592results about "Frequency-modulated carrier systems" patented technology

The invention discloses a time-frequency synchronization tracking and judging method based on GFSK (Gaussian Frequency Shift Keying). The method comprises the following steps: S1, positioning the initial position of a synchronization word by detecting a lead code; s2, extracting a fixed synchronization word, completing frame synchronization based on correlation matching, and positioning a starting point of an effective data segment; s3, a range cycle counter collects a central sampling point and two adjacent sampling points to form a candidate sampling point sequence; s4, dynamically and finely adjusting the range cycle counter to form a time sequence calibration sampling point sequence; s5, performing phase difference calculation on the time sequence calibration sampling point sequence, estimating continuous frequency offset and generating a compensation value; s6, applying the compensation value to construct a decision feedback equalizer with delay front and back terms; s7, performing interference suppression on the compensation sampling point sequence by using a decision feedback equalizer with delay front and back items, and outputting a soft decision value; and S8, executing three times of judgment, constructing a sliding reference sequence, and outputting a final bit judgment result. According to the method, the problem of poor GFSK demodulation robustness under Doppler disturbance is solved.

A method of decoding a received communication signal is provided. The method may comprising converting the received communication signal to the frequency domain to provide frequency domain data. The method may further comprise combining amplitudes of one or more selected frequency components of the frequency domain data, the one or more frequency components being selected according to a predefined communication symbol comprising one or more selected frequency tones corresponding to the one or more selected frequency components. The method may further comprise detecting the predefined communication symbol in the received communication signal depending on the combined amplitudes of the one or more selected frequency components of the frequency domain data.

The invention provides an anti-interference phase estimation method suitable for MSK modulation, which belongs to the technical field of anti-interference phase estimation and comprises the following steps: S1, an interference identification and marking step which comprises a signal capturing and hopping link, an interference detection algorithm link and an interference mask generation link; s2, an interference range judgment and processing step, wherein the step comprises a whole-hop interfered processing link, a partial interference processing link, a pilot frequency sequence reconstruction link and a phase estimation and compensation link; and S3, a data integration and post-processing step, wherein the step comprises a demodulation link, a data splicing link, a de-interleaving processing link, a channel decoding link and a performance feedback link. In order to solve the problems that the coding gain of a decoder is reduced and the communication performance is influenced by a traditional method when short-time sudden interference occurs in communication, the phase can still be effectively estimated by using data which are not interfered through the characteristics of MSK modulation, so that the data which are not interfered can participate in subsequent demodulation and decoding, and the communication performance is improved. And the anti-interference capability of the system is effectively improved.

The invention discloses a distribution network power line anti-interference communication method based on adaptive filtering, and belongs to the technical field of distribution network power line communication. According to the method, a communication signal adopting a frequency shift keying modulation mode is acquired from a power line coupler of a distribution network through a signal acquisition module, the communication signal is preprocessed by using a digital signal processing unit, spectral analysis is performed on the preprocessed signal, and characteristic parameters of interference noise are extracted; a coefficient vector of a finite impulse response adaptive filter is initialized based on the characteristic parameters, the order of the filter is in direct proportion to the reciprocal of the dominant interference frequency, fine adjustment is carried out based on noise energy distribution through a table look-up method or a linear mapping relation, and the weight coefficient of the filter is adjusted in real time in the communication process. The adjustment step length is dynamically adjusted according to the real-time estimated signal-to-noise ratio, and finally, the processed signal is output through the adaptive filter and data demodulation is carried out. The method is mainly used for improving the anti-interference capability and the communication reliability of the power private line communication of the distribution network.

A device for transmission of wireless power according to an embodiment of the present specification comprises: a power conversion circuit for transmitting the wireless power to a wireless power receiving device; and a communication / control circuit for communicating with the wireless power receiving device and controlling the wireless power, wherein the communication / control circuit transmits a response to a reception data packet received from the wireless power receiving device or a transmission data packet transmitted to the wireless power receiving device on the basis of a timeout period, and the timeout period is changed according to a communication speed between the communication / control circuit and the wireless power receiving device.

