A hybrid thin film multilayer antenna for automotive radar is presented in this work. A 2 × 8 aperture coupled stacked patch antenna array is realized on a single layer printed circuit board (PCB) using a novel thin film-based approach. Using a compact 180° phase difference power divider, inter-element spacing in a 2×2 sub-array is reduced. Measurement results show a 19% (67.9–82.5 GHz) impedance bandwidth and a wideband broadside radiation pattern, with a maximum gain of 15.4 dBi realized gain at 72 GHz. The presented antenna compares favorably with other multilayer PCB antennas in terms of performance, with the advantage of simpler manufacturing and robust design. The antenna can be employed in mid-range automotive radar applications.

This paper presents two feeding techniques for the radiation characterization of integrated antennas at millimeter-wave frequencies. The first method involves feeding the antenna-under-test (AUT) with a radiofrequency (RF) probe. We compare the measurements obtained with a standard RF probe, an extended probe, and an extended probe with reversed connector orientation. We find that the reversed orientation probe produces the best results in terms of effective measurement angular sector and reduction of ripples due to diffraction. The second method involves feeding the AUT through a flexible transmission line. This method achieves a larger range of measurement angles, but still suffers from parasitic scattering likely due to the mounting bracket and still need further development.