49 results about "Frequency-shift keying" patented technology

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.

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.

An audio authentication and identity verification system and method that encodes dynamic cryptographic information across the audible and inaudible spectrum (0 Hz→30 kHz, scalable to 124 kHz). A rolling acoustic signature simultaneously embeds identity, time, date, and GPS location using a hybrid of frequency shift keying (FSK), phase shift keying (PSK), Morse style pulse duration modulation, and time domain multiplexing. To guarantee post-event privacy and integrity, the system further incorporates a dual custody audio architecture in which every authenticated recording is split into complementary bit interleaved segments stored separately, and the decryption key is fragmented via Shamir 3-of-5 secret sharing—preventing unilateral access or tampering. The system establishes a tamper proof, real time, and offline capable authentication layer that functions in air, through conventional microphones, and via dedicated emitter hardware.

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.

This invention relates to a biomimetic compound eye wide-area sensing and communication system for unmanned swarms, comprising a collaborative optical signal modulation and transmission unit, a wide-area biomimetic compound eye photoelectric sensing unit, and a spatial optical communication and positioning calculation unit. By structurally encoding control commands and employing frequency shift keying modulation, digital information is converted into near-infrared modulated optical signals, enabling spatial information propagation. The receiving end utilizes a biomimetic compound eye structure to converge wide-area field-of-view optical signals and completes photoelectric conversion through a spatial position sensor. Multi-channel signal processing is combined to achieve communication signal demodulation and feature extraction. Based on this, multi-dimensional features are constructed and spatial position calculation is performed, realizing integrated information interaction and relative position perception between nodes. This invention does not rely on radio frequency communication links and satellite navigation systems. In complex electromagnetic countermeasures and navigation-constrained environments, it can achieve stable communication and collaborative sensing for unmanned swarms, possessing advantages such as strong anti-interference capability, good concealment, and high environmental adaptability.

The invention discloses a dual-frequency dual-channel synchronous current generation method and device, and belongs to the field of electrical equipment and electrical engineering, and the method comprises the following steps: converting hexadecimal information needing to be sent into binary information through a main control unit; the main control unit performs frequency shift keying modulation on the binary information aiming at the two communication frequency bands to obtain two paths of modulation signals; mixing the two paths of modulation signals, outputting one path of pulse width modulation signal with a dual-frequency characteristic, carrying out direct current isolation and high voltage isolation processing on the pulse width modulation signal, and outputting the pulse width modulation signal to a metal oxide semiconductor field effect transistor; and the metal oxide semiconductor field effect transistor carries out resistor switching to generate characteristic current. The method can effectively resist the single-frequency interference problem, reduce the active heating value, support long-time injection without over-temperature protection, and can effectively resist the power-frequency interference.

The invention relates to the field of noise elimination, in particular to a method, a medium and equipment for eliminating FSK noise in a cockpit voice record. Comprising the following steps: determining whether an FSK noise section and a reference audio section on a to-be-processed recorded audio are background noise or not; if the FSK noise section and the reference audio section are both non-background noise, the frequency domain similarity between the first discriminant audio and the first reference audio is greater than a first similarity threshold, and the time domain similarity between the first discriminant audio and the first reference audio is greater than a second similarity threshold, determining that the first discriminant audio and the first reference audio are not background noise; if so, the audio of the FSK noise segment is replaced with the audio in the reference audio segment. According to the method, the characteristics of CVR multi-channel recording are utilized, the audio similarity of two microphone channels is compared, noise is eliminated in an automatic mode, the method is suitable for rapidly processing single or multiple records, and the cabin sound analysis efficiency is improved.

Methods, systems, and devices for wireless communication are described. Some wireless communication systems may support channel state information (CSI) reporting for frequency shift keying (FSK) modulated frequency modulated continuous waveforms (FMCW). A first network node may receive a first set of parameters for generating a CSI report associated with an FMCW communication type. The first network node may generate the CSI report according to the first set of parameters based on measurement information corresponding to an FMCW-based reference signal. The CSI report may indicate a second set of parameters for FSK-modulated (FMCW) communication between the first network node and a second network node. The first network node may send the CSI report to a second network node prior to the FSK modulated FMCW communication between the first network node and the second network node.

This disclosure relates to glitch suppression for FSK demodulation. According to an embodiment, a glitch suppression circuit includes a first-stage averaging circuit with programmable length, a second-stage averaging circuit, and a hysteresis comparator. The first stage uses a FIFO buffer to implement recursive shifting and averaging to process a binary input signal. The second stage provides moving average filtering. The hysteresis comparator uses a programmable threshold set based on the peak signal value to generate a clean output signal. This circuit removes glitches from the input signal of the frequency shift keying (FSK) demodulator while maintaining signal integrity at high bit rates. The programmable parameters allow for optimization based on desired glitch characteristics and system requirements.

