1174 results about "Phase noise" patented technology

The invention relates to the technical field of semiconductors, and discloses a full-temperature-zone polynomial digital temperature compensation method and system based on an SOI chip, and the method comprises the steps: obtaining the temperature frequency data of a preset temperature zone of a target SOI chip, fitting a full-temperature-zone curve, extracting a critical point of the temperature zone, dividing a segmented compensation interval according to the critical point, and obtaining the temperature frequency data of the preset temperature zone of the target SOI chip; the method comprises the following steps: calculating frequency drift amounts under different voltages to construct a full-automatic test framework, acquiring an environment temperature parameter and an instantaneous temperature value by using the framework, analyzing a temperature compensation vector of a segmented compensation interval, further monitoring a signal frequency interval output by a chip, extracting a phase noise parameter, calculating a frequency offset error amount with a preset value, and calculating the frequency offset error amount. And analyzing an error source, optimizing a polynomial compensation order, and collecting temperature drift suppression data to generate a full temperature region compensation report. According to the invention, the performance stability of the chip in a complex environment can be improved.

The invention belongs to the technical field of distributed optical fiber sensing, and particularly relates to an OFDR system phase noise compensation device and method based on an or equivalent optical fiber loop auxiliary interferometer. The optical fiber 2 * 2 coupler and the delay optical fiber form a loop and serve as a delay optical path of the auxiliary interferometer, the optical delay can be doubled every time laser passes through the loop, and therefore a plurality of beat frequency signals with different optical delays are obtained. And according to the to-be-measured optical fibers at different distances on the main interferometer, the beat frequency signal of the auxiliary interferometer with the closest optical delay is selected for compensation. And splicing the compensated reflected signals at different distances to obtain a distance domain reflected signal of the whole sensing optical fiber, thereby realizing phase noise compensation in the full range of the OFDR system. The OFDR full-range high-precision measurement is realized, and the OFDR full-range high-precision measurement device has the characteristics of simple structure, stable performance, low manufacturing cost and the like.

The invention discloses an intelligent target distribution method and system for collaborative interception, particularly relates to the field of radar networking, is used for solving the problem of correction of phase noise accumulation and array error propagation, and comprises the following steps: establishing a high-dimensional node phase distribution model, determining a noise mode and extracting key features; in combination with calculation of a phase drift index and a signal distortion index and construction of a multi-dimensional noise matrix, fine quantization of node errors is realized; on the basis, the array surface information is corrected in real time by using a dynamic interpolation and phase offset correction technology, node cooperation is optimized in combination with an energy measurement algorithm, and the stability and precision of the array surface information are improved; and finally, through a multi-dimensional decision matrix, target features and node states are comprehensively analyzed, and intelligent allocation and optimization of resources are realized. Therefore, the observation precision and the cooperation efficiency of radar networking are remarkably improved, and reliable technical support is provided for high-precision target monitoring and resource optimization allocation in a complex environment.

The invention provides a clock signal generating circuit, a wired communication transceiver and electronic equipment, and the circuit outputs a first DC voltage comprising phase difference information and frequency difference information of a reference clock signal and a feedback clock signal through a phase frequency detection module. The pulse generator generates a narrow pulse signal based on the DC voltage and a reference clock signal, the oscillation frequency of each secondary ring oscillator in the cross-coupled ring oscillator is controlled by the first DC voltage, and the cross-coupled loop performs synchronous coupling and phase sequence adjustment processing on each secondary ring oscillator. One output node in the cross coupling ring oscillator receives the narrow pulse signal, frequency and phase locking is completed in an injection locking mode, and the frequency divider is used for conducting frequency division processing on any high-frequency clock signal and outputting a feedback clock signal. Therefore, a high-frequency multi-phase clock signal with low phase noise and high phase precision can be generated by using the low-frequency reference clock signal.

