Loading patent…
AssigneeThomson Licensing
InventorsFranck Thudor, Philippe Minard, Ali Louzir, Francoise Le Bolzer
Estimating the term…
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.
1- Antenna system for the transmission of electromagnetic signals comprising a first means for the transmission of signals of the slot antenna type and a first supply line for connecting the said first means to means for processing signals, the first supply line being electromagnetically coupled by a line/slot transition to the first means for the transmission of signals of the slot antenna type wherein it comprises a second means for the transmission of signals of the slot antenna type which is symmetric with the first means for the transmission of signals of the slot antenna type with respect to a first point P, the second means being electromagnetically coupled by a line/slot transition with the said first supply line which is in a plane passing through the first point P of symmetry, the said transition being close to the short-circuit plane of the supply line.
2- System according to claim 1, wherein it comprises a third means for the transmission of electromagnetic waves of the slot antenna type supplied by a line/slot transition which is symmetric with one of the first and second electromagnetic wave transmission means with respect to a second point and a second supply line connected in common with the first supply line to means for processing signals, the second supply line being electromagnetically coupled to the electromagnetic wave transmission means of the slot antenna type supplied by a line/slot transition and being in a plane passing through the second point of symmetry, the free end of the first and of the second supply lines being connected to a component simulating a short circuit or an open circuit at the end of one of the supply lines and an open circuit or a short circuit at the end of the other supply line.
3- System according to claim 2, wherein the length of the supply line between the component and the point of symmetry is about kλm/4 where k is an integer and λm the wavelength guided in the line, so as to restore an electrical short-circuit or open-circuit plane depending on the state of the component in the plane containing the points of symmetry.
4- System according to claim 1 wherein the means for the transmission of electromagnetic waves of the slot antenna type supplied by a line/slot transition consist of a slot of annular or polygonal shape.
5- System according to claim 4, wherein the perimeter of the slot has a wavelength of about k′═s where k′ is an integer and λs the wavelength guided in the slot.
6- System according to claim 2 wherein it further comprises a third supply line connected to a transmission means and electromagnetically coupled to the central electromagnetic wave transmission means by a line/slot transition.
7- System according to claim 6, wherein, in transmission mode, the components which are at the end of the first and second supply lines are supplied in order to simulate a short circuit.
8- System according to claims 2 or 7, wherein the component consists of a diode, a transistor, an electronic switch and a microelectromechanical system.
9- System according to claim 1, 2 or 6, wherein the supply lines are produced using microstrip technology or coplanar technology.
10- System according to claim 1, wherein the first and second means for the transmission of signals of the slot antenna type are each provided with two perturbations, the perturbations being positioned at around 45 or 135 degrees from the plane passing through the centre of said means of transmission and the first point of symmetry.