1526 results about "Random-access channel" patented technology

The present disclosure relates to a communication technique and system for combining an IoT technology with a 5G communication system for supporting a higher data transfer rate than a 4G system. According to an embodiment of the present invention, a method of a terminal supporting subband non-overlapping full duplex (SBFD) in a wireless communication system may comprise the steps of: receiving time duplex division (TDD) resource configuration information and SBFD resource configuration information from a base station; determining respective indexes of first random access channel (RACH) occasions that are commonly valid in the TDD resource configuration information and the SBFD resource configuration information; and determining respective indexes of second RACH occasions that are invalid in the TDD resource configuration information and are valid in the SBFD resource configuration information.

Methods, apparatuses, and computer-readable medium for reducing signaling overhead for a RedCap UE are provided. An example method may include receiving, from a base station, a grant associated with a set of random access channel (RACH) resources, a first part of the set of RACH resources for a reduced capability report including a set of overlapping resources that overlaps with a second part of the set of RACH resources for a physical uplink shared channel (PUSCH) repetition request. The example method may further include transmitting, in the set of overlapping resources to the base station, one or more repetition requests or one or more repetition number indications.

A method of wireless communication performed by a user equipment (UE) includes receiving, from a base station (BS), a random access configuration associated with a plurality of random access occasions, wherein at least a first portion of the plurality of random access occasions is configured for PRACH message repetitions. The method further includes transmitting, to the BS based on the random access configuration, at least one random access communication, the at least one random access communication including a plurality of PRACH message repetitions in two or more of the plurality of random access occasions, wherein at least one of a random access occasion index associated with the at least one random access communication or the random access preamble indicates the at least one random access communication includes at least two PRACH message repetitions.

A method of transmitting a random access channel (RACH) by a user equipment (UE) in a wireless communication system is disclosed. The method includes receiving a synchronization signal block (SSB) on a first carrier among a plurality of carriers, determining a second carrier for transmitting the RACH among the plurality of carriers, and transmitting the RACH on the second carrier.

A method performed by a WTRU may include receiving a random access channel (RACH) configuration indicating a plurality of RACH occasions. The RACH occasions within respective subsets are frequency division multiplexed. The method includes receiving configuration information indicating at least one transmit power threshold and information indicating resources associated with a mode of operation, and receiving criteria for selecting a RACH occasion that defines a group of RACH occasions from at least one subset that overlap with at least one uplink subband. The method includes sending a preamble transmission using a calculated transmit power in a selected RACH occasion, wherein, on a condition the calculated transmit power exceeds the transmit power threshold, the selected RACH occasion is selected from the defined group of the plurality of RACH occasions that overlap with the at least one uplink subband.

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may transmit a message 1 (msg1) report message, of a four-step random access channel (RACH) procedure, identifying information associated with a plurality of synchronization signal blocks (SSBs), wherein the information includes a plurality of SSB indices associated with the plurality of SSBs. The UE may receive, based at least in part on transmitting the msg1 report message, a message 2 (msg2) update message, of the four-step RACH procedure, with an indication of a downlink beam associated with an SSB index of the plurality of SSB indices. The UE may transmit a response message, based at least in part on receiving the msg2 update message, indicating a confirmation of the SSB index indicated in the msg2 update message or indicating a reversion to a different SSB index.

During a random access (“RA”) procedure associated with a network node of a new radio (“NR”) communications network, a communication device can determine information associated with at least one of the communication device and a channel between the communication device and the network node. The communication device can further determine a number of physical RA channel (“PRACH”) transmissions to transmit to the network node prior to receiving a random access response as part of the RA procedure based on the information. The communication device can further transmit the number of PRACH transmissions to the network node as part of the RA procedure.

A wireless device is configured to receive information from a network node. The information indicates whether or not a medium access control, MAC, service data unit, SDU, for a signaling radio bearer, SRB, or data radio bearer, DRB, is to be received by the wireless device in the same MAC protocol data unit, PDU, as a MAC PDU carrying a random access success response message. This random access success response message indicates both a random access channel and an uplink shared channel payload were decoded successfully. In some embodiments, the wireless device is configured to receive a MAC PDU carrying the random access success response message, and to process the received MAC PDU based on the received information indicating whether a MAC SDU for an SRB or DRB is included in the received MAC PDU.

A method, network node and wireless device (WD) for a physical random access channel (PRACH) for subband full duplex operation are disclosed. According to one aspect, a wireless device configured to communicate with a network node is provided. The wireless device is configured to receive frequency domain configuration information and time domain configuration information indicating a plurality of subband full duplex, SBFD, symbols and a plurality of uplink-, UL-, only symbols in a time division duplex, TDD, configuration, and determine a validity of a random access channel, RACH, occasion, RO, based on whether a validity condition is met, the RO being positioned in at least one SBFD symbol of the plurality of SBFD symbols or in at least one UL-only symbol of the plurality of UL-only symbols.

