Ali E. Atia

Narrow-Bandpass Waveguide Filters

A procedure is described whereby narrow-bandpass waveguide filters having ripple in both the passbands and stopbands can be synthesized in the form of coupled waveguide cavities. Orthogonal modes in square or circular waveguides are employed to enable negative coupling elements to be realized. As a consequence, very compact filters can be constructed. Experimental results on an 8-cavity orthogonal-mode narrow-bandpass filter are shown to agree well with theory.

Narrow-band multiple-coupled cavity synthesis

A synthesis procedure of identical narrow-band high-Q cavities is presented. The procedure handles multiple couplings in a noncascaded form by synthesizing coupling impedances in one step. Necessary and sufficient conditions for realizability of singly and doubly terminated networks are obtained. An example of a sixth-order elliptic function waveguide filter is included.