Asymptotic analysis of sum-rate under SIC

TL;DR

This paper provides a theoretical analysis of the asymptotic sum-rate performance of Successive Interference Cancellation (SIC) in large-scale IoT networks, revealing deterministic behavior as the number of nodes grows infinitely large.

Contribution

It introduces a general asymptotic framework for SIC performance in large networks, applicable to any channel gain distribution with power control, and characterizes the limiting distribution of decoded packets.

Findings

Asymptotic sum-rate characterized as number of transmitters grows large

Distribution of correctly decoded packets becomes deterministic asymptotically

Framework applicable to any channel gain distribution with equal average received power

Abstract

Limitation of the cost of coordination and contention among a large number of nodes calls for grant-free approaches, exploiting physical layer techniques to solve collisions. Successive Interference Cancellation (SIC) is becoming a key building block of multiple access channel receiver, in an effort to support massive Internet of Things (IoT). In this paper, we explore the large-scale performance of SIC in a theoretical framework. A general model of a SIC receiver is stated for a shared channel with $n$ transmitters. The asymptotic sum-rate performance is characterized as $n \rightarrow \infty$, for a suitably scaled target Signal to Noise Interference Ratio (SNIR). The probability distribution of the number of correctly decoded packets is shown to tend to a deterministic distribution asymptotically for large values of $n$. The asymptotic analysis is carried out for any probability distribution of the wireless channel gain, assuming that the average received power level is same for all nodes, through power control.