Network access by reduced-capability user equipment

Abstract

A user equipment (UE) can attempt to access a base station of a network. The UE receives a broadcast from a base station of a wireless network including a system information block (SIB) identifying a plurality of random access channel (RACH) subbands of an uplink (UL) bandwidth and which of the plurality of RACH subbands include physical random access channel (PRACH) resources. The base station selects one of the plurality of RACH subbands for PRACH transmission and selects a preamble from the selected RACH subband and transmits the preamble to the base station to initiate a RACH procedure.

Description

Background Technology

[0001] 5G New Radio (NR) wireless communication supports a variety of user equipment (UEs). For example, in addition to mobile phones, 5G NR also supports Internet of Things (IoT) devices, Industrial IoT (IIoT) devices, wearable devices, and more. Some of these devices are known as Reduced Cap (RedCap) UEs, which have varying wireless capabilities compared to other UEs. Summary of the Invention

[0002] Some exemplary aspects relate to a user equipment (UE) having a processor and a transceiver communicatively connected to the processor. The processor is configured to perform operations including: receiving a broadcast from a base station of a wireless network comprising a System Information Block (SIB) identifying multiple Random Access Channel (RACH) subbands of uplink (UL) bandwidth and which of the multiple RACH subbands includes Physical Random Access Channel (PRACH) resources; selecting one of the multiple RACH subbands for PRACH transmission; selecting a preamble from the selected RACH subband; and transmitting the preamble to the base station to initiate a RACH procedure.

[0003] Other exemplary aspects relate to a baseband processor configured to perform operations. These operations include receiving a broadcast from a base station comprising a System Information Block (SIB) that identifies multiple Random Access Channel (RACH) subbands of uplink (UL) bandwidth and which of the multiple RACH subbands includes Physical Random Access Channel (PRACH) resources; selecting one of the multiple RACH subbands for PRACH transmission; selecting a preamble from the selected RACH subband; and transmitting the preamble to the base station to initiate a RACH procedure. Attached Figure Description

[0004] Figure 1 An exemplary network arrangement based on various exemplary aspects is shown.

[0005] Figure 2 An exemplary UE is shown based on various exemplary aspects.

[0006] Figure 3 An exemplary base station configured to establish a connection with user equipment is shown, according to various exemplary aspects.

[0007] Figure 4 This is a diagram illustrating random access channel (RACH) subbands according to various exemplary aspects.

[0008] Figure 5This is a diagram illustrating the allocation of physical RACH (PRACH) resources in RACH subbands according to various exemplary aspects.

[0009] Figure 6 This is a diagram illustrating the PRACH format available for RACH subbands according to various exemplary aspects.

[0010] Figure 7 This is a flowchart illustrating a method for selecting PRACH resources based on various exemplary aspects.

[0011] Figure 8 This is a diagram illustrating the determination of repeated messages 2 (Msg2) and 3 (Msg3) according to various exemplary aspects.

[0012] Figure 9 This is a diagram illustrating random access responses according to various exemplary aspects. Detailed Implementation

[0013] The exemplary aspects can be further understood with reference to the following description and related figures, wherein similar elements have the same reference numerals. The exemplary aspects describe a manner in which a network access procedure is performed by a degraded user equipment (RedCap UE).

[0014] The exemplary aspects are described with reference to networks including 5G New Radio (NR) radio access technology (RAT). However, the exemplary aspects can be implemented in other types of networks using the principles described herein.

[0015] Exemplary aspects are also described with respect to the UE. However, the use of the UE is for illustrative purposes only. The exemplary aspects can be utilized with any electronic component that can establish a connection to a network and is configured with hardware, software, and / or firmware for exchanging information and data with that network. Therefore, the UE described herein is used to represent any electronic component.

[0016] As mentioned above, there are various types of UEs, each with different capabilities to connect to the 5G NR network. However, in a given area, it may not be beneficial to have different UEs with different capabilities camped in the same cell, because UEs with reduced capabilities can utilize different parameters for wireless communication (e.g., bandwidth portion, data rate, etc.) compared to other UEs (e.g., mobile phones, laptops, etc.), which means that the cell will need to adjust its communication for all types of UEs.

