Proximity Coordinated Random Access (PCRA) for M2M Applications in LTE-A

A significant amount of research has been conducted on adapting 3GPP Long Term Evolution (LTE) and LTE-Advanced (LTE-A) random access to be more efficient for machine-to-machine (M2M) devices because of the huge number of such devices that may reside in each LTE/LTE-A cell. However, there are other attributes of M2M applications that can be used as the basis of independent efficiency improvements. One characteristic which has been overlooked thus far is the spatial and temporal correlations that often exist in the activity of neighboring M2M devices belonging to the same M2M application. In this paper, we illustrate how these correlations can be exploited by coordinating the preambles to be used by neighboring M2M devices to reduce the number of collisions during LTE-A random access, particularly in wireless sensor network (WSN) type applications. The technique is referred to as proximity coordinated random access (PCRA). Through simulation of an example local preamble coordination algorithm that can be executed autonomously by randomly deployed devices of the same M2M application, we demonstrate an increase in the efficiency of the random access process.