A wireless device receives access network information indicating an access network type. Based on the access network type, a non-access stratum (NAS) period is selected among: a first value associated with a geostationary earth orbit (GEO) non-terrestrial network (NTN) access network type; and a second value associated with a low earth orbit (LEO) NTN access network type. A NAS procedure is initiated by sending a NAS request message. A start of the NAS period is based on the sending. The NAS procedure is aborted based on an expiry of the NAS period.

A method for establishing a communication of the IP multimedia subsystem in local routing mode where user data are routed directly at one or more interconnected satellites, without passing through the ground, between two UE terminals connected to a regenerative satellite of a communication network comprising a satellite constellation. A session control function of the IMS core network interrogates a server linked to the satellite constellation with the information relating to the satellite access networks of the two terminals. The server is able to determine, by verification of an inter-satellite link between the regenerative satellites corresponding to the information relating to the satellite access networks of the two terminals, whether local routing of the user plane without passing through the ground is available to directly connect the two terminals are connected by link.

Embodiments include methods for radio link monitoring (RLM) by a user equipment (UE) in a combined terrestrial and satellite wireless communication network. Such methods include, during a discontinuity in a connection between a UE and a terrestrial network node (TNN), performing RLM of the connection based on a second configuration. Such methods also include, before and/or after the discontinuity, performing RLM of the connection based on a first configuration. The connection includes a first link between the UE and a satellite and a second link between the satellite and the TNN. The discontinuity includes a link switch in at least one of the first link and the second link. The RLM before, during, and after the discontinuity can include various first, second, and third operations, respectively. Embodiments also include complementary methods performed by a TNN, as well as UEs and TNNs configured to perform operations corresponding to such methods.

An efficient return channel spectrum utilization technique for communication systems supporting adaptive spread spectrum. Requests for bandwidth allocation using a spread factor are analyzed to determine if there are any channels capable of supporting the spread factor. The request is acknowledged if at least one channel is capable of supporting the request. Adjacent channels required to accommodate the requested spread factor are reserved, and additional bandwidth requests are allocated on non-reserved channels.

A method, a device, a terminal and a service device for determining satellite communication system parameters are provided. The method includes: obtaining gateway station information, according to an ephemeris information table or a system message; calculating feeder link information of a current communication link, according to the obtained gateway station information; and determining a satellite communication system parameter of the terminal according to the feeder link information.

This application relates to the field of communication technologies, and discloses a communication method and a communication apparatus, to resolve a problem of a poor interference suppression effect caused by closing an edge beam of a satellite. The method includes: A first satellite sends a first message to a second satellite. The first message includes information about a frequency reuse scheme. The information about the frequency reuse scheme includes basic unit information. The basic unit information includes central point locations and frequency information of at least N−1 beams. Herein, N is a frequency reuse factor of the first satellite. At least N−1 different pieces of frequency information exist in the frequency information that is of the at least N−1 beams and that is included in the basic unit information. In addition, N is a positive integer greater than or equal to 3.

A system includes antennas to receive satellite signals, modems for managing data received from the antennas, and a switching unit for managing the allocation and the transmission of the data from the various antennas to the various modems, the data from any one of the antennas being able to be allocated and transmitted to any one of the modems, the system thus being able to adapt the allocation of the data such that each modem is able to continue to receive data relating to signals transmitted by one and the same satellite upon a change of position of the antennas, thereby making it possible to maintain communication to one or more given satellite communication services.

MAC layer enhancements in protocol stacks of a user terminal of a satellite communication system such as a 5G based system. The MAC layer may include a scheduler that allows resource aggregation by allocating additional radio resources to users on one beam using carriers allocated to an adjacent beam. The MAC layer enhancements may also provide user terminals the ability to report their battery status to the scheduler which can then send signals to the user terminal that allow the terminal to shut down electronics to conserve power resources based on the battery status.

Systems, methods, and devices for random access to a communications network by a wireless transmit/receive unit (WTRU). In some implementations, the WTRU receives random access response (RAR) configuration information. The WTRU determines a time offset for a RAR window, based on a minimum round trip time (RTT) between the WTRU and a non-terrestrial network device. The WTRU determines a length of the RAR window. the WTRU monitors a physical downlink control channel (PDCCH) from the non-terrestrial network device during the RAR window based on the time offset and the length of the RAR window.

An information processing device calculates a communication available period for communication between a satellite station and an earth station on the basis of orbit information regarding the satellite station and location information regarding the earth station, and performs reservation processing for reserving a communication reservation period for the communication between the satellite station and the earth station, among reservation target periods selected from the communication available period.