An Integrated Access and Backhaul (JAB) node incorporates two functions, a so-called “base station” function and a so-called “mobile terminal” function. In order to limit the interferences between base stations, all IAB nodes in the same network must be synchronised with one another. In order to ensure this synchronisation, each IAB node may use a time shift value transmitted by its parent node. However, since an IAB architecture is an arborescent architecture, errors in measuring an estimated time shift value for a given IAB node have repercussions on the measurements of estimated time shift values for its child node and so on. Accordingly, the “base station” function of a child IAB node is not activated as long as a time shift value determined by its parent node does not meet a synchronisation criterion.

Embodiments of the present disclosure provide a time service method, a terminal device, and a network device. The method includes: determining, by a terminal device, a first moment of a first downlink message, and determining a second moment of the first downlink message; determining, by the terminal device, a third moment of a first uplink message, and determining a fourth moment of the first uplink message; and determining, by the terminal device, a time offset between the terminal device and the network device based on the first moment, the second moment, the third moment, and the fourth moment. According to the method provided, a time service error is effectively reduced.

Various aspects of the disclosure relate to communication using a data unit that includes a payload with synchronization information. In some aspects, a first apparatus may transmit a data unit that includes at least one synchronization symbol in the payload. A second apparatus that receives the data unit may thereby recover synchronization information from the data unit even if interference at the second apparatus prevents the second apparatus from recovering synchronization information in a preamble of the data unit. In some aspects, the second apparatus may determine, based on information in the at least one synchronization symbol, whether and/or when to conduct a spatial reuse transmission. In some aspects, the second apparatus may determine, based on information in the at least one synchronization symbol, an amount of time to defer transmission.

In an aspect, a communications node (e.g., TRP or UE) obtains (e.g., measures) timing group delays associated with different positioning procedures to determine time drift information, and reports the time drift information to an external entity for position estimation.

According to one embodiment, an electronic apparatus controls an operation of a control target device. The electronic apparatus is configured to generate a first timing signal, to delay the first timing signal by a first time and to generate a second timing signal for defining a transmission timing of control data related to control of the operation of the control target device, to transmit a data signal including the control data based on the second timing signal, to receive the data signal and to generate a third timing signal for a notification of reception of the data signal, and, to generate a fourth timing signal indicating a control timing of the control target device based on the control data, based on the third timing signal.

Disclosed are systems, devices and methods for transmission of messages between wireless transceiver devices including fields representing values such as, for example, a range between devices, time of transmission of a message or time of receipt of a previous message. In particular embodiments, message may also comprise fields to express a maximum error in values representing range, time of transmission of a message or time of receipt of a previous message.

Example synchronization signal sending and receiving methods and apparatus are described. In one example method, a terminal device determines a target frequency resource. A frequency domain position of the target frequency resource is determined based on a frequency domain position offset and a frequency interval of synchronization channels. The terminal device receives a synchronization signal by using the target frequency resource.

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.

In some embodiments, a network node (e.g., a base station) collects information pertaining to components that form a Maximum Received Timing Difference (MRTD). For instance, the network node determines TAE. The network node then evaluates, for a particular UE, whether a certain MRTD requirement (MRTDR) for a specific coordinated service (CS) can be fulfilled. If the requirement can be met, then the network node may initiate the specific CS for the UE (or continue providing the CS), and if the requirement cannot be met, then the network node may stop or modify the CS for the UE.

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.