[0017] Before describing exemplary aspects, several examples of RedCap UEs and their characteristics will be described. In the first example, devices in an industrial environment, such as temperature or humidity sensors, can be connected industrial devices. However, such devices are stationary, not latency-critical, and their capabilities and hardware are relatively uncomplicated. These devices typically do not require low-latency data exchange provided by Ultra-Reliable Low-Latency Communication (URLLC) or IIoT. These devices are also expected to operate in the field for many years with little or no maintenance, including battery replacement. Therefore, power-saving operation may be critical for these types of devices.

[0018] Another example of a RedCap-type device with capabilities different from other UEs is a surveillance device (e.g., a camera). These devices are similar to those in the first example because they are typically stationary and do not have strict latency requirements. However, they can differ from the first example because these devices can be connected to a permanent power source (although it is not required) and can have much higher upload data rates than many other UEs due to, for example, the video upload feeds they provide.

[0019] Another example of a RedCap-type device with capabilities distinct from many other UEs is the wearable device. Unlike the examples mentioned above, wearable devices typically offer mobility similar to mobile phones and operation associated with the same types of applications that can be run on mobile phones. However, due to their smaller form factor resulting in smaller batteries, these devices have more stringent power-saving requirements than mobile phones.

[0020] These examples of different UE types are by no means an exhaustive list of 5G-enabled devices, but rather provided as examples of the varying capabilities of different UEs to connect to a 5G NR wireless network at any given time. Devices considered RedCap devices may be subject to bandwidth limitations provided to them by standards (e.g., 3GPP standards) or individual network providers. This reduced bandwidth may result in a loss of coverage area. While time-slot aggregation or repetition can be used to compensate for this coverage loss, these options are not supported prior to the UE's Radio Resource Control (RRC) configuration. Therefore, attaching a RedCap UE to the cell's Random Access Channel (RACH) procedure is necessary.

[0021] According to some exemplary aspects, 5G NR networks can divide the bandwidth portion of a component carrier (CC) into smaller bandwidth subbands and allocate physical RACH (PRACH) resources for the RACH process among one or more subbands. This advantageously reduces the overhead resources allocated for servicing RedCap devices while ensuring that these RedCap devices can still successfully attach to the cell.

[0022] Figure 1 An exemplary network arrangement 100 according to various exemplary aspects is illustrated. The exemplary network arrangement 100 includes a UE 110. It should be noted that any number of UEs may be used in the network arrangement 100. Those skilled in the art will understand that the UE 110 may alternatively be any type of electronic component configured to communicate via a network, such as a mobile phone, tablet, desktop computer, smartphone, phablet, embedded device, wearable device, Internet of Things (IoT) device, etc. It should also be understood that a practical network arrangement may include any number of UEs used by any number of users. Therefore, for illustrative purposes, only an example with a single UE 110 is provided.

[0023] UE 110 can be configured to communicate with one or more networks. In the example of network arrangement 100, the networks with which UE 110 can wirelessly communicate are 5G New Radio (NR) Radio Access Network (5G NR-RAN) 120, LTE Radio Access Network (LTE-RAN) 122, and Wireless Local Area Network (WLAN) 124. However, it should be understood that UE 110 can also communicate with other types of networks, and UE 110 can also communicate with networks via wired connections. Therefore, UE 110 may include a 5G NR chipset communicating with 5G NR-RAN 120, an LTE chipset communicating with LTE-RAN 122, and an ISM chipset communicating with WLAN 124.

[0024] 5G NR-RAN 120 and LTE-RAN 122 can be parts of cellular networks that can be deployed by cellular providers (e.g., Verizon, AT&T, Sprint, T-Mobile, etc.). These networks 120, 122 can include, for example, cells or base stations (NodeB, eNodeB, HeNB, eNBS, gNB, gNodeB, macrocell base stations, microcell base stations, small cell base stations, femtocell base stations, etc.) configured to send and receive traffic from UEs equipped with appropriate cellular chipsets. WLAN 124 can include any type of wireless local area network (WiFi, hotspot, IEEE 802.11x network, etc.).

[0025] UE 110 can connect to 5G NR-RAN 120 via gNB 120A and / or gNB 120B. During operation, UE 110 can be within range of multiple gNBs. Therefore, simultaneously or alternatively, UE 110 can connect to 5G NR-RAN 120 via gNBs 120A and 120B. Additionally, UE 110 can communicate with eNB 122A of LTE-RAN 122 to transmit and receive control information for downlink and / or uplink synchronization relative to the 5G NR-RAN 120 connection.

