Random access opportunity selection for reduced capability user equipment - Patents.com

Abstract

Methods, systems, and devices for wireless communications are described. The described techniques relate to improved methods, systems, devices, and apparatuses that support random access opportunity (RO) selection for reduced capability (RedCap) user equipment (UE). A RedCap UE operating in half-duplex mode may use the techniques described herein to efficiently select an RO in which to transmit a random access preamble based on the duration between the last received downlink transmission and the RO meeting a threshold duration. The UE may receive system information that maps a set of synchronization signal blocks (SSBs) to a set of ROs. The UE may then select an RO from the set of ROs in which to transmit a random access preamble such that the UE has sufficient time to transition from a receive mode to a transmit mode to transmit the random access preamble.

Description

[Technical field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This patent application claims priority to International Patent Application No. PCT / CN2021 / 102348 to Lei et al., entitled "RANDOM-ACCESS OCCASION SELECTION FOR REDUCED-CAPABILITY USER EQUIPMENT," filed on June 25, 2021, assigned to the assignee of this application, and expressly incorporated by reference in its entirety into this specification.

[0002] The following relates to wireless communications, including random access opportunity selection for reduced capability user equipment. [Background technology]

[0003]

[0003] Wireless communication systems are widely deployed to provide various types of communication content, such as voice, video, packet data, messaging, broadcasts, and the like. These systems may be capable of supporting communication with multiple users by sharing available system resources (e.g., time, frequency, and power). Examples of such multiple-access systems include fourth-generation (4G) systems, such as Long-Term Evolution (LTE), LTE-Advanced (LTE-A), or LTE-A Pro systems, and fifth-generation (5G) systems, sometimes referred to as New Radio (NR) systems. These systems may employ techniques such as code division multiple access (CDMA), time division multiple access (TDMA), frequency division multiple access (FDMA), orthogonal FDMA (OFDMA), or discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-S-OFDM).

[0004]

[0004] A wireless multiple-access communication system may include one or more base stations or one or more network access nodes, each simultaneously supporting communication for multiple communication devices, sometimes known as User Equipment (UE). In some wireless communication systems, a UE may use a random access procedure to establish or re-establish a connection with a base station. Improved techniques for supporting random access procedures between a UE and a base station may be desired. Summary of the Invention

[0005]

[0005] The described techniques relate to improved methods, systems, devices, and apparatuses supporting random-access occasion (RO) selection for reduced-capability (RedCap) user equipment (UE). A RedCap UE operating in a half-duplex mode may use the techniques described herein to efficiently select an RO in which to transmit a random access preamble based on the duration between the last received downlink transmission and the RO satisfying a threshold duration. The UE may receive system information that maps a set of synchronization signal blocks (SSBs) to a set of ROs. The UE may then select an RO from the set of ROs in which to transmit a random access preamble such that the UE has sufficient time to transition from a receive mode to a transmit mode to transmit the random access preamble. These techniques may enable a half-duplex RedCap UE to efficiently perform a random access procedure to establish or re-establish a connection with a base station.

[0006] A method for wireless communication in a UE is described. The method may include receiving a message including a plurality of mappings of a respective set of synchronization signal blocks to a respective set of random access channel opportunities. The method may include receiving one or more synchronization signal blocks of the set of synchronization signal blocks, the set of synchronization signal blocks being identified from the respective set of synchronization signal blocks according to one mapping of a plurality of mappings determined at least in part based on a capability of the UE, the set of synchronization signal blocks being associated with a set of random access channel opportunities. The method may include transmitting a random access preamble in a random access channel opportunity selected from a subset of the set of random access channel opportunities associated with the one or more synchronization signal blocks, the random access channel opportunity being selected from the subset of the set of random access channel opportunities based on a duration between a last received downlink transmission and the random access channel opportunity satisfying a threshold duration.

[0007]

[0007] An apparatus for wireless communication in a UE is described. The apparatus may include a processor, a memory coupled to the processor, and instructions stored in the memory. The instructions may be executable by the processor to cause the apparatus to thereby receive a message including a plurality of mappings of respective sets of synchronization signal blocks to respective sets of random access channel opportunities. The instructions may be executable by the processor to cause the apparatus to receive one or more synchronization signal blocks of the set of synchronization signal blocks, the set of synchronization signal blocks being identified from the respective sets of synchronization signal blocks according to one mapping of a plurality of mappings determined at least in part based on a capability of the UE, the set of synchronization signal blocks being associated with a set of random access channel opportunities. The instructions may be executable by the processor to cause the apparatus to transmit a random access preamble in a random access channel opportunity selected from a subset of the set of random access channel opportunities associated with the one or more synchronization signal blocks, the random access channel opportunity being selected from the subset of the set of random access channel opportunities based on a duration between a last received downlink transmission and the random access channel opportunity satisfying a threshold duration.

[0008] Another apparatus for wireless communication in a UE is described. The apparatus may include means for receiving a message including a plurality of mappings of a respective set of synchronization signal blocks to a respective set of random access channel opportunities. The apparatus may include means for receiving one or more synchronization signal blocks of the set of synchronization signal blocks, the set of synchronization signal blocks being identified from the respective set of synchronization signal blocks according to one of a plurality of mappings determined at least in part based on a capability of the UE, the set of synchronization signal blocks being associated with a set of random access channel opportunities. The apparatus may include means for transmitting a random access preamble in a random access channel opportunity selected from a subset of the set of random access channel opportunities associated with the one or more synchronization signal blocks, the random access channel opportunity being selected from the subset of the set of random access channel opportunities based on a duration between a last received downlink transmission and the random access channel opportunity satisfying a threshold duration.

[0009]

[0009] A non-transitory computer readable medium storing code for wireless communication in a UE is described. The code may include instructions executable by a processor for receiving a message including a plurality of mappings of respective sets of synchronization signal blocks to respective sets of random access channel opportunities. The code may include instructions executable by a processor for receiving one or more synchronization signal blocks of the set of synchronization signal blocks, the set of synchronization signal blocks being identified from the respective sets of synchronization signal blocks according to one mapping of a plurality of mappings determined at least in part based on a capability of the UE, the set of synchronization signal blocks being associated with a set of random access channel opportunities. The code may include instructions executable by a processor for transmitting a random access preamble during a random access channel opportunity selected from a subset of the set of random access channel opportunities associated with the one or more synchronization signal blocks, the random access channel opportunity being selected from the subset of the set of random access channel opportunities based on a duration between a last received downlink transmission and the random access channel opportunity satisfying a threshold duration.

[0010] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may further include an operation, feature, means, or instruction for receiving an indication of an uplink bandwidth portion for the UE to transmit a random access preamble based on a capability of the UE. Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may further include an operation, feature, means, or instruction for identifying a subset of the set of random access channel opportunities from which to select a random access channel opportunity based on a duration between a last received synchronization signal block of the one or more synchronization signal blocks and each random access channel opportunity in the subset of the set of random access channel opportunities satisfying a threshold duration.

[0011]

[0011] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may further include an operation, feature, means, or instruction for identifying a subset of the set of random access channel opportunities from which to select a random access channel opportunity, further based on excluding a random access channel opportunity among the set of random access channel opportunities preceding a synchronization signal block in a slot. In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the UE may be configured to operate in a half-duplex mode based on a capability of the UE, and the last received downlink transmission includes a control channel transmission, a data channel transmission, or a reference signal transmission.

[0012]

[0012] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, receiving a message may include an operation, feature, means, or instruction for receiving in the message an indication of a subset of the set of random access channel opportunities from which to select a random access channel opportunity based on the duration between a last-received synchronization signal block of one or more synchronization signal blocks and each random access channel opportunity in the subset of the set of random access channel opportunities satisfying a threshold duration.

[0013]

[0013] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the threshold duration satisfies a minimum time for the UE to transition from a receive mode to a transmit mode. In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the UE may be configured to utilize frequency division duplexing, and the minimum time for the UE to transition from a receive mode to a transmit mode may be based on a numerology used for a random access preamble, a capability of the UE, or both. In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the UE may be configured to utilize time division duplexing, and the minimum time for the UE to transition from a receive mode to a transmit mode may be based on a numerology used for a random access preamble, a capability of the UE, a radio frequency switching time at the UE, or a combination thereof.

[0014] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the threshold duration may be equal to a duration configured in the UE for switching from a receive mode to a transmit mode in a time division duplex mode. Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may further include an operation, feature, means, or instruction for receiving an indication of the threshold duration based on a capability of the UE, and the random access channel opportunity may be selected based on receiving the indication of the threshold duration.

[0015]

[0015] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may further include an operation, feature, means, or instruction for selecting a random access channel opportunity in which to transmit a random access preamble based on a reference signal received power measurement of one synchronization signal block of the one or more synchronization signal blocks satisfying a threshold. In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the message includes a system information message or a radio resource control message. In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the capability of the UE includes a reduced capability. In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the set of synchronization signal blocks is indicated by ssb-PositionsInBurst in system information block 1 or in ServingCellConfigCommon.

[0016] A method for wireless communication in a base station is described. The method may include transmitting a message to a set of a plurality of UEs, the message including a first mapping of a set of synchronization signal blocks to a first set of random access channel opportunities for a first subset of the plurality of UEs having a first capability and a second mapping of the set of synchronization signal blocks to a second set of random access channel opportunities for a second subset of the plurality of UEs having a second capability, transmitting the set of synchronization signal blocks, and receiving, in response to transmitting the set of synchronization signal blocks, from one UE of the set of the plurality of UEs, a random access preamble on a random access channel opportunity selected from the first set of random access channel opportunities according to the first mapping based on the UEs having the first capability.

[0017]

[0017] An apparatus for wireless communication in a base station is described. The apparatus may include a processor, a memory coupled to the processor, and instructions stored in the memory. The instructions may be executable by the processor to cause the apparatus to transmit, to a set of multiple UEs, a message including a first mapping of a set of synchronization signal blocks to a first set of random access channel opportunities for a first subset of the multiple UEs having a first capability and a second mapping of the set of synchronization signal blocks to a second set of random access channel opportunities for a second subset of the multiple UEs having a second capability, transmit the set of synchronization signal blocks, and in response to transmitting the set of synchronization signal blocks, receive, from one UE of the set of multiple UEs, a random access preamble on a random access channel opportunity selected from the first set of random access channel opportunities according to the first mapping based on the UEs having the first capability.

[0018] Another apparatus for wireless communication in a base station is described. The apparatus may include means for transmitting a message to a set of a plurality of UEs, the message including a first mapping of a set of synchronization signal blocks to a first set of random access channel opportunities for a first subset of the plurality of UEs having a first capability and a second mapping of the set of synchronization signal blocks to a second set of random access channel opportunities for a second subset of the plurality of UEs having a second capability, means for transmitting the set of synchronization signal blocks, and means for receiving, in response to transmitting the set of synchronization signal blocks, from one UE of the set of the plurality of UEs, a random access preamble on a random access channel opportunity selected from the first set of random access channel opportunities according to the first mapping based on the UEs having the first capability.

[0019] A non-transitory computer-readable medium storing code for wireless communication in a base station is described. The code may include instructions executable by a processor for transmitting a message to a set of a plurality of UEs, the message including a first mapping of a set of synchronization signal blocks to a first set of random access channel opportunities for a first subset of the plurality of UEs having a first capability and a second mapping of the set of synchronization signal blocks to a second set of random access channel opportunities for a second subset of the plurality of UEs having a second capability, transmitting the set of synchronization signal blocks, and receiving, in response to transmitting the set of synchronization signal blocks, from one UE of the set of the plurality of UEs, a random access preamble on a random access channel opportunity selected from the first set of random access channel opportunities according to the first mapping based on the UE having the first capability.

[0020] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may further include an operation, feature, means, or instruction for transmitting an indication of an uplink bandwidth portion for the UE to transmit a random access preamble based on a first capability of the UE. Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may further include an operation, feature, means, or instruction for identifying a first set of random access channel opportunities from which the UE may select a random access channel opportunity based on a duration between a last-transmitted synchronization signal block of the set of synchronization signal blocks and each random access channel opportunity in the first set of random access channel opportunities satisfying a threshold duration.

[0021] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the threshold duration satisfies a minimum time for a UE to transition from a receive mode to a transmit mode. In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the UE may be configured to utilize frequency division duplexing, and the minimum time for the UE to transition from a receive mode to a transmit mode may be based on a numerology used for the random access preamble, a capability of the UE, or both.

[0022] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the UE may be configured to utilize time division duplexing, and the minimum time for the UE to transition from a receive mode to a transmit mode may be based on a numerology used for the random access preamble, a capability of the UE, a radio frequency switching time at the UE, or a combination thereof. Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may further include an operation, feature, means, or instruction for identifying a first set of random access channel opportunities from which the UE may select a random access channel opportunity, further based on excluding random access opportunities preceding a synchronization signal block in a slot.

[0023]

[0023] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the threshold duration may be equal to a duration configured in the UE for switching from a receive mode to a transmit mode in a time division duplex mode. Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may further include an operation, feature, means, or instruction for transmitting an indication of the threshold duration to the UE based on a capability of the UE, and receiving a random access preamble during the random access channel opportunity may be based on transmitting the indication of the threshold duration.

