219results about "Carrier regulation" patented technology

The invention discloses a Doppler frequency offset estimation method and electronic equipment, and relates to the technical field of communication, and the method comprises the step that the electronic equipment communicates with a low-orbit satellite in a discontinuous reception (DRX) mode. Wherein in a discontinuous reception (DRX) mode, the electronic equipment enters a wake-up period when the wake-up moment arrives, the electronic equipment communicates with a low-orbit satellite in the wake-up period, the electronic equipment enters a sleep period when the sleep moment arrives, and the electronic equipment stops communicating with the low-orbit satellite in the sleep period. When the wake-up moment arrives, the electronic device obtains at least one historical Doppler frequency offset value; and the electronic equipment determines a Doppler frequency offset value corresponding to the wake-up moment based on the historical Doppler frequency offset value. In the scheme, the Doppler frequency offset value at the wake-up moment is estimated through the historical Doppler frequency offset value, and the electronic equipment can calculate the Doppler frequency offset value at the current wake-up moment, so that frequency offset compensation can be carried out in time at the current wake-up moment, and the performance of frequency offset compensation is optimized.

The invention relates to the technical field of semiconductor radio frequency signal processing, and discloses a narrowband signal receiving system and method, and the system comprises a coarse frequency offset value capturing module, a carrier phase locking module, a digital domain carrier tracking module, a timing synchronization and multipath correction module, and a vector amplitude phase correction and equalization module. In the prior art, the technical problems of lock losing, judgment errors and high bit error rate caused by serious multipath interference and frequency offset drifting of narrow-band signals are difficult to solve in complex environments with multipath effect and high frequency offset, such as urban canyons, basements and warehouses. According to the invention, by introducing analog phase locking, digital fine tuning, dual-correlation symbol synchronization based on multi-path sensing and vector amplitude-phase combined compensation overall architecture with cooperation of analog and digital, the problems of synchronization failure and demodulation performance reduction caused by multi-path distortion in the prior art are avoided; and the sensitivity and the overall reliability of radio frequency signal receiving are remarkably improved.

The invention provides a frequency offset processing method and a frequency offset processing device for OFDM (Orthogonal Frequency Division Multiplexing) signals, which can be applied to the technical field of signal processing. The method comprises: processing an initial OFDM signal to obtain a processed OFDM signal, the processed OFDM signal comprising a master synchronization sequence and a plurality of OFDM symbols, each OFDM symbol comprising a plurality of pilot symbols; determining a first frequency adjustment value according to the spectral line position of the high-order spectrum of the primary synchronization sequence; adjusting and processing the frequency of the OFDM signal to obtain an intermediate OFDM signal; for each intermediate OFDM symbol, determining a first phase adjustment value corresponding to each intermediate OFDM symbol according to respective phases of the plurality of intermediate pilot symbols and phases of theoretical pilot symbols corresponding to the plurality of intermediate pilot symbols; and adjusting the phase of the intermediate OFDM signal to obtain a target OFDM signal, the target OFDM signal comprising a plurality of target OFDM symbols.

The invention discloses a Doppler frequency shift compensation method, a Doppler frequency shift compensation device and electronic equipment. The method comprises: a user equipment receiving a first message issued by a satellite, the first message carrying a first compensation value corresponding to a Doppler frequency shift between the satellite and the user equipment, and the first compensation value being used for pre-compensating a downlink signal sent by the satellite; in response to the first message, determining the distance between the user equipment and the beam center position of the satellite; and under the condition that the distance is greater than a preset threshold value, performing post-compensation on the frequency deviation of the received downlink signal according to the first compensation value. According to the invention, the technical problem that the accuracy of satellite compensation and the power consumption of terminal compensation cannot be effectively balanced in a Doppler frequency offset compensation scheme adopted by the related technology by adopting a sending end compensation or receiving end compensation mode is solved.

