1092 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.

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.

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 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.

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.

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.

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.

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.

A wireless communication method and / or apparatus is disclosed. The method comprises receiving, by a wireless communication terminal from a network node, configuration information for a handover procedure without a Random Access Channel, RACH procedure; initiating, by the wireless communication terminal, the handover procedure without a RACH procedure according to the configuration information; and transmitting, by the wireless communication terminal to a wireless communication node, uplink, UL, data for the handover procedure without a RACH procedure according to the configuration information.

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

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may identify a set of valid RACH occasions of a plurality of RACH occasions, wherein the set of valid RACH occasions includes one or more first valid RACH occasions on one or more uplink symbols and an uplink sub-band in a downlink symbol. The UE may identify a first set of synchronization signal block (SSB) indexes associated with the one or more first valid RACH occasions and a second set of SSB indexes associated with the one or more second valid RACH occasions. The UE may transmit a RACH message on a valid RACH occasion of the set of valid RACH occasions, the valid RACH occasion corresponding to an SSB index. Numerous other aspects are described.

A control method for a network-controlled repeater includes: determining that the repeater transmits a physical random access channel to the base station, in which the physical random access channel is configured to recover a control link between the repeater and the base station; and causing the repeater to cease forwarding a signal between the base station and a user equipment. Causing the repeater to cease forwarding the signal may include causing the repeater to cease forwarding the signal between the base station and the user equipment on all carrier components or selected carrier components.

Methods, systems, and devices for wireless communication are described. In some aspects, a network entity may allocate or configure multiple different quantities of random access channel (RACH) occasions and / or random access preambles, with each of the multiple different quantities of RACH occasions and / or random access preambles being associated with a respective synchronization signal block (SSB) index of a set of SSB indices. The network entity may allocate or configure a quantity of RACH occasions and / or random access preambles per SSB index based on a quantity of user equipments (UEs) served by the network entity in a direction associated with that SSB index. For example, the network entity may serve a coverage region associated with an SSB index and may allocate a quantity of RACH occasions and / or random access preambles for the SSB index based on a quantity of UEs within the coverage region.

Aspects of the present disclosure provide for managing random access channel (RACH) procedures in wireless communication systems. In some examples, a UE includes a processor, a transceiver communicatively coupled to the processor and configured to communicate with a scheduling entity in the wireless communication network, and a memory communicatively coupled to the processor. The processor is configured to receive a signal from a base station at the beginning of a fixed frame period during a two-step random access procedure, determine whether a resource for a transmission occasion overlaps one or more symbols located at an edge of the fixed frame period, and discard the resource for the transmission occasion at the UE when the resource overlaps the one or more symbols located at the edge of the fixed frame period.

Various aspects of the present disclosure relate to the implementation of certain conditions when allowing or facilitating physical random access (PRACH) preamble transmissions during sub-band full-duplex (SBFD) symbols. For example, a wireless communication system may implement limitations on which SBFD symbols and / or when certain SBFD slots / symbols may be associated with PRACH preamble transmissions (e.g., which RACH occasion (RO) of an SBFD slot / symbol).

A wireless transmit / receive unit (WTRU) may receive configuration information. The configuration information may include one or more of an indication of a set of estimation synchronization signal blocks (SSBs), a set of random access channel (RACH) occasions (ROs) configurations associated with the set of estimation SSBs, an indication of a set of actually transmitted SSBs, and / or a set of ROs configurations associated with the set of actually transmitted SSBs. The WTRU may receive an indication of allowed estimation SSBs including a subset of the set of estimation SSBs that are allowed to be used for a RACH transmission. The WTRU may determine a reference signal received power (RSRP) value for each estimation SSB and / or for each actually transmitted SSB. The WTRU may determine a (e.g., selected) SSB out of the set of estimation SSBs or the set of actually transmitted SSBs, for example for a RACH transmission.

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a network node may configure a set of energy harvesting classes associated with performing a four-step random access channel (RACH) procedure. The network node may perform the four-step RACH procedure based at least in part on an energy harvesting class of the set of energy harvesting classes. Numerous other aspects are described.

Various aspects of the present disclosure relate to receiving a random access channel (RACH) configuration message, where the RACH configuration message includes at least one of first RACH configuration definitions for use with slots of a physical RACH which include both non-overlapping uplink (UL) frequency resource portions and downlink (DL) frequency resource portions, and at least one of second RACH configuration definitions for use with slots of a physical RACH which includes an UL frequency resource portion. The physical RACH has multiple associated Synchronization Signal / physical broadcast channel Block (SSB) indexes, where the first RACH configuration defines at least one RACH occasion (RO) corresponding to each of the associated SSB indexes, which occurs in the non-overlapping UL frequency resource portions of the physical RACH slot. A physical RACH preamble is transmitted on a selected RO, which occurs in the non-overlapping UL frequency resource portions of the physical RACH slot.