Abstract:
A method for processing a data packet before transmission over a radio communications network as a succession of waveforms transmitted at positions defined by hopping codes, which are time positions or frequency positions. The packet is transmitted over a communications channel of the network by a transmitter node to a destination node. The method includes the following steps performed for each bit of the data packet to be transmitted, referred to as the current bit: calculating a hopping code at least as a function of the value of the current bit and of an encryption key generated by a pseudo-random generator, the encryption key having size greater than the maximum size of a data packet transmitted over the channel; and causing a waveform to be transmitted at the position defined by the calculated hopping code, the transmitted waveform being identical regardless of the value of the current bit.
Abstract:
One element in one of several orthogonal OVSF codes with at most 2BM elements is generated dynamically by deriving an intermediate word having (1) B least significant bits identical to the least significant bits in the reverse order of a word representing a code number SF=2B and (2) BM−B most significant bits having predetermined state. An AND circuit multiplies the bit in the intermediate word and a word representing a determined position of the element in the code produces a BM-bit product word. An EXCLUSIVE-OR operation on the bits of the product word generates the code element.
Abstract:
Method for the detection of symbols by a receiver, each symbol (S0, S1) being transmitted from a transmitter in the form of a succession of pulses (3a, 3b, . . . , 3n; 4a, 4b, . . . , 4n) representing a predetermined sequence of numerical values, the numerical values having respective nominal weights within each predetermined sequence. According to this method, a succession of pulses corresponding substantially to a symbol (S0, S1) transmitted from the transmitter is received at the receiver. A sequence of numerical values (Sr) corresponding to the said received succession of pulses is determined, the said numerical values having respective weights within the determined sequence. The received symbol is chosen as a function of the determined sequence of numerical values, the choice comprising a weighting of the numerical values of the determined sequence, chosen to re-establish the respective nominal weights of the said numerical values.
Abstract:
A method and a system for receiving an ultra-wideband signal with a self-adapting number of propagation paths. The transmitted signal includes, over a symbol time, a series of direct successive modulated pulses which propagate along a direct propagation path and secondary pulses which are associated with each direct pulse and which each propagate along a secondary propagation path. The method includes: receiving the series of direct and secondary pulses on the same receiver circuit; creating a composite correlation pattern, including a series of elementary patterns which are time-shifted in relation to a first elementary correlation pattern; calculating the value of the global correlation coefficient between each direct pulse which is associated with the plurality of secondary pulses and the composite correlation pattern, in order to obtain a global correlation value of the symbol, sum of the cross-correlation coefficients of each of the direct and secondary pulses.
Abstract:
A method and a system for receiving an ultra-wideband signal with a self-adapting number of propagation paths. The transmitted signal includes, over a symbol time, a series of direct successive modulated pulses which propagate along a direct propagation path and secondary pulses which are associated with each direct pulse and which each propagate along a secondary propagation path. The method includes: receiving the series of direct and secondary pulses on the same receiver circuit; creating a composite correlation pattern, including a series of elementary patterns which are time-shifted in relation to a first elementary correlation pattern; calculating the value of the global correlation coefficient between each direct pulse which is associated with the plurality of secondary pulses and the composite correlation pattern, in order to obtain a global correlation value of the symbol, sum of the cross-correlation coefficients of each of the direct and secondary pulses.
Abstract:
For the reconfiguration of a radiotelephone unit including components programmable in configuration modes, the invention provides a removable electronic device having stored data defining a plurality of configuration modes which is connected to the apparatus. A configuration mode is selected from the apparatus in the device. The programmable components are programmed by the device and reconfigured in accordance with the selected configuration mode data under the control of the device. The data of the configuration modes can be downloaded from a server into the device through a downloader terminal.
Abstract:
The invention relates to method and device for detecting propagation paths in pulse transmission, wherein a received signal comprises pulses on each time symbol. After synchronising a pulse-based reception, the inventive method consists (A) in determining the arrival times of pulses of the same current time symbol, (B) in generating a path hypotheses by assigning an initial score to each dated pulse, (C) in determining the arrival times of pulses of the time symbol following the current symbol, (D) in relatively comparing the arrival times of pulses of the following time symbol with the arrival times of the path hypotheses and (E) in updating scores according to the relative comparison results. Said path detecting method is suitable for pulse information transmission, in particular in UWB.
Abstract:
A method of communicating between at least one event detector sensor and a collector of event detection data transmitted by the sensor in the form of an event signalling message whose modulation is defined by at least one spreading code. The method comprises the steps implemented by the sensor of, upon detection of an event, generation of data of event detection, of reception of a synchronization message emitted by the collector, the synchronization message comprising a seed for a pseudo-random generation of at least one spreading code and of pseudo-random generation of at least one spreading code on the basis of the seed. The method furthermore comprises a step of emitting an event signalling message whose modulation is defined by the at least one spreading code generated randomly, the event signalling message comprising the event detection data.
Abstract:
The invention relates to a method of implementing operations involving the processing a radio-communication frame (CMF) in a system comprising at least three radio transmitter/receiver devices (1-5), consisting in transmitting the frame in response to a first request signal (REQ1) transmitted by a device belonging to the system (1). According to the invention, the frame is processed in the device (1) that transmitted the first request signal (REQ1) as well as in other devices belonging to the system (1, 3-5) which transmitted respective request signals (REQ2-REQ4) within a pre-determined time period.
Abstract:
The invention relates to a method of implementing operations involving the processing a radio-communication frame (CMF) in a system comprising at least three radio transmitter/receiver devices (1-5), consisting in transmitting the frame in response to a first request signal (REQ1) transmitted by a device belonging to the system (1). According to the invention, the frame is processed in the device (1) that transmitted the first request signal (REQ1) as well as in other devices belonging to the system (1, 3-5) which transmitted respective request signals (REQ2-REQ4) within a pre-determined time period.