213 results about "Bandwidth (signal processing)" patented technology

The measuring device comprises a computer used for data process, a signal process circuit connected to the computer, a pulse wave transmitting/receiving circuit connected to the signal processing circuit; a bandwidth transmitting/receiving transducer assembly connected to the pulse transmitting/receiving circuit. The data process program compares the measuring signal with the preset standard substance; the actually measured acoustic attenuation spectrum is combined with the acoustic attenuation spectrum obtained based on the scattering formula computational theory to construct the matrix and linear equation; using dual frequency attenuation ratioing to realize the calculation of average particle size; according to the particle size, inversely computes the particle concentration.

The invention provides a wideband digital frequency selecting pulling system, wherein a DAU diplexer in DAU, a DAU wideband digital downlink, a DAU photoelectric conversion subsystem, a DAU wideband digital uplink, and a DAU diplexer are connected in sequence; a DAU power subsystem and a DAU monitoring subsystem are respectively connected with the DAU wideband digital downlink and the DAU wideband digital uplink; the DRU photoelectric conversion subsystem in DRU, a DRU wideband digital uplink, a DRU diplexer, a DRU wideband digital downlink, and a DRU photoelectric conversion subsystem are connected in sequence; and a DRU monitoring subsystem and a DRU power subsystem are respectively connected with the DRU wideband digital uplink and the DRU wideband digital downlink. The invention also provides a signal processing method which is achieved by adopting the system. The invention can reduce the use of analog devices and realize the bandwidth digital frequency radiating pulling system with different bandwidth.

The invention relates to a signal reconstruction technical scheme for sampling with rate lower than nyquist rate. The signal reconstruction scheme comprises the following steps of: firstly, solving a transformation basic matrix (signals x to be reconstructed thereon are sparse on the transformation basic matrix), modulating the transformation basic matrix with a cutting sequence, filtering by means of a digital filter, sampling the filtered signals, then generating compressive sensing arithmetic operators, and finally obtaining reconstructed signals by solving an optimized problem through the sparse inverse transformation. The invention aims to provide the signal reconstruction technical scheme for sampling with rate lower than the Nyquist rate, satisfy the needs for people in solving the contradictions between the increasingly widening signal bandwidth as well as the increasingly quickening sampling frequency and the requirements for reducing processing time and various costs reduce the signal sampling frequency and data transmission and storage cost, further remarkably shorten the signal processing time and reduce the computational expense, and accurately reconstruct signals.

The invention discloses a photoinjection-type chaotic photonic integration device and a preparation method thereof. The photoinjection-type chaotic photonic integration device is characterized in that a principal distributed feedback semiconductor laser generates continuous wave laser, and the laser enters a passive waveguide after being amplified by a semiconductor optical amplifier, and then is injected into a subordinate distributed feedback semiconductor laser. Chaotic laser of a bandwidth can be generated by the subordinate distributed feedback semiconductor laser by adjusting the central wavelength between the semiconductor optical amplifier and the principal distributed feedback semiconductor laser as well as the subordinate distributed feedback semiconductor laser. According to the invention, photonic integration can be realized by injecting light into the semiconductor laser to generate the chaotic laser of the bandwidth, so that the chaotic laser performance is improved, the device size is greatly reduced, the stability of the system is improved, and the method has a simple process flow, is low in implementation cost, and has a broad application prospect in the future field of optical communication and photonic signal processing.

The invention relates to a device for measuring the arm length difference of a fiber optic interferometer, and mainly solves a problem that a measurement system employing an optical interference method is not high in stability and is low in measurement precision. The device provided by the invention comprises a narrow linewidth laser, a polarization-maintaining fiber coupler, a phase modulator, apolarization state controller, an acousto-optic frequency shifter, a fiber coupler, a to-be-tested fiber optic interferometer, a photoelectric detector, a frequency spectrograph, a signal processing and display module and a microwave signal generator. The device carries out the interference in microwave domain through a double optical frequency comb, and measures an interference signal by using the frequency spectrograph. The device can obtain the arm length difference of the to-be-tested fiber optic interferometer by the bandwidth of the interference signal in one cycle, and can achieve the measurement of the precision changes through changing the frequency interval of the optical frequency comb, thereby improving the measurement accuracy and the stability of the system, and ironing out the defect that a method employing optical interference cannot achieve the measurement of the arm length difference. The device is simple in workflow is simple and is high in generalizability.

