WO2018144936A1

WO2018144936A1 - Allocation of uplink resources based on user equipment power classes

Info

Publication number: WO2018144936A1
Application number: PCT/US2018/016728
Authority: WO
Inventors: Anatoliy Toliy IOFFE; Xinrong Wang; Debdeep CHATTERJEE; Marta Martinez TARRADELL; Tang Yang; Seau Lim
Original assignee: Intel IP Corporation
Priority date: 2017-02-03
Filing date: 2018-02-02
Publication date: 2018-08-09
Also published as: DE112018000234T5

Abstract

Techniques described herein may be used to ensure that Physical Random Access Channel (PRACH) uplink (UL) resources are properly allocated to User Equipment (UE) by taking into account the power class of the UE. The power class of a UE may correspond to transmission power configurations or capabilities of the UE.

Description

ALLOCATION OF UPLINK RESOURCES BASED ON USER EQUIPMENT POWER

CLASSES

RELATED APPLICATIONS

The present application claims the benefit of U.S. Provisional Patent Application No.

62/454,670, which was filed on February 3, 2017, the contents of which are hereby incorporated by reference as though fully set forth herein.

BACKGROUND

An emerging wireless standard for wireless cellular networks is known as 5G New Radio (NR). The specifications for 5G NR are standardized as part of the Third Generation Partnership Project (3GPP) specifications with a goal of making wireless broadband performance comparable to that of wireline network connectivity. In 5G NR, a new Radio Access

Technology (RAT), beyond the Long-Term Evolution (LTE) standard, is used.

An aspect of this RAT relates to procedures whereby User Equipment connect to Radio Access Network (RAN) nodes, such as enhanced Node B (eNBs). An example of such a procedure includes a Random Access Procedure, whereby a UE initially contacts an eNB to obtain synchronization information, system information, and temporary resources for communicating with the eNB to establish a more permanent connection with the eNB and register with a core network. As the RAT for 5G NR may involve more broadband UEs (such as smartphones, tablet computers, etc.) in addition to other types of UEs (such as enhanced

Machine-Type-Communication (eMTC) devices, enhanced Narrowband Internet-of-Things (eNB IoT) devices, etc.) the precise manner in which a UE communicates with an eNB may vary.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments described herein will be readily understood by the following detailed description in conjunction with the accompanying drawings. To facilitate this description, like reference numerals may designate like structural elements. Embodiments are illustrated by way of example and not by way of limitation in the figures of the accompanying drawings.

Fig. 1 is a diagram conceptually illustrating an example architecture relating to 5G NR functionality;

Fig. 2 is a flow chart illustrating an example process for allocating uplink (UL) resources based on a UE power class;

Fig. 3 is a diagram of an example for determining UL resources by modifying a

Reference Signals Received Power (RSRP) thresholds based on a UE power class; Fig. 4 is a diagram of an example for determining UL resources for UEs corresponding to different power classes;

Fig. 5 illustrates example components of a device in accordance with some

embodiments;

Fig. 6 illustrates example interfaces of baseband circuitry in accordance with some embodiments; and

Fig. 7 is a block diagram illustrating components, according to some example embodiments, able to read instructions from a machine-readable or computer-readable medium (e.g., a non-transitory machine-readable storage medium) and perform any one or more of the methodologies discussed herein.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

The techniques described herein may be used to ensure that uplink (UL) resources of a Physical Random Access Channel (PRACH) are properly allocated to User Equipment (UE) by allocating the UL resources according to the power class of each UE. In a traditional scenario, when a UE attempts to connect to a RAN node (e.g. , a base station), the UE may acquire system information transmitted by the RAN node to UEs in the area. The system information may include instructions for initiating a Random Access Channel (RACH) procedure, whereby the UE may connect to the RAN node and register with the network.

The system information may include Physical RACH (PRACH) profiles associated with PRACH resources for initiating a RACH procedure with the RAN node (e.g. , by transmitting a RACH Msgl request to the RAN node). Examples of the information included, or otherwise associated with the PRACH profiles, may include preamble length, subframe allocations, number of UL transmission repetitions, etc. Additionally, each PRACH profile may be associated with a signal strength threshold to enable the UE to select an appropriate PRACH profile.

