31results about "Carrier regulation" patented technology

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 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.

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.

Aspects of this disclosure relate to frequency offset compensation in a radio receiver. In embodiments of the disclosure, a frequency domain orthogonal frequency-division multiplexing signal can be received, and a phase error offset in individual frequency segments of the frequency domain orthogonal frequency-division multiplexing signal can be compensated for based on estimates of the phase error offset for the individual frequency segments. Related radio receivers and radio systems are disclosed.

According to an example implementation, a method for frequency offset reporting includes transmitting, by a first transceiver, a first tracking reference signal to a user device in a wireless communication system, transmitting, by a second transceiver, a second tracking reference signal to the user device, receiving, by the base station, a channel state information (CSI) reporting signal via an uplink channel, where the CSI reporting signal includes power estimation information. The method includes determining whether to pre-compensate a frequency of a downlink signal with frequency offset information based on the power estimation information, and transmitting, by at least one of the first transceiver or the second transceiver, the downlink signal with the pre-compensated frequency in response to the determination to pre-compensate the frequency of the downlink signal.

The application provides a frequency offset processing method and device of an OFDM signal, 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 main synchronization sequence and a plurality of OFDM symbols, and each OFDM symbol comprising a plurality of pilot symbols; determining a first frequency adjustment value according to a spectral line position of a high-order spectrum of the main synchronization sequence; adjusting the frequency of the processed 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 the phases of a plurality of intermediate pilot symbols and the 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.

Methods and wireless communication devices for mode classification include configuring the wireless communication device to receive a wireless frame transmitted over an operating channel bandwidth, determine a frequency domain signal representing a plurality of symbols carried in the wireless frame, estimate a primary channel bandwidth for the wireless frame from the frequency domain signal, determine a bandwidth field in a signal field of the wireless frame, compare the primary channel bandwidth with the operating channel bandwidth, and a mode used to transmit the wireless frame based on the bandwidth field and the comparing result.

In one embodiment, an apparatus includes: a compensation circuit to select one of a plurality of compensation sets based on an allocated resource unit (RU) and compensate a digital complex signal using the selected compensation set; a digital-to-analog converter to convert the compensated digital complex signal to a compensated analog complex signal; a mixer coupled to the digital-to-analog converter to upconvert the compensated analog complex signal to a radio frequency (RF) signal; and a power amplifier coupled to the mixer to amplify the RF signal.

A system for radio frequency (RF) residual sideband (RSB) calibration includes a complex (in phase / quadrature (I / Q)) signal receiver, a signal generator configured to generate a transmit (Tx) signal, a first phase shifter operably coupled to the real signal transmitter, a first signal combiner configured to combine a receive (Rx) signal with the transmit (Tx) signal to generate a first combined signal, a second phase shifter configured to provide a selected phase shift to the first combined signal, and a complex downconverter configured to generate an in phase Rx signal and a quadrature Rx signal alternatively using an in phase LO signal and a quadrature LO signal to generate one or more signals indicative of relative Tx-Rx LO phase (θ), amplitude (A), Tx LO I / Q phase mismatch (ε), Rx I / Q amplitude mismatch (α), and Rx I / Q phase mismatch (φ) at the output of the complex receiver.

The disclosure provides a timing control method, a timing control apparatus, an electronic device, a chip, and a storage medium. The method includes: tracking, with a first subcarrier spacing, a reference signal sent by a network device, to obtain a timing offset; adjusting a time unit corresponding to a second subcarrier spacing according to the timing offset; and performing carry system counting on a time unit corresponding to the first subcarrier spacing when a length of the time unit corresponding to the second subcarrier spacing is reached. Therefore, time units corresponding to different subcarrier spacings may be adjusted and counted associatively and it may also be used to solve the problem of slot misalignment caused by ATC adjustments of different subcarrier spacings as well as the problem of complex or impossible conversion of slot numbers corresponding to different subcarrier spacings when performing handovers on the subcarrier spacings.

The present application provides a communication method and a communication system. The communication method, applied to a transmitter, includes: collecting a bitstream; modulating and converting the bitstream and obtaining a frequency domain signal matrix; multiplying the frequency domain signal matrix with an inverse approximate Discrete Fourier Transform (DFT) matrix and obtaining a time domain signal matrix; post-processing the time domain signal matrix and obtaining a time domain signal, and sending the time domain signal to a receiver connected with the transmitter. The communication method, applied to a receiver, includes: receiving a time domain signal from a transmitter connected with the receiver; pre-processing the time domain signal and obtaining a time domain signal matrix; multiplying the time domain signal matrix with an approximate DFT matrix and obtaining a frequency domain signal matrix; demodulating and converting the frequency domain signal matrix and obtaining a bitstream.