[0024] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, receiving the random access preamble may include an operation, feature, means, or instruction for receiving a random access preamble during a random access channel opportunity based on a reference signal received power measurement of a synchronization signal block in the set of synchronization signal blocks satisfying a threshold. In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the message includes a system information message or a radio resource control message. In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the first capability of the UE includes a reduced capability. [Brief description of the drawings]

[0025] [Figure 1]

[0025] FIG. 1 illustrates an example of a wireless communication system that supports random access opportunity (RO) selection for reduced capability (RedCap) user equipment (UE) according to an aspect of the present disclosure. [Diagram 2]

[0026] FIG. 1 illustrates an example of different categories of UEs, according to an aspect of the disclosure. [Diagram 3]

[0027] FIG. 1 illustrates an example of half-duplex (HD) frequency division duplexing (FDD) in accordance with aspects of the present disclosure. [Figure 4]

[0028] FIG. 1 illustrates an example of timing advance during time division duplexing (TDD) in accordance with an aspect of the present disclosure. [Diagram 5]

[0029] FIG. 1 illustrates an example of a wireless communication system supporting RO selection for RedCap UEs, according to an aspect of the present disclosure. [Figure 6]

[0030] FIG. 1 illustrates an example of a process flow for supporting RO selection for a RedCap UE, according to an aspect of the present disclosure. [Figure 7]

[0031] 1 is a block diagram of a device supporting RO selection for a RedCap UE according to an aspect of the disclosure. [Figure 8] 1 is a block diagram of a device supporting RO selection for a RedCap UE according to an aspect of the disclosure. [Figure 9]

[0032] 1 illustrates a block diagram of a communications manager supporting RO selection for a RedCap UE according to an aspect of the disclosure. [Figure 10]

[0033] FIG. 1 is a diagram of a system including a device that supports RO selection for a RedCap UE, according to an aspect of the disclosure. [Figure 11]

[0034] 1 is a block diagram of a device supporting RO selection for a RedCap UE according to an aspect of the disclosure. [Figure 12] 1 is a block diagram of a device supporting RO selection for a RedCap UE according to an aspect of the disclosure. [Figure 13]

[0035] 1 illustrates a block diagram of a communications manager supporting RO selection for a RedCap UE according to an aspect of the disclosure. [Figure 14]

[0036] FIG. 1 is a diagram of a system including a device that supports RO selection for a RedCap UE, according to an aspect of the disclosure. [Figure 15]

[0037] 1 is a flowchart illustrating a method for supporting RO selection for a RedCap UE, according to an aspect of the present disclosure. [Figure 16] 1 is a flowchart illustrating a method for supporting RO selection for a RedCap UE, according to an aspect of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0026]

[0038] In some wireless communication systems, a user equipment (UE) may use a random access procedure to establish or re-establish a connection with a base station. As part of the random access procedure, the UE may transmit a random access preamble to the base station in response to a synchronization signal block (SSB) received from the base station. The base station may transmit a set of SSBs on different beams. The UE may select an SSB from the set of SSBs, for example, if a measurement (e.g., reference signal received power (RSRP)) performed on the SSB satisfies a threshold (e.g., an RSRP threshold). Since the UE may receive each SSB on a different beam, the selection of the SSB may correspond to selecting a beam for communication with the base station. However, in some cases, a random access opportunity (RO) paired with the selected SSB may quickly follow the SSB received by the UE. Additionally or alternatively, the UE may receive another downlink transmission shortly before the RO. As a result, the random access procedure in the UE may be delayed, since the UE may not have enough time to transition to a transmit mode to transmit a random access preamble in the RO in response to the selected SSB.

[0027]

[0039] As described herein, a wireless communication system may support efficient techniques for facilitating random access procedures between a UE and a base station. In particular, a RedCap UE operating in a half-duplex mode may use the techniques described herein to efficiently select an RO in which to transmit a random access preamble based on the duration between the last received downlink transmission and the RO satisfying a threshold duration. The UE may receive system information that maps a set of SSBs to a set of ROs. The UE may then select an RO from the set of ROs in which to transmit a random access preamble such that the UE has sufficient time to transition from a receive mode to a transmit mode to transmit the random access preamble. These techniques may enable a half-duplex RedCap UE to efficiently perform a random access procedure to establish or re-establish a connection with a base station.

[0028]

[0040] Aspects of the present disclosure are first described in the context of a wireless communication system. Example processes and signaling exchanges supporting RO selection for RedCap UEs are then described. Aspects of the present disclosure are further illustrated by and described with reference to apparatus diagrams, system diagrams, and flow charts relating to RO selection for RedCap UEs.

[0029]

[0041] 1 illustrates an example of a wireless communication system 100 supporting RO selection for RedCap UEs according to an aspect of the disclosure. The wireless communication system 100 may include one or more base stations 105, one or more UEs 115, and a core network 130. In some examples, the wireless communication system 100 may be a Long Term Evolution (LTE) network, a LTE-Advanced (LTE-A) network, a LTE-A Pro network, or a New Radio (NR) network. In some examples, the wireless communication system 100 may support enhanced broadband communications, ultra-reliable (e.g., mission-critical) communications, low latency communications, communications with low-cost and low-complexity devices, or any combination thereof.

[0030]

[0042] The base stations 105 may be distributed throughout a geographic area to form the wireless communication system 100 and may be devices of different forms or with different capabilities. The base stations 105 and the UEs 115 may communicate wirelessly via one or more communication links 125. Each base station 105 may provide a coverage area 110 within which the UEs 115 and the base stations 105 may establish one or more communication links 125. The coverage area 110 may be an example of a geographic area within which the base stations 105 and the UEs 115 may support communication of signals according to one or more radio access technologies.

[0031]

[0043] The UEs 115 may be distributed throughout the coverage area 110 of the wireless communication system 100, and each UE 115 may be fixed or mobile or both at different times. The UEs 115 may be devices of different forms or with different capabilities. Some example UEs 115 are shown in FIG. 1. The UEs 115 described herein may be capable of communicating with various types of devices, such as other UEs 115, base stations 105, or network equipment (e.g., core network nodes, relay devices, integrated access and backhaul (IAB) nodes, or other network equipment) as shown in FIG. 1.

[0032]

[0044] The base stations 105 may communicate with the core network 130, or with each other, or both. For example, the base stations 105 may interface with the core network 130 through one or more backhaul links 120 (e.g., via an S1, N2, N3, or other interface). The base stations 105 may communicate with each other via the backhaul links 120 (e.g., via an X2, Xn, or other interface), either directly (e.g., between the base stations 105) or indirectly (e.g., via the core network 130), or both. In some examples, the backhaul links 120 may be or include one or more wireless links.

[0033]

[0045] One or more of the base stations 105 described herein may include or be referred to as a base transceiver station, wireless base station, access point, wireless transceiver, NodeB, eNodeB (eNB), next generation NodeB or giga-NodeB (any of which may be referred to as a gNB), Home NodeB, Home eNodeB, or other suitable terminology by one skilled in the art.

[0034]

[0046] The UE 115 may include or be referred to as a mobile device, a wireless device, a remote device, a handheld device, or a subscriber device, or any other suitable terminology, and a "device" may be referred to as a unit, a station, a terminal, or a client, among various examples. The UE 115 may also include or be referred to as a personal electronic device, such as a cellular phone, a personal digital assistant (PDA), a tablet computer, a laptop computer, or a personal computer. In some examples, the UE 115 may include or be referred to as a wireless local loop (WLL) station, an Internet of Things (IoT) device, an Internet of Everything (IoE) device, or a machine type communications (MTC) device, among various examples, which may be implemented in various items, such as an appliance, or a vehicle, a meter, among various examples.

[0035]

[0047] The UEs 115 described herein may be capable of communicating with various types of devices, such as other UEs 115, which may act as relays, as shown in FIG. 1, as well as base stations 105 and network equipment, including macro eNBs or gNBs, small cell eNBs or gNBs, or relay base stations, among various examples.

[0036]

[0048] The UE 115 and the base station 105 may wirelessly communicate with each other via one or more communication links 125 on one or more carriers. The term “carrier” may refer to a set of radio frequency spectrum resources having a defined physical layer structure for supporting the communication link 125. For example, a carrier used for the communication link 125 may include a portion (e.g., a bandwidth part (BWP)) of a radio frequency spectrum band that operates according to one or more physical layer channels for a given radio access technology (e.g., LTE, LTE-A, LTE-A Pro, NR). Each physical layer channel may carry collection signaling (e.g., synchronization signals, system information), control signaling to coordinate operation on the carrier, user data, or other signaling. The wireless communication system 100 may support communication with the UE 115 using carrier aggregation or multi-carrier operation. The UE 115 may be configured with multiple downlink component carriers and one or more uplink component carriers according to a carrier aggregation configuration. Carrier aggregation may be used with both Frequency Division Duplex (FDD) and Time Division Duplex (TDD) component carriers.

[0037]

[0049] In some examples (e.g., in a carrier aggregation configuration), a carrier may also have collection or control signaling to coordinate operation with respect to other carriers. A carrier may be associated with a frequency channel (e.g., evolved universal mobile telecommunication system terrestrial radio access (E-UTRA) absolute radio frequency channel number (EARFCN)) and may be arranged according to a channel raster for discovery by the UE 115. A carrier may operate in a standalone mode, where initial collection and connection may be made by the UE 115 over the carrier, or the carrier may operate in a non-standalone mode, where a connection is anchored using a different carrier (e.g., of the same or different radio access technology).

[0038]

[0050] The communication links 125 shown in the wireless communication system 100 may include uplink transmissions from the UE 115 to the base station 105 or downlink transmissions from the base station 105 to the UE 115. A carrier may carry downlink or uplink communications (e.g., in FDD mode) or may be configured to carry downlink and uplink communications (e.g., in TDD mode).

[0039]

[0051] A carrier may be associated with a particular bandwidth of the radio frequency spectrum, and in some examples, the carrier bandwidth may be referred to as the carrier or the "system bandwidth" of the wireless communication system 100. For example, the carrier bandwidth may be one of several determined bandwidths for a particular radio access technology carrier (e.g., 1.4, 3, 5, 10, 15, 20, 40, or 80 Megahertz (MHz)). A device of the wireless communication system 100 (e.g., a base station 105, a UE 115, or both) may have a hardware configuration that supports communication over a particular carrier bandwidth or may be configurable to support communication over one of a set of carrier bandwidths. In some examples, the wireless communication system 100 may include a base station 105 or a UE 115 that supports simultaneous communication over a carrier associated with multiple carrier bandwidths. In some examples, each served UE 115 may be configured to operate over a portion (e.g., a sub-band, BWP) or all of the carrier bandwidth.

[0040]

[0052] A signal waveform transmitted on a carrier may be composed of multiple subcarriers (e.g., using a multi-carrier modulation (MCM) technique such as orthogonal frequency division multiplexing (OFDM) or discrete Fourier transform spread OFD (DFT-S-OFDM)). In a system employing MCM techniques, a resource element may consist of one symbol period (e.g., the duration of one modulation symbol) and one subcarrier, where the symbol period and the subcarrier spacing are inversely related. The number of bits carried by each resource element may depend on the modulation scheme (e.g., the order of the modulation scheme, the coding rate of the modulation scheme, or both). Thus, the more resource elements the UE 115 receives and the higher the order of the modulation scheme, the higher the data rate may be for the UE 115. Wireless communication resources may refer to a combination of radio frequency spectrum resources, time resources, and spatial resources (e.g., spatial layers or beams), where the use of multiple spatial layers may further increase data rates or data integrity for communications with UE 115.

[0041]

[0053] The time interval for the base station 105 or the UE 115 is, for example, T s =1 / (Δf max N f ) seconds, where Δf max may represent the maximum supported subcarrier spacing, and N f may represent the maximum supported discrete Fourier transform (DFT) size. The communication resource time intervals may be organized according to radio frames, each having a specified duration (e.g., 10 milliseconds (ms)). Each radio frame may be identified by a system frame number (SFN) (e.g., ranging from 0 to 1023).

[0042]

[0054] Each frame may include multiple consecutively numbered subframes or slots, and each subframe or slot may have the same duration. In some examples, a frame may be divided (e.g., in the time domain) into subframes, and each subframe may be further divided into several slots. Alternatively, each frame may include a variable number of slots, and the number of slots may depend on the subcarrier spacing. Each slot may include several symbol periods (e.g., depending on the length of a cyclic prefix prepended to each symbol period). In some wireless communications systems 100, a slot may be further divided into multiple minislots that include one or more symbols. Excluding the cyclic prefix, each symbol period may include one or more (e.g., N f The duration of a symbol period may depend on the subcarrier spacing or the frequency band of operation.

[0043]

[0055] A subframe, slot, minislot, or symbol may be the smallest scheduling unit (e.g., in the time domain) of the wireless communications system 100 and may be referred to as a transmission time interval (TTI). In some examples, the TTI duration (e.g., the number of symbol periods in a TTI) may be variable. Additionally or alternatively, the smallest scheduling unit of the wireless communications system 100 may be dynamically selected (e.g., among a burst of shortened TTIs (sTTIs)).

[0044]

[0056] The physical channels may be multiplexed on the carriers according to various techniques. The physical control channels and the physical data channels may be multiplexed on the downlink carriers using, for example, one or more of a time division multiplexing (TDM), a frequency division multiplexing (FDM), or a hybrid TDM-FDM technique. A control region (e.g., a control resource set (CORESET)) for the physical control channels may be defined by a number of symbol periods and may extend across the system bandwidth of the carrier or a subset of the system bandwidth. One or more control regions (e.g., CORESET) may be configured for a set of UEs 115. For example, one or more of the UEs 115 may monitor or search the control region for control information according to one or more search space sets, and each search space set may include one or more control channel candidates at one or more aggregation levels configured in a cascaded manner. The aggregation level for a control channel candidate may refer to the number of control channel resources (e.g., control channel elements (CCEs)) associated with the coded information for a control information format having a given payload size. The search space sets may include a common search space set configured for sending control information to multiple UEs 115 and a UE-specific search space set for sending control information to a specific UE 115.