The invention discloses a dual-wavelength superheterodyne-interference wide-range high-precision real-time displacement measuring system and method. The system is composed of two lasers between which the wavelength difference is deltalambda, three polarization splitting prisms, four splitting prisms, two acousto-optic modulators, four 1/4 waveplates, five planar mirrors, three Polaroids, a super-narrowband filter plate, two large-bandwidth transimpedance photoelectric detectors, two low-bandwidth high-sensitivity photoelectric detectors, a reference reflector, a measured reflector, a signal processing circuit and a host computer. According to the invention, a synthesized wavelength interference signal generated by dual wavelengths is used to improve the measuring range of the system, so that the measuring range of the system is greater than the range of single-wavelength interference; a superheterodyne interference method is used to demodulate and filter output signals, the phase of the synthesis wavelength can be measured directly, and real-time measurement is realized; and the super-narrowband filter plate is used to collect single-wavelength interference signals, and the precision of single-wavelength interference measurement is ensured while the measuring range is widened.

A signal acquisition system has a signal acquisition probe having probe tip circuitry coupled to a resistive center conductor signal cable with the signal cable coupled to a signal processing instrument via an input node. The input node is coupled to an input current amplifier via input circuitry. The input circuitry provides at least one of resistive and capacitive termination of the resistive center conductor signal cable. The termination of the resistive center conductor signal cable in the signal processing instrument provides a signal acquisition system where the capacitive loading of a device under test at higher frequencies is reduced by reducing the input capacitance of the probe tip circuitry resulting in an increase in the signal acquisition system bandwidth.

The invention belongs to the field of electronics, and discloses a digital downconverter with variable bandwidth. The digital downconverter comprises a path switching circuit, a narrow-band filter group and a wide-band filter, wherein the path switching circuit is used for selecting a proper processing path for signals in accordance with configuration of parameter configuration modules; the narrow-band filter group is used for processing input narrow-band signals based on the structure of the digital downconverter; and the wide-band filter is used for processing input wide-band signals or the output of the narrow-band filter group based on a multiphase filter structure. The invention also provides an implementation method of the digital downconverter with variable bandwidth. The digital downconverter with variable bandwidth integrates the advantages of a traditional digital downconverter structure with a single channel and the advantages of the multiphase filter structure into a whole, thus implementing high efficient and high-speed processing on input intermediate-frequency signals, and being capable of flexibly configuring signal processing bandwidth within a larger range.

The invention relates to the technical field of transient electromagnetic signal processing in geophysical exploration, and discloses a transient electromagnetic signal-to-noise separation method based on a variational mode decomposition principle, which is suitable for electromagnetic data filtering in a time domain. The method comprises the following steps: decomposing noisy transient electromagnetic data s(t) into K intrinsic mode functions uk(t); performing Hilbert transform on each intrinsic mode function to obtain a unilateral frequency spectrum; demodulating the frequency spectrum of each intrinsic mode function uk(t) to a corresponding base band according to the unilateral frequency spectrum, calculating a demodulated L2 norm, and calculating the bandwidth of the decomposed intrinsic mode function to obtain a constraint variation model; introducing a secondary penalty factor alpha and a Lagrange multiplication operator lambda, and converting the constraint variation model intoa non-constraint variation form; and calculating an optimal solution in a non-constraint variation form to obtain a series of optimized intrinsic mode components after VMD decomposition. The method solves the problem that transient electromagnetic data collected in geological interpretation is interfered by noise, is simple and convenient, has excellent noise separation and amplitude maintaining performance, can extract noise images, and provides conditions for subsequent noise analysis.

The invention discloses a method for processing a broadcasting signal in a conditional access system in a broadcasting field as well as a system and a receiving terminal thereof, which is used for sending signals to a plurality of terminal broadcasts through a narrow band by a sender, which comprises the steps: the signal is sent after scrambled by the sender; a scrambling control word is encrypted; encrypted information which contains the encrypted scrambling control word is sent and the encrypted information is the same information; after the scrambling control word is decrypted by the terminal according to a key for decrypting selected according to the encrypted information, the scrambling control word is used for descrambling the received signal. By using the method for processing the broadcasting signal in the conditional access system in the broadcasting field as well as the system and the receiving terminal thereof, the conditional access in the narrow-band broadcasting system can be realized, which solves the problem that large bandwidth is required to be occupied for authorizing the control information to be related with the user in the prior conditional access way; existing weakness that data flow is easy to be monitored can be eliminated; the operation of user management is flexible and convenient and at the same time a good protection effect is brought into play for the user and the broadcasting system operator.

The invention provides a SPR neural synaptic device based on a-SiOx memristor effect and a preparation method thereof, belonging to the technical field of biomimetic devices. The invention combines K9glass prism with 'top electrode/a-SiOx: metal nanoparticle double resistive layer/bottom electrode' memristor structure coupling, so the optical signal is allowed to be injected into the double resistive layer through the K9 glass prism under the electric modulation, A surface plasmon resonance (SPR) effect is utilize to read that dielectric constant change information of the resistive layer during the working process of the device, thereby realizing the optical read of the synaptic weight of the device. The 'electrically modulated, optically read' synaptic device of the invention has the advantages that the traditional 'electrically modulated, electrically read' synaptic device cannot be compared with, because the synaptic device not only has the characteristics of low energy consumptionand non-volatility of the traditional memristor, but also has the advantages of large signal processing bandwidth and strong electromagnetic interference resistance when the light is used as an information carrier.