The invention relates to the technical field of satellite communication, and discloses a low-orbit satellite communication Doppler frequency offset processing method, system and device and a medium, and the method comprises the steps: separating a pilot signal from a received signal; taking the Doppler frequency as a first system state, taking the received signal as first observation data, and performing Doppler frequency offset estimation on the pilot signal by adopting a frequency offset estimation algorithm to obtain a frequency offset estimation value; taking the Doppler frequency as a second system state, taking the frequency offset estimation value as second observation data, and adopting a frequency offset tracking algorithm to perform Doppler frequency offset tracking on the pilot signal to obtain a frequency offset tracking value; and performing frequency offset compensation on the received signal according to the frequency offset tracking value to obtain the received signal after frequency offset compensation. According to the method, the Doppler frequency offset is subjected to streaming processing through Bayesian filtering in the estimation and tracking stages, the complexity of data storage and calculation is effectively reduced, the data updating rate is increased, and therefore the accuracy of low-orbit satellite data is effectively improved.

The invention discloses a Bluetooth chip without a crystal oscillator and a frequency offset estimation method and device thereof. The method comprises the following steps: entering a query scanning state before establishing communication connection with host equipment; searching an ID packet broadcasted and sent by the host equipment in the query state in the query scanning state; when an ID packet is received, the information transmission duration of the ID packet is multiplexed, and the first sampling period number of the information transmission duration is counted; determining the actual output frequency of the PLL unit according to the first sampling period number; and obtaining a frequency offset value of the Bluetooth chip without the crystal oscillator by using the difference between the actual output frequency and the ideal output frequency of the PLL unit. Therefore, the frequency offset estimation of the Bluetooth chip without the crystal oscillator is realized.

A communication frame for an OTFS transmission system includes at least one first-type and at least one second-type block. At least the first-type block includes data signals two-dimensionally arranged along the delay domain and the Doppler domain of which at least one has a superimposed pilot signal. The second-type block includes data signals two-dimensionally arranged along the delay domain and the Doppler domain which may or may not have superimposed pilot signals. At least one second-type block is preceded and followed, in the delay-domain, by first-type blocks, the first-type blocks preceding and following a second-type block having at least one identical data symbol and associated superimposed identical pilot symbol at an identical location in the two-dimensional arrangement. An OTFS transmitter generates and transmits the communication frame, and a receiver uses its properties for compensating oscillator frequency offset and channel estimation.

The invention relates to a method for processing a received signal derived from two continuous phase-modulated signals, comprising the following steps: frequency shifting (102) of the squared received signal so as to produce: a first and a second shifted signal having a spectrum shifted by D / 2 and -D / 2 respectively with respect to a spectrum of the squared signal, where D is a bit rate of each of the two continuous phase-modulated signals; determination (108): of a first and a second frequency at which a power spectral density of the first and second shifted signals takes a first and second maximum value respectively, of a third frequency at which a power spectral density of the squared signal takes a third maximum value; central tendency measurement of the frequencies to estimate (110) a frequency difference between the received signal and each of the two continuous phase-modulated signals. Figure for the abstract: Fig. 3

A method includes: determining a plurality of first subcarrier data items on a plurality of first subcarriers of a first frequency subband; performing first phase rotation on each first subcarrier data item based on a mixing frequency and a first reference frequency corresponding to the first frequency subband; determining a to-be-transmitted signal based on a plurality of first subcarrier data items obtained through first phase rotation; and sending the to-be-transmitted signal. In this way, phase rotation can be performed based on at least the first reference frequency, so that modulation can be correctly implemented without a need to know a mixing frequency of a receiving end. In addition, there is no need to notify the receiving end of the used mixing frequency, and the receiving end can correctly demodulate a received signal even if the receiving end does not know the mixing frequency.

