The user devices in managed networks, such as 5G and 6G networks, are required to adapt their uplink transmissions to the base station’s resource grid, including the timing and frequency structure of the resource grid. Message-heavy legacy synchronization procedures can consume substantial resources. Therefore, a simpler, faster procedure is disclosed in which synchronization parameters are standardized where possible, timing signals are configured in minimal size where possible, and the user device collaborates with the base station to adjust the user device’s clock setting, clock rate, timing advance (to match the base station’s symbol boundaries), and Doppler correction (to match the base station’s subcarrier frequency), without exchanging data messages other than very brief timing signals. Such ultra-lean synchronization procedures may enable low-complexity synchronization in future high-frequency communications.

High-frequency communications in 5G and especially 6G will require precise synchronization of user devices with the base station, including periodically setting the user device clock time and clock rate to mitigate oscillator drift. The base station can assist user devices by periodically providing a timing signal containing a mid-symbol timestamp point, which is a signal that includes an abrupt change in phase or amplitude centered in the symbol-time. A receiver can analyze the timing signal and determine precisely the time of arrival of the timestamp point, and correct the receiver's clock to ensure that uplink messages will then arrive at the base station synchronized with the base station's resource grid. In addition, the base station can provide two timing signals in which the mid-symbol timestamp points are separated by a predetermined separation, thereby assisting the user devices in adjusting their clock rates.

A WTRU may receive downlink control information (DCI) indicating a start of a frame. The DCI may be received on a control channel, such as the Physical Downlink Control Channel (PDCCH) from an eNB, base station, AP, or other infrastructure equipment operating in a wireless communications system. The WTRU may decode the DCI and may determine a transmit time interval (TTI) duration, which may be expressed in terms of an integer number of basic time intervals (BTIs). The WTRU may determine a downlink (DL) transmission portion and assignment and an uplink (UL) transmission portion and UL grant based on the received DCI. Additionally, the WTRU may determine the start of the UL portion based on an offset (t.sub.offset). The WTRU may receive data in a DL portion of the frame and may transmit in an UL portion of the frame based on the determined UL grant and TTI duration.

A method for performing radio link monitoring comprises performing, by a user equipment (UE), a radio link monitoring (RLM) procedure with first RLM parameters; receiving, at the UE, a message including at least one second RLM parameter; identifying, by the UE, a difference between the first RLM parameters and the at least one second RLM parameter; and resetting, at the UE, at least one of the first RLM parameters in response to identifying the difference between the first RLM parameters and the at least one second RLM parameter. The method may configure the UE upon performing RLM by adapting the difference between the current RLM parameters and the future parameters, so that the UE behavior may become clear.

Methods, apparatus and systems for transmitting signal and channel information in a wireless communication are disclosed. In one embodiment, a method performed by a wireless communication node is disclosed. The method comprises: determining a first time domain position associated with a transmission of a first block according to a first configuration; and transmitting a second block at the first time domain position according to a second configuration, wherein the second configuration is different from the first configuration.

In a method for data transmission, delay jitter characteristics of service data packets during transmission of the service data packets are received. The delay jitter characteristics indicate changes in transmission delay of the service data packets. Whether jitter optimization is to be performed is determined by an application layer device according to the delay jitter characteristics and delay jitter requirements of the service data packets. First indication information is transmitted to a core network element when the jitter optimization is determined to be performed. The core network element is configured to start delay jitter optimization in response to the first indication information.

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a first user equipment (UE) may receive, from a second UE, a second synchronization signal at a reception time. The first UE may adjust a transmission time of a first synchronization signal, resulting in an adjusted transmission time, wherein the adjusted transmission time is based at least in part on the reception time of the second synchronization signal. The first UE may transmit the first synchronization signal at the adjusted transmission time. Numerous other aspects are described.

Systems and methods for quickly acquiring a PSS of a broadcast signal are provided. Such systems and methods include performing a time domain differential correlation on sections of the broadcast signal and identifying peak values in a summation of results of the time domain differential correlation. The systems and method also include performing frequency domain differential correlations between the frequency domain versions of the first section and the second section and identifying ones of maximum values of a ratio of output of the frequency domain differential correlations. Finally, the provided systems and methods include searching for the PSS in localized regions of the broadcast signal that are defined in the time domain by the preconfigured number of peak values and in the frequency domain by the ones of the maximum values of the ratio.

A WTRU may receive downlink control information (DCI) indicating a start of a frame. The DCI may be received on a control channel, such as the Physical Downlink Control Channel (PDCCH) from an eNB, base station, AP, or other infrastructure equipment operating in a wireless communications system. The WTRU may decode the DCI and may determine a transmit time interval (TTI) duration, which may be expressed in terms of an integer number of basic time intervals (BTIs). The WTRU may determine a downlink (DL) transmission portion and assignment and an uplink (UL) transmission portion and UL grant based on the received DCI. Additionally, the WTRU may determine the start of the UL portion based on an offset (t.sub.offset). The WTRU may receive data in a DL portion of the frame and may transmit in an UL portion of the frame based on the determined UL grant and TTI duration.

Uplink messages in 5G and 6G are expected to arrive at the base station in alignment with the base station's resource grid, at the proper time and frequency. Disclosed are lean procedures and compact timing signals that can enable user devices to maintain synchronization with a base station's resource grid. Shaped timing signals are disclosed that, when measured by a receiver, can indicate whether the receiver's clock is synchronized with the transmitter's clock, or is in disagreement, and in which direction, and by how much. The receiver thereby determines the clock error by amplitude measurements only, since the timing signal is configured to convert the timing error into a readily determined amplitude value, which the receiver can quantify using normal amplitude-demodulation procedures. The receiver's amplitude resolution corresponds to the time resolution achievable. No special time-measurement signal processing is required. No synchronization messages or other legacy overhead are required.