Fig. 3

Time series of network operation. This figure shows the time series of the operation of WSNs, where a shows the time series of the operation of the end-device, b shows the time series of the operation of the router, T_s is the transmission time, P_T is the transmission power, P_R is the reception power, and n is the number of child nodes of the router. Here, the end-device enters a sleep mode when no information is transmitted, while the router waits for a receivable state when no information is transmitted