Blocking analysis of persistent resource allocations for M2M applications in wireless systems

Wide area wireless systems conventionally employ dynamic scheduling for stochastic or bursty applications and persistent resource allocations of a given period for deterministic applications such as voice. When considering persistent resource allocations for machine-to-machine (M2M) applications from different markets, a wide range of allocation periods may be required to fully support the diversity of applications. The set of periods supported by the wireless system is a compromise between efficient use of the available resources and supporting as many M2M applications as possible. We consider two schemes: a simply periodic system which offers a limited set of periods with very efficient use of resources, and a complex periodic system which offers a wider range of periods at the cost of lower efficiency. We derive formulae for the blocking probability of these two systems by considering different resource sharing policies of the Erlang Multirate Loss Model (EMLM) and the concepts of packing (when a new persistent allocation is admitted to the system) and repacking (when an existing persistent allocation leaves the system). The theoretical models are verified using a discrete event simulation with variable offered traffic loads. The concepts discussed in this paper are generic, but may find particular application in Long Term Evolution (LTE) and Worldwide Interoperability for Microwave Access (WiMAX) networks for the purposes of system configuration (particularly in terms of the set of periods supported for persistent allocations), resource dimensioning and system performance characterisation.