Capacity Analysis in the Next Generation Wireless Networks Based on SINR Constraints

The demand for accessing services while on the move, at any place and anytime, has led to the current efforts towards integration ofheterogeneous wireless networks. In particular, interoperability of cellular networks and Wireless Local Area Network (WLAN), as complementarysystems in providing capacity and coverage, has drawn a lot of attention. Next Generation Wireless Networks (NGWNs) are expected to be heterogeneous networks which integrate different Radio Access Technologies (RATs) such as 3GPP's Long Term Evolution (LTE) andWLANwhere a transmission is supported if the signal-to-interference-plus-noise ratio (SINR) at the receiver is greater than some threshold. It is based on the fact that several competing technologies, which have different requirements and capabilities, can co-exist. This approach tries to select always the best network according to a set of requirements and perform the inter-system handover between them, when those requirements are not fulfilled. In this article, we analyze the interference in heterogeneous wireless networks and determinethe capacity, in a study based on Markov chains, by taking into considerationthe class of traffic of each call and considering both intra-network interference and inter-network interference. Our analysis approach is based on modeling of the system as a multi-dimensional Markov chain which represents the current number of ongoing calls of different classes of services in the system. This analysis allows us to simplify the estimation of capacity under SINR interference constraints in different wireless networks. Based on this analysis, we derive performance evaluation results regarding blocking of real-time and non-real-time calls in each RAT and under different network sizes.