Aperture-coupled patch antenna on UC-PBG substrate

• Published in: IEEE transactions on microwave theory and techniques Vol. 47; no. 11; pp. 2123 - 2130
• Main Authors: Coccioli, R., Fei-Ran Yang, Kuang-Ping Ma, Itoh, T.
• Format: Journal Article
• Language: English
• Published: IEEE 01.11.1999
• Subjects: Antenna measurements; Antennas; Computation; Dielectric constant; Dielectric losses; Dielectric measurements; Dielectric substrates; Directive antennas; Dispersions; Frequency; Gain; Gain measurement; Microwaves; Noise levels; Optical losses; Patch antennas; Photonic band gap
• ISSN: 0018-9480; 1557-9670
• DOI: 10.1109/22.798008

The recently developed uniplanar compact photonic bandgap (UC-PBG) substrate is successfully used to reduce surface-wave losses for an aperture-coupled fed patch antenna on a thick high dielectric-constant substrate. The surface-wave dispersion diagram of the UC-PBG substrate has been numerically computed for two different substrate thickness (25 and 50 mil) and found to have a complete stopband in the frequency range of 10.9-13.5 and 11.4-12.8 GHz, respectively. The thicker substrate is then used to enhance broadside gain of a patch antenna working in the stopband at 12 GHz. Computed results and measured data show that, due to effective surface-wave suppression, the antenna mounted on the UC-PBG substrate has over 3-dB higher gain in the broadside direction than the same antenna etched on a grounded dielectric slab with same thickness and dielectric constant. Cross-polarization level remains 13 dB down the co-polar component level for both E- and H-planes.