Abstract: To obtain the RCS of dipole-array antennas, the system of electric field integral equations is turned into a linear algebra system whose coefficient matrix is a symmetric block Toeplitz complex matrix by using Calerkin method with pulse basis functions. The linear algebra system is solved by a combination of the preconditioned conjugate gradient method (PCG) with the fast Fourier transform (FFT), where T. Chan optimal circulant preconditioner is used. The above method reduces the need for computer memory, speeds the iteration and enhances the convergence.

Key words: preconditioned conjugate gradient method, dipole-array antenna, radar cross-section