A miniaturized lumped-element quadrature hybrid with a high density stacked structure is proposed in a 24-layer low temperature co-fired ceramic (LTCC) substrate. Stacking vertical-interdigital-capacitors (VICs) and vertically-spiral-inductors are for an entire size reduction. The transition between inductors realized in the inner space of the inductor further improves the utilization of three-dimensional space. The overall size of the quadrature hybrid is only 10.1×3.8×2.4 mm, or equivalently 0.0040×0.0015×0.0009λg3, which achieves a size reduction of 30.2%. Meanwhile, the proposed hybrid operates at 60 MHz with a fractional bandwidth (FBW) of 33.3%. The measured S11, S21, S31 and S41 are -14.5, -3.8, -3.7, and -14.2 dB within the operating frequency band, respectively, and both of the low phase imbalance and amplitude imbalance are achieved.
2. Chen, J.-H., S.-Y. Yuan, S.-R. Liou, and S.-S. Liao, "Compact planar microstrip branch-line coupler using equal difference," Microwave and Optical Technology Letters, Vol. 59, No. 13, 664-668, 2017.
doi:10.1002/mop.30364
3. Idury, S. K., R. K. Barik, S. S. Karthikeyan, and P. Kokil, "A miniaturized harmonic suppressed 3 dB branch line coupler using Hshapedmicrostrip line," Microwave and Optical Technology Letters, Vol. 59, No. 4, 913-918, 2017.
doi:10.1002/mop.30428
4. Wang, Y., X. Y. Zhang, F. X. Liu, C. H. Quan, and J. C. Lee, "A miniaturized rat-race coupler with ultra-wideband harmonic suppression," Microwave and Optical Technology Letters, Vol. 60, 1960-1963, 2018.
doi:10.1002/mop.31283
5. Bekasiewicz, A., "Miniaturized dual-band branch-line coupler with enhanced bandwidth," Microwave and Optical Technology Letters, Vol. 61, 1441-1444, 2019.
doi:10.1002/mop.31849
6. Tayebi, A. and D. Zarifi, "On the miniaturization of microstrip ring-hybrid couplers using Gielis supershapes," IETE J. Res., 1-6, Dec. 2020.
doi:10.1080/03772063.2020.1859955
7. Zhou, B., W. Sheng, and Y. Zheng, "Miniaturized and wideband lumped LTCC branch-line coupler for dozens of megahertz applications," Microwave and Optical Technology Letters, Vol. 56, No. 9, 2001-2005, 2014.
doi:10.1002/mop.28548
8. MWO, Microwave Office, , Applied Wave Research Corporation, El Segundo, CA.
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