Probabilistic polling for multi-hop energy harvesting wireless sensor networks

In this paper, we propose a medium access control protocol (EH-MAC) for multi-hop energy harvesting wireless sensor networks (EH-WSNs). In EH-WSNs, the main goal is to match energy consumption with the energy harvesting rate which is different from minimizing energy consumption in battery-operated WSNs. Unlike most existing MAC protocols that are designed to extend network lifetime, EH-MAC is designed to achieve high throughput given the varying amount of ambient energy that can be harvested from the environment at different locations and times. EH-MAC is based on asynchronous, receiver-initiated polling; however, unlike traditional random backoff mechanisms, it uses probabilistic polling to reduce data packet collisions. EH-MAC also dynamically adjusts the number of polling packets to minimize interference. Performance results show that EH-MAC increases network capacity and data throughput over other MAC protocols for EH-WSNs.