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.

A programmable digitally-controlled oscillator (DCO) for time-domain symbol generation is described in an embodiment. The programmable DCO comprising: an odd number (n) of multi delay cells (MDGs) to form a ring oscillator, the odd number (n) being equal to or more than three, and the odd number (n) of MDCs being adapted to generate n-1 number of multiplexed phases for phase shift keying (PSK) modulation, wherein each of the n number of MDCs comprises: two or more multi jitter cells (MJCs), each of the two or more MJCs being adapted to activate a corresponding delay for tuning a period of one cycle to represent a corresponding bit of a frequency shift keying (FSK) modulation, wherein each of the two of more MJCs comprises: two or more replica basic delay cells (BDCs) configured to adjust jitter, wherein each of the two or more replica BDC is adapted to provide a predetermined jitter target and comprises: two or more sets of reconfigurable inverter gates having different channel lengths and corresponding frequency ranges, the two or more reconfigurable inverter gates being selectable based on a target frequency range. A backscattered software-defined radio (SDR) transmitter system is also described in an embodiment.

A system includes a surface device, preferably positioned on a surface, a downhole device, and a wireline communications system. A downlink communication between the surface device and the downhole device occurs via Hopped Frequency Shift Keying (HFSK) voltage-modulated signals. An optional uplink communication between the downhole device and the surface device may occur via Frequency Shift Keying (FSK) current-modulated signals. The downhole device may comprise an addressable switch.

The present disclosure relates to a technical field of signal processing, and provides a Gauss frequency shift keying (GFSK) signal receiving method and apparatus, an electronic device, and a storage medium. The GFSK receiving method includes: in a GFSK receiver, obtaining, based on a receiving end, a frequency value after phase differencing; performing inverse Gaussian filtering on a decoded frequency value through a preset inverse Gaussian filter, and obtaining a filtered frequency value, where the inverse Gaussian filter is a filter constructed based on composition information of a transmitted signal; and performing accumulation based on the filtered frequency value, making a decision, and obtaining decoded data of a received signal. The present disclosure can improve decoding performance of the GFSK receiver.

A receiver device comprises receiving circuitry configured to receive a radio signal modulated using frequency shift keying or phase shift keying, the radio signal comprising a plurality of successive symbol intervals, differential detector circuitry configured to multiply a signal for a current symbol interval with a first reference signal and output a first output signal for the current symbol interval, wherein the first reference signal corresponds to a conjugate of a signal for a first symbol interval preceding the current symbol interval and multiply the signal for the current symbol interval with a second reference signal and output a second output signal for the current symbol interval, wherein the second reference signal corresponds to a conjugate of a signal for a second symbol interval preceding the first symbol interval, in which the conjugate of the signal for the second symbol interval has been phase adjusted in dependence on a previous phase decision for the first symbol interval preceding the current symbol interval, combining circuitry configured to combine the first output signal for the current symbol interval and the second output signal for the current symbol interval to obtain a combined signal for the current symbol interval, and decision circuitry configured to output a phase decision for the current symbol interval in dependence upon the combined signal.

The invention discloses an underwater acoustic quaternary frequency shift keying signal carrier frequency estimation method, which comprises the following steps of: performing periodogram method power spectrum estimation on an underwater acoustic signal which is identified as quaternary frequency shift keying, and finding four frequency points with the strongest energy; the first frequency point, the second frequency point, the third frequency point and the fourth frequency point are sorted from small to large, and the difference values of the adjacent frequency points after sorting are calculated as the first difference value, the second difference value and the third difference value. The underwater acoustic quaternary frequency shift keying signal carrier frequency estimation method provided by the invention is established on the basis that an identified communication signal is a quaternary frequency shift keying signal, so that the carrier frequency estimation method provided by the invention only aims at the condition that the power spectrum frequency does not decline or declines by one in a periodogram method; when two or more frequencies are lost, the signal can be directly identified as other signals and cannot enter the process, so that the effects of minimum calculation amount, simplest implementation and highest estimation precision are achieved.

The application relates to the technical field of charging systems, and particularly discloses an electric energy / signal synchronous transmission system and method for electric vehicle charging piles, wherein the charging pile system is composed of multiple module stacks, and taking a double module as an example, the system comprises a charging pile module circuit 1, a charging pile module circuit 2, a signal generation system 1, a driving system 1, a signal demodulation system 1, a signal generation system 2, a driving system 2 and a signal demodulation system 2. The charging pile module circuit 1 comprises a three-phase full-bridge rectifier circuit 1, a double active bridge DC / DC circuit 1 and a double active bridge DC / DC circuit 2, and the charging pile module circuit 2 comprises a three-phase full-bridge rectifier circuit 2, a double active bridge DC / DC circuit 3 and a double active bridge DC / DC circuit 4. The application adopts a novel signal transmission mode, embeds signals into output voltage ripples by controlling the switching frequency of power tubes and combining a frequency shift keying modulation mode, and realizes bidirectional transmission of signals through modulation and demodulation of the output voltage ripples. The system electric energy and signal transmission share a coupling channel, the signal transmission process does not affect the output electric energy quality, meanwhile, the two double active bridge circuits in the module can be fully utilized for double-frequency parallel transmission, the signal transmission rate is increased, the system has good anti-noise capability, and the flexibility of system application is improved.