As such, to select a PRACH profile, the UE may determine, measure, estimate, etc., the signal strength of a references signal from the RAN node (e.g. , a Reference Signals Received Power (RSRP) signal) and may compare the measured signal strength to the signal strength thresholds associated with the PRACH profiles to determine the PRACH profile (and therefore the PRACH resources) for communicating with the RAN node. The UE may then proceed to initiate and complete a RACH procedure using the UL resources indicated by the selected PRACH profile. This approach to allocating UL resources to UEs may have certain drawbacks since selection of the PRACH profile is based on the measured signal strength without regard to the power class (e.g., the transmission tendencies and capabilities) of different types of UEs. For example, some types of UEs, such as Narrow Band Internet-of-Things (NB IoT) device and enhanced Machine-Type-Communication (eMTC) devices, massive Machine-Type- Communication (mMTC) devices, (referred to herein, collectively, as IoT devices) may be designed to use a lower power level of transmission power than other types of UEs, such as smartphones, laptop computers, etc. Devices designed to use different transmission power levels may be said to pertain to different power classes, be referred to as different power class devices, etc., which may be operating in the same RAN. Since UEs attempting to initiate a

RACH procedure may do so via a shared channel (e.g. , the RACH) UEs that transmit at a lower power (e.g. , IoT devices) may tend to require more time and transmission attempts to successfully contact the RAN node. As such, a lower power UE and a higher power UE may each measure the same level of signal strength, and therefore select the same PRACH profile. However, the PRACH profile for the lower power UE may not be appropriate since the parameters of the PRACH profile (e.g. , preamble length, subframe allocations, number of UL transmission repetitions, etc.) may be provided with the assumption of the UE transmitting at a higher power level than is actually the case.

The techniques described herein may be used to ensure that uplink (UL) resources (e.g. , preamble length, transmission repetitions, subframe allocations, etc.) are properly allocated to User Equipment (UE) by incorporating the power class of the UE in the PRACH profile selection process. For example, a UE may include an offset value based on the power class of the UE. The UE may receive the offset value from the RAN node (e.g. , as part of the system information) since the RAN node may be configured to manage which PRACH resources are allocated to UEs of different power classes. Additionally, when the UE receives PRACH profiles, and the corresponding signal strength thresholds, the UE may modify the signal strength thresholds based on the offset value associated with the UE. The UE may measure a signal strength of a reference signal from the RAN node and compare the measured signal strength to the modified signal strength thresholds to determine an appropriate PRACH profile (and thus UL PRACH resources such as preamble length, number of repetitions, subframe allocations, etc.) for initiating a RACH procedure with the RAN node. Upon selecting a PRACH profile, the UE may engage in a RACH procedure with the RAN node. In some embodiments, instead of modifying the PRACH thresholds, the UE may modify the measured signal strength based on the offset value and select a PRACH profile by comparing the modified signal strength to the PRACH thresholds. In either scenario, PRACH UL resources may be allocated to the UE based on the power class of the UE.

Additionally, some of the techniques described may include an additional or alternative approach to ensuring that UL resources are allocated to UEs in accordance with the power class of UEs. For example, the RAN node may provide with an index (e.g. , lookup table) that associates PRACH resources (e.g., preamble length, number of repetitions, subframe allocations and periodicity, etc.) to different UE power classes. In such a scenario, lower power UEs (e.g. , UEs with the lowest maximum transmission power) may be allocated fewer PRACH resources than higher power UEs. In some embodiments, the RAN node may provide such information (e.g. , the index) via higher layer signaling, which may include the system information (e.g.,

System Information Blocks (SIBs) described by the 3 GPP Communication Standard). Further, the techniques described herein may be implemented during a cell selection procedure and/or in accordance with cell selection criterion of the 3 GPP Communication Standard.

Fig. 1 is a diagram conceptually illustrating an example architecture relating to 5G NR functionality. The architecture of Fig. 1 may particularly be useful for a 5 G NR transmitter that transmit at frequencies greater than 6 GHz. The components shown in Fig. 1 may be included in User Equipment (UE) 100. UE 100 may be, for example, a cellular phone (e.g., a smartphone), a Machine-to-Machine (M2M) device, an Internet of Things (IoT) device, a Narrowband IoT (NB-IoT) device, a wearable device, or any other type of communication device designed to include a 5G NR. Because the techniques described herein relate to a testing framework for UE 100, UE 100 may alternatively be referred to herein as the Device Under Test (DUT).

