Abstract: Antennae in which the corresponding radiative element contains at least one multilevel structure formed by a set of similar geometric elements (polygons or polyhedrons) electromagnetically coupled and grouped such that in the structure of the antenna can be identified each of the basic component elements. The design is such that it provides two important advantages: the antenna may operate simultaneously in several frequencies, and/or its size can be substantially reduced. Thus, a multiband radioelectric behaviour is achieved, that is, a similar behavior for different frequency bands.

Abstract: The present invention refers generally to a new family of antenna arrays that are able to operate simultaneously at two different frequency bands, while featuring dual-polarization at both bands. The design is suitable for applications where the two bands are centered at two frequencies f1 and f2 such that the ratio between the larger frequency (f2) to the smaller frequency (f1) is f2/f1<1.5. The dual-band dual-polarization feature is achieved mainly by means of the physical position of the antenna elements within the array. Also, some particular antenna elements are newly disclosed to enhance the antenna performance.

Abstract: Antenna arrays which can work simultaneously in various frequency bands thanks to the physical disposition of the elements which constitute them, and also the multiband behaviour of some elements situated strategically in the array. The configuration of the array is described based on the juxtaposition or interleaving of various conventional mono-band arrays working in the different bands of interest. In those positions in which elements of different multiband arrays come together, a multiband antenna is employed which covers the different working frequency bands. The advantages with respect to the classic configuration of using one array for each frequency band are: saving in cost of the global radiating system and its installation (one array replaces several), and its size and visual and environmental impact are reduced in the case of base stations and repeater stations for communication systems.

Abstract: The present invention consists of the particular geometry of the reflectors or dispersers which constitute the anti-radar chaff cloud. Instead of using conventional rectilinear forms, in the present invention multilevel and space-filling forms are introduced. Due to this geometric design, the properties of the radar chaff clouds improve mainly in two aspects: radar cross-section (RCS) and mean time of suspension.

Abstract: A miniature broadband stacked microstrip patch antenna formed by two patches, an active and a parasitic patches, where at least one of them is defined by a Ring-Like Space-Filling Surface (RSFS) being this RSFS newly defined in the present invention. By means of this novel technique, the size of the antenna can be reduced with respect to prior art, or alternatively, given a fixed size the antenna can operate at a lower frequency with respect to a conventional microstrip patch antenna of the same size and with and enhanced bandwidth. Also, the antennas feature a high-gain when operated at a high order mode.