Paper to be presented at EUSIPCO 2022

The paper "Coherence-based subspace packings for MIMO noncoherent communications" will be presented at the 30th European Signal Processing Conference (EUSIPCO 2022) that will be held in Belgrade, Serbia, 29 Aug-2 Sep 2022. The paper is authored by J. Alvarez-Vizoso, Diego Cuevas, Carlos Beltran, Ignacio Santamaria, Vit Tucek and Gunnar Peters.

Abstract.- In this paper, we propose a new algorithm for designing unstructured Grassmannian constellations for noncoherent MIMO communications over Rayleigh block-fading channels. The algorithm minimizes the maximum coherence between subspaces, which is shown to be equivalent to the diversity product previously proposed in the literature. The coherence criterion is optimized by means of a gradient ascent algorithm on the Grassmann manifold. The method is generalized to optimize a weighted cost function that takes into account several neighboring codewords. Simulation results suggest that the constellations designed with the proposed algorithm achieve better SER performance than existing algorithms for unstructured Grassmannian constellation designs.