Minimizing age of correlated information for wireless camera networks

Freshness of information is of critical importance for a variety of applications based on wireless camera networks where multi-view image processing is required. In this study, we propose to jointly optimize the use of communication and computing resources such that information from multiple views is delivered is obtained in a timely fashion. To this end, we extend the concept of age of information to capture packets carrying correlated data. We consider the joint optimization of processing node assignment and camera transmission policy, so as to minimize the maximum peak age of information from all sources. We formulate the multi-view age minimization problem (MVAM) and prove that it is NP-hard. We provide fundamental results including tractable cases and optimality conditions. To solve the MVAM efficiently, we develop a modular optimization algorithm following a decomposition approach. Numerical results show that, by employing our approach, the maximum peak age is significantly reduced in comparison to a traditional centralized solution with minimum-time scheduling.