Numerical Modeling and Experimental Validation of a D-band Lens-Based Antenna Design for Beyond 5G Communications

The interest for mm- and sub-mm-wave systems has grown in the last years, mostly driven by communications and radar industries. In particular, the new generations of communications systems, for 5G and beyond, put the focus in the use of these higher frequency bands, exploiting the large bandwidth availability to enable higher data rates. In this context, not only new wide-band high-gain antenna concepts are needed but also advances in the applied antenna measurement procedures. In this work, a high efficiency D-band lens antenna design with gain larger than 30 dB over 42% bandwidth is presented, which can be applied in point-to-multipoint communication scenarios. The radiation patterns and gain are characterized by means of a spherical distributed-axis scanner, built in a compact anechoic chamber. The elevation arm of the scanner is equipped with a new active dual-polarized probe, with integrated down-converters and diplexers. The introduced technology allows measurements from a 110 to 170 GHz with a dynamic range better than 65 dB (1 kHz RBW, normalized to 0 dBi DUT gain). The agreement with full-wave simulations is excellent over the whole frequency band for the broadside beam, as well as tilted ones. The antenna S-parameters have been as well evaluated, validating full-wave simulation results.