The invention provides a broadband tunable low-phase-noise photo-generated microwave signal source and device, and relates to the technical field of photo-generated microwaves. According to the invention, a low-frequency optical pulse and a high-frequency microwave signal are respectively input into the electro-optical sampling phase-locked loop; and the electro-optical sampling phase-locked loop determines the synchronization error of the optical pulse and the microwave signal based on the phase difference between the optical pulse center point and the microwave signal zero crossing point. And taking the synchronization error as a feedback signal, and continuously adjusting the frequency and the phase of the microwave signal by the voltage-controlled oscillation module until the frequency and the phase are synchronized with the Nth harmonic of the optical pulse. By setting different initial frequencies of the voltage-controlled oscillation module, microwave signals with different integral multiple optical pulse frequencies can be obtained, and broadband tuning of photo-generated microwave signals is realized. Furthermore, the repetition frequency of the frequency comb is locked through beat frequency of two beams of reference laser and two adjacent comb teeth, the stability of the reference laser is transmitted to the optical pulse, and the stability of the reference laser is further transmitted to the microwave signal through synchronization of the optical pulse and the microwave signal, so that the phase noise of the photo-generated microwave signal source is reduced.

The invention discloses an ultra-low phase noise harmonic wave type four-core voltage-controlled oscillator. The ultra-low phase noise harmonic wave type four-core voltage-controlled oscillator is composed of a transformer T1, a transformer T2, a transformer T3, a transformer T4, a head oscillator HR1, a head oscillator HR2, a head oscillator HR3, a head oscillator HR4, a resistor R1, a resistor R2, a resistor R3, a resistor R4 and a plurality of decoupling capacitors Cecap. According to the voltage-controlled oscillator, noise is prevented from being converted into phase noise by means of second and third harmonic impedance broadening, inductance loss reduction, reduction of the sensitive time of the resonant cavity to the noise and the like, the phase noise generated by the voltage-controlled oscillator can be effectively reduced, and excellent noise performance is obtained.

The invention provides a resonator phase noise suppression method based on Kalman filtering. The resonator phase noise suppression method comprises the following implementation steps: sampling displacement of a resonator; calculating a priori error matrix and a priori estimation value of each sampling; calculating the Kalman gain of each sampling; calculating an error matrix of each sampling; and obtaining a resonator phase noise suppression result. According to the method, suppression of the resonator phase noise in the mechanical resonant device is realized based on Kalman filtering, and the method is suitable for various noise types including high-frequency noise, can flexibly cope with different working environments and noise types, and has relatively good adaptability; based on the recursive calculation characteristic of Kalman filtering, state estimation can be updated every time new data arrives, processing of all historical data is not needed, meanwhile, dynamic estimation and optimization are carried out on input signals in combination with a prediction model and noise observation, a filter can rapidly respond to the change of signal frequency, and the accuracy and the reliability of the method are improved. And an efficient real-time adjustment capability is provided.

The invention relates to the technical field of machine learning, and discloses a radio measurement calibration method and system based on machine learning, and the method comprises the steps: carrying out the parameter measurement of a radio signal source, and obtaining an original measurement data set; based on the original measurement data set, extracting a frequency precision feature, a power flatness feature, a phase noise feature, a harmonic ratio feature and an environment change feature to obtain a feature data set; dividing the feature data set into a training data subset, a verification data subset and a test data subset, and constructing a first neural network model containing a double-branch neural network based on the training data subset; and inputting the verification data subset into the first neural network model for model parameter optimization to obtain a second neural network model, thereby improving the calculation precision of calibration parameters and the accuracy of environment compensation.

The invention discloses an ultra-low phase noise microwave signal generation method and system based on an electro-optical comb. The method comprises the following steps: 1) locking two lasers with continuously tunable wavelengths in the same FP cavity through two links with different modulation frequencies to realize a dual-wavelength laser with a frequency interval of (v2-v1); 2) reducing the electronic noise of each link to a quantum noise limit by using a residual amplitude modulation noise control technology; 3) coupling the lasers with the center frequencies of v1 and v2 into one path, inputting the laser into an electro-optical frequency comb generator, and generating two sets of electro-optical frequency combs with spectrum overlapping; (4) beat frequency signals of the two electro-optical frequency combs are obtained; the beat frequency signal and a reference signal from a reference signal source are accessed to a phase discriminator for phase discrimination; an output signal of the phase discriminator is sent to a proportional-integral-differential control circuit; and 5) controlling the phase noise of the radio frequency source by using the output feedback of the proportional-integral-differential control circuit to obtain an ultra-low phase noise microwave signal.

