공통 결함접지구조를 이용한 방향성 결합기의 설계

다국어 초록 (Multilingual Abstract)

A new directional coupler structure for microwave applications is described using common a defected ground structure (DGS) in this work. The common DGS (CDGS) structure is realized on the common ground plane which is centered of double-sided substrate. So it operates as a DGS for both microstrip lines which exist with a back-to-back structure to each other. The coupling phenomenon happens vertically between top and bottom microstrip lines through the CDGS, while the signal couples to the next coupled line planarly in the conventional directional couplers. As an example, a 15㏈ directional coupler at 1.5㎓ is designed and measured using the CDGS structure. The proposed directional coupler has the reduced size by 57% compared to the conventional design while the performances are preserved. The measured transmission loss and coupling coefficient of the fabricated coupler are 0.5㏈ and 15.7㏈, respectively, which show excellent performances as a directional coupler. The agreement between the simulated and measured S-parameters is very reliable.

참고문헌 (Reference)

1 임종식, "비대칭 나선형 결함접지구조를 이용한 마이크로파 증폭기 설계" 한국정보기술학회 8 (8): 71-79, 2010

2 I. Rumsey, "Photonic Bandgap Structures Used as Filters in Microstrip Circuits" 8 (8): 336-338, 1998

3 V. Radisic, "Novel 2-D photonic bandgap structure for microstrip Lines" 8 (8): 69-71, 1998

4 D. M. Pozar, "Microwave Engineering, 3rd edition" John Wiley and Sons 337-349, 2005

5 K. C. Gupta, "Microstrip Lines and Slotlines, 2nd edition" Artech House 83-85, 1996

6 J. Lim, "Design of low-pass filters using defected ground structure" 53 (53): 2539-2545, 2005

7 J. Lim, "Application of Defected Ground Structure in Reducing the Size of Amplifiers" 12 (12): 261-263, 2002

8 F. Yang, "A novel uniplanar compact PBG structure and mixer applications" 919-922, 1999

9 C. Kim, "A novel 1-D periodic defected ground structure for planar circuits" 10 (10): 131-133, 2000

10 G. Ryu, "A Novel 3-dB Coupler for MMIC Using Air-Gap Stacked Microstrip Lines" 10 (10): 1-3, 2000

11 임종식, "A 1:6 Unequal Wilkinson Power Divider" 200-203, 2006