A new cross-layer user scheduler for delay and symbol error probability in wireless multimedia relay networks

We propose a new scheduler for the dual-hop amplify-and-forward wireless multimedia relay network (WMRN). Our scheduler is designed to account for delay and symbol error probability (SEP). We develop a cross-layer scheduling approach for the downlink to balance these system metrics. Our scheduler is based on a new metric we call the delay in packet scheduling (DPS). The user with the largest weighted signal-to-noise ratio is scheduled, where the weight is a function of the DPS.We then derive analytical expressions for the probability mass function of the DPS, and the SEP of the scheduled user in Rayleigh fading. We verify our analysis via simulations. We show the probability that a target DPS is met is 30% higher for our new scheme compared to the standard opportunistic equal weight scheduler, with negligible degradation in the SEP of the scheduled user.