A mathematical approach is presented that is based on coupled-mode theory (CMT); it is extended to infinite perfect photonic structures and combined with the supercell method for analysis of infinite photonic crystals with introduced point (0D) and linear (1D) defects. This approach shows a strong advantage over most existing techniques in regards to time and consumption of resources, and thus allows one to quickly analyze operational characteristics of different photonic devices [photonic crystal fibers (PCFs), phased arrays of VCSELs, etc.] over a wide range of physical parameters. (C) 2009 Optical Society of America