[0045]

[0057] In some examples, the base stations 105 may be mobile and therefore may provide communication coverage to moving geographic coverage areas 110. In some examples, the different geographic coverage areas 110 associated with different technologies may overlap, but the different geographic coverage areas 110 may be supported by the same base station 105. In other examples, overlapping geographic coverage areas 110 associated with different technologies may be supported by different base stations 105. The wireless communication system 100 may include a heterogeneous network, for example, where different types of base stations 105 provide coverage to various geographic coverage areas 110 using the same or different radio access technologies.

[0046]

[0058] Some UEs 115, such as MTC or IoT devices, may be low-cost or low-complexity devices and may provide automated communication between machines (e.g., via Machine-to-Machine (M2M) communication). M2M communication or MTC may refer to data communication technologies that allow devices to communicate with each other or with the base station 105 without human intervention. In some examples, M2M communication or MTC may include communication from devices that incorporate sensors or meters to measure or capture information and relay that information to a central server or application program that utilizes such information or presents the information to a human who interacts with the application program. Some UEs 115 may be designed to collect information or enable automated behavior of machines or other devices. Examples of applications for MTC devices include smart metering, inventory monitoring, water level monitoring, equipment monitoring, healthcare monitoring, wildlife monitoring, weather and geological event monitoring, fleet management and tracking, remote security sensing, physical access control, and transaction-based business billing.

[0047]

[0059] Some UEs 115 may be configured to employ operating modes that reduce power consumption, such as half-duplex (HD) communication (e.g., a mode that supports one-way communication via transmission or reception, but not simultaneous transmission and reception). In some examples, the half-duplex communication may be performed at a reduced peak rate. Other power saving techniques for the UEs 115 include entering a power saving deep sleep mode when not engaged in active communication, operating over a limited bandwidth (e.g., in accordance with narrowband communication), or a combination of these techniques. For example, some UEs 115 may be configured for operation using a narrowband protocol type associated with a defined portion or range (e.g., a set of subcarriers or resource blocks (RBs)) within a carrier, within a guard band of the carrier, or outside of a carrier.

[0048]

[0060] In some cases, the UE 115 may support Type A half-duplex operation (e.g., a first type of half-duplex operation), Type B half-duplex operation (e.g., a second type of half-duplex operation), or both. For Type A half-duplex, the UE 115 may be configured with a guard period between the downlink and the uplink (e.g., when the downlink switches to the uplink). For Type B half-duplex, the UE 115 may be configured with a guard period between the downlink and the uplink (e.g., when the downlink switches to the uplink) and another guard period between the uplink and the downlink (e.g., when the uplink switches to the downlink).

[0049]

[0061] The wireless communication system 100 may be configured to support ultra-reliable or low-latency communications, or various combinations thereof. For example, the wireless communication system 100 may be configured to support ultra-reliable low-latency communications (URLLC) or mission-critical communications. The UEs 115 may be designed to support ultra-reliable, low-latency, or critical functions (e.g., mission-critical functionality). Ultra-reliable communications may include private or group communications and may be supported by one or more mission-critical services, such as mission critical push-to-talk (MCPTT), mission critical video (MCVideo), or mission critical data (MCData). Support for mission-critical functions may include service prioritization, and the mission-critical services may be used for public safety or general commercial applications. The terms ultra-reliable, low-latency, mission-critical, and ultra-reliable low-latency may be used interchangeably herein.

[0050]

[0062] In some examples, the UE 115 may also be able to communicate directly with other UEs 115 via a device-to-device (D2D) communication link 135 (e.g., using a peer-to-peer (P2P) protocol or a D2D protocol). One or more UEs 115 utilizing D2D communication may be within the geographic coverage area 110 of the base station 105. Other UEs 115 in such a group may be outside the geographic coverage area 110 of the base station 105 or may not be able to receive transmissions from the base station 105 in some cases. In some examples, a group of UEs 115 communicating via D2D communication may utilize a one-to-many (1:M) system, where each UE 115 transmits to every other UE 115 in the group. In some examples, the base station 105 facilitates scheduling of resources for D2D communication. In other cases, D2D communication is performed between UEs 115 without the involvement of the base station 105.

[0051]

[0063] In some systems, the D2D communication link 135 may be an example of a communication channel between vehicles (e.g., UE 115), such as a sidelink communication channel. In some examples, the vehicles may communicate using vehicle-to-everything (V2X) communication, vehicle-to-vehicle (V2V) communication, or some combination thereof. The vehicles may signal information related to traffic conditions, signal scheduling, weather, safety, emergency situations, or any other information related to the V2X system. In some examples, the vehicles in the V2X system may communicate with roadside infrastructure, such as roadside units, or with a network via one or more network nodes (e.g., base stations 105) using vehicle-to-network (V2N) communication, or both.

[0052]

[0064] The core network 130 may provide user authentication, access authorization, tracking, Internet Protocol (IP) connectivity, and other access, routing, or mobility functions. The core network 130 may be an evolved packet core (EPC) or a fifth generation (5G) core (5G core, 5GC), which may include at least one control plane entity (e.g., a mobility management entity (MME), an access and mobility management function (AMF)) that manages access and mobility, and at least one user plane entity (e.g., a serving gateway (S-GW), a Packet Data Network (PDN) gateway (P-GW), or a user plane function (UPF)) that routes packets or interconnects to external networks. The control plane entity may manage non-access stratus (NAS) functions such as mobility, authentication, and bearer management for UEs 115 served by base stations 105 associated with the core network 130. User IP packets may be forwarded through a user plane entity, which may provide IP address allocation as well as other functions. The user plane entity may be connected to IP services 150 for one or more network operators. The IP services 150 may include access to the Internet, an intranet, an IP Multimedia Subsystem (IMS), or packet-switched streaming services.

[0053]

[0065] Some of the network devices, such as the base stations 105, may include subcomponents, such as an access network entity 140, which may be an example of an access node controller (ANC). Each access network entity 140 may communicate with the UE 115 through one or more other access network transmitting entities 145, which may be referred to as radio heads, smart radio heads, or transmission / reception points (TRPs). Each access network transmitting entity 145 may include one or more antenna panels. In some configurations, various functions of each access network entity 140 or base station 105 may be distributed across various network devices (e.g., radio heads and ANCs) or integrated into a single network device (e.g., the base station 105).

[0054]

[0066] The wireless communication system 100 may operate using one or more frequency bands, typically in the range of 300 megahertz (MHz) to 300 gigahertz (GHz). The 300 MHz to 3 GHz region is commonly known as the ultra-high frequency (UHF) region or decimeter band because the wavelengths range from approximately 1 decimeter to 1 meter in length. Although UHF waves may be blocked or redirected by buildings and environmental features, the waves may penetrate structures well enough for a macrocell to serve UEs 115 located indoors. Transmission of UHF waves may be associated with smaller antennas and shorter distances (e.g., less than 100 kilometers) compared to transmissions using lower frequencies and longer waves in the shortwave (high frequency (HF)) or very high frequency (VHF) portions of the spectrum below 300 MHz.

[0055]

[0067] The wireless communication system 100 may utilize both licensed and unlicensed radio frequency spectrum bands. For example, the wireless communication system 100 may utilize License Assisted Access (LAA), LTE-Unlicensed (LTE-U) radio access technology, or NR technology in an unlicensed band, such as the 5 GHz industrial, scientific, and medical (ISM) band. When operating in an unlicensed radio frequency spectrum band, devices such as the base station 105 and the UE 115 may utilize carrier sensing for collision detection and avoidance. In some examples, operation in an unlicensed band may be based on a carrier aggregation configuration in conjunction with a component carrier operating in a licensed band (e.g., LAA). Operation in an unlicensed spectrum may include downlink transmissions, uplink transmissions, P2P transmissions, or D2D transmissions, among other examples.

[0056]

[0068] The base station 105 or UE 115 may be equipped with multiple antennas that may be used to utilize techniques such as transmit diversity, receive diversity, multiple-input multiple-output (MIMO) communications, or beamforming. The antennas of the base station 105 or UE 115 may be located in one or more antenna arrays or antenna panels that may support MIMO operations or transmit or receive beamforming. For example, one or more base station antennas or antenna arrays may be collocated in an antenna assembly, such as an antenna tower. In some examples, the antennas or antenna arrays associated with the base station 105 may be located in various geographic locations. The base station 105 may have an antenna array with several rows and columns of antenna ports that the base station 105 may use to support beamforming of communications with the UE 115. Similarly, the UE 115 may have one or more antenna arrays that may support various MIMO or beamforming operations. Additionally or alternatively, the antenna panels may support radio frequency beamforming for signals transmitted through the antenna ports.

[0057]

[0069] Beamforming, sometimes referred to as spatial filtering, directional transmission, or directional reception, is a signal processing technique that may be used in a transmitting or receiving device (e.g., base station 105, UE 115) to shape or steer an antenna beam (e.g., transmit beam, receive beam) along a spatial path between the transmitting device and the receiving device. Beamforming may be achieved by combining signals communicated through antenna elements of an antenna array such that some signals propagating in a particular orientation relative to the antenna array are subject to constructive interference, while other signals are subject to destructive interference. Adjustment of signals communicated through antenna elements may include a transmitting or receiving device applying an amplitude offset, a phase offset, or both to signals carried through an antenna element associated with the device. The adjustment associated with each of the antenna elements may be defined by a beamforming weight set associated with a particular orientation (e.g., relative to the transmitting or receiving device's antenna array, or to some other orientation).

[0058]

[0070] In the wireless communication system 100, the UEs 115 may be classified based on the capabilities of the UEs 115. FIG. 2 illustrates an example of different categories 200 of UEs according to an aspect of the disclosure. Some UEs 115 may be classified as URLLC UEs 205 and some UEs 115 may be classified as enhanced mobile broadband (eMBB) UEs 210 (e.g., premium smartphones). The URLLC UEs 205 and eMBB UEs 210 may support communication in a 5G (e.g., premium 5G) or NR network. Some other UEs 115 may be classified as low power wide area (LPWA) massive MTC (mMTC) UEs 215. The LPWA mMTC UEs 215 may support communication in an LTE network. In addition to these UEs 115, some other UEs 115 in the wireless communication system 100 may be classified as NR-lite UEs 220.

[0059]

[0071] In some aspects, it may be appropriate to find more efficient and cost-effective ways to scale and deploy some networks (e.g., NR networks). For example, reliability requirements may be relaxed so that some networks may achieve peak throughput and minimal latency. These networks may be associated with improved efficiency (e.g., power consumption and system overhead) and lower cost. Furthermore, in some examples, these networks may support UEs 115 classified as NR-lite UEs 220, which may be associated with reduced capabilities and lower cost. NR-lite UEs 220 may be referred to as RedCap UEs 115. RedCap UEs 115 may include wearables, industrial wireless sensor networks (IWSNs), surveillance cameras, and low-end smartphones. Furthermore, the RedCap UE 115 may operate on a large frequency band (e.g., 20 MHz or up to 100 MHz), while other UEs 115, such as NB-IoT UEs and eMTC UEs 115, may operate on narrower bands (e.g., one resource block or six resource blocks).

[0060]

[0072] In some cases, the RedCap UE 115 may support communications using time division duplex (TDD) and frequency division duplex (FDD) with low spectral efficiency and scalable numerology, and full-duplex (FD) or half-duplex (HD) modes. When using FDD, the RedCap UE 115 may communicate with the base station 105 over a paired spectrum. The paired spectrum may include a first frequency band for uplink communications and a second frequency band for downlink communications. When using TDD, the RedCap UE 115 may communicate with the base station 105 over an unpaired spectrum. That is, the RedCap UE 115 may transmit on the uplink and receive on the downlink on the same carrier.

[0061]

[0073] FIG. 3 illustrates an example of a frequency division duplex (FDD) 300 at half-duplex according to an aspect of the disclosure. Since some RedCap UEs 115 may operate in half-duplex mode, these UEs 115 may achieve lower noise figure and insertion loss with lower cost and power savings. In some cases, cost savings may be achieved by replacing a duplexer in a half-duplex UE 115 with a switch. A switch may reduce cost compared to a duplexer, and the cost savings gain may scale up with multi-band support, since a UE may have multiple duplexers to support full-duplex across different bands. Additionally, power savings may be achieved by sequential toggling of the transmit phase locked loop (PLL) and the receive PLL, since the transceiver chains in the half-duplex UE 115 may be in a low power state when communication is going in the opposite direction.

[0062]

[0074] In FIG. 3, a half-duplex UE 115 may transmit on an uplink on a first carrier 305 and receive on a downlink on a second carrier 310. For example, the half-duplex UE 115 may transmit on an uplink on a first carrier 305 in a first time period 315-a, receive on a downlink on a second carrier 310 in a second time period 315-b, and transmit on an uplink on the first carrier 305 in a third time period 315-c. When transitioning from transmitting on the uplink to receiving on the downlink, the half-duplex UE 115 may lock a transmit PLL. Similarly, when transitioning from receiving on the downlink to transmitting on the uplink, the half-duplex UE 115 may lock a receive PLL. By supporting FDD in half-duplex mode, the half-duplex UE 115 may achieve lower latency and higher throughput in addition to more flexible downlink and uplink switching locations.

[0063]

[0075] In some aspects, in addition to or as an alternative to FDD, the half-duplex UE 115 may communicate with the base station 105 using TDD. In such aspects, the half-duplex UE 115 may be configured with a slot format that indicates which slots are to be used for the uplink, which slots are to be used for the downlink, and which slots are flexible. When a TDD slot includes a downlink symbol and an uplink symbol, a flexible symbol may be configured between the downlink symbol and the uplink symbol (e.g., when the downlink switches to the uplink), but there may be at least one flexible symbol between the downlink symbol and the uplink symbol (e.g., the minimum number of flexible symbols may be equal to 1). Furthermore, a flexible symbol may not be configured between the uplink symbol and the downlink symbol (e.g., when the uplink switches to the downlink).