As shown in Fig. 1, the 5G NR functionality of UE 100 may include baseband processing circuitry 110, intermediate frequency processing circuitry 120, radio frequency processing circuitry 130, antenna array matching network 140, and antenna array 150. Baseband processing circuitry 110 may include a device (e.g., a semiconductor chip) that manages radio functions of UE 100. Baseband processing circuitry 1 10 is described in more detail below with reference to Figs. 11 and 12. Baseband processing circuitry 1 10 may include, for example, a real-time operating system (RTOS) that may control timing-dependent radio functions such as signal modulation, encoding, and frequency shifting.

Intermediate frequency processing circuit 120 may perform processing at frequencies between the baseband signal and the final carrier wave frequency. Intermediate frequency processing may include, for example, amplification or other processes. In some

implementations, intermediate frequency processing circuit 120 may be omitted or the functionality of intermediate frequency processing circuit 120 may be integrated within baseband processing circuitry 110 or radio frequency processing circuitry 130.

Radio frequency processing circuitry 130 may include the components of UE 100 that process the incoming/outgoing radio frequency signals. Radio frequency processing circuitry 130 may include, for example, RF filters, RD amplifiers, oscillators, mixers, or other radio frequency components.

Antenna array matching network 140 may include circuitry to operate as an antenna tuner to, for example, improve power transfer between antenna array 150 and radio frequency processing circuitry 130 by matching the impedance. Antenna array 150 may include two or more antennas that can be controlled to operate as a single antenna. The individual antenna elements may be coupled to radio frequency processing circuitry 130 and antenna array matching network 140 by a number of feedlines. The antenna array matching network may also include amplitude and phase control of each feedline, thereby implementing beam forming of the transmitted and received signals.

Fig. 1 illustrates an architecture of a system 100 of a network in accordance with some embodiments. The system 100 is shown to include UE 101 and a UE 102. The UEs 101 and 102 are illustrated as smartphones (e.g., handheld touchscreen mobile computing devices connectable to one or more cellular networks), but may also comprise any mobile or non-mobile computing device, such as Personal Data Assistants (PDAs), pagers, laptop computers, desktop computers, wireless handsets, or any computing device including a wireless communications interface.

In some embodiments, any of the UEs 101 and 102 can comprise an Internet of Things (IoT) UE, which can comprise a network access layer designed for low-power IoT applications utilizing short-lived UE connections. An IoT UE can utilize technologies such as machine-to- machine (M2M) or machine-type communications (MTC) for exchanging data with an MTC server or device via a public land mobile network (PLMN), Proximity-Based Service (ProSe) or device-to-device (D2D) communication, sensor networks, or IoT networks. The M2M or MTC exchange of data may be a machine-initiated exchange of data. An IoT network describes interconnecting IoT UEs, which may include uniquely identifiable embedded computing devices (within the Internet infrastructure), with short-lived connections. The IoT UEs may execute background applications (e.g., keep-alive messages, status updates, etc.) to facilitate the connections of the IoT network.

The UEs 101 and 102 may be configured to connect, e.g., communicatively couple, with a radio access network (RAN) 110— the RAN 110 may be, for example, an Evolved Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access Network (E-UTRAN), a NextGen RAN (NG RAN), or some other type of RAN. The UEs 101 and 102 utilize connections 103 and 104, respectively, each of which comprises a physical communications interface or layer (discussed in further detail below); in this example, the connections 103 and 104 are illustrated as an air interface to enable communicative coupling, and can be consistent with cellular communications protocols, such as a Global System for Mobile Communications (GSM) protocol, a code-division multiple access (CDMA) network protocol, a Push-to-Talk (PTT) protocol, a PTT over Cellular (POC) protocol, a Universal Mobile Telecommunications System (UMTS) protocol, a 3GPP Long Term Evolution (LTE) protocol, a fifth generation (5G) protocol, a New Radio (NR) protocol, and the like.

In this embodiment, the UEs 101 and 102 may further directly exchange communication data via a ProSe interface 105. The ProSe interface 105 may alternatively be referred to as a sidelink interface comprising one or more logical channels, including but not limited to a Physical Sidelink Control Channel (PSCCH), a Physical Sidelink Shared Channel (PSSCH), a Physical Sidelink Discovery Channel (PSDCH), and a Physical Sidelink Broadcast Channel (PSBCH).

The UE 102 is shown to be configured to access an access point (AP) 106 via connection 107. The connection 107 can comprise a local wireless connection, such as a connection consistent with any IEEE 802.11 protocol, wherein the AP 106 would comprise a wireless fidelity (Wi-Fi®) router. In this example, the AP 106 is shown to be connected to the Internet without connecting to the core network of the wireless system (described in further detail below).

