A Multi-Objective Optimization Framework for URLLC with Decoding Complexity Constraints

TL;DR

This paper develops a multi-objective optimization framework for URLLC that balances reliability, latency, and decoding complexity, optimizing transmission parameters for low-power IoT devices.

Contribution

It introduces a novel MOOP approach considering decoding complexity constraints and derives the Pareto boundary for optimal transmission design in URLLC.

Findings

The MOOP effectively balances reliability, latency, and complexity.

Pareto-optimal transmission pairs improve energy efficiency.

Case study shows significant battery savings over fixed strategies.

Abstract

Stringent constraints on both reliability and latency must be guaranteed in ultra-reliable low-latency communication (URLLC). To fulfill these constraints with computationally constrained receivers, such as low-budget IoT receivers, optimal transmission parameters need to be studied in detail. In this paper, we introduce a multi-objective optimization framework for the optimal design of URLLC in the presence of decoding complexity constraints. We consider transmission of short-blocklength codewords that are encoded with linear block encoders, transmitted over a binary-input AWGN channel, and finally decoded with order-statistics (OS) decoder. We investigate the optimal selection of a transmission rate and power pair, while satisfying the constraints. For this purpose, a multi-objective optimization problem (MOOP) is formulated. Based on the empirical model that accurately quantifies the trade-off between the performance of an OS decoder and its computational complexity, the MOOP is solved and the Pareto boundary is derived. In order to assess the overall performance among several Pareto-optimal transmission pairs, two scalarization methods are investigated. To exemplify the importance of the MOOP, a case study on a battery-powered communication system is provided. It is shown that, compared to the classical fixed rate-power transmissions, the MOOP provides the optimum usage of the battery and increases the energy efficiency of the communication system while maintaining the constraints.