60 GHz polarimetric MIMO sensing: Architectures and technology
Millimeter-Wave (mm-W) is considered a potential technology for high-data rate wireless transmission and for high-resolution short-range radar, due to the 7-9 GHz bandwidth at the 60 GHz unlicensed band available worldwide. Developing ultrawideband architectures including multiple-input-multiple-output (MIMO) antenna systems at mm-W offer many advantages including jointly optimized analogue and digital signal processing at carrier frequency and baseband. This allows for flexible antenna designs and reduced losses, as many passive structures can be avoided at both sides of the link. Besides, based on flexible polarimetric approaches, the polarimetric propagation of electromagnetic waves can be exploited. In this paper we present a 60 GHz polarimetric MIMO system architecture, which includes analogue miniaturized frontends designed and manufactured by multi-layer packaging technologies. Such architecture permitted the design of compact MIMO radar and multi-dimensional channel sounding. The MIMO approach allows not only polarimetric filtering and fully polarimetric/directional signal processing to increase the signal-to-clutter-plus-noise ratio of mm-W radar systems, but also the full characterization of wireless channels including multipath with orthogonal polarizations.