Ylr. Lee et al., Dipole and tripole metallodielectric photonic bandgap (MPBG) structures for microwave filter and antenna applications, IEE P-OPTO, 147(6), 2000, pp. 395-400
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.