Low Power and Low Latency MAC Protocol: Dynamic Control of Radio Duty Cycle

In low-power and lossy networks (LLNs), power-constrained devices consume most of power to communicate with their neighbors. To save power, traditional MAC protocols usually turn off RF transceivers while there is no radio communication. Since RF transceivers consume most of their energy in idle listening, turning RF transceivers off can save significant amount of energy. However, delay of packet transmission is increased because the receiver sleeps most of time. It can lead a significant Quality of Service (QoS) decrease in protocols such as 6LoWPAN (IPv6 over Low power Wireless Personal Area Networks) and CoAP (Constrained Application Protocols). In this paper, we propose a low power and low latency MAC protocol to reduce delay while obtaining low power consumption. Our scheme makes an RF transceiver sleep most of time to save power and wake up periodically. When either receiving or sending packets occur, the wake-up period of RF transceiver shortens. In this paper, we compare our protocol with ContikiMAC, a low-power MAC protocol, by network simulation. The results of the comparison show that the latency of our protocol is lower than ContikiMAC. Our protocol also consumes similar amount of energy compared to ContikiMAC in the simulation.