doi:10.1029/2018RS006692engAyuso, NataliaCuchí, José AntonioLera, FranciscoVillarroel, José LuisA Computational Channel Model for Magnetic Induction-Based Subsurface ApplicationsART-2019-114073There are many underground applications based on magnetic fields generated by an oscillating magnetic source. For them, a magnetic dipole in a three-layered region with upper semi-infinite air layer can be a convenient idealization used for their planning, development, and operation. Solutions are in the form of the well-known Sommerfeld integral expressions that can be evaluated by numerical methods. A set of field expressions to be numerically evaluated by an efficient algorithm are not collected comprehensively yet, or at least in a directly usable form. In this paper, the explicit magnetic field solutions for the vertical magnetic dipole and the horizontal magnetic dipole for a general source-observer location are derived from the Hertz vector. They can be properly combined to model the problem of a tilted magnetic dipole source for horizontally or inclined stratified media. As a result, a complete set of integral equations of the Sommerfeld type valid from the near zone to the far zone are formulated. A method for numerical evaluation of the field expressions for high accurate computations is described. The numerical results are validated using the finite element method for all the possible source-receiver configurations and three well-spanned frequencies of typical subsurface applications. Both numerical solutions agree according to the normalized root-mean-square error-based fit metric. Numerical results for two cases of study are presented to see its usefulness for subsurface applications. A MATLAB implementation of the mathematical description outlined in this paper and the proposed evaluation method is freely available for download.2019http://zaguan.unizar.es/record/8822910.1029/2018RS006692http://zaguan.unizar.es/record/88229oai:zaguan.unizar.es:88229info:eu-repo/grantAgreement/ES/MINECO-AEI-FEDER/DPI2016-76676-Rinfo:eu-repo/grantAgreement/ES/DGA/T45-17Rinfo:eu-repo/grantAgreement/ES/MINECO/DPI2016-76676-RRADIO SCIENCE 54, 9 (2019), 822-838All rights reservedhttp://www.europeana.eu/rights/rr-f/info:eu-repo/semantics/openAccess