Impact of request aggregation on machine type connection establishment in LTE-advanced

This paper presents a hierarchical cluster-based protocol for LTE connection establishment of a massive number of Machine Type User Equipments (mUEs). The protocol facilitates spatial reuse of random access channel resources. Our contributions are (i) modeling and analysis of the connection request aggregation, and a study on its influence on the connection from clusterhead to base station, and (ii) an accurate joint medium access model of a random access procedure within a finite-user cluster, considering the cross-impact and interrelation between aggregation and random access procedures. A byproduct of the joint analysis is an accurate finite-user model of random access without aggregation. The models are verified with the simulations and compared to the state-of-the-art. They allow accurate performance predictions, and provide insights on the dimensioning and resource allocation for clusters.