A new type of directional dual-band antenna is developed for 2.4/5 GHz wireless applications. The dual-band antenna consists of a longer dipole for the lower band and a pair of shorter dipoles for the upper band. A simple coupling microstrip line is employed to excite the dipoles. Both the dual-band antenna and the feeding microstrip line are printed on the same substrate, leading to a fully pl...

The finite-difference time-domain (FDTD) technique is applied in the calculation of the S-parameters of diode mounting and waveguide-probe structures. The influence of the critical geometrical design parameters on the coupling of the coplanar feedline probe to the waveguide is investigated. A waveguide absorber based on analytic Green’s functions is used to minimize the reflections over a wide ...

An ultra wide band (UWB), reduced thickness four layers capacitive jaumann absorber (CJA) with measured reflectivity of -15 dB (minimum) from 2 GHz to 19 GHz is presented in this paper. The novel CJA is designed and implemented by modifying the jaumann absorber (JA) design. The crucial impedance matching layers of CJA are designed by conceptualizing hexagonal resistive grid on dielectric substr...

A novel perturbation approach using additional metalized via-holes for implementation of the dual-band or wide-band dual-mode substrate integrated waveguide (SIW) filters is proposed in this paper. The independent perturbation on the first resonant mode TE101 can be constructed by applying the proposed perturbation approach, whereas the second resonant mode TE102 is not affected. Thus, new kind...