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.

User terminal (20) receives a downlink resource including a data signal, a demodulation RS, and a correction RS via receiver (202), performs channel estimation using the demodulation RS via channel estimator (206) and channel corrector (207), and demodulates the data signal using a result of the channel estimation via demodulator and decoder (208). An MCS (CQI) index value and demodulation RS ports are associated with each CW of the data signal, and the correction RS is associated with any of demodulation RS ports associated with a high-quality CW corresponding to a highest MCS (CQI) index value. Channel estimator (206) and channel corrector (207) calculate a phase fluctuation amount using the correction RS associated with the demodulation RS port for the high-quality CW.

Techniques are described for peak-adaptive sampling demodulation for radiofrequency transceivers. For example, a tag input signal is received via an antenna, from which a clock input signal can be extracted. Multiple clock output signals can be generated responsive to the extracted clock input signal, such that each has a different respective phase. A multiphase selector can identify the one of the clock output signals that has the respective phase that is closest to the phase of the tag input signal and is best suited for sampling the peak of the tag input signal, accordingly. A single-path detector can generate a data output signal by using the identified clock output signal to sample the tag input signal, and the detector can filter and amplify the data output signal using small-signal devices.

Methods and devices for configuring an initial active downlink bandwidth part as part of an initial access procedure are provided. In one provided method, a base station broadcasts a synchronization signal block (SSB) that includes a control resource set CORESET) configuration index. The CORESET configuration index is one of a plurality of CORESET configuration indexes, each CORESET configuration index being associated with a respective configuration of a CORESET. Each configuration includes a CORESET frequency size, a CORESET time duration, and a frequency offset of the CORESET with respect to the SSB selected from a set of predefined frequency offsets. The initial active downlink bandwidth part is defined as having the same frequency location and bandwidth as the CORESET. The base station transmits, as part of a physical downlink control channel (PDCCH) within the CORESET, information indicating scheduling of remaining minimum system information (RMSI) in a physical downlink shared channel (POSCH).

A stable modulation-index Bluetooth (BT) transmitter circuit includes a baseband modulator circuit to generate a baseband BT signal. An intermediate frequency (IF) circuit adds a frequency offset to the baseband BT signal with a low IF and generates a modulated signal. A digital-to-analog converter (DAC) converts the modulated signal to an analog signal that is upconverted using a voltage controlled oscillator (VCO). The baseband frequency offset is subtracted from the corresponding radio-frequency (RF) signal by reducing the local oscillator (LO) frequency by the same amount. This has the effect of modulating the carrier leakage away from the center frequency of the transmitted BT signal. The resulting RF signal is transmitted to a receiver.

A technique for Bluetooth wireless communication is described. According to one aspect of the technique, Bluetooth data from a data source is received in a first wireless device through an antenna and a Bluetooth radio frequency transceiver thereof via a Bluetooth connection with the data source. The Bluetooth data is used to generate a modulation signal according to a narrowband orthogonal multi-carrier modulation technology. The modulation signal is transmitted to a second wireless device through the antenna and the Bluetooth radio frequency. The antenna and the Bluetooth radio frequency transceiver are time-multiplexed by the Bluetooth connection between the first wireless device and the data source, and the wireless connection between the first wireless device and the second wireless device. The described technique can be advantageously used for expanding the distance of Bluetooth wireless propagation of Bluetooth devices.

Disclosed are a signal transmission method and a base station the signal transmission method comprising: generating a phase data signal used for estimating phase noise in a downlink signal; and mapping the phase data signal on part of a resource region to which a general data signal to be transmitted to a terminal is mapped, and transmitting the general signal and phase data signal to the terminal, wherein the modulation order of the phase data signal is the same or lower than the modulation order of the general data signal.

A stable modulation-index Bluetooth (BT) transmitter circuit includes a baseband modulator circuit to generate a baseband BT signal. An intermediate frequency (IF) circuit adds a frequency offset to the baseband BT signal with a low IF and generates a modulated signal. A digital-to-analog converter (DAC) converts the modulated signal to an analog signal that is upconverted using a voltage controlled oscillator (VCO). The baseband frequency offset is subtracted from the corresponding radio-frequency (RF) signal by reducing the local oscillator (LO) frequency by the same amount. This has the effect of modulating the carrier leakage away from the center frequency of the transmitted BT signal. The resulting RF signal is transmitted to a receiver.

Systems and methods are provided for configuring an alignment between various resource grids. A base station transmits alignment information between a first resource grid or a first transmission using the first resource grid, and a second resource grid and a third resource grid. The first resource grid uses a first sub-carrier spacing (SCS) from a first set of SCSs, the second resource grid uses a second SCS from a second set of SCSs, the third resource grid uses a third SCS from the second set of SCSs. The base station transmits a synchronization sequence block (SSB) using the first resource grid, and the base station transmits a first physical downlink shared channel (PDSCH) in assigned resource blocks using at least one of the second resource grid and the third resource grid. A user equipment receives the alignment information, and determines the resource grids based on the alignment information so as to be able to receive the transmitted resource blocks.

Disclosed are methods and apparatuses for providing configurable reference signal timing difference (RSTD) search windows for positioning. In an aspect, an RSTD search window is configured based on a positioning reference signal (PRS) configuration. The RSTD search window is provided to the UE. A plurality of PRS is transmitted from a network entity to a user equipment (UE), each PRS having the PRS configuration. The plurality of PRS are transmitted in a subset that is less than all subcarriers over a given bandwidth.