The invention belongs to the technical field of communication, and particularly relates to a high-robustness multi-channel frequency shift Chirp modulation signal generation method and system for a time-frequency doubly selective channel. The method comprises the following steps of: 1, calculating robust code digits based on statistical characteristics of time delay and Doppler frequency shift of an ionized layer channel; 2, based on the number of robust code bits in the step 1, setting an address code, and realizing RO-MFSCM signal mapping of binary information bits; 3, modulating and transmitting the RO-MFSCM signal based on the information mapping in the step 2, thereby realizing the transmitting process of the RO-MFSCM signal; step 4, based on the emission signal in the step 3 and the robust code digit in the step 1, the receiver carries out robust domain energy aggregation on the RO-MFSCM signal; and step 5, based on the multi-channel robust domain energy aggregation signal in the step 4, adopting a multi-channel parallel demodulation algorithm and de-mapping to realize the receiving process of the RO-MFSCM signal under the time-frequency doubly selective channel. The method aims at the transmission fading problem of the FSCM signal in the ionosphere time-frequency doubly selective channel.

Embodiments of the present disclosure provides a method for wireless communication and an apparatus, which can enable paging for ambient internet of things (IoT) devices. The method for wireless communication includes receiving, by a first communication device, a paging message. Optionally, the first communication device is an ambient IoT device or a zero-power device.

The invention relates to the technical field of communication, and discloses an AI-based adaptive data encryption method and system, and the method comprises the steps: carrying out the frequency domain transformation analysis of an original data flow, and generating a spectrum distribution feature set; the carrier frequencies are screened through a dynamic frequency selection algorithm to obtain an optimal carrier frequency range; performing phase modulation on the data bit stream, and embedding the data bit stream into a subcarrier in an optimal carrier frequency range to generate a first encrypted data stream; when the interference intensity exceeds an interference threshold value, performing directional adjustment on a frequency deviation parameter according to an interference type, and generating a second encrypted data stream; dynamically adjusting the frequency distribution parameters according to the transmission distance data to obtain a frequency distribution parameter set; and performing adaptive modulation and spectrum shaping on the second encrypted data stream based on the frequency distribution parameter set, and outputting a hidden transmission data stream. The method has the following effect that the data hidden transmission capability and the receiving and restoring accuracy in a complex environment can be improved.

The invention discloses a double-index modulation simulated radio frequency division multiplexing (AFDM) communication method. The method comprises the following steps: step 1, a transmitting end performs serial-parallel change; step 2, obtaining a transmission signal according to the index position of the joint selection AFDM activation subcarrier in the mapping table, the modulation bit mapping and the pre-chirp parameter of the activation subcarrier; step 3, obtaining a time domain signal; 4, performing parallel-serial conversion on the time domain signal; step 5, performing propagation transmission through a time-varying channel based on the time domain signal; step 6, constructing a time domain channel matrix, and performing serial-to-parallel conversion on the time domain receiving signal to obtain a receiving signal; step 7, performing channel estimation on the chirp parameter equivalent channel matrix; step 8, detecting an activated subcarrier position, an activated subcarrier modulation bit and an activated subcarrier pre-chirp parameter based on the chirp parameter equivalent channel matrix, and performing pre-chirp parameter transformation; and step 9, recovering the bit stream through parallel-serial change. The spectrum efficiency of the AFDM system is further improved, and the bit error rate is reduced.

The invention discloses a transmission type communication system and method based on low-frequency carrier waves and high-frequency modulation. The transmission type communication system and method are suitable for complex medium environments such as deep sea, strata and biological tissues. Aiming at the contradiction that the traditional low-frequency communication bandwidth is insufficient and the high-frequency communication penetrating power is poor, according to the scheme, a low-frequency carrier wave (30Hz-100kHz) and a high-frequency modulation signal (such as OFDM (Orthogonal Frequency Division Multiplexing) and 256QAM (Quadrature Amplitude Modulation)) are fused through a nonlinear signal superposition technology to generate a composite carrier wave signal, long-distance penetration is realized by utilizing the low attenuation characteristic of the low-frequency carrier wave, and meanwhile, the data rate is improved through high-frequency modulation. Application scenes comprise deep sea detection (300-meter high-definition video return), a brain-computer interface (implantable antenna transmission neural signal) and an intelligent power grid (underground pipe network monitoring). Through the physical layer-information layer collaborative design, the physical boundary limitation of traditional communication is broken through, and high penetrability, high bandwidth and strong anti-interference capability are achieved.