The RAN 110 can include one or more access nodes that enable the connections 103 and 104. These access nodes (ANs) can be referred to as base stations (BSs), NodeBs, eNBs, next Generation NodeBs (gNB), RAN nodes, and so forth, and can comprise ground stations (e.g., terrestrial access points) or satellite stations providing coverage within a geographic area (e.g., a cell). The RAN 110 may include one or more RAN nodes for providing macrocells, e.g., macro RAN node 111 (referred to individually as "RAN node 111 " and collectively as "RAN nodes 111 "), and one or more RAN nodes for providing femtocells or picocells (e.g., cells having smaller coverage areas, smaller user capacity, or higher bandwidth compared to macrocells), e.g., low power (LP) RAN node 112 (referred to individually as "RAN node 112" and collectively as "RAN nodes 112").

Any of the RAN nodes 111 and 112 can terminate the air interface protocol and can be the first point of contact for the UEs 101 and 102. In some embodiments, any of the RAN nodes 111 and 112 can fulfill various logical functions for the RAN 110 including, but not limited to, radio network controller (RNC) functions such as radio bearer management, uplink and downlink dynamic radio resource management and data packet scheduling, and mobility management.

In accordance with some embodiments, the UEs 101 and 102 can be configured to communicate using Orthogonal Frequency-Division Multiplexing (OFDM) communication signals with each other or with any of the RAN nodes 111 and 112 over a multicarrier communication channel in accordance various communication techniques, such as, but not limited to, an Orthogonal Frequency-Division Multiple Access (OFDMA) communication technique (e.g., for downlink communications) or a Single Carrier Frequency Division Multiple Access (SC-FDMA) communication technique (e.g., for uplink and ProSe or sidelink communications), although the scope of the embodiments is not limited in this respect. The OFDM signals can comprise a plurality of orthogonal subcarriers.

In some embodiments, a downlink resource grid can be used for downlink transmissions from any of the RAN nodes 111 and 112 to the UEs 101 and 102, while uplink transmissions can utilize similar techniques. The grid can be a time-frequency grid, called a resource grid or time-frequency resource grid, which is the physical resource in the downlink in each slot. Such a time-frequency plane representation is a common practice for OFDM systems, which makes it intuitive for radio resource allocation. Each column and each row of the resource grid corresponds to one OFDM symbol and one OFDM subcarrier, respectively. The duration of the resource grid in the time domain corresponds to one slot in a radio frame. The smallest time- frequency unit in a resource grid is denoted as a resource element. Each resource grid comprises a number of resource blocks, which describe the mapping of certain physical channels to resource elements. Each resource block comprises a collection of resource elements; in the frequency domain, this may represent the smallest quantity of resources that currently can be allocated. There are several different physical downlink channels that are conveyed using such resource blocks.

The physical downlink shared channel (PDSCH) may carry user data and higher-layer signaling to the UEs 101 and 102. The physical downlink control channel (PDCCH) may carry information about the transport format and resource allocations related to the PDSCH channel, among other things. It may also inform the UEs 101 and 102 about the transport format, resource allocation, and H-ARQ (Hybrid Automatic Repeat Request) information related to the uplink shared channel. Typically, downlink scheduling (assigning control and shared channel resource blocks to the UE 102 within a cell) may be performed at any of the RAN nodes 111 and 112 based on channel quality information fed back from any of the UEs 101 and 102. The downlink resource assignment information may be sent on the PDCCH used for (e.g., assigned to) each of the UEs 101 and 102.

The PDCCH may use control channel elements (CCEs) to convey the control information. Before being mapped to resource elements, the PDCCH complex- valued symbols may first be organized into quadruplets, which may then be permuted using a sub-block interleaver for rate matching. Each PDCCH may be transmitted using one or more of these CCEs, where each CCE may correspond to nine sets of four physical resource elements known as resource element groups (REGs). Four Quadrature Phase Shift Keying (QPSK) symbols may be mapped to each REG. The PDCCH can be transmitted using one or more CCEs, depending on the size of the downlink control information (DCI) and the channel condition. There can be four or more different PDCCH formats defined in LTE with different numbers of CCEs (e.g., aggregation level, L=l , 2, 4, or 8).

Some embodiments may use concepts for resource allocation for control channel information that are an extension of the above-described concepts. For example, some embodiments may utilize an enhanced physical downlink control channel (EPDCCH) that uses PDSCH resources for control information transmission. The EPDCCH may be transmitted using one or more enhanced the control channel elements (ECCEs). Similar to above, each ECCE may correspond to nine sets of four physical resource elements known as an enhanced resource element groups (EREGs). An ECCE may have other numbers of EREGs in some situations.

