Distributed conjugate gradient strategies for distributed estimation over sensor networks

This paper presents distributed adaptive algorithms based on the conjugate gradient (CG) method for distributed networks. Both incremental and diffusion adaptive solutions are all considered. The distributed conventional CG (CCG) and modified CG (MCG) algorithms have an improved performance in terms of mean square error as compared with least-mean square (LMS)-based algorithms and a performance that is close to recursive least-squares (RLS) algorithms. The resulting algorithms are distributed, cooperative and able to respond in real time to changes in the environment.