Methods, systems, and devices for wireless communication are described. A first wireless device may receive, from a second wireless device, a first frequency modulated continuous waveform (FMCW) signal via an orthogonal frequency division multiplexing (OFDM) channel. The first wireless device may generate a second FMCW signal based on a set of FMCW parameters associated with the first FMCW signal. The first wireless device may combine the first and second FMCW signals and filter the combined FMCW signal. The first wireless device may sample the combined and filtered FMCW signal in a time domain. The first wireless device may estimate the frequency domain OFDM channel based on sampling the combined and filtered FMCW signal. The first and second wireless devices may communicate OFDM signals via the OFDM channel based on the estimation of the frequency domain OFDM channel.

The invention discloses a vehicle-mounted communication perception integrated system based on a millimeter wave radar AWR1642, and the system achieves the generation, emission and receiving of a linear frequency modulation continuous wave LFMCW signal of a 77GHz frequency band through an AWR1642 monolithic integrated chip, and synchronously completes the environment perception and data communication functions on the same hardware platform. Based on an AWR1642 single-chip scheme, a communication sensing integration function is realized, and system cost and power consumption are greatly reduced through waveform sharing and modulation strategy optimization. Actual measurement results show that the system can effectively process received communication signals while achieving long-distance and high-precision effective sensing, and a solution with high cost performance is provided for an intelligent connected automobile.

The invention discloses a Bluetooth chip without a crystal oscillator and a frequency offset estimation method and device thereof, and the method comprises the steps: searching an ID packet transmitted by host equipment in a query state in a mode of polling a frequency offset value in a paging scanning state; when an ID packet is received in the paging scanning state, a current first frequency offset value is output, and the current first frequency offset value is the frequency offset value of the currently received ID packet in the polling search mode; estimating according to a synchronization head in the ID packet to obtain a second frequency offset value, wherein the second frequency offset value is a frequency offset value of the crystal oscillator-free Bluetooth chip determined based on the synchronization head relative to the host device; and correcting the first frequency offset value by using the second frequency offset value to obtain a final frequency offset value, and performing frequency offset compensation on the crystal oscillator-free Bluetooth chip according to the final frequency offset value to align the clock frequency of the host equipment. In conclusion, in the Bluetooth chip without the crystal oscillator, it can be ensured that the clock of the Bluetooth chip is aligned with the clock of the external host equipment so as to normally transmit and receive data packets.

The invention relates to a frequency domain data processing method and device and network equipment, and belongs to the technical field of communication. The method comprises the following steps: acquiring first frequency domain data, wherein the first frequency domain data is frequency domain data after initial frequency domain data is subjected to channel equalization; according to the frequency domain values of the sampling points of the adjacent non-pilot symbols in the first frequency domain data, determining a phase deviation value between the non-pilot symbols corresponding to the first frequency domain data; frequency offset compensation is carried out on a first channel estimation value of the first frequency domain data based on the phase offset value between the non-pilot symbols, a second channel estimation value of the first frequency domain data is obtained, and the first channel estimation value is the channel estimation value of all occupied resource units on the pilot symbols; determining second frequency domain data based on the first frequency domain data and a second channel estimation value of the first frequency domain data; and performing frequency offset compensation on the symbols in the second frequency domain data based on the phase offset value between the non-pilot symbols to obtain the second frequency domain data after frequency offset compensation. According to the invention, the error of frequency offset estimation in a large railway scene can be reduced.

The invention relates to a frequency conversion clock calibration system for a repeater, and the system comprises a reference frequency deviation obtaining module which obtains the reference frequency deviation range of remote equipment and sets the initial parameters of a frequency deviation calibration experiment during the initialization calibration of a repeater system; the frequency offset calibration experiment module is used for determining a reference frequency offset value of the remote equipment through an experiment; the frequency offset period calculation module is used for calculating the frequency offset period according to the offset value, determining the total number of sampling points according to a preset sampling interval and then calculating a sampling time interval; the historical frequency offset data acquisition module is used for acquiring historical frequency offset data and calculating a frequency offset value by combining the historical frequency offset data with the current sampling time interval; the clock drift detection module is used for detecting clock drift caused by environment temperature, synthesizing a frequency deviation value and a drift degree, and selecting direct calibration or delay compensation; according to the system and the method, the problems of frequency deviation, clock drift, delay compensation and the like are solved through modular design and real-time calibration capability, and the clock precision can be efficiently and accurately ensured in a variable environment.

