Failover scenario on power shutdown of Wireless Sensor Network node

The wireless sensor network (WSN) includes many nodes which collect data from the sensors and deliver it to other location via a set of routers and gateways. A node typically consists of one or more sensor, a processor, a wireless transceiver, and a power supply unit. Failure of each component can interrupt a node function. Various hardware and software design techniques are adopted to guarantee node reliability and availability. This paper exclusively discusses hardware design to increase the availability of a node by using the failover scenario when power loss occurred. The node architecture is modified using additional second processors and uses one shared RF transceiver. The second processor, as a backup of the first processor, wakes up only when the first processor off or fails due to power loss or needs maintenance. Experiment using two Arduino Uno and ESP8266 shows that wake up time of the second processor is 1.9s on average. This architecture can maintain the uptime of a node and increase its availability.