Millimeter-wave Performance of Broadband Aperture Antenna on Laminates
Authors: Rashaunda Henderson, Richard Pierce, Supreetha Aroor, Joel Arzola, Christopher Miller, Harini Kumar, Thethnin Ei, Andrew Blanchard, Dave Fooshe, Bert Schluper, Dan Swan, Carlos Morales
This paper summarizes the design, fabrication and characterization of a coplanar waveguide fed modified aperture bowtie antenna operating in the 60 to 90 GHz range. Modifications to the bowtie edges extend the bandwidth up to 40% without increasing radiator area. The antenna was initially designed and measured in the 3-8 GHz frequency band and then frequency scaled to 60-90 GHz. The millimeter wave antenna is implemented on FR408 (r=3.65) and a multilayer laminate. Both substrates can be used in millimeter-wave system design where efficient antennas are needed. Return loss measurements of the antennas are made on a Cascade probe station. The results agree well with simulations in ANSYS HFSS. Until recently, only simulated radiation patterns were available illustrating broadside gain of 5 to 7 dB for these antennas. With the acquisition of a spherical scanner, near-field measurements have been taken of the three antennas from 67 to 110 GHz. The broadside radiation pattern results are compared with simulation. The NSI 700S-360 spherical near-field measurement system used in conjunction with an Agilent network analyzer, GGB Picoprobes and Cascade manipulator allow for on-wafer measurements of the antenna under test.