A method may include a wireless device receiving resource control (RRC) messages comprising configuration parameters of a layer 1 / layer 2 triggered mobility (LTM) and a configured grant Type 1 for one or more physical uplink shared channel (PUSCH) transmissions of a random access channel (RACH)-less LTM cell switch. The method may also include receiving a medium access control (MAC) control element (CE) triggering an LTM cell switch procedure for the RACH-less LTM cell switch. The method may also include determining not to initiate a random access (RA) procedure based on the RACH-less LTM cell switch being ongoing. The method may also include, based on the RACH-less LTM cell switch being ongoing, not initiating the RA procedure. The method may also include transmitting, using the configured grant Type 1 and for the RACH-less LTM cell switch, a first PUSCH transmission of the one or more PUSCH transmissions.

An internet of things (IoT) non-terrestrial network (NTN) device user equipment (UE) is described. The UE includes receiving circuitry configured to receive narrowband physical random access channel (NPRACH) configurations including NPRACH resource configuration, repetition parameters, orthogonal cover code (OCC) multiplexing methods and OCC multiplexing factors. The UE also includes transmitting circuitry configured to select an NPRACH resource and randomly select an OCC index for an OCC multiplexing. The transmitting circuitry is further configured to transmit NPRACH preambles with a configured OCC multiplexing method and a multiplexing factor.

A terminal according to an aspect of the present disclosure includes: a control section that makes determination of repetition of a random access channel assuming that the repetition of the random access channel is necessary when a condition is met; and a transmission section that performs, upon the determination, the repetition of the random access channel to a base station in accordance with a configuration on the repetition of the random access channel from the base station.

Embodiments of the present application relate to methods and apparatuses of a mobility robustness optimization (MRO) mechanism for uplink (UL) coverage enhancement (CE) and network slicing procedures. According to an embodiment of the present application, a user equipment (UE) includes a processor and a transceiver coupled to the processor; and the processor is configured: to receive, via the transceiver from a network node, configuration information regarding at least one of a network slicing operation or an uplink (UL) transmission repetition operation; to perform a UL data transmission procedure or a random access channel (RACH) procedure based on the configuration information; and to transmit, via the transceiver to a serving cell, assistant information related to a failure of the UL data transmission procedure or a random access problem of the RACH procedure, wherein the assistant information is associated with at least one of the network slicing operation or the UL transmission repetition operation.

The disclosure relates to a 5G or 6G communication system for supporting a higher data transmission rate. According to one embodiment, a method for operating a user equipment (UE) in a wireless communication system may comprise receiving an L1 / L2 triggered mobility (LTM) medium access control control element (MAC CE) from a base station, determining whether the LTM MAC CE includes a timing advance (TA) value or a random access channel (RACH)-less handover indicator, and when the LTM MAC CE includes the TA value or the RACH-less handover indicator, performing a handover procedure to a target cell based on the TA value or the RACH-less handover indicator.

Methods, devices, and systems for providing early timing advance (TA) acquisition are provided. A radio resource control (RRC) configuration of the early TA acquisition is received from a base station. A PDCCH order to trigger a random access channel (RACH) procedure toward a candidate cell is received from the base station. The RACH procedure for the early TA acquisition is initiated based on the received RRC configuration and PDCCH order. A preamble with a calculated transmission power on the candidate cell is transmitted to the base station.

A wireless communication method includes receiving RA (Random Access) request preambles in one or more ROs (PRACH occasions) associated with a same SSB or associated with different SSBs, and transmitting corresponding one or more RA responses in response to the RA request preambles received by a BS.

A user equipment (UE) in a wireless communication system is provided. The UE includes a transceiver, and a controller coupled with the transceiver, and configured to receive, from a base station, first random access channel (RACH) configuration associated with a subband full duplex (SBFD) symbol and second RACH configuration associated with a non-SBFD symbol, and transmit, to the base station, a preamble on a first RACH occasion or a second RACH occasion, wherein the preamble is transmitted on the first RACH occasion in case that the first RACH occasion is valid.

Example embodiments of the present disclosure relate to resource selections of random access procedure. According to embodiments of the present disclosure, when a random access procedure is triggered for a certain feature combination, the terminal device determines the random access channel (RACH) partition to use based on a defined priority order of (RACH-partition) features whenever a RACH partition that would have matched the feature combination for which the RA procedure is triggered is not provided in the cell. The priority order could be pre-defined in the standards, provided by the Mobile Network Operators (MNO), or signaled dynamically by the network via system information or dedicated signaling (e.g., radio resource control (RRC) or medium access control (MAC) signaling). In this way, better resource selections may be achieved. Moreover, it does not need to configure resources for any possible combinations of features.

In general, the current subject matter relates to realizing random access channel layer-less (RACH-less) layer 1 / layer 2 triggered mobility (LTM). In some implementations, realizing RACH-less LTM can include receiving, at at least one LTM target cell of a base station, information indicative of whether handover (HO) of service for a user equipment (UE) currently being served by a serving DU of the base station can be a random access channel-less (RACH-less) HO to the at least one target cell or can be a RACH-based HO to the at least one target cell, and preparing the at least one LTM target cell, based on the information received at the at least one LTM target cell, for one of RACH-less HO and RACH-based HO.

