Dipole and tripole metallodielectric photonic bandgap (MPBG) structures for microwave filter and antenna applications

A photonic band gap structure made from periodic arrays of conducting dipol es and tripoles on a dielectric is presented. Using the proposed structures , several example devices have been demonstrated for microstrip resonators and filters as well as patch antennas. Measured and predicted frequency res ponses of a microstrip line using a dual dipole metallodielectric photonic bandgap (MPBG) structure show a 40% band width centred at 10 GHz. A planar microstrip resonator using a dipole MPBG shows a slower wave performance an d a higher Q factor when compared with the conventional half-wavelength res onator. Three patch antenna designs on different dielectric constant substr ates using a tripole MBPG produce better return loss, higher boresight gain s (up to 3 dB) and smoother radiation patterns as a result of surface wave suppression.