Simulation and derivation of typical photonic bandgap structure’s design parameters using curve fitting method

Photonic bandgap (PBG) structure are periodic structures in which the propagation of energy in certain bands of frequencies is prohibited. PBG structures have been considered as an alternative to solve problems in microwave-circuit applications. On possible way to reject out-of-band frequencies is to use a PBG structure. In this paper, we use a new PBG structure that requires only partial etching of the ground plane, which is compatible with monolithic circuit technology. Besides, also, the equations for the low and high frequencies are obtained in the proposed photonic band gap (PBG) structure. By means of those equations, we can design proposed PBG structure for the certain bandwidth and obtain the desired radius of etched circular(r). Finally, transmission parameter (S12) is obtained versus the radius of etched circular and designed the PBG filter for S12 less than minus 10 and attained optimum radius. Also, the used method for equations calculation has been curve fitting.