No abstract

Energy is the most important resource in wireless sensor networks. The wireless interface of sensor node consumes most of the energy and therefore many MAC protocols are adopting the periodic listen-and-sleep scheme. However, the periodic listen-and-sleep approach results in high latency and low throughput. For low latency in multi-hop forwarding without sacrificing energy efficiency, we designed a look-ahead scheduling MAC (LAS-MAC) protocol, which also works on the periodic listen-and-sleep scheme, but it reserves multi-hop packet forwarding schedules across multi-hop nodes during the listen period and forwards data packets by awaking the nodes with the reserved schedules during the sleep period. For high throughput of LAS-MAC, in addition, we add the throughput enhancement mechanism which clones the current multi-hop forwarding schedules for the subsequent data packet forwarding. Our experimental results on the MICA2 platform show that LAS-MAC achieves lower latency, higher throughput, and higher energy efficiency than 802.11-like MAC without sleeping.