Substrate Integrated Artificial Dielectric (SIAD) Structure for Miniaturized Microstrip Circuits

A New Calculation Method for the Characteristic Impedance of Transmission Lines With Modified Ground Structures or Perturbation

“…In practice, those have been already discussed well in the previous works by Radisic, Kim, Yun, Coulombe et al [3][4][5][6]. On the contrary, it is the aim of this work to propose a new method to calculate the characteristic impedance of those MTLs.…”

“…Furthermore, DGS has prominent advantages of being applied to microwave circuits such as filters, dividers, couplers, amplifiers, and so on [7,[9][10][11][12][13][14][15][16][17][18][19][20]. Figure 4 shows the microstrip line with SIAD structures proposed recently [6]. There are two dielectric layers with the same or different dielectric constant.…”

“…Recently, microstrip transmission lines combined by perturbation or modified ground structures (MGS) such as defected ground structure (DGS), photonic bandgap (PBG), and substrate integrated artificial dielectric (SIAD) structures have been proposed and studied popularly [2][3][4][5][6]. In addition, those structures have been widely applied to high frequency circuits such as filters, dividers, couplers, mixers, amplifiers, multipliers, baluns, and antennas [7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25].…”

“…Theoretically and practically, it is well known that all high frequency circuits should have proper design equations and matching performances based on the accurate characteristic impedance of transmission line elements. In the previous works mentioned above, the accurate characteristic impedance-based circuit applications have been one of major research topics [6,11,12,19]. Therefore it is quite important to calculate accurately the deviation of the characteristic impedance of transmission lines due to any MGS, perturbation, and arbitrary periodicity in the point of view of circuit applications as well as the transmission line itself.…”

“…It is well known that modified transmission lines (MTL) -transmission lines with a perturbation such as periodicity or modified dielectric and ground structures -have some modification in the electrical length, slow wave factor (SWF), characteristic impedance (Z c ), and effective dielectric constant from the typical values [2][3][4][5][6].…”