A Multi-channel Timeslot Scheduling Algorithm for Link Recovery in Wireless Multi-hop Sensor Networks

In this paper, we propose a TDMA scheduling algorithm to provide on-time packet delivery in wireless multi hop sensor networks. In multi-hop environments, scheduling of timeslot is optimized on end-to-end basis. However, the end-to end transmission is unavailable if a scheduled link on the communication path is failed by wireless interferences and/or device functional errors. We exploit substitute communication paths to avoid the link failures. Our proposed algorithm schedules communication links on the substitute path by using dedicated timeslots in the frame. The max-min optimization is used to maximize the number of dedicated timeslots to establish substitute paths. We evaluate the performance of our proposed algorithm using QualNet network simulator. The simulation results show that our proposed algorithm achieves higher path survival ratio while satisfying end-to-end delay bound. Especially, our algorithm recovers communication paths eleven times more than a previous work when all communication links in the network are failed.