Polarizabilities and fundamental bounds on antennas

Fundamental bounds on single-port antennas and on array antennas have been shown to depend on the electric and magnetic polarizability tensors. We show four such cases and compare how the polarizabilities enter into the bounds. One of the critical items in using these bounds is the determination of the polarizabilities. We here review methods to obtain the polarizabilities, and discuss some of their features. An illustration of one of the methods is also given.