ABSTRACT
Before going into NEA methods, let us look at Maxwell’s equations, which are the fundamentals of electromagnetics. They are stated in the time domain as
∇ × = − ∂ ∂E r
B r ( , )
( , ) t
t t
(5.1)
∇ × = ∂ ∂ +H r
D r J r( , )
( , ) ( , )t
t t
t
(5.2)
∇⋅ =D r r( , ) ( , )t tρ (5.3)
∇⋅ =B r( , )t 0 (5.4)
where E(r, t) is the electric eld H(r, t) is the magnetic eld D(r, t) is the electric-ux density B(r, t) is the magnetic-ux density J(r, t) is the conduction current density ρ(r, t) are the volume charge density, each at space point r and at time t
Equation 5.1 represents Faraday’s law, and Equation 5.2 represents Ampere’s law. Equations 5.3 and 5.4 represent Gauss’s laws for electric and magnetic elds, respectively.
