Data Aggregation Scheduling with Fixed Aggregation Ratio in IoT Sensor Networks

Data aggregation is an essential technique to save energy and reduce communication delay in multi-hop wireless sensor networks. Most current studies assume that each node can aggregate data from an arbitrary number of children in a single transmission, e.g., MAX/MIN/COUNT functions performed on numeric data. This study considers a data aggregation model with a fixed aggregation ratio, where each transmission is only allowed to aggregate data from a predefined number of data units. Intermediate sensor nodes, therefore, have to forward multiple times if the total number of data units it receives exceeds the aggregation ratio. We propose a first scheduling algorithm for the problem that priorities nodes in dense area to transmit early, ensures no signal collisions when multiple sensor nodes transmit, and at the same time adheres to an aggregation ratio. Simulation results demonstrate the performance of the proposed scheduling algorithm in various system configurations.