47 results about "Chirp spread spectrum" patented technology

The invention discloses an anti-multipath and anti-frequency offset satellite communication method based on chirp spread spectrum modulation joint architecture, and relates to the technical field of satellite or data chain communication, the method comprises the following steps: mapping input K bit information into a modulation symbol K, K belongs to {0, 1,..., N-1}; s02, a corresponding chirp baseband signal s [n] is generated according to the modulation symbol K, and the expression of the chirp baseband signal s [n] is as follows: n = 0, 1,..., N-1; and S03, carrying out digital-to-analog conversion on the chirp baseband signal. According to the invention, through integrated design of spread spectrum and modulation depth, and by use of the complete orthogonal autocorrelation characteristic of chirp signals and an FFT demodulation mechanism, the problems that a traditional architecture has significant bottlenecks in the aspects of resource efficiency, dynamic adaptability, anti-interference capability and the like and is difficult to meet high-performance communication requirements in a high-speed moving and complex multipath scene are effectively solved; the anti-multipath and anti-Doppler performance is significantly improved, and the calculation and resource overhead of the receiving end is greatly reduced.

The invention discloses a wireless ranging method and system based on a programmable logic architecture, and belongs to the technical field of indoor positioning, and the method comprises the following steps: receiving an original data frame of a processing module, adding a synchronization frame header and a synchronization frame tail, then carrying out linear frequency modulation spread spectrum coding to form a ranging request frame, recording the sending time, and sending the ranging request frame to a target receiving end; after a ranging response frame is received, a decoded data frame is generated through decoding processing such as time domain filtering and peak detection, coherent accumulation is carried out by taking a first target code element as a reference, a target array is extracted, interpolation refining is carried out to obtain a fine time component, and the arrival time is obtained through multipath elimination. According to the method, main signal energy is enhanced through coherent accumulation, multi-path interference is suppressed in combination with interpolation refinement and time domain filtering, the time measurement precision is improved, and software and hardware cooperative efficient distance measurement is realized.

The invention discloses a chirp spread spectrum photon terahertz communication perception integrated system. The system comprises a coherent light source module used for generating two beams of coherent single-frequency optical carrier signals; the signal modulation module is used for generating a baseband chirp spread spectrum communication sensing integrated signal and modulating the signal to one beam to form a carrier signal; the integrated signal transmitting module is used for taking the other beam of single-frequency optical carrier signal as an optical local oscillator signal, and after the optical local oscillator signal is coupled with the carrier signal, a terahertz communication sensing integrated signal is generated and radiated through optical down-conversion; the communication receiving module is used for performing frequency conversion and demodulation on the received terahertz communication sensing integrated signal and recovering communication information in the signal; and the radar receiving module is used for performing de-chirp and target information estimation on the received terahertz communication sensing integrated signal. According to the system, the advantages of a photon terahertz architecture are fully exerted, and an ultra-wideband chirp spread spectrum integrated signal is generated, so that a communication sensing integrated system with high spread spectrum gain and high energy efficiency is realized.

A communication method that includes using a software app on a local computing device to initiate sending a message to a recipient, determining that a cellular network is not available to the app, and sending, by the app, the message as a digital packet by a personal area network (PAN) connection to a device paired with the local computing device. The device uses chirp spread spectrum modulation to send the packet in an L-band of spectrum to a satellite

The present application belongs to the technical field of communications. Disclosed are a signal transmission method and apparatus, an information configuration method and apparatus, and a readable storage medium. The signal transmission method in the embodiments of the present application comprises: a first device generating a first signal on the basis of first information and a received carrier signal, wherein the first signal is a backscattered chirp spread spectrum (CSS) modulated signal; and sending the first signal.

The invention discloses a signal transmission method and device, communication equipment and a readable storage medium, and belongs to the technical field of communication, and the signal transmission method comprises the steps that first equipment carries out backscattering modulation according to a to-be-transmitted information bit and a second signal to obtain a first signal; wherein the second signal is a carrier signal of the first signal; the first signal comprises at least one first signal unit, each first signal unit comprises two chirp spread spectrum CSS symbols, the average powers or reflection coefficients of the two CSS symbols are different, and other parameters, except the average powers and the reflection coefficients, of the two CSS symbols are the same; the information bits to be transmitted are modulated through the frequency of each CSS symbol in each first signal unit; and sending the first signal.

