Abstract: Systems and methods are disclosed herein for enabling a User Equipment (UE) to perform cell quality derivation in a wireless communication network utilizing parameters from an appropriate measurement object. In some embodiments, a method of operation of a UE to perform cell quality derivation in a wireless communication network includes the UE receiving, via Radio Resource Control (RRC) signaling, a measurement configuration that includes a list of measurement objects. The UE receives a serving cell configuration including frequency information that specifies an absolute frequency of a Synchronization Signal block (SSB) corresponding to a serving cell. The UE selects a measurement object in the list of measurement objects that specifies an SSB frequency having a same value as the specified absolute frequency.

Abstract: Systems and methods for Semi-Persistent Sounding Reference Signal (SP SRS) resource activation or deactivation are disclosed. In some embodiments, a method of operation of a wireless device in a cellular communications network comprises receiving, from a network node, a Medium Access Control (MAC) Control Element (CE). The MAC CE comprises an indication of a SP SRS resource set to be activated or deactivated and information that indicates a spatial relation for the SP SRS resource set to be activated or deactivated. In this manner, a MAC CE for SP SRS resource set activation or deactivation is provided in a manner that gives spatial relation information in an efficient and flexible manner.

Abstract: Embodiments include methods for operating a user equipment (UE) in a non-terrestrial network (NTN) that utilizes one or more polarization modes for serving one or more cells. Such methods include sending, to a network node, an indication of one or more polarization capabilities of the UE. Such methods also include transmitting and/or receiving one or more signals or channels in a first cell of the NTN according to the indicated polarization capabilities of the UE. In some embodiments, the indicated polarization capabilities of the UE include: a UE type; one or more polarization modes supported by the UE; a polarization correspondence between uplink and downlink signals that is supported by the UE; and/or a list of antenna panels supported by the UE and polarization modes supported by the antenna panels. Other embodiments include complementary methods for operating network nodes, and UEs and network nodes configured to perform such methods.

Abstract: Systems and methods for supporting random access for wireless devices have different levels of random access pre-compensation and/or Global Navigation Satellite System (GNSS) capabilities are disclosed. In one embodiment, a method performed by a wireless device comprises obtaining two or more random access configurations for two or more wireless device classes that support different levels of pre-compensation for random access, have different GNSS capabilities, or both. The method further comprises selecting a random access configuration to be used by the wireless device from the two or more random access configurations. In this manner, random access is tailored to the capabilities of the wireless device.

Abstract: Systems and methods related to cell selection based on random access channel pre-compensation features supported by a wireless device are disclosed. In one embodiment, a method performed by a wireless device comprises obtaining information that indicates one or more random access channel pre-compensation features required for wireless devices to select a cell. The method further comprises making a decision as to whether the wireless device is permitted to select the cell based on the information and one or more random access channel pre-compensation features supported by the wireless device and performing one or more actions in accordance with the decision.

Abstract: Systems and methods for activating a Semi-Persistent (SP) Zero Power (ZP) Channel State Information Reference Signal (CSI-RS) are provided. In some embodiments, a method performed by a wireless device includes for activating SP ZP CSI-RS includes receiving, from a network node, a control message that indicates the activation of one or more SP ZP CSI-RS resources; and activating, based on the control message, the one or more SP ZP CSI-RS resources. In this way, ZP CSI-RS may be used for rate matching around other wireless devices and a SP ZP CSI-RS resource may be activated without activating any Non-Zero Power (NZP) CSI-RS, CSI-Interference Measurement (CSI-IM), or CSI reporting for the wireless device.

Abstract: According to some embodiments, a method performed by a wireless device for handover in a non-terrestrial network (NTN) from a source cell to a target cell comprises receiving a conditional handover configuration for one or more potential target cells. The conditional handover configuration comprises a condition for handover comprising a timing advance threshold value for each of the one or more potential target cells. The method further comprises determining that a timing advance between the wireless device and one of the one or more potential target cells is less than or equal to the timing advance threshold and based on the determination, performing a handover to the target cell.

Abstract: 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.

Abstract: Embodiments include methods performed by a second network node in a wireless communications network that includes a first network node, the second network node, and a third network node. Such methods include receiving, from the first network node, a configuration comprising a pattern indicative of whether or not each of a plurality of Synchronization Signal Block (SSB) transmissions, that are configured based on a nominal timing, are actually transmitted by the third network node according to the nominal timing. Such methods include, based on the received configuration, managing transmission and/or reception configurations for one or more of the following: one or more cells served by the second network node; and one or more UEs served by the second network node via the one or more cells. Other embodiments include second network nodes configured to perform such methods.

Abstract: A method for updating a tracking area in a non-terrestrial network comprises determining, at a network node, that a current tracking area in a non-terrestrial network is expiring; determining, at the network node, at least one target tracking area in the non-terrestrial network; and broadcasting, to at least one user equipment in the at least one target tracking area, system information comprising information of the at least one target tracking area. The target tracking area is determined based on a preconfigured mapping which comprises at least one target tracking area code corresponding to a cell identity of a target network node within a period of time or based on a movement of a satellite.

