Traveling wave antenna with non-dissipative loading

An approximate theory for a lumped impedance loaded traveling wave linear antenna is presented. The approximate current distribution on the antenna is determined in terms of its dimensions and the impedance and position of the double loading. From this result, the optimum impedance to yield an outward traveling wave of current is determined. Significantly, it is indicated that a purely reactive loading may be utilized if its position is properly chosen. Expressions for the input impedance and radiation fields corresponding to the traveling wave of current are presented. Numerical results for an antenna of particular dimensions are included, and compared where appropriate with available experimental data.