Sensor selection schemes in smart grid

Wireless sensor and actuator networks (WSANs) have been widely implemented in smart grid to monitor and control their environment. We consider the sensor selection schemes for parameter estimation in energy constraint WSANs. To prolong the network lifetime and optimize energy consumption, only sensors experiencing favorable conditions will participate in the estimation process. In this paper, we study two different multiple access schemes between sensors and fusion center (FC): orthogonal and coherent. We compare these two schemes and derive a reasonable lower bound of distortion. Sensor selection scheme under equal power allocation is first discussed. We propose an opportunistic sensor selection scheme by solving an relaxed sensor selection problem. The asymptotic behavior is also investigated. Sensor selection scheme under optimal power allocation is then considered. We address this problem via convex optimization techniques and derive a reminiscent of the “water-filling” solution for this scenario. The validity of the proposed sensor selection schemes is finally demonstrated by numerical simulation results.