Performance assessment and design of finite length LDPC codes for the Gaussian wiretap channel
This work addresses the need for secure communication codes in real-world applications, offering a practical solution for finite-length scenarios, though it is incremental as it builds on existing asymptotic studies.
The authors tackled the problem of designing practical LDPC codes for the Gaussian wiretap channel in finite-length regimes, achieving performance close to asymptotic limits with codewords around 10,000 bits.
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).