Millimeter wave (mmWave) technology, apparatuses, and methods that relate to transceivers, receivers, and antenna structures for wireless communications are described. The various aspects include co-located millimeter wave (mmWave) and near-field communication (NFC) antennas, scalable phased array radio transceiver architecture (SPARTA), phased array distributed communication system with MIMO support and phase noise synchronization over a single coax cable, communicating RF signals over cable (RFoC) in a distributed phased array communication system, clock noise leakage reduction, IF-to-RF companion chip for backwards and forwards compatibility and modularity, on-package matching networks, 5G scalable receiver (Rx) architecture, among others.

The invention discloses a method for estimating the transmittance of a time-varying channel based on a frequency division multiplexing pilot frequency, and aims to solve the problem that the existing method for estimating the transmittance by adopting average transmittance does not have the capabilities of timely feedback and dynamic adjustment. The method comprises the following steps of: measuring a regular position component and a regular momentum component of a received signal by receiving a quantum signal and a pilot signal of frequency division multiplexing in a local local oscillator continuous variable quantum key distribution system generated by a transmitting end in real time; compensating phase noise caused by frequency offset and channel jitter due to different center frequencies of two independent lasers at a receiving end and a transmitting end by using a frequency offset compensation and phase recovery algorithm, and performing band-pass filtering to obtain a recovered pilot signal; and calculating the power ratio of the obtained pilot signal to the pre-calibrated pilot signal at each moment to obtain the time-varying free space transmittance. The performance change of the system in different time periods can be accurately reflected, the communication performance of the CVQKD system can be optimized, the success rate of key transmission can be improved, and the adaptability and robustness of the system can be improved.

The invention discloses a frequency source synthesis system and method based on a frequency agility radar, and belongs to the technical field of microwave radio frequency, and the method specifically comprises the steps: generating a target clock signal, carrying out the frequency processing of the target clock signal to generate a frequency multiplication signal, and dividing the frequency multiplication signal into two clock signals through a power divider; performing frequency multiplication processing on one path of clock signal, taking the processed signal as a clock reference signal of a direct digital synthesizer, generating an analog signal according to the clock reference signal, and calibrating the analog signal as an output signal; performing frequency multiplication processing on the other path of clock signal, and taking the processed clock signal as a local oscillation signal of the frequency mixer; performing frequency conversion processing to obtain a frequency mixing signal, performing quadruplicated frequency processing on the frequency mixing signal, and calibrating the processed frequency mixing signal as a final output signal; according to the invention, the frequency source has the characteristics of low phase noise, rapid agility, fine resolution and miniaturization at the same time.

The invention discloses a low-phase noise ring voltage-controlled oscillator based on multiphase injection locking, relates to the technical field of integrated circuits, and is used for solving the technical problems that an existing injection locking oscillator limits the frequency tuning range and cannot effectively suppress noise. The invention discloses a low-phase noise ring voltage-controlled oscillator based on multiphase injection locking. The low-phase noise ring voltage-controlled oscillator comprises a first ring oscillator unit and a second ring oscillator unit, the n first ring oscillator units are connected in series to form a chain structure; the second ring oscillator unit is provided with a cross coupling inverter complementary injection unit and a tail current source injection unit; a first output end of the chain structure is connected with a second input end of the second ring oscillator unit, and a second output end of the chain structure is connected with a first input end of the second ring oscillator unit; a first signal is injected into a cross-coupling inverter complementary injection unit and a tail current source injection unit, and a second ring oscillator unit receives a second signal output by a chain structure and then outputs a third signal.

The invention discloses an emergency command system and method based on satellite communication, and particularly relates to the technical field of radio transmission. On-site information of a disaster area is obtained in real time, the information is transmitted to an emergency command center through a satellite communication channel, dynamic command decision and resource optimization are achieved, in the signal transmission process of the system, the phase noise and the inter-carrier interference ratio of satellite signals are monitored and analyzed in real time, whether the signals are distorted or not is judged, and when the signals are distorted, the emergency command center is started. The system is automatically switched to a standby satellite communication channel to ensure that information transmission is not interrupted; besides, the satellite communication link monitoring system can adjust the signal quality in real time and carry out fault-tolerant processing, continuous operation of the command system is ensured, emergency response failure caused by communication interruption is avoided, the stability of satellite signals in various environments is effectively improved, and efficient operation of the emergency command system is ensured.