The invention discloses a detection and recognition integrated waveform design method, device and equipment, a medium and a product. The method comprises the following steps: dividing the time length of a waveform according to a time element, a time frame and a time slot structure; for each time slot, a time slot waveform frame structure is set to be composed of a jitter segment, a synchronization segment and a data segment, and the data segment comprises a Gaussian minimum shift keying (GMSK) modulation data segment and a linear frequency modulation (LFM) modulation data segment; respectively setting a GMSK modulation signal parameter and an LFM modulation signal parameter according to communication system demand information; performing pseudo-random hopping design on the pulse frequencies of the synchronization segment and the GMSK modulation data segment to obtain a pseudo-random frequency hopping pattern; and generating a GMSK modulation section waveform and an LFM modulation section waveform according to the GMSK modulation signal parameter and the LFM modulation signal parameter so as to form an integrated waveform. According to the embodiment of the invention, the integrated waveform can realize communication, detection and identification functions at the same time, the waveform resource utilization rate is high, and the anti-interference capability is relatively high.

The invention relates to a GMSK signal incoherent demodulation method and device. The method comprises the following steps: obtaining a state grid chart by utilizing multi-symbol detection; obtaining a matched filter according to the state grid chart; enabling the received baseband signal to pass through a matched filter to obtain a signal correlation value; obtaining a branch metric value of each state node in the baseband signal according to the signal correlation value; updating the path metric value of each state node according to the branch metric value; reserving a path corresponding to the maximum path metric value of each state node, and taking the path as a surviving path of each state node; and backtracking the survival path of each state node to obtain demodulation data of the baseband signal. According to the method provided by the invention, the state grid is obtained through multi-symbol detection, and multiple pieces of symbol information are combined, so that the problem of insufficient memory length in related technologies is solved, errors are prevented from spreading along the grid, and the error probability of symbol judgment during demodulation is reduced.

The invention provides a multi-input multi-output permutation index differential chaos shift keying communication system and method, and relates to the technical field of chaos secret communication. Generating two paths of chaotic signals in the modulator, wherein one path is used as a reference signal; delaying the other path, performing mapping permutation by using the index bit, multiplying the modulation bit subjected to space-time coding by a reference signal copy generated by permutation, generating an information signal, combining the information signal with the reference signal, and sending the information signal to a demodulator; and the demodulator is used for respectively delaying and replacing the received transmission signal, carrying out correlation operation on the delayed receiving signal and the replaced receiving signal to obtain an output signal, and carrying out comparative judgment and space-time decoding to recover the index bit and the modulation bit. According to the method disclosed by the invention, the security and the information transmission rate of a communication system are improved through different index bit mapping selection permutation rule methods; and channel fading and noise are suppressed by using multiple antennas, so that the bit error rate performance of a communication system is effectively improved.

The invention provides a multichannel HART (Highway Addressable Remote Transducer) dynamic communication system. The multichannel HART dynamic communication system comprises a modulation circuit and a demodulation circuit, the demodulation circuit of each channel comprises a hysteresis Schmitt trigger module and an analog quantity acquisition module which are parallel, the hysteresis Schmitt trigger module is configured to separate HART signals to obtain FSK signals in the HART signals, and the analog quantity acquisition module is configured to acquire the FSK signals in the HART signals. The FSK signal is converted into a digital pulse signal through the hysteresis Schmitt trigger and then is output to the controller, and the logic level of the digital pulse signal corresponds to the first frequency and the second frequency of the FSK signal; and the analog quantity acquisition module is configured to separate the HART signal to obtain a 4-20mA direct current component in the HART signal, convert the 4-20mA direct current component into a digital signal and output the digital signal to the controller.

The invention discloses a data scrambling method and device, a data descrambling method and device, equipment and a storage medium, and belongs to the technical field of communication. The data scrambling method executed by the first device comprises the steps that the first device determines a first transmission state from a plurality of transmission states of data transmission, the plurality of transmission states and a plurality of scrambling modes have a corresponding relation, and the scrambling mode corresponding to the transmission state is associated with data modulation adopted by the transmission state; the first device determines a first scrambling mode corresponding to the first transmission state; and the first device scrambles the first data to be transmitted in the first transmission state by using the first scrambling mode to obtain the second data. In the embodiment of the invention, the data transmission has a plurality of transmission states, and the plurality of transmission states have corresponding scrambling modes, so that the first data can be scrambled by using the corresponding first scrambling mode based on the current first transmission state, and the flexibility is high.

