  With the rapid development of cloud and edge computing, Internet of Things
(IoT) applications have been deployed in various aspects of human life. In this
paper, we design and implement a holistic LoRa-based IoT system with LoRa
communication capabilities, named SPARC-LoRa, which consists of field sensor
nodes and a gateway connected to the Internet. SPARC-LoRa has the following
important features. First, the proposed wireless network of SPARC-LoRa is
even-driven and using off-the-shelf microcontroller and LoRa communication
modules with a customized PCB design to integrate all the hardware. This
enables SPARC-LoRa to achieve low power consumption, long range communication,
and low cost. With a new connection-based upper layer protocol design, the
scalability and communication reliability of SPARC-loRa can be achieved.
Second, an open source software including sensor nodes and servers is designed
based on Docker container with cloud storage, computing, and LTE
functionalities. In order to achieve reliable wireless communication under
extreme conditions, a relay module is designed and applied to SPARC-LoRa to
forward the data from sensor nodes to the gateway node. The system design and
implementation is completely open source and hosted on the DigitalOcean Droplet
Cloud. Hence, the proposed system enables further research and applications in
both academia and industry. The proposed system has been tested in real fields
under different and extreme environmental conditions in Salt Lake City, Utah
and the University of Nebraska-Lincoln. The experimental results validate the
features of SPARC-LoRa including low power, reliability, and cloud services
provided by SPARC-LoRa.
