RADIATION FROM ONE-DIMENSIONAL DIELECTRIC LEAKY-WAVE ANTENNAS

Dielectric leaky-wave antennas consist of multiple dielectric layers a bove a ground plane, along with a simple source such as an infinite li ne current in the one-dimensional case. The layers act as a guiding st ructure for one or more leaky waves, which are responsible for produci ng a narrow-beam radiation pattern. Depending on the beam angle, the l eaky waves may extend for a considerable distance from the source, and thus experience truncation effects due to a finite-size substrate. On e of the purposes of the present investigation is to study efficient m ethods for calculating the patterns under such conditions. The chirp z -transform (CZT) is shown to be very efficient for this. Simple approx imate formulas for calculating the radiation pattern are also investig ated. In addition, a study is also made of the different contributions to the total aperture field, including the leaky-wave field, the spac e-wave field, and the surface-wave field.