2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/230973Polar codes, introduced recently by Arıkan, are the first family of codes known to achieve capacity of symmetric channels using a low complexity successive cancellation decoder. Although these codes, combined with successive cancellation, are optimal in this respect, their finite-length performance is not record breaking. We discuss several techniques through which their finite-length performance can be improved. We also study the performance of these codes in the context of source coding, both lossless and lossy, in the single-user context as well as for distributed applications.accepted in ISIT 2009, Figure 5 is different from the previous versionInformation Theorytext