Abstract: A lens antenna including at least one diffractive dielectric component capable of shaping a microwave frequency wave front having a wavelength comprised in a range from 1 millimeter to 50 centimeters, said diffractive dielectric component including a plurality of main microstructures formed in a substrate material with a substrate refractive index so as to form an artificial material of an effective refractive index, each main microstructure having a size of less than a target wavelength taken from said range of wavelengths, said main microstructures being laid out per zones, so as to make a surface filling level vary, the effective refractive index being a function of said surface filling level, the layout being such that the effective refractive index varies inside said one zone of said diffractive dielectric component quasi monotonously between a minimum value and a maximum value less than or equal to the substrate refractive index.

Abstract: A voltage-controlled oscillator including a dielectric resonator having a ferroelectric ceramic material placed between two metallized surfaces and biased by an electric field created by a difference in potential applied between the two surfaces as a function of a tuning frequency of the oscillator. Also included is a load impedance, and an active amplifier element coupled between the dielectric resonator and the load impedance. Further, the ceramic material is formed by metal oxides of the family: Bax;Sr(1-x) Ti(1-y)(A)y O3 (1) in which: A is a constituent configured to reduce dielectric losses of the material, and −0.4≲×≲0.9−0.001≲y≲0.2.

Abstract: A bank or identity type of magnetic card contains ferromagnetic elements that selectively absorb waves at microwave frequencies. The disclosure also relates to a reading device adapted to this card. The device has an active system and a resonant system capable of filtering the microwaves at the resonance frequencies of the ferromagnetic materials of the card to be read. The reading device, equipped with a system to measure the amplitude of the microwaves, can thus recognize the magnetic information elements on the card, through the disturbance or non-disturbance of the microwaves during the insertion of the card into the device. The value of the encoding of the card lies in fact that the information elements are hard to destroy.

Abstract: The invention is a process to manufacture a controlled-porosity ceramic material by synthesizing an aerogel produced by hypercritical drying of a high-porosity gel.Applications in the submarine acoustic field (active and passive sonars).