20 results about "Residual frequency offset" patented technology

The invention relates to a Doppler frequency offset compensation method based on double-link cooperation and a satellite communication system. The Doppler frequency offset compensation method comprises the following steps that a UHF transmitter of a mobile platform terminal sends GPS information data of the mobile platform terminal to a UHF receiver of a satellite end; the UHF receiver of the satellite end receives GPS information data of the mobile platform terminal and transmits the GPS information data to the Ka receiver of the satellite end; a Ka receiver at the satellite end calculates UHF Doppler frequency offset by using the GPS information data of the mobile platform terminal and the position and speed of the satellite, and calculates Ka Doppler frequency offset based on the UHF Doppler frequency offset; injecting the Ka Doppler frequency offset into a local oscillator synthesizer of a Ka receiver at a satellite end to carry out Ka Doppler frequency offset pre-compensation; and compensating the pre-compensated residual frequency offset by using the phase-locked loop. According to the Doppler frequency offset compensation method, the time delay bottleneck of Ka link frequency offset compensation is highlighted, and the requirement that the end-to-end time delay of low-orbit satellite real-time services is smaller than or equal to 50 ms is met.

The application relates to a UWB preamble signal receiving processing method, which comprises the following steps: receiving a discrete digital signal obtained through sampling conversion after front-end processing; in a coarse acquisition stage, a locally reproduced preamble sequence is used to perform convolution processing on the discrete digital signal, coherent accumulation and fast Fourier transform are performed on the signal after convolution processing to obtain a first processing signal, a preamble is detected according to the strongest peak value response of the first processing signal, and frequency offset coarse estimation and CMR coarse estimation are performed when the preamble is detected; in an accurate receiving stage, the signal after convolution processing is subjected to frequency offset coarse compensation processing by using the frequency offset coarse estimation to obtain a compensation signal, interpolation processing is performed by taking the compensation signal as input, coherent accumulation and fast Fourier transform are performed on the signal after interpolation processing to obtain a second processing signal, residual frequency offset estimation and CMR accurate estimation are performed on the second processing signal. The application can improve the reliability of preamble detection and acquisition.

Systems, methods, apparatuses, and computer program products for physical layer specification support for the reduction of reference signal resource overhead for time-and frequency tracking reference signal. For example, some example embodiments may include a method comprising receiving, by a user equipment, at least one indication comprising at least one symbol configuration associated with at least one reference signal; and determining, by the user equipment, based on the received indication, at least one of residual frequency offset or residual phase offset based on the at least one reference signal.

The invention provides a low-orbit satellite Doppler frequency offset compensation method, device and equipment and a medium, and the method comprises the steps: dividing a coverage area into a plurality of continuous frequency offset subareas based on the real-time orbit parameters of a low-orbit satellite and the geographical range information of the coverage area; for each frequency offset partition, according to the partition characteristic parameters of the frequency offset partition, adjusting the beam forming parameters of the low-orbit satellite so as to perform Doppler frequency offset compensation on the frequency offset partition; selecting a part of terminals from each frequency offset partition, and obtaining residual frequency offset information fed back by the part of terminals; and dynamically adjusting the beam forming parameters of the corresponding frequency offset partitions according to the residual frequency offset information fed back by part of the terminals. According to the embodiment of the invention, the influence of terminal movement and track disturbance on compensation precision can be effectively suppressed, deep coupling of beam regulation and frequency offset characteristics is realized, the frequency offset fluctuation in the beam is stabilized in a traceable range of a terminal phase-locked loop, and continuous and reliable communication of the terminal in a high-speed movement process is ensured.

This application relates to the field of intelligent conditioning technology for grating filter sensing signals, and discloses a grating filter sensing signal conditioning method based on machine learning. The invention acquires observation response characterization data and conditional constraint state quantities, first performs spectral axis registration processing based on a preset reference frequency window to eliminate the influence of measurement coordinate offset, then performs residual frequency offset decoupling processing on the preset target frequency band to extract residual frequency offset characterization quantities, and constructs a residual dynamic state sequence by combining historical control states, further utilizes a preset time-series inference model to output voltage compensation quantity and conditioning reliability results, and finally determines the final control voltage through reliable gating conditioning and local spectrum scanning verification, thereby effectively distinguishing pseudo offset from the preset target frequency band true offset, and reducing the interference of original observation signal fluctuations, environmental changes and uneven internal electric field distribution on the control results.

