Code Design with EXIT Charts

Iterative decoding provides high performance at low complexity for many state-of-the-art codes, like turbo codes, low-density parity-check (LDPC) codes, and irregular repeat accumulate codes, as well as for many iterative receiver structures. In order to achieve such high performance, the codes need to be designed such that iterative decoding works well. The extrinsic information transfer (EXIT) chart method is a powerful tool to analyze the iterative decoding process and to accomplish the required code design. Furthermore, it provides intuition for the decoding process, and allows to formulate the code design problem in many cases as a convex optimization problem.