Abstract: A radio transmitting device configured to transmit a spread-spectrum radio signal wherein a carrier frequency changes in a predetermined set of radio channels according to a hopping sequence, the radio signal being organized in packets having each a header transmitted at a first channel in the hopping sequence comprising a detection sequence, and payload data encoding a message transmitted at following channels in the hopping sequence.

Abstract: A LoRa transmitter and corresponding receiver where the detection sequence in the preamble is phase-modulated and includes an information that encodes the position in the preamble, such as a countdown index. Nodes that wake up to receive a scheduled download can determine from this information how far the end of the detection sequence is and manage their energy consumption accordingly. The phase modulation is compatible with legacy devices.

Abstract: A method of characterizing a LoRa modulated signal or any such signals with a plurality of chirps as symbols. It foresees sampling and storing the signal, determining a phase of at least one chirp in the signal, and determining a timing error and/or a frequency error based on the phase, The timing error is extracted by the height of a discontinuous step in the phase at the position of the cyclical shift, while the frequency error is obtained by the slope of the phase. The method can be applied to a dedicated receiver for the characterization of LoRa transmitters.

Abstract: A radio transmitting device configured to transmit a spread-spectrum radio signal wherein a carrier frequency changes in a predetermined set of radio channels according to a hopping sequence, the radio signal being organized in packets having each a header transmitted at a first channel in the hopping sequence comprising a detection sequence, and payload data encoding a message transmitted at following channels in the hopping sequence.

Abstract: Transmitter for chirp-modulated radio signals comprising a chirp generator configured to generate a series of chirp signals, wherein each chirp carries an element of information encoded as a cyclic shift, and has a phase encoding an error correction code dependent form the cyclic shift of the chirp, the transmitter further comprising a modulator configured to modulate the series of chirp onto a radio signal and a radio transmitter, transmitting the radio signal. receiver for chirp-modulated radio signals, comprising a clock unit and a demodulator configured for demodulating a series of received chirps signal, the demodulator having a dechirp unit, configured for determining a cyclic shift of each received chirp relative to a base chirp and an error correction code based on a phase of the received chirp, the receiver having a synchronism correction unit configured to detect and/or correct an error in the clock unit based on the error correction code.

Abstract: A radio-transmitting device comprises a radio interface operating in a predetermined frequency band, operatively arranged for modulating a carrier having a frequency in the frequency band, while switching the frequency of the carrier among several hopping frequencies in the frequency band, according to a hopping sequence, to obtain a spread-spectrum modulated signal, wherein the spread-spectrum modulated signal includes, in a preamble portion, a plurality of sync words, each combined with at least one instance of a sequential index, the sync words being transmitted at different frequencies, and a data portion following the preamble portion and including a plurality of frequency hops.

Abstract: An extension of the LoRa modulation with an improved ranging mode. A master and a slave device exchange a request and a reply that contain sequences of chirps that are carefully aligned in time, frequency, and preferably also phase, such that the master device can ascertain the propagation delay to the slave by demodulating the reply. Request and reply include chirps having different slopes, preferably slopes of equal absolute value and opposite sign. The slope diversity permits an unbiased estimation of the Doppler shift.

Abstract: A LoRa receiver for processing digital chirp spread-spectrum modulated signals with an advanced module for the determination of the timing error and/or of the frequency error arranged to estimate a position of a frequency discontinuity in each symbol, extract one or more frequency-continuous fragments out of each symbol, dechirp the coherent fragments, determine a timing error, and/or a frequency error, and/or a modulation value, and/or a SNR.

Abstract: Advanced modulation and demodulation schemes for LoRa or equivalent chirp spread spectrum transmissions, with differential modulation and symbol repetition improve the sensitivity in combination with soft demodulation methods.

Abstract: Transmitter for chirp-modulated radio signals comprising a chirp generator configured to generate a series of chirp signals, wherein each chirp carries an element of information encoded as a cyclic shift, and has a phase encoding an error correction code dependent form the cyclic shift of the chirp, the transmitter further comprising a modulator configured to modulate the series of chirp onto a radio signal and a radio transmitter, transmitting the radio signal. receiver for chirp-modulated radio signals, comprising a clock unit and a demodulator configured for demodulating a series of received chirps signal, the demodulator having a dechirp unit, configured for determining a cyclic shift of each received chirp relative to a base chirp and an error correction code based on a phase of the received chirp, the receiver having a synchronism correction unit configured to detect and/or correct an error in the clock unit based on the error correction code.

