  We study analytically and numerically field/intensity correlations in wave
transport through volume-disordered waveguide. The obtained channel and spacial
correlations deviate from those found in framework of
Dorokhov-Mello-Pereyra-Kumar (DMPK) formalism, that we relate to
inapplicability of equivalent channel approximation in DMPK. We show that this
can be remedied by introducing boundary correction -- an escape function which
depends on the waveguide geometry -- that describes wave transport near a
boundary between random medium and free space. We obtain the expressions for
field/intensity channel and spacial correlation functions which agree with the
numerics and are consistent with the perturbative expressions in slab geometry
as well as experiments conducted in Q1D.

Mesoscale and Nanoscale Physics;Disordered Systems and Neural Networks