Abstract:
Filters are used for eliminating some unwanted frequencies in electronic signals. It is possible to design a filter with lumped elements at low frequencies. But increasing frequency will introduce some problems. Since serial production of capacitors and inductors at low values and small tolerances is effortful, it is difficult to design a high frequency sharp filter with commercially available lumped elements. Consequently filters with distributed elements in microwave frequencies have become functional. Therefore this report concentrates on design of microwave filters using Microstrip structures as distributed elements.
Another trend in recent years has been the development of design and simulation software. Comparison of manual with computerized solutions and investigation of advantages of iterative computerized solutions are also considered in the report.
Finally the report analyzed the results obtained from measurements of hardware fabricated to apply two filter tuning technologies (varactor diodes and BST capacitors).