A highly effective preconditioner for MoM analysis of large slot arrays

A highly effective preconditioner is presented to solve the system of equations obtained from the application of the moment methods to slotted waveguide array antenna problems. This preconditioner accounts for the near field (expansion function - testing function) interactions for a given basis function on a slot. When conjugate gradient method is employed to solve the preconditioned system equation, the convergence can be greatly accelerated. Numerical results show that the proposed preconditioner can improve the convergence of an iterative solution by an order of magnitude for large slot arrays.