ANALYSIS OF A GRID DIPOLE ARRAY PLACED INSIDE A WAVEGUIDE CAVITY WITH A RECTANGULAR COUPLING APERTURE

✍ Scribed by G. E. STRATAKOS; N. K. UZUNOGLU

• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 275 KB
• Volume: 10
• Category: Article
• ISSN: 0894-3370
• DOI: 10.1002/(sici)1099-1204(199701)10:1<35::aid-jnm255>3.0.co;2-l

✦ Synopsis

The circuit and coupling properties of a dipole grid array placed inside a rectangular cross-section waveguide are analysed when also a rectangular aperture is used to couple the resonator energy into a semi-infinite waveguide. A Green function approach is employed to determine the current distribution on the dipole elements by solving an integral equation and taking into account the boundary conditions on the rectangular cavity walls. Both mutual and self-impedance terms are calculated for the dipole grid array, and the effects of the rectangular coupling aperture are also examined. To the authors' knowledge this type of structure has not been analysed elsewhere, while several authors have studied the scattering properties of rectangular shaped iris structures in rectangular waveguides under dominant mode excitation. 2,[11][12][13] In the following a two-step procedure is applied to analyse the geometry given in Figure 1. To this end an integral equation approach is used based on a Green function approach. In the first place the Green function is determined for the waveguide cavity with a coupling iris into a semi-infinite waveguide. Then a system of Pocklington type integral equations is written for the unknown strip dipole currents. This system of integral equations is solved by applying a method Figure 1. Rectangular waveguide cavity resonator incorporating a grid array