[0026] Those skilled in the art will understand that any relevant procedures can be performed for UE 110 to connect to 5G NR-RAN 120. For example, as described above, 5G NR-RAN 120 can be associated with a specific cellular provider, where UE 110 and / or its user have protocol and credential information (e.g., stored on a SIM card). Upon detecting the presence of 5G NR-RAN 120, UE 110 can transmit the corresponding credential information to associate with 5G NR-RAN 120. More specifically, UE 110 can be associated with a specific base station (e.g., gNB 120A of 5G NR-RAN 120).

[0027] In addition to networks 120, 122, and 124, network deployment 100 also includes a cellular core network 130, an Internet 140, an IP Multimedia Subsystem (IMS) 150, and a network service backbone 160. The cellular core network 130 (e.g., NR's 5GC) can be viewed as an interconnected collection of components that manage the operation and traffic of the cellular network. The cellular core network 130 also manages the traffic flowing between the cellular network and the Internet 140.

[0028] IMS150 can generally be described as an architecture for delivering multimedia services to UE 110 using the IP protocol. IMS150 can communicate with cellular core network 130 and Internet 140 to provide multimedia services to UE 110. Network service backbone 160 communicates directly or indirectly with Internet 140 and cellular core network 130. Network service backbone 160 can generally be described as a set of components (e.g., servers, network storage deployments, etc.) that implement a set of services that can be used to extend the functionality of UE 110 to communicate with various networks.

[0029] Figure 2 An exemplary UE 110 is shown according to various exemplary aspects. Reference will be made to... Figure 1 The network layout 100 is used to describe UE 110. For the purposes of this discussion, UE 110 may be considered a red-capped UE. However, it should be noted that UE 110 can represent any electronic device and may include processor 205, memory layout 210, display device 215, input / output (I / O) device 220, transceiver 225, and other components 230. Other components 230 may include, for example, audio input devices, audio output devices, batteries providing a limited power source, data acquisition devices, ports for electrically connecting UE 110 to other electronic devices, one or more antenna panels, etc. For example, UE 110 may be coupled to industrial equipment via one or more ports.

[0030] Processor 205 may be configured to execute multiple engines of UE 110. For example, an engine may include RACH management engine 235. As will be described in more detail below, RACH management engine 235 may perform various operations related to the RACH process, such as processing System Information Block 1 (SIB1) to determine the subband carrying PRACH resources, selecting one of the subbands for PRACH transmission, etc.

[0031] The engine described above, as an application (e.g., a program) executed by processor 205, is merely exemplary. The functionality associated with the engine may also be represented as a separate, integrated component of UE 110, or as a modular component coupled to UE 110, such as an integrated circuit with or without firmware. For example, the integrated circuit may include input circuitry for receiving signals and processing circuitry for processing signals and other information. The engine may also be embodied as a single application or multiple separate applications. Furthermore, in some UEs, the functionality described for processor 205 is distributed among two or more processors, such as a baseband processor and an application processor. Exemplary aspects may be implemented according to any of these or other configurations of the UE.

[0032] Memory arrangement 210 may be a hardware component configured to store data related to operations performed by UE 110. Display device 215 may be a hardware component configured to display data to a user, while I / O device 220 may be a hardware component enabling user input. Display device 215 and I / O device 220 may be separate components or may be integrated together (such as a touchscreen). Transceiver 225 may be a hardware component configured to establish connections with 5G NR-RAN 120, LTE-RAN 122, WLAN 124, etc. Therefore, transceiver 225 may operate on multiple different frequencies or channels (e.g., a continuous set of frequencies).

[0033] Figure 3 An exemplary network cell, in this example gNB 120A, is shown according to various exemplary aspects. gNB120A can represent any access node of a 5G NR network that UE 110 can use to establish a connection. Figure 3 The gNB 120A shown can also represent gNB 120B.

[0034] The gNB 120A may include a processor 305, a memory arrangement 310, input / output (I / O) devices 320, a transceiver 325, and other components 330. These other components 330 may include, for example, a power supply, data acquisition devices, and ports for electrically connecting the gNB 120A to other electronic devices.

