PERFORMANCE EVALUATION OF CODED MODULATION SCHEMES BASED ON BINARY LATTICES

We describe computational techniques for the evaluation of error proba bility of modulation schemes based on binary lattices and multilevel c oding. These techniques stem from the representation of a binary latti ce in the form of a trellis whose structure depends on the block codes on which the binary lattice is based. Multilevel coded modulation sch emes can also be described through a trellis; by combining with this t he trellis structure of the lattice constellation we obtain a single t rellis that can be used for maximum-likelihood decoding using the Vite rbi algorithm and for computing the error probability. An upper bound to error probability can be obtained from the transfer function of the trellis with suitable labels, and is applicable to both maximum-likel ihood and staged decoding.