FREE IEEE PAPER A Novel 1-D Periodic Defected Ground Structure for Planar Circuits

SOME TEXT FROM PAPER A Novel 1-D Periodic Defected Ground Structure for
Planar Circuits

a measurement and results

The proposed DGS circuit, which is composed of the five-etched lattices. In this letter, we try to compare the measurement results with those of the circular lattice  cases, which are described in. Three DGS circuits for measurements have been fabricated using TACONIC CER-10 with 62-mil thick (1.5748 mm) and dielectric constant of 10. The period was kept constant to 5 mm for all three circuits. The etched rectangular area was varied with keeping the square shape. In order to compare the stopband effect of the proposed DGS circuit with previous results, the etched square area was chosen by corresponding to etched circle areas described in.

A line width of 1.46 mm was used, corresponding to 50- line for conventional microstrip line. For smaller square area the cutoff frequency is very high. As the etched area is increased the cutoff frequency becomes lower. Based on previous research, the measured results with constant number of periods show that depth and bandwidth of the stopband depend on the circle radius. In general, the stopband center frequency is a function of the period of the structure. However, the measurements on the proposed DGS circuit show that cutoff frequency and stopband characteristic depend on the etched square dimensions. The period of the proposed DGS defect affects slightly on the stopband center frequency compared with its dimension. The depth and bandwidth of the stopband for the proposed DGS circuit are inclined to depend on the number of period. The etched square area, which determines the effective inductance, characterizes the cutoff and stopband frequency characteristics of the newly proposed DGS structure. The center frequency of stopband for the proposed DGS structure is determined by the resonance frequency of each etched lattice cell. Thus, the cutoff and stopband characteristics for the proposed DGS structure can be easily estimated. Radiation loss could be occurred in some frequency range due to the etched defected area in ground plane. However, addition of the reflected and  transmitted power in the first propagation frequency band shows very low radiation level from the ground plane compared with a reported PBG circuits.

a conclusion, 

We proposed the novel etched lattice shape for the one-dimensional (1-D) DGS structure. The proposed DGS structure provides the cutoff frequency characteristic due to the effective inductance of the unit lattice, which is etched on microstrip ground plane. The proposed DGS structure is easier to control the cutoff and stopband characteristics by changing the dimensions and to fabricate. And it is much easier than circular periodic cases to analyze proposed periodic structure with finite- difference time-domain (FDTD). It is possible for the newly proposed PBG structure to apply to coplanar waveguide (CPW) and strip line for MMIC applications.

GET HERE

Rekomendasi Download: