161 citations · 236 across the 12 of their papers we have counts for
21 papers
Graph Search based Polar Code Design
Marvin Geiselhart, Andreas Zunker, Ahmed Elkelesh +2
It is well known that to fulfill their full potential, the design of polar codes must be tailored to their intended decoding algorithm. While for successive cancellation (SC) decod…
Learning Quantization in LDPC Decoders
Marvin Geiselhart, Ahmed Elkelesh, Jannis Clausius +4
Finding optimal message quantization is a key requirement for low complexity belief propagation (BP) decoding. To this end, we propose a floating-point surrogate model that imitate…
A Polar Subcode Approach to Belief Propagation List Decoding
Marvin Geiselhart, Ahmed Elkelesh, Jannis Clausius +1
Permutation decoding gained recent interest as it can exploit the symmetries of a code in a parallel fashion. Moreover, it has been shown that by viewing permuted polar codes as po…
Automorphism Ensemble Decoding of Quasi-Cyclic LDPC Codes by Breaking Graph Symmetries
Marvin Geiselhart, Moustafa Ebada, Ahmed Elkelesh +2
We consider automorphism ensemble decoding (AED) of quasi-cyclic (QC) low-density parity-check (LDPC) codes. Belief propagation (BP) decoding on the conventional factor graph is eq…
Iterative Reed-Muller Decoding
Marvin Geiselhart, Ahmed Elkelesh, Moustafa Ebada +2
Reed-Muller (RM) codes are known for their good maximum likelihood (ML) performance in the short block-length regime. Despite being one of the oldest classes of channel codes, find…
On the Automorphism Group of Polar Codes
Marvin Geiselhart, Ahmed Elkelesh, Moustafa Ebada +2
The automorphism group of a code is the set of permutations of the codeword symbols that map the whole code onto itself. For polar codes, only a part of the automorphism group was…
Iterative Detection and Decoding of Finite-Length Polar Codes in Gaussian Multiple Access Channels
Moustafa Ebada, Sebastian Cammerer, Ahmed Elkelesh +2
We consider the usage of finite-length polar codes for the Gaussian multiple access channel (GMAC) with a finite number of users. Based on the interleave-division multipleaccess (I…
Automorphism Ensemble Decoding of Reed-Muller Codes
Marvin Geiselhart, Ahmed Elkelesh, Moustafa Ebada +2
Reed-Muller (RM) codes are known for their good maximum likelihood (ML) performance in the short block-length regime. Despite being one of the oldest classes of channel codes, find…
CRC-Aided Belief Propagation List Decoding of Polar Codes
Marvin Geiselhart, Ahmed Elkelesh, Moustafa Ebada +2
Although iterative decoding of polar codes has recently made huge progress based on the idea of permuted factor graphs, it still suffers from a non-negligible performance degradati…
Deep Learning-based Polar Code Design
Moustafa Ebada, Sebastian Cammerer, Ahmed Elkelesh +1
In this work, we introduce a deep learning-based polar code construction algorithm. The core idea is to represent the information/frozen bit indices of a polar code as a binary vec…
Optimizing Polar Codes Compatible with Off-the-Shelf LDPC Decoders
Moustafa Ebada, Ahmed Elkelesh, Stephan ten Brink
Previous work showed that polar codes can be decoded using off-the-shelf LDPC decoders by imposing special constraints on the LDPC code structure, which, however, resulted in some…
Decoder-in-the-Loop: Genetic Optimization-based LDPC Code Design
Ahmed Elkelesh, Moustafa Ebada, Sebastian Cammerer +2
LDPC code design tools typically rely on asymptotic code behavior and are affected by an unavoidable performance degradation due to model imperfections in the short length regime.…
Decoder-tailored Polar Code Design Using the Genetic Algorithm
Ahmed Elkelesh, Moustafa Ebada, Sebastian Cammerer +1
We propose a new framework for constructing polar codes (i.e., selecting the frozen bit positions) for arbitrary channels, and tailored to a given decoding algorithm, rather than b…
Genetic Algorithm-based Polar Code Construction for the AWGN Channel
Ahmed Elkelesh, Moustafa Ebada, Sebastian Cammerer +1
We propose a new polar code construction framework (i.e., selecting the frozen bit positions) for the additive white Gaussian noise (AWGN) channel, tailored to a given decoding alg…
Belief Propagation List Decoding of Polar Codes
Ahmed Elkelesh, Moustafa Ebada, Sebastian Cammerer +1
We propose a belief propagation list (BPL) decoder with comparable performance to the successive cancellation list (SCL) decoder of polar codes, which already achieves the maximum…
Belief Propagation Decoding of Polar Codes on Permuted Factor Graphs
Ahmed Elkelesh, Moustafa Ebada, Sebastian Cammerer +1
We show that the performance of iterative belief propagation (BP) decoding of polar codes can be enhanced by decoding over different carefully chosen factor graph realizations. Wit…
Sparse Graphs for Belief Propagation Decoding of Polar Codes
Sebastian Cammerer, Moustafa Ebada, Ahmed Elkelesh +1
We describe a novel approach to interpret a polar code as a low-density parity-check (LDPC)-like code with an underlying sparse decoding graph. This sparse graph is based on the en…
Mitigating Clipping Effects on Error Floors under Belief Propagation Decoding of Polar Codes
Ahmed Elkelesh, Sebastian Cammerer, Moustafa Ebada +1
In this work, we show that polar belief propagation (BP) decoding exhibits an error floor behavior which is caused by clipping of the log-likelihood ratios (LLR). The error floor b…
Scattered EXIT Charts for Finite Length LDPC Code Design
Moustafa Ebada, Ahmed Elkelesh, Sebastian Cammerer +1
We introduce the Scattered Extrinsic Information Transfer (S-EXIT) chart as a tool for optimizing degree profiles of short length Low-Density Parity-Check (LDPC) codes under iterat…
Flexible Length Polar Codes through Graph Based Augmentation
A. Elkelesh, M. Ebada, S. Cammerer +1
The structure of polar codes inherently requires block lengths to be powers of two. In this paper, we investigate how different block lengths can be realized by coupling of several…
Improving Belief Propagation Decoding of Polar Codes Using Scattered EXIT Charts
A. Elkelesh, M. Ebada, S. Cammerer +1
For finite length polar codes, channel polarization leaves a significant number of channels not fully polarized. Adding a Cyclic Redundancy Check (CRC) to better protect informatio…