The invention relates to the technical field of satellite communication, in particular to a satellite communication frequency offset estimation and synchronization method, a storage medium and a satellite communication terminal.The satellite communication frequency offset estimation and synchronization method comprises the steps that a satellite wireless signal containing a frequency correction channel burst and a broadcast control channel burst is received; detecting frequency correction channel burst to obtain coarse carrier frequency offset; positioning baseband data corresponding to a broadcast control channel burst in the satellite wireless signal; pre-compensating baseband data corresponding to the broadcast control channel burst by using coarse carrier frequency offset, and calculating residual frequency offset of a residual frequency offset signal; obtaining a total carrier frequency offset according to the coarse carrier frequency offset and the residual frequency offset; and performing complete compensation, demodulation and channel decoding on the baseband data corresponding to the broadcast control channel burst by using the total carrier frequency offset to obtain decoded data. According to the method, the coarse estimation of the FCCH and the fine estimation and verification mechanism of the BCCH are combined, and the synchronization reliability can still be ensured under the complex channel condition.

Systems, methods, apparatuses, and computer program products for physical layer specification support for the reduction of reference signal resource overhead for time-and frequency tracking reference signal. For example, some example embodiments may include a method comprising receiving, by a user equipment, from a network entity, at least one indication comprising at least one antenna port identifier associated with at least one reference signal; and determining, by the user equipment, based on the received indication, at least one of residual frequency offset or residual phase offset based on the at least one reference signal.

The invention discloses a self-adaptive dual-threshold quick capture method and device in satellite communication and a medium. The method comprises the following steps: performing down-conversion mixing and residual frequency offset removal on IQ data and a local sweep frequency control carrier to obtain first data; performing AGC amplification processing on the first data to obtain second data with a predetermined amplitude; performing timing deviation removal on the second data to obtain third data; performing correlation accumulation on the third data to obtain fourth data; according to the fourth data, capturing and tracking are carried out based on a self-adaptive double-threshold mode, the position of a frame header is identified, and captured data are obtained; the self-adaptive double-threshold value is a double-threshold value capturing mode of capturing a high threshold value and tracking a low threshold value. The method has the advantages of high-probability capture and low-probability missed alarm.

This disclosure provides a fine timing method, apparatus, electronic device, storage medium, and chip, including determining the residual frequency offset of a first target frequency and a second target frequency in a detection sequence; wherein the first target frequency and the second target frequency are determined when the detection sequence is converted into a spectrum; determining the adjustment amount of the DC component at the first target frequency and the second target frequency based on the residual frequency offset; determining the phase of the first target frequency and the second target frequency based on the adjustment amount; and determining the fine timing adjustment amount based on the phase of the first target frequency and the second target frequency. Compared with related technologies, this disclosure, by determining the residual frequency offset, determining the adjustment amount of the first target frequency and the second target frequency based on the residual frequency offset, and determining the phase based on the adjustment amount, makes the fine timing adjustment amount obtained based on the phase more accurate, and makes the TOA estimate more accurate.

The method for fine timing provided by the present disclosure comprises the following steps: acquiring residual frequency offset of a detection sequence determined according to a target signal point and a marker signal point in the detection sequence, wherein the target signal is a sampling point in the detection sequence except the marker signal; correcting the residual frequency offset according to the target signal and the marker signal to obtain a corrected detection sequence; determining phase values of a first target frequency point and a second target frequency point in the corrected detection sequence, wherein the first target frequency point and the second target frequency point are determined when the detection sequence is converted into a frequency spectrum; and determining a fine timing adjustment amount according to the phase values of the first target frequency point and the second target frequency point. By determining the residual frequency offset and correcting the residual frequency offset in the detection sequence, the phase values are calculated according to the corrected detection sequence, so that the fine timing adjustment amount based on the phase values is more accurate, and the accuracy of the estimated value of TOA is improved.