The invention provides a frequency offset compensation method and device and a medium, and is applied to the technical field of communication. The method comprises the following steps: receiving first information, wherein the first information comprises segmentation compensation configuration used for indicating the terminal equipment to carry out frequency offset compensation; determining bandwidth segments for frequency offset compensation and a compensation value of each bandwidth segment according to the segment compensation configuration; and performing frequency offset compensation on each subcarrier in each section of bandwidth according to the compensation value of each section of bandwidth. By means of the method, the compensation precision of Doppler frequency offset is effectively improved, especially the compensation precision in a large-bandwidth scene, and meanwhile the calculation amount is reduced.

The invention relates to the field of laser communication, and provides a parallel low-complexity frequency offset compensation method, device, equipment and medium, and the method comprises the steps: calculating the M-power variance of N M-PSK signals which are input in parallel, and carrying out the first frequency offset compensation of an original signal through the difference result of N points at intervals; the M-PSK signal is a PSK signal of which the modulation order is M; and solving an N-point M-power spectrum for the signal after the first frequency offset compensation, and performing second frequency offset compensation for the signal after the first frequency offset compensation by using the spectral line position of the M-power spectrum. The two-stage frequency offset compensation method provided by the invention has the characteristics of high dynamic range, low resource consumption, no need of data assistance and support of burst signal processing, and is particularly suitable for a frequency offset compensation scene in a high-speed laser communication link.

This invention relates to the field of satellite communication technology and discloses a method, system, device, and medium for processing Doppler frequency offset in low-Earth orbit (LEO) satellite communication. The method includes: separating a pilot signal from a received signal; using the Doppler frequency as a first system state and the received signal as first observation data, performing Doppler frequency offset estimation on the pilot signal using a frequency offset estimation algorithm to obtain an estimated frequency offset value; using the Doppler frequency as a second system state and the estimated frequency offset value as second observation data, performing Doppler frequency offset tracking on the pilot signal using a frequency offset tracking algorithm to obtain a tracked frequency offset value; and performing frequency offset compensation on the received signal based on the tracked frequency offset value to obtain a frequency offset-compensated received signal. This invention uses Bayesian filtering for streaming processing of the Doppler frequency offset during the estimation and tracking stages, effectively reducing the complexity of data storage and computation, increasing the data update rate, and thus effectively improving the accuracy of LEO satellite data.

The invention discloses a simple and convenient method for improving time-frequency estimation precision, which comprises the following steps of: carrying out segmented cross-correlation operation on a local copy of a main synchronization sequence and a received signal; carrying out secondary filtering on a segmented cross-correlation operation result by utilizing a window function; the window function can be a predefined static window, such as a Gaussian window, a triangular window, a rectangular window and the like, and can also be calculated by using a delay power spectrum of a channel; the maximum value is found in the result of the secondary filtering, and the position of the maximum value is the timing position; and obtaining phase differences of correlation results of different segments at a timing position, and calculating a mean value of the phase differences to obtain frequency offset estimation. According to the method, timing estimation performance and frequency offset estimation performance can be improved, and the synchronization signal detection probability is also improved.