Abstract: A LoRa receiver for processing digital chirp spread-spectrum modulated signals with an advanced module for the determination of the timing error and/or of the frequency error arranged to estimate a position of a frequency discontinuity in each symbol, extract one or more frequency-continuous fragments out of each symbol, dechirp the coherent fragments, determine a timing error, and/or a frequency error, and/or a modulation value, and/or a SNR.

Abstract: Advanced modulation and demodulation schemes for LoRa or equivalent chirp spread spectrum transmissions, with differential modulation and symbol repetition improve the sensitivity in combination with soft demodulation methods.

Abstract: A hopping spread-spectrum wireless network for IoT applications operating in a predetermined frequency band, with mobile device that have unsynchronized local frequency references and receiving gateways that are capable of detecting whether modulated radio signals will collide in frequency in a collision time interval, and blanking the signals in the collision time. Preferably, the frequency band is subdivided into a sub-bands, and the mobile devices adapt the width of the sub-bands used for transmission based on a synchronization status indicative of the frequency error of the local frequency reference.

Abstract: A hopping spread-spectrum wireless network for IoT applications with mobile device that have unsynchronized local frequency references. The transmitters use hopping sequences defined in term of the relative differences of frequencies, in such a manner that a receiver can determine the hopping sequence of a transmission despite the presence of a large frequency error.

Abstract: A ranging and positioning system comprising transmitters and receiver nodes communicating together by chirp-modulated radio signals, that have a ranging mode in which ranging exchange of signals takes place between a master device and a slave device that leads to the evaluation of the range between them. The slave is arranged for recognizing a ranging request and transmit back a ranging response containing chirps that precisely aligned in time and frequency with the chirps in the ranging requests, whereupon the master can receive the ranging response, analyze the time and frequency the chirps contained therein with respect to his own time reference, and estimate a range to the slave.

Abstract: Method of timing, in a receiver, a radio signal generated in and transmitted from a transmitter, the radio signal comprising a series of frequency chirps, the system including: receiving the radio signal from the transmitter; synthesizing projection vectors comprising a series of frequency chirps that are a complex-conjugate image of those comprised in the radio signal the projection vectors being time-shifted relative to one another by determined shift intervals of time; multiplying the received radio signal by the projection vectors and accumulating the results; interpolating the accumulating results to determine a peak time shift.

Abstract: A hopping spread-spectrum wireless network for IoT applications with mobile device that have unsynchronized local frequency references. The transmitters use hopping sequences defined in term of the relative differences of frequencies, in such a manner that a receiver can determine the hopping sequence of a transmission despite the presence of a large frequency error.

Abstract: A hopping spread-spectrum wireless network for IoT applications. The network includes mobile devices with unsynchronized local clocks that transmit including, in a preamble portion, a plurality of sync words, each combined with at least one instance of a sequential index. The hopping frequencies at which the sync word are transmitted are different. This arrangement helps detection and synchronization of the signals, despite the unavoidable frequency mismatches and collisions.

Abstract: A hopping spread-spectrum wireless network for IoT applications operating in a predetermined frequency band, with mobile device that have unsynchronized local frequency references and receiving gateways that are capable of detecting whether modulated radio signals will collide in frequency in a collision time interval, and blanking the signals in the collision time. Preferably, the frequency band is subdivided into a sub-bands, and the mobile devices adapt the width of the sub-bands used for transmission based on a synchronization status indicative of the frequency error of the local frequency reference.

Abstract: A wireless communication system, comprising one or several nodes (A) equipped by a wireless radio interface that is adapted for transmitting digital messages modulated in the form of a series of frequency chirps, for example, LoRa-modulated radio signals. The message is received simultaneously by several base stations (C, D, E), and a server (S) is arranged for dividing the frames by the diverse stations and recombining a corrected frame for the intended recipient (B) based on error codes. Advantageously, the base stations being adapt their timing error compensation strategy when the error codes indicate a corruption of the message.