In most modern textbooks on antennas, it is stated that receiving antennas scatter as much as they absorb under matched-load conditions. This is incorrect, as was shown 50 years ago. The reason for this discrepancy is an apparently incorrect use of the equivalent circuits. In this tutorial paper, a simple example of a two-element Yagi antenna and a test dipole in the far field is analyzed for transmission, reception, and scattering, through the use of the symmetric impedance matrix. It is shown that the correct equivalent circuit for the scattering case is more complicated, owing to the existence of more sources than in the transmitting case. Through a numerical example, it is also shown that the scattered power may be larger, equal to, or smaller than the absorbed power.
[1]
C. G. Montgomery,et al.
Principles of Microwave Circuits
,
1965
.
[2]
R. Green,et al.
Scattering from conjugate-matched antennas
,
1966
.
[3]
Donald W. Dearholt,et al.
Electromagnetic Wave Propagation
,
2020,
Wireless Internet of Things.
[4]
Constantine A. Balanis,et al.
Antenna Theory: Analysis and Design
,
1982
.
[5]
A. W. Love.
Comment on the equivalent circuit of a receiving antenna
,
2002
.
[6]
R. E. Collin,et al.
Limitations of the Thevenin and Norton equivalent circuits for a receiving antenna
,
2003
.
[7]
Rodney G. Vaughan,et al.
Channels, Propagation and Antennas for Mobile Communications
,
2003
.