RCS calculations of resonant dipole antennas with arbitrary loads based on the equivalent circuit method

Antennas receive the power from free space and transmit it to the loads. In this process, antennas are like power supplies with impedance. So the equivalent circuit method can be used to study receiver antennas. From the equivalent receiver circuit of dipole antennas, the relationship between dipole antennas as scatters and as radiators is found. The radar cross-section (RCS) expressions of resonant dipole antennas with arbitrary loads are obtained from the relationship. These RCS expressions are not only used to study the scattering properties of dipole antennas, but also to calculate the RCS values of an ideal dipole with arbitrary loads, e.g. short, open or match circuit. The results calculated are consistent with the ones simulated by HFSS.