Influence of Duty-Cycled Wake-Up Receiver Characteristics on Energy Consumption in Single-Hop Networks

In sensor network applications with low traffic intensity, idle channel listening is one of the main sources of energy waste. The use of a dedicated low-power wake-up receiver (WRx), which utilizes duty-cycled channel listening, can significantly reduce the idle listening energy cost. Extreme low-power design typically leads to performance losses, indirectly increasing energy costs. Striking the right balance is, therefore, very important when introducing WRxs. We present a system analysis and heuristic parameter optimization for an existing duty-cycled WRx medium access control scheme. First, we introduce a framework for analysis of energy consumption and delay of an entire single-hop network where we include WRx characteristics. The WRx characteristics are condensed into two parameters: reduction in power consumption and associated loss of performance, compared with the main receiver. The analysis framework is used to find optimal wake-up beacon and protocol parameters for different WRx characteristics to minimize the total network energy consumption per data packet. The importance of the optimization is that it provides information on if, and how much, we can save in terms of energy by introducing a WRx with a certain characteristic. We also present accurate approximations of both optimal energy savings and resulting delays.