Reconfigurable negative group delay circuit with tunable group delay flatness

• Published in: International journal of RF and microwave computer-aided engineering Vol. 32; no. 6
• Main Authors: Meng, Yuwei, Wang, Zhongbao, Fang, Shaojun, Liu, Hongmei
• Format: Journal Article
• Language: English
• Published: Hoboken, USA John Wiley & Sons, Inc 01.06.2022
• Subjects: Delay circuits; Flatness; Group delay; Insertion loss; negative group delay; reconfigurable circuit; Reconfiguration; Resistors; Transmission lines; tunable group delay flatness; Varactor diodes
• ISSN: 1096-4290; 1099-047X
• DOI: 10.1002/mmce.23159

A reconfigurable negative group delay circuit (NGDC) with tunable group delay flatness is presented. The proposed NGDC is composed of an amplifier, three series resistors connecting with two transmission lines, two varactors, and a diode. By shorting different resistors through the diode, different negative group delay (NGD) times can be obtained. Two varactors are utilized to tune the flatness of the group delay. For verification, an NGDC is designed, fabricated, and measured at the center frequency of 1.0 GHz. The measured NGD time is tuned from −2.0 to −5.8 ns. The flat‐NGD bandwidth varies from 2.2% to 8.8% with ±8% group‐delay fluctuation. And the insertion loss varies from 6.5 to 13.8 dB.