Since photonic band gap structures (PBG) have been built for the millimetre
frequencies scientists have tried to use such PBG materials to solve their
electromagnetic problems concerning antennas or waveguiding applications.
The finite difference time domain (FDTD) method is an efficient tool for el
ectromagnetic analysis and can be used to study PBG structures. In this pap
er we present different electromagnetic analyses using FDTD to study PBG ma
terials.