A GSG-Excited Ultra-Wideband 103–147 GHz Stacked Patch Antenna on Flexible Printed Circuit

An ultra-wideband aperture coupled stacked antenna operating in the WR08 band (90–140 GHz) is presented. The design consists of two rectangular stacked patches fed by a rectangular slot coupled to a stripline feed. A ground-signal-ground (GSG) probe pad configuration is included in the design to excite the antenna and perform wideband measurements. Ansys HFSS simulation tool is used for the simulation level design and the final layout is fabricated using the MFLEX modified polyimide (MPI) material. The simulated antenna achieves a −10 dB bandwidth of 44.9 GHz, with an average realized gain of 5.7 dBi and average efficiency of 73.9% across the bandwidth. To the best of our knowledge, this is the first antenna with more than 30% bandwidth fabricated on flexible printed circuit (FPC) technologies above 100 GHz.