Performance of Clustered Multitask Diffusion LMS Suffering from Inter-Node Communication Delays

This brief studies a clustered multitask diffusion least mean-square strategy that accounts for communication delays in the inter- and intra-cluster information exchanges. We conduct detailed performance analysis and establish convergence criteria, both in mean and mean-square senses, to investigate the effect of inter-node communication delays on the stability and estimation performance. In particular, we derive convergence conditions and closed-form expressions for transient and steady-state mean square deviation. The concepts are verified using simulation examples, which show a precise match between theoretical and experimental steady-state MSD results.