Error floor Analysis of LT Codes over the Additive White Gaussian Noise Channel
2011 (English)In: 2011 IEEE GLOBAL TELECOMMUNICATIONS CONFERENCE (GLOBECOM 2011) , IEEE , 2011, 6133650- p.Conference paper (Refereed)
We investigate the error floor performance of Luby Transform (LT) codes over the additive white Gaussian noise channel. We first derive a lower bound on the bit error rate for an LT code, which we subsequently use to show that the corresponding error floor is predominantly caused by low-degree variable nodes. Based on this observation, we propose a modified encoding scheme for LT codes that provides a lower error floor with no increase in encoding and decoding complexities. The convergence behavior of the proposed scheme is analyzed using extrinsic information transfer charts, and shown to be similar to the original LT code. Numerical examples demonstrate the improvements of the modified LT code as a stand-alone code and as a component code of a Raptor code.
Place, publisher, year, edition, pages
IEEE , 2011. 6133650- p.
, Globecom. IEEE Conference and Exhibition, ISSN 1930-529X
IdentifiersURN: urn:nbn:se:kth:diva-63207DOI: 10.1109/GLOCOM.2011.6133650ISI: 000300509000148ScopusID: 2-s2.0-84857218656ISBN: 978-1-4244-9268-8OAI: oai:DiVA.org:kth-63207DiVA: diva2:481801
54th Annual IEEE Global Telecommunications Conference: 'Energizing Global Communications', GLOBECOM 2011;Houston, TX;5 December 2011through9 December 2011
QC 201202062012-01-222012-01-222012-10-23Bibliographically approved