Abstract: Disclosed is a system for electromagnetic interrogation of RFID transponders including at least one RFID terminal configured to emit an interrogation signal at a frequency F1, at least one RFID device referred to as repeater configured to receive the interrogation signal with frequency F1 and to repeat same towards at least one RFID transponder at the frequency F2, characterized in that the at least one RFID terminal includes at least one RFID reader configured to emit an interrogation signal with frequency F0 and at least one add-on RFID device configured to perform a frequency transposition from the frequency F0 to the frequency F1, the frequencies F0 and F1 being different.

Abstract: Disclosed is a system for electromagnetic interrogation of RFID transponders including at least one RFID transponder, at least one so-called repeater RFID device and at least one RFID terminal, the at least one RFID terminal is configured to emit an interrogation signal towards the at least one repeater at a frequency F1, the at least one repeater is configured to repeat the interrogation signal with frequency F1 towards the at least one RFID transponder at a frequency F2 and the at least one RFID transponder is configured to emit a backscattered response signal at a frequency F3, the system being characterized in that the at least one repeater is configured to perform an exclusively analog frequency transposition from the frequency F1 to the frequency F2.

Abstract: Disclosed is a system for electromagnetic interrogation of RFID transponders including at least one RFID terminal configured to emit an interrogation signal at a frequency F1, at least one RFID device referred to as repeater configured to receive the interrogation signal with frequency F1 and to repeat same towards at least one RFID transponder at the frequency F2, characterised in that the at least one RFID terminal includes at least one RFID reader configured to emit an interrogation signal with frequency F0 and at least one add-on RFID device configured to perform a frequency transposition from the frequency F0 to the frequency F1, the frequencies F0 and F1 being different.

Abstract: Disclosed is a system for electromagnetic interrogation of RFID transponders including at least one RFID transponder, at least one so-called repeater RFID device and at least one RFID terminal, the at least one RFID terminal is configured to emit an interrogation signal towards the at least one repeater at a frequency F1, the at least one repeater is configured to repeat the interrogation signal with frequency F1 towards the at least one RFID transponder at a frequency F2 and the at least one RFID transponder is configured to emit a backscattered response signal at a frequency F3, the system being characterised in that the at least one repeater is configured to perform an exclusively analog frequency transposition from the frequency F1 to the frequency F2.

Abstract: An RFID communication system comprises an interrogator including a signal generator for generating an interrogation signal at a predetermined frequency f0 and a first interrogator antenna for transmitting said interrogation signal and receiving a first reply signal at a frequency f0, and processing means, and a passive transponder including a first transponder antenna for transmitting said first rely signal and receiving said interrogation signal and a chip comprising nonlinear components for generating said first reply signal in response to the interrogation signal. The interrogator is arranged to receive a second reply signal whose frequency is a multiple of the predetermined frequency f0, said multiple being either odd or even, said second reply frequency being generated by the nonlinear components of the transponder chip, said first and second reply signals being processed by the processing means of the interrogator in order to complete or improve the functionality of the system.

Abstract: The present invention relates to a RFID communication system comprising an interrogator (10) including a signal generator (12) for generating an interrogation signal at a predetermined frequency f0 and a first interrogator antenna (11) for transmitting said interrogation signal and receiving a first reply signal at a frequency f0, and processing means (13), and a passive transponder (20) including a first transponder antenna (21) for receiving said interrogation signal and a chip (22) comprising nonlinear components for generating said first reply signal in response to the interrogation signal, said first reply signal being transmitted by said first transponder antenna.

Abstract: To enable a use of a two-band type mobile telephone with a dual radiation circuit, a selector switch is placed between this dual radiation circuit and transmission channels in each of these bands. Given the emergence of the second harmonic resulting from the presence of the selector switch, the undesirable components are filtered with a filter. A part of the reactive components of this filter is between the radiating circuit and the selector switch, while the other part is in the channel to be filtered. Depending on the nature of the channel, the other part in the channel to be filtered has different values.

Abstract: To make a multiband transmitter-receiver without having to greatly increase the number of oscillators used for the modulation and demodulation of signals located in frequency bands that are very different from one another, a pair (13, 14) of programmable frequency dividers is used, installed in a transmission circuit comprising a transmission frequency oscillator (3, 30), a single transition frequency oscillator and an intermediate frequency oscillator. To go from a use (11) in one band to a use in another hand, it is enough, by means of a microprocessor (15), to modify the division coefficients of the programmable dividers by using infradyne and supradyne dividers.