The invention provides a differential InSAR system, method and application and a readable storage medium. The system comprises a laser emission module, a radar detection module and a self-adaptive optical compensation module. The laser emission module supplies energy to the system and splits light; the radar detection module cooperatively detects a target by means of two symmetrical branches, and acquires and processes echoes to achieve the purpose of differential detection. The adaptive optical compensation module corrects laser wavefront distortion caused by atmospheric turbulence in real time according to deep learning and a wavefront detection mechanism, and ensures accuracy and stability of long-distance remote sensing. The method is characterized in that the adaptive optical performance is improved by combining deep learning, and phase noise is suppressed. The method has far-reaching significance in the fields of topographic mapping, geological disaster monitoring and the like, and can accurately measure the topographic elevation and the ground surface infinitesimal displacement, for example, the early millimeter-level variation is sensitively captured in the landslide early warning, and the opportunity is robbed for disaster prevention and control.

A PTRS sending method and receiving method and a communication apparatus. The method includes: a terminal device sends first information to a network device, receives first indication information from the network device, and sends a DFT-s-OFDM symbol to which a PTRS is mapped to the network device. In the method, a rule for mapping the PTRS to a plurality of layers of the DFT-s-OFDM symbol is specified, to ensure phase noise estimation performance and improve a demodulation capability.

The invention discloses a noise suppression parameter self-adjusting optical fiber optical frequency transfer relay system, which comprises multiple stages of relay stations which are cascaded in sequence, each stage of relay station comprises a receiving end, an optical amplification end and a transmitting end which are connected in sequence, and the transmitting end of the previous stage of relay station is connected to the receiving end of the next stage of relay station, the receiving end is used for receiving an optical frequency signal from an upper-level relay station; the optical amplification end is used for carrying out coherent amplification on a received optical frequency signal, and the sending end is used for transmitting the optical frequency signal after coherent amplification to a next-stage relay station and measuring and eliminating additional phase noise in a signal transmission link. According to the optical fiber optical frequency transfer relay system, self-adjustment of noise suppression parameters can be effectively achieved, and therefore effective suppression of additional phase noise is achieved.

A low-phase noise class-D voltage-controlled oscillator based on a broadband harmonic shaping technology comprises a head resonance unit, an LC resonance unit composed of a first inductance unit, a second inductance unit and a first capacitance unit, a negative resistance unit, a variable capacitance unit, an array capacitance unit and an output unit. The output end of the head resonance unit is connected with one end of the first inductance unit, the other end of the first inductance unit is connected with one end of the negative resistance unit, the other end of the negative resistance unit is connected with the first capacitor unit, the first capacitor unit is connected with the variable capacitor unit, and the variable capacitor unit is connected with one end of the array capacitor unit. The other end of the array capacitor unit is connected with one end of the second inductor unit, the other end of the second inductor unit is grounded, two input ends of the output unit are connected with the variable capacitor unit, and two output ends of the output unit serve as output ports of the voltage-controlled oscillator.

The invention provides a multi-phase clock generator which outputs N injection current signals corresponding to different phases by processing an input clock signal, N is an integral multiple of 4, and a cross-coupled loop is arranged in a cross-coupled ring oscillator. The loop is respectively coupled with output nodes in N / 4 secondary ring oscillators based on a phase sequence, and the secondary ring oscillators realize high-working-frequency and high-stability oscillation frequency output and low-error phase alignment through a cross coupling mechanism, so that the secondary ring oscillators can output N oscillation clock signals with equally-spaced phases, and the phase alignment is realized. Since the injection current signal is input into each output node in the secondary ring oscillator based on the phase sequence, the frequency and the phase of the secondary ring oscillator are locked, the frequency is the same as the frequency of the input clock signal, and the phase noise is very low, so that the frequency and the phase of the secondary ring oscillator are locked. According to the invention, a high-speed multi-phase clock signal with low phase noise and high phase precision can be generated.