[0035] Processor 305 can be configured to execute multiple engines of gNB 120A. For example, an engine may include RACH management engine 335 for performing operations including managing the RACH procedure for attaching RedCap UEs to gNB 120A. An example of managing the RACH procedure will be described in more detail below.

[0036] The engine described above, as an application (e.g., a program) executed by processor 305, is merely exemplary. The functionality associated with the engine may also be represented as a separate integrated component of gNB 120A, or as a modular component coupled to gNB 120A, such as an integrated circuit with or without firmware. For example, the integrated circuit may include input circuitry for receiving signals and processing circuitry for processing signals and other information. Furthermore, in some gNBs, the functionality described for processor 305 is split among multiple processors (e.g., a baseband processor, an application processor, etc.). Exemplary aspects may be implemented according to any of these or other configurations of the gNB.

[0037] Memory 310 may be a hardware component configured to store data related to operations performed by UE 110, 112. I / O device 320 may be a hardware component or port enabling a user to interact with gNB 120A. Transceiver 325 may be a hardware component configured to exchange data with UE 110 and any other UE in the system. Transceiver 325 may operate on a variety of different frequencies or channels (e.g., a set of consecutive frequencies). Therefore, transceiver 325 may include one or more components (e.g., radio components) to enable data exchange with various networks and UEs.

[0038] Figure 4 This is a diagram illustrating the Random Access Channel (RACH) subband 402 according to various exemplary aspects. The RACH subband set 402 used for the RedCap RACH procedure can span a subset configured for a given cell or the entire downlink (DL) component carrier (CC) bandwidth. Figure 4 The exemplary subband configuration shown includes four subbands (0, 1, 2, and 3), each subband having... One resource block. The value of can be determined in several ways. For example, in some aspects, This can be configured via SIB1 received by RedCap UE 110. For example, the value... This can be broadcast via gNB 120A in the SIB1 system information. In some respects, The value can alternatively be a function of the DLCC bandwidth. In some respects, The value can be alternatively set by a standard (e.g., a 3GPP standard) and can be based on the bandwidth capabilities of the RedCap UE110 (e.g., 10MHz or 20MHz for frequency range 1; and 50MHz or 100MHz for frequency range 2) and the subcarrier spacing “u”. For example, The value of the subcarrier spacing "u" for subcarrier spacings of 0, 1, and 2 can be 100 / 50 / 25, or for subcarrier spacings of 2, 3, and 4 it can be 136 / 68.

[0039] Figure 5 This is a diagram illustrating the allocation of physical RACH (PRACH) 504 resources in RACH subbands 502 according to various exemplary aspects. In some aspects, the set 502 of RACH subbands including PRACH resources 504 can be identified by the `rach-ConfigCommon` information element (IE) in SIB1 broadcast by gNB 122A. An exemplary abstract syntax symbol (ASN.1) signaling indicating a set of RACH subbands including PRACH resources can be `RACHSubBandList::= BITSTRING(SIZE(maxNrofRACHSubBands))`, where "BITSTRING" is a binary string, where a value of 0 indicates that the corresponding subband does not include PRACH resources, and a value of 1 indicates that the corresponding subband includes PRACH resources. Figure 5 In the example shown, BITSTRING will have a value of 01110, indicating that the middle three subbands (subband indices 1, 2 and 3) of the five subbands 502 include PRACH resource 504.

[0040] In some respects, various methods can be used to indicate the frequency domain start position of the corresponding PRACH resource 504 in each RACH subband 502. For example, in some respects, a single offset value 500 The RRC signaling is configured relative to the starting physical resource block (PRB) of each associated RACH subband 502 and is used to determine the PRACH resource location within each subband. For example, the corresponding offset 510. 520 and 530 They will all have the same value (e.g., In some respects, individual offset values This can be optionally applied to each corresponding sub-band. For example, the corresponding offset is 510. 520 and 530 They can each have different values. In some respects, the individual offset is 550. 570 and 580 Alternatively, it can be configured with respect to a common reference point, such as the starting resource block (RB) of the UL BWP. Having different offset values ​​allows the gNB 120A to transmit other UL transmission resources during the offset period.

