Abstract: In a first aspect, a communication control method is used in a cellular communication system. The communication control method includes receiving, by a relay node involved between a parent node and a child node, a flow control feedback message from the parent node or the child node. The communication control method includes executing, by the relay node, local rerouting to transfer a data packet to an alternative path, which is different from a path to the parent node or the child node transmitting the flow control feedback message, in response to a certain period elapsing after receiving the flow control feedback message.

Abstract: A base station allocates unmanned aerial vehicles (UAVs) preambles for use by UAV user equipment (UE) devices that are different from terrestrial preambles allocated for terrestrial UE devices. The UAV preambles can be allocated to different subscription levels, such that each UAV UE device can only use UAV preambles associated with the UAV UE device's subscription level. The UAV UE device transmits random access request message using the selected UAV preamble and the base station responds with a random access response message indicating whether access is granted to the UAV UE device. The base station can dynamically manage access to the base station by limiting the subscription levels that are associated with the UAV preambles.

Abstract: Cell selection in a New Radio-Unlicensed Standalone (NR-U SA) communication system is managed by allowing UE devices to avoid measurements of frequencies that are occupied. A base station (gNB) may indicate to the UE device frequencies that can be skipped or may allow the UE device to skip frequencies for a temporary period after the frequencies have been determined to be occupied.

Abstract: A communication control method used in a user equipment and user equipment that performs a predetermined data transmission in which uplink user data is transmitted during a random access procedure include transmission of a first message for the predetermined data transmission while in a predetermined RRC state in which an RRC connection is suspended to a base station. After transmitting the first message, a second message is received from the base station for maintaining the user equipment in the predetermined RRC state. A communication control method and base station include reception of a first message for the predetermined data transmission at the base station from a user equipment that is in a predetermined RRC state in which an RRC connection is suspended during a random access procedure. After receiving the first message, a second message is received for maintaining the user equipment in the predetermined RRC state.

Abstract: Handovers in a New Radio-Unlicensed Standalone (NR-U SA) communication system are managed by invoking one of a plurality of handover procedures based on conditions related to the communication device and channel status. One example of one of the plurality of handover procedures includes sending a handover command with an inactivity indicator to the UE device where the UE device transitions to an Inactive State (such as RRC_INACTIVE) in response to a handover failure (HOF) resulting from an occupied unlicensed channel. The UE device provides the I-RNTI allocated by the last serving gNB when resuming from the RRC_INACTIVE to the active state; thereby reducing the latency associated with a new connection from the idle mode. The target gNB uses the I-RNTI to retrieve the UE context from the last serving gNB.

Abstract: A remote user equipment (UE) device receives a sidelink (SL) discovery message from each of a plurality of candidate relay UE devices where each SL discovery message is transmitted using a discovery resource of a discovery resource pool of a plurality of discovery resource pools. Each discovery resource pool is allocated to a range of Reference Signals Received Power (RSRP) levels. Each relay UE device measures an RSRP level of a link to a destination and transmits the SL discovery message using a discovery resource from the discovery pool associated with the RSRP range containing the measured RSRP level. The remote UE device selects (or reselects) a relay UE device from the candidates based, at least partially, on the RSRP ranges of the links from the candidate relay devices to the destination.

Abstract: A user equipment, apparatus for controlling user equipment, and method performed by user equipment includes receiving a radio resource control (RRC) Release message from a base station included in a radio access network (RAN). The RRC Release message includes an indication causing the user equipment to transition from an RRC connected state to a specific state, the specific state being a state in which a RRC connection is suspended for the user equipment. The user equipment is caused to transition from the RRC connected state to the specific state in response to receiving the RRC Release message, perform a cell reselection operation when the user equipment is in the specific state, and perform, when the user equipment in the specific state, an operation of causing the user equipment to transition from the specific state to an RRC idle state in response to reselecting a cell not supporting the specific state.

Abstract: A communication control method according to a first aspect is a communication control method used in a cellular communication system. The communication control method includes performing, by a first relay node including a lower apparatus under the first relay node, handover from a first donor base station to a second donor base station together with the lower apparatus, and, upon completing the handover to the second donor base station, transmitting, by the first relay node and to the lower apparatus, a notification indicating completion of the handover.

Abstract: A communication control method according to a first aspect is a communication control method used in a cellular communication system. The communication control method includes transmitting, by a relay node that detects occurrence of a failure in a backhaul link between the relay node and a parent node of the relay node, a notification instructing execution of a conditional handover, and receiving, by a communication apparatus, the notification.

Abstract: A neighboring cell determines that uplink interference from an unmanned aerial vehicle (UAV) exceeds a first threshold at the neighboring cell. The neighboring cell transmits an uplink interference indicator to the UAV. In some examples, the UAV informs its serving cell of the uplink interference experienced by the neighboring cell. The serving cell can utilize information received from the UAV to make handover decisions or scheduling decisions for the UAV that caused the uplink interference. In other examples, the UAV can temporarily refrain from transmitting on at least some of its uplink resources or utilize different uplink resources for uplink data transmissions. In still other examples, the UAV can utilize downlink measurements to select which neighboring base station System Information Block messages should be monitored for an uplink interference indicator.

