Design of a broadband low-profile microstrip antenna with multi-layer substrates

In this paper, the authors present that the offset-FILP fed MSA which located the FILP from the center of the patch, can increase the height of the FILP and moderate the restriction of substrates thickness. The authors also show the relationship between the input impedance and the feeding geometry, and investigate the maximum bandwidth of the offset-FILP fed MSA as well as that of the original model. Finally, the authors show that the offset-FILP fed MSA can be effectively fabricated by using substrates of same thickness.