Evaluation of edge effects in slot arrays using the geometrical theory of diffraction
Abstract
The geometric theory of diffraction is applied to evaluate the coupling coefficient (CC) associated with the design of a waveguidefed longitudinal shunt slot arrays. The CC is proportional to the reaction integral between the field of a slot and the equivalent current distribution of another slot. Using an approximate form of the Green function for the wedge, it is shown that the edgediffraction field due to each slot is practically equal to the field of a suitable 'mirror image' of such slot. In this way the actual CC can be decomposed into a sum of CCs between slots on an infinite ground plane. The latter can be evaluated very efficiently so that inclusion of edge effects does not slow down the design procedure. The same aproach also allows the computation of the relation between the selfadmittance with and without the edge. Test cases show that the overall error of this approximation is comparable to the error due to mechanical tolerances.
 Publication:

IEEE Transactions on Antennas and Propagation
 Pub Date:
 March 1989
 DOI:
 10.1109/8.18737
 Bibcode:
 1989ITAP...37..392M
 Keywords:

 Antenna Arrays;
 Electromagnetic Coupling;
 Geometrical Theory Of Diffraction;
 Slot Antennas;
 Fourier Series;
 Green'S Functions;
 Standing Wave Ratios;
 Electronics and Electrical Engineering