By Ian Darney
At its half-wave frequency, a dipole antenna provides a load on the RF transmitter which is purely resistive; the Radiation Resistance. At other frequencies the antenna behaves as a series LCR circuit.
If a voltage source is located at the centre of a long conductor, then this assembly will behave in essentially the same way. The current flowing in the conductor is a measure of the electromagnetic energy delivered to the environment. A circuit model is developed which accurately simulates the frequency response of such an assembly. It is entirely possible to extend the use of the technique of circuit modelling to analyse radiated interference.