References
- Lin F, Chu QX, Lin Z. A novel tri-band branch-line coupler with three controllable operating frequencies. IEEE Microwave Wirel Compon Lett. 2010;20:666–668.10.1109/LMWC.2010.2074191
- Wu YL, Zheng SY, Leung SW, et al. An analytical design method for a novel dual-band unequal coupler with four arbitrary terminated resistances. IEEE Trans Ind Electron. 2014;61:5509–5516.
- Wu YL, Shen JY, Liu YN, et al. Miniaturized arbitrary phase-difference couplers for arbitrary coupling coefficients. IEEE Trans Microwave Theory Tech. 2013;61:2317–2324.10.1109/TMTT.2013.2259501
- Fardin EA, Holland AS, Ghorbani K. Electronically tunable lumped element 90° hybrid coupler. Electron Lett. 2006;42:353–355.10.1049/el:20060129
- Gurbuz OD, Rebeiz GM. A 1.6–2.3-GHz RF MEMS reconfigurable quadrature coupler and its application to a 360° reflective-type phase shifter. IEEE Trans Microwave Theory Tech. 2015;63:414–421.10.1109/TMTT.2014.2379258
- Zhou M, Shao J, Arigong B, et al. A varactor based 90° directional coupler with tunable coupling ratios and reconfigurable responses. IEEE Trans Microwave Theory Tech. 2014;62:416–421.10.1109/TMTT.2014.2299522
- Sun J, Li C, Geng Y, et al. A highly reconfigurable low-power CMOS directional coupler. IEEE Trans Microwave Theory Tech. 2012;60:2815–2822.10.1109/TMTT.2012.2204275
- Zheng SY, Chan WS, Wong YS. Reconfigurable RF quadrature patch hybrid. IEEE Trans Ind Electron. 2013;60:3349–3359.
- Zheng SY, Deng JH, Pan YM, et al. Circular sector patch hybrid coupler with an arbitrary coupling coefficient and phase difference. IEEE Trans Microwave Theory Tech. 2013;61:1781–1792.10.1109/TMTT.2013.2252184
- Stankovic VD, Milovanovic BD, Basta JV. Analysis of circular-sector-shaped microstrip components using standard electrical CAD programs. Proc 9th Medit Electrotech Conf. 1998;1:246–250.