This paper presents an innovative Direct Radiating Array (DRA) architecture exploiting aperiodic tilings of the plane. In particular, a pinwheel tiling has been selected in order to fix positions of the different radiating sources, which are constituted by properly shaped elements. Such a choice allows to achieve a good aperture efficiency and very low pseudo-grating lobes while using only two ...

A simplified model problem is used to illustrate some of the parameters controlling the radiation of sound into an ambient medium due to the growth and subsequent decay of subsonic travelling waves, such as may occur via non-linear interactions in turbulent free shear flows. It is shown that substantial sound may be generated by apparently subsonic modes as a result of their growth and decay ch...

In the literature survey concentric ring arrays using isotropic radiators are reported. Sufficient data is not available to optimization of the first sidelobe level, null to null beamwidth and directivity. In this paper, the author is proposed the problem of designing concentric ring arrays with practical radiating element. The practical radiating element is considered as dipoles to achieve opt...

We present measurements of the spectral distribution of transition radiation generated by electrons of momentum 1 to 10 GeV/c in different radiator types. We investigate periodic foil radiators and irregular foam and fiber materials. The transition radiation photons are detected by prototypes of the drift chambers to be used in the Transition Radiation Detector (TRD) of the ALICE experiment at ...

Traditionally, active control of structural radiators has approached the problem through integrating sensors and actuators on or into the structure. In such an approach, the goal is to modify the systems response to disturbance, rather than influence the disturbance path to the radiating structure. Many practical issues exist, which ultimately limit the effectiveness of such an approach. A gene...

We report a replica molding process for simultaneously forming a three dimensional metal pattern on the surface of molded polymer microstructures. This technique uses noncovalent surface forces to guide the transfer of thin metal films from the three dimensional features of high aspect ratio poly dimethylsiloxane micromolds to polymeric replicates. The utility of this technique has been demonst...

Abstract According to the findings of article, researchers looked at graphene-based hexagonal microstrip patch antennas. In place a U-shaped slot and an elliptical slot, ellipse-shaped was cut into surface radiators that were used in designs recommended. This helped improve radiation performance radiators. A frequency known as ultra-wideband (UWB) is modelling process for anticipated structures...

Renovation of the building stock in Europe is urgent to decrease environmental impact from sector and meet United Nations climate action goals. However, it often hard define a robust scenario for renovation due numerous uncertainties, which occur during production, operation end-of-life stage. One can cite loss performance insulation heating systems, replacement time installation or future ener...