A tactile sensing system of a robot may include: a plurality of piezoelectric elements disposed at an object, and including a transmission (TX) piezoelectric element and a reception (RX) piezoelectric element; and at least one processor configured to: control the TX piezoelectric element to generate an acoustic wave having a chirp spread spectrum (CSS) at every preset time interval, along a surface of the object; receive, via the RX piezoelectric element, an acoustic wave signal corresponding to the generated acoustic wave; select frequency bands from a plurality of frequency bands of the acoustic wave signal; and estimate a location of a touch input on the surface of the object by inputting the acoustic wave signal of the selected frequency bands into a neural network configured to provide a touch prediction score for each of a plurality of predetermined locations on the surface of the object.

The invention relates to a target sensing method based on a communication signal, and the method comprises the steps: receiving a communication signal transmitted by an active target, the communication signal being a signal combining frequency shift keying and linear frequency modulation spread spectrum modulation; carrying out carrier demodulation on the communication signal to obtain a double-channel baseband signal; performing digital beam forming processing on the double-channel baseband signal to obtain sum beam data and difference beam data; performing matched filtering processing on the sum beam data and the difference beam data; performing multi-pulse coherent accumulation processing on a matched filtering result to obtain distance-Doppler information; determining angle information of the active target based on a ratio relationship between the sum beam data and the difference beam data; and determining the distance, Doppler velocity and angle of the active target according to the distance-Doppler information and the angle information.

The invention discloses a signal transmission method and device, an information configuration method and device and a readable storage medium, and belongs to the technical field of communication, and the signal transmission method comprises the steps that first equipment generates a first signal according to first information and a received carrier signal, and the first signal is a backscattered chirp spread spectrum CSS modulation signal; and sending the first signal.

A communication method that includes using a software app on a local computing device to initiate sending a message to a recipient, determining that a cellular network is not available to the app, and sending, by the app, the message as a digital packet by a personal area network (PAN) connection to a device paired with the local computing device. The device uses chirp spread spectrum modulation to send the packet in an L-band of spectrum to a satellite

The present invention discloses an indoor positioning hardware processing module and a processing method thereof, which belong to the field of indoor positioning technology. The processing module is deployed in an indoor positioning system including a programmable logic module and a host computer, and includes a main program module, a host computer interface module, a frame filling and frame parsing module and a ranging logic control module. The main program module generates a linear frequency modulation spread spectrum reference signal and executes system initialization and main control processes; the host computer interface module realizes device registration and data return; the frame filling and frame parsing module completes the application layer processing of the frame data; the ranging logic control module coordinates the ranging interaction with the programmable logic module. The processing method includes the steps of signal initialization, device registration, frame data processing, ranging cycle and result return. The present invention improves the automated ranging efficiency and communication reliability of the indoor positioning system through module division of labor and coordination mechanism, and solves the problem of low process automation in the prior art.

The invention relates to an ultra-wideband navigation signal tracking method and device based on linear frequency modulation spreading codes, and belongs to the technical field of satellite navigation. The method comprises the following steps: receiving an ultra-wideband navigation signal and multiplying the ultra-wideband navigation signal by a local in-phase carrier and a local orthogonal carrier respectively to obtain an in-phase component and an orthogonal component; acquiring a local linear frequency modulation spreading code output after phase calculation, phase quantization, code generation and signal transmission delay binding; acquiring a local pseudo-random spreading code output after signal transmission delay binding; combining the two types of spread spectrum codes to generate delayed, instant and advanced spread spectrum codes, and performing coherent integration on the spread spectrum codes, an in-phase component and an orthogonal component which are divided into three paths; calculating a phase error and a time delay error between the current receiving signal and a local carrier according to a coherent integration result; and finally, generating repeated carrier waves and two types of spreading codes based on error feedback so as to circularly realize ultra-wideband navigation signal tracking. According to the method, the complexity of ultra-wideband navigation signal tracking can be reduced.

Radio receiver for a radio transmission system (100, 110, 120, 130), wherein a message (101) either (a) is sent as a whole data packet (102) in the radio transmission system (100) without forward error correction, or (b) is sent in the radio transmission system (110) as a data packet (103) divided into sub-data packets (103_1-103_n), wherein the sub-data packets (103_1-103_n) are sent sequentially and are individually decodable or (c) is sent in the radio transmission system (120) as a data packet (104) divided into partial data packets (104_1, 104_n), wherein the partial data packets (104_1, 104_n) are sent one after the other, or (d) is transmitted in the radio transmission system (130) as a data packet (106) using a chirp spreading spectrum, wherein the radio receiver has the following features: an independent power supply in the form of a battery (204, 304) or a photovoltaic arrangement (305), and a first antenna (201, 301) for receiving radio signals from a radio transmitter of the radio transmission system (100) and a second antenna (202, 302) for receiving the radio signals from the radio transmitter of the radio transmission system (100), wherein the first (201, 301) and second antenna (202, 302) are provided for receiving a uniform type of radio signal, wherein the radio receiver adjusts its reception range to the first antenna (201, 301) or second antenna (202, 302) depending on the reception of the radio signals from the radio transmitter.

