Equivalent network of transverse dipoles in inset dielectric guide: application to linear arrays

The inset dielectric guide (IDG) is an alternative to the image line, retaining most if its advantages without its main disadvantages. In particular, IDG makes it possible to realize low-cost leaky wave antennas with very pure polarization properties by laying thin metal strips (dipoles) on the air-dielectric interface. The scattering properties of thin metal strips are analyzed by means of a Ritz-Galerkin variational approach, taking into proper account the edge singularities. A variational expression for the equivalent circuit of the radiating dipole is derived, and this information is applied to the design of a tapered linear array by network methods. The array was built and tested, and it showed excellent performance