On Strictly Geometrically Uniform Codes: Construction and New Codes

Oscar Yassuo TAKESHITA  Hideki IMAI  

IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences   Vol.E80-A       pp.590-597
Publication Date: 1997/03/25
Online ISSN: 
Print ISSN: 0916-8508
Type of Manuscript: Category: Information Theory and Coding Theory
geometrically uniform codes,  group codes,  trellis code,  

Full Text: PDF>>
Buy this Article

Geometrically Uniform (GU) codes have been a center of attention because their symmetric properties along with group algebraic structure provide benefits on their design and perfomance evaluation. We have been following a class of GU codes tha we call Strictly Geometrically Uniform (SGU) codes. Our studies had started from devising a way to get SGU trellis codes from Non-SGU (NSGU) constellations. Essentially, SGU multidimensional constellations were derived from an 1- or 2-dimensional NSGU constellations. Some simple good codes were then found, and the novelty is that they rely on symmetries of permutation of channel symbols. Applying the same method to PSK-type constellations, which is SGU, yielded again good codes, along with results regarding their algebraic structure.