In this paper we address the problem of decoding 2D convolutional codes over the erasure channel. To this end we introduce the notion of balls around a burst of erasures which can be considered an analogue of the notion of sliding window in the context of 1D convolutional codes. The main idea is to reduce the decoding problem of 2D convolutional codes to a problem of decoding a set of associate...

The paper starts with a short overview of channel coding and the reader is reminded the concept of convolutional encoding. Bottlenecks of the traditional approach are described and the motivation behind turbo codes is explained. After examining the turbo codes design more in detail, reasons behind their efficiency are brought out. Finally, a real-world example of the turbo code used in the thir...

In this work, we observe the behavior of block space-time code in wireless channel dynamics. The block space-time code is optimally constructed in slow fading. The block code in quasi-static fading channels provides affordable complexity in design and construction. Our results show that the performance of the block space-time code may not be as good as conventionally convolutional coding with s...

A permutor design for woven convolutional encoders with outer warp is introduced. All warp permutors are considered jointly, and for the overall design an approach similar to that of higher order separations for serially concatenated convolutional codes is applied. We present a bound on the minimum distance of a code generated by a woven convolutional encoder with outer warp and designed row pe...

Convolutional codes have been widely used in DS-CDMA systems for good performance and relatively low decoding complexity. In this article we, starting from the theoretical point, study the performance of convolutional codes in an environment where E b /N 0 changes sinu-soidally. We will study four cases of this scenario. For each case we obtain some conclusions and give their analysis. In this ...

SUMMARY In order to guarantee pairwise independence of codewords in an ensemble of convolutional codes it is necessary to consider time-varying codes. However, Seguin has shown [1] that the pairwise independence property is not strictly necessary when applying the random coding argument and on this basis he derives a new random coding bound for rate 1/n fixed convo-lutional codes [2]. In this p...

Cooperative communication using relay nodes is one of the most effective means of exploiting space diversity for low cost nodes in wireless network. In cooperative communication, users, besides communicating their own information, also relay the information of other users. In this paper we investigate a scheme where cooperation is achieved using a common relay node which performs network coding...

Space-time convolutional codes have shown considerable promise for providing improved performance for wireless communication through combined diversity and coding gain. An eecient design procedure is presented here for optimizing the coding and diversity gain measures proposed in the rst papers on space-time codes. The procedure is based on some simple lower and upper bounds on coding gain. The...

For low-rate trellis codes that do not utilize uncoded bits, a new approach to constellation labeling which maximizes the constellation edge proole can provide improved metrics. We investigate the edge proole optimality for 8-QAM and 32-QAM constellations. The labeling structures that achieve the optimal edge prooles for 8-QAM and 32-QAM are presented. Explicit proofs of the optimal edge proole...

This paper investigates the use of different transformations for improving the randomness of sequences. In particular, convolutional codes are used for increasing the size of a given sequence and then a random mapping function is used for further randomization. We have shown how such a method can convert highly correlated sequences into random ones.