Multidimensional Multilevel Coding for Satellite Broadcasting with Highly Flexible QoS

We introduce the use of multidimensional (MD) constellations in a multilevel coding (MLC) scheme with multi-stage decoding (MSD) designed for broadcasting communications, where services with different quality of service (QoS) are desirable. We show that the number of different protection levels increases when using MD constellations. Besides, the appropriate block labeling (BL) partitioning for an MD constellation is found by applying the binary switching algorithm (BSA) as an efficient search algorithm. Two cost functions for the BSA are proposed based on the BL criterion. Some methods to construct an appropriate MD constellation are presented, including the use of uniform and non-uniform component constellations. The viability of the proposed MD constellations approach for broadcasting with different protection levels is evaluated analyzing the mutual information (MI) of each level. Finally, we present a comparison between a unidimensional and a multidimensional scheme which again demonstrates the benefits of the proposed scheme.