Modeling of Adjacent Channel Interference in Heterogeneous Wireless Networks

This letter proposes a new model for the aggregate adjacent channel interference (ACI) received from nearby terminal stations (TSs) of heterogeneous wireless networks. It is well known that lognormal distribution approximates the aggregate received signal, but we found that it does not perform well for ACI-modeling among coexisting TSs. We propose a weighted sum of lognormals-based approximation (WSLA) where the probability density function (PDF) of the aggregate ACI appears in the form of a weighted sum of lognormals. The closed-form downlink outage probabilities with both lognormal approximation and WSLA are also derived. Through simulations, we demonstrate that the proposed approximation outperforms the lognormal one. The WSLA can also be applied to a dual slope channel model and extended to model the aggregate interference in inter-cells or sensor networks.