32 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.

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.

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.

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.

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 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 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.

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 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.

The invention relates to a method for transmitting data (56) of a functional device (12) to a mobile evaluation device (14) by means of a light signal, wherein the operating state of the functional device (12) is signaled, on the basis of a control signal, so as to be visually detectable by emitting visible light (20) by means of a signal lamp (16), the control signal being modulated according to a specified modulation method (48), the emitted light is detected by a light detection unit (22) of the evaluation device (14), the light detection unit having light sensor elements (24) which are arranged in rows (26) and columns (28), detected light values of the light sensor elements are read successively in rows or successively in columns, and light values are evaluated by the evaluation device in order to determine the transmitted data. According to the invention, a frequency shift keying method using a plurality of modulation frequencies (f0, f1, f2, f3) is used, wherein, in the case of the light values (80) being read in rows, light value data relating to the light values of at least one column, as an evaluation column (74), is evaluated by the evaluation device in order to determine at least one of the modulation frequencies.

Methods, systems, and devices for wireless communication are described. A device may modulate a set of information bits using on-off keying (OOK) or frequency shift keying (FSK), or both. The device may generate a wake-up signal (WUS) waveform using the chirp signal and the modulated set of information bits. The device may transmit the WUS waveform via at least a portion of the WUS bandwidth and a portion of the WUS duration. The WUS waveform may occupy at least a portion of the WUS bandwidth and at least a portion of the WUS duration according to a pattern based on the modulated set of information bits.

The application relates to the field of signal processing, in particular to a ranging method and device, an ultrasonic sensor and a readable storage medium. The frequency shift keying encoding method comprises the following steps: acquiring a sequence code group corresponding to a digital signal to be transmitted, wherein the sequence code group comprises a plurality of binary symbols arranged in sequence; and performing frequency shift keying encoding on the sequence code group, wherein the frequency is changed at the moment when the carrier amplitude is the highest, so as to generate an analog signal formed by the frequencies corresponding to the binary symbols arranged in sequence, and the analog signal carries the digital signal information. The application can improve the smoothness of the change of mechanical vibration, reduce the distortion of the signal, and also reduce the loss degree of related components.

The utility model discloses a frequency shift keying communication circuit with adjustable output power and detectable load power, which comprises a local driving unit and a far-end slave equipment unit, and is characterized in that the local driving unit comprises a local master control module, a local detection and voltage regulation module and a local line transmission module; the remote slave equipment unit comprises a remote line transmission module, the local detection and voltage regulation module comprises a Hall current sensor and a programmable resistor chip, and the programmable resistor chip and the local line transmission module are both connected with the Hall current sensor; the Hall current sensor, the programmable resistor chip and the local line transmission module are connected with the local master control module, and the local line transmission module is connected with the far-end line transmission module. According to the utility model, the output power can be remotely adjusted, the load power can be detected in real time, the design cost can be reduced, the circuit safety can be improved, and the circuit can be widely applied to the technical field of frequency shift keying communication.

The invention relates to the technical field of wireless communication, and provides a multi-channel parallel frequency hopping receiving method and system, and the method comprises the steps: obtaining an analog signal received by an antenna, and converting the analog signal into a multi-channel digital signal through a multi-channel analog-to-digital converter; processing each path of digital signals and different local oscillator signals through a digital mixer and a band-pass filter to generate down-conversion signals; inputting the down-conversion signal to an integrator to obtain an integration result; the integration result is input into a comparator for comparison, and one path of down-conversion signal with the maximum value is obtained and serves as a frequency shift keying modulation signal containing data; and inputting the frequency shift keying modulation signal to a demodulator to obtain demodulated information data, and completing dehopping of the frequency hopping signal. According to the invention, the problems of easy data loss and slow synchronization speed in the existing hopping spread spectrum communication de-hopping process are solved.

A communication device (10) includes a reception part (20) demodulating a signal subjected to frequency shift keying by using binary values. The reception part has: a detection part, detecting a first bit, which is one of high and low bits along a time line; and an estimation part, estimating presence of a second bit based on a length of the ongoing time during which the first bit cannot be detected.

The invention provides a wireless transmitting and receiving system for monitoring multiple neural signals. The wireless transmitting and receiving system comprises a central node and a plurality of terminal nodes, each terminal node is used for collecting a plurality of neural signals, detecting the transmission rate of each neural signal, performing narrowband modulation on the neural signal with the transmission rate smaller than a first threshold value to obtain a first radio-frequency signal, performing broadband modulation on the neural signal with the transmission rate larger than a second threshold value to obtain a second radio-frequency signal, and transmitting the second radio-frequency signal to the terminal node; sending the first radio frequency signal and the second radio frequency signal to a central node; the central node is used for acquiring a radio frequency signal, dividing the radio frequency signal into a broadband signal and a narrowband signal, demodulating the broadband signal to obtain first neural data, demodulating the narrowband signal to obtain second neural data, and sending the first neural data and the second neural data to the client. The method can support 16-order quadrature amplitude modulation and frequency shift keying modulation, and is suitable for long-time multi-target neural signal monitoring.

