INFLUENCE OF A LUMPED LOAD ON EM SCATTERING OF A RECEIVING WIRE ANTENNA

Electromagnetic (EM) scattering of a receiving antenna can be affected by changing the impedance of a lumped load connected to its accessible ports. The EM reciprocity theorem of the time‐convolution type is applied to show that the change in such antenna's EM scattering characteristics is intimately related to the corresponding transmitting state, namely, to antenna's (impulse‐excited) radiation characteristics. This chapter evaluates the change of EM scattering of a wire antenna due to the change in its lumped load. At first, it employs the reciprocity relation and finds the impact of a variable load from the relevant radiated far‐field amplitude and the corresponding voltage difference across the load. Secondly, for validation purposes, the change of EM scattering characteristics is evaluated directly. The point of departure for the EM reciprocity analysis is the single‐port time domain counterpart of the reciprocity relation that is written in terms of far‐field amplitudes.