This document discloses a solution for synchronizing a terminal device to a network clock. According to an aspect, a method comprises as performed by the terminal device: receiving a control message from at least one access node, the control message comprising a first clock value indicating a transmission time of the control message; determining a geographical location of the terminal device and a geographical location of the at least one access node; computing, on the basis of the geographical locations of the terminal device and the at least one access node and further on the basis of the first clock value transmission time of the control message, a second clock value indicating a reception time of the control message at the terminal device; and updating a clock of the terminal device by using the second clock value.

Appropriate timing control is realized in accordance with propagation delay between a terminal and a base station. This terminal includes: a control unit that controls a transmission timing on the basis of first information relating to control of transmission timing of signals in a transmission increment of the signals, and second information relating to control of transmission timing in a finer increment than in the transmission increment; and a wireless transmission unit that performs signal transmission on the basis of control of the transmission timing by the control unit.

An operation method of a terminal in a communication system may comprise: receiving, from a satellite, transmission timing information including information on a first transmission timing of a first SSB of each of at least one local cell and information on second transmission timings of second SSBs of sub-cells belonging to each of the at least one local cell; identifying the first transmission timing of the first SSB and the second transmission timings of the second SSBs based on the transmission timing information; attempting to receive the second SSBs when the first SSB is received at the first transmission timing; acquiring cell access information from the second SSBs by receiving the second SSBs; and accessing the satellite by using the acquired cell access information.

A cooperative wireless system using a multicast protocol to facilitate coordinating coherent addition and subtraction of wireless signaling or other beams originating from a plurality of antenna units at a target location is contemplated. The system may utilize multicast-based regulation and distribution of transmission control parameters necessary for the antenna units to synchronize the wireless signaling in a manner sufficient to enable the coherent addition and subtraction thereof at the target location.

A communication method and apparatus. A terminal device determines, based on first information received from a first network device, that a second network device has first time information, where the first time information is time information having precision that is higher than precision of second time information of the first network device. The terminal device obtains the first time information of the second network device based on the first information. The terminal device obtains high-precision time information to improve communication reliability.

A wireless device may include a selection processor configured to process selection information to set a duration of a selection period and to start the selection period, a receiver configured to receive a synchronization initiation signal, and a transmitter configured to transmit a synchronization initiation signal after the selection period has expired if the receiver has not received a synchronization initiation signal during the selection period.

A base station that includes a memory for storing computer readable code and a processor operatively coupled to the memory is provided herein. The processor is configured to transmit, to a terminal apparatus, information associated with communication delays predicted for communication between the base station and the terminal apparatus. The terminal apparatus acquires the information associated with the communication delays from the base station.

Disclosed are techniques for determining a position of a user equipment (UE). A differential round-trip-time (RTT) based positioning procedure is proposed to determine the UE position. In this technique, the UE position is determined based on the differences of the RTTs between the UE and a plurality of base stations. The differential RTT based positioning procedure has much looser inter-gNodeB timing synchronization requirements than the OTDOA technique and also has much looser group delay requirements than traditional RTT procedures.

Various arrangements are presented for using an estimated timing advance for user equipment communications. A location of an instance of user equipment may be determined. An estimated distance between the user equipment and a communication satellite may be determined using the determined location of the user equipment and an estimated satellite location. An estimated timing offset using the calculated estimated distance may be determined. An uplink data frame may be transmitted by the user equipment to the satellite such that a timing of transmission of the uplink data frame is based on the calculated estimated timing offset.

A method of transmitting the reference signal includes: obtaining a plurality of candidate transmission positions of a reference signal according to an initial candidate transmission position of the reference signal, where the plurality of candidate transmission positions include the initial candidate transmission position; performing a channel detection before the reference signal is transmitted; and if channel idle is detected, transmitting the reference signal at a corresponding candidate transmission position, wherein reference signal position information carried by the reference signal comprises a reference signal index corresponding to the initial candidate transmission position and an offset between a current candidate transmission position and the initial candidate transmission position.