Implementation of LPWAN over white spaces for practical deployment

Abstract

Low-Power Wide-Area Network (LPWAN) is an enabling Internet-of-Things (IoT) technology that supports long-range, low-power, and low-cost connectivity to numerous devices. To avoid the crowd in the limited ISM band (where most LPWANs operate) and the cost of licensed band, the recently proposed SNOW (Sensor Network over White Spaces) is a promising LPWAN platform that operates over the TV white spaces. Nevertheless, the current SNOW implementation uses USRP devices as LPWAN nodes which have high cost a $750 USD per device) and large form-factor, hindering the applicability of this technology in practical deployment. In this paper, we implement SNOW using low-cost, low form-factor, low-power, and widely available commercial off-the-shelf (COTS) devices to enable its practical and large-scale deployment. Our choice of the COTS device (TI CC1310) consequently brings down the cost and the form-factor of a SNOW node by 25x and 10x, respectively. Such implementation of SNOW on CC1310 devices faces a number of challenges to enable link reliability and communication range. Our implementation addresses these challenges by handling peak-to-average power ratio problem, channel estimation, carrier frequency offset, and near-far power problem. Our deployment in the city of Detroit, Michigan demonstrates that CC1310-based SNOW can achieve uplink and downlink throughputs of 11.2kbps and 4.8kbps per node, respectively, over a distance of 1km. Also, the overall throughput in the uplink increases linearly with the increase in the number of SNOW nodes.