Greens tensors in the frequency domain

The electromagnetic Green s tensors Ge, G// are introduced as the fields of an elementary electric source (Zhdanov, 1988 Felsen and Marcuvitz, 1994). They satisfy the Maxwell s equations 

Equations (8.123) suggest that in a homogeneous domain G and Gh satisfy the Helmholtz equations 

The importance of Green s functions in electromagnetic theory is dictated by the following considerations. According to the basic property of -function (8.124), any source, j (r ), can be represented as a sum of elementary current sources  

---