Certain aspects of the present disclosure provide a method for wireless communications at a receiver node. The receiver node may receive an indication of a modulation scheme being used for one or more data transmissions from a transmitter node. The transmitter node may transmit a data transmission to the receiver node. The receiver node may detect the data transmission from the second wireless node based on the modulation scheme indicated to the receiver node.

Aspects of the present application are related to configuring a target user equipment to alter, with minimal or no baseband processing, an incoming positioning signal, in a manner that takes into consideration various power or energy modes (e.g., regular power, low power, extremely low power) for the target user equipment. Through appropriate configuration of the positioning signal, the parameters reported, by anchor nodes, to a position-obtaining node may be shown to allow the position-obtaining node to obtain a position for the target user equipment, even though the target user equipment is in one of a plurality of low power modes.

The present disclosure provides a method for receiving wireless power by a wireless power receiver in a wireless power transmission system and a device using same, the method comprising: in a negotiation phase, transmitting request information to a wireless power transmitter and establishing a power transfer contract with the wireless power transmitter on the basis of the request information; and in a power transfer phase, receiving the wireless power from the wireless power transmitter on the basis of the power transfer contract, wherein the request information comprises information related to the number of cycles of FSK, the wireless power receiver receives data information from the wireless power transmitter through the FSK based on the information related to the number of cycles, and the wireless power receiver decodes the FSK in an interval changing according to the number of cycles.

The invention discloses a communication method, device and system and a chip. The method comprises: a network device sending a first signal to a terminal, the first signal comprising an OOK signal modulated by a sequence, the first signal carrying information of a wake-up signal, the information of the wake-up signal being carried on the OOK signal, or the information of the wake-up signal being carried on the OOK signal and the sequence. Therefore, the invention provides an optimized scheme for transmitting the information of the wake-up signal between the network equipment and the terminal.

The invention provides a handheld radio multi-mode signal rapid detection method and system, and relates to the technical field of radio, and the method comprises the steps: collecting a radio frequency signal, and carrying out the down-conversion to obtain a baseband signal; digitally sampling to obtain a digital signal sample; time domain and frequency domain features are extracted through convolution kernels of different scales based on a deep learning network; determining a modulation mode and selecting a demodulation scheme, and automatically switching to an alternative scheme when the performance of a main demodulation scheme is poor; and comparing the demodulated signal with a signal feature library to determine and display the signal type. According to the invention, the multi-mode signal detection efficiency and accuracy are improved, and the equipment complexity is reduced.

A system and a method includes receiving, by an ambient Internet of Things (A-IoT) device, an energizing signal; receiving, by the A-IoT device, a paging message from a network node, the paging message including one or more configuration parameters, determining a resource for a random access transmission from the A-IoT device using the one or more configuration parameters in the paging message, and transmitting, by the A-IoT device, a random access transmission to the network node in response to the paging message

The invention provides a high-temperature-resistant communication circuit, a communication method of the high-temperature-resistant communication circuit and a chip, and belongs to the technical field of communication processing. The circuit comprises a full-bridge driving circuit which comprises a first input end, a second input end, a third input end, a fourth input end, an output end and a working end; the communication antenna is electrically connected with the output end of the full-bridge driving circuit; the communication antenna carries out communication by using a modulation mode of frequency shift keying or binary phase shift keying; the micro-processing unit is electrically connected with the first input end, the second input end, the third input end, the fourth input end and the working end respectively and used for controlling the magnitude and the time sequence of voltage signals input into the first input end, the second input end, the third input end and the fourth input end respectively, so that continuous alternating current is generated on the communication antenna; and the current is used for setting a threshold range for the working end. The high-temperature-resistant communication circuit is used for overcoming the defect that a communication circuit capable of achieving underground high-temperature resistance is lacked in the prior art.

This application discloses a signal processing system and a related apparatus, and relates to the field of millimeter-wave radar technologies. The signal processing system includes: a signal generation unit, a frequency mixing and phase shifting unit, and N transmit ports, where the signal generation unit is configured to generate one baseband signal, where the one baseband signal includes a first baseband signal and a second baseband signal, and the first baseband signal and the second baseband signal are quadrature signals; the frequency mixing and phase shifting unit is configured to perform frequency mixing processing and phase shifting processing on the one baseband signal to obtain N radio frequency signals, where phases or frequencies of the N radio frequency signals are different from each other; and the N transmit ports are configured to respectively transmit the N radio frequency signals, where N is a positive integer. The signal processing system can solve problems of poor linearity and long settling time.

