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Planar Difference Functions

Combinatorics 2012-07-31 v2 Information Theory math.IT Quantum Physics

Abstract

In 1980 Alltop produced a family of cubic phase sequences that nearly meet the Welch bound for maximum non-peak correlation magnitude. This family of sequences were shown by Wooters and Fields to be useful for quantum state tomography. Alltop's construction used a function that is not planar, but whose difference function is planar. In this paper we show that Alltop type functions cannot exist in fields of characteristic 3 and that for a known class of planar functions, x3x^3 is the only Alltop type function.

Cite

@article{arxiv.1205.3310,
  title  = {Planar Difference Functions},
  author = {Joanne L. Hall and Asha Rao and Diane Donovan},
  journal= {arXiv preprint arXiv:1205.3310},
  year   = {2012}
}

Comments

Accepted to ISIT2012. v2 added a reference and adjusted margins

R2 v1 2026-06-21T21:04:17.062Z