Design of 3D Antennas for 24 GHz ISM Band Applications

A novel three dimensional (3D) antenna is designed for 24 GHz frequency ISM band applications. The 3D antenna uses optimal 2D space and relies heavily on 3D structures to provide improved antenna performance. Four different 3D antenna configurations are studied to understand the improvement in the antenna design. The antenna parameters and surface current distribution are compared with patch antenna of 24 GHz frequency. The 3D configuration allows more space for device fabrication and enhance the chip functionalities. The 3D architecture consist of antenna, which is fed by quarter wave transmission line to match antenna impedance. A wave port is designed to characterize the antenna. The designed 3D antenna is compact as compared to 2D planar patch antenna of same frequency. In the 3D architecture, the current is distributed to the patch on a different plane via 3D conducting channels. The current distribution shows maximum current in the surface conducting layer for two types of the 3D antenna designed. The compact 3D antenna is designed to radiate at 24 GHz and occupies space of less than 3.75 mm × 3.75 mm in the die as compared to the space of 7.27 mm × 7.27 mm for planar patch antenna of similar frequency. The reduction in space offers wide advantages in designing on-chip RF systems. The simulation of the antennas were completed using An soft HFSS™, 3D electromagnetic tool.