Study On Defected Ground Structure Model And Applications Of Microwave Integrated Circuits

Early in the 21th century, J.I.Park of Korea Scholar presented a novel structure called Defected Ground Structure (DGS), which has bandgap characteristics and slow-wave effect, just like photonic bandgap structure. It may apply in every domain of microwave plane circuits and greatly improve performance of microwave integrated circuits(MIC), so it becomes a research hotspot of MIC design domain. Currently, research, development and application on microwave circuit ground plane is a very important concept renovation and technology innovation in microwave circuit design development course.According to practice demand of constructing a novel microwave circuit, under support of several scientific research projects, the author has done much research on model analysis method and transmission characteristic of DGS. The author has also constructed a novel DGS structure and carried on detailed analysis on its equivalent circuit. Based on model analysis, simulation has been done on periodic and nonperiodic DGS structure, their frequency characteristic and their applications in microwave circuit have been presented. In the end, the author introduces DGS's applications in microwave circuit in detail, has designed high stages lowpass filter of DGS structure and Power Divider using asymmetric spiral DGS structure. DGS structure has also been used in microwave power amplifier design, mainly in high order harmonic suppression in order to improve performance index of microwave power amplifier.In a word, the paper has presented theory base and circuit design examples to novel Radar systems and MIC with high performance, small size, low power loss, and novel periodic structure (EBG and DGS).