Shared Aperture Dual-Wideband Planar Antenna Arrays Using Any-Layer PCB Technology for mm-Wave Applications

A novel strategy is proposed to design microstrip antenna arrays with two wide bands for high-frequency applications using any-layer HDI PCB technology. This technology makes it possible to stack multiple layers of substrates and microvias. Several antennas are designed and taped out to illustrate the new procedure. The antennas cover two wide frequency bands with a large separation ratio of 2.2:1, from 28 to 30 GHz and from 57 to 71 GHz. Measurement results show a matching better than 10 dB over both bands, and an intraband coupling lower than −28 dB. Measured gains and radiation patterns for the arrays all show a good agreement with simulations.