Design of LTCC patch antenna for increased bandwidth and reduced susceptibility to fabrication process inaccuracies

Abstract

This paper presents three 120 GHz low temperature co-fired ceramics (LTCC) microstrip antenna designs with different performance to complexity ratio. The first one is a simple one layer rectangular patch with narrow (4.9%) bandwidth, given for reference purpose. In second construction dielectric-filled cavity is used for bandwidth enhancement to 10% Third antenna is further improved by application of optimized, wideband microstrip feed line width transition at cavity boundary. Several designs of the transition are evaluated with electromagnetic simulation considering their performance, complexity and resistance to manufacturing inaccuracies. The two-step gradual transition with moderate complexity and satisfactory performance is used in the third antenna design resulting with improved resistance to manufacturing inaccuracies and 12.5% bandwidth.