The present application relates to the technical field of industrial automation and fluid control, and particularly relates to a two-wire electromagnetic valve control system, comprising: a command compiling module, which acquires an externally input electromagnetic valve scheduling requirement and a target node address, and performs protocol encapsulation and cyclic redundancy calculation on the electromagnetic valve scheduling requirement and the target node address to construct a baseband control instruction set carrying a check feature. In the present application, a digital control sequence is converted into a frequency shift keying alternating current communication waveform and superimposed on a direct current bias voltage, coaxial and common rail multiplex transmission of communication control instructions and bottom layer driving electric energy on a two-wire physical medium is realized, while accurately positioning a target electromagnetic valve in combination with a node addressing mechanism, the number of field cable laying and construction complexity are reduced, and the overall deployment cost of an industrial field bottom layer control network is reduced.

The application relates to the technical field of pipeline detection, and discloses an anti-interference pipeline detection method and device, which comprises the following steps: acquiring a detection environment parameter, generating and transmitting a pipeline excitation signal through adaptive parameter selection and continuous phase frequency shift keying modulation; receiving an electromagnetic response signal in multiple channels, obtaining a digital signal through adaptive preprocessing; acquiring a digital code sequence through frequency shift keying demodulation, judging the signal effectiveness and outputting a quality score through correlation matching and reliability evaluation; based on the effective signal, solving pipeline position, buried depth parameters and uncertainty through multi-point fitting and model inversion; and adaptively optimizing system working parameters in combination with a detection performance index. The application can realize accurate detection and positioning of underground pipelines in a complex electromagnetic interference environment.

The embodiment of the invention provides a transceiver system of a very high frequency interphone, and the system comprises a main radio frequency board which is connected with a control board at one end and connected with a DSC radio frequency board at the other end, and is used for receiving an audio signal input by the control board and performing analog frequency modulation and frequency shift keying modulation on the audio signal to obtain a transmission signal; the integrated temperature and standing wave detection circuit is connected with the control panel and is used for monitoring the reflection power of the antenna port and the power amplifier temperature in real time and feeding back the reflection power and the power amplifier temperature to the control panel; the DSC radio frequency board and the main radio frequency board share an antenna port and are used for receiving and shaping the modulation signal to obtain a coded signal and outputting the coded signal to the control board; the DSC radio frequency board integrated power supply management module is used for generating multiple paths of power supplies by adopting a low-dropout linear regulator and carrying out graded power supply through the multiple paths of power supplies; and the control panel is used for adjusting the power in real time and carrying out audio decoding on the coded signal. Therefore, the anti-interference capability and the reliability are improved, the communication distance is farther, and the signal is clearer and more stable.

The application relates to a kind of unmanned cluster-oriented bionic compound eye wide-area sensing system, including coordinated light signal modulation and transmitting unit, wide-area bionic compound eye photoelectric sensing unit and spatial light communication and positioning calculation unit. Through the structural coding of control instruction and the use of frequency shift keying modulation, digital information is converted into near-infrared modulated light signal, realizing information space propagation; the receiving end uses bionic compound eye structure to realize wide-area field of view light signal convergence, and completes photoelectric conversion through spatial position sensor, combined with multi-channel signal processing to realize communication signal demodulation and feature extraction; on this basis, multi-dimensional features are constructed and spatial position is calculated, realizing the integration of information interaction and relative position perception between nodes. The application does not depend on radio frequency communication link and satellite navigation system, and can realize stable communication and cooperative sensing of unmanned cluster in complex electromagnetic countermeasure and navigation limited environment, with the advantages of strong anti-interference ability, good concealment and high environmental adaptability.

The invention discloses an instrument firmware upgrading method and device, an instrument and a storage medium. The method comprises the following steps: acquiring a flash memory data erasing instruction transmitted by a frequency shift keying (FSK) modulator, and erasing data of a target area in a flash memory based on the flash memory data erasing instruction; the flash memory data erasing instruction is determined by the FSK modulator based on a control instruction transmitted by a computer; the FSK modulator is connected with a sensor analog signal input interface of the instrument; acquiring an FSK firmware upgrading signal transmitted by the FSK modulator, wherein the FSK firmware upgrading signal is modulated, processed and determined by the FSK modulator based on a firmware upgrading file transmitted by the computer; and demodulating the FSK firmware upgrading signal to obtain a firmware upgrading file, storing the firmware upgrading file to the target area, and performing firmware upgrading through the firmware upgrading file. According to the scheme, the sensor analog signal input interface existing in the instrument is utilized, the instrument does not need to be disassembled for additional wiring or replaced, firmware in the instrument can be upgraded, cost is low, operation is easy, and practical operability is high.