magnetic field. Inf. Control. 9(1), 1-22 (1966) 12. G.T. Di Francia, Degrees of freedom of an image. JOSA 59(7), 799-804 (1969) 13. F. Gori, G. Guattari, Shannon number and degrees of freedom of an image. Opt. Commun. 7(2), 163-165 (1973) 14. C.W. Helstrom, Resolvable degrees of freedom in observation of a coherent object. JOSA 67(6), 833-838 (1977) 15. T. Jannson, Shannon number of an image and structural information capacity in volume holography. Optica Acta Int. J. Optics 27(9), 1335-1344 (1980) 16. R. Piestun, D.A. Miller, Electromagnetic degrees of freedom of an optical system. JOSA A 17(5), 892-902 (2000) 17. M. Born, E. Wolf, Principles of Optics: Electromagnetic Theory of Propagation, Interference and Diffraction of Light (Elsevier, Amsterdam, 2013) 18. L. Mandel, E. Wolf, Optical Coherence and Quantum Optics (Cambridge University Press, Cambridge, 1995) 19. M.D. Migliore, The world beneath the physical layer: an introduction to the deep physical layer. IEEE Access 9, 77106-77126 (2021) 20. O.M. Bucci, G. Franceschetti, On the degrees of freedom of scattered fields. IEEE Trans. Antennas Propag. 37(7), 918-926 (1989) 21. O. Bucci, G. Franceschetti, On the spatial bandwidth of scattered fields. IEEE Trans. Antennas Propag. 35(12), 1445-1455 (1987) 22. O.M. Bucci, C. Gennarelli, C. Savarese, Representation of electromagnetic fields over arbitrary surfaces by a finite and nonredundant number of samples. IEEE Trans. Antennas Propag. 46(3), 351-359 (1998) 23. O.M. Bucci, C. Gennarelli, C. Savarese, Fast and accurate near-field-far-field transformation by sampling interpolation of plane-polar measurements. IEEE Trans. Antennas Propag. 39(1), 48-55 (1991) 24. J. Bolomey, O.M. Bucci, L. Casavola, G. D'Elia, M.D. Migliore, A. Ziyyat, 'Reduction of truncation error in near-field measurements of antennas of base-station mobile communication systems. IEEE Trans. Antennas Propag. 52(2), 593-602 (2004) 25. J.W. Wallace, M.A. Jensen, Intrinsic capacity of the mimo wireless channel, in Proceedings IEEE 56th Vehicular Tech