A random access method includes sending a random access preamble to a base station on a first time domain resource, obtaining an index value of the first time domain resource, obtaining an index difference between the first time domain resource and a second time domain resource, obtaining an index value of the second time domain resource by adding the index value of the first time domain resource and the index difference, obtaining a random access radio network temporary identifier (RA-RNTI) based on the index value of the second time domain resource, receiving a random access response (RAR) from the base station, and descrambling a cyclic redundancy check (CRC) code of the RAR using the RA-RNTI.

A first UL or SL signal received by one UE from another UE is utilized to determine: a time of arrival for the first UL or SL signal relative to a reference time for the first UL or SL signal; a propagation time for the first UL or SL signal; a distance between the UE and the other UE determined based on at least the time of arrival for the first UL or SL signal, a first round trip time for transmissions between a base station and the other UE, and a second round trip time for transmissions between the base station and the UE; and an angle of arrival relative to a coordinate system of the UE for one of a second UL signal or a second SL signal from the other UE.

Systems, methods, and devices for sidelink positioning determination and communication can employ techniques including obtaining, at a first sidelink-enabled device, data from one or more data sources indicative of one or more criteria for using either round-trip time (RTT)-based positioning of a target node or single-sided (SS)-based positioning of the target node. The techniques also include selecting, with the first sidelink-enabled device, a positioning type from the group may comprise of RTT-based positioning and SS-based positioning, based on the data. The techniques also include sending a message from the first sidelink-enabled device to a second sidelink-enabled device, where the message includes information indicative of the selected positioning type.

A base station, a communication system and a time synchronization method between base stations are provided, which are capable of performing a time synchronization with another base station using a downlink signal of the other base station cell in which the own cell is located, without stopping transmission of the own base station even during operation. A base station 20 receives a downlink signal 255 that includes a downlink signal 11 including a synchronization signal transmitted from the other base station 10 and a downlink wraparound signal 22 transmitted from own base station 20, removes an interference of the wraparound signal from the downlink received signal, with respect to a predetermined subframe in which the downlink wraparound signal from own base station 20 interferes with the synchronization signal of the base station 10, among subframes of the downlink signal including the synchronization signal of the base station 10, performs a time synchronization processing with the base station 10 by detecting a synchronization signal timing of the base station 10 based on the downlink received signal from which the interference of wraparound signal is removed.

This application discloses a method for processing a round trip delay, a related apparatus, and a readable storage medium, and pertains to the field of communications technologies. The method includes: receiving a delay quantization parameter of a common round trip delay RTD, where the delay quantization parameter includes a first quantization parameter, and the first quantization parameter is used to indicate a height-related delay; and obtaining the common RTD based on the delay quantization parameter. The height-related delay is indicated by using the first quantization parameter, so that the common RTD is obtained based on the first quantization parameter.

This application provides a random access method and apparatus applicable to satellite communication. The method includes: obtaining a round-trip transmission latency t.sub.RTD of a signal between a terminal device and a satellite; obtaining a random access parameter based on the t.sub.RTD, where the random access parameter includes one or more of: a duration between a moment at which the terminal device sends a random access preamble and a moment at which the terminal device starts to receive a random access response RAR, a duration of a window in which the terminal device receives the RAR, a duration between a moment at which the terminal device stops receiving the RAR and a moment at which the terminal device sends the random access preamble again, and a subframe duration; and receiving, by the terminal device the RAR based on the random access parameter.

A system and method for stabilizing a reference clock of a client transceiver to a reference terminal in the presence of relative motion between the client transceiver and the reference terminal. In some embodiments, the method includes: transmitting, by the client transceiver, a probe packet to the reference terminal, receiving, by the client transceiver, the probe packet from the reference terminal, receiving, by the client transceiver, a first synchronization packet from the reference terminal, and adjusting the rate of the reference clock based on the time elapsed between: the transmitting, by the client transceiver of the probe packet to the reference terminal, and the receiving, by the client transceiver, the probe packet from the reference terminal; and based on the time of reception, by the client transceiver, of the probe packet.

UE parameter determination method and apparatus, storage medium and base station are provided. The method includes: determining a minimum round trip time between each UE in a cell and a satellite; determining frame information of a network-side uplink radio frame based on the minimum round trip time and frame information of a network-side downlink radio frame, where the minimum round trip time is a timing difference by which the network-side uplink radio frame lags behind the network-side downlink radio frame; and determining a UE parameter of each UE based on the network-side uplink radio frame and the network-side downlink radio frame, where UE parameter includes at least one of TA or K2. By the method, an NTN network can be supported on the premise that modification of software and hardware of a terrestrial network UE is minimized, thereby effectively avoiding extra maintenance cost of software and hardware.

Presented herein are systems and methods for detecting a boundary line crossing based on Round Trip Time (RTT) measured for wireless signals transmitted between and initiator wireless transceiver and a responder wireless transceiver deployed to form a straight boundary line. The initiator wireless transceiver transmits wireless probe signal(s) to the responder wireless transceiver, receives a wireless response signal transmitted by the responder wireless transceiver in response to the wireless probe signal(s), calculates an RTT combining a travel time of the wireless probe signal(s) and the travel time of the wireless response signal(s), compares the RTT to a reference RTT computed for a wireless probe signal and a corresponding wireless response signal transmitted in a clear straight transmission path while the boundary line is clear of obstacles and determines whether an object is blocking the straight transmission path based on a deviation of the RTT from the reference RTT.

Systems and methods for determining round trip time (RTT) includes a second node, which receives a first signal from a first node at a first time, determines a timing advance based on a first estimated channel response for the first signal, and transmits at a second time, a second signal to the first node, wherein the second time occurs after the first time by an amount of a pre-specified delay for RTT estimation minus the timing advance. The first node transmits the first signal to the second node at an initial time, receives the second signal from the second node, and determines a timing statistic from a second estimated channel response for the second signal, the timing statistic estimated at a third time. The first node determines the RTT as the third time minus the initial time minus the pre-specified delay for RTT estimation.