Abstract: The invention provides a dielectric resonator oscillator DR, especially for transmission devices whose oscillating frequency may take several values. The oscillator uses two interfering conductors 30 and 31 switched so that they may or may not form a metal plane close to the dielectric resonator DR in order to vary the frequency of the oscillator while using a single resonator. The interfering conductors 30 and 31 are located in the cavity CAV close to the resonator DR and the switching means may or may not establish an electrical contact between the said interfering conductors 30 and 31.

Abstract: Compact, planar antenna made on a substrate comprising an annular slot which is dimensioned to operate at a given frequency and which is placed in a short-circuit plane of a line via which the antenna slot is fed. A second slot feed line is symmetrically disposed with respect to the first line in the line short-circuit plane common to them. Each of the lines, furnished with a port, is connected to a switching facility so as to allow the feeding of the antenna through one or the other of the two ports.

Abstract: The present invention relates to an electromagnetic wave transmission/reception source for a multireflector antenna of the Cassegrain type comprising longitudinal-radiation means (12) operating in a first frequency band and an array of n radiating elements (11) of the travelling-wave type operating in a second frequency band with the n radiating elements arranged symmetrically around the longitudinal-radiation means, the array and the longitudinal-radiation means having an approximately common phase centre, the array of n radiating elements being excited by a waveguide (15) of polygonal cross section.

Abstract: The present invention relates to a device for transmitting and/or receiving electromagnetic waves comprising at least one radiating element for radiating a circular polarization of given sense, characterized in that it comprises at least one means dimensioned and positioned with respect to the radiating element in such a way as to radiate, at the frequency of the radiating element, a circular polarization of opposite sense to that of the radiating element so as to compensate for the cross component of the radiating element. The invention applies more particularly to printed antennas operating under circular polarization.

Abstract: The present invention relates to a device for receiving and/or transmitting signals comprising an assembly of n means for receiving and/or transmitting waves with longitudinal radiation of the printed slot-antenna type, where n is an integer greater than or equal to one, and an excitation means of the microstrip-line type coupled to at least one slot line.

Abstract: The invention relates to a device for receiving and/or transmitting electromagnetic signals comprising three annular slots (20, 21, 22) which are tangent in pairs at two points P1 and P2. These slots are supplied by two supply lines (23, 24) so as to produce a line/slot transition. One of the lines 23 passes through the point P1 while the other line 24 passes through the point P2, the two lines being connected via a T-shaped junction at a common port 1. A diode 25 or 26 is mounted at the free end of each line, making it possible to simulate a short circuit or an open circuit at the end of one of the lines and an open circuit or a short circuit at the end of the other line.

Abstract: The invention reduces the size of waveguide circuits. The invention proposes to change the cross section of a waveguide in a curved part. Thus, a curved element according to the invention makes it possible at the same time to make a change in waveguide cross section.

Abstract: The present invention relates to a T-circuit produced using microstrip technology with two branches (2, 3) of identical length L2 comprising a phase-shifting element (6) producing a given phase shift &PHgr; by extending one of the branches, the T-circuit operating in broadband, the circuit comprises at least one elbow (4) extending the branch (3) without the phase-shifting element and the length L2 is equal to a multiple of &lgr;g/2 where &lgr;g is the guided wavelength.

Abstract: The present invention relates to a source antenna for transmitting/receiving electromagnetic waves comprising means for transmitting electromagnetic waves with longitudinal radiation operating in a first frequency band and means for receiving electromagnetic waves, characterized in that the means for receiving electromagnetic waves consist of a first array of n radiating elements operating in a second frequency band and a second array of n′ radiating elements operating in a third frequency band, the first and second arrays and the longitudinal-radiation means having a substantially common phase centre and the radiating elements of the first and second arrays being arranged around the longitudinal-radiation means.

Abstract: Compact, planar antenna made on a substrate comprising an annular slot which is dimensioned to operate at a given frequency and which is placed in a short-circuit plane of a line via which the antenna slot is fed.

Abstract: The present invention relates to a device for receiving and/or emitting signals comprising at least two means for receiving and/or emitting electromagnetic waves of the slot antenna type and means for connecting the said receiving and/or emitting means to means for exploiting the signals, the means for receiving and/or emitting electromagnetic waves being symmetric with respect to a point, and the connection means consisting of supply lines coupled electromagnetically to the slots of the slot antennas, which are connected on one side to a common supply line which is in a plane passing through the point of symmetry, and on the other to an electronic component enabling a short circuit or an open circuit to be simulated at the end of one of the lines and an open circuit or a short circuit to be simulated at the end of the other line.

Abstract: The present invention relates to a device for transmitting and/or receiving electromagnetic waves comprising at least one antenna with at least one radiating element transmitting and/or receiving signals of given polarization and a feed array produced in microstrip technology consisting of lines devised so as to give parasitic radiation. In this case, the feed array is devised and dimensioned in such a way that the parasitic radiation has the same direction and the same polarization as the radiation of the antenna and combines in-phase with the said radiation of the antenna.

Abstract: Multi-frequency dielectric resonator oscillator The invention provides a dielectric resonator oscillator DR, especially for transmission devices whose oscillating frequency may take several values. The oscillator uses two interfering conductors 30 and 31 switched so that they may or may not form a metal plane close to the dielectric resonator DR in order to vary the frequency of the oscillator while using a single resonator. The interfering conductors 30 and 31 are located in the cavity CAV close to the resonator DR and the switching means may or may not establish an electrical contact between the said interfering conductors 30 and 31.

Abstract: The present invention relates to a device for transmitting and/or receiving electromagnetic waves comprising at least one antenna with at least one radiating element transmitting and/or receiving signals of given polarization and a feed array produced in microstrip technology consisting of lines devised so as to give parasitic radiation. In this case, the feed array is devised and dimensioned in such a way that the parasitic radiation has the same direction and the same polarization as the radiation of the antenna and combines in-phase with the said radiation of the antenna.

Abstract: The present invention relates to a T-circuit produced using microstrip technology with two branches (2, 3) of identical length L2 comprising a phase-shifting element (6) producing a given phase shift &PHgr; by extending one of the branches, the T-circuit operating in broadband, the circuit comprises at least one elbow (4) extending the branch (3) without the phase-shifting element and the length L2 is equal to a multiple of &lgr;g/2 where &lgr;g is the guided wavelength.

Abstract: The present invention relates to a source antenna for transmitting/receiving electromagnetic waves comprising means for transmitting electromagnetic waves with longitudinal radiation operating in a first frequency band and means for receiving electromagnetic waves, characterized in that the means for receiving electromagnetic waves consist of a first array of n radiating elements operating in a second frequency band and a second array of n′ radiating elements operating in a third frequency band, the first and second arrays and the longitudinal-radiation means having a substantially common phase center and the radiating elements of the first and second arrays being arranged around the longitudinal-radiation means.