A CAD tool for interference rejection of a microwave circuit making use of resonance of the circuit packaging

Microwave circuits, especially amplifiers, are usually wideband devices. Sometimes it is necessary to design a circuit to specifically reject narrow band interferences. Dielectric resonator is one way, another way is to use the resonance of the circuit packaging. The circuit packaging resonance is normally considered a nuisance. In this paper the circuit packaging is considered as a component of the circuit instead. The package dimensions are then entered in an iterative MoM algorithm to find the optimum packaging size that can bring the box resonances to the proper locations along the circuit frequency band. A number of examples are given.<>