22 research outputs found
On the distribution of the output error burst lengths for Viterbi decoding of convolutional codes
The distribution of the output error burst lengths from a Viterbi decoder is of particular interest in connection with concatenated coding systems, where the inner code is convolutional. From the expurgated, random, and sphere-packing exponents for block codes an upper bound on this distribution for the ensemble of periodically time-varying convolutional codes is obtained. Finally, the distribution obtained from simulating time-invariant convolutional codes is presente
On coded modulation using LDPC convolutional codes
A new construction combining LDPC convolutional codes and multilevel coding/modulation is suggested and analyzed. In the case of QPSK, we demonstrate that it has a better performance than an LDPC convolutional code combined with conventional Gray mapping
Encoders and Decoders for Braided Block Codes
We consider construction and realization aspects of encoders and decoders for braided block codes (BBCs), which are a powerful class of iteratively decodable codes. An efficient encoder is proposed as well as a pipeline decoder realization. Also, upper and lower bounds on the free distance of BBCs are derived