Abstract: An antenna for radio communication apparatus is disclosed which includes a conductive patch having two sinuous slots, a ground, a short circuit connection connecting the patch to the ground, and a feed connection connected to the patch. The antenna has a radiation diagram including a first resonant band including frequencies from 1 950 MHz to 2 100 MHz and having a width greater than 20%. The antenna can operate in a frequency range covering the UMTS, PCS, DCS and possibly GSM bands. The same type of antenna can be used on many kinds of apparatus using different frequency bands, for example frequency bands varying from one country to another. Radio communication apparatus incorporating the above antenna is also disclosed.

Abstract: The invention provides an antenna (1) for a mobile radio system, the antenna comprising two radiating conductive planes (2, 5) electrically connected together (at 4), a slot (3) in at least one of the planes, a feeder connection (6) disposed on one of the conductive planes, and a short circuit connection (7) connected to a ground (8) disposed on the same conductive plane as the feeder connection.

Abstract: A dual band transmission device includes a microstrip antenna. Its patch is provided with a short circuit for setting up quarter-wave resonant modes. A slot penetrates into the patch from its periphery, in the vicinity of the short circuit, and separates a first region from a second region, which second region nevertheless remains connected to the first region by a passage. Two resonant modes are obtained, one in the first region and the other in the first region, the passage and the second region. They can be excited from a common connecting line. According to the invention, the center frequencies and the pass-bands of the two modes are adjusted by means of a reactive component such as a capacitor which couples the first region to the second region in the vicinity of the origin of the slot. The invention applies in particular to producing a dual mode mobile telephone system conforming to the GSM and DCS standards.

Abstract: The antenna (1) of this system is a microstrip antenna. A rear edge (10) of the body (31) of its patch (6) is provided with a short-circuit (S) by which a quarter-wave type primary resonance can be excited from a connecting line (C1). A slot (17) penetrates the patch from its periphery and separates a body from a tail (33) which remains connected to the body by a passage (32). A secondary resonance mode utilises the body, the passage and the tail. It can be excited from the same connection line at a frequency which is twice that of the primary resonance. The short-circuit can be obtained by components attached to the edge of the substrate of the antenna and can then have inductive, resistive and controlled components. The invention applies in particular to implementing a two-mode mobile radio system using the GSM and DCS standards.

Abstract: An antenna for radio communication apparatus is disclosed which includes a conductive patch having two sinuous slots, a ground, a short circuit connection connecting the patch to the ground, and a feed connection connected to the patch. The antenna has a radiation diagram including a first resonant band including frequencies from 1 950 MHz to 2 100 MHz and having a width greater than 20%. The antenna can operate in a frequency range covering the UMTS, PCS, DCS and possibly GSM bands. The same type of antenna can be used on many kinds of apparatus using different frequency bands, for example frequency bands varying from one country to another. Radio communication apparatus incorporating the above antenna is also disclosed.

Abstract: A dual band transmission device includes a microstrip antenna. Its patch is provided with a short circuit for setting up quarter-wave resonant modes. A slot penetrates into the patch from its periphery, in the vicinity of the short circuit, and separates a first region from a second region, which second region nevertheless remains connected to the first region by a passage. Two resonant modes are obtained, one in the first region and the other in the first region, the passage and the second region. They can be excited from a common connecting line. According to the invention, the center frequencies and the pass-bands of the two modes are adjusted by means of a reactive component such as a capacitor which couples the first region to the second region in the vicinity of the origin of the slot. The invention applies in particular to producing a dual mode mobile telephone system conforming to the GSM and DCS standards.

Abstract: The antenna of said transmitter is a microstrip antenna. A rear edge of its patch is provided with a short circuit by means of which a quarter-wave primary resonance can be excited by a coplanar line formed by two coupling slots in an area. Separator slots separate said area from another area in which a secondary resonance can be established at twice the frequency of the primary resonance from a slotted line extending one slot of the coplanar line. The invention applies in particular to the production of a dual-mode mobile telephone to the GSM and DCS standards.

Abstract: The antenna of said transmitter is a microstrip antenna. A rear edge of its patch is provided with a short circuit by means of which a quarter-wave primary resonance can be excited by a coplanar line formed by two coupling slots in an area. Separator slots separate said area from another area in which a secondary resonance can be established at twice the frequency of the primary resonance from a slotted line extending one slot of the coplanar line. The invention applies in particular to the production of a dual-mode mobile telephone to the GSM and DCS standards.

Abstract: The antenna of this device is of the slot loop type. A conductive layer is deposited on the bottom surface of its substrate to reflect the waves transmitted or received by the resonating structure of the antenna. It is isolated from this structure to prevent parallel-plate resonance modes from being set up. A separator layer is fixed under the conductive layer to protect it from any capacitive coupling with other components of the device. It may be made of an insulating rigid foam. The invention applies to making a radiotelephone system.

Abstract: An antenna with stacked resonant structures includes: a guide line for guiding electromagnetic waves formed in a conductive layer lying in a plane, and two resonant structures having different resonant frequencies, the two structures being formed on respective opposite sides of the plane so that both are coupled directly to the line and substantially decoupled from one another by the conductive layer. The guide line is preferably of the coplanar type and the two resonant structure are preferably of the quarter-wave type. The invention applies in particular to dual-band mobile telephones.

Abstract: An antenna has a patch with a rear edge provided with a short circuit enabling a quarter-wave resonance to be established. A half-wave resonance can also be established between two lateral edges of the patch. The same coupling device couples the antenna to a transmitter or receiver for each of the two resonant frequencies. It includes a coupling strip penetrating the patch between the edges of a slot extending from one lateral edge. The antenna is particularly applicable in dual mode mobile telephone system using GSM and DCS standards.

Abstract: A multifrequency microstrip antenna in accordance with the present invention includes two zones connected to a short-circuit consisting of two conductive strips. These zones are sufficiently decoupled from each other to enable two resonances to be established in two respective different areas formed by the zones. The resonances are at least approximately of the quarter-wave type and each has an electric field node fixed by the short-circuit. The same coupling device is used to excite the two resonances. The invention applies in particular to portable telephones and to their base stations.

Abstract: A microstrip antenna includes a composite short-circuit consisting of two conductive strips. A vertical strip, in the plane of the short-circuit between the two strips, is connected to the central conductor of a coupling line forming part of the antenna and enabling the coupling with a resonance thereof, as for example to excite such resonance. The short-circuit and the vertical strip constitute two terminals for said antenna, enabling it to be easily connected to a signal processing units, such as a transmitter. The antenna described includes two zones enabling it to operate at two frequencies. The antenna has particular utility in portable telephones and their base stations.

Abstract: A quarter-wave antenna includes a patch and a ground respectively formed on the two surfaces of a substrate and mutually connected by a short-circuit. A coupling strip enters the patch via said short-circuit. It extends in the patch between two lateral slots and is connected thereto at an internal point to enable resonance of the antenna to be excited. According to the invention, the lateral slots are sufficiently narrow for a lateral coupling effect to contribute to excitation of the antenna from the edges of the strip. The invention applies in particular to mobile telephones.