International Journal of Mathematics and Mathematical Sciences
Volume 2003 (2003), Issue 15, Pages 935-946
doi:10.1155/S0161171203203124
On the structure of multipliers of ℤ2
Edgar Martínez-Moro1
and Roberto Canogar-Mckenzie2
1Departamento de Matemática Aplicada Fundamental, Universidad de Valladolid, Valladolid, Spain
2Departamento de Matemáticas, Universidad Nacional deEducación a Distancia (UNED), Madrid, Spain
Abstract
We show the combinatorial structure of ℤ2 modulo sublattices similar to ℤ2. The tool we use for dealing with this purpose is the notion of association scheme. We classify when the scheme defined by the lattice is imprimitive and characterize its decomposition in terms of the decomposition of the Gaussian integer defining the lattice. This arises in the classification of different forms of tiling ℤ2 by lattices of this type. The main application of these structures is that they are closely related to two-dimensional signal constellations with a Mannheim metric in the coding theory.