Upper Bound on Cell Size for Moment-Method Solutions

When pulse functions are used in moment-method solutions, failure to allow for variation of the field within each cell limits the maximum usable electrical size of the cells. Appreciable error is expected for |k| l >or= 2 in one or two dimensions and |k| l >or= /spl radic/6 in the three-dimensional problem where l is the side of a cell and k is the propagation constant in the material.