The invention relates to the technical field of communication, and discloses a network communication chip signal interference suppression processing method. The method comprises the following steps: acquiring a local oscillator phase jitter sequence in real time through an on-chip phase noise monitoring unit; estimating Doppler frequency shift and channel coherence time based on the sequence; dynamically adjusting the closed-loop bandwidth of the phase-locked loop; and generating a phase compensation signal, and performing time-varying channel minimum mean square error equalization in combination with a received baseband signal to eliminate inter-symbol interference. The system integrates a phase noise monitoring function module, a channel parameter estimation function module, a phase-locked loop bandwidth regulation function module, a phase compensation generation function module and an interference joint elimination function module. By means of dynamic bandwidth reconstruction and high-precision phase compensation, the bit error rate under high-speed movement is remarkably reduced, the 5G millimeter wave communication standard requirement is met, and the method has the advantages of being achieved on a whole chip, low in delay and high in robustness.

A satellite tracking channel has a frequency loop tracking a carrier frequency of a satellite signal. A first indication of a spoofed signals is generated based on a determined satellite signal noise floor value associated with the satellite tracking channel and a tracking channel signal noise threshold associated with the satellite tracking channel. A second indication of a spoofed signal is generated based on a determining satellite tracking phase noise associated with the satellite tracking channel and a tracking channel phase noise threshold associated with the satellite tracking channel. Reception of a spoofed signal on the satellite tracking channel is detected based on the generated first indication of a spoofed signal and the generated second indication of the spoofed signal.

The invention relates to a glacier ice reserve estimation method based on a flight type ice measuring radar. The method comprises the following steps: acquiring a large-range terrain of a glacier; emitting microwaves for measuring the ice thickness in the glacier boundary; receiving echoes for measuring the ice thickness in the glacier boundary; positioning the acquired microwave signals in real time; processing ice thickness data; and estimating the glacier reserves. In order to improve the glacier detection accuracy, the core equipment glacier thickness measuring radar has centimeter-level ice layer distinguishing capability and five hundred-meter-level ice thickness penetrating capability, has the characteristics of light weight, miniaturization, high reliability and the like, is suitable for high-cold and high-altitude conditions, and is suitable for being carried by an unmanned aerial vehicle platform. Through the ultra-wideband high-stability low-phase noise signal generation technology, the weak echo signal receiving technology, the ultra-wideband antenna technology and the like, the thickness measuring radar system has the effects of light weight, miniaturization, high reliability and the like. The unmanned aerial vehicle is suitable for climatic conditions such as high glacier altitude and thin air, the defect that manual arrival or pull-type measurement must be relied on is overcome, and the testing efficiency is improved.

A dual path PLL provides excellent output phase stability over PVT variations, without implementing a high accuracy TDC. A digital integral path employs a binary phase detector, comparing the reference and feedback signals, and an integrator to generate an oscillator control input to lock the long-term output phase to the reference signal. An analog proportional path employs a linear (e.g., edge triggered) phase detector and a charge pump and filter to generate an oscillator control input to mitigate phase noise in the output signal. The feedback signal to the proportional path is delayed, which has the effect of increasing the width of phase error pulses, and moving the charge pump operating point away from the zero point where it generates both positive and negative currents, which are difficult to match. A second linear phase detector in the proportional path compensates for the increased phase error pulse width by comparing the delayed and non-delayed feedback signals, and generating pulses in the opposite direction.

A measurement system comprising circuitry configured to determine a phase noise cancelled speed measurement (SPD) based on interference of a chirping upper single sideband (CUSB) and a fiber delay reference (FDR) and based on interference of a chirping lower single sideband (CLSB) and the fiber delay reference (FDR).

The invention belongs to the technical field of quantum security communication, and discloses a phase noise-based miniaturized quantum random number generator, the generator comprises a space quantum entropy source module and an electronics module, the space quantum entropy source module comprises two lasers, two half-wave plates, three polarization beam splitters, two rectangular prisms and two photoelectric detectors; the electronics module comprises an analog-to-digital converter used for collecting electric signals and generating initial random bits. And the post-processing module is used for processing the initial random bits and generating true random numbers. Compared with the prior art, polarization interference between different components of the two lasers is achieved through random phase fluctuation between the two independent lasers and a basic structure formed by the three polarization beam splitters, multi-path output can be conducted through spatial multiplexing, and therefore the random number generation rate can be increased exponentially; and by adopting a device with a small blocky crystal structure, miniaturization integration can be realized, and the reliability and the stability are improved.

