Dissipative properties of a round-the-world decameter-range echo

Experimental data on the attenuation of multiple round-the-world signals is analyzed on the basis of a conical Legendre wave representation with a complex phase as a model for the propagation of decameter waves on ultralong paths. An adequate analysis of the role of focusing makes it possible to establish a correspondence between different sets of experimental data on the amplitude of round-the-world signals and estimates based on ionospheric models.