Performance assessment and design of finite length LDPC codes for the Gaussian wiretap channel

TL;DR

This paper evaluates the reliability and secrecy of finite-length LDPC codes over the Gaussian wiretap channel, proposing a performance measurement approach and an optimization algorithm to design codes close to theoretical limits at practical lengths.

Contribution

It introduces a method to assess finite-length LDPC code performance and a new code design algorithm for improved secrecy and reliability in the Gaussian wiretap channel.

Findings

Proposed a performance measurement approach for finite-length LDPC codes.

Developed an optimization algorithm for designing irregular LDPC codes.

Achieved codes that approach asymptotic performance limits at moderate code lengths.

Abstract

In this work we study the reliability and secrecy performance achievable by practical LDPC codes over the Gaussian wiretap channel. While several works have already addressed this problem in asymptotic conditions, i.e., under the hypothesis of codewords of infinite length, only a few approaches exist for the finite length regime. We propose an approach to measure the performance of practical codes and compare it with that achievable in asymptotic conditions. Moreover, based on the secrecy metrics we adopt to achieve this target, we propose a code optimization algorithm which allows to design irregular LDPC codes able to approach the ultimate performance limits even at moderately small codeword lengths (in the order of 10000 bits).