PIER Letters
Progress In Electromagnetics Research Letters
ISSN: 1937-6480
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By Y.-L. Yao, F.-S. Zhang, M. Liang, and M.-Z. Wang

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A planar wideband balun is proposed. The proposed balun consists of a novel slotline T-junction and three microstrip-slotline transitions. Similar to the principle of the E-plane waveguide T-junction, the slotline T-junction acts as a phase inverter. With the microstrip-slotline transition, the device employs microstrip as feedlines. The radiation loss of the slotline is reduced to improve the insertion loss by loading the slotline with a superstrate and adding via holes along the slotline. An experimental balun with a bandwidth of 128% from 2.2 GHz to 10 GHz is designed, fabricated, and measured for validation. The measured results have reasonable agreement with the simulated ones.

Y.-L. Yao, F.-S. Zhang, M. Liang, and M.-Z. Wang, "Planar Wideband Balun with Novel Slotline T-Junction Transition," Progress In Electromagnetics Research Letters, Vol. 64, 73-79, 2016.

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