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Spherical-Wave Characterization of Interior and Exterior Sources



David A. Hill


This paper presents the theoretical basis for spherical, near-field scanning in the general case where radiating sources exist both inside and outside the measurement region. The fields are expanded in terms of outgoing spherical waves (due to interior sources) and standing spherical waves (dure to exterior sources). Additional information is required to solve for the increased number of unknowns, and results for the spherical-wave coefficients are derived in terms of the tangential electric and magnetic fields on the surface of a sphere. The special case of an electrically small emitter is examined in detail, and several formulations are presented for the equivalent electric and magnetic dipole moments.
Proceedings Title
Proc., IEEE Intl. Electromagnetic Compatibility (EMC) Symposium
Conference Dates
August 24-28, 1998
Conference Location
Denver, CO


electric dipole, magnetic dipole, near-field measurement, spherical scanning, spherical wave, test volume


Hill, D. (1998), Spherical-Wave Characterization of Interior and Exterior Sources, Proc., IEEE Intl. Electromagnetic Compatibility (EMC) Symposium, Denver, CO (Accessed June 25, 2024)


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Created August 1, 1998, Updated February 19, 2017