Size reduction and dual mode degeneracy in microstrip patch antenna using periodically rippled silicon substrate

A novel fabrication process for periodically rippled transmission lines is presented in this paper. This technique allows for height modulation of microstrip passive components, resulting in size reduction as well as dual mode degeneracy. A 4 mm × 4 mm X-band one dimensional (1D) rippled patch antenna with 6 µm periodicity is designed and fabricated using this technique. A 26% size reduction compared to regular antennas, as well as dual-mode operation is demonstrated in measurements. The measurement results confirm the potential application of the proposed structure in the design of compact dual-band integrated devices on silicon substrates.