Impedance Measurements and Calculations of a Microstrip-Fed Slot Antenna on a Multilayered Electrically Thick Dielectric Substrate

This paper presents impedance calculations and measurements of a microstrip-fed slot antenna fabricated on a layered dielectric substrate as shown in Figure 1. This structure could be very useful for fabricating imaging array antenna structures for high millimeter wave frequencies because it allows the antenna array to be fabricated on a substrate that can be electrically thick. The radiation properties of slots and dipoles on electrically thick, layered substrates have been discussed in [1-3] but this is the first presentation of experimental and calculated results of impedance for these structures. We show measurements and calculations for 2 structures. A single supporting substrate, and a three layer supporting substrate. The measurements were made at X-band using an 8510B network analyzer, and the calculations were performed using a spectral domain method in conjunction with a reciprocity method [4].