FAST AND ACCURATE ANALYSIS OF WAVE-GUIDE FILTERS BY THE COUPLED-INTEGRAL-EQUATIONS TECHNIQUE

The coupled-integral-equations technique (CIET) is successfully applie d to accurately determine the frequency response of waveguide filters in a single step, A four-resonator H-plane filter is analyzed by the m ode-matching technique (MMT) and the CIET for comparison and results i n a reduction of central-processing-unit (CPU) time of the order of 40 0, A set of CIE's for the tangential electric fields at the apertures of the discontinuities are derived and solved by the moment method, Ba sis functions, which include the edge conditions at each of the discon tinuities, are used to achieve numerical efficiency, It is shown that 1-4 basis functions, which include the edge conditions, are sufficient over a broad range of frequencies.:The inclusion of the edge conditio ns in the basis functions is shown to have a dramatic effect on the co nvergence of the CIET, especially for narrow-band filters.