[0064]

[0076] The UE 115 may transmit an uplink signal using a timing advance, but since the downlink signal may take some time to arrive at the UE 115, flexible symbols may be configured when the downlink switches to an uplink and not configured when the uplink switches to a downlink. FIG. 4 illustrates an example of a timing advance 400 during TDD according to an aspect of the disclosure. The UE 115 may transmit an uplink frame 410 to the base station prior to the downlink frame 405 such that the uplink frame 410 aligns with the downlink frame 405 at the base station 105. In some cases, the UE 115 may calculate a timing advance for an uplink transmission to the base station 105 based on one or more values. In some examples, the base station 10 ... TA to the UE 115, but TA,offset The value of can vary. Furthermore, T cmay refer to the basic unit of time in a wireless communication system. The UE 115 may then use these values ​​to calculate a timing advance for uplink transmissions to the base station 105.

[0065]

[0077] Tables 1, 2, and 3 below show the peak data rates in different duplexing modes. For a RedCap UE 115 with one transmitter and one receiver (1T1R), the RedCap UE 115 may use a maximum modulation order of 64 quadrature amplitude modulation (QAM) and a maximum code rate of 948 / 1024, and the RedCap UE 115 may achieve a downlink overhead of 0.14 and an uplink overhead of 0.08. In NR TDD, the RedCap UE 115 may be configured with a DDSU slot format, where "D" corresponds to a downlink symbol, "S" corresponds to a special symbol, and "U" corresponds to an uplink symbol (e.g., format 28 has one "S" symbol and n f In HD-FDD for NR Type-A, the RedCap UE 115 may be configured with a switching gap between the downlink and the uplink (e.g., when the downlink switches to the uplink), and the switching gap may be based on the subcarrier spacing (SCS). g For a 15 kHz SCS with n = 1, the RedCap UE 115 may experience no loss for format 28, but g For a 30 kHz SCS with n = 2, the RedCap UE 115 may experience a 3% loss for format 28. The RedCap UE 115 also includes some guard symbols, n g Format 28 where n = 1, or g DDSU slot format, such as format 29, where .times. ...

[0066] [Table 1]

[0067] [Table 2]

[0068] [Table 3]

[0069]

[0078] In the wireless communication system 100, the UE 115 may use a random access procedure to establish or re-establish a connection with the base station 105. As part of the random access procedure, the UE 115 may transmit a random access preamble to the base station 105 in response to an SSB received from the base station 105. The base station 105 may transmit a set of SSBs associated with different beams. The UE 115 may select an SSB from the set of SSBs, for example, if a measurement (e.g., RSRP) performed on the SSB satisfies a threshold (e.g., RSRP threshold). Since the UE 115 may receive each SSB on a different beam, the selection of the SSB may correspond to selecting a beam for communication with the base station 105. However, in some cases, the RO paired with the selected SSB may quickly follow the SSB received by the UE 115. Additionally or alternatively, the UE 115 may receive another downlink transmission shortly before the RO. As a result, the random access procedure at the UE 115 may be delayed because the UE 115 may not have enough time to transition to a transmit mode to transmit a random access preamble in the RO in response to the selected SSB. The wireless communication system 100 may support efficient techniques for facilitating a random access procedure between the UE 115 and the base station 105.

[0070]

[0079] FIG. 5 illustrates an example of a wireless communication system 500 supporting RO selection for RedCap UEs according to aspects of the disclosure. The wireless communication system 500 includes a UE 115-a, which may be an example of a UE 115 described with reference to FIG. 1. For example, the UE 115-a may be an example of a RedCap UE 115 described with reference to FIG. 1-5. The wireless communication system 500 also includes a base station 105-a, which may be an example of a base station 105 described with reference to FIG. 1. The UE 115-a may communicate with the base station 105-a over resources of a carrier 505 and a carrier 510 (e.g., which may correspond to different carriers or the same carrier). The wireless communication system 500 may implement aspects of the wireless communication system 100. For example, the wireless communication system 500 may support efficient techniques for facilitating random access procedures between the UE 115-a and the base station 105-a.

[0071]

[0080] In the example of FIG. 5, the base station 105-a may transmit system information or radio resource control (RRC) signaling to the UE 115-a indicating a configuration for communicating with the UE 115-a. The UE 115-a may then decode the system information or RRC signaling and obtain an uplink bandwidth portion (BWP) for transmission to the base station 105-a and a random-access channel (RACH) configuration for the UE 115-a. The RACH configuration may include physical RACH (PRACH) resources, a mapping pattern, parameters for RO validation, one or more RO selection rules, and power control parameters. The mapping pattern may be referred to as an SSB-to-PRACH mapping pattern, or SSB-to-RO mapping, and may map a set of SSBs to one or more sets of ROs in which the UE 115-a may transmit a random access preamble.

[0072]

[0081] The base station 105-a may indicate an SSB-to-PRACH mapping pattern separately for the RedCap UE 115 (e.g., UE 115-a) and the non-RedCap UE 115. For example, the base station 105-a may include different parameters in the system information (e.g., ssb-perRACH-OccasionAndCB-PreamblesPerSSB, ra-ssb-OccasionMaskIndex, etc.) for the RedCap UE 115 and the non-RedCap UE 115. Alternatively, the base station 105-b may indicate a common SSB-to-RO mapping pattern for the RedCap UE 115 and the non-RedCap UE 115. In some cases, by configuration, the base station 105-a may ensure that the PRACH resources allocated for RedCap UEs 115 (e.g., half-duplex and full-duplex RedCap UEs) can be mapped to all SSBs indicated in the system information (e.g., by ssb-PositionsInBurst in system information block one (SIB1) or in ServingCellConfigCommon) within the SSB-to-RO association pattern period (e.g., assuming that the RedCap UEs 115 are not capable of full-duplex operation). Furthermore, in some cases, the SSB-to-RO association pattern periods for the RedCap UEs 115 and non-RedCap UEs may be configured by the base station 105-a (e.g., network) to be the same or different.

[0073]

[0082] After the UE 115-a identifies an individual SSB-to-RO mapping (e.g., an SSB-to-RO mapping for the RedCap UE 115), it may be appropriate for the UE 115-a to verify the RO in the SSB-to-RO mapping (e.g., depending on the duplexing mode, the parameters for RO verification, and the UE's capabilities). Alternatively, the base station 105-a may verify the RO in the SSB-to-RO mapping before transmitting the SSB-to-RO mapping to the UE 115-a, and the UE 115-a may assume that all allocated ROs are valid. In either case, it may be appropriate for the valid RO of the RedCap UE 115 to satisfy some conditions. For example, a valid RO may not precede an SSB (e.g., a synchronization signal or a physical broadcast channel (PBCH) block) in a slot (e.g., a PRACH slot). Furthermore, a valid RO may start at least a threshold duration after the last symbol in which an SSB is received (e.g., the last SSB received symbol).

[0074]

[0083] In FIG. 5, the base station 105-a may transmit an SSB 515 to the UE 115-a, and an RO 520 may be valid for transmitting a random access preamble (e.g., a PRACH preamble) if the RO 520 follows the SSB 515 by a threshold duration. That is, the RO 520 may be valid if the gap 525 between the SSB 515 and the RO 520 is equal to or greater than the threshold duration. The threshold duration may be N gap,RC If UE 115-a is performing a RACH procedure using FDD (e.g., on a paired spectrum), N gap,RC may depend on the numerology of the PRACH preamble and the UE capabilities (e.g., the capabilities of the UE 115-a). If the UE 115-a is performing the RACH procedure using TDD (e.g., over an unpaired spectrum), N gap,RCmay depend on the numerology of the PRACH preamble, the UE capabilities (e.g., the capabilities of the UE 115-a), and the radio frequency switching time at the UE 115-a (e.g., when the center frequencies of the downlink and uplink BWP pairs are not aligned).

[0075]

[0084] In one aspect, the threshold duration may be greater than the minimum receive-to-transmit (RX-to-TX) switching time for half-duplex FDD. symbol N gap,RC may be greater than the minimum RX-to-TX switching time (e.g., in TDD), and T symbol represents the duration of a symbol and is based on the reference SCS of the PRACH slot. In this aspect, the base station 105-a transmits N gap,RC (e.g., N gap,RC may be specified by a look-up table (LUT) or may be signaled in system information (e.g., SIB1), or both. In another aspect, the threshold duration may be equal to the duration configured in the UE 115-a for RX-to-TX switching (e.g., N gap,RC =N gap Or N flexible ).

[0076]

[0085] When the RO in the SSB-to-RO mapping is verified, the UE 115-a may select an RO 520 in which to transmit a RACH preamble to the base station 105-a in response to the SSB 515. That is, the UE 115-a may select an RO 520 from the valid ROs. Furthermore, the UE 115-a may perform RO selection according to a synchronization signal (SS) RSRP (SS-RSRP) measurement and the power class and antenna efficiency of the UE 115-a. The UE 115-a may also perform priority or collision handling for PRACH transmission (e.g., with RO reselection or cancellation if a collision occurs). After selecting the RO 520, the UE 115-a may transmit a RACH preamble to the base station 105-a on the RO 520 (e.g., a power-controlled PRACH transmission during an uplink BWP allocated to the UE 115-a). In some cases, half-duplex and full-duplex RedCap UEs 115 may follow the same or different rules in selecting an RO from the valid ROs in which to transmit the RACH preamble (eg, for directional collision handling).

[0077]

[0086] In one aspect, the half-duplex and full-duplex RedCap UEs 115 may follow different rules when selecting an RO 520. In this aspect, the half-duplex RedCap UE 115 may select an RO 520 if the RO is at least N gap,RCsymbols, the half-duplex RedCap UE 115 may transmit a RACH preamble on a valid RO after the last downlink symbol (e.g., including PDCCH, PDSCH, channel state information reference signal (CSI-RS), tracking reference signal (TRS), or positioning reference signal (PRS)). Furthermore, the half-duplex RedCap UE 115 may transmit a RACH preamble on a valid RO if the reference signal received power (RSRP) of the SSB preceding the RO is above a threshold (γ1) preconfigured by the base station 105-a (e.g., network), where the threshold (γ1) is a function of the power class, antenna efficiency, and other capabilities of the UE 115-a. Alternatively, the full-duplex UE 115 may transmit a RACH preamble on a valid RO if the RSRP of the SSB preceding the RO exceeds a threshold (γ2) preconfigured by the base station 105-a (e.g., a network), where the threshold (γ2) is a function of the power class, antenna efficiency, and other capabilities of the UE 115-a.

[0078]

[0087] In another aspect, the half-duplex and full-duplex RedCap UEs 115 may follow the same rules in selecting the RO 520. In this aspect, the half-duplex or full-duplex RedCap UEs 115 may follow the same rules in selecting the RO 520 if the RO is at least N gap,RCsymbols, the UE 115 may transmit a RACH preamble on a valid RO after the last downlink symbol (e.g., including a PDCCH, PDSCH, Channel State Information Reference Signal (CSI-RS), Tracking Reference Signal (TRS), or Positioning Reference Signal (PRS)). Furthermore, a half-duplex or full-duplex RedCap UE 115 may transmit a RACH preamble on a valid RO if the RSRP of the SSB preceding the RO is above a threshold (γ1) preconfigured by the base station 105-a (e.g., a network), where the threshold (γ1) is a function of the power class, antenna efficiency, and other capabilities of the UE 115-a.

[0079]

[0088] FIG. 6 illustrates an example of a process flow 600 supporting RO selection for a RedCap UE, according to an aspect of the disclosure. The process flow 600 includes a UE 115-b, which may be an example of a UE 115 described with reference to FIGS. 1-5. For example, the UE 115-b may be an example of a RedCap UE 115 described with reference to FIGS. 1-5. The process flow 600 also includes a base station 105-b, which may be an example of a base station 105 described with reference to FIGS. 1-5. The process flow 600 may implement an aspect of the wireless communication system 500. For example, the process flow 600 may support an efficient technique for facilitating a random access procedure between the UE 115-b and the base station 105-b.

[0080]

[0089] In the following description of process flow 600, signaling exchanged between the UE 115-b and the base station 105-b may be transmitted in an order different from the exemplary order shown, or operations performed by the UE 115-b and the base station 105-b may be performed in a different order or at different times. Some operations may also be omitted from process flow 600, and other operations may be added to process flow 600.

[0081]

[0090] At 605, the base station 105-b may transmit, and the UE 115-b may receive, system information indicating a first mapping of the set of SSBs to a first set of ROs (e.g., SSB-to-RO mapping for RedCap UEs) and a second mapping of the set of SSBs to a second set of ROs (e.g., SSB-to-RO mapping for other UEs). The UE 115-b may then identify the first mapping of the set of SSBs to the first set of ROs (e.g., a separate mapping directed to the UE 115-b) based on the capabilities of the UE 115-b. For example, the system information may include a header identifying the SSB-to-RO mapping for the RedCap UEs, and the UE 115-b may decode the header and identify the SSB-to-RO mapping for the RedCap UEs. Alternatively, the UE 115-b may identify the SSB-to-RO mapping for the RedCap UEs based on the location of the mapping in the system information. At 610, the base station 105-b may transmit a set of SSBs, and the UE 115-b may receive one or more SSBs of the set of SSBs.

[0082]

[0091] In some cases, at 615, the UE 115-b may identify a subset of the set of ROs from which to select an RO based on the duration between a last received SSB of the one or more SSBs and each RO in the subset of the set of ROs meeting a threshold duration. Furthermore, the UE 115-b may identify a subset of the set of ROs from which to select an RO based on excluding an RO in the set of ROs that precedes the SSB in the slot. That is, the UE 115-b may validate the subset of the set of ROs. In other cases, the base station 105-b may identify a subset of the set of ROs from which the UE 115-b may select an RO based on the duration between a last transmitted SSB of the set of SSBs and each RO in the first set of ROs meeting a threshold duration. That is, the base station 105-b may validate the RO. The base station 105-b may then send in the system information an indication of a subset of the set of ROs from which to select an RO, and the UE 115-b may receive the indication (e.g., SSB-to-RO mapping may map a set of SSBs to valid ROs).

