A Distributed Scheduling Algorithm for IEEE 802.15.4e Networks

In a Wireless Sensor Network, the medium access control (MAC) layer protocol design is very important due to the constraint of the limited processing capability and the power on wireless sensors. Recently, the IEEE released a revised version of the IEEE 802.15.4, referred to as IEEE 802.15.4e, which defined the Slotted Channel Hopping (TSCH) mechanism. The TSCH then adopted the slotframe structure. A slotframe is composed of several time slots, with the time slot scheduling then planned based on the routing topology. Each sensor node knows the time when the data transmission/reception will happen from the schedule. Another feature in the IEEE 802.15.4e standard is the frequency hopping which could improve the reliability of the data transmission. However, the IEEE 802.15.4e TSCH standard does not specify how to plan the time slot scheduling. This paper will propose a distributed scheduling strategy such that each sensor node knows the time to transmit packets in a distributed and simple manner. Our simulation results demonstrate that the proposed approach is able to achieve high throughput, low latency, low control overhead, and low power consumption.