Spatial response of a miniature field probe in an arbitrary electric field

A miniature electromagnetic field probe using a 0.6-mm linear dipole antenna has been developed. The probe response in a spatially varying electric field is studied. Based on the Nyquist sampling theorem, the spatial sampling frequency at which an electric field should be measured to obtain good reconstruction is established. It is shown that for an undistorted reconstruction of the electric field, the field itself should be sampled at a frequency higher than twice its spatial frequency component and the highest frequency component of the antenna transmitting current. If this criterion is satisfied, then the relationship between the electric field and the antenna voltage response shows that accurate reconstruction of the field is possible with a good knowledge of the antenna transmitting current. Theoretical findings are compared with numerical results for the voltage response obtained with the method of moments. Only one-dimensional fields are considered, but the methodology presented can be applied to general three-dimensional fields