[IEEE Trans. on Information Theory, November 2002, pp. 2980-2989]
Gaussian Source Coding with Spherical Codes
Jon Hamkins and Kenneth Zeger
Abstract
A fixed rate shape-gain quantizer for the memoryless Gaussian source is
proposed. The shape quantizer is constructed from wrapped spherical
codes that map a sphere packing in Rk-1 onto a sphere in
Rk, and the gain codebook is a globally optimal scalar quantizer.
A wrapped Leech lattice shape quantizer is used to demonstrate a signal
to quantization noise ratio within 1 dB of the distortion-rate
function for rates above 1 bit per sample, and an improvement over
existing techniques of similar complexity. An asymptotic analysis of
the tradeoff between gain quantization and shape quantization is also
given.