  In this paper, we propose a new structured Grassmannian constellation for
noncoherent communications over single-input multiple-output (SIMO) Rayleigh
block-fading channels. The constellation, which we call Grass-Lattice, is based
on a measure preserving mapping from the unit hypercube to the Grassmannian of
lines. The constellation structure allows for on-the-fly symbol generation,
low-complexity decoding, and simple bit-to-symbol Gray coding. Simulation
results show that Grass-Lattice has symbol and bit error rate performance close
to that of a numerically optimized unstructured constellation, and is more
power efficient than other structured constellations proposed in the literature
and a coherent pilot-based scheme.
