42 citations · 121 across the 18 of their papers we have counts for
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Hardness Results on Finding Leafless Elementary Trapping Sets and Elementary Absorbing Sets of LDPC Codes
Ali Dehghan, Amir H. Banihashemi
Leafless elementary trapping sets (LETSs) are known to be the problematic structures in the error floor region of low-density parity-check (LDPC) codes over the additive white Gaus…
From Cages to Trapping Sets and Codewords: A Technique to Derive Tight Upper Bounds on the Minimum Size of Trapping Sets and Minimum Distance of LDPC Codes
Ali Dehghan, Amir H. Banihashemi
Cages, defined as regular graphs with minimum number of nodes for a given girth, are well-studied in graph theory. Trapping sets are graphical structures responsible for error floo…
Asymptotic Average Multiplicity of Structures within Different Categories of Trapping Sets, Absorbing Sets and Stopping Sets in Random Regular and Irregular LDPC Code Ensembles
Ali Dehghan, Amir H. Banihashemi
The performance of low-density parity-check (LDPC) codes in the error floor region is closely related to some combinatorial structures of the code's Tanner graph, collectively refe…
Is there any polynomial upper bound for the universal labeling of graphs?
Arash Ahadi, Ali Dehghan, Morteza Saghafian
A {\it universal labeling} of a graph is a labeling of the edge set in such that in every orientation of for every two adjacent vertices and , the sum of…
Algorithmic complexity of proper labeling problems
Ali Dehghan, Mohammad-Reza Sadeghi, Arash Ahadi
A proper labeling of a graph is an assignment of integers to some elements of a graph, which may be the vertices, the edges, or both of them, such that we obtain a proper vertex co…
Algorithmic Complexity of Weakly Semiregular Partitioning and the Representation Number
Arash Ahadi, Ali Dehghan, Mohsen Mollahajiaghaei
A graph is {\it weakly semiregular} if there are two numbers , such that the degree of every vertex is or . The {\it weakly semiregular number} of a graph , deno…
On the Tanner Graph Cycle Distribution of Random LDPC, Random Protograph-Based LDPC, and Random Quasi-Cyclic LDPC Code Ensembles
Ali Dehghan, Amir H. Banihashemi
In this paper, we study the cycle distribution of random low-density parity-check (LDPC) codes, randomly constructed protograph-based LDPC codes, and random quasi-cyclic (QC) LDPC…