Search

In this paper, we present a MAC protocol called Hop Extended Pipelined Routing MAC (HE-PRMAC) that enables a node to send a data packet for multiple hops in a single duty cycle similar to PR-MAC and has the ability to handle traffic overhead in an efficient way. HE-PRMAC addresses delivery latency and throughput degradation in wireless sensor networks (WSNs) using hop extended mechanism and a new message, i.e., RTR message. The main goal of this research is to reduce the overhead and latency compared to R-MAC and PR-MAC. We evaluate the performance of our protocol using ns-2 simulations. As compared to R-MAC and PR-MAC, HE-PRMAC shows 22.1% less power consumption and 13.6% less packet latency on average for 250 nodes in chain, cross, and real scenario.

The problem of idle listening is one of the most significant sources of energy consumption in wireless sensor nodes. Many techniques have been proposed based on duty cycling to reduce this idle listening. This paper presents Adaptive Scheduling Predictive-Wakeup MAC (AS-PW-MAC), a new MAC protocol based on asynchronous duty cycling. AS-PW-MAC introduces RTE and RAS messages for pending data transmission. RTE and RAS are beneficial for varying traffic loads. We evaluate the performance of AS-PW-MAC through detailed ns-2 simulation and compare it to RI-MAC and PW-MAC, two well-known MAC protocols. Our evaluation includes clique, grid and random network scenarios. In all experiments, AS-PW-MAC significantly out performs RI-MAC and PW-MAC protocols. AS-PW-MAC achieves higher packet delivery ratio under a wide range of traffic loads compared to RI-MAC and PW-MAC. Especially, when there are contending flows, such as bursty traffic or transmissions from hidden nodes, AS-PW-MAC significantly improves the packet delivery ratio and delivery latency. The delivery latency for AS-PW-MAC is less than 21% compared to RI-MAC and PW-MAC. In all experiments, AS-PW-MAC maintained approximately 100% packet delivery ratio.