Example frequency compensation methods and apparatus are described. One example method includes determining first information and sending the first information by a network device to a terminal device, where the first information indicates a frequency compensation manner of an uplink signal of the terminal device or the first information indicates a configuration parameter of the terminal device. The terminal device receives the first information, and determines, based on the first information, the frequency compensation manner to be used to send the uplink signal. The terminal device performs frequency compensation for the uplink signal based on the frequency compensation manner.

An apparatus has one or more memories and one or more processors coupled to the one or more memories. The processor(s) is configured to obtain a first frequency modulated continuous wave (FMCW) waveform having a first center frequency. The first FMCW waveform has a first FMCW signal, and a second FMCW signal that intersects with the first FMCW signal. The processor(s) is also configured to obtain partial information of a cell identifier (ID). The obtaining is associated with a frequency offset between the first center frequency and a synchronization raster frequency. The processor(s) is further configured to perform cell detection based on the partial information of the cell ID.

The application provides a kind of optical fiber communication system carrier phase recovery method and device.Method includes using linear time domain data filtering to carry out predicted receiving signal carrier phase noise in the receiving end of optical fiber communication system;According to the predicted carrier phase noise, the receiving signal is pre-rotated, and the carrier phase noise is pre-compensated;Residual error of the receiving signal after pre-rotation is estimated by power iteration method, for extracting the error between predicted carrier phase noise and actual phase noise;According to the error between the predicted phase noise and the actual phase noise extracted, the next state quantity of linear time domain data filtering is updated, and the carrier phase recovery is realized.The method can effectively solve the carrier phase recovery problem in optical fiber communication system, and has good algorithm robustness under low signal-to-noise ratio condition, and low computational complexity.

A communication apparatus having a frequency tracking mechanism is provided. A phase compensation circuit performs phase compensation on a packet according to a frequency offset to generate a phase-compensated symbol section for a symbol processing circuit to descramble and equalize thereon to generate a phase difference and a difference from a previous symbol section such that a residual frequency offset estimation circuit calculates a ratio to generate an instant frequency offset estimation value. A frequency offset smoothing calculation circuit performs calculation according to a function having a positive correlation with the difference to generate a modification coefficient to be multiplied by the instant frequency offset estimation value and a smoothing coefficient to generate a smoothed frequency offset estimation value and adds a previous frequency offset estimation value by the smoothed frequency offset estimation value to generate a current frequency offset estimation value to update the frequency offset.

This application discloses a digital demodulation method, apparatus, device, and storage medium, relating to the field of digital communication. The method includes: acquiring a filtered signal of a transmitted signal after passing through a filter, and performing phase differential on the filtered signal; extracting the obtained differential phase and determining the signal to be demodulated based on the differential phase; determining the target differential phase of the filtered signal according to the current communication environment, and constructing a composite grid based on the target differential phase; determining sub-grids based on the composite grid, and determining the branch path metric and total path metric of the signal to be demodulated based on the sub-grids; performing Viterbi demodulation based on the total path metric, and obtaining the demodulation result by backtracking the Viterbi demodulation based on the total path metric. This application constructs a composite grid phase compensation model for GMSK and proposes a composite Viterbi demodulation algorithm for GMSK signals based on differential phase, which can overcome the influence of Doppler frequency offset on demodulation performance and maintain excellent performance even with large frequency offsets.

A method for phase correction includes determining a channel impulse response of a first component carrier associated with a first bandwidth, and determining a location of a first impulse response peak within the first bandwidth. A location of a second impulse response peak within a second bandwidth associated with the first component carrier or with a second component carrier is determined based on the location of the first impulse response peak. The second bandwidth is disjoint with the first bandwidth. A phase correction of one of a channel frequency response of the first bandwidth and a channel frequency response of the second bandwidth is performed based on the first impulse response peak and the second impulse response peak.

The present disclosure relates to a time synchronization method, device, equipment, storage medium and vehicle. The method is applied to a controller of a time synchronization device, the time synchronization device further comprising a first crystal oscillator and a second crystal oscillator, and the method comprises: receiving a message transceiving time and a local time collected by the first crystal oscillator; calculating a delay time between the time synchronization device and a master clock device according to the message transceiving time; calculating a master clock time of the master clock device based on the delay time and the message transceiving time; and sending the master clock time and the local time to the second crystal oscillator, the second crystal oscillator being configured to synchronize the local time with the master clock time. The time collected by the first crystal oscillator is accurate time, and thus the master clock time obtained is of high accuracy. Therefore, the above-mentioned time synchronization method applies double crystal oscillators, improves the accuracy of the calculation of the master clock time, further improves the time synchronization accuracy, and meets the demand for precise control of the vehicle.

