Therefore it considers the computational domain as a mesh of transmission lines, interconnected at nodes.

These are also known as body fitted grids and works on the principle of mapping the flow domain onto computational domain with simple shape.

And then the BKM solution at any location of computational domain can be evaluated by the formulation (4).

The computational domain is simply the physical region over which the simulation will be performed.

The E and H fields are determined at every point in space within that computational domain.

The material of each cell within the computational domain must be specified.

Once the computational domain and the grid materials are established, a source is specified.

If the field values at some distance are desired, it is likely that this distance will force the computational domain to be excessively large.

Clearly, these have to be functions, taking inputs from some computational domain and returning outputs in some (possibly different) domain.

Green's function depends on the shape of the computational domain, therefore it is usually not known.