The application provides a residual frequency offset and phase offset joint estimation method and device based on linear fitting, which comprises the following steps: obtaining symbol data after symbol synchronization based on a preset target modulation mode, obtaining a signal model based on the symbol data, obtaining a continuous phase sequence of the signal model, performing linear fitting based on the continuous phase sequence, calculating a residual frequency offset estimation value, compensating the signal model based on the residual frequency offset estimation value to obtain a target signal model after residual frequency offset compensation, performing operation on the target signal model and solving to obtain a phase value of each symbol sample, taking an average value of the phase value of each symbol sample to obtain a final initial phase offset estimation value, and performing phase compensation on the target signal model based on the initial phase offset estimation value to obtain target symbol data after final carrier synchronization.

The application discloses a frequency offset calculation method and a terminal in a high-frequency high-speed frequency hopping system. The frequency offset calculation method comprises the following steps: performing first correction on a received signal according to an initial frequency offset at a receiving end; rotating synchronization header data of the received signal, so that the phase of the rotated synchronization header data and the phase of service data are located in the same quadrant; combining the rotated synchronization header data and the service data; performing first equalization calculation on the combined data to obtain an average frequency offset of the combined data; performing second correction on the received data after the first correction based on the average frequency offset of the combined data to obtain corrected data; and performing second equalization calculation on the corrected data to obtain an accurate received signal. Through the calculation of the average frequency offset, the twice correction and equalization calculation are performed on the received data, the residual frequency offset range is reduced, and the accuracy of the received signal is improved.

The invention discloses a communication device and method with a frequency offset tracking mechanism. The method comprises the following steps: a phase compensation circuit receives a current symbol section of a data part of a packet and performs phase compensation according to a frequency offset to generate a phase compensation symbol section; the symbol processing circuit descrambles and balances the phase compensation symbol section according to the scrambling information, and further calculates and generates a phase difference and a data time difference between the symbol section and a previous symbol section according to a balancing result, and then the residual frequency offset estimation circuit performs specific value calculation to generate an instantaneous frequency offset estimation value. The frequency offset smoothing calculation circuit calculates the data time difference according to a function in positive correlation with the data time difference to generate a correction coefficient, multiplies the instantaneous frequency offset estimation value and the smoothing coefficient to generate a smoothing frequency offset estimation value, and then superposes the smoothing frequency offset estimation value with a previous frequency offset estimation value to generate a current frequency offset estimation value to update the frequency offset quantity.

The invention relates to a cascade carrier frequency offset estimation method and device and a storage medium. The method comprises the following steps: generating an initial local carrier signal, and performing coherent demodulation processing on a received quadrature amplitude modulation signal to obtain an initial receiving demodulation signal; performing discrete Fourier transform carrier coarse acquisition with adaptive precision adjustment, regenerating a coarse acquisition local carrier signal, performing coherent demodulation processing and clock synchronization on the quadrature amplitude modulation signal again, and outputting a first demodulation symbol; compensating the first demodulation symbol through a direct judgment phase-locked loop to obtain a second demodulation symbol, finding and outputting an ideal constellation symbol through a direct judgment method, and determining a second phase offset; tracking the phase error through phase integration and loop filtering according to the second phase offset, and determining a phase error tracking result; and determining the residual frequency offset of the first demodulation symbol according to the phase error tracking result. The method is high in anti-noise capability and high in execution efficiency.

The invention discloses a frequency offset synchronization control method and system, network equipment and a storage medium. The method comprises the following steps: receiving an uplink signal from a terminal; performing residual frequency offset detection on the uplink signal to obtain a detection result; residual frequency offset compensation control information is generated based on the detection result, and the residual frequency offset compensation control information is used for feeding back real uplink residual frequency offset to the terminal; and sending the detection result to the terminal through the residual frequency offset compensation control information so as to guide the terminal to pre-compensate a subsequently transmitted uplink signal according to the detection result provided in the residual frequency offset compensation control information. According to the invention, the technical problem of low residual frequency offset compensation accuracy caused by factors such as ephemeris information accuracy, equipment processing time delay and hardware crystal oscillator oscillation precision in the prior art is solved.

