The biconjugate gradient-fast Fourier transform (BCG-FFT) method is a very
efficient and useful technique to analyze microstrip antennas and arrays. I
n order to increase the efficiency of the BCG-FFT method by reducing the nu
mber of iterations a multilevel BCG-FFT method is constructed using the ide
a of multigrid methods. The analysis of microstrip antennas and arrays illu
strates that the multilevel BCG-FFT method has good accuracy and is much fa
ster than the BCG-FFT method. (C) 2000 John Wiley & Sons, Inc.