A robustification method of primary two degree-of-freedom (2-DOF) controllers is proposed in this paper to control the wind turbine system equipped with a doubly-fed induction generator DFIG. The proposed robustification method should follow the following three step-procedures. First, the primary 2-DOF controller is designed through the initial form of the multivariable generalized predictive control MGPC law to ensure a good tracking dynamic of reference trajectories. Second, the robust [Formula: see text] controller is independently designed for the previous system to ensure good robustness properties of the closed-loop system against model uncertainties, neglecting dynamics and sensor noises. Finally, both above mentioned controllers are combined to design the robustified 2-DOF-MGPC controller using Youla parameterization method. Therefore, the obtained controller conserves the same good tracking dynamic that is provided by the primary 2-DOF-MGPC controller. It ensures the same good robustness properties which are produced by the robust [Formula: see text] controller. A wind turbine system equipped with a DFIG is controlled by the robustified 2-DOF-MGPC controller. Its dynamic behaviour is modelled by an unstructured-output multiplicative uncertainty plant. The controller performances are valid by comparison with those given through both controllers, which are primary 2-DOF-MGPC and robust [Formula: see text] controllers in time and frequency domains.

Microstrip antennas are useful as antennas mounted on moving vehicles such as cars, planes, rockets, or satellites, because of their small size, light weight and low profile. Since its introduction in 1985, the features offered by this antenna element have proved to be useful in a wide variety of applications, and the versatility and flexibility of the basic design have led to an extensive amount of development and design variations by workers hroughout the world.

Compact coplanar waveguide Ultra-wideband (UWB) monopole antenna with band notched characteristics is presented in this paper. The band rejection is achieved by etching a circular slot on the radiating patch. The antenna is printed on the FR4-Epoxy substrate with overall dimensions of 23.5 × 31 × 1.5 mm3. The measured results indicate that the antenna operates in the frequency range from 1.76 to 11.07 GHz and rejects the band 2.42 to 5.37 GHz with an acceptable measured input impedance over the whole operating frequency bandwidth. Furthermore, the simulated results indicate that the antenna exhibits stable radiation patterns with appreciable gain and efficiency over the whole operating band except at the notched-band. Accordingly, this antenna provides a good solution for wireless communication systems with good characteristics.

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