When Every Symbol Counts: Resilient Wireless Systems Under Finite Blocklength Constraints

TL;DR

This paper investigates how finite blocklength constraints impact the resilience of 6G wireless systems, proposing RIS-assisted strategies to optimize recovery and demonstrate critical blocklength thresholds for effective disruption management.

Contribution

It introduces a framework analyzing FBL effects on wireless resilience and shows how RIS can mitigate performance loss, identifying key blocklength thresholds for optimal recovery.

Findings

Two critical blocklength thresholds enable full recovery from FBL penalties and disruptions.

RIS elements can shift thresholds, allowing faster reconfiguration with shorter blocklengths.

Numerical results demonstrate trade-offs between rate, blocklength, and reconfiguration effort.

Abstract

As 6G evolves, wireless networks become essential for critical operations and enable innovative applications that demand seamless adaptation to dynamic environments and disruptions. Because these vital services require uninterrupted operation, their resilience to unforeseen disruptions is essential. However, implementing resilience necessitates rapid recovery procedures, which operate in the finite blocklength (FBL) regime, where short packets and added error-correction overhead can severely degrade communication efficiency. Due to this performance loss, always attempting recovery can backfire and result in worse outcomes than simply enduring the disruption under longer blocklengths. In this work, we study these effects of FBL constraints within a resilience framework, incorporating reconfigurable intelligent surfaces (RIS) to enhance adaptation capabilities. By actively shaping the wireless environment, RIS help counteract some of the performance losses caused by FBL, enabling more effective recovery from disruptions. Numerical results reveal two critical blocklength thresholds: the first enables full recovery from the FBL penalty, while the second, at a higher blocklength, allows the system to recover from both the FBL penalty and the initial disruption, yielding a significant improvement in resilience performance. Additionally, we show that the number of RIS elements shifts these thresholds, enabling faster reconfiguration with shorter blocklengths and providing insights to the trade-offs between rate, blocklength, and reconfiguration effort under FBL conditions.