[0083]

[0092] At 620, the UE 115-b may select an RO in which to transmit the random access preamble based on the RSRP of the SSB of the one or more SSBs satisfying a threshold. The UE 115-b may also select an RO based on the duration between the last received downlink transmission and the RO satisfying a threshold duration. In some cases, the UE 115-b may be configured to operate in a half-duplex mode, and the last received downlink transmission may include a control channel transmission, a data channel transmission, or a reference signal transmission. At 625, the UE 115-b may then transmit, and the base station 105-b may receive, the random access preamble in an RO selected from a subset of the set of ROs associated with the one or more SSBs (i.e., the RO selected at 620).

[0084]

[0093] In some cases, the base station 105-b may transmit, and the UE 115-b may receive, an indication of the threshold duration based on the capabilities of the UE 115-b. In one aspect, the threshold duration may be equal to a duration configured in the UE 115-b to switch from a receive mode to a transmit mode in a TDD mode. In another aspect, the threshold duration may satisfy a minimum time for the UE 115-b to transition from a receive mode to a transmit mode. If the UE 115-b is configured to use FDD, the minimum time for the UE 115-b to transition from a receive mode to a transmit mode may be based on a numerology used for a random access preamble, the capabilities of the UE 115-b, or both. If the UE 115-b is configured to use TDD, the minimum time for the UE 115-b to transition from a receive mode to a transmit mode may be based on a numerology used for a random access preamble, the capabilities of the UE 115-b, a radio frequency switching time in the UE 115-b, or a combination thereof.

[0085]

[0094] 7 illustrates a block diagram 700 of a device 705 supporting RO selection for a RedCap UE according to an aspect of the disclosure. The device 705 may be an example of an aspect of a UE 115 described herein. The device 705 may include a receiver 710, a transmitter 715, and a communications manager 720. The device 705 may also include a processor. Each of these components may be in communication with each other (e.g., via one or more buses).

[0086]

[0095] The receiver 710 may provide a means for receiving information, such as packets, user data, control information, or any combination thereof, associated with various information channels (e.g., control channels, data channels, information channels related to RO selection for RedCap UEs). The information may be passed to other components of the device 705. The receiver 710 may utilize a single antenna or a set of multiple antennas.

[0087]

[0096] The transmitter 715 may provide a means for transmitting signals generated by other components of the device 705. For example, the transmitter 715 may transmit information such as packets associated with various information channels (e.g., a control channel, a data channel, an information channel related to RO selection for RedCap UEs), user data, control information, or any combination thereof. In some examples, the transmitter 715 may be collocated with the receiver 710 in a transceiver module. The transmitter 715 may use a single antenna or a set of multiple antennas.

[0088]

[0097] The communications manager 720, the receiver 710, the transmitter 715, or various combinations or components thereof may be examples of means for performing various aspects of RO selection for a RedCap UE described herein. For example, the communications manager 720, the receiver 710, the transmitter 715, or various combinations or components thereof may support a method for performing one or more of the functions described herein.

[0089]

[0098] In some examples, the communications manager 720, the receiver 710, the transmitter 715, or various combinations or components thereof may be implemented in hardware (e.g., in a communications management circuit). The hardware may include a processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof configured as or otherwise supporting a means for performing the functions described in this disclosure. In some examples, the processor and a memory coupled to the processor may be configured to perform one or more of the functions described herein (e.g., by the processor executing instructions stored in the memory).

[0090]

[0099] Additionally or alternatively, in some examples, the communications manager 720, the receiver 710, the transmitter 715, or various combinations or components thereof may be implemented in code executed by a processor (e.g., as communications management software or firmware). If implemented in code executed by a processor, the functions of the communications manager 720, the receiver 710, the transmitter 715, or various combinations or components thereof may be performed by a general purpose processor, a DSP, a central processing unit (CPU), an ASIC, an FPGA, or any combination of these or other programmable logic devices (e.g., configured as or otherwise supporting a means for performing the functions described in this disclosure).

[0091]

[0100] In some examples, the communications manager 720 may be configured to perform various operations (e.g., receiving, monitoring, transmitting) using, or possibly cooperating with, the receiver 710, the transmitter 715, or both. For example, the communications manager 720 may receive information from the receiver 710 and transmit information to the transmitter 715, or may be integrated with the receiver 710, the transmitter 715, or both to receive information, transmit information, or perform various other operations described herein.

[0092]

[0101] The communications manager 720 may support wireless communications in the UE according to examples disclosed herein. For example, the communications manager 720 may be configured as or otherwise support a means for receiving a message including a plurality of mappings of respective sets of synchronization signal blocks to respective sets of random access channel opportunities. The communications manager 720 may be configured as or otherwise support a means for receiving one or more synchronization signal blocks of the set of synchronization signal blocks, the set of synchronization signal blocks being identified from the respective sets of synchronization signal blocks according to one of a plurality of mappings determined based on the capabilities of the UE, the set of synchronization signal blocks being associated with a set of random access channel opportunities. The communications manager 720 may be configured as or otherwise support a means for transmitting a random access preamble in a random access channel opportunity selected from a subset of the set of random access channel opportunities associated with the one or more synchronization signal blocks, the random access channel opportunity being selected from the subset of the set of random access channel opportunities based on the duration between a last received downlink transmission and the random access channel opportunity satisfying a threshold duration.

[0093]

[0102] By including or configuring the communications manager 720 according to examples described herein, the device 705 (e.g., a processor controlling or otherwise coupled to the receiver 710, the transmitter 715, the communications manager 720, or a combination thereof) may support techniques for reduced processing, reduced power consumption, and more efficient utilization of communications resources. In particular, because the half-duplex RedCap UE 115 can efficiently select an RO in which to transmit a RACH preamble, the half-duplex RedCap UE 115 can complete the random access procedure sooner, resulting in power savings and fewer wasted resources.

[0094]

[0103] 8 illustrates a block diagram 800 of a device 805 supporting RO selection for a RedCap UE according to an aspect of the disclosure. The device 805 may be an example of an aspect of the device 705 or UE 115 described herein. The device 805 may include a receiver 810, a transmitter 815, and a communications manager 820. The device 805 may also include a processor. Each of these components may be in communication with each other (e.g., via one or more buses).

[0095]

[0104] The receiver 810 may provide a means for receiving information, such as packets, user data, control information, or any combination thereof, associated with various information channels (e.g., control channels, data channels, information channels related to RO selection for RedCap UEs). The information may be passed to other components of the device 805. The receiver 810 may utilize a single antenna or a set of multiple antennas.

[0096]

[0105] The transmitter 815 may provide a means for transmitting signals generated by other components of the device 805. For example, the transmitter 815 may transmit information such as packets associated with various information channels (e.g., a control channel, a data channel, an information channel related to RO selection for RedCap UEs), user data, control information, or any combination thereof. In some examples, the transmitter 815 may be collocated with the receiver 810 in a transceiver module. The transmitter 815 may use a single antenna or a set of multiple antennas.

[0097]

[0106] The device 805 or various components thereof may be an example of a means for performing various aspects of RO selection for RedCap UEs described herein. For example, the communications manager 820 may include an RO configuration manager 825, an SSB manager 830, a random access preamble manager 835, or any combination thereof. The communications manager 820 may be an example of an aspect of the communications manager 720 described herein. In some examples, the communications manager 820, or various components thereof, may be configured to perform various operations (e.g., receiving, monitoring, transmitting) using or possibly cooperating with the receiver 810, the transmitter 815, or both. For example, the communications manager 820 may receive information from the receiver 810 and transmit information to the transmitter 815, or may be integrated with the receiver 810, the transmitter 815, or both to receive information, transmit information, or perform various other operations described herein.

[0098]

[0107] The communications manager 820 may support wireless communications in the UE according to examples disclosed herein. The RO configuration manager 825 may be configured as or otherwise support a means for receiving a message including a plurality of mappings of respective sets of synchronization signal blocks to respective sets of random access channel opportunities. The SSB manager 830 may be configured as or otherwise support a means for receiving one or more synchronization signal blocks of the set of synchronization signal blocks, the set of synchronization signal blocks being identified from the respective sets of synchronization signal blocks according to one of a plurality of mappings determined based on the capabilities of the UE, the set of synchronization signal blocks being associated with a set of random access channel opportunities. The random access preamble manager 835 may be configured as or otherwise support a means for transmitting a random access preamble in a random access channel opportunity selected from a subset of the set of random access channel opportunities associated with the one or more synchronization signal blocks, the random access channel opportunity being selected from the subset of the set of random access channel opportunities based on the duration between a last received downlink transmission and the random access channel opportunity satisfying a threshold duration.

[0099]

[0108] FIG. 9 illustrates a block diagram 900 of a communications manager 920 supporting RO selection for RedCap UEs according to aspects of the disclosure. Communications manager 920 may be an example of aspects of communications manager 720, communications manager 820, or both described herein. Communications manager 920, or various components thereof, may be an example of a means for performing various aspects of RO selection for RedCap UEs described herein. For example, communications manager 920 may include an RO configuration manager 925, an SSB manager 930, a random access preamble manager 935, an SSB-to-RO mapper 940, an RO validator 945, an RO timing manager 950, an RO selector 955, or any combination thereof. Each of these components may communicate directly or indirectly with each other (e.g., via one or more buses).

[0100]

[0109] The communications manager 920 may support wireless communications in the UE according to examples disclosed herein. The RO configuration manager 925 may be configured as or otherwise support a means for receiving a message including a plurality of mappings of respective sets of synchronization signal blocks to respective sets of random access channel opportunities. The SSB manager 930 may be configured as or otherwise support a means for receiving one or more synchronization signal blocks of the set of synchronization signal blocks, the set of synchronization signal blocks being identified from the respective sets of synchronization signal blocks according to one of a plurality of mappings determined based on the capabilities of the UE, the set of synchronization signal blocks being associated with a set of random access channel opportunities. The random access preamble manager 935 may be configured as or otherwise support a means for transmitting a random access preamble in a random access channel opportunity selected from a subset of the set of random access channel opportunities associated with the one or more synchronization signal blocks, the random access channel opportunity being selected from the subset of the set of random access channel opportunities based on the duration between a last received downlink transmission and the random access channel opportunity satisfying a threshold duration.

[0101]

[0110] In some examples, the RO configuration manager 925 may receive an indication of an uplink bandwidth portion for the UE to transmit a random access preamble based on the capabilities of the UE. In some examples, the RO validator 945 may be configured as or otherwise support a means for identifying a subset of a set of random access channel opportunities from which to select a random access channel opportunity based on a duration between a last-received synchronization signal block of the one or more synchronization signal blocks and each random access channel opportunity in the subset of the set of random access channel opportunities satisfying a threshold duration.

[0102]

[0111] In some examples, identifying a subset of the set of random access channel opportunities from which to select a random access channel opportunity is further based on excluding a random access channel opportunity of the set of random access channel opportunities that precedes a synchronization signal block in the slot.

[0103]

[0112] In some examples, the UE is configured to operate in a half-duplex mode based on the capabilities of the UE. In some examples, the last received downlink transmission includes a control channel transmission, a data channel transmission, or a reference signal transmission.

[0104]

[0113] In some examples, to support receiving the message, the RO configuration manager 925 may be configured as or otherwise support a means for receiving in the message an indication of a subset of the set of random access channel opportunities from which to select a random access channel opportunity based on the duration between a last-received synchronization signal block of the one or more synchronization signal blocks and each random access channel opportunity in the subset of the set of random access channel opportunities satisfying a threshold duration.

[0105]

[0114] In some examples, the threshold duration meets a minimum time for a UE to transition from a receive mode to a transmit mode.

[0106]

[0115] In some examples, the UE is configured to utilize frequency division duplexing, and the minimum time for the UE to transition from a receive mode to a transmit mode is based on the numerology used for the random access preamble, the capabilities of the UE, or both.

[0107]

[0116] In some examples, the UE is configured to utilize time division duplexing, and the minimum time for the UE to transition from a receive mode to a transmit mode is based on the numerology used for the random access preamble, the capabilities of the UE, a radio frequency switching time at the UE, or a combination thereof.

[0108]

[0117] In some examples, the threshold duration is equal to a duration configured in the UE for switching from a receive mode to a transmit mode in a time division duplex mode.

[0109]

[0118] In some examples, the RO timing manager 950 may be configured with or otherwise support a means for receiving an indication of the threshold duration based on the capabilities of the UE, and the random access channel opportunity is selected based on receiving the indication of the threshold duration.

[0110]

[0119] In some examples, the RO selector 955 may be configured as or otherwise support a means for selecting a random access channel opportunity in which to transmit a random access preamble based on a reference signal received power measurement of one synchronization signal block of one or more synchronization signal blocks satisfying a threshold.

[0111]

[0120] In some examples, the message includes a system information message or a radio resource control message. In some examples, the capabilities of the UE include reduced capabilities. In some examples, the set of synchronization signal blocks is indicated by ssb-PositionsInBurst in system information block 1 or in ServingCellConfigCommon.

[0112]

[0121] FIG. 10 illustrates a diagram of a system 1000 including a device 1005 supporting RO selection for RedCap UEs, according to aspects of the disclosure. The device 1005 may be an example of or may include components of a device 705, a device 805, or a UE 115 as described herein. The device 1005 may wirelessly communicate with one or more base stations 105, UEs 115, or any combination thereof. The device 1005 may include components for two-way voice and data communication, including components for transmitting and receiving communications, such as a communications manager 1020, an input / output (I / O) controller 1010, a transceiver 1015, an antenna 1025, a memory 1030, code 1035, and a processor 1040. These components may be in electronic communication or may be coupled (e.g., operatively, communicatively, functionally, electronically, electrically) via one or more buses (e.g., bus 1045).

