Woven codes with outer warp: Variations, design, and distance properties

In this paper, we consider convolutional and block encoding schemes which a re variations of woven codes with outer warp, We propose methods to evaluat e the distance characteristics of the considered codes on the basis of the active distances of the component codes. With this analytical hounding tech nique, we derived lower bounds on the minimum (or free) distance of woven c onvolutional codes, woven block codes, serially concatenated codes, and wov en turbo codes. Next, we show that the lower bound on the minimum distance can be improved if we use designed interleaving with unique permutation fun ctions in each row of the warp of the woven encoder. Finally, with the help of simulations, we get upper hounds on the minimum distance for some parti cular codes and then investigate their performance in the Gaussian channel, Throughout this paper, we compare all considered encoding schemes by means of examples, which illustrate their distance properties.