Dual-band negative group delay circuit using defected microstrip structure

This paper demonstrates a design and analysis of a dual-band negative group delay (NGD) network using defected microstrip structure (DMS). The group delays (GD) and signal attenuation (SA) of each band can be controlled independently by resistors connected across U-shaped DMS slots. For the experimental validation, the NGD network is designed and fabricated. For enhancement of the NGD bandwidth, two-stage NGD networks with slightly different center frequencies are connected in cascade. From the measurement, the GDs of -3.86±0.94 ns and -3.26±1.07 ns are obtained at 3.32-3.44 GHz and 4.63-4.76 GHz, respectively.