Evaluation of Sub-Ghz Frequencies for IoT Applications

Internet of Things (IoT) is an integrated technology in which billions of devices are capacitated with digital intelligence to interconnect and communicate through the Internet, for the fulfillment of various needs obviating human intervention. Communication technologies play a vital role in the design of IoT networks, in both indoor and outdoor applications. This work presents an in-depth study on the application of the sub-GHz frequencies (915 MHz and 868 MHz) over the widely used 2.4 GHz channel, for the design of low-cost IoT networks for indoor mission-critical applications. These frequency bands were experimentally evaluated, under varying indoor environments. In addition, a mathematical model for the computation of path loss exponent, in an indoor scenario affected by random interference by movements of humans as the environmental condition, is also proposed in this paper.