Compact resonant bandpass filter based on PBG structure

A new resonant bandpass filter based on a photonic band gap (PBG) structure is designed and optimised. The finite-difference time-domain method is applied to characterise the proposed filter. The filter is much easier to fabricate, more compact and simpler to design than the conventional parallel-coupled line filter, has wide stopband and steep and deep upper bandstop. The filter length is about one guiding wavelength (λe). A semiconductor-based structure is realised using microelectronics technology and good agreement between the experimental and simulation results has been achieved.