The application provides a blind demodulation analysis method of a signal, a chip, a remote control device and a storage medium. The method comprises the following steps: determining the center frequency of a target signal through a bandwidth scanning strategy; performing mixing processing and analog-to-digital conversion on the target signal to obtain an I-path intermediate frequency digital signal and a Q-path intermediate frequency digital signal, so as to determine the amplitude of the target signal; determining the modulation mode of the target signal according to the change of the amplitude of the target signal within a preset time length; if it is determined that the modulation mode is OOK, determining the amplitude mean value of the target signal, and demodulating the target signal according to the size relationship between the amplitude of the target signal and the amplitude mean value to obtain a baseband signal; if it is determined that the modulation mode is 2FSK, determining the frequency offset estimation mean value and the frequency offset of the target signal, and demodulating the target signal according to the size relationship among the frequency of the target signal, the center frequency of the target signal and the frequency offset estimation mean value to obtain the baseband signal; and performing frequency measurement on the baseband signal to determine the symbol rate.

The invention provides a cell initial access-oriented multi-dimensional parameter estimation method and system, a medium and a receiver. The method comprises the following steps of: receiving a received signal from at least one network node; generating a local reference signal corresponding to each network node signal; for each network node signal, acquiring a rough candidate parameter area based on the received signal and a corresponding local reference signal in a preset multi-dimensional parameter space; and in the rough candidate parameter region, searching the first-dimensional parameter based on a divide-and-conquer method to obtain a matched multi-dimensional parameter estimation value. According to the cell initial access-oriented multi-dimensional parameter estimation method, the cell initial access-oriented multi-dimensional parameter estimation system, the medium and the receiver, high-precision estimation of multi-dimensional parameters can be quickly and efficiently completed.

The application discloses a multi-target parameter estimation method and system based on an OTFS sensing shared waveform, relates to the technical field of communication and sensing integration, and first jointly adopts two representation methods of a discrete DD domain sensing channel and a continuous DD domain sensing channel and corresponding DD domain echo signal modes, and describes a problem model suitable for multi-target sensing and fractional delay Doppler estimation; when a target is sensed, a BCS-ML algorithm in the application estimates target parameters in two stages, estimates integer delay Doppler in the first stage, and estimates fractional delay Doppler in the second stage, the model adopted by the application and the algorithm proposed by the application realize low-complexity parameter estimation and high-precision parameter estimation of multi-target, and break through the limitations of a traditional OTFS sensing parameter estimation algorithm.

An apparatus and method for position estimation are disclosed. The apparatus receives configuration information for a first Reference Signal (RS), and a second RS. The configuration information includes information indicative of a first and second time-frequency resource allocated to the first and second RS respectively. The allocation the resources is based on an estimate of a coherence time and a coherence bandwidth of a channel between the apparatus and a node. The apparatus receives the first and second RSs based on the configuration information and thereafter determines a phase offset between the received first and RSs. The first or second received RS are adjusted based on the phase offset and a third RS is generated for use in position estimation.

This invention discloses a method and system for counter-reconnaissance of wireless communication channels based on known structure and desired transformation-enhanced perturbations, belonging to the field of wireless communication technology. Addressing the problems of traditional jamming methods being easily exposed and inefficient, and the insufficient robustness of existing counter-perturbation channels, this invention employs a desired transformation enhancement framework to generate low-power counter-perturbations with channel pre-adaptability. Dual-channel coordinated transmission ensures accurate signal superposition, and an air interface closed-loop adaptive mechanism provides real-time feedback of channel parameters and dynamically adjusts the perturbation. Simultaneously, the receiving end recovers the original signal based on the known perturbation structure through equalization and scrambling operations. This effectively misleads the enemy's intelligent identification system at low power while ensuring the reliability of friendly communication.

The invention discloses a satellite optical communication blind frequency offset estimation method, device and equipment based on extended phase difference, and a storage medium, and relates to the technical field of signal processing, and the method comprises the steps: obtaining an analog digital signal after digital-to-analog conversion during photoelectric detection; performing phase difference calculation and expansion processing according to the analog digital signal to obtain a phase difference sequence; performing anomaly detection and interpolation reconstruction according to the phase difference sequence to obtain a reconstructed phase difference sequence; and calculating an instantaneous frequency offset according to the reconstructed phase difference sequence, and carrying out noise smoothing processing on the instantaneous frequency offset to obtain a smoothed frequency offset estimation value. According to the invention, abnormal point detection and elimination are carried out on the phase difference sequence of the received signal, and the interpolation algorithm is utilized to reconstruct the continuous phase change track, so that the synchronization precision and link stability of the satellite optical communication system in a large-frequency-offset and high-dynamic scene are improved.

