Effect of Relay-based Communication on Probability of Detection for Spectrum Sensing in LoRaWAN

The internet of things (IoT) may be considered as an emerging paradigm that has led to the transformation of the physical world into an advanced system comprising interconnected devices on an unparalleled scale. To accommodate the spectrum, need of these numerous IoT devices concept of cognitive radio technology may be considered a boon. The cognitive radio (CR) aims to alleviate the spectrum crunch problem through detection of the available spectrum holes and their efficient utilization. This paper incorporates the spectrum sensing concept in the LoRaWAN network for better utilization of the spectrum. A non-relay and relay-based type of communication has been investigated to analyze the enhancement in the detection probability of the sensing technique for a LoRaWAN network in terms of minimal sensing time, maximum coverage, and low signal-to-noise (SNR). The effect of sensing time, distance and SNR on detection probability for 915 MHz and 866.4 MHz LoRa bands has been analyzed and critically evaluated at uplink bandwidth of 125 kHz and 250 kHz respectively using MATLAB. The simulated results validate the performance improvement through multiple relays in a LoRaWAN communication model in context to a higher probability of detection for energy detection-based spectrum sensing.