The invention discloses a low-cost broadband direct synthesis type frequency source, belongs to the technical field of radar communication, and mainly solves the problem that a traditional direct synthesis type frequency source cannot simultaneously realize low phase noise, short frequency hopping time and low cost. The frequency source comprises a harmonic generation circuit, a power division circuit connected with the harmonic generation circuit, a switch matrix connected with the power division circuit, and a frequency mixing synthesis circuit connected with the switch matrix. Wherein the harmonic generation circuit is used for generating a harmonic signal, the power division circuit is used for dividing the harmonic signal into six paths, and the switch matrix is used for outputting two paths of 12-17GHz signals from the power-divided signals. Compared with the traditional direct synthesis type frequency source, the direct synthesis type frequency source disclosed by the invention has the advantages that one harmonic generator and one switch filter group are omitted, so that the direct synthesis type frequency source disclosed by the invention realizes a low-cost broadband direct synthesis type frequency source.

Embodiments of this application disclose a noise cancellation apparatus and method. The noise cancellation apparatus includes a main control unit and a noise cancellation processing circuit. The main control unit determines a noise cancellation parameter based on a noise cancellation level index or a feature value for determining a matching degree between a headset and an ear canal of a user. The noise cancellation processing unit obtains an inverse phase noise of an ambient noise based on the noise cancellation parameter. After the inverse phase noise is mixed with a played downlink audio signal, the ambient noise can be canceled. In addition, because the noise cancellation parameter is determined from a preset noise cancellation parameter library based on the received or autonomously determined noise cancellation level index, instead of being uniformly configured, a noise cancellation level can be flexibly adjusted.

The invention relates to a double-loop phase-locked low-phase-noise reference local oscillator circuit structure which comprises a first phase-locked loop, a first signal processing unit, a power distribution circuit, a second phase-locked loop, a second signal processing unit and a frequency multiplication unit. The output end of the first phase-locked loop is connected with the input end of the first signal processing unit, the output end of the first signal processing unit is connected with the input end of the power distribution circuit, the output end of the power distribution circuit is connected with the input end of the second phase-locked loop, and the output end of the second signal processing unit outputs local oscillator signals through the frequency multiplication unit in sequence. By adopting the double-loop phase-locked low-phase-noise reference local oscillator circuit structure, various reference local oscillator signals can be output at the same time to be provided for the whole system to use through the circuit structure of the multi-path phase-locked loop. By changing the second phase-locked loop, better phase noise than broadband VCO and DDS can be obtained.

The invention relates to the technical field of optical communication, and discloses a multi-dimensional and multi-phase-based 50G PON signal noise compensation method, which comprises the following steps: S1, generating a mixed signal, including superposing a multi-phase orthogonal pilot signal into a data signal time domain at a transmitting end according to a preset proportion lower than the power of a data signal; and S2, transmitting the mixed signal in a polarization multiplexing mode, wherein the polarization multiplexing adopts double-channel parallel transmission of an X polarization state and a Y polarization state. Multi-phase orthogonal pilot signals are superposed to a data signal time domain in a low-power proportion at a transmitting end, polarization multiplexing dual-channel transmission is adopted, a narrow-band filter is utilized at a receiving end to separate pilots and calculate channel damage parameters, and a finite impulse response filter is configured to perform linear equalization compensation. And the simplified Kalman filtering algorithm is combined to estimate the phase noise and correct the phase, so that collaborative suppression of the linear channel damage and the phase noise in the 50G PON signal is facilitated.

The invention discloses a cloud wireless access network millimeter wave signal optimization method based on machine learning, which adopts a double-ring OEO to replace a traditional radio frequency signal source, improves phase noise and improves signal stability. Meanwhile, the gain behavior of the millimeter wave signal is modeled by using a BiLSTM network, and high-precision power prediction is realized by combining the DML chirp effect and the influence of optical fiber dispersion. Besides, the BiLSTM model is optimized through the ACO algorithm, the optimization weight can be flexibly adjusted according to different communication scene requirements, and millimeter wave signals meeting the requirements are generated.