On Node Density - Outage Probability Tradeoff in Wireless Networks

A statistical model of interference in wireless networks is considered, which is based on the traditional propagation channel model, a Poisson model of random spatial distribution of the nodes in 1-D, 2-D and 3-D spaces (with both uniform and non-uniform densities), and a threshold-based model of the receiver performance. The power of the dominant interferer is used as a major performance indicator, instead of a traditionally-used aggregate interference power, since the former is an accurate approximation of the latter. This simplifies the problem significantly so that compact closed-form expressions are obtained for the outage probability, including the case when a given number of strongest interferers are suppressed: the outage probability is shown to scale down exponentially in this number. The effect of Rayleigh and log-normal fading can also be included in the analysis. The positive effect of linear filtering (e.g. by directional antennas) is quantified via a new statistical selectivity parameter. The analysis culminates in formulation of an explicit tradeoff relationship between the network density and the outage probability, which is a result of the interplay between random geometry of node locations, the propagation path loss and the distortion effects at the victim receiver.