Wire structures are made of linear PEC elements. These may consist of actual physical wires such as a dipole or loop antenna or a wireframe representation of a surface or solid object. In a wire structure, the unknown electric currents are one-dimensional. The integral equation is derived by forcing the tangential component of the electric field to vanish on the surface of the wire. This leads to the following simpler integral equation:
:<math>\mathbf{ \hat{I} \cdot E^i } - jk_0 Z_0 \int_C \left( G_A \mathbf{(r|r')} I(l') \mathbf{ \hat{l} \cdot \hat{l}' }+ \frac{1}{{k_0}^2} \frac{\partial G_A}{\partial l} \frac{\partial I}{\partial l'} \right) \, dl' = 0</math><!--[[File:14_pocklingtons_tn.gif]]-->
where [[File:15_pocklingtons_tn.gif]] G<sub>A</sub> is the free space Greenâs function, I(l) is the unknown linear current in the wire and C is the contour of the wire. and [[File:17_pocklingtons_tn.gif]] <math>\hat{l}'</math> are the unit vectors along the wire contour. Note that [[File:15_pocklingtons_tn.gif]] G<sub>A</sub> has a singularity when r = râ, which must be either removed or avoided as will be explained later.
=== Discretization Of Wire Structures ===