A device for communicating via satellite includes a transceiver unit operable to transmit a signal comprising a packet encoded by modulation of a carrier wave from the device to a satellite, a controller unit coupled to the transceiver unit and operable to control operations of the transceiver unit; and a personal area network (PAN) connection that communicatively couples the device with a smartphone. The transceiver unit modulates the carrier wave with the packet via chirp spread spectrum modulation or similar and sends the signal to the satellite within a designated band of frequency such as the L-, S-, C-, X-, Ku, Ka, Q-, or V-Band of spectrum.

The invention relates to an ultra-wideband navigation signal generation method and device based on linear frequency modulation spreading codes, and belongs to the technical field of satellite navigation. The method comprises the following steps: generating a linear frequency modulation spreading code of a data / pilot branch by using a phase quantization model meeting collaborative optimization constraints of generation complexity and sidelobe suppression performance; generating a pseudo-random spreading code of the data / pilot branch; generating a data code containing a navigation message; according to the pseudo-random spreading code and the linear frequency modulation spreading code of the pilot frequency branch, generating a digital baseband signal of the pilot frequency branch and performing digital-to-analog conversion; according to the data code and the pseudo-random spreading code and the linear frequency modulation spreading code of the data branch, generating a digital baseband signal of the data branch, and performing digital-to-analog conversion; and generating a complete ultra-wideband navigation signal according to the analog baseband signal of the data / pilot frequency and the radio frequency carrier. According to the method, the generation complexity of the ultra-wideband navigation signal can be greatly reduced, and a key technical support is provided for the application of the ultra-wideband navigation signal.

A device for communicating via satellite includes a transceiver unit operable to transmit a signal comprising a packet encoded by modulation of a carrier wave from the device to a satellite, a controller unit coupled to the transceiver unit and operable to control operations of the transceiver unit; and a personal area network (PAN) connection that communicatively couples the device with a smartphone. The transceiver unit modulates the carrier wave with the packet via chirp spread spectrum modulation or similar and sends the signal to the satellite within a designated band of frequency such as the L-, S-, C-, X-, Ku, Ka, Q-, or V-Band of spectrum.

The invention discloses a linear frequency modulation spread spectrum modulation system and modulation method based on a neural network, which are realized by converting a CSS modulation process into a neural network component, support the generation of various CSS variant signals, and are compatible with various neural network platforms at the same time. The method comprises the following steps: firstly, mapping input effective load data into a starting frequency vector by adopting a frequency selection module, and providing an accurate frequency starting point for subsequent modulation; secondly, the frequency modulation module generates a CSS signal component through a transposition convolution layer; and finally, the complex signal generation module converts the modulation result into a standard complex signal format, and ensures that the output signal is completely compatible with the existing SDR platform and the commercial LoRa receiving node. According to the method, the basic neural network component is utilized, the problems that an existing CSS modulator is poor in expandability and hardware portability are solved, and an efficient and flexible modulation scheme compatible with various CSS variants is provided for application of the Internet of Things.

The application discloses a communication method, device, communication equipment and readable storage medium, and belongs to the technical field of communication. The communication method of the application embodiment comprises the following steps: a first device performs a first operation; wherein the first operation comprises at least one of the following: respectively sending a plurality of reader-to-device (R2D) signals to a plurality of second devices, and respectively receiving a plurality of device-to-reader (D2R) signals sent by the plurality of second devices; the R2D signal is a chirp spread spectrum (CSS) modulation signal; the D2R signal is a CSS modulation signal; each two R2D signals in the plurality of R2D signals have orthogonality or quasi-orthogonality, and each two D2R signals in the plurality of D2R signals have orthogonality or quasi-orthogonality.

