3. Design specification
As this design was intended to confirm the basic concept, it was decided to build the
antenna using a best and successful approach. The specification such as the dielectric
substrate and impedance matching will be meeting and find. Appropriate components will
choose including the SMA/coaxial connector and FR4 board. A single element of square
geometry +45º and -45º slanted polarized as shown in Figure 3.2 and Figure 3.3 can be
designed for the lowest resonant frequency using transmission line model.
The substrate used is FR4 with a dielectric constant of 4.7 and a thickness of 1.6 mm. The
loss tangent of the substrate is 0.019. After all dimensions have been calculated, the design
would then be simulated in CST Studio Suite 2006 software to obtain the return loss,
radiation pattern, and VWSR.