End-correction network of a coaxial probe for microstrip patch antennas

Equivalent Circuit Model of Coaxial Probes for Patch Antennas

“…To validate the probe equivalent circuit derived above, a probe in a circular plate pair is studied whose analytical input impedance has been given in (1). The radii of the probe inner and outer conductor are 0.254 mm and 0.8384 mm, respectively.…”

“…The embedded dielectric is described as one term Debye model whose parameters are, respectively, 4.1 for relative infinity permittivity, 4.3 for static permittivity and 3.1831 × 10 −11 seconds for its relaxation time. Figure 8 compares both the real and imaginary parts of the probe in an infinite plate pair using (1) and (14) while the reflection coefficient Γ (n) R vanishes in the calculations. It can be seen that the analytical formula of Z A in obtained in (1) agrees very well with that obtained by the probe equivalent circuit in (14).…”

“…Many authors have found a transverse electromagnetic (TEM) field distribution across the probe aperture is a reasonable approximation for simulations of coaxial probes [1][2][3][4][5][6][7]. Therefore, a coaxial probe feeding a patch antenna can be viewed as a mode-converter which converts the TEM mode across the probe aperture into the parallel plate modes.…”

“…It is regarded as the most accurate probe feeding model for both the radiation pattern and the input impedance simulations as all the propagating and evanescent parallel plate modes are included [1][2][3][4][5][6][7]. However, magnetic-frill model requires special treatment of the probe exciting source, very dense meshes or subgridding (subcell) techniques in FEM and FDTD solvers [9][10][11][12].…”

Extended Cavity Model Analysis of Stacked Circular Disc

“…A survey of analytical models used for evaluating the input impedance of probe-fed microstrip antenna is given in reference [19]. In the present work, for purpose of computing input impedance, the end-correction network suggested by Zheng et al [20] is used. Zheng suggests that TEM aperture field approximation can provide an accurate result of input admittance, and there is no need to introduce a specific correction network for most applications.…”