Rate-Compatible Serially Concatenated Codes with Outer Extended BCH Codes

In this paper, we propose a rate-compatible serially concatenated structure consisting of an outer linear extended BCH code and an inner recursive systematic convolutional code. Rate flexibility is achieved by puncturing the inner code. A two- step code design procedure combining analytical union bounds with Extrinsic Information Transfer charts is used to obtain codes offering very good performance in both the waterfall and the error floor regions over a wide range of code rates. The resulting codes show interesting advantages in terms of convergence and error floor compared to similar structures using convolutional codes as outer codes.