[0113]

[0122] The I / O controller 1010 may manage input and output signals for the device 1005. The I / O controller 1010 may also manage peripheral devices that are not integrated with the device 1005. In some cases, the I / O controller 1010 may represent a physical connection or port to an external peripheral device. In some cases, the I / O controller 1010 may utilize an operating system such as iOS®, ANDROID®, MS-DOS®, MS-WINDOWS®, OS / 2®, UNIX®, LINUX®, or another known operating system. Additionally or alternatively, the I / O controller 1010 may represent or interact with a modem, keyboard, mouse, touch screen, or similar device. In some cases, the I / O controller 1010 may be implemented as part of a processor, such as the processor 1040. In some cases, a user may interact with the device 1005 through the I / O controller 1010 or through a hardware component controlled by the I / O controller 1010.

[0114]

[0123] In some cases, the device 1005 may include a single antenna 1025. However, in some other cases, the device 1005 may have two or more antennas 1025, which may be capable of simultaneously transmitting or receiving multiple wireless transmissions. The transceiver 1015 may communicate bidirectionally via one or more antennas 1025, a wired link, or a wireless link, as described herein. For example, the transceiver 1015 may represent a wireless transceiver and may communicate bidirectionally with another wireless transceiver. The transceiver 1015 may also include a modem for modulating packets and providing the modulated packets to the one or more antennas 1025 for transmission, and for demodulating packets received from the one or more antennas 1025. The transceiver 1015, or the transceiver 1015 and one or more antennas 1025, may be an example of the transmitter 715, transmitter 815, receiver 710, receiver 810, or any combination or components thereof, as described herein.

[0115]

[0124] The memory 1030 may include random access memory (RAM) and read only memory (ROM). The memory 1030 may store computer readable computer executable code 1035 including instructions that, when executed by the processor 1040, cause the device 1005 to perform various functions described herein. The code 1035 may be stored in a non-transitory computer readable medium, such as a system memory or another type of memory. In some cases, the code 1035 may not be directly executable by the processor 1040, but may (e.g., when compiled and executed) cause a computer to perform functions described herein. In some cases, the memory 1030 may include a basic I / O system (BIOS), which may control basic hardware or software operations, such as interactions with peripheral components or devices, among others.

[0116]

[0125] The processor 1040 may include an intelligent hardware device (e.g., a general-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, an FPGA, a programmable logic device, a discrete gate or transistor logic component, a discrete hardware component, or any combination thereof). In some cases, the processor 1040 may be configured to operate a memory array using a memory controller. In some other cases, the memory controller may be integrated with the processor 1040. The processor 1040 may be configured to execute computer-readable instructions stored in a memory (e.g., memory 1030) to cause the device 1005 to perform various functions (e.g., functions or tasks supporting RO selection for RedCap UE). For example, the device 1005 or a component of the device 1005 may include a processor 1040 and a memory 1030 coupled to the processor 1040, where the processor 1040 and the memory 1030 are configured to perform various functions described herein.

[0117]

[0126] The communications manager 1020 may support wireless communications in the UE according to examples disclosed herein. For example, the communications manager 1020 may be configured as or otherwise support a means for receiving a message including a plurality of mappings of respective sets of synchronization signal blocks to respective sets of random access channel opportunities. The communications manager 1020 may be configured as or otherwise support a means for receiving one or more synchronization signal blocks of the set of synchronization signal blocks, the set of synchronization signal blocks being identified from the respective sets of synchronization signal blocks according to one of a plurality of mappings determined at least in part based on the capabilities of the UE, the set of synchronization signal blocks being associated with a set of random access channel opportunities. The communications manager 1020 may be configured as or otherwise support a means for transmitting a random access preamble in a random access channel opportunity selected from a subset of the set of random access channel opportunities associated with the one or more synchronization signal blocks, the random access channel opportunity being selected from the subset of the set of random access channel opportunities based on a duration between a last received downlink transmission and the random access channel opportunity satisfying a threshold duration.

[0118]

[0127] By including or configuring the communications manager 1020 according to examples as described herein, the device 1005 may support techniques for reduced processing, reduced power consumption, and more efficient utilization of communications resources. In particular, because the half-duplex RedCap UE 115 can efficiently select an RO in which to transmit a RACH preamble, the half-duplex RedCap UE 115 can complete the random access procedure faster, resulting in power savings and fewer wasted resources.

[0119]

[0128] In some examples, the communications manager 1020 may be configured to perform various operations (e.g., receiving, monitoring, transmitting) using or otherwise cooperating with the transceiver 1015, one or more antennas 1025, or a combination thereof. Although the communications manager 1020 is shown as a separate component, in some examples, one or more functions described with respect to the communications manager 1020 may be supported or performed by the processor 1040, the memory 1030, the code 1035, or a combination thereof. For example, the code 1035 may include instructions executable by the processor 1040 that cause the device 1005 to perform various aspects of RO selection for RedCap UEs described herein, or the processor 1040 and the memory 1030 may be configured to perform or support such operations, as the case may be.

[0120]

[0129] 11 illustrates a block diagram 1100 of a device 1105 supporting RO selection for RedCap UEs according to an aspect of the disclosure. The device 1105 may be an example of an aspect of a base station 105 as described herein. The device 1105 may include a receiver 1110, a transmitter 1115, and a communications manager 1120. The device 1105 may also include a processor. Each of these components may be in communication with each other (e.g., via one or more buses).

[0121]

[0130] The receiver 1110 may provide a means for receiving information, such as packets, user data, control information, or any combination thereof, associated with various information channels (e.g., control channels, data channels, information channels related to RO selection for RedCap UEs). The information may be passed to other components of the device 1105. The receiver 1110 may utilize a single antenna or a set of multiple antennas.

[0122]

[0131] The transmitter 1115 may provide a means for transmitting signals generated by other components of the device 1105. For example, the transmitter 1115 may transmit information such as packets associated with various information channels (e.g., a control channel, a data channel, an information channel related to RO selection for RedCap UEs), user data, control information, or any combination thereof. In some examples, the transmitter 1115 may be collocated with the receiver 1110 in a transceiver module. The transmitter 1115 may use a single antenna or a set of multiple antennas.

[0123]

[0132] The communications manager 1120, the receiver 1110, the transmitter 1115, or various combinations or components thereof may be examples of means for performing various aspects of RO selection for RedCap UEs described herein. For example, the communications manager 1120, the receiver 1110, the transmitter 1115, or various combinations or components thereof may support a method for performing one or more of the functions described herein.

[0124]

[0133] In some examples, the communications manager 1120, the receiver 1110, the transmitter 1115, or various combinations or components thereof may be implemented in hardware (e.g., in a communications management circuit). The hardware may include a processor, a DSP, an ASIC, an FPGA or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof configured as or otherwise supporting a means for performing the functions described in this disclosure. In some examples, the processor and a memory coupled to the processor may be configured to perform one or more of the functions described herein (e.g., by the processor executing instructions stored in the memory).

[0125]

[0134] Additionally or alternatively, in some examples, the communications manager 1120, the receiver 1110, the transmitter 1115, or various combinations or components thereof may be implemented in code executed by a processor (e.g., as communications management software or firmware). If implemented in code executed by a processor, the functions of the communications manager 1120, the receiver 1110, the transmitter 1115, or various combinations or components thereof may be performed by a general purpose processor, a DSP, a CPU, an ASIC, an FPGA, or any combination of these or other programmable logic devices (e.g., configured as or otherwise supporting a means for performing the functions described in this disclosure).

[0126]

[0135] In some examples, the communications manager 1120 may be configured to perform various operations (e.g., receiving, monitoring, transmitting) using, or possibly cooperating with, the receiver 1110, the transmitter 1115, or both. For example, the communications manager 1120 may receive information from the receiver 1110 and transmit information to the transmitter 1115, or may be integrated with the receiver 1110, the transmitter 1115, or both to receive information, transmit information, or perform various other operations described herein.

[0127]

[0136] The communications manager 1120 may support wireless communications at a base station according to examples disclosed herein. For example, the communications manager 1120 may be configured as or otherwise support a means for transmitting, to a set of the plurality of UEs, a message including a first mapping of a set of synchronization signal blocks to a first set of random access channel opportunities for a first subset of the plurality of UEs having a first capability and a second mapping of the set of synchronization signal blocks to a second set of random access channel opportunities for a second subset of the plurality of UEs having a second capability. The communications manager 1120 may be configured as or otherwise support a means for transmitting the set of synchronization signal blocks. The communications manager 1120 may be configured as or otherwise support a means for receiving, in response to transmitting the set of synchronization signal blocks, from one UE of the set of the plurality of UEs, a random access preamble in a random access channel opportunity selected from the first set of random access channel opportunities according to the first mapping based at least in part on the UEs having the first capability.

[0128]

[0137] By including or configuring the communications manager 1120 according to examples described herein, the device 1105 (e.g., a processor controlling or otherwise coupled to the receiver 1110, the transmitter 1115, the communications manager 1120, or a combination thereof) may support techniques for reduced processing, reduced power consumption, and more efficient utilization of communications resources. In particular, the base station 105 may facilitate more efficient random access procedures at the RedCap UE 115 and enable the RedCap UE 115 to efficiently select an RO in which to transmit a RACH preamble so that these random access procedures may be completed sooner, resulting in power savings and fewer wasted resources at the base station 105.

[0129]

[0138] 12 illustrates a block diagram 1200 of a device 1205 supporting RO selection for RedCap UEs according to an aspect of the disclosure. The device 1205 may be an example of an aspect of a device 1105 or a base station 105 as described herein. The device 1205 may include a receiver 1210, a transmitter 1215, and a communications manager 1220. The device 1205 may also include a processor. Each of these components may be in communication with each other (e.g., via one or more buses).

[0130]

[0139] The receiver 1210 may provide a means for receiving information, such as packets, user data, control information, or any combination thereof, associated with various information channels (e.g., control channels, data channels, information channels related to RO selection for RedCap UEs). The information may be passed to other components of the device 1205. The receiver 1210 may utilize a single antenna or a set of multiple antennas.

[0131]

[0140] The transmitter 1215 may provide a means for transmitting signals generated by other components of the device 1205. For example, the transmitter 1215 may transmit information such as packets associated with various information channels (e.g., a control channel, a data channel, an information channel related to RO selection for RedCap UEs), user data, control information, or any combination thereof. In some examples, the transmitter 1215 may be collocated with the receiver 1210 in a transceiver module. The transmitter 1215 may use a single antenna or a set of multiple antennas.

[0132]

[0141] The device 1205 or various components thereof may be an example of a means for performing various aspects of RO selection for RedCap UEs described herein. For example, the communications manager 1220 may include an RO configuration manager 1225, an SSB manager 1230, a random access preamble manager 1235, or any combination thereof. The communications manager 1220 may be an example of an aspect of the communications manager 1120 described herein. In some examples, the communications manager 1220, or various components thereof, may be configured to perform various operations (e.g., receiving, monitoring, transmitting) using or possibly cooperating with the receiver 1210, the transmitter 1215, or both. For example, the communications manager 1220 may receive information from the receiver 1210 and transmit information to the transmitter 1215, or may be integrated with the receiver 1210, the transmitter 1215, or both to receive information, transmit information, or perform various other operations described herein.

[0133]

[0142] The communications manager 1220 may support wireless communications in a base station according to examples disclosed herein. The RO configuration manager 1225 may be configured as, or may otherwise support, a means for transmitting a message to a set of UEs including a first mapping of a set of synchronization signal blocks to a first set of random access channel opportunities for a first subset of the plurality of UEs having a first capability and a second mapping of the set of synchronization signal blocks to a second set of random access channel opportunities for a second subset of the plurality of UEs having a second capability. The SSB manager 1230 may be configured as, or may otherwise support, a means for transmitting a set of synchronization signal blocks. The random access preamble manager 1235 may be configured as, or may otherwise support, a means for receiving, from a UE of the set of UEs in a random access channel opportunity selected from the first set of random access channel opportunities according to a first mapping based at least in part on the UEs having the first capability, in response to transmitting the set of synchronization signal blocks.

[0134]

[0143] FIG. 13 illustrates a block diagram 1300 of a communications manager 1320 supporting RO selection for RedCap UEs according to aspects of the disclosure. Communications manager 1320 may be an example of aspects of communications manager 1120, communications manager 1220, or both described herein. Communications manager 1320, or various components thereof, may be an example of a means for performing various aspects of RO selection for RedCap UEs described herein. For example, communications manager 1320 may include an RO configuration manager 1325, an SSB manager 1330, a random access preamble manager 1335, an RO validator 1340, an RO timing manager 1345, or any combination thereof. Each of these components may communicate directly or indirectly with each other (e.g., via one or more buses).

[0135]

[0144] The communications manager 1320 may support wireless communications in a base station according to examples disclosed herein. The RO configuration manager 1325 may be configured as, or may otherwise support, a means for transmitting a message to a set of UEs including a first mapping of a set of synchronization signal blocks to a first set of random access channel opportunities for a first subset of the plurality of UEs having a first capability and a second mapping of the set of synchronization signal blocks to a second set of random access channel opportunities for a second subset of the plurality of UEs having a second capability. The SSB manager 1330 may be configured as, or may otherwise support, a means for transmitting a set of synchronization signal blocks. The random access preamble manager 1335 may be configured as, or may otherwise support, a means for receiving, from a UE of the set of UEs in a random access channel opportunity selected from the first set of random access channel opportunities according to a first mapping based at least in part on the UEs having the first capability, in response to transmitting the set of synchronization signal blocks.