This application discloses a backscattering method and apparatus, terminal equipment, network equipment, and chip, relating to the field of communication technology. The method includes: a transmitting end sending a first signal to a receiving end; the receiving end modulating the received first signal to obtain a second signal, the second signal including at least one of data information, control information, access information, and interactive signals, and the second signal and a third signal being orthogonal, the third signal including at least one of uplink signals, downlink signals, and sidelink signals; and the receiving end sending the second signal back to the transmitting end. It is evident that in passive IoT, the receiving end modulates its own information onto the received first signal to obtain the second signal, and then transmits it to achieve backscattering, thereby saving its own energy consumption through backscattering. Simultaneously, the orthogonality of the second and third signals enables passive IoT to reuse existing cellular network deployments, saving the overhead of separately deploying passive IoT and reducing the complexity of the receiving end.

A communication frame for an Orthogonal Time-Frequency Space (OTFS) transmission system includes at least one first type block and at least one second type block. The first type block comprises data signals arranged in a two-dimensional pattern along the delay and Doppler domains, wherein at least one data signal has a superimposed pilot signal. The second type block comprises data signals arranged in a two-dimensional pattern along the delay and Doppler domains, which may or may not have a superimposed pilot signal. At least one second type block is surrounded by a first type block in the delay domain, and one or more first type blocks surrounding the second type block have at least one identical data symbol and an associated identical superimposed pilot symbol at the same position in the two-dimensional pattern. An OTFS transmitter generates and transmits the communication frame, and a receiver utilizes its characteristics for oscillator frequency offset compensation and channel estimation.

This document discloses a solution for reducing a frequency offset. According to an aspect, a method comprises: acquiring a signal distorted by the frequency offset; estimating a frequency offset estimate describing the frequency offset; computing coefficients for a frequency-domain filter on the basis of a relation between the frequency offset estimate and a combination of the frequency offset estimate and an index of the frequency-domain filter; and performing frequency-domain filtering of the signal by using the computed coefficients.

An inventory method includes taking, by a first communication device, inventory of at least two second communication devices based on a multi-thread inventory process.

The application provides a serial communication interface frequency offset calibration system and method, relates to the technical field of serial communication, and the calibration system comprises: an analog front-end module used for receiving a data signal sent by a host computer and extracting corresponding data edge information, wherein the data edge information represents a time point of a rising edge or a falling edge of the data signal; a signal comparison module used for comparing and processing an internal clock signal of a device with the data edge information to generate frequency offset information; a frequency offset coefficient generation module used for calculating and processing the frequency offset information based on a preset modulation coefficient to generate a frequency offset modulation coefficient; and a phase-locked loop module used for adjusting the frequency of the internal clock signal according to the frequency offset modulation coefficient. The application can realize that the internal clock signal of the device follows the frequency offset of the clock signal of the host computer in real time, saves hardware cost, and improves device compatibility.

Methods, systems, and devices for wireless communications are described. Generally, the described techniques may enable a user equipment (UE) to use a frequency estimator (e.g., a maximum likelihood estimator) that may be based on a pilot signal sent over M distinct symbols. That is, the frequency estimator may be based on all available cross-correlations of pilot signals in a reference signal. In some examples, the frequency estimator may achieve an increased pull-in range and estimation performance based on weighting the available cross-correlations in accordance with the channel statistics. The described techniques may also support asymmetrical symbol spacings between pilot signals in one or more reference signals, which may further improve pull-in range of the frequency estimator. Additionally, or alternatively, aspects of the frequency estimator may be combined with aspects of another frequency estimator to increase the pull-in range with relatively low computation complexity at the UE.