Encontrados 8 documentos, a visualizar página 1 de 1

Constructive spherical codes by hopf foliations

Abstract: We present a new systematic approach to constructing spherical codes in dimensions 2k , based on Hopf foliations. Using the fact that a sphere S2n-1 is foliated by manifolds Sn-1cos r×Sn-1sin r , E [0,p/2] , we distribute points in dimension 2k via a recursive algorithm from a basic construction in R4 . Our procedure outperforms some current constructive methods in several small-distance regimes and c...

Algebraic constructions of rotated unimodular lattices and direct sum of Barnes...

Made available in DSpace on 2020-12-12T01:15:01Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-01-01; In this paper, we construct some families of rotated unimodular lattices and rotated direct sum of Barnes-Wall lattices BWn for n = 4, 8 and 16 via ideals of the ring of the integers azeta&2rq + ;zeta&2rq-1] for q = 3, 5 and 15. We also construct rotated BW16 and BW32-lattices via a;-submodules of azeta...

Algebraic construction of lattices via maximal quaternion orders

Made available in DSpace on 2020-12-12T00:54:56Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-05-01; Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); In this paper we propose a framework to construct algebraic lattices in dimensions 4n via ideals from ...

A note on quadrangular embedding of abelian cayley graphs

Agradecimentos: This work was partially supported by FAPESP-Brazil 2007/56052-8, 2007/00514-3, 2011/01096-6 and 2013/25977-7 and CNPq 309561/2009-4 and 304705/2010-1; Abstract: The genus graphs have been studied by many authors, but just a few results concerning in special cases: Planar, Toroidal, Complete, Bipartite and Cartesian Product of Bipartite. We present here a general lower bound for the genus of a ab...

Algebraic constructions of densest lattices

Abstract: The aim of this paper is to investigate rotated versions of the densest known lattices in dimensions 2, 3, 4, 5, 6, 7, 8, 12 and 24 constructed via ideals and free -modules that are not ideals in subfields of cyclotomic fields. The focus is on totally real number fields and the associated full diversity lattices which may be suitable for signal transmission over both Gaussian and Rayleigh fading chann...

Flap tori, lattices and bounds for commutative group codes

Uma introdução à teoria de códigos

Não disponível.

Aplicações não singulares de ordem P

Orientador : Antonio Conde; Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Matematica, Estatistica e Computação Científica; Resumo: Não informado; Abstract: Not informed; Doutorado; Doutor em Matemática