The diversity product and the diversity sum are two very important parameters
for a good-performing unitary space time constellation. A basic question is
what the maximal diversity product (or sum) is. In this paper we are going to
derive general upper bounds on the diversity sum and the diversity product for
unitary constellations of any dimension n and any size m using packing
techniques on the compact Lie group U(n).Comment: 15 pages, 3 figures, submitted to IEEE trans. inf