This application discloses a frequency offset tracking method, apparatus, device, and medium, relating to the field of wireless communication. The method involves receiving a burst direct sequence spread spectrum signal; generating multiple parallel frequency correction values ​​based on the burst direct sequence spread spectrum signal and a local carrier; wherein the local carrier is generated based on the burst direct sequence spread spectrum signal; despreading the multiple parallel frequency correction values ​​to generate corresponding multiple parallel correlation matching values; merging the multiple parallel correlation matching values; and performing frequency offset tracking using a frequency-locked loop method and the merged correlation matching values. Therefore, the above scheme performs parallel multi-path frequency offset correction on the received burst direct sequence spread spectrum signal and then performs frequency offset tracking using a frequency-locked loop method. This not only achieves high-precision frequency offset tracking but also adapts to large frequency offset change rates, enabling frequency tracking of burst direct sequence spread spectrum signals under high dynamic conditions.

Methods, systems, and devices for wireless communications are described. A user equipment (UE) may transmit a capability message indicating a capability of the UE to estimate a frequency domain imbalance between an in-phase portion of a transmission chain of a network entity and a quadrature-phase portion of the transmission chain of the network entity. The UE may receive, based on the capability message, an indication of a coherence bandwidth associated with the frequency domain imbalance. The coherence bandwidth may indicate a quantity of subcarriers (SCs) over which a characteristic of the frequency domain imbalance (e.g., a change in amplitude of the frequency domain imbalance) satisfies a threshold. The UE may perform an estimation of the frequency domain imbalance based on the coherence bandwidth. In some examples, the UE may receive downlink signals from a network entity and may perform a correction of the downlink signals based on the estimation.

A terminal according to an aspect of the present disclosure comprises: a reception unit which receives information relating to a reference carrier; and a control unit which performs a first Doppler correction on the reference carrier on the basis of the information, and performs a second Doppler correction on a carrier other than the reference carrier on the basis of the information and the first Doppler correction. According to an aspect of the present disclosure, Doppler correction can be appropriately performed.

Methods, systems, and devices for wireless communications are described. A user equipment (UE) may transmit a capability message indicating a capability of the UE to estimate a frequency domain imbalance between an in-phase portion of a transmission chain of a network entity and a quadrature-phase portion of the transmission chain of the network entity. The UE may receive, based on the capability message, an indication of a coherence bandwidth associated with the frequency domain imbalance. The coherence bandwidth may indicate a quantity of subcarriers (SCs) over which a characteristic of the frequency domain imbalance (e.g., a change in amplitude of the frequency domain imbalance) satisfies a threshold. The UE may perform an estimation of the frequency domain imbalance based on the coherence bandwidth. In some examples, the UE may receive downlink signals from a network entity and may perform a correction of the downlink signals based on the estimation.

A means for reducing errors in unused tones in a partial bandwidth wireless transmission system is provided. In one embodiment, the means includes: a compensation circuit for selecting one of a plurality of compensation sets based on an allocated resource unit (RU) and using the selected compensation set to compensate a digital complex signal; a digital-to-analog converter for converting the compensated digital complex signal into a compensated analog complex signal; a mixer coupled to the digital-to-analog converter for up-converting the compensated analog complex signal into a radio frequency (RF) signal; and a power amplifier coupled to the mixer for amplifying the RF signal.

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.

The application provides a kind of underwater acoustic signal Doppler estimation method based on improved firefly algorithm, adopts pseudo-random sequence to construct transmitting signal, improves signal in mobile underwater acoustic communication scene anti-multipath interference, broadband Doppler effect ability;At receiving end, first, through larger step size, Doppler is roughly estimated, in the narrowed Doppler factor search range, based on variable scale chaos strategy, improved firefly algorithm is used, the correlation of received signal and local reference signal carrying different Doppler factors is used to construct objective function, the fitness value is calculated, the Doppler estimation is converted into continuous optimization problem, with lower calculation complexity, the Doppler estimation precision meeting the synchronization demand of underwater acoustic communication is obtained, and the estimation stability in larger Doppler range is guaranteed by using the Doppler sensitive property of the method.

A method and a device in a node for wireless communications. A first node receives a first information block and a second information block; and receives a first radio signal in a first time-frequency resource set; the first information block is used to determine a first transmission configuration parameter group, the first transmission configuration parameter group comprising multiple transmission configuration parameters; the multiple transmission configuration parameters are respectively used to determine multiple reference signals, with a first reference signal being one of the multiple reference signals; there is a first-type relationship between the first radio signal and the first reference signal, and there is a second-type relationship between the first radio signal and one of the multiple reference signals other than the first reference signal. The method given in the present application can enhance the performance of offsetting Doppler Shift in multi-TRP scenarios.