New 16-PSK group trellis codes

The theory of group codes simplifies the construction of good rotationally invariant trellis codes for the additive white Gaussian noise channel. New geometrically uniform trellis codes, with spectral efficiency 3 bits/2D, based on multidimensional L/spl times/16-PSK constellations in 4, 6, and 8 dimensions, obtained by group trellis codes over nonbinary groups of the kind Z/sub 16//sup L/, are presented. Most of the codes improve, in terms of asymptotic gain and rotational invariance, the best codes known so far in the literature.<
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