Abstract
EcoMAC is a lightweight yet powerful medium access control (MAC) protocol for Eco, an ultra-compact, highly resource-constrained wireless sensor platform. EcoMAC enables Econodes to appear logically as ZigBee end devices in infrastructure mode in a ZigBee network while supportng fast hand-off among base stations. Our protocol is collision-free without costly synchronization, thanks to pulling style communication. Another novel feature is theLink Quality Measurement (LQM), which enables handoff decision without the use of receive signal strength indicator (RSSI). Experimental results show not only fast handoff between base stations but also high scalability. EcoMAC makes possible a heterogeneous wireless sensor network that combines the powerful topology of complex, full-ZigBee systems with the convenience of compact, lightweight Eco, all with minimal added complexity.