Statistical QoS provisioning for MTC Networks under Finite Blocklength

TL;DR

This paper derives a mathematical approximation for the effective capacity of delay-constrained MTC networks in finite blocklength regimes, analyzing the impact of SINR, delay, and reliability, and proposing methods to restore capacity.

Contribution

It provides a novel closed-form approximation for effective capacity in finite blocklength MTC networks and introduces three methods for capacity restoration under interference.

Findings

Higher reliability achievable with limited capacity sacrifice for small number of machines

SINR variations have less impact on strict delay constrained networks

Joint compensation effectively restores capacity with combined power control and delay degradation

Abstract

This paper analyzes the effective capacity of delay constrained machine type communication (MTC) networks operating in the finite blocklength regime. First, we derive a closed-form mathematical approximation for the effective capacity in quasi-static Rayleigh fading channels. We characterize the optimum error probability to maximize the concave effective capacity function with reliability constraint and study the effect of signal-to-interference-plus-noise ratio (SINR) variations for different delay constraints. The trade off between reliability and effective capacity maximization reveals that we can achieve higher reliability with limited sacrifice in effective capacity specially when the number of machines is small. Our analysis reveals that SINR variations have less impact on effective capacity for strict delay constrained networks. We present an exemplary scenario for massive MTC access to analyze the interference effect proposing three methods to restore the effective capacity for a certain node which are power control, graceful degradation of delay constraint and joint compensation. Joint compensation combines both power control and graceful degradation of delay constraint, where we perform maximization of an objective function whose parameters are determined according to delay and SINR priorities. Our results show that networks with stringent delay constraints favor power controlled compensation and compensation is generally performed at higher costs for shorter packets.