Duty Cycle Criterion for Target Packet Delay of S-MAC Protocol

Generally, in sensor-medium access control (S-MAC) protocol, lower duty cycle (DC) causes longer packet delay, although it gives more efficient energy consumption. Moreover, under the environments of burst packet generation, the increase of packet delay by node contention will also induce serious performance degradation. Therefore, we find the criterion of the DC value to satisfy a target packet delay of the S-MAC protocol with contention-based access mechanism. For this, the packet delay of the S-MAC protocol in single-hop is first analyzed by reflecting the S-MAC architecture with a constant cycle under saturated condition, and then we provide the DC criterion for the target packet delay. Finally, numerical results show the DC criterion and its corresponding life time of a practical sensor mote running the S-MAC, when the target packet delay is given