Abstract: A method of obtaining a nickel zinc cobalt spinet ferrite in ceramic form that includes the following: obtaining a precipitate (1) of iron, nickel, zinc, and cobalt hydroxides by co-precipitation, rinsing the precipitate (2), drying and grinding (3) the rinsed precipitate in order to obtain a powder; forming (4) into a compact by pressing the powder, and sintering (5) the compact. The sintering (5) includes a progressive temperature rise of 2° C. to 4° C. per minute, from an ambient temperature to reach a maximum temperature comprised between 950° C. and 1.010° C., maintaining at the maximum temperature for forty-five minutes to three hours, a progressive fall in temperature of 2° C. to 4° C. per minute to reach ambient temperature. The foregoing and, in particular, the sintering, enable a material to be obtained that is particularly well-adapted to the manufacture of an antenna configured for frequencies less than one gigahertz.

Abstract: A monopole wire-plate antenna that is reconfigurable in a frequency range of operation, comprising: a ground plane (1); a capacitive roof (2); a probe feed (3), which is electrically insulated from the ground plane (1), and which extends between the ground plane (1) and the capacitive roof (2) so as to electrically feed the capacitive roof (2); at least one shorting wire (4), which is arranged to electrically connect the capacitive roof (2) to the ground plane (1), and which is coated in a magneto-dielectric material (5) having a complex magnetic permeability, which varies as a function of a static magnetic field applied to the magneto-dielectric material (5).

Abstract: A monopole wire-plate antenna that is reconfigurable in a frequency range of operation, comprising: a ground plane (1); a capacitive roof (2); a probe feed (3), which is electrically insulated from the ground plane (1), and which extends between the ground plane (1) and the capacitive roof (2) so as to electrically feed the capacitive roof (2); at least one shorting wire (4), which is arranged to electrically connect the capacitive roof (2) to the ground plane (1), and which is coated in a magneto-dielectric material (5) having a complex magnetic permeability, which varies as a function of a static magnetic field applied to the magneto-dielectric material (5).

Abstract: This variable-response magnetic radiofrequency device integrated into a substrate comprises: a beam that is mobile relative to the substrate having, at each end, a transversal part mechanically anchored to the substrate and at least one central arm connecting the transversal parts to each other, at least one of the transversal parts being made out of a piezoelectric material, actuating electrodes associated with the piezoelectric material to apply a stress on the central arm, a magnetic element directly deposited on the central arm whose permeability varies as a function of the stress, and a conductive strip comprising a central part fixed to an upper face of the magnetic element opposite the lower face of this magnetic element pointed towards the central arm.

Abstract: This variable-response magnetic radiofrequency device integrated into a substrate comprises: a beam that is mobile relative to the substrate having, at each end, a transversal part mechanically anchored to the substrate and at least one central arm connecting the transversal parts to each other, at least one of the transversal parts being made out of a piezoelectric material, actuating electrodes associated with the piezoelectric material to apply a stress on the central arm, a magnetic element directly deposited on the central arm whose permeability varies as a function of the stress, and a conductive strip comprising a central part fixed to an upper face of the magnetic element opposite the lower face of this magnetic element pointed towards the central arm.