The present invention is a signal processing method for use in a CDMA adaptive array antenna system, the method for forming the beam pattern by maximizing a transceiving gain in a direction toward a target mobile station and optimizing the beam pattern in a moving direction depended on a moving direction of each target mobile station during signal transceiving between a base station and the mobile station, the method forming an ideal beam pattern by a simplified computation procedure, and a computer readable recording medium for storing a program for implementing the method. The method comprises determining signature of gradient of output power of the array antenna to the phase of each antenna, updating the phase of each antenna by increasing or decreasing the phase by an adaptive gain depending on the signature of the corresponding gradient, determining weight corresponding to the updated phase, and applying the weight to a signal arrived at each antenna. The present invention increases significantly communication capability per cell and improve communication quality for a given bandwidth.

The invention belongs to the field of optical signal processing and the field of sensing, and relates to a high-sensitivity ultrasonic detection method based on a digital optical frequency comb and amicrocavity array. An advanced signal processing technology in the field of optical communication is utilized to obtain a digital optical frequency comb signal with a certain bandwidth, and the digital optical frequency comb signal is utilized to scan a micro-cavity photonic device to obtain an ultrafast and high-precision micro-cavity resonance peak scanning spectral line. Meanwhile, only one light path system is required to be coupled with the plurality of micro-cavity structures, so that the equal-interval wavelength distribution of the resonance peaks of the plurality of micro-cavities isrealized. Wavelength positions of resonance peaks of a plurality of micro-cavities are designed; rapid and high-precision detection of the frequency and the power of respective resonance peaks of thelarge number of micro-cavity structures by the digital optical frequency comb can be realized; the efficiency and the processing difficulty of ultrasonic array detection can be remarkably improved; the method can be applied to the fields of ultrasonic array detection, photoacoustic imaging and the like; and meanwhile, a basis is provided for research of an integrated and miniaturized ultrasonic phased array detector.

The invention belongs to the array signal technology, and relates to a method of equalizing unmatched channels in a certain bandwidth. The channel equalization method comprises the following steps: 1, a frequency domain equalization filter is converted into an N-point filter, and N is selected to be the least power no smaller than L, and the N-point frequency feature e<N><O> of the frequency domain equalization filter is solved; 2, each section filter coefficient for segmented equalization is solved; and 3, the eN is used for carrying out equalization processing on a baseband complex signal xA of the to-be-equalized channel, and a complex signal sequence xAE after equalization is obtained. The storage space needed by channel equalization can be reduced, the cancellation performance between channels is improved, the array processing performance is thus enhanced, and requirements of multichannel array signal processing by a modern communication system, a phased array radar system and the like can be met.

The key of the general and high speed waveguide wavelength scan demodulating method is to apply periodical scanning voltage signal on a tunable waveguide filter to make the reflected wavelength vary periodically and to realize the scan of spectrum. The initial reflection wavelength, bandwidth, reflectivity and other parameters of the tunable waveguide filter are designed based on the required light source wavelength and demodulation precision of the demodulator; and the filter wavelength scanning range, scanning frequency and other parameters are controlled through altering the amplitude andfrequency of the driving electric signal for the modulator. The equipment consists of light source, fiber optical path, tunable waveguide filter, which comprises single-mode light waveguide, Bragg grating and modulator, and detecting and signal processing device with intelligent distinguish function.

The invention discloses an integrated structure of a coherent channelized receiver. The integrated structure comprises a laser generation module, a first optical frequency comb generation module, a second optical frequency comb generation module, a suppression carrier single sideband modulation module, an I/Q optical mixing module, two parallel optical filter modules and a plurality of I/Q electric coupling modules. According to the invention, the microwave photon technology is utilized, and compared with the traditional channelization equipment utilizing electric signal processing, the structure can reduce the radio frequency interference; by utilizing a single sideband modulation mode of inhibiting carrier waves, the processable bandwidth is improved, symmetrical mirror image componentsgenerated by interaction of signals and original carrier waves are prevented from being generated, the requirement on an optical band-pass filter is reduced, the integration of an optical filter is facilitated, and meanwhile, the signal to noise ratio of output signals is improved. According to the invention, the structure of the carrier suppression single-sideband modulator is optimized, the sizeis reduced, and the precision is improved; through the integration of the main body optical path, the volume of the receiver is reduced, and the practicability and reliability of the channelized receiver are improved.

