Cross-Layer Network Lifetime Maximization for Hybrid Sensor Networks

Home energy management systems (HEMSs) are considered as an important part of the realization of smart grids. Wireless sensor networks (WSNs) and power line communication (PLC) are two technology enablers for the HEMSs. However, the lifetime of WSNs is limited by the battery capacity while PLC lacks the flexibility that WSNs offer. We propose a hybrid sensor network, which consists of both wireless sensor nodes and power line sensor nodes to prolong the network lifetime. The network lifetime maximization problem is formulated by considering the physical, medium access control (MAC) and routing layers jointly. We derive a closed-form expression of the globally optimal solution for network lifetime maximization. Numerical results show that the network lifetime is prolonged significantly in the presence of a small number of power line sensors, compared to a pure WSN with the same total number of sensors.