Balanced codes and nonequiprobable signaling

Author

Calderbank, A.R. ; Klimesh, M.

Author_Institution

AT&T Bell Lab.. Murray Hill, NJ, USA

Volume

38

Issue

3

fYear

1992

fDate

5/1/1992 12:00:00 AM

Firstpage

1119

Lastpage

1122

Abstract

The problem of shaping signal constellations that are designed for the Gaussian channel is considered. The signal constellation consists of all points from some translate of a lattice Λ that lie within a region R. The signal constellation is partitioned into T annular subconstellations Ω_o,…,Ω_T-1, by scaling the region R. Signal points in the same subconstellation are used equiprobably, and a shaping code selects region Ω_i with frequency f_i. If the signal constellation is partitioned into annular subconstellations of unequal size. then the transmission rate should vary with the choice of codeword in the shaping code. and it will be necessary to queue the data in buffers. It is described how the balanced binary codes constructed by D. E. Knuth (1986) can be used to avoid a data rate that is probabilistic. The basic idea is that if symbols 0 and 1 represent constellations of unequal size. and if all shaping codewords have equally many 0´s and 1´s, then the data rate will be deterministic

Keywords

codes; signalling (telecommunication networks); telecommunication channels; Gaussian channel; balanced binary codes; data rate; nonequiprobable signaling; shaping code; signal constellations; subconstellation; Associative memory; Computer networks; Constellation diagram; Lattices; Neural networks; Physics computing; Random variables; Region 1; Region 9; Shape measurement;

fLanguage

English

Journal_Title

Information Theory, IEEE Transactions on

Publisher

ieee

ISSN

0018-9448

Type

jour

DOI

10.1109/18.135651

Filename

135651