Optimal Scheduling for Wireless Links Under Per-User Maximum Delay QoS Constraints

A solution to the problem of finding a minimum energy packet scheduling and rate control scheme with per- packet maximum delay constraints is presented. This problem occurs naturally when QoS constraints are present in systems that support heterogeneous traffic types. The solution is shown to have the form of piecewise waterfilling between active arrival and delay constraints. A novel geometric interpretation is given, and shown to lead to an efficient iterative offline rate calculation algorithm that has a physical analogy of pulling a string through a set of pegs.