Description

As part of the 5G communication paradigm, ultra reliable communication (URC) is envisaged as an important technology pillar for providing anywhere and anytime services to end users. While most existing studies on reliable communication do not investigate this problem from a dependability theory perspective, those dependability based studies tend to define reliability merely in the time domain. In this letter, we advocate extending the concept of URC from the dependability perspective also in the space domain. We initiate definitions on cell availability and system availability. Correspondingly, the availability as well as the probability of providing a guaranteed level of availability in a network are analyzed both/either cell-wise and/or systemwise. Poisson point process (PPP) and Voronoi tessellation are adopted to model the spatial characteristics of cell deployment in both homogeneous and heterogeneous networks.