A New Defected Ground Structure for Different Microstrip Circuit Applications

A New Defected Ground Structure for Different Microstrip Circuit Applications

Blog Article

In this paper, a microstrip transmission line combined with a new U-headed dumb-bell defected ground structure (DGS) is investigated.The proposed DGS of two U-shape slots connected by a thin transverse slot is placed in the ground plane of a microstrip line.A finite cutoff frequency and attenuation pole is observed and thus, the equivalent circuit of the DGS unit can be represented by a parallel LC resonant circuit in AGRIMONY series with the transmission line.A two-cell DGS microstrip line yields a better lowpass filtering characteristics.The simulation is carried out by the MoM based IE3D software and in the experimental measurements a vector network analyzer is used.

The effects of the transverse slot width and the distance between arms of the U-slot on the filter response curve are studied.This DGS is utilized for different microstrip circuit applications.The DGS is placed in the ground of Indole 3 Carbinol a capacitive loaded microstrip line and a very low cutoff frequency is obtained.The DGS is adopted under the coupled lines of a parallel line coupler and an improvement in coupling coefficient is noticed.The proposed DGS is also incorporated in the ground plane under the feed lines and the coupled lines of a bandpass filter to improve separately the stopband and passband performances.