Meilin He;Mingjue Zhu;Zhaoyang Zhang;Rui Guo;Haiquan Wang
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引用次数: 0
Abstract
An analytical expression of the check nodes (CNs) degree in a two-user regular Low-Density Parity-Check (LDPC) code is derived over a Gaussian multiple access channel, and a Fixed Point Analysis (FPA) method is developed to determine the optimal degree distribution that maximizes the achievable sum rate of the system. Specifically, firstly, an analytical expression of the CNs degree is derived as a function of mutual information outputs. Secondly, based on this, a reliable region is obtained by taking a complement of a unified unreliable region. Finally, the optimal degree distribution is determined over this reliable region to achieve the optimal sum rate. Numerical results indicate that the proposed method offers superior accuracy and much lower computational complexity compared to the extrinsic information transfer (EXIT) chart.
期刊介绍:
The IEEE Communications Letters publishes short papers in a rapid publication cycle on advances in the state-of-the-art of communication over different media and channels including wire, underground, waveguide, optical fiber, and storage channels. Both theoretical contributions (including new techniques, concepts, and analyses) and practical contributions (including system experiments and prototypes, and new applications) are encouraged. This journal focuses on the physical layer and the link layer of communication systems.