@article{ author = {E. Bj\"{o}rnson and H. Wymeersch and B. Matthiesen and P. Popovski and L. Sanguinetti and E. de Carvalho}, year = {2021}, month = {Feb}, title = { Reconfigurable Intelligent Surfaces: A Signal Processing Perspective With Wireless Applications}, URL = {https://arxiv.org/abs/2102.00742}, journal={IEEE Signal Processing Magazine, to appear} }