  Frequency and transmission spectrum of two-dimensional array of metallic rods
is investigated numerically. Based on the recent analysis of the band structure
of two-dimensional photonic crystal with dielectric rods [P. Marko\v{s}, Phys.
Rev. A 92 043814 (2015)] we identify two types of bands in the frequency
spectrum: Bragg (P) bands resulting from a periodicity and Fano (F) bands which
arise from Fano resonances associated with each of the cylinders within the
periodic structure. It is shown that the existence of Fano band in a certain
frequency range is manifested by a Fano resonance in the transmittance. In
particular, we re-examine the symmetry properties of the H- polarized band
structure in the frequency range where the spectrum consists of the localized
modes associated with the single scatterer resonances and we explore process of
formation of Fano bands by identifying individual terms in the expansion of the
LCAO states. We demonstrate how the interplay between the two scattering
mechanisms affects properties of the resulting band structure when the radius
of cylinders is increased. We show that a different character of both kinds of
bands is reflected in the spatial distribution of the magnetic field which
displays patterns corresponding to the corresponding irreducible symmetry
representations.