[0041] Figure 6 Figures illustrate PRACH formats 600 and 610 available for RACH subbands according to various exemplary aspects. In some aspects, different PRACH formats can be configured for PRACH resources in different RACH subbands. In such aspects, a separate prach-ConfigurationIndex IE can be used for each subband to identify the PRACH format for the corresponding subband. Since different PRACH formats have correspondingly different coverage properties, using different PRACH formats advantageously allows for efficient utilization of network resources. For example, given a subcarrier spacing of 15 kHz, the maximum cell range associated with PRACH format A3 (6 symbols) and PRACH format B4 (12 symbols) can reach 3,516 meters and 3,867 meters respectively, which can be used by UEs at the cell edge to improve initial access performance. On the other hand, for UEs at the cell center, PRACH formats A1 / B1 with 2 symbols are sufficient to meet the initial access performance requirements.

[0042] In some respects, the PRACH format can be based on the location of RedCap UE 110 within the cell (e.g., how far it is from the gNB). The larger the number of symbols in the PRACH resource, the greater the number of repetitions (e.g., 6 symbols = 6 repetitions). Greater repetitions ensure improved carrier performance by guaranteeing that communication from RedCap UE 110 successfully reaches gNB 120A and that the RACH process is successfully completed. Figure 6 Examples of different PRACH formats for two RA subbands 600 and 610 are shown by using a separate prach-ConfigurationIndex IE for each subband.

[0043] Figure 7 This is a flowchart illustrating a method 700 for selecting PRACH resources according to various exemplary aspects. At 705, RedCap UE 110 obtains the RACH subband configuration and prach-ConfigurationIndex of its serving cell. This information, in the SIB, instructs RedCap UE 110 to receive and notify the UE from gNB 120A which RACH subbands include PRACH resources, the PRACH format, and the periodicity of the corresponding RACH subbands with PRACH resources.

[0044] In some respects, SIB1 may include additional configuration information in addition to the RACH subband configuration and prach-ConfigurationIndex. In some respects, this additional information may be provided separately on a per-RACH subband basis. In some respects, such additional information may include one or more of the following: (1) the Random Access Response (RAR) window size (ra-ResponseWindowSize), (2) the power ramp factor, (3) the initial preamble power, (4) the maximum number of Message 3 (Msg3) Hybrid Automatic Repeat Request (HARQ) transmissions, (5) the Contention Resolution Timer (mac-ContentionResolutionTimer), (6) the number of attempts per RACH subband, and / or (7) the number of Msg2 / Msg3 / Msg4 repetitions. Regarding the RAR window size, in some respects, the window size may be a function of the RACH repetition level. For example, the window size may be based on the PRACH format selected for each corresponding RACH subband.

[0045] Regarding the number of repetitions of Msg2 / Msg3 / Msg4, the number of repetitions can be based on the PRACH format. For example, in the case of PRACH format A3 which includes 6 symbols (e.g., exemplary PRACH format 600), the number of repetitions can correspond to the number of symbols (6 repetitions).

[0046] In some respects, the number of times each message is repeated (Msg2 / Msg3 / Msg4) can be alternatively defined as K = K PRACH +Δ, where K is the number of symbols in the PRACH format and Δ is a constant configured in SIB transmission. It should be noted that a different Δ value can be configured for Msg2 / Msg4 than for Msg3. Figure 8 This is a diagram illustrating the determination of repeated messages 2 (Msg2) and 3 (Msg3) according to various exemplary aspects. Figure 8 Assume the configured Δ value is 0. Thus, given a PRACH format 802 with 3 symbols, the PDCCH repetition schedule for Msg2 804, Msg2 repetition 806, and Msg3 repetition 808 are all equal to 3. However, as mentioned above, these repetition values ​​can vary depending on the configured Δ value.

[0047] In some respects, the number of repetitions of Msg3 can be explicitly indicated in Msg2 (RAR). Figure 9This is a diagram illustrating a RAR 900 according to various exemplary aspects. In such aspects, the number of repetitions of Msg3 can be determined by the R value 902 of the RAR. In some aspects, the R value 902 may indicate one of two possible repetition values. In some aspects, a predetermined number of bits of the uplink (UL) grant 904 in the RAR may alternatively indicate one of a predetermined set of repetition values. In the aspect where the number of repetitions of Msg3 is configured by Msg2 as explained above, the number of repetitions of Msg2 and Msg4 can be based on the PRACH format as explained above.

