  We investigate the Cherenkov radiation by a charge uniformly moving inside a
dielectric cylindrical channel in a homogeneous medium. The expressions for the
Fourier components of the electric and magnetic fields are derived by using the
electromagnetic field Green tensor. The spectral distribution of the Cherenkov
radiation intensity in the exterior medium is studied for the general case of
frequency dispersion of the interior and exterior dielectric functions. It is
shown that, under certain conditions on the dielectric permittivities, strong
narrow peaks appear in the spectral distribution. The spectral locations of
those peaks are specified and their heights and widths are estimated
analytically on the base of the dispersion equation for the electromagnetic
eigenmodes of the cylinder.
