A Ka-Band High-Power Switchable Filtering Power Combiner MMIC in 100-nm GaN-on-Si

• Published in: IEEE transactions on industrial electronics (1982) Vol. 69; no. 10; pp. 10467 - 10477
• Main Authors: Shen, Guangxu, Zhu, Haoshen, Zeng, Dingyuan, Xue, Quan, Che, Wenquan
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.10.2022; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Band-pass filters; Bandpass filters; Co-design; Couplings; Extremely high frequencies; Filter; Filtering; gallium nitride (GaN); Impedance matching; Insertion loss; Integrated circuits; millimeter-wave switch; MMIC (circuits); monolithic microwave integrated circuit (MMIC); multifunctional; Optical switches; power combiner; Power combiners; Resonators; Transistors
• ISSN: 0278-0046; 1557-9948
• DOI: 10.1109/TIE.2021.3135633

This article presents a Ka-band switchable filtering power combiner monolithic microwave integrated circuit (MMIC), which unifies the functionalities of the switch, bandpass filter, and power combiner. For effective integration, a codesign approach is proposed by sharing the switchable resonant units and coupling matrix based impedance matching technique. Moreover, this approach offers great design freedom to realize arbitrary bandwidth and power ratios. For good return loss, the input external quality factor ( Q e ) is ensured as half of output Q e based on even-mode analysis. By analyzing the odd-mode circuit, the complex isolation element is introduced to improve the isolation between input ports. For demonstration, one prototype is implemented using a 100-nm GaN-on-Si process. Over 18-dB return loss, 1.7-dB minimum insertion loss (excluding 3-dB power ratio), >22 dB input-input isolation, and over 47-dB off -state isolation can be observed throughout 24-32 GHz. Besides, the proposed MMIC shows good linearity with a measured IP1dB of over 30 dBm within the passband, while the die size is 0.81 mm 2 .