The application relates to an over-the-horizon chirp spread spectrum communication signal-to-noise ratio estimation method, a system and a storage medium, and relates to the technical field of over-the-horizon communication. The method comprises the following steps: S1, acquiring a received signal in over-the-horizon chirp spread spectrum communication, performing despread and Fourier transform on the received signal to obtain corresponding frequency spectrum data; S2, extracting a useful signal amplitude and a noise signal amplitude from the frequency spectrum data; S3, calculating a log-domain amplitude ratio feature of the received signal by using the useful signal amplitude and the noise signal amplitude; and S4, inputting the log-domain amplitude ratio feature into a pre-trained signal-to-noise ratio estimation model to obtain a signal-to-noise ratio estimation value of the received signal; wherein the pre-trained signal-to-noise ratio estimation model is a piecewise linear regression model trained based on training samples under different signal-to-noise ratio conditions. Compared with the prior art, the application can avoid increasing the calculation overhead of additional discrete Fourier transform, thereby reducing the calculation complexity and accurately calculating the signal-to-noise ratio under different intensity noise environments, and the real-time performance and the estimation accuracy are considered.

The invention discloses an information transmission method and device, communication equipment and a readable storage medium, and belongs to the technical field of communication. The information transmission method comprises the following steps: a first device performs chirp spread spectrum CSS modulation on bit information to be transmitted to obtain a CSS modulation signal; transmitting the CSS modulation signal; a CSS symbol in the CSS modulation signal satisfies at least one of the following items: representing different bit information through different starting frequency sweeping frequency points in the CSS symbol; the number n of bits carried by one CSS symbol and the number N of initial frequency sweeping frequency points or initial frequency sweeping frequency points used for modulation in the CSS symbol meet the following condition: 2n = N; the number N of initial frequency sweeping frequency points used for modulation in the CSS symbols meets the condition that N is smaller than or equal to M, and M represents the number of frequency points or the number of frequencies in a CSS frequency sweeping range or a CSS frequency sweeping bandwidth; for the CSS symbol with the initial frequency sweeping frequency point, the frequency sweeping frequency point or the frequency sweeping frequency in the symbol period of the CSS symbol and the frequency sweeping time meet at least one of the following items: a linear function relation and a nonlinear function relation.

The invention provides a radio station adaptive joint coding modulation method applied to a severe channel environment, and the method supports interconnection and intercommunication of a plurality of radio stations, and comprises a transmitting end and a receiving end. Wherein the data processing process of the sending end is as follows: data to be sent and a reference signal form a data frame according to a frame format, and scrambling interleaving processing is carried out; performing polarization coding on the processed data frame; sCMA coding is carried out; self-adaptive chirp spread spectrum modulation is carried out; the data processing process of the receiving end is as follows: the receiving end radio station synchronizes the received chirp modulation signal and then performs incoherent demodulation; channel signal-to-noise ratio estimation is carried out; sCMA multi-user detection is carried out on the demodulated data information; and performing CRC (cyclic redundancy check). According to the invention, interconnection and intercommunication of a large number of radio stations can be realized by occupying less time-frequency resources in a severe channel environment.

The present application relates to the technical field of communications, and discloses a signal transmission method and apparatus, a communication device, and a readable storage medium. The signal transmission method in embodiments of the present application comprises: a first device performing backscatter modulation on the basis of an information bit to be transmitted and a second signal, so as to obtain a first signal, wherein the second signal is a carrier signal of the first signal, the first signal comprises at least one first signal unit, each first signal unit comprises two chirp spread spectrum (CSS) symbols, the average powers or reflection coefficients of the two CSS symbols are different, the parameters of the two CSS symbols other than the average power and the reflection coefficient are the same, and said information bit is modulated by means of the frequency of each CSS symbol in each first signal unit; and sending the first signal.

A system and a method thereof for performing modulation and demodulation based on a chirp spread band technique are disclosed. A system for performing modulation and demodulation based on a chirp spread band technique according to one embodiment of the present disclosure includes: a transmitter that transmits a chirp signal; and a receiver that receives and demodulates the chirp signal. The transmitter determines the number of data bits (M) modulated in a unit symbol based on a first residual carrier frequency offset and a spreading factor (SF), and transmits a first chirp signal obtained by modulating the first data bits in at least one symbol according to the determined number of data bits modulated in the unit symbol to the receiver. The receiver may transmit information indicating a second residual carrier frequency offset detected based on the received first chirp signal to the transmitter.

