In an embodiment a device includes a first circuit and a second circuit, wherein the first circuit is configured to generate a fourth signal and a fifth signal by applying the phase shift respectively to a first signal and to a second signal and deliver a sixth signal corresponding to a sampling over one bit of the fourth signal, a seventh signal corresponding to a sampling over one bit of the fifth signal, an eighth signal corresponding to a sampling over one bit of a difference between the fourth and fifth signals, and a ninth signal corresponding to a sampling over one bit of a sum between the fourth and fifth signals, wherein the second circuit is configured to receive the sixth, seventh, eighth, and ninth signals and determine, during a first phase where the first and second signals are representative of a first known symbol of a QPSK constellation, a state of a first bit from among a first state and a second state based on the eighth and ninth signals.

Provided is a synchronization method, which includes: a first device periodically sends a first PSS sequence and first PDSCH control information at frequency points F.sub.1 to F.sub.N in sequence, where the first PSS sequence and the first PDSCH control information are used for a second device to detect the first PSS sequence and detect the first PDSCH control information; the first device receives signals at frequency points f.sub.1 to f.sub.M in sequence and detects a second PSS sequence; when the second PSS sequence is detected, the first device obtains second half-frame synchronization information and detects second PDSCH control information according to the second half-frame synchronization information; and when the second PDSCH control information is detected, the first device obtains second frame synchronization information and enters a synchronization state. Also provided are a synchronization device, a synchronization system, and a computer-readable storage medium.

The present disclosure relates to methods for indicating a direct current subcarrier and communication apparatuses. In one example method, a second communication apparatus may explicitly or implicitly indicate a location of a first direct current subcarrier and a location of a second direct current subcarrier to a first communication apparatus. The first direct current subcarrier is a direct current subcarrier corresponding to a transmit frequency used by the second communication apparatus. The second direct current subcarrier is a direct current subcarrier corresponding to a receive frequency used by the first communication apparatus.

Joint estimation of the framer index and the frequency offset in an optical communication system are described among various other features. A transmitter can transmit data frames using pilot and framer symbols. A receiver can estimate the framer index and frequency offset using the pilot and framer symbols, and identify the beginning of a header portion of a data frame. By identifying the beginning of the header portion of a data frame, the receiver can synchronize, with less error, the data transmitted by the transmitter and the data it received. To further improve the framer index estimation, a lock indicator signal can be generated to signal to other receiver components that the estimated framer indices are reliable. The receiver can determine frequency offset and additional framer index estimations with increased reliability when performed after the lock indicator signal is generated.

Provided are a configuration method and a transmission method of a new reference signal for frequency offset estimation in a novel wireless communication system. The method may include configuring a synchronization signal to be transmitted through a first bandwidth part of one or more bandwidth parts configured by dividing an entire bandwidth into one or more parts, allocating the one or more reference signals for estimating the frequency offset on one or more resources other than a resource for configuring the synchronization signal, and transmitting the one or more reference signals for estimating the frequency offset.

Embodiments of the present application provide a signal transmission method, a terminal, a network device, and a storage medium. The method comprises: receiving multiple first downlink signals; determining downlink receiving frequency corresponding to the first downlink signal, and respectively determining, on the basis of the downlink receiving frequency corresponding to the first downlink signal, transmitting frequency of uplink signals in association with the first downlink signal; and transmitting the uplink signals on the basis of the transmitting frequency of the uplink signals, wherein a frequency shift determined on the basis of the uplink signals in association with the first downlink signal is used for determining transmitting frequency of second downlink signals. In the embodiments of the present application, a pre-compensation of a downlink Doppler shift is performed by means of each transmission receiving point, and therefore, an error of channel estimation is reduced, and the performance of downlink transmission is improved.

Systems, methods, apparatuses, and computer program products for transmitter residual carrier frequency offset compensation. The method may include receiving, at a reference user equipment, configuration for a positioning reference measurement from a network element. The method may also include estimating a transmission carrier frequency offset of the network element based on the positioning reference measurements. The method may further include transmitting the estimated transmission carrier frequency offset in a report to the network element.

A signal specification identification apparatus includes processing circuitry that estimates the transmission rate of a received signal, performs sampling frequency conversion on the received signal, calculates a probability corresponding to each of a plurality of candidates for a specification of the received signal, selects a candidate using the respective probabilities, and calculates reliability corresponding to a selected candidate, determines whether to output the selected candidate as an identification result or perform the sampling frequency conversion again, based on the reliability, and changes a parameter indicating the ratio of the sampling frequency conversion when it is determined that the sampling frequency conversion is to be performed again. Processing is repeated until the processing circuitry determines that the selected candidate as the identification result is to be output.

The present disclosure provides a method for estimating a frequency offset, including: extracting sampling points from an input signal according to preset intervals to obtain a plurality of groups of sampling points, with the preset intervals of the groups of sampling points being different; performing processes on a current sampling point and the groups of sampling points to obtain data of arguments of complex numbers corresponding to the preset intervals; and determining an estimation value of a frequency offset of a current input signal according to the data of arguments of complex numbers corresponding to the preset intervals. The present disclosure further provides an apparatus for estimating a frequency offset, an electronic device and a computer-readable medium.

A transceiver configured to: determine a reference frequency offset relative to a second transceiver based on double sided ranging; correct first and second portions of a packet received from a respective first and second antenna; and determine an angle of arrival of the packet based on corrected first and second portions and the reference frequency offset.

[FIG. 10]