Abstract: In certain embodiments, a wireless device obtains one or more NTN-related metrics for each of a plurality of cells in a non-terrestrial network and selects a cell for camping based at least in part on the one or more NTN-related metrics. The one or more NTN-related metrics comprise: a geographical distance between the wireless device and a reference point; a distance between the wireless device and the one or more satellites serving each cell; an RTT offered by the one or more satellites serving each cell; RTT variations in each cell; a requirement to pre-compensate the RTT by means of GNSS measurements; a velocity of the satellite serving each cell; an angle of elevation between the device and the satellite(s) serving each cell; a Doppler shift induced by the satellite serving each cell; a tracking area code broadcasted by the cell; and/or a signal strength/quality offset.

Abstract: A method performed by a first network node (101) for enabling a second feeder link (132) to be established between a second network node (102) and an airborne or orbital communication node (110) in non-terrestrial communications network (100) to handle wireless devices (121) being served by the airborne or orbital communication node (110) is provided. The first network node (101) is handling the wireless devices (121) served by the airborne or orbital communication node (110) over a first feeder link (131) between the first network node (101) and the airborne or orbital communication node (110). The method comprises determining (701) that the wireless devices served by the airborne or orbital communication node (110) are to be handled by the second network node (102) over the second feeder link (132). Also, the method comprises initiating (702) the second feeder link (132) to be established between the second network node (102) and the airborne or orbital communication node (110).

Abstract: One aspect of the disclosure provides a method performed by a wireless device for performing handover from a source network node to a target network node. The method comprises: obtaining (1402) an indication of a round-trip time for transmissions to the target network node; initiating (1406) access to the target network node; and, subsequent to initiating access to the target network node, transmitting (1408) data to or receiving (1408) data from the source network node for a time window following initiation of access to the target network node. The time window has a duration of at least the round-trip time for transmissions to the target network node.

Abstract: According to some embodiments, a method performed by a wireless device comprises: determining geographical location information of the wireless device with respect to each cell of a plurality of cells; adjusting a cell reselection ranking for the plurality of cells based on the geographical location information for the plurality of cells; selecting a cell from the plurality of cells based on the adjusted ranking; and camping on the selected cell.

Abstract: Methods performed by base stations and wireless devices for reducing RSRP and/or RSRQ measurements are disclosed. A method performed by a base station comprises indicating to a wireless device whether or not to perform cell selection and/or reselection measurements based on certain criteria. A method performed by a wireless device comprises determining whether or not to perform cell selection and/or reselection measurements based on certain criteria. Also disclosed are base stations and wireless devices configured to perform the methods.

Abstract: A system, method and non-transitory computer readable media for facilitating reduced signaling load with respect to UE location reporting in a non-terrestrial network (NTN) environment (100) interoperable with one or more terrestrial cellular communications networks. In one embodiment of an index-based location reporting scheme, a UE (105, 1200) may receive (402) a list of reference locations from a network node (1000, 1100), each identified with an index. Responsive to receiving the list of reference locations, the UE (105, 1200) may report to the network node (1000, 1100) an index or a subset of indices of one or more reference locations that match a specific reporting criterion. In an example implementation, reporting of index-based location information by the UE (105, 1200) may be configurably triggered, e.g., periodically or in response to the occurrence of a particular event, condition, etc.

Abstract: Systems and methods are disclosed herein for selectively deactivating (partially or fully) Hybrid Automatic Repeat Request (HARQ) mechanisms in a cellular communications system. Embodiments disclosed herein are particularly well-suited for adapting HARQ mechanisms for non-terrestrial radio access networks (e.g., satellite-based radio access networks). 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 deactivating HARQ mechanisms comprises receiving, from a base station, an explicit or implicit indication that HARQ mechanisms are at least partially deactivated for an uplink or downlink transmission. The method further comprises determining that HARQ mechanisms are at least partially deactivated for the transmission based on the indication and transmitting/receiving the transmission with HARQ mechanisms at least partially deactivated.

Abstract: Methods and apparatus for obtaining a frequency offset corresponding to a Doppler shift of transmission and/or reception frequencies between a wireless device and a network node. In one embodiment a method is performed by a wireless device for operating in a non-terrestrial network, NTN, the NTN having at least one network node and a communication satellite, wherein the at least one network node is one of a terrestrial base station and a satellite base station or satellite gateway, the method includes obtaining a frequency offset corresponding to a Doppler shift of transmission and/or reception frequencies between the wireless device and the network node and applying the frequency offset to an uplink transmission to the network node.

Abstract: A wireless device (14) is configured for use in a wireless communication system (10). The wireless device (14) configures a number of parallel hybrid automatic repeat request, HARQ, processes (18) as being available for use. The wireless device (14) discontinuously monitors a downlink control channel (20), including monitoring the downlink control channel (20) during an active time (24) that is based on how many of the configured number of parallel HARQ processes (18) are used.

Abstract: Embodiments of a method performed by an Integrated Access and Backhaul (IAB) node to perform initial cell access in a cellular communications network and corresponding embodiments of an IAB node are disclosed. In some embodiments, the method performed by the IAB node comprises detecting a Synchronization Signal/Physical Broadcast Channel Block (SSB) of a cell and reading system information comprising a value of a parameter from the SSB. The method further comprises determining that the value of the parameter is a predefined value that serves as an indication to IAB nodes that additional system information is present on the cell and searching for the additional system information in accordance with the value of the parameter. In some embodiments, the predefined value of the parameter serves as an indication to one or more other types of nodes that additional system information is not present on the cell.