[0136]

[0145] In some examples, the RO configuration manager 1325 may send an indication of an uplink bandwidth portion for the UE to transmit a random access preamble based on a first capability of the UE. In some examples, the RO validator 1340 may be configured as or otherwise support a means for identifying a first set of random access channel opportunities from which the UE selects a random access channel opportunity based on a duration between a last-transmitted synchronization signal block of the set of synchronization signal blocks and each random access channel opportunity in the first set of random access channel opportunities satisfying a threshold duration.

[0137]

[0146] In some examples, the threshold duration meets a minimum time for a UE to transition from a receive mode to a transmit mode.

[0138]

[0147] In some examples, the UE is configured to utilize frequency division duplexing, and the minimum time for the UE to transition from a receive mode to a transmit mode is based on the numerology used for the random access preamble, the capabilities of the UE, or both.

[0139]

[0148] In some examples, the UE is configured to utilize time division duplexing, and the minimum time for the UE to transition from a receive mode to a transmit mode is based on the numerology used for the random access preamble, the capabilities of the UE, a radio frequency switching time at the UE, or a combination thereof.

[0140]

[0149] In some examples, identifying the first set of random access channel opportunities from which the UE selects a random access channel opportunity is further based on excluding a random access opportunity that precedes a synchronization signal block in the slot.

[0141]

[0150] In some examples, the threshold duration is equal to a duration configured in the UE for switching from a receive mode to a transmit mode in a time division duplex mode.

[0142]

[0151] In some examples, the RO timing manager 1345 may be configured with or otherwise support a means for sending an indication of the threshold duration to a UE based on the capabilities of the UE, and receiving a random access preamble in a random access channel opportunity is based on sending the indication of the threshold duration.

[0143]

[0152] In some examples, to support receiving a random access preamble, the random access preamble manager 1335 may be configured as or otherwise support a means for receiving a random access preamble during a random access channel opportunity based on a reference signal received power measurement of a synchronization signal block in a set of synchronization signal blocks satisfying a threshold.

[0144]

[0153] In some examples, the message includes a system information message or a radio resource control message. In some examples, the first capability of the UE includes a reduced capability.

[0145]

[0154] FIG. 14 illustrates a diagram of a system 1400 including a device 1405 supporting RO selection for RedCap UEs, according to aspects of the disclosure. The device 1405 may be or may include an example of a component of a device 1105, a device 1205, or a base station 105 as described herein. The device 1405 may wirelessly communicate with one or more base stations 105, UEs 115, or any combination thereof. The device 1405 may include components for two-way voice and data communication, including components for transmitting and receiving communications, such as a communications manager 1420, a network communications manager 1410, a transceiver 1415, an antenna 1425, a memory 1430, code 1435, a processor 1440, and an inter-station communications manager 1445. These components may be in electronic communication or may be coupled (e.g., operatively, communicatively, functionally, electronically, electrically) via one or more buses (e.g., a bus 1450).

[0146]

[0155] The network communications manager 1410 may manage communications with the core network 130 (e.g., via one or more wired backhaul links). For example, the network communications manager 1410 may manage the transfer of data communications for client devices, such as one or more UEs 115.

[0147]

[0156] In some cases, the device 1405 may include a single antenna 1425. However, in some other cases, the device 1405 may have two or more antennas 1425, which may be capable of simultaneously transmitting or receiving multiple wireless transmissions. The transceiver 1415 may communicate bidirectionally via one or more antennas 1425, a wired link, or a wireless link, as described herein. For example, the transceiver 1415 may represent a wireless transceiver and may communicate bidirectionally with another wireless transceiver. The transceiver 1415 may also include a modem for modulating packets and providing the modulated packets to the one or more antennas 1425 for transmission, and for demodulating packets received from the one or more antennas 1425. The transceiver 1415, or the transceiver 1415 and one or more antennas 1425, may be an example of the transmitter 1115, the transmitter 1215, the receiver 1110, the receiver 1210, or any combination or components thereof, as described herein.

[0148]

[0157] The memory 1430 may include RAM and ROM. The memory 1430 may store computer readable computer executable code 1435 including instructions that, when executed by the processor 1440, cause the device 1405 to perform various functions described herein. The code 1435 may be stored in a non-transitory computer readable medium, such as a system memory or another type of memory. In some cases, the code 1435 may not be directly executable by the processor 1440, but may (e.g., when compiled and executed) cause a computer to perform functions described herein. In some cases, the memory 1430 may include a BIOS, which may control basic hardware or software operations, such as interaction with peripheral components or devices, among other things.

[0149]

[0158] The processor 1440 may include an intelligent hardware device (e.g., a general-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, an FPGA, a programmable logic device, a discrete gate or transistor logic component, a discrete hardware component, or any combination thereof). In some cases, the processor 1440 may be configured to operate a memory array using a memory controller. In some other cases, the memory controller may be integrated with the processor 1440. The processor 1440 may be configured to execute computer-readable instructions stored in a memory (e.g., memory 1430) to cause the device 1405 to perform various functions (e.g., functions or tasks supporting RO selection for RedCap UEs). For example, the device 1405 or a component of the device 1405 may include a processor 1440 and a memory 1430 coupled to the processor 1440, where the processor 1440 and the memory 1430 are configured to perform various functions described herein.

[0150]

[0159] The inter-station communications manager 1445 may manage communications with other base stations 105 and may include a controller or scheduler for controlling communications with the UE 115 in cooperation with the other base stations 105. For example, the inter-station communications manager 1445 may coordinate scheduling for transmissions to the UE 115 for various interference mitigation techniques, such as beamforming or joint transmission. In some examples, the inter-station communications manager 1445 may provide an X2 interface in LTE / LTE-A wireless communications network technology to communicate between the base stations 105.

[0151]

[0160] The communications manager 1420 may support wireless communications at a base station according to examples disclosed herein. For example, the communications manager 1420 may be configured as or otherwise support a means for transmitting, to a set of a plurality of UEs, a message including a first mapping of a set of synchronization signal blocks to a first set of random access channel opportunities for a first subset of the plurality of UEs having a first capability and a second mapping of the set of synchronization signal blocks to a second set of random access channel opportunities for a second subset of the plurality of UEs having a second capability. The communications manager 1420 may be configured as or otherwise support a means for transmitting the set of synchronization signal blocks. The communications manager 1420 may be configured as or otherwise support a means for receiving, in response to transmitting the set of synchronization signal blocks, from one UE of the set of a plurality of UEs, a random access preamble in a random access channel opportunity selected from the first set of random access channel opportunities according to the first mapping based at least in part on the UEs having the first capability.

[0152]

[0161] By including or configuring the communications manager 1420 according to examples as described herein, the device 1405 may support techniques for reduced processing, reduced power consumption, and more efficient utilization of communications resources. In particular, the base station 105 may facilitate more efficient random access procedures at the RedCap UE 115 and enable the RedCap UE 115 to efficiently select an RO in which to transmit a RACH preamble so that these random access procedures may be completed sooner, resulting in power savings and fewer wasted resources at the base station 105.

[0153]

[0162] In some examples, the communications manager 1420 may be configured to perform various operations (e.g., receiving, monitoring, transmitting) using or otherwise cooperating with the transceiver 1415, one or more antennas 1425, or a combination thereof. Although the communications manager 1420 is shown as a separate component, in some examples, one or more functions described with respect to the communications manager 1420 may be supported or performed by the processor 1440, the memory 1430, the code 1435, or a combination thereof. For example, the code 1435 may include instructions executable by the processor 1440 that cause the device 1405 to perform various aspects of RO selection for RedCap UEs described herein, or the processor 1440 and the memory 1430 may be configured to perform or support such operations, as the case may be.

[0154]

[0163] FIG. 15 illustrates a flow chart illustrating a method 1500 of supporting RO selection for a RedCap UE according to an aspect of the disclosure. The operations of method 1500 may be performed by a UE or components thereof as described herein. For example, the operations of method 1500 may be performed by a UE 115 as described with reference to FIGS. 1-10. In some examples, the UE may execute a set of instructions to control functional elements of the UE to perform the described functions. Additionally or alternatively, the UE may perform aspects of the described functions using dedicated hardware.

[0155]

[0164] At 1505, the method may include receiving a message including a plurality of mappings of respective sets of synchronization signal blocks to respective sets of random access channel opportunities. The operations of 1505 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1505 may be performed by an RO configuration manager 925 as described with reference to FIG.

[0156]

[0165] At 1510, the method may include receiving one or more synchronization signal blocks of a set of synchronization signal blocks, the set of synchronization signal blocks being identified from a respective set of synchronization signal blocks according to one of a plurality of mappings determined based on the capabilities of the UE, the set of synchronization signal blocks being associated with a set of random access channel opportunities. The operations of 1510 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1510 may be performed by an SSB manager 930 described with reference to FIG. 9.

[0157]

[0166] At 1515, the method may include transmitting a random access preamble in a random access channel opportunity selected from a subset of a set of random access channel opportunities associated with one or more synchronization signal blocks, the random access channel opportunity being selected from the subset of the set of random access channel opportunities based on a duration between a last received downlink transmission and the random access channel opportunity satisfying a threshold duration. The operations of 1515 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1515 may be performed by a random access preamble manager 935 described with reference to FIG. 9.

[0158]

[0167] FIG. 16 illustrates a flow chart illustrating a method 1600 of supporting RO selection for RedCap UEs according to an aspect of the disclosure. The operations of method 1600 may be performed by a base station or components thereof as described herein. For example, the operations of method 1600 may be performed by a base station 105 as described with reference to FIGS. 1-6 and 11-14. In some examples, the base station may execute a set of instructions to control functional elements of the base station to perform the described functions. Additionally or alternatively, the base station may perform aspects of the described functions using dedicated hardware.

[0159]

[0168] At 1605, the method may include transmitting a message to a set of the plurality of UEs including a first mapping of a set of synchronization signal blocks to a first set of random access channel opportunities for a first subset of the plurality of UEs having a first capability and a second mapping of the set of synchronization signal blocks to a second set of random access channel opportunities for a second subset of the plurality of UEs having a second capability. The operations of 1605 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1605 may be performed by an RO configuration manager 1325 as described with reference to FIG. 13.

[0160]

[0169] At 1610, the method may include transmitting a set of synchronization signal blocks. The operations of 1610 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1610 may be performed by the SSB manager 1330 described with reference to FIG.

[0161]

[0170] At 1615, the method may include receiving, in response to transmitting the set of synchronization signal blocks, from a UE of the set of UEs, a random access preamble in a random access channel opportunity selected from a first set of random access channel opportunities according to a first mapping based at least in part on the UEs having a first capability. The operations of 1615 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1615 may be performed by a random access preamble manager 1335 described with reference to FIG. 13.

[0162]

[0171] The following provides a summary of aspects of the disclosure.

[0163]

[0172] Aspect 1: A method for wireless communications in a UE, the method including: receiving a message including a plurality of mappings of a respective set of synchronization signal blocks to a respective set of random access channel opportunities; receiving one or more synchronization signal blocks of the set of synchronization signal blocks, where the set of synchronization signal blocks is identified from the respective set of synchronization signal blocks according to one of a plurality of mappings determined based on capabilities of the UE, the set of synchronization signal blocks being associated with a set of random access channel opportunities; and transmitting a random access preamble in a random access channel opportunity selected from a subset of the set of random access channel opportunities associated with the one or more synchronization signal blocks, where the random access channel opportunity is selected from the subset of the set of random access channel opportunities based at least in part on a duration between a last received downlink transmission and the random access channel opportunity satisfying a threshold duration.

[0164]

[0173] Aspect 2: The method of aspect 1, further comprising receiving an indication of an uplink bandwidth portion for the UE to transmit the random access preamble based on a capability of the UE.

[0165]

[0174] Aspect 3: The method of any of aspects 1-2, further comprising identifying a subset of the set of random access channel opportunities from which to select a random access channel opportunity based at least in part on a duration between a last-received synchronization signal block of the one or more synchronization signal blocks and each random access channel opportunity in the subset of the set of random access channel opportunities satisfying a threshold duration.

[0166]

[0175] Aspect 4: The method of aspect 3, wherein identifying a subset of the set of random access channel opportunities from which to select a random access channel opportunity is further based at least in part on excluding a random access channel opportunity of the set of random access channel opportunities that precedes a synchronization signal block in the slot.

[0167]

[0176] Aspect 5: The method of any of aspects 3-4, wherein the UE is configured to operate in a half-duplex mode based at least in part on the capabilities of the UE, and the last received downlink transmission includes a control channel transmission, a data channel transmission, or a reference signal transmission.

[0168]

[0177] Aspect 6: A method as described in any of aspects 1 to 5, wherein receiving the message includes receiving in the message an indication of a subset of the set of random access channel opportunities from which to select a random access channel opportunity based at least in part on a duration between a last-received synchronization signal block of the one or more synchronization signal blocks and each random access channel opportunity in the subset of the set of random access channel opportunities satisfying a threshold duration.

[0169]

[0178] Aspect 7: The method according to any one of aspects 1 to 6, wherein the threshold duration satisfies a minimum time for the UE to transition from the receiving mode to the transmitting mode.

[0170]

[0179] Aspect 8: The method of aspect 7, wherein the UE is configured to utilize frequency division duplexing, and the minimum time for the UE to transition from a receive mode to a transmit mode is based at least in part on a numerology used for the random access preamble, the capabilities of the UE, or both.

[0171]

[0180] Aspect 9: A method as described in any of aspects 7 to 8, wherein the UE is configured to utilize time division duplexing, and the minimum time for the UE to transition from a receive mode to a transmit mode is based at least in part on a numerology used for the random access preamble, a capability of the UE, a radio frequency switching time at the UE, or a combination thereof.

