Design of nonbinary quasi-cyclic low-density parity-check codes by maximising the minimum distance

In this paper, we propose a construction method of nonbinary quasi-cyclic low-density parity-check (QC-LDPC) codes. The shift offset values of the circulant permutation submatrices are selected not only by maximising the girth but also by maximising the minimum distance upper bound. The proposed method provides a more rational optimisation way than only maximising the girth. Copyright © 2012 John Wiley & Sons, Ltd. *Correspondence L. Liu, Wireless Information Network Lab, University of Science and Technology of China, Hefei, Anhui 230027, China. E-mail: [email protected] Received 1 April 2012; Revised 30 May 2012; Accepted 3 July 2012