A method and device are disclosed from the perspective of a first User Equipment (UE). In one embodiment, the UE receives a configuration of a threshold. Furthermore, the UE determines whether to initiate a procedure of small data transmission based on at least the threshold. In addition, the UE does not initiate the procedure of small data transmission if a radio condition of the UE is below the threshold.

Provided are a method and apparatus for determining a random access channel (RACH) resource type in subband full duplex (SBFD) of a wireless communication system. The method of the terminal may include receiving information on a maximum number of preamble transmissions through a subband full duplex (SBFD) symbol, transmitting at least one first preamble through a first random access channel (RACH) resource, and determining a second RACH resource configured on a non-SBFD symbol when a number of transmissions of the at least one first preamble exceeds the maximum number of preamble transmissions through the SBFD symbol.

Methods and apparatuses for early indication for initial access in full-duplex systems. A method for operating a user equipment (UE) includes receiving a system information block (SIB1) including configuration information, identifying, based on the configuration information, a random access channel (RACH) configuration, and identifying, based on the configuration information, an early access indication associated with a full-duplex operation. The method further includes determining to use a first random access transmission configuration if a condition for the early access indication associated with the full-duplex operation is met or a second random access transmission configuration if the condition is not met and transmitting a random access message using the determined first or second random access transmission configuration.

This application provides an information transmission method and a communication apparatus. The method includes: A terminal receives first indication information from a network device, where the first indication information indicates a first access threshold corresponding to a first synchronization signal; and the terminal determines, based on a value relationship between a local access value and the first access threshold, whether to send random access request information on a random access channel occasion corresponding to the first synchronization signal. This can improve resource utilization.

Wireless communication is performed by: receiving downlink control information including by a user equipment in an inactive state, a cyclic redundancy check scrambled by a radio network with at least one base-station with paging-Radio Network Temporary Identifier at least one user equipment, user equipment monitors paging message in inactive state and uses paging-Radio Network Temporary Identifier to decode reception of paging message, wherein the user equipment receives more than one random-access channel resources from the network and the indication of Small Data transmission and user equipment selects the random-access channel resources.

Methods and apparatus for transmitting a hybrid automatic repeat request acknowledgment (HARQ-ACK) are disclosed. A wireless transmit / receive unit (WTRU) may transmit a random access channel (RACH) message-A to a gNB. The WTRU may receive a RACH message-B from the gNB in response to the message-A. The message-B may comprise downlink control information (DCI). The WTRU may decode a physical downlink shared channel (PDSCH) based on the DCI. The WTRU may determine that contention resolution is successful. The WTRU may determine a resource for a physical uplink control channel (PUCCH). The WTRU may transmit a HARQ-ACK over the determined PUCCH resource. The WTRU may determine the resource for the PUCCH based on a PUCCH resource index. The PUCCH resource index may be based on a random access preamble index (RAPID) and a PUCCH resource indicator (PRI).

In an embodiment, a method, implemented in a WTRU, comprises receiving a first message comprising first configuration information indicating resources for a first type of random access channel occasions (ROs) and for a second type of ROs; determining whether to use the first type of ROs or the second type of ROs for a physical random access channel (PRACH) transmission based on a PRACH power; and transmitting the PRACH transmission in an RO of the determined ROs using the PRACH power.

The present application relates to the technical field of communications, and discloses a cell handover method and apparatus, a terminal, and a network side device. The cell handover method of embodiments of the present application comprises: a terminal receives a first message sent by a network side device, wherein the first message is used for triggering cell handover; and the terminal performs a first operation on the basis of the first message, wherein the execution of the first operation comprises any one of the following: when the first message satisfies a first condition, performing random access channel (RACH)-less cell handover, the first condition being a condition corresponding to the RACH-less cell handover; when the first message satisfies a second condition, performing contention-free random access (CFRA)-based cell handover, the second condition being a condition corresponding to the CFRA-based cell handover; and when the first message satisfies a third condition, performing contention-based random access (CBRA)-based cell handover, the third condition being a condition corresponding to the CBRA-based cell handover.

Certain aspects of the present disclosure provide techniques for association period based physical random access channel (PRACH) adaptation and activation. An example method, performed at a user equipment (UE), generally includes receiving signaling indicating adaptation of a first set of one or more random access channel (RACH) occasions (ROs), wherein the adaptation results in a second set of one or more ROs, determining an association period in which each synchronization signal block (SSB), of a set of SSBs, are mapped to at least one RO of the second set of ROs, and transmitting a RACH preamble in an RO of the second set, in accordance with the determined association period.

Wireless communications systems and methods are provided for validating a physical uplink shared channel (PUSCH) occasion defined for 2-step random access channel (RACH) in case of collisions. For example, the user equipment (UE) may determine whether a collision occurs between the PUSCH occasion for the 2-step RACH and any RACH occasion assigned for either 2-step RACH or 4-step RACH after receiving the RACH configuration or updates from the network. The UE may then exclude the PUSCH occasion from the resource pool for 2-step RACH when a collision occurs.

Systems and methods for two-step random access procedure are described. According to embodiments, a user equipment (UE) transmits a random access preamble on a random access channel. The UE also transmits data on an uplink data channel using a particular uplink data channel resource. The particular uplink data channel resource is selected by the UE based on the random access preamble.