Multilayer Planar Resonators with Superconductive Patch on PBG Substrate

Abstract

The rectangular discretized multilayer microstrip resonators, analyzed using the full wave TTL | Transverse Transmission Line method in the spectral domain, jointly with the moment method are presented. The homogenization theory is used to calculate the equivalent permittivity for the s and p polarizations of the structure composed of PBG (Photonic Band Gap) material. Numerical results of the resonance frequency for the rectangular multilayer, on isotropic and anisotropic PBG material substrate resonators are presented. DOI: 10.2529/PIERS060908155123 The microstrip antennas have received more attention due to the characteristics and advantages comparison with the conventional antennas. These antennas present small volume, reduced weight, planar conflguration, compatibility with integrated hybrid circuits and the possibility of acting with dual frequency (1). They can be used in several systems, such as: radars, wireless, mobile telephony and communication by satellites. However, they present disadvantages with relationship to the narrow band, losses due to the low gain and losses by irradiation due to the surface waves. These disadvantages can be eliminated, by using a screening to avoid losses by irradiation (2) and antennas with PBG substrate (Photonic Bandgap) (3). Some techniques to increase the band width are used among the: thicker substrate (4), multilayer antennas or stacked patches (5,6). Antennas with dielectric multilayer have advantages, such as, the ∞exibility in the operation frequency band, a smaller physical size, etc. The PBG materials are a new type of periodic substrates structure in which the propagation in certain bands of frequencies is prohibited (7). In this work the rectangular multilayer resonators on PBG substrate are analyzed, as illustrated in the Fig. 1.