Uniplanar Passive Recursive Microwave Filter with Microstrip Radial-Line Power Dividers-Combiners

The use of microstrip radial-line dividers-combiners is a new approach in the field of microvave recursive passive filter synthesis. The filter design consists firstly of an electromagnetic theoretical analysis of microstrip radial-line dividers-combiners and secondly of its appropriate use to achieve a recursive filter transfer function. A good agreement is finally shown between theoretical and experimental results for a 2.8 GHz frequency bandwidth bandpass filter centred at 12 GHz and illustrates the validity of this synthesis.