A method is disclosed for synchronization, comprising obtaining baseband signal samples of a baseband information signal having an in-phase signal sample and a quadrature signal sample, the baseband information signal having been generated by mixing a received modulated carrier signal with a local oscillator (LO) signal having an LO frequency, the modulated carrier signal being an in-phase signal and quadrature signal having a substantially uncorrelated nature and derived from different input data sets; determining an offset frequency rotation based on an estimated residual correlation between the in-phase signal samples and the quadrature signal samples; and, deriving synchronization information from the offset frequency rotation, wherein the received modulated carrier signal is a quadrature-modulated signal with arbitrary orthogonal in-phase and quadrature signal components.

A receiver device implements enhanced data reception with edge-based clock and data recovery such as with a flash analog-to-digital converter architecture. In an example embodiment, the device implements a first phase adjustment control loop, with for example, a bang-bang phase detector, that detects data transitions for adjusting sampling at an optimal edge time with an edge sampler by adjusting a phase of an edge clock of the sampler. This loop may further adjust sampling in received data intervals for optimal data reception by adjusting the phase of a data clock of a data sampler such a flash ADC. The device may also implement a second phase adjustment control loop with, for example, a baud-rate phase detector, that detects data intervals for further adjusting sampling at an optimal data time with the data sampler.

A data transmitter for transmitting a data packet to a data receiver via a communication channel includes a generator for generating the data packet and a transmitter for transmitting the data packet. The generator for generating the data packet is configured to generate a data packet having a first data block and a second data block and a predefined first reference sequence and second reference sequence for synchronizing the data receiver, wherein the first reference sequence is longer than the second reference sequence, and wherein in the data packet, the second data block is located between the first reference sequence and the second reference sequence, and the first reference sequence is located between the first data block and the second data block. The transmitter for transmitting the data packet is configured to transmit the data packet to the data receiver via the communication channel.

The proposed solution relates to a method and an apparatus in a communication system. The solution includes receiving as an input a frame including of a set of data symbols and reference symbols, each data symbol forming a rectangular symbol constellation of samples, derotating the first symbol of the set on the basis of the reference symbols, and setting phase rotating angle of the first symbol as zero. The solution further includes for each following successive symbol in the set of symbols: performing equalization; reducing the number of samples in the constellation by selecting samples in two or more corners of the constellation by utilizing two or more threshold values; estimating the phase rotating angle of the symbol from the reduced number of samples and derotating the symbol on the basis of the determined phase rotating angle.

A method of modifying a common phase error (CPE) estimate of a slot including symbols, the method including receiving a CPE value corresponding to a symbol of a slot by an artificial neural network, generating a modified CPE value with the artificial neural network, and outputting the modified CPE value from the artificial neural network.

The present invention generally relates to the field of electrical communication and more specifically to apparatuses and methods of phase noise mitigation for signal transmission in wideband telecommunication systems.

The method for compensation of the phase noise effect on the data transmission through a radio channel is based on a possibility to present the phase noise of a reference oscillator like a random process where the main spectral density is concentrated in the low-frequency region. Therefore, the number of estimated parameters can be reduced many times to several low-frequency spectral components instead of a direct estimation in the time domain.

The advantage of the method is an improvement of the estimation accuracy and a reduction of the computational complexity.

A transmitter with compensating mechanism of pulling effect includes an output unit and a correction unit. The output unit mixes a first correction signal and a second correction signal according to an oscillating signal to generate a modulated signal, and to amplify the modulated signal to generate a first output signal. The correction unit analyzes the power of the first output signal to generate a first coefficient and a second coefficient, and generate the first correction signal and the second correction signal according to the first coefficient, the second coefficient, an in-phase data signal, and a quadrature data signal.

An OFDM system synchronization tracking method includes: A1: performing OFDM symbol segmentation on a received digital signal, performing FFT on OFDM symbols obtained through the segmentation, performing step A2 to A5 on each frequency domain OFDM symbol in a frequency domain OFDM symbol sequence; A2: extracting information subcarrier symbols, pilot symbols, a DC subcarrier from a current frequency domain OFDM symbol, detecting and implementing a decision on the information subcarrier symbols, generating a recovery information subcarrier symbol; A3: recovering the OFDM symbol; A4: performing frequency offset estimation and timing offset estimation on the recovery OFDM symbol; A5: performing phase compensation on a next frequency domain OFDM symbol in the frequency domain OFDM symbol sequence by using a frequency offset estimation phase rotation value and a timing offset estimation phase rotation value, setting the compensated frequency domain OFDM symbol to a current frequency domain OFDM symbol, returning to the step A2.

Automatic frequency controllers, automatic frequency control methods, wireless communication devices, and/or wireless communication methods are provided. The automatic frequency controllers for correcting a frequency offset between a base station and a terminal includes at least one processor communicatively coupled to a memory and configured to execute computer-readable instructions stored in the memory to obtain a phase estimate from a reference signal received from the base station; classify a downlink channel as a High Speed Train (HST) channel or a non-HST channel based on the phase estimate; adjust a loop gain according to the classified downlink channel; calculate a phase error based on the phase estimate and the loop gain; correct the frequency offset using the phase error; and communicate with the base station after correcting the frequency offset.

A system and method for transmitting an orthogonal frequency-division multiplexed signal with a group distributed phase tracking reference signal subcarrier structure, and for estimating, and compensating for, both common phase error, and inter-carrier interference.