Downlink analysis for a heterogeneous cellular network

Abstract

Abstract-In this paper, a comprehensive study of the the downlink performance in a heterogeneous cellular network (or hetnet) is conducted. A general hetnet model is considered consisting of an arbitrary number of open-access and closed-access tier of base stations (BSs) arranged according to independent homogeneous Poisson point processes. The BSs of each tier have a constant transmission power, random fading coefficient with an arbitrary distribution and arbitrary path-loss exponent of the power-law path-loss model. For such a system, analytical characterizations for the coverage probability and average rate at an arbitrary mobile-station (MS), and average per-tier load are derived for both the max-SINR connectivity and nearest-BS connectivity models. Using stochastic ordering, interesting properties and simplifications for the hetnet downlink performance are derived by relating these two connectivity models to the maximum instantaneous received power (MIRP) connectivity model and the maximum biased received power (MBRP) connectivity models, respectively, providing good insights about the hetnets and the downlink performance in these complex networks. Furthermore, the results also demonstrate the effectiveness and analytical tractability of the stochastic geometric approach to study the hetnet performance.

A Primer on Cellular Network Analysis Using Stochastic Geometry

“…Therefore, the coverage probability of the derived PPP can by obtained by (35) with λ replaced by λ D which is also the coverage probability of the original PPP. Interested reader is advised to refer to the following representative set of works that use this general idea: [19], [20], [21], [22], [23], [24], [25].…”

“…Technically, assuming Rayleigh fading for only the serving link is sufficient to express the coverage probability in terms of the Laplace transform of interference, which means the fading distribution for the interfering links can be generalized without loss of tractability, as done in [1]. The generalization of the fading distribution for the serving link is usually much more complex [21], [22]. One key exception is when the channel power gain of the serving link is chosen from the exponential family, in particular, Gamma distribution (e.g., Nakagami-m).…”

“…This was discussed in Section III-G in the context of incorporating shadowing in the downlink analysis. For the application of this general idea to other scenarios, please refer to [19], [20], [21], [22], [23], [24], [25] and the references therein.…”

From 5G to 6G

“…As shown in Madhusudhanan et al [21], as the number of BS antennas is very large (𝑀 → ∞), the effects of uncorrelated noise and fast fading vanish completely, and there is no interference between data transmissions inside a cell. So, the simplest linear precoders and detectors are proved to be optimal.…”