Beam-Switching Dual-Spherical Lens Antenna With Low Scan Loss at 71–76 GHz

A millimeter-wave communication system needs a directive beam-steering antenna with a low scan loss to compensate the high free space loss. In this letter, an electronically beam-switching integrated lens antenna (ILA) system with low scan loss is designed for lower E-band (71-76 GHz). An ILA with hemispherical collimating surface of 26 mm radius and spherical feed surface of 37.5 mm radius is fabricated from Teflon material. A conformal 1 × 16 linear beam-switching feed array based on SP4T switches and Vivaldi antennas is designed. The maximum simulated and measured realized gain including the switch network losses is 21.8 and 19.6 dBi, respectively. The measured scan loss of the ILA excluding the switch network loss is less than 1.3 dB in the lower E-band for beams within $\pm$ 40°.