Wireless Sensor Networks and the Internet of Things: Optimal Estimation With Nonuniform Quantization and Bandwidth Allocation

Wireless sensor networks (WSNs) are an invaluable resource for realizing the vision of the Internet of Things. This paper investigates the energy minimization problem for the joint estimation of a noise-corrupted parameter in WSNs, where the sensors send digital signals to a fusion center via orthogonal channels. In particular, each sensor chooses a quantization level, a modulation order, and a transmission bandwidth for its link to the fusion center with the goal to minimize the total energy consumption at the sensors. It is shown that this problem can be approximated as a convex optimization problem and an efficient iterative algorithm is proposed to compute the near-optimal solution. Simulation results are provided to validate the analysis.