  In a communication setting where multiple sources share a single channel to
provide status updates to a remote monitor, source transmissions need to be
scheduled appropriately to maintain timely communication between each of the
sources and the monitor. We consider age-agnostic scheduling policies which are
advantageous due to their simplicity of implementation. Further, we focus on a
special class of age-agnostic policies, called cyclic schedulers, where each
source is scheduled based on a fixed cyclic pattern. We use weighted average
age of information (AoI) to quantify the timeliness of communication. We
develop a Markov chain formulation to compute the exact mean AoI for the case
of two-source cyclic schedulers. Based on the obtained age expression, we
develop an algorithm that generates near-optimal cyclic schedulers to minimize
the weighted average AoI for two heterogeneous sources, in the presence of
channel errors.
