The embodiment of the invention provides a modulator, which comprises: a channel coding module for carrying out channel coding on data needing to be sent; a m-ary digital phase modulation module which is used for carrying out modulation mapping on the data which is subjected to channel coding and for obtaining corresponding phase data; a differential phase modulation module which is used for modulating the phase data into an initial phase; and a chirp signal generation module which is used for generating a target chirp signal according to the initial phase. By adopting the modulator to generate the target chirp signal, and initial phase can be obtained, the problem of phase ambiguity can be solved, and the chirp signal can be modulated, transmitted, received, and demodulated more accurately.

A method for providing digital communication over an acoustic channel is disclosed. The method includes dividing an operating frequency band of the acoustic channel into multiple adjacent non-overlapping subbands of an equal bandwidth, selecting subbands based on a symbol to be transmitted, generating a signal with linear frequency modulation in each of the selected subbands, combining the signals with linear frequency modulation, and transmitting the combined signals to the acoustic channel through an acoustic system, wherein slopes of linear frequency modulation for the signals with linear frequency modulation are equal.

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.

Some embodiments of the present disclosure provide a transmit point that transmits a downlink chirp sensing waveform (DL CSW) signal. A device receives the DL CSW signal and obtains a cloned chirp sensing waveform. The cloned chirp sensing waveform includes a parameter that can be uniquely associated with the device. The device transmits a UL cloned CSW signal based on the cloned chirp sensing waveform. The transmit point receives the UL cloned CSW signal and processes the UL cloned CSW signal to estimate a pose for the device and associate the estimated pose with the identity of the device.

Provided are a spread spectrum clock generator and a spread spectrum clock generation method, a pulse pattern generator and a pulse pattern generation method, and an error rate measuring device and an error rate measuring method capable of performing SSC modulation of any frequency shift according to a standard. Included are a reference signal generator 10 that generates a reference signal, a modulation waveform generator 20 that generates a modulation waveform, a modulation unit 30 that frequency-modulates the reference signal with the modulation waveform to generate an SSC modulated signal, and a modulation control unit 42a capable of arbitrarily controlling the frequency shift of the modulation waveform and a slope of the frequency shift in any time section.

A system and methods for transmission and non-coherent detection of data signals modulated by a plurality of overlapping chirps in a chirp spread spectrum communication system (CSS). Data signals input to an adaptive overlapping transmitter are modulated by a plurality of overlapping chirps and transmitted over a wireless communication system to a non-coherent receiver. The coherent receiver includes a chirp matched filter which matches the chirps to an internal chirp signal, a delay filter which delays each chirp, a multiplier which multiplies each delayed chirp by a next chirp, an integrator which sums the amplitudes of the chirps and decision circuitry which determines the polarity of each sum and outputs a stream of ones and zeroes representing the data signals.

A LoRa device for communicating sensor signals in a low power wide area network (LPWAN) includes a physical layer using Hamming encoding and Gray indexing with chirp spread signal (CSS) modulation to encode and modulate the sensor signals and a medium access layer (MAC) including a compressive sensing sub-layer which reduces encoded, modulated signals to sparse vectors. A transmission packet is formed by combining the sparse vectors with a selected set of sparse vectors representing past measurements and the incoming velocity of the sensor signals. A receiver decompresses the transmission packet by reconstructing, at a sparse recovery sub-layer of a receiver MAC layer, the encoded, modulated sensor signals. A decoder path removes the CSS modulation and Gray indexing, and Hamming decodes the sensors signals.

A LoRa device for communicating sensor signals in a low power wide area network (LPWAN) includes a physical layer using Hamming encoding and Gray indexing with chirp spread signal (CSS) modulation to encode and modulate the sensor signals and a medium access layer (MAC) including a compressive sensing sub-layer which reduces encoded, modulated signals to sparse vectors. A transmission packet is formed by combining the sparse vectors with a selected set of sparse vectors representing past measurements and the incoming velocity of the sensor signals. A receiver decompresses the transmission packet by reconstructing, at a sparse recovery sub-layer of a receiver MAC layer, the encoded, modulated sensor signals. A decoder path removes the CSS modulation and Gray indexing, and Hamming decodes the sensors signals.

A system and methods for transmission and non-coherent detection of data signals modulated by a plurality of overlapping chirps in a chirp spread spectrum communication system (CSS). Data signals input to an adaptive overlapping transmitter are modulated by a plurality of overlapping chirps and transmitted over a wireless communication system to a non-coherent receiver. The coherent receiver includes a chirp matched filter which matches the chirps to an internal chirp signal, a delay filter which delays each chirp, a multiplier which multiplies each delayed chirp by a next chirp, an integrator which sums the amplitudes of the chirps and decision circuitry which determines the polarity of each sum and outputs a stream of ones and zeroes representing the data signals.

A LoRa device for communicating sensor signals in a low power wide area network (LPWAN) includes a physical layer using Hamming encoding and Gray indexing with chirp spread signal (CSS) modulation to encode and modulate the sensor signals and a medium access layer (MAC) including a compressive sensing sub-layer which reduces encoded, modulated signals to sparse vectors. A transmission packet is formed by combining the sparse vectors with a selected set of sparse vectors representing past measurements and the incoming velocity of the sensor signals. A receiver decompresses the transmission packet by reconstructing, at a sparse recovery sub-layer of a receiver MAC layer, the encoded, modulated sensor signals. A decoder path removes the CSS modulation and Gray indexing, and Hamming decodes the sensors signals.