The invention discloses an efficient pre-distortion method for a 100MHz signal bandwidth power amplifier, and belongs to the technical field of wireless communication. According to the pre-distortion method, only part of output signals of a power amplifier (PA) are subjected to linear compensation, and a multi-phase DPD structure is adopted; an intelligent signal processing module is added in a digital pre-distortion system, the intelligent signal processing module sets the number of half-band filters according to a to-be-compensated DPD linearization bandwidth, calculates ADC undersampling factors and the number of multi-phase DPD branches in combination with source signal parameters, and performs correlation calculation on an undersampling signal and an output signal of the DPD to obtain time delay; therefore, alignment of two data signals during parameter training is ensured. According to the invention, the DPD data throughput and the feedback loop sampling bandwidth can be reduced in a linkage manner at the same time, the DPD data throughput can be flexibly set, and the hardware implementation cost of the DPD is saved.

The invention discloses a microwave photon broadband receiver which is characterized in that 2n frequency multiplication modulation is carried out on an optical carrier outputted by a laser through afirst photoelectric modulator, the frequency of a modulation signal is 1/2n of that of a microwave local oscillator signal omega L, and a pair of optical local oscillators with the frequency difference of omega L is obtained through filtering processing of an optical wave trap; a radio frequency signal omega RF received by the antenna is modulated to the optical local oscillator through the secondphotoelectric modulator after passing through the low-noise amplifier, and then enters the photoelectric detector to be converted into an intermediate frequency electric signal omega IF after being processed by the optical filter; a medium-frequency band-pass filter is used for further filtering, and digital signal processing is carried out in an acquisition processing module. Down-conversion receiving processing of cross-band ultra-wideband microwave signals can be achieved, meanwhile, the requirements for large bandwidth, ultra-flexibility, soft programmable control and the like are met, and wide application prospects are achieved in the fields of high-speed communication and radar electronic countermeasures in the future.

The embodiment of the invention provides a signal processing circuit and method and electronic equipment, and the circuit comprises a radio frequency chip, a power amplifier, a filter, and a tuning assembly, wherein the first end of the radio frequency chip is connected with the first end of the power amplifier, the second end of the power amplifier is connected with the first end of the tuning assembly, the second end of the tuning assembly is connected with the first end of the filter, and the second end of the filter is connected with a radio frequency antenna; the third end of the tuning assembly is connected with the control end of the radio frequency chip, the tuning assembly has N working states, the impedance values of the tuning assembly in different working states are different,and N is greater than or equal to 2; under the condition that the frequency of the radio frequency signal generated by the radio frequency chip is within the target bandwidth range, the radio frequency chip controls the tuning assembly to work in a target working state associated with the target bandwidth range. According to the embodiment of the invention, the consistency of radio frequency signals transmitted by the signal processing circuit can be improved, and the debugging complexity of the signal processing circuit is reduced.

The invention discloses an SRIO switching system which is characterized by comprising a PowerPC microprocessor, a RapidIO switching chip and a peripheral circuit, wherein the RapidIO switching chip isinterconnected with the PowerPC microprocessor by a high-speed SerDes interface and implements a single-path configurable transmission rate of 1.25, 2.5, 3.125, 5.0 and 6.25Gbaud; when five switchingchips are combined, 48 paths of serial channels in total and a maximum internal switching bandwidth of 240Gbps are implemented; the PowerPC microprocessor converts an electric signal into an opticalfiber signal by a photoelectric conversion module to implement data switching with the outside of the switching system; and the peripheral circuit comprises a power supply module, a clock module, a reset module and an interrupt management logic module. According to the invention, high-capacity data switching is implemented, so that data switching between a front-end preprocessing unit of a task electronic system and signal processing unit equipment can be met.

The invention discloses a chirp laser radar fusion ranging method based on a Kalman filtering algorithm. A laser radar in the present invention adopts a field programmable gate array (FPGA) to controla digital frequency synthesizer (DDS) to generate a continuous linear frequency modulation signal for transmitting laser modulation, the frequency mixing signals are collected through a high-speed ADC, and the distance and radial speed information of a target is extracted in real time through a digital signal processing module. A system adopts the linear frequency modulation laser with the bandwidth of 120MHz and the period of 90mus to perform coherent ranging in a heterodyne ranging mode, and the precision of coherent ranging reaches 1.373 m, and in a homodyne speed measurement mode, adoptsthe single-frequency laser of 200 MHz for coherent speed measurement, and the coherent speed measurement precision reaches 0.00946 m/s. On the premise of not increasing the power consumption of the system, the Kalman filtering algorithm is adopted to perform real-time data fusion on the target information to obtain the continuous high-precision distance measurement information, the distance measurement precision of the system is improved by more than one order of magnitude, and the accuracy of the laser coherent distance measurement is improved.