The RAN 110 is shown to be communicatively coupled to a core network (CN) 120— via an SI interface 113. In embodiments, the CN 120 may be an evolved packet core (EPC) network, a NextGen Packet Core (NPC) network, or some other type of CN. In this embodiment, the SI interface 113 is split into two parts: the Sl-U interface 114, which carries traffic data between the RAN nodes 111 and 112 and the serving gateway (S-GW) 122, and the SI -mobility management entity (MME) interface 1 15, which is a signaling interface between the RAN nodes 111 and 112 and MMEs 121.

In this embodiment, the CN 120 comprises the MMEs 121, the S-GW 122, the Packet Data Network (PDN) Gateway (P-GW) 123, and a home subscriber server (HSS) 124. The MMEs 121 may be similar in function to the control plane of legacy Serving General Packet

Radio Service (GPRS) Support Nodes (SGSN). The MMEs 121 may manage mobility aspects in access such as gateway selection and tracking area list management. The HSS 124 may comprise a database for network users, including subscription-related information to support the network entities' handling of communication sessions. The CN 120 may comprise one or several HSSs 124, depending on the number of mobile subscribers, on the capacity of the equipment, on the organization of the network, etc. For example, the HSS 124 can provide support for routing/roaming, authentication, authorization, naming/ad dressing resolution, location dependencies, etc.

The S-GW 122 may terminate the SI interface 113 towards the RAN 110, and routes data packets between the RAN 110 and the CN 120. In addition, the S-GW 122 may be a local mobility anchor point for inter-RAN node handovers and also may provide an anchor for inter- 3 GPP mobility. Other responsibilities may include lawful intercept, charging, and some policy enforcement.

The P-GW 123 may terminate an SGi interface toward a PDN. The P-GW 123 may route data packets between the EPC network 123 and external networks such as a network including the application server 130 (alternatively referred to as application function (AF)) via an Internet Protocol (IP) interface 125. Generally, the application server 130 may be an element offering applications that use IP bearer resources with the core network (e.g., UMTS Packet Services (PS) domain, LTE PS data services, etc.). In this embodiment, the P-GW 123 is shown to be communicatively coupled to an application server 130 via an IP communications interface 125. The application server 130 can also be configured to support one or more communication services (e.g., Voice-over-Internet Protocol (VoIP) sessions, PTT sessions, group

communication sessions, social networking services, etc.) for the UEs 101 and 102 via the CN 120.

The P-GW 123 may further be a node for policy enforcement and charging data collection. Policy and Charging Enforcement Function (PCRF) 126 is the policy and charging control element of the CN 120. In a non-roaming scenario, there may be a single PCRF in the Home Public Land Mobile Network (HPLMN) associated with a UE's Internet Protocol Connectivity Access Network (IP-CAN) session. In a roaming scenario with local breakout of traffic, there may be two PCRFs associated with a UE's IP-CAN session: a Home PCRF (H- PCRF) within a HPLMN and a Visited PCRF (V-PCRF) within a Visited Public Land Mobile Network (VPLMN). The PCRF 126 may be communicatively coupled to the application server 130 via the P-GW 123. The application server 130 may signal the PCRF 126 to indicate a new service flow and select the appropriate Quality of Service (QoS) and charging parameters. The PCRF 126 may provision this rule into a Policy and Charging Enforcement Function (PCEF) (not shown) with the appropriate traffic flow template (TFT) and QoS class of identifier (QCI), which commences the QoS and charging as specified by the application server 130. The quantity of devices and/or networks, illustrated in Fig. 1, is provided for explanatory purposes only. In practice, system 100 may include additional devices and/or networks; fewer devices and/or networks; different devices and/or networks; or differently arranged devices and/or networks than illustrated in Fig. 1. For example, while not shown, environment 100 may include devices that facilitate or enable communication between various components shown in environment 100, such as routers, modems, gateways, switches, hubs, etc. Alternatively, or additionally, one or more of the devices of system 100 may perform one or more functions described as being performed by another one or more of the devices of system 100.

Additionally, the devices of system 100 may interconnect with each other and/or other devices via wired connections, wireless connections, or a combination of wired and wireless connections. In some embodiments, one or more devices of system 100 may be physically integrated in, and/or may be physically attached to, one or more other devices of system 100. Also, while "direct" connections may be shown between certain devices in Fig. 1, some of said devices may, in practice, communicate with each other via one or more additional devices and/ or networks .

