin with longitude of 7.761340 and latitude of 4.625907. The satellite link has a slant range of 3374.8 km, and the simulation results show the free space loss increases with frequency from 156.2 dB at 0.45492 GHz to 190.6 dB at 24.021 GHz. Also, the rain attenuation, Ap, increases with frequency; for percentage (p) exceeded rain intensity of 0.01%, Ap increased from 0.00534 dB at 0.45492 GHz to 96.09238 dB at 24.021 GHz. Again, for any given value of p, the value of C/N decreases with frequency; for p = 0.01%, C/N decreased from −10.36 dB at 0.45492 GHz to −143.67 dB at 24.021 GHz. On the other hand, for any given frequency, C/N decreases with p; for f = 24.021 GHz, C/N decreased from −10.36 at p = 1.0% to −196.47 dB at p = 0.003%. Furthermore, for the frequency of 0.45492 GHz and 0.9233 GHz, the link margins are positive; hence wireless communication is feasible.