In a wireless communication method, a terminal device obtains a first uplink (UL) alignment timer, where the first UL alignment timer corresponds to a first timing advance group (TAG), the first TAG corresponds to a first serving cell group, the first serving cell group comprises at least one serving cell, and the first UL alignment timer is used for UL synchronization maintenance for the at least one serving cell in the first serving cell group.

Method and apparatus for switching between SS-TWR and DS-TWR. The apparatus reserves resources for transmission of a first SL-PRS in a first time slot. The apparatus transmits, to a second UE, the first SL-PRS within the first time slot. The apparatus receives, from the second UE, a second SL-PRS at a second time based on the first time slot and a response time associated with transmission of the second SL-PRS in response to the first SL-PRS. The apparatus measures a time difference between the transmission of the first SL-PRS and reception of the second SL-PRS to determine if a third SL-PRS is to be transmitted to the second UE.

A method by a communication device for supporting a random access procedure in a wireless communication network. The communication device provides an indicator for indicating a presence of an initial access request by the communication device. The initial access request is part of the random access procedure. The indicator comprises a pre-defined synchronization sequence, wherein one of: the indicator comprises a first access burst extending over one time slot, wherein the first access burst comprises the pre-defined synchronization sequence, which is longer than 41 bits, and the indicator comprises a second access burst extending over two time slots, the second access burst comprising the pre-defined synchronization sequence, which is longer than 88 bits. The communication device transmits the indicator on a random access channel in uplink to a network node. The indicator indicates the presence to the network node of the initial access request.

The method of synchronizing data frames between 5G baseband processing stations by a global position system (GPS)-integrated local oscillator block control, including the following steps: step 1: synchronize the baseband processor's local oscillator block with the GPS's 1 pps (pulse per second) pulse and generate a 10 ms (millisecond) pulse from the local oscillator; step 2: use the 10 ms synchronous pulse sync monitor block to get the sync offset between this pulse and the GPS 1 pps pulse; step 3: use the control algorithm to reconfigure the local oscillator so that the 10 ms synchronous pulse can follow the 1 pps GPS pulse.

Embodiments include detection of physical events associated with a wireless network, where the detected physical events are associated with the measurable effects on radio signals between devices in the wireless network. The detected physical event and associated radio signal information is used to provide precise low cost time synchronization for a device in a network.

The apparatus may be a user equipment (UE). The apparatus receives a transmission of at least one of a plurality of first synchronization signals. The apparatus receives at least one repeat transmission of the at least one of the plurality of first synchronization signals. In an aspect, the transmission and the at least one repeat transmission are received in a same synchronization signal block.

A synchronization apparatus capable of reducing the effect of the fluctuations in synchronization signals that are caused when the synchronization signals are received through a network are provided. A synchronization apparatus (20) according to the present invention receives a synchronization signal transmitted from a synchronization signal source (10) through a network. The synchronization apparatus (20) includes a frequency synchronization unit (21) that performs frequency synchronization based on a received synchronization signal, and outputs a frequency synchronization signal, a phase synchronization unit (23) that performs phase synchronization based on a synchronization signal transmitted from the synchronization signal source (10) through a network, and outputs a phase synchronization signal, and a phase synchronization control unit (22) that generates an offset value by using a phase difference between the frequency synchronization signal and the phase synchronization signal, and corrects a phase of the frequency synchronization signal by using the offset value.

A wireless communication device can include an oscillator circuit. The oscillator circuit can include an oscillator and measurement circuitry coupled to the oscillator. The measurement circuitry can receive an output signal of the oscillator and measure oscillator error by comparing the output signal of the oscillator to a nominal frequency for an amount of time. The oscillator circuit can further include adjustment circuitry to adjust an oscillator frequency of the oscillator based on the measured oscillator error.

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may receive a synchronization signal block (SSB) transmitted using a single carrier quadrature amplitude modulation (SC-QAM) waveform, wherein the SSB has a uniform bandwidth allocation for each of a primary synchronization signal (PSS) included in the SSB, a secondary synchronization signal (SSS) included in the SSB, and physical broadcast channel (PBCH) data included in the SSB. The UE may perform initial channel access based at least in part on the SSB. Numerous other aspects are described.

This disclosure provides systems, methods, apparatus, and computer programs encoded on computer storage media, for relative timing drift correction for distributed multi-user transmissions. In one aspect, a first access point (AP) may receive a first signal from a second AP. The first signal may be associated with a channel sounding procedure to be performed substantially simultaneously by the second AP and the first AP. The first AP may then receive a second signal from the second AP, and prior to a substantially simultaneous transmission by the second AP and the first AP. The second signal may include timing information relative to the first signal. The first AP may determine a start time of the substantially simultaneous transmission at the first AP based on the timing information, and may initiate the substantially simultaneous transmission according to the determined start time.