Patent application number | Description | Published |
20080237346 | SYSTEM FOR SECURE COMMUNICATION BETWEEN A CONTACTLESS CARD READER AND A CARD - The invention relates to contactless communication systems between a moving object and a reader, in particular systems in which the moving object is a chip card or an identification tag. To enhance communication security, the card reader transmits, from a radiofrequency transmission antenna separate from the main communication antenna, a disturbance signal having the same frequency and modulation type characteristics as the response signal expected from the card to the reader; the electromagnetic coupling between this separate antenna and the antenna of the reader is, however, such that the latter does not “see” the transmitted disturbance but detects only the response from the card; on the other hand, the environment between the card and the reader sees the response from the card only mixed with the disturbance signal. | 10-02-2008 |
20100297938 | LARGE BAND INDUCTIVE ANTENNA FOR CONTACTLESS COMMUNICATION SYSTEMS - Signal transmission and/or reception device, by contactless inductive coupling comprising at least one structure forming one or several antennas, said structure comprising a plurality of conducting links ( | 11-25-2010 |
20110133889 | DEVICE FOR LOCATING OBJECTS BY RFID COMMUNICATION - The invention relates to the locating and identifying of objects with radiofrequency communication by inductive coupling, without electrical contact, between a reader and a tag. The device includes an array of N fixed RFID markers of RFID tag type, with inductive antennas placed at known positions, N being an integer greater than 1 and an RFID tag reader provided with a fixed reading inductive antenna passing in proximity to the N markers. The position of the N markers with respect to the inductive reading antenna is such that the mutual inductance between the inductive antenna of any marker and the inductive reading antenna is zero when no object to be located is present in the vicinity of the array of markers, and nonzero when an RFID tag is present in the vicinity of the marker considered. A coupling is established in the presence of a mobile tag in proximity to a marker. | 06-09-2011 |
20120238899 | DATA TRANSFER SYSTEM AND ASSOCIATED MANAGEMENT METHOD - A method for managing a data transfer system includes recovering energy at peripheral devices, and wireless transfer recovered energy to a base by synchronizing RF signals transmitted by double-loop antennas. Synchronizing includes implementing a listening phase to detect a radio-frequency signal transmitted by said central base, and either sending an RF signal that is synchronous with the detected signal or transmitting a signal at a predetermined frequency depending on whether an RF signal is detected at the base. The method includes, in response to receiving a signal from the peripheral device at that frequency, causing the base to recover the received signal and to re-transmit at the predetermined frequency to the peripheral devices. This signal synchronization enables simultaneous energy transfer from peripheral devices to the central base while avoiding mutually destructive effects between said signals. | 09-20-2012 |
20130207857 | HIGH-FREQUENCY ANTENNA - The invention relates to an inductive antenna formed from at least two pairs of segments ( | 08-15-2013 |
20130271343 | ANTENNA FOR A MOIST ENVIRONMENT - The invention relates to an inductive antenna, comprising: a first planar conductive winding ( | 10-17-2013 |
20140285016 | System for transferring energy by electromagnetic coupling - The invention relates to a device ( | 09-25-2014 |
20150054623 | LOCATING DEVICE FOR EVALUATING THE DISTANCE BETWEEN AN RFID LABEL AND AN INTERFACE - A locating device for determining a distance of an RFID tag with respect to an interface between two media comprising an inductive coupling antenna and a sensor for determining a distance between the antenna and the interface. There is an energizing circuit configured to energize the antenna to generate an electromagnetic field with various successive amplitude values and a detection device for detecting an electromagnetic field response from the RFID tag. There is a processing circuit configured to determine several pairs of information, each pair including: a distance between the antenna and the interface and a minimum electromagnetic field value detected by the detection device from the RFID tag at the determined distance between the antenna and the interface. The processing circuit also evaluates the distance between the RFID tag and the interface as a function of the several pairs. | 02-26-2015 |