[0172]

[0181] Aspect 10: The method according to any of aspects 1 to 9, wherein the threshold duration is equal to a duration configured in the UE for switching from a receive mode to a transmit mode in a time division duplex mode.

[0173]

[0182] Aspect 11: The method of any of aspects 1 to 10, further comprising receiving an indication of the threshold duration from the base station based at least in part on a capability of the UE, and the random access channel opportunity is selected at least in part based on receiving the indication of the threshold duration.

[0174]

[0183] Aspect 12: The method of any one of aspects 1 to 11, wherein the message includes a system information message or a radio resource control message.

[0175]

[0184] Example 13: The method of any one of Examples 1 to 12, wherein the capabilities of the UE include reduced capabilities.

[0176]

[0185] Aspect 14: The method according to any one of aspects 1 to 12, wherein the set of synchronization signal blocks is indicated by ssb-PositionsInBurst in system information block 1 or in ServingCellConfigCommon.

[0177]

[0186] Aspect 15: A method for wireless communication in an access network entity, the method comprising: transmitting a message to a plurality of UEs including a first mapping of a set of synchronization signal blocks to a first set of random access channel opportunities for a first subset of the plurality of UEs having a first capability and a second mapping of the set of synchronization signal blocks to a second set of random access channel opportunities; transmitting the set of synchronization signal blocks for the second subset of the plurality of UEs having the second capability; and in response to transmitting the set of synchronization signal blocks, receiving, from one UE of the plurality of UEs, a random access preamble in a random access channel opportunity selected from the first set of random access channel opportunities in accordance with the first mapping that is based at least in part on the UEs having the first capability.

[0178]

[0187] Aspect 16: The method of aspect 15, further comprising: transmitting an indication of an uplink bandwidth portion for the UE to transmit the random access preamble based at least in part on a first capability of the UE.

[0179]

[0188] Aspect 17: The method of aspect 15, further comprising: identifying a first set of random access channel opportunities from which the UE selects a random access channel opportunity based at least in part on a duration between a last-transmitted synchronization signal block of the set of synchronization signal blocks and each random access channel opportunity in the first set of random access channel opportunities satisfying a threshold duration.

[0180]

[0189] Aspect 18: The method of aspect 17, wherein the threshold duration satisfies a minimum time for a UE to transition from a receiving mode to a transmitting mode.

[0181]

[0190] Aspect 19: The method described in aspect 18, wherein the UE is configured to utilize frequency division duplexing, and the minimum time for the UE to transition from a receive mode to a transmit mode is based at least in part on a numerology used for the random access preamble, the capabilities of the UE, or both.

[0182]

[0191] Aspect 20: The method described in aspect 18, wherein the UE is configured to utilize time division duplexing, and the minimum time for the UE to transition from a receive mode to a transmit mode is based at least in part on a numerology used for the random access preamble, the capabilities of the UE, a radio frequency switching time at the UE, or a combination thereof.

[0183]

[0192] Aspect 21: A method as described in any of aspects 17 to 20, wherein identifying a first set of random access channel opportunities from which the UE selects a random access channel opportunity is further based at least in part on excluding random access opportunities that precede a synchronization signal block in the slot.

[0184]

[0193] Example 22: The method according to any one of Examples 17 to 21, wherein the threshold duration is equal to a duration configured in the UE for switching from a receive mode to a transmit mode in a time division duplex mode.

[0185]

[0194] Aspect 23: The method of any of aspects 17 to 22, further comprising transmitting an indication of the threshold duration to the UE based at least in part on a capability of the UE, and receiving the random access preamble during the random access channel opportunity is based at least in part on transmitting the indication of the threshold duration.

[0186]

[0195] Aspect 24: The method of any one of aspects 15 to 23, wherein the message includes a system information message or a radio resource control message.

[0187]

[0196] Example 25: The method of any one of examples 15 to 24, wherein the first capability of the UE includes a reduced capability.

[0188]

[0197] Aspect 26: An apparatus for wireless communication in a UE, comprising: a processor; a memory coupled to the processor; and instructions stored in the memory and executable by the processor to cause the apparatus to perform any of the methods of aspects 1-14.

[0189]

[0198] Example 27: An apparatus for wireless communication in a UE, the apparatus comprising at least one means for performing the method of any of Examples 1-14.

[0190]

[0199] Aspect 28: A non-transitory computer-readable medium storing code for wireless communication in a UE, the code including instructions executable by a processor to cause the processor to perform any of the methods of aspects 1-14.

[0191]

[0200] Aspect 29: An apparatus for wireless communication in a base station, comprising: a processor; a memory coupled to the processor; and instructions stored in the memory and executable by the processor to cause the apparatus to perform any of the methods of aspects 15 to 25.

[0192]

[0201] An apparatus for wireless communication in a base station, comprising at least one means for performing the method of any of aspects 15-25.

[0193]

[0202] Aspect 31: A non-transitory computer-readable medium storing code for wireless communication in a base station, the code including instructions executable by a processor to perform any of the methods of aspects 15-25.

[0194]

[0203] It should be noted that the methods described herein are descriptions of possible implementations, that the acts and steps may be rearranged or otherwise modified, and that other implementations are possible. Additionally, aspects from two or more of these methods may be combined.

[0195]

[0204] Although aspects of an LTE, LTE-A, LTE-A Pro, or NR system may be described as examples, and LTE, LTE-A, LTE-A Pro, or NR terminology may be used throughout much of the description, the techniques described herein may be applicable to other than LTE, LTE-A, LTE-A Pro, or NR networks. For example, the techniques described may be applicable to various other wireless communication systems, such as Ultra Mobile Broadband (UMB), Institute of Electrical and Electronics Engineers (IEEE) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, Flash-OFDM, and other systems and radio technologies not explicitly mentioned herein.

[0196]

[0205] The information and signals described herein may be represented using any of a wide variety of technologies and techniques. For example, the data, instructions, commands, information, signals, bits, symbols, and chips that may be referred to throughout the description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.

[0197]

[0206] The various example blocks and components described with respect to the disclosure herein may be implemented or performed using a general purpose processor, a DSP, an ASIC, a CPU, an FPGA or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general purpose processor may be a microprocessor, but alternatively, the processor may be any processor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices (e.g., a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration).

[0198]

[0207] The functions described herein may be implemented in hardware, software executed by a processor, firmware, or any combination thereof. If implemented in software executed by a processor, the functions may be stored on or transmitted over a computer-readable medium as one or more instructions or code. Other examples and implementations are within the scope of this disclosure and the appended claims. For example, due to the nature of software, the functions described herein may be implemented using software executed by a processor, hardware, firmware, hardwiring, or any combination thereof. Features implementing the functions may also be physically located in various locations, including being distributed such that parts of the functions are implemented in different physical locations.

[0199]

[0208] Computer-readable media includes both non-transitory computer storage media and communication media, including any medium that facilitates transfer of a computer program from one place to another. Non-transitory storage media may be any available medium that can be accessed by a general purpose or special purpose computer. By way of example, and not limitation, non-transitory computer-readable media may include RAM, ROM, electrically erasable programmable ROM (EEPROM), flash memory, compact disk (CD) ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other non-transitory medium that can be used to carry or store desired program code means in the form of instructions or data structures and that can be accessed by a general purpose or special purpose computer or a general purpose or special purpose processor. Also, any connection is properly termed a computer-readable medium. For example, if the software is transmitted from a website, server, or other remote source using coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technologies such as infrared, radio, and microwave, the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included within the definition of computer readable media. As used herein, disk and disc include CDs, laser discs, optical disks, digital versatile disks (DVDs), floppy disks, and Blu-ray discs, where disks typically reproduce data magnetically and discs reproduce data optically using lasers. Combinations of the above are also included within the scope of computer readable media.

[0200]

[0209] As used herein, including in the claims, "or" as used in a list of items (e.g., a list of items followed by a phrase such as "at least one of" or "one or more of") indicates an inclusive list, such as, for example, a list of at least one of A, B, or C means A or B or C or AB or AC or BC or ABC (i.e., A and B and C). Also, the phrase "based on" as used herein should not be construed as a reference to a closed set of conditions. For example, an exemplary step described as "based on condition A" may be based on both condition A and condition B without departing from the scope of the present disclosure. In other words, as used herein, the phrase "based on" is to be interpreted the same as the phrase "based at least in part on."

[0201]

[0210] The terms "determine" or "determining" encompass a wide variety of actions, and thus "determining" can include calculating, computing, processing, deriving, investigating, looking up (e.g., via a lookup in a table, database, or another data structure), ascertaining, and the like. "Determining" can also include receiving (e.g., receiving information), accessing (e.g., accessing data in a memory), and the like. "Determining" can also include resolving, selecting, choosing, establishing, and other similar acts.

[0202]

[0211] In the accompanying figures, similar components or features may have the same reference label. Furthermore, various components of the same type may be distinguished by following the reference label with a dash and a second label that distinguishes between the similar components. If only a first reference label is used herein, the description is applicable to any of the similar components having the same first reference label, regardless of the second reference label, or other subsequent reference labels.

[0203]

[0212] The description set forth herein with respect to the accompanying drawings describes exemplary configurations and does not necessarily represent all examples that may be implemented or fall within the scope of the claims. The term "example" as used herein means "serving as an example, instance, or illustration" and does not mean "preferred" or "advantageous over other examples." The detailed description includes specific details for the purposes of providing an understanding of the described techniques. However, these techniques may be practiced without these specific details. In some instances, known structures and devices are shown in block diagram form to avoid obscuring the concepts of the described examples.

[0204]

[0213] The description herein is provided to enable any person skilled in the art to make or use the disclosure. Various modifications of the disclosure will be apparent to those skilled in the art, and the general principles defined herein may be applied to other variations without departing from the scope of the disclosure. Thus, the disclosure is not limited to the examples and designs described herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for wireless communication in a user equipment (UE), comprising: receiving a message comprising a plurality of mappings of respective sets of synchronization signal blocks to respective sets of random access channel opportunities; receiving one or more synchronization signal blocks of a set of synchronization signal blocks, the set of synchronization signal blocks being identified from the respective set of synchronization signal blocks according to a mapping of the plurality of mappings determined at least in part based on a capability of the UE, the set of synchronization signal blocks being associated with a set of random access channel opportunities; transmitting a random access preamble in a random access channel opportunity selected from a subset of the set of random access channel opportunities associated with the one or more synchronization signal blocks, the random access channel opportunity being selected from the subset of the set of random access channel opportunities based at least in part on a duration between a last received downlink transmission and the random access channel opportunity satisfying a threshold duration; A method comprising:

2. The method of claim 1, further comprising receiving an indication of an uplink bandwidth portion for the UE to transmit the random access preamble based at least in part on the capabilities of the UE.

3. The method of claim 1, further comprising identifying the subset of the set of random access channel opportunities from which to select the random access channel opportunity based at least in part on a duration between a last-received synchronization signal block of the one or more synchronization signal blocks and each random access channel opportunity in the subset of the set of random access channel opportunities satisfying the threshold duration.

4. The method of claim 3, wherein identifying the subset of the set of random access channel opportunities from which to select the random access channel opportunity is further based at least in part on excluding random access opportunities of the set of random access channel opportunities that precede a synchronization signal block in a slot.

5. the UE is configured to operate in a half-duplex mode based at least in part on the capabilities of the UE; the last received downlink transmission comprises a control channel transmission, a data channel transmission, or a reference signal transmission. The method of claim 1.

6. The method of claim 1, further comprising receiving in the message an indication of the subset of the set of random access channel opportunities from which to select the random access channel opportunity based at least in part on a duration between a last-received synchronization signal block of the one or more synchronization signal blocks and each random access channel opportunity in the subset of the set of random access channel opportunities satisfying the threshold duration.

7. the threshold duration satisfies a minimum time for the UE to transition from a receive mode to a transmit mode; the UE is configured to utilize frequency division duplexing, and the minimum time for the UE to transition from the receive mode to the transmit mode is based at least in part on a numerology used for the random access preamble, a capability of the UE, or both; or 2. The method of claim 1, wherein the UE is configured to utilize time division duplexing, and the minimum time for the UE to transition from the receive mode to the transmit mode is based at least in part on a numerology used for the random access preamble, a capability of the UE, a radio frequency switching time at the UE, or a combination thereof.

8. The method of claim 1 , wherein the threshold duration is equal to a duration configured in the UE for switching from a receive mode to a transmit mode in a time division duplex mode.

9. The method of claim 1, further comprising receiving an indication of the threshold duration based at least in part on a capability of the UE, wherein the random access channel opportunity is selected based at least in part on receiving the indication of the threshold duration.

10. The method of claim 1 , wherein the capabilities of the UE comprise reduced capabilities.

11. The method of claim 1 , wherein the set of synchronization signal blocks is indicated by ssb-PositionsInBurst in System Information Block 1 or in ServingCellConfigCommon.

12. An apparatus for wireless communication comprising means configured to perform a method according to any one of claims 1 to 11.

13. 1. A method for wireless communication in an access network entity, comprising: transmitting a message to a plurality of user equipments (UEs), comprising a first mapping of a set of synchronization signal blocks to a first set of random access channel opportunities for a first subset of the plurality of UEs having a first capability, and a second mapping of the set of synchronization signal blocks to a second set of random access channel opportunities for a second subset of the plurality of UEs having a second capability; transmitting said set of synchronization signal blocks; receiving, in response to transmitting the set of synchronization signal blocks, from one UE of the plurality of UEs, a random access preamble in a random access channel opportunity selected from the first set of random access channel opportunities according to the first mapping based at least in part on the UEs having the first capability; A method comprising:

14. An apparatus for wireless communication comprising means configured to perform the method according to claim 13.

15. A computer program comprising program instructions which, when the program is executed by a computer, perform all the steps of the method of any one of claims 1 to 11 or 14.

Images