This example demonstrates how XFdtd simulates a 60 GHz cylindrical dielectric resonator antenna that is constructed on a silicon base to emulate on-chip designs. The antenna could be used for a wireless personal area network (WPAN), which would provide communication in the immediate vicinity of a user’s workspace. The antenna has a peak gain of about 2.5 dBi, a bandwidth of over 2.5 GHz, and positive gain of about +/- 55 degrees off boresight. The antenna design discussed here comes from a conference paper .
Device Design and Simulation
As the antenna is intended to be on-chip, it is simulated here by being attached to a section of a lossy silicon (relative permittivity 11.9, conductivity 10 S/m) block 1500 μm x 1500 μm x 250 μm. A 6.22 μm layer of SiO2 (relative permittivity 4) covers the top of the silicon block and is then covered by a 2 μm layer of conducting ground plane. A 50-ohm co-planar waveguide (CPW) feeds the resonator, which has a radius of 0.33 mm, a height of 0.3 mm, and a high relative permittivity of 48. Vias are installed between the ground plane and the silicon block around the CPW slots. The antenna geometry is visible in a three-dimensional CAD view in Figure 1 and a top-down view in Figure 2.
Following simulation, the return loss is found to have a deep null near 60 GHz (Figure 3) with a -10dB bandwidth of more than 2.5 GHz. The input impedance as a function of frequency is plotted in Figure 4, which shows a good match to 50 ohms at 60 GHz.
The gain of the antenna as a function of frequency at a point directly above the antenna (Figure 5) shows a peak gain of about 2.5 dBi at 60 GHz, which rolls off smoothly with positive gain at more than 4 GHz bandwidth. The radiation and system efficiencies of the antenna (with and without mismatch losses) show a peak of about 60% at 60 GHz (Figure 6) and the radiation pattern is nearly spherical with positive gain over a range of about 110 degrees (Figure 7). In the YZ and XZ planes (vertical cuts), the antenna has nearly uniform co-polarized gain (Figures 8 and 9) and much lower cross-polarized gain. The radiation pattern in the horizontal XY plane is shown in Figure 10.
The high permittivity dielectric resonator of the antenna is able to operate with much lower losses than a metallic antenna, resulting in higher efficiency while still providing good broadband performance for gain and impedance.
 P. V. Bijumon, A. P. Freundorfer, M. Sayer and Y. M. M. Antar, "On-Chip Silicon Integrated Cylindrical Dielectric Resonator Antenna for Millimeter Wave Applications," 2007 International Symposium on Signals, Systems and Electronics, Montreal, QC, 2007, pp. 489-492, doi: 10.1109/ISSSE.2007.4294520.