Coupling of External Electromagnetic Fields to Transmission Lines

Regarding the development of the field-to- cable coupling model, the two-wire line is presented first. The differential-mode and common- mode current by the method of images are discussed, as well as the wire over a ground plane and dissipative losses. With plane-wave excitation, electrical field parallel to the termination is reviewed. Then electrical field parallel to the conductors and to the plane of the wire over a ground plane are addressed. Time domain responses are also covered. The exact and approximate methods of a line excited by a small loop and short dipole are reviewed. Illustrative numerical examples of both are given. Shielded cables are discussed at length. Sheath current distributions and load current spectrum are presented. The shielding effectiveness and transfer impedance's of a number of shielded cables are illustrated. The appendices cover topics including the derivation of coupled first-order equations from field theory. The review of transmission-line theory includes lines driven at one end, midsection and at both ends. Conditions corresponding to a line with distributed sources along the conductors are given.