Abstract: A method of authenticating data packets transmitted by terminals and received by a station, each terminal successively transmitting data packets in a plurality of different frequency bands according to a frequency hop sequence specific to said terminal, includes, for a data packet received by the station, i) measuring the frequency band in which the considered data packet has been received, ii) extracting an identification code from said considered data packet, iii) determining a theoretical frequency hop according to the frequency hop sequence associated with said extracted identification code, and iv) calculating a frequency hop deviation according to the theoretical frequency hop and to the frequency bands measured for the considered data packet and for the previous data packet. The authentication method includes determining whether data packets have been transmitted by the terminal associated with this identification code according to at least one frequency hop deviation.

Abstract: The invention relates to a system for forming an asynchronous communication network for receiving client transmitters, comprising base stations that are remote from one another, said network enabling the geolocation of the client transmitters. For this purpose, the system comprises a plurality of stationary reference transmitters, the positions of which are known and each of which transmits a specific beacon signal in a frequency band included within the frequency band of the network.

Abstract: A method for transmitting data via a terminal to a station of a digital telecommunications system. A first stream of data is encoded in data packets and a second stream of data is encoded in a frequency-hopping pattern. The data packets, in which the first stream of data is encoded, is consecutively transmitted in respective frequency bands of a frequency resource. The frequency bands are determined based on the frequency-hopping pattern in which the second stream of data is encoded.

Abstract: A method for transmitting data via a terminal to a station of a digital telecommunications system. A first stream of data is encoded in data packets and a second stream of data is encoded in a frequency-hopping pattern. The data packets, in which the first stream of data is encoded, is consecutively transmitted in respective frequency bands of a frequency resource. The frequency bands are determined based on the frequency-hopping pattern in which the second stream of data is encoded.

Abstract: A terminal (10) includes elements for transmitting data towards a station (20) in the form of radio signals, the radio signals being transmitted using a frequency resource (MC) shared between a plurality of terminals (10), characterized in that the terminal is configured to emit radio signals, the instantaneous frequency spectrum of which has a bandwidth (TOB) that is significantly lower than a frequency drift of a frequency synthesis unit of the terminal. Also disclosed are a method for using a frequency resource, a method for manufacturing terminals (10) and a telecommunication system (1).

Abstract: A method of authenticating data packets transmitted by terminals and received by a station, each terminal successively transmitting data packets in a plurality of different frequency bands according to a frequency hop sequence specific to said terminal, includes, for a data packet received by the station, i) measuring the frequency band in which the considered data packet has been received, ii) extracting an identification code from said considered data packet, iii) determining a theoretical frequency hop according to the frequency hop sequence associated with said extracted identification code, and iv) calculating a frequency hop deviation according to the theoretical frequency hop and to the frequency bands measured for the considered data packet and for the previous data packet. The authentication method includes determining whether data packets have been transmitted by the terminal associated with this identification code according to at least one frequency hop deviation.

Abstract: The invention relates to a method for estimating frequency bias negatively affecting a digital signal representative of a symbol frame, wherein said method comprises the steps of: generating the digital signal at a sampling period Te that is shorter than a predefined period of each of the symbols of the frame; calculating values for a plurality of pairs of samples of the digital signal, each value being representative of a phase difference between the samples of a pair; estimating the frequency bias negatively affecting the digital signal on the basis of the values calculated for Np pairs of samples selected such that a plurality of said Np pairs belong strictly to a single symbol in the frame. The present invention also relates to a module for implementing the estimation method, as well as to a telecommunication method and system.

Abstract: The invention relates to a system for forming an asynchronous communication network for receiving client transmitters, comprising base stations that are remote from one another, said network enabling the geolocation of the client transmitters. For this purpose, the system comprises a plurality of stationary reference transmitters, the positions of which are known and each of which transmits a specific beacon signal in a frequency band included within the frequency band of the network.

Abstract: An access network for terminals of a digital telecommunications system includes base stations adapted for receiving radiofrequency signals emitted by the terminals, each terminal a physical layer processing module adapted to form a radiofrequency signal on the basis of binary data in accordance with a predefined physical layer protocol. Moreover, for at least one base station, termed the “partial station”, an inverse physical layer processing, making it possible to extract binary data from a radiofrequency signal, is distributed between the partial station and a processing server distinct from the partial station, an inverse physical layer processing module being made up of a first inverse processing module, integrated into the partial station, and a second inverse processing module, integrated into the processing server. The invention also relates to a method of digital telecommunications.

Abstract: The invention relates to a method for estimating frequency bias negatively affecting a digital signal representative of a symbol frame, wherein said method comprises the steps of: generating the digital signal at a sampling period Te that is shorter than a predefined period of each of the symbols of the frame; calculating values for a plurality of pairs of samples of the digital signal, each value being representative of a phase difference between the samples of a pair; estimating the frequency bias negatively affecting the digital signal on the basis of the values calculated for Np pairs of samples selected such that a plurality of said Np pairs belong strictly to a single symbol in the frame. The present invention also relates to a module for implementing the estimation method, as well as to a telecommunication method and system.

Abstract: A terminal (10) includes elements for transmitting data towards a station (20) in the form of radio signals, the radio signals being transmitted using a frequency resource (MC) shared between a plurality of terminals (10), characterized in that the terminal is configured to emit radio signals, the instantaneous frequency spectrum of which has a bandwidth (TOB) that is significantly lower than a frequency drift of a frequency synthesis unit of the terminal. Also disclosed are a method for using a frequency resource, a method for manufacturing terminals (10) and a telecommunication system (1).

Abstract: A dual band transmitter (1) including: a lower band power amplifier (2) and a higher band power amplifier (3), a lower band transmit path (4) between the output of the lower band power amplifier (2) and a combining means (8); and a higher band transmit path (5); between the output of the higher band power amplifier (3) and the combining means (8). A surface mounted device includes a stub (6) having a first (61) and a second (62) end, the first end of the stub (6) being connected to the higher band transmit path (5) and the second end of the stub (6) being coupled to a switch. The second (62) end of the stub (6) is substantially closed or opened, in dependence upon the state of the switch, so that, in use, spurious harmonics are prevented from being generated in, and transmitted from, the transmitter (1).

Abstract: A frequency modulator (50, 150) for modulating a carrier signal according to a modulation data signal to provide a modulated output signal (RFout), comprises a reference signal generator (54, 154) coupled to receive the modulation data signal for performing a low frequency modulation process and for generating a reference signal modulated according to the modulation data signal, and a main synthesizer (52, 152) coupled to receive the modulated reference signal and the modulation data signal for performing a high frequency modulation process and for providing the modulated output signal at an output. Preferably, the modulated reference signal has a first modulation gain (Kr) and the modulated output signal has a modulation gain (KV) which is substantially proportional to the first modulation gain (Kr).

Abstract: A direct modulation multi-accumulator fractional-N frequency synthesizer 1 for generating a carrier signal 150 modulated by a modulation signal 170, 121 is disclosed. The frequency synthesizer includes a Voltage Controlled Oscillator, VCO 50, having a tuning port for controlling the frequency of the signal 110 output by the VCO, a variable divider 20 and a multi-accumulator sequence generator 21 for controlling the variable divider, a reference signal generator 50, a phase detector 30 and a low pass filter 40. These elements are arranged to form a Phase Locked Loop arrangement, the directly modulated output signal of which is taken from the output of the VCO, wherein in-band modulation is performed by varying the variable divider and out-of-band modulation is performed by directly applying the modulating signal to the VCO tuning port.