Various solutions for time and frequency in non-terrestrial network (NTN) communications are proposed. An apparatus implemented in a user equipment (UE) obtains a center frequency and a reference time of a non-terrestrial network. The apparatus further obtains a feeder link delay of a feeder link between a network node and a satellite, and a service link delay drift rate of a service link between the apparatus and the satellite. Then, the apparatus performs an uplink frequency pre-compensation through calculating an uplink transmit frequency according to the center frequency, the reference time, the feeder link delay, and the service link delay drift rate.

This application provides a TA determining method and apparatus for a terminal device. After receiving a TA adjustment parameter sent by an access network device and determining that a TA of the terminal device needs to be adjusted, the terminal device determines a TA scaling factor, a subcarrier spacing parameter, and a first TA, to jointly adjust the first TA to obtain a second TA. ATA adjustment parameter k is added when the terminal device determines the second TA, so that an adjustable range of the TA is larger. Therefore, the TA may be applied to determining the TA of the terminal device when the terminal device communicates with a satellite base station. In this way, the terminal device can adjust the TA when movement of a device is caused by both the terminal device and the satellite base station.

Embodiments of the present disclosure relate to a centralized network device change procedure. A method comprises in response to a distributed network device being to be disconnected with a centralized network device and connected with a further centralized network device, transmitting an interface resuming request from a distributed network device to the further centralized network device, the interface resuming request being used for resuming an inactivated interface between the further centralized network device and the distributed network device, the terminal device is served by the centralized network device via the distributed network device; and in response to receiving, from the further centralized network device, a resuming status message indicating the interface is successfully resumed, activating the inactivated interface to complete the resume procedure. In this way, when a gNB-DU, which is located at the satellite and moves along with the satellite, moves from the coverage of a gNB-CU to the coverage of a new gNB-CU, a terminal device, which is served by a gNB-CU via a gNB-DU, will keep the connection with the gNB-CU, such that the connectivity of the accessed terminal device will be maintained and meanwhile the signalling overhead for interface configuration will be saved.

A user equipment (UE) is described. The UE includes receiving circuitry configured to receive signaling that includes a configuration for a configured grant (CG) physical uplink shared channel (PUSCH) in a non-terrestrial network (NTN). The receiving circuitry is also configured to receive signaling that includes first information to indicate whether Hybrid Automatic Repeat Request N(HARQ) feedback is disabled for the CG PUSCH. The receiving circuitry is further configured to receive signaling that comprises second information to indicate a timing offset for the CG PUSCH. The UE also includes transmitting circuitry configured to transmit the CG PUSCH based on the configuration and the second information. The UE further includes a processor configured to flush a data CN buffer of the CG PUSCH based on the first information.

A method and system for sharing frequency spectrum with multiple networks includes selecting a first geographical coverage area served by a first base station associated with a first network. The first base station is configured to utilize a predetermined frequency spectrum. A second base station, associated with a different network, that is operating within the first geographical coverage area is identified. Frequency resources from the predetermined are subsequently allocated to the second base station.

Approaches for wireless telecommunications systems (e.g., satellite systems), that employ beams that move in a pattern to increase the coverage area of the beams, are provided. A wireless telecommunications apparatus comprises an antenna configured to generate communications beams for providing data communications services over a respective coverage area on the surface of the Earth. The apparatus further comprises a processor configured to control each of at least one of the communications beams to move its coverage area in a respective pattern over a respective period of time. Further, a method comprises generating, via a wireless telecommunications apparatus, communications beams, wherein each beam provides data communications services over a respective coverage area on the surface of the Earth, and controlling each of at least one of the communications beams to move its coverage area in a respective pattern of movement over a respective period of time.

A disclosure of the present specification provides a terminal which uses a frequency band of a mobile satellite service for LTE/LTE-A. The terminal comprises: a first duplexer for separating a transmitted signal and a received signal in band 1 defined in long term evolution (LTE)/LTE-Advanced; a second duplexer for separating a transmitted signal and a received signal in new band 65 which was a mobile satellite service (MSS) band and now is allocated for the terrestrial service; and a selection switch for selecting one of the first duplexer and the second duplexer. Herein, when only band 1 is configured and used, only the first duplexer may be operated by the selection switch. In contrast, when new band 65 is configured and used, wherein the configured band does not overlap the range of band 1, and when new band 65 is configured and used, wherein the configured band overlaps the range of band 1 for carrier aggregation, only the second duplexer may be operated by the selection switch.

Various arrangements for dynamically adjusting physical resource block (PRB) usage on a cellular network are presented. A primary entity may be determined to be exercising its priority to spectrum overlapping PRBs used by the cellular network. A frequency band being used by the primary entity based on measuring the signal strengths of wireless transmission by the primary entity can be determined. Subcarriers of the PRBs are identified that overlap the frequency band. A predefined Physical Random Access Channel (PRACH) format can be selected based at least in part on the identified subcarriers. A predefined Physical Uplink Control Channel (PUCCH) format can be selected based at least in part on the identified plurality of subcarriers.

A method for wireless communication by a user equipment (UE) includes modulating a symbol stream onto at least one subcarrier to generate an uplink signal in a frequency domain for transmitting to a receiver in a non-terrestrial network. The method also includes applying an amount of phase rotation to the at least one subcarrier in the frequency domain. The method further includes transforming the uplink signal from the frequency domain into a time domain uplink signal. The method includes transmitting the time domain uplink signal to the receiver, after applying the phase rotation to the at least one subcarrier.

Systems and methods are disclosed for random access in a wireless communication system such as, e.g., a wireless communication system having a non-terrestrial (e.g., satellite-based) radio access network. Embodiments of a method performed by a wireless device and corresponding embodiments of a wireless device are disclosed. In some embodiments, a method performed by a wireless device for random access comprises performing an open-loop timing advance estimation procedure to thereby determine an open-loop timing advance estimate for an uplink between the wireless device and a base station. The method further comprises transmitting a random access preamble using the open-loop timing advance estimate. In this manner, random access can be performed even in the presence of a long propagation delay such as that present in a satellite-based radio access network. Embodiments of a method performed by a base station and corresponding embodiments of a base station are also disclosed.