The present disclosure relates to high bit rate FSKD dither compensation circuit. According to embodiments, a wireless power receiving device includes a demodulator that generates carrier period data from a received frequency shift keying modulated signal having dither. A high pass filter circuit extracts offset values from the carrier period data. A polyphase filter circuit includes a plurality of smoothing filters and distributes the extracted offset values among the filters based on a dither pattern length. A compensation circuit stores smoothed offset values from the polyphase filter circuit in a dither table during an evaluation window and applies the stored values to compensate the carrier period data during a subsequent demodulation.

The invention discloses a DPSN open set modulation identification method based on instantaneous frequency feature extraction, and belongs to the field of radio communication signal modulation identification. The implementation method comprises the following steps: calculating the instantaneous frequency of a communication signal sample; on the basis of a P-GRU calculation unit, establishing a DPSN expansion parameter selection neural network model for modulation mode open set identification; the DPSN expansion parameter selection neural network model mainly comprises a feature extraction module and a classification layer module; carrying out feature extraction on the instantaneous frequency by the model, and carrying out sequence expansion and residual link in the feature extraction process; the extracted feature vectors pass through a classification layer of open set recognition, probability distribution P of classification labels is output, and the maximum value in P is the modulation mode label corresponding to the communication signal; outputting the label of the modulation mode to complete identification of the modulation mode; training to obtain a trained DPSN expansion parameter selection neural network model; and realizing frequency shift keying intra-class identification of complex electromagnetic environment signals and open set identification of non-frequency shift keying signals according to the trained model.

A communication method and apparatus are provided, to improve frequency shift keying (FSK) demodulation performance of a low-power device. After determining at least two orthogonal frequency division multiplexing (OFDM) subcarriers, a first device sends an FSK signal to a second device on the at least two OFDM subcarriers, and the second device demodulates the FSK signal. In this way, FSK transmission of a low-power receiver can be compatible with OFDM, so that the FSK demodulation performance can be improved.

The present application relates to a kind of disaster relief material transport multi-robot cooperation system, belong to robot technical field.The cooperation system includes power supply, servo motor, track, digital signal processing DSP, wireless communication module, Gauss frequency shift keying GFSK wireless data radio, laser radar, inertial measurement unit IMU, GPS and encoder.The present application adopts distributed control mode in multi-material transport cooperation robot system, so that the autonomy, flexibility, reliability and response speed of each robot in system are improved.The present application designs more suitable for disaster relief scene multi-transport robot cooperation system, designs by the track drive suitable for rugged road, sensor fusion positioning for the environment interference after disaster and multi-transport robot cooperation control under the urgency requirement of disaster relief time.

The invention relates to a rail transit transponder system and method based on a variable minimum frequency shift keying technology. The system comprises a transmitter subsystem and a receiver subsystem which are connected through a wireless radio frequency signal, wherein the transmitter subsystem comprises a transmitter signal processing unit, an MSK modulation unit, a signal amplification unit and a radio frequency transmitting antenna which are connected in sequence; the MSK modulation unit is used for modulating the digital signal processed by the transmitter signal processing unit into an MSK signal; the receiver subsystem comprises a radio frequency receiving unit, an MSK (Minimum Shift Keying) demodulation unit and a receiver signal processing unit which are connected in sequence; and the MSK demodulation unit demodulates the received digital signal. Compared with the prior art, the method has the advantages that the data transmission reliability is ensured, the data transmission rate is improved, and the stronger anti-interference capability is realized.

According to various embodiments of the present disclosure, provided is a method performed by a first device, the method comprising the steps of: transmitting, to a second device, a carrier wave (CW) or an energizing signal (ES) to which a first modulation is applied with symbol timing information or clock information on the basis of one modulation scheme among amplitude shift keying (ASK), phase shift keying (PSK), or frequency shift keying (FSK); and receiving, from the second device, an uplink signal (UL signal) to which a second modulation is applied on the basis of the symbol timing information or the clock information, wherein the first modulation and the second modulation have the same modulation scheme or different modulation schemes.

