Reliable Transmission of Short Packets through Queues and Noisy Channels under Latency and Peak-Age Violation Guarantees

TL;DR

This paper analyzes the probability of delay and peak-age violations in short packet transmissions over queues and noisy channels, providing exact finite-blocklength characterizations for designing ultra-reliable low-latency systems.

Contribution

It introduces a finite-blocklength analysis of delay and peak-age violation probabilities using variable-length stop-feedback coding, avoiding large-deviation approximations.

Findings

Violation probabilities depend on frame size and error probability.

Numerical results guide system parameter choices for reliability.

Analysis aids in designing low-latency ultra-reliable communication systems.

Abstract

This work investigates the probability that the delay and the peak-age of information exceed a desired threshold in a point-to-point communication system with short information packets. The packets are generated according to a stationary memoryless Bernoulli process, placed in a single-server queue and then transmitted over a wireless channel. A variable-length stop-feedback coding scheme---a general strategy that encompasses simple automatic repetition request (ARQ) and more sophisticated hybrid ARQ techniques as special cases---is used by the transmitter to convey the information packets to the receiver. By leveraging finite-blocklength results, the delay violation and the peak-age violation probabilities are characterized without resorting to approximations based on large-deviation theory as in previous literature. Numerical results illuminate the dependence of delay and peak-age violation probability on system parameters such as the frame size and the undetected error probability, and on the chosen packet-management policy. The guidelines provided by our analysis are particularly useful for the design of low-latency ultra-reliable communication systems.