We consider the electromagnetic field generated by passing an impulsive current of the form of a delta function δ(t) through a vertical antenna placed on a dielectric ground. The problem is formulated in oper-ational form, and the Hertzian potential ∏ is expressed as an integral over a Bessel function. This operational solution is then inverted, and the Hertzian potential ∏(r,z,t) is expressed in terms of finite complex integrals over a fixed range. The integrals for ∏ were evaluated on the electronic computer of the Weizmann Institute, and the results for the case of a dielectric constant ε = 9 are shown in Figure 2. The field in the air starts with a finite value at the time of arrival of the wave front, and then increases in a monotone fashion toward the steady state value.
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