Аннотация:The suggested approach allowed us to derive analytical expressions for modeling the shape of solid-echo signal and its time evolution for a system of three-spin groups with arbitrary constants of dipole–dipole interaction (DDI) in solids. Our method is based on the use of symmetry operations for spin exchange and spin flipping along the axis of initial polarization. Most useful seem to be the results on the shape solid echo signals. Upon comparison with experiment, our results may in turn be helpful in estimating a ratio of DDI constants and elucidating the mutual orientation of three-spin groups in a solid under study.