[0048] In some respects, the transmission power of PRACH and Msg3 can be adjusted based on the corresponding repetition of the selected PRACH format. In this respect, sudden jumps in the cumulative power level caused by the repetition level ramp are advantageously avoided, and the effects of near-far effects are thus reduced.

[0049] return Figure 7 In addition to the configuration information provided at 705 discussed above, in some respects, the list of Reference Signal Received Power (RSRP) thresholds can also be configured in the SIB as "RSRP-ThresholdsPrachInfoList-r17::=SEQUENCE(SIZE(1..N))OF RSRP-Range". Up to N RSRP thresholds can be configured. As described below, at 710, the RSRP thresholds will be used for the selection of RACH subbands.

[0050] At 710, RedCap UE 110 selects the RACH subband for PRACH transmission based on its DL RSRP measurement. RedCap UE 110 estimates path loss by averaging the RSRP measurement based on a reference signal such as a SIB or Channel State Information (CSI) reference signal. The measured RSRP is then compared to an RSRP threshold configured in the SIB received at 705 to select the RACH subband. In some respects, RedCap UE 110 measures the RSRP of the strongest detected synchronization signal block (SSB). If the measured RSRP is less than the RSRP threshold for enhanced coverage level (PRACH format) N and the UE supports (e.g., is capable of supporting) enhanced coverage level N, then at 710, the UE selects the RACH subband associated with coverage level N. However, if multiple RACH subbands provide PRACH resources for the same coverage level, RedCap UE 110 randomly selects one of these subbands. Alternatively, in some respects, different selection probabilities can be configured for each RACH subband.

[0051] At 715, RedCap UE 110 randomly selects a preamble from the chosen RACH subband and transmits it to gNB 122A to initiate the RACH procedure. In some respects, for each RACH subband, RedCap UE 110 applies a power ramp to all PRACH repetition levels except the highest repetition level. In some respects, when RedCap UE 110 receives a RAR (Msg2) but contention resolution fails, the UE uses its current repetition level until the maximum number of attempts for that level is reached. That is, if the UE contention resolution fails (Msg3 collision), the UE can choose an alternative PRACH format and use the current repetition level until the maximum number of attempts is reached. However, randomly selecting an alternative PRACH format whenever the UE contention resolution fails is wasteful of resources because there is no guarantee that the UE will successfully use these PRACH formats.

[0052] Those skilled in the art will understand that the exemplary aspects described above can be implemented with any suitable software or hardware configuration or combination thereof. Exemplary hardware platforms for implementing the exemplary aspects may include, for example, Intel x86-based platforms with compatible operating systems, Windows OS, Mac platforms and MAC OS, and mobile devices with operating systems such as iOS, Android, etc. In other examples, exemplary aspects of the methods described above may be embodied as programs comprising lines of code stored on a non-transitory computer-readable storage medium, which, at compile time, can be executed on a processor or microprocessor.

[0053] Although this patent application describes various combinations of aspects, each with different features, those skilled in the art will understand that any feature of one aspect can be combined with features of other aspects or features that are not functionally or logically inconsistent with the operation or function of the device of the aspect disclosed in this invention in any manner not disclosed to be denied.

[0054] As is widely recognized, the use of personally identifiable information should comply with privacy policies and practices that are generally accepted to meet or exceed industry or governmental requirements for protecting user privacy. Specifically, personally identifiable information data should be managed and processed to minimize the risk of unintentional or unauthorized access or use, and the nature of authorized use should be clearly explained to users.

[0055] It will be apparent to those skilled in the art that various modifications can be made to this disclosure without departing from its spirit or scope. Therefore, this disclosure is intended to cover all modifications and variations thereof, provided that such modifications and variations are within the scope of the appended claims and their equivalents.