The invention relates to the technical field of signal analysis and processing, in particular to an FSK signal blind demodulation method and system in underwater acoustic communication signal analysis and processing, and the method comprises the steps: carrying out the coarse estimation of the bandwidth and carrier frequency of an underwater acoustic FSK signal; performing symbol rate estimation and timing synchronization based on an enhanced digital phase-locked loop; down-converting the received signal to zero intermediate frequency; carrying out discrete short-time Fourier transform to obtain a time-frequency domain distribution matrix of the signal; extracting time-frequency domain distribution in a time dimension by taking a symbol period as an interval, and taking out a frequency point with the strongest power at a corresponding moment to obtain a time-frequency distribution sequence of the signal; clustering the time-frequency distribution sequence by using K-means clustering, and judging the modulation order M of the FSK signal according to the contour value; and clustering the time-frequency distribution sequences into M classes, simultaneously obtaining the class to which the frequency corresponding to each sampling point in the sequences belongs, and judging the class as an M-system symbol until the blind demodulation is finished. According to the invention, blind demodulation of FSK signals with guard intervals and without guard intervals can be realized.

Various embodiments of this disclosure relate to generation and reception of signals comprising cyclically shifted basis functions. A device may obtain a set of modulation symbols and modulate a plurality of basis functions based on the set of modulation symbols to generate a signal. The plurality of basis functions may comprise cyclically shifted versions of a basis function and a periodic autocorrelation function of the basis function may comprise an ideal (e.g., perfect) periodic autocorrelation function.

The invention discloses a circuit and a method for demodulating current received by an instrument bus host, and relates to the technical field of instruments. The current demodulation circuit comprises an adder, the first input end of the adder is connected with an instrument bus MBUS to receive MBUS signals, the second input end of the adder receives reference voltage signals, and the output end of the adder outputs summing voltage signals; the resistor and capacitor charging and discharging device is connected with the output end of the summator so as to process the summing voltage signal; and the reverse input end of the comparator receives the MBUS signal, and the positive input end of the comparator receives the summing voltage signal processed by the resistor-capacitor charging and discharging device so as to determine the logic level corresponding to the MBUS signal based on the signal level of the output end of the comparator. According to the invention, the problem that the MBUS host receiving circuit cannot be compatible with all MBUS meters is solved.

This application provides a frequency offset correction method and a communication apparatus, and relates to the field of wireless communication technologies. The method includes: A second device performs down-conversion by using a first local oscillator signal, to receive a first reference signal from a first device, and adjusts the first local oscillator signal based on a receiving result of the first reference signal, to obtain a second local oscillator signal, where a frequency offset of the second local oscillator signal is less than a frequency offset of the first local oscillator signal. The second device performs down-conversion by using the second local oscillator signal, to receive a first data signal from the first device, where a guard band of the first reference signal is greater than a guard band of the first data signal.

According to various embodiments of the present disclosure, a method performed by a first device is provided, the method comprising the steps of: transmitting, to a second device, information of a frequency shift keying (FSK) set including multiple frequency shift (FS) values from among a plurality of FS values, the multiple FS values being all or some of specific FS values supported by the second device; and receiving, from the second device, a modulation signal to which the FSK set is applied.

Various aspects of the present disclosure generally relate to communication. In some aspects, a first device may determine a frequency division multiplexing (FDM) configuration for a set of component carriers associated with a cable frequency spectrum, wherein each component carrier in the set of component carriers is associated with a number of multiple input multiple output (MIMO) layers. The first device may communicate with a second device over a cable infrastructure according to the FDM configuration for the set of component carriers. Numerous other aspects are described.

The invention discloses a data processing method and a related device. In the method, the electronic equipment can generate a communication frame, processes the communication frame by respectively or in combination with technical means such as polarization coding, direct sequence spread spectrum and pilot frequency insertion, and modulates the processed communication frame by using a GFSK (Gaussian Frequency Shift Keying) technology to obtain a modulation signal. By applying the method, the processed communication frame has a high-performance GFSK frame structure, the receiving sensitivity and the anti-interference performance of a communication system where the electronic equipment is located can be improved, and more transmission rate selections can be provided.