The application relates to a target sensing method based on a communication signal, which comprises the following steps: receiving a communication signal transmitted by an active target, wherein the communication signal is a signal combined by frequency shift keying and linear frequency modulation spread spectrum modulation; performing carrier demodulation on the communication signal to obtain a double-path baseband signal; performing digital beam forming processing on the double-path baseband signal to obtain sum beam data and difference beam data; respectively performing matching filtering processing on the sum beam data and the difference beam data; performing multi-pulse coherent accumulation processing on the matching filtering results to obtain distance-Doppler information; determining angle information of the active target based on a ratio relationship between the sum beam data and the difference beam data; and determining the distance, Doppler velocity and angle of the active target according to the distance-Doppler information and the angle information.

Data transmission method, corresponding transmitter and receiver, data transmission system and computer program product. The invention relates to a data transmission method using chirp-type spread spectrum modulation between a transmitter (3a, 3b, 3c, 3d) and a receiver (2), the method using frames comprising an alignment section portion of at least 2*M-1 chirps, and a payload portion composed of groups of M chirps. The invention also relates to a transmitter (3a, 3b, 3c, 3d), a receiver (2), a communication system (1) and a computer program product implementing the method. Figure to be published with the abstract: Figure 9

The invention relates to a chirp spread spectrum-based unmanned aerial vehicle cluster network high-precision wireless clock synchronization system and method, the system is composed of an unmanned aerial vehicle root node and a plurality of unmanned aerial vehicle slave nodes, and synchronous data interaction is carried out among the nodes of the whole network based on a chirp spread spectrum CSS communication link; an unmanned aerial vehicle root node organizes whole-network synchronous circulation by constructing a dynamic super-frame structure comprising a broadcasting stage, a grouping interaction stage and a random access stage. An unmanned aerial vehicle slave node completes time coarse alignment in the broadcasting stage and analyzes a scheduling table, and completes two times of RTT measurement with the unmanned aerial vehicle root node strictly according to a scheduling time slot in the grouping interaction stage; in the measuring and resolving process, a slave node extracts a fine timestamp by combining with high-precision arrival time calibration of a chirp spread spectrum baseband, frequency offset estimation, clock correction calculation after motion compensation and local clock calibration are sequentially completed by combining with an estimation result of the baseband on the relative motion speed, and competitive network access is performed through a random access stage in a free state. According to the invention, nanosecond-level high-precision clock synchronization is realized.

A chirped spread spectrum-based wireless clock synchronization method and system overcomes the limitation of signal sampling rate on wireless clock synchronization accuracy through chirped spread spectrum modulation and demodulation, achieving arrival time estimation with oversampling period resolution. The clock difference between the client and server is measured using round-trip time delay measurement. A Kalman filter is used to optimally estimate the clock difference and clock speed. The FPGA's MMCM dynamically adjusts the clock phase, achieving higher resolution clock adjustment step sizes at lower clock frequencies, thus overcoming the limitation of system clock frequency on synchronization accuracy. This invention combines a high-precision arrival time estimation method and a high-precision clock adjustment method, and can be used for high-precision wireless clock synchronization in communication systems, radar systems, data acquisition systems, astronomical observation systems, and other systems, meeting the synchronization requirements of multiple distributed devices.

The application discloses a backscattering communication and sensing integrated system and method based on a chirp spread spectrum signal, and relates to the technical field of wireless communication.The system comprises a chirp spread spectrum signal source, a backscattering device and a receiving end.The chirp spread spectrum signal source is used for sending a chirp spread spectrum modulated signal.The chirp spread spectrum modulated signal reaches the backscattering device through a reflection link, and the chirp spread spectrum modulated signal reaches the receiving end through a direct link.The backscattering device modulates the chirp spread spectrum modulated signal, and then transmits the modulated signal to the receiving end.The receiving end is used for realizing signal reception.The receiving end demodulates the signal of the direct link, estimates the sensing parameters of the reflection link, and realizes signal demodulation of the reflection link.The application has the beneficial effect of increasing the communication range and coverage area, and can realize sensing of the backscattering device at a long distance.

This invention discloses a linear frequency modulated (LFM) spread spectrum signal modulation and demodulation method based on index modulation. The method includes the following steps: creating an index set to map the bit information to be transmitted into index combinations; generating a transmitted LFM spread spectrum signal using the index combinations; creating a preamble to generate a transmitted frame signal using the preamble; performing incoherent demodulation on the received frame signal; calculating estimated parameters and setting a threshold based on the estimated parameters; extracting an initial index combination based on the threshold; and updating the initial index combination using an index matching demodulation algorithm to obtain the demodulated bit information. This invention, applied to LFM spread spectrum systems, can improve the transmission rate of the LFM spread spectrum system and simultaneously enable rapid recovery of bit information using a low-complexity demodulation algorithm.