Abstract: A three-layer protocol stack in a wireless communication device and a wireless communication network are provided. The three-layer protocol stack includes a physical layer; a medium access control (MAC) layer; and a network layer. The physical layer includes one or more circuits to conduct a power consumption minimization and a waveform selection. The MAC layer is configured to perform a medium access control and a resource block reconfiguration. The network layer is configured to perform an energy efficient routing and connection maintenance. The physical layer, the MAC layer and the network layer cooperate with each other to at least reduce an energy consumption of the wireless communication device.