The invention discloses a frequency offset estimation method of an FSK (Frequency Shift Keying) signal, and belongs to the technical field of frequency estimation. The method comprises the following steps: firstly, converting a signal on a time domain to a frequency domain through sliding discrete Fourier transform for analysis and processing, then calculating power near a frequency point position, then searching a maximum power value, judging whether the maximum power value is greater than a threshold, and finally comparing a frequency position corresponding to the power value greater than the threshold with an original position of the frequency point, and calculating the frequency offset. The method is suitable for FSK signals with different modulation orders, can be used in an FDMA system for processing continuous signals, and has the advantages of wide application range and low complexity.

A receiver, including: a sampling circuit configured to convert a received analog signal into a digital signal; a variance determination circuit configured to determine a phase difference variance of the digital signal; and a frequency shift keying (FSK) discrimination circuit configured to discriminate, based on the phase difference variance, whether the received analog signal is an FSK-modulated signal.

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.

The utility model relates to a frequency shift keying signal receiving device, a road side unit and an ETC system. The frequency shift keying signal receiving device comprises an automatic gain control circuit, a phase-locked loop circuit, a frequency mixing circuit, a surface acoustic wave filter circuit, a logarithmic detection circuit and a shaping circuit. The automatic gain control circuit adjusts the 2FSK signal and outputs a first signal; the phase-locked loop circuit generates a local oscillator signal; the frequency mixing circuit performs frequency mixing processing on the first signal and the local oscillator signal and then outputs a second signal; the surface acoustic wave filter circuit filters the second signal to obtain a third signal; the logarithmic detection circuit detects the third signal to obtain a baseband envelope signal; the shaping circuit carries out shaping processing on the baseband envelope signal to obtain a baseband data signal. According to the utility model, discrete components are adopted to replace integrated chips, so that noise can be reduced, signal receiving sensitivity can be improved, and the compatibility problem caused by different chips adopted by different manufacturers can be solved.

The application relates to the technical field of radiation source identification, and discloses an FSK signal radio frequency fingerprint feature extraction method, an identification method and a system.The extraction method is characterized in that the following steps are included: S1, feature extraction: based on instantaneous frequency wavelet transformation, fingerprint features capable of describing a radiation source are extracted, and the wavelet coefficients of the instantaneous frequency of the FSK signal are taken as the fingerprint features.The application solves the problems of the prior art, such as low FSK signal radio frequency fingerprint feature extraction capability, poor distinguishability of FSK signal fingerprint features under low signal-to-noise ratio, and the like.

The present invention discloses a method for minimum frequency shift keying (MSK) demodulation of underwater acoustic communication based on an extended Kalman filter, comprising: a transmitting end transmitting an MSK signal including an information sequence and a training sequence; a receiving end receiving the MSK signal transmitted through an underwater acoustic channel, performing channel estimation based on the training sequence, and obtaining a channel impulse response; introducing the channel impulse response into the construction of an observation matrix of the extended Kalman filter, forming a phase tracking model incorporating channel information by modifying the Jacobian matrix, and continuously tracking the phase of the received signal through the phase tracking model to achieve minimum frequency shift keying demodulation. The present invention utilizes the phase continuity characteristic of the MSK signal, fully exploits the correlation between the signal phase and the transmitted code element, performs phase tracking on the received signal at the receiving end, and achieves high-precision demodulation in an underwater acoustic environment. The method has a stronger ability to resist multipath interference, can effectively utilize the channel impulse response, and significantly improves the reliability of underwater acoustic communication.

The invention discloses an improved C-dump converter energy and signal simultaneous transmission strategy. In order to solve the problem that energy in a follow current stage of a traditional C-dump converter can only be fed back to an excitation power supply and power generation energy output cannot be realized, a follow current loop suitable for a power generation state is constructed by adjusting the connection position of an energy storage capacitor in a circuit, so that the control independence of each phase is maintained and the use of devices is not increased; and effective output of power generation energy is realized. The flyback converter is adopted to widen the voltage output range and reduce the output voltage fluctuation at the same time. In order to realize synchronous transmission of energy and signals, a frequency shift keying modulation method is used, and ripple signals containing communication data are embedded in output voltage; and a receiving end performs information demodulation by using fast Fourier transform, so that an information transmission system is simplified. According to the scheme, the system complexity is remarkably reduced, and the output electric energy quality of the switched reluctance generator is effectively improved.

This application provides multiple information transmission methods. An example method performed by a user equipment includes, receiving, in an envelope-demodulation scheme, first indication information and second indication information that are respectively modulated based on different modulation schemes, where a combination of the first indication information and the second indication information indicates whether to wake up a terminal device; and determining, based on the combination of the first indication information and the second indication information, whether to wake up the terminal device. For example, the first modulation scheme is an on-off keying modulation scheme, and the second modulation scheme is a frequency shift keying modulation scheme.