Distributed source-user estimation over directed graphs

This paper tackles an estimation problem in networked systems. A given time-varying signal is assumed to be measured or computed by only a subset of agents, named sources, while the other agents, the users, are required to estimate this signal in a distributed way. Each agent communicates only with a subset of neighbouring mates and the communication topology is described by a directed graph with relatively weak connectivity properties. The problem is solved for two class of signals with, respectively, null or bounded derivative of a given order, by resorting to a bank of distributed estimators of the signal and its derivatives run by each user agent. Convergence properties and noise rejection capabilities are investigated. Simulations are run to show the effectiveness of the approach and assess its performance.