A Simple Capacity-Achieving Scheme for Channels with Polarization-Dependent Loss

We demonstrate, for a widely used model of channels with polarization dependent loss (PDL), that channel capacity is achieved by a simple interference cancellation scheme in conjunction with a universal precoder. Crucially, the proposed scheme is not only information-theoretically optimal, but it is also exceptionally simple and concrete. It transforms the PDL channel into separate scalar additive white Gaussian noise channels, allowing off-the-shelf coding and modulation schemes designed for such channels to approach capacity. The signal-to-noise ratio (SNR) penalty incurred under 6 dB of PDL is reduced to the information-theoretic minimum of a mere 1 dB as opposed to the 4 dB SNR penalty incurred under naive over-provisioning.Comment: Submitted to Journal of Lightwave Technolog

Generalized Spatially-Coupled Product-Like Codes Using Zipper Codes With Irregular Degree

Zipper codes with irregular variable degree are studied. Two new interleaver maps -- chevron and half-chevron -- are described. Simulation results with shortened double-error-correcting Bose--Chaudhuri--Hocquenghem constituent codes show that zipper codes with chevron and half-chevron interleaver maps outperform staircase codes when the rate is below 0.86 and 0.91, respectively, at $10^{-8}$ output bit error rate operating point. In the miscorrection-free decoding scheme, both zipper codes with chevron and half-chevron interleaver maps outperform staircase codes. However, constituent decoder miscorrections induce additional performance gaps.Comment: 6 pages, 11 figures, paper accepted for the GLOBECOM 2023 Workshop on Channel Coding Beyond 5

Generalized Staircase Codes with Arbitrary Bit Degree

We introduce a natural generalization of staircase codes in which each bit is protected by arbitrarily many component codewords rather than two. This enables powerful energy-efficient FEC based on iterative decoding of Hamming components.Comment: Submitted to 2024 Optical Fiber Communication Conference (OFC 2024

Space–time Codes from Sum-rank Codes

Just as rank-metric or Gabidulin codes may be used to construct rate–diversity tradeoff optimal space–time codes, a recently introduced generalization for the sum-rank metric—linearized Reed–Solomon codes—accomplishes the same in the case of multiple fading blocks. In this thesis, we provide the first explicit construction of minimal delay rate–diversity optimal multiblock space–time codes as an application of linearized Reed–Solomon codes. We further provide sequential decoders for these codes and, more generally, space–time codes constructed from finite field codes. These decoders then enable a study of the performance of the constructed codes in simulation whereby we demonstrate that they can outperform full diversity alternatives at low SNRs as well as utilize significantly smaller constellations.M.A.S