Title :
Design of Compact Directional Couplers for UWB Applications
Author :
Abbosh, Amin M. ; Bialkowski, Marek E.
Author_Institution :
Sch. of Inf. Technol. & Electr. Eng., Queensland Univ., St. Lucia, Qld.
Abstract :
This paper presents a simple design method for a class of compact couplers, which offer coupling in the range of 3-10 dB over an ultra-wide frequency band from 3.1 to 10.6 GHz. The proposed couplers are formed by two elliptically shaped microstrip lines, which are broadside coupled through an elliptically shaped slot. Their design is demonstrated for a 3-, 6-, and 10-dB coupling assuming a 0.508-mm-thick Rogers RO4003C substrate. Results of simulation and measurements show that the designed devices exhibit a coupling of 3plusmn1 dB, 6plusmn1.4 dB and 10plusmn1.5 dB across the 3.1-10.6-GHz band. This ultra-wideband coupling is accompanied by isolation and return loss in the order of 20 dB or better. The manufactured devices including microstrip ports occupy an area of 25 mm times 15 mm
Keywords :
coupled circuits; directional couplers; microstrip lines; ultra wideband technology; 0.508 mm; 15 mm; 25 mm; 3.1 to 10.6 GHz; Rogers RO4003C substrate; compact directional couplers; coupled circuits; elliptically shaped microstrip lines; elliptically shaped slot; isolation loss; microstrip ports; return loss; ultra wideband applications; ultra-wideband couplers; Coupling circuits; Design methodology; Directional couplers; Etching; Frequency; Manufacturing; Microstrip; Microwave devices; Slotline; Ultra wideband technology; Compact ultra-wideband (UWB) couplers; coupled circuits; directional couplers; planar coupler design;
Journal_Title :
Microwave Theory and Techniques, IEEE Transactions on
DOI :
10.1109/TMTT.2006.889150
