What field is associated with the energy stored in an antenna?

The energy stored in an antenna is primarily associated with the concept of induction. Antennas operate on principles related to electromagnetic waves, where energy is radiated into space and also received from external sources. When an alternating current flows through an antenna, it generates a time-varying magnetic field around it, which induces an electric field. This interaction is the fundamental principle of induction, which describes how a change in magnetic field can produce an electric current in a conductor.

In the context of antennas, inductive effects are crucial as they help in determining the impedance and efficiency of the antenna in transmitting and receiving signals. This is important in wireless communication, where antennas are relied upon to effectively couple electromagnetic energy with the air or another medium.

The other concepts listed, while related to various electrical phenomena, do not directly correlate with the principle of energy storage in antennas. Radiation pertains to the emission of energy; conduction involves the flow of electric current through materials; and capacitance relates to the storage of electrical energy in an electric field. However, the storage of energy connected to the operation of an antenna fundamentally hinges on inductive principles.