Look-ahead scheduling for energy-efficiency and low-latency in wireless sensor networks

Abstract

The operation of a sensor node is limited by the initially equipped battery which is hard to be recharged or replaced. Thus reducing unnecessary energy consumption is one of the most important requirements. Most energy waste is from the always-on wireless interface and many new MAC protocols have been suggested to solve the problem. However, they sacrifice the MAC latency, especially, with multi-hop forwarding.In our approach, we designed a novel MAC protocol which has both low latency and power efficiency by separating channel reservation process and data transmission process. The sensor nodes having data to forward are efficiently scheduled during reservation process. The other nodes with no schedule go to sleep to save energy and only scheduled nodes are awake during scheduled time and transmit data. The performance of our protocol is evaluated through simulations.

TreeDMA: a hybrid MAC/routing solution for small-scale wireless networks

“…Overhearing has been utilized in ad hoc networking as a way of reducing extra transmissions. In [12], Kim includes a reservation period in which overhearing of RTS and data packets were used in lieu of CTS and ACK packets. ISO-MAC [13] includes extra fields in the packet header for slot availability information.…”

An Adaptive Energy-Efficient and Low-Latency MAC Protocol in Wireless Sensor Networks

“…The disadvantage of LAS-MAC [3] is that the nodes having data to forward must wait for next duty circle when they overhear interference, but the channel may not always be busy in this duty circle. So the throughput is reduced.…”

FlexiTP: A Flexible-Schedule-Based TDMA Protocol for Fault-Tolerant and Energy-Efficient Wireless Sensor Networks

“…It is desirable to prolong the lifetime of a network by minimizing energy consumption in sensor network operations. Furthermore, the users of sensor networks need end-to-end guarantees on data delivery [3], [4]: predictable throughput for gathered data, fair access to the network for all data-gathering nodes, and robust self-healing of the network when nodes join or leave the network and when communication conditions change [5], [6], [7]. In practice, however, it has proved difficult to achieve these guarantees, because of the severe resource constraints (battery power and data memory) of sensor network nodes and the hostile environments in which they must operate [8].…”