# Worldwide Coverage Mobile Systems for
## 4 Ku-Band Antennas Design Techniques
### Planar Antennas
This device is implemented under the constructed array. In consequence, it performs two relevant tasks; on one side it acts as a normal reflector, which increases the foresight gain of the array and, on the other side, it provides the ability to generate the dual circular polarized feature. The electromagnetic waves reflected by the frequency-selective-surface-integrated artificial magnetic conductor produces a rotation of either 90\({}^{\circ}\) or 270\({}^{\circ}\) with respect to the array electromagnetic waves that are directly radiated to the upper sphere at two frequency bands. In consequence, this behaviour enables the dual-band dual circular-polarized radiation performance. The behaviour shown by this antenna array seems to be completely distinct from most of the previously designed counterparts, whose design technologies are based on either the disturbance produced on the stacked patch or an \begin{table}
\begin{tabular}{l c} \hline \hline
**Feature** & **Value** \\ \hline Shape & square \\ Edge width & 35–55 cm \\ Type of LNB & integrated universal single or universal twin \\ Frequency range & 10.7–12.75 GHz (Ku band) \\ Polarization & vertical/horizontal \\ Gain & comparable to that with an offset of 60 cm approximately \\ Weight & 2.5 Kg–max. 7 kg \\ \hline \hline \end{tabular}
\end{table} 
Table 11: Features of the planar matrix-based antenna. \begin{table}
\begin{tabular}{l c} \hline \hline
**Feature** & **Value** \\ \hline structure & multilayer patch \\ frequency & Ku band \\ bandwidth & 42.65\% \\ gain (3 dB) & 6.08 dB \\ beamwidth & about 92\({}^{\circ}\) \\ \hline \hline \end{tabular}
\end{table} 
Table 12: Features of the wide bandwidth multilayer patch antenna. external excitation network. The antenna array is designed, simulated, and after implementation, it is tested to validate the introduced approach.Table 13 highlight the main features shown by this antenna. The so-called microstrip patch array antennas are very popular in satellite communication applications [25]. This kind of antennas shows some advantages in comparison to traditional antennas. Different techniques can be developed to implement small size patch array antennas. In [25], the authors introduce the design and implementation of a microstrip array antenna with distribution factor 2 \(\times\) 2. Table 14 shows the main features of the antenna. The array antenna was aimed at satellite communications in X band and Ku bands applications. The simulation results and measurements validate the proposed antenna showing appropriate behaviour. In [26], the authors introduce a sub-array for the construction of wide-angle scanning antenna array for satellite communications in the Ku frequency band. The proposed approach is based on the use of waveguide continuous transverse stubs, and the antenna array is composed of two sub-arrays which consists of a set of sixteen horn antennas. A regular waveguide binary power divider is used to excite the sub-array consisting of waveguide continuous transverse stubs. The authors analyse the design constraints and compute the parameters that fix the requirements to construct the continuous transverse stubs for the targeted scanning antenna array. The main features of the proposed sub-array are as follows:  
* compact structure,
* lightweight,
* construction is feasible,
* high efficiency,
* aperture efficiency: \(>\)55% (for the whole band), and
* beam-scanning range of \(\pm\)90\({}^{\circ}\). The beam-scanning range described above is obtained by mechanical rotation of the sub-arrays around its axes, the same angles. The scanning antenna approach is suitable for satellite communication terminals and radar systems. The design of a so-called Vivaldi antenna array is introduced in [27]. The antenna shows a high gain, good directivity properties, and it can operate in ultra-wide-bandwidth. The array antenna