  The weak localization correction to the conductivity in coupled double layer
structures is studied both experimentally and theoretically. Statistics of
closed paths has been obtained from the analysis of magnetic field and
temperature dependencies of negative magnetoresistance for magnetic field
perpendicular and parallel to the structure plane. The comparison of
experimental data with results of computer simulation of carrier motion over
two 2D layers with scattering shows that inter-layers transitions play decisive
role in the weak localization.
