A method for calculating a velocity vp(f, Topt) of a spatially aliased wave that propagates along a cable includes tensioning the cable, wherein plural sensors are distributed along the cable; measuring with the plural sensors a parameter that is associated with vibrations that propagate along the cable; calculating a phase velocity vp(f) of the spatially aliased wave that propagates along the cable, as a function of a time frequency fin a spatial-temporal frequency domain FK; calculating a model-based velocity vp(f, T) of the spatially aliased wave as a function of the time frequency f and a tension T in the cable; and calculating the velocity vp(f, Topt) of the spatially aliased wave using a model-guided regression, which is based on the phase velocity vp(f) and the model-based velocity vp(f, T). The velocity vp(f, Topt) is a function of the temporal frequency f.