An Empirical Approach for Design of Wideband, Probe-Fed, U-Slot Microstrip Patch Antennas on Single-layer, Infinite, Grounded Substrates

Wideband microstrip antennas with relatively simple topologies continue to attract attention for design of compact, high-performance communication systems. The coaxially-fed, rectangular patch U-slot has recently been investigated numerically and experimentally, and shown to yield 10 dB return-loss bandwidths in excess of 20%. How- ever there are no analytical models, nor any systematic de- sign procedures currently available that can aid realizing these configurations. To that end, based on extensive CAD simulation results for a wide range of commercially avali- able microwave substrates ( to ), an empirical design methodology is derived and illustrated by examples. It is shown that the present empirical design technique, with its attendant limitations, generate wideband U-Slot designs that are optimized using CAD tools such as IE3D within a few iterations, resulting in substantially reduced overall process cycles.