Claims

1. A capability to reduce RedCap user equipment (UE), comprising: A processor configured to perform operations including: The system receives a broadcast from a base station of the wireless network, including a System Information Block (SIB), which identifies multiple Random Access Channel (RACH) subbands of the uplink UL bandwidth, which of the multiple RACH subbands includes Physical Random Access Channel (PRACH) resources, and multiple Information Elements (IEs), wherein each of the multiple IEs identifies a PRACH format for each of the multiple subbands based on the location of the RedCap UE within the cell. Select one of the plurality of RACH subbands for PRACH transmission; Select a preamble from the selected RACH subband and transmit the preamble to the base station to initiate the RACH process; Receive a Random Access Response (RAR) from the base station; and The number of times message 3Msg3 is repeated is determined based on the RAR, wherein the number of times Msg3 is repeated is based on a predetermined number of bits of UL authorization in the RAR, the predetermined number of bits of UL authorization in the RAR indicating one of a predetermined set of repeat values ​​for Msg3; a transceiver is communicatively connected to the processor.

2. The RedCap UE of claim 1, wherein the SIB further comprises one or more offset values, the one or more offset values ​​indicating the starting position of each PRACH resource in a corresponding RACH subband that includes the PRACH resource.

3. The RedCap UE of claim 2, wherein the one or more offset values ​​are a single value.

4. The RedCap UE of claim 2, wherein the one or more offset values ​​include a plurality of values ​​corresponding to a RACH subband including the PRACH resource.

5. The RedCap UE of claim 4, wherein the individual value is with respect to a common reference point in the UL bandwidth.

6. The RedCap UE of claim 1, wherein the SIB further includes a PRACH format configuration.

7. The RedCap UE of claim 6, wherein the PRACH format configuration is different for each PRACH resource in the PRACH resources.

8. The RedCap UE according to claim 6, wherein the SIB further includes a repetition count configuration for the number of times message 2Msg2 is repeated, the number of times message 3Msg3 is repeated, and the number of times message 4Msg4 is repeated.

9. The RedCap UE according to claim 8, wherein the number of repetitions of Msg2, Msg3 and Msg4 is equal to (1) the sum of the number of symbols corresponding to the PRACH format of the corresponding RACH subband and (2) the constant configured by the SIB.

10. The RedCap UE of claim 1, wherein the SIB further includes a list of reference signal received power (RSRP) thresholds.

11. The RedCap UE of claim 10, wherein, in order to select one of the plurality of RACH subbands for the PRACH transmission, the operation further comprises: Measure the RSRP of the reference signal; as well as The measured RSRP is compared with the RSRP threshold.

12. A method for a baseband processor, the baseband processor being configured to perform operations, the operations including: The system receives a broadcast from the base station including a System Information Block (SIB), which identifies multiple Random Access Channel (RACH) subbands of the uplink UL bandwidth, which of the multiple RACH subbands includes Physical Random Access Channel (PRACH) resources, and multiple Information Elements (IEs), wherein each of the multiple IEs identifies the PRACH format for each of the multiple subbands based on the location of the User Equipment (UE) within the cell, according to the Capability Degradation RedCap. Select one of the plurality of RACH subbands for PRACH transmission; Select a preamble from the selected RACH subband and transmit the preamble to the base station to initiate the RACH process; Receive a Random Access Response (RAR) from the base station; as well as The number of times message 3Msg3 is repeated by the RedCap UE is determined based on the RAR, wherein the number of times Msg3 is repeated is based on a predetermined number of bits in the RAR that are UL-authorized, and the predetermined number of bits in the RAR that are UL-authorized indicate one of a set of predetermined repeat values ​​for Msg3.

13. The method of claim 12, wherein the SIB further comprises one or more offset values, the one or more offset values ​​indicating the starting position of each PRACH resource in a corresponding RACH subband that includes the PRACH resource.

14. The method of claim 12, wherein the SIB further includes a PRACH format configuration.

15. The method of claim 14, wherein the PRACH format configuration is different for each PRACH resource in the PRACH resources.

16. The method of claim 14, wherein the SIB further comprises a repetition configuration for the number of times message 2Msg2 is repeated, the number of times message 3Msg3 is repeated, and the number of times message 4Msg4 is repeated.

17. The method of claim 16, wherein the number of repetitions of Msg2, Msg3 and Msg4 is equal to the sum of (1) the number of symbols corresponding to the PRACH format of the corresponding RACH subband and (2) the constant configured by the SIB.

18. The method of claim 16, wherein the number of times Msg3 is repeated is explicitly indicated in the random access response (RAR) of Msg2.

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