Abstract: A source user equipment (UE) device receives a neighbor list from each of a plurality of neighbor UE devices where each neighbor list identifies proximate UE devices that are within communication range of the neighbor UE device transmitting the neighbor list. The source UE device selects, from the plurality of neighbor UE devices, at least one candidate relay device for relaying destination device data to a destination UE device. The selection is at least partially based on the received neighbor lists. The destination device data and a relay indicator are transmitted to the at least one candidate relay device where the indicator indicates that the at least one candidate device is to transmit the destination device data to the destination UE device.

Abstract: A source user equipment (UE) device receives a neighbor list from each of a plurality of neighbor UE devices where each neighbor list identifies proximate UE devices that are within communication range of the neighbor UE device transmitting the neighbor list and including link information indicating a link quality of a communication link between the neighbor UE device and each proximate UE device in the neighbor list. The source UE device selects, from the plurality of neighbor UE devices, at least one candidate relay device for relaying destination device data to a destination UE device where the selection is at least partially based on the link quality information in the neighbor lists. The destination device data and a relay indicator are transmitted to the at least one candidate relay device. The indicator indicates that the at least one candidate device is to transmit the destination device data to the destination UE device.

Abstract: A relay (UE) receives, from a source UE device, a source transmission comprising destination device data and a relay indicator indicating that the destination device data is to be transmitted to a destination UE device. The relay UE device determines whether other communication data is pending transmission to another UE device over a device-to-device communication link. If other communication data is pending transmission, the relay UE device determines whether a destination data priority level of the destination device data is greater than another data priority level of the other communication data. The destination device data is transmitted to the destination UE device in accordance with the priority levels.

Abstract: The methods, devices, and systems discussed herein describe four different mechanisms (e.g., solutions) to assist a leader of a group of wireless communication devices in deciding when to switch between groupcast and unicast transmissions. In the first solution, the group leader may decide to initiate groupcast or unicast without considering the design of the Access Stratum (AS) layer link management. In the second solution, the group leader can determine whether to initiate unicast transmission based, at least partially, on feedback messages received from one or more other members of the group. In the third solution, the group leader has the option to simultaneously transmit groupcast and unicast transmissions towards the same user equipment devices (UEs). In the fourth solution, the group leader indicates to the groupcast-receiving UEs that the transmission is about to be switched from groupcast to unicast.

Abstract: A relay user equipment (UE) device transmits selected system information in a sidelink discovery message where the selected system information is a subset of system information received from a cell at the relay UE device. A remote UE device receiving the sidelink discovery message with the selected system information obtains at least system information for accessing the cell where such system information may not be available directly from the cell. The remote UE receiving select system information from each of a plurality of candidate relay UE devices manages relay selection/reselection at least partially based on the selected system information.

Abstract: User equipment, and an apparatus and method used in user equipment are perform a predetermined data transmission in which the user equipment transmits uplink user data when the user equipment is in an RRC inactive state. The user equipment, apparatus and method transmit a random access preamble for the predetermined data transmission to a base station during a random access procedure, and transmit an MSG 3 message together with uplink user data to the base station during the random access procedure. A base station performs a predetermined data transmission in which a user equipment transmits uplink user data when the user equipment is in an RRC inactive state, includes a receiver receiving a random access preamble for the predetermined data transmission during a random access procedure from the user equipment, and receives an MSG 3 message together with uplink user data from the user equipment during the random access procedure.

Abstract: Handovers in a New Radio-Unlicensed Standalone (NR-U SA) communication system are managed by invoking one of a plurality of handover procedures based on conditions related to the communication device and channel status. One example of one of the plurality of handover procedures includes sending a handover command with an inactivity indicator to the UE device where the UE device transitions to an Inactive State (such as RRC_INACTIVE) in response to a handover failure (HOF) resulting from an occupied unlicensed channel. The UE device provides the 1-RNTI allocated by the last serving gNB when resuming from the RRC_INACTIVE to the active state; thereby reducing the latency associated with a new connection from the idle mode. The target gNB uses the 1-RNTI to retrieve the UE context from the last serving gNB.

Abstract: A base station transmits a rate recommendation to a first user equipment (UE) device. The rate recommendation is to be used for a Voice over Long-Term Evolution (VoLTE) call between the first UE device and a second UE device. In some instances, the first UE device and the second UE device negotiate the rate to be used for the VoLTE call, based on the rate recommended by the base station. If the negotiated rate is supported by the base station and/or matches a supported codec rate, the UE devices implement the rate and provide rate feedback to the base station.

Abstract: A communication control method used in a mobile communication system, the mobile communication system providing a multicast broadcast service (MBS) from a base station to a user equipment, the communication control method including, by the base station, performing header compression processing in which transmission of header information is omitted, the header information being static information included in a header of an MBS packet, and transmitting a compressed MBS packet subjected to the header compression processing, and transmitting, by the base station, after starting transmitting of the compressed MBS packet, the header information separately from the compressed MBS packet.

Abstract: Provided is a communication control method used in a mobile communication system providing a multicast and broadcast service (MBS) from a base station to a user equipment and includes receiving, by the user equipment in an RRC connected state and from the base station, unicast signalling including an MBS configuration used for MBS reception, and performing, by the user equipment having transitioned from the RRC connected state to an RRC idle state or an RRC inactive state, the MBS reception by using the MBS configuration received in the RRC connected state.