Design and Optimization of Microstrip Interdigital Bandpass Filters with Impedance Matching

摘要

A least square based method is developed for the design and optimization of mi-crostrip interdigital bandpass filters. The N coupled transmission line theory is employed to take into account the couplings among adjacent and nonadjacent conducting strips. The algorithm also incorporates the load and source impedance matching. The minimization of error function determines the length, width and spacing of strips. The performance of the optimized filter design perfectly agrees with the microwave simulation softwares.