The invention relates to the technical field of communication, and discloses a joint frequency offset estimation method, device and equipment based on pilot frequency and data, and the method comprises the steps: determining a frequency offset search range based on a preset frequency offset estimation resolution, and enabling the frequency offset search range to cover a residual frequency offset range; based on each candidate frequency offset in the frequency offset search range, performing frequency offset compensation on the received signal to obtain a compensation pilot symbol and a compensation data symbol; performing channel estimation on the compensation pilot symbol to obtain an estimated channel; balancing the compensation data symbol based on the estimation channel to obtain a balanced symbol; and calculating a symbol error of the equalization symbol, and determining a target frequency offset based on the symbol error corresponding to each candidate frequency offset. According to the method, the pilot symbols and the data symbols are combined for frequency offset estimation, dependence on long data is eliminated, the frequency offset estimation error of the terminal on the residual frequency offset can be met, and the communication quality under narrowband satellite communication is effectively guaranteed.

The invention provides a method and a system suitable for an integrated tester to analyze Wi-Fi OFDMA multi-user performance, and the method comprises a Client field splitting step, a Client channel estimation step, a Client residual frequency offset estimation step, a Client equalization step, a Client pilot frequency tracking step, a Client demodulation step, a first judgment step, a Client result analysis step, a second judgment step and an integrated signal analysis step. By tracking and demodulating the pilot frequency of each OFDM symbol in each Client and splitting and analyzing the signal corresponding to each Client, after an integrated tester uses the method, the measurement requirement that the DUT sends the signal to a plurality of Clients through OFDMA (Orthogonal Frequency Division Multiple Access) can be met, various receiving indexes of each accessed Client and the overall receiving index of the DUT can be evaluated, and the overall performance of the DUT can be improved. And the signal analysis requirement of the integrated tester on the multi-user OFDMA access of the DUT equipment is met.

A method for compensating for and calibrating a frequency offset is performed by a terminal, and includes: compensating or precompensating a target frequency according to a downlink frequency offset; obtaining an uplink residual frequency offset sent by a network device, the uplink residual frequency offset corresponding to an uplink signal sent by the terminal; and calibrating a compensation frequency or a precompensation frequency for the target frequency according to the uplink residual frequency offset.

The invention provides a frequency offset residual error and phase noise joint compensation method for a lightning stroke scene, and relates to the technical field of signal processing, and the method comprises the steps: obtaining two-dimensional time domain data corresponding to an output balance baseband I / Q of a coherent optical receiver, and sequentially carrying out the phase observation construction and frequency preprocessing of the two-dimensional time domain data, so as to obtain an observation vector sequence; based on the observation vector sequence, the weight information of each observation sample and a preset subcarrier set, constructing a weighted sample covariance matrix, performing characteristic decomposition on the weighted sample covariance matrix, obtaining information subspace, noise subspace and phase jump characteristics caused by lightning stroke, constructing a joint cost function, and calculating the phase jump characteristics of the information subspace, the noise subspace and the lightning stroke. Obtaining residual frequency offset and random phase noise at each sampling frequency point according to the optimal solution of the joint cost function; and performing frequency and phase joint compensation on the received coherent optical baseband signal according to the residual frequency offset and the random phase noise. According to the invention, suppression of inter-carrier interference caused by frequency offset and phase noise is facilitated.

This application relates to the field of satellite communication technology, specifically to a satellite communication frequency offset estimation and synchronization method, a storage medium, and a satellite communication terminal. The satellite communication frequency offset estimation and synchronization method includes: receiving a satellite radio signal containing a frequency correction channel burst and a broadcast control channel burst; detecting the frequency correction channel burst to obtain a coarse carrier frequency offset; locating the baseband data corresponding to the broadcast control channel burst in the satellite radio signal; pre-compensating the baseband data corresponding to the broadcast control channel burst using the coarse carrier frequency offset, and calculating the residual frequency offset for the residual frequency offset signal; obtaining the total carrier frequency offset based on the coarse carrier frequency offset and the residual frequency offset; and performing full compensation, demodulation, and channel decoding on the baseband data corresponding to the broadcast control channel burst using the total carrier frequency offset to obtain decoded data. This invention combines coarse estimation of the FCCH with fine estimation and verification mechanisms of the BCCH, ensuring the reliability of synchronization even under complex channel conditions.