Fig. 2 is a flow chart illustrating an example process 200 for allocating PRACH UL resources based on a UE power class. Process 200 may be performed by, for example, UE 101.

As shown, process 200 may include determining a signal strength of a reference signal from RAN node 110 (block 210). For example, UE 101 may detect an RSRP signal from RAN node 110 and may measure or estimate a level of signal strength of the RSRP signal. This may be part of a procedure referred to as determining the PRACH enhanced coverage (CE) level of UE 101. Additionally, or alternatively, UE 101 may determine the signal strength of the reference signal in response to initially powering on, during a connection procedure with the RAN node 110, while transitioning from an idle state to a connected state, or during a handover procedure.

Process 200 may also include determining a power class of UE 101. For example, UE

101 may correspond to a particular UE power class, which may correspond to a maximum transmission power level of UE 101. A NB IoT device or eMTC device may correspond to a lower power class of UE, while a smartphone may correspond to a higher power class of UE. The power class may be expressed in terms of the decibel level of the transmission capacity of the UE. The power class of UE 101 may be assigned to UE 101 during an initial manufacturing process, an initial deployment process or at another time prior to performing process 200. In some embodiments, the UE power class may be assigned to UE 101 by the network, during a software update or at another time. In some embodiments, the UE power class may correspond to a UE type (e.g., a type 2 UE, NB IoT UE, eMTC UE, etc.) and/or UE category (e.g. , category ΜΙ , ΝΒΙ, etc.).

Process 200 may include determining an offset value associated with the power class of UE 101 (block 230). For example, UE 101 may receive a table, index, or another type of data structure., from RAN node 110 that associates different power classes with different offset values (also referred to as a P-compensation offset). In some embodiments, this information may be received by UE 101 as part of the system information from RAN node 110. In some embodiments, UE 101 may receive the offset value from another source and/or at another time, such as during initial manufacture of UE 101.

Process 200 may include modifying signal strength thresholds for PRACH profiles based on the offset value (block 240). As described above, the system information received from RAN node 110 may include PRACH profiles that are each associated with a level or threshold of signal strength. As such, UE 101 may modify each signal strength threshold based on the offset value corresponding to the power class of UE 101. For example, the offset value for a lower power UE may increase one or more of the signal strength thresholds received from RAN node 110 since the lower power UE (e.g. , an IoT device) may have be configured to transmit information at a lower power level that a higher power UE (e.g. , a smartphone).

Process 200 may include determining PRACH UL resources based on the measured signal strength and the modified signal strength thresholds (block 250). After having modified the signal strength thresholds received from RAN with the offset value associated with the power class of UE 101 , UE 101 may compare the strength of the reference signal (e.g. , the RSRP signal) from RAN node 110 with the modified signal strength thresholds and thereby determine which PRACH profile is appropriate for UE 101. As described above, the PRACH profile may include parameters defining UL resources, of the PRACH, that UE 101 may use to communicate with RAN node 110, such as number of repetitions, subframe allocations, etc.

Process 200 may include performing a RACH procedure in accordance with the determined UL resources (block 260). For example, UE 101 may proceed to initiate and participate in a RACH procedure with RAN node 101 (e.g. , by transmitting, and possibly retransmitting, a Msgl to RAN node 110) in accordance with the UL resources determined by UE 101 based on the power class of UE 101.

As Fig. 2 is directed to an example process that may be performed by UE 101 , the techniques described herein may include a complementary or corresponding process performed by RAN node 110. For example, RAN node 110 may store a table, index, or another type of data structure that associates UE power classes with offset values. RAN node 110 may include this information in system information (e.g. , SIBs) that are transmitted to UEs 101 within a coverage area of RAN node 110. Additionally, as a UE 101 of a particular power class attempts to perform a RACH procedure, RAN node 110 may engage (e.g. , receive transmission, retransmission, etc.) in accordance with the RACH profile selected by the UE.

Fig. 3 is a diagram of an example for determining UL resources by modifying RSRP thresholds based on a UE power class. Prior to initiating a RACH procedure with RAN node 110, UE 101 may receive system information (e.g., System Information Blocks (SIBs) from RAN node 110), which may include downlink (DL) RSRP thresholds (Threshold l ,

Threshold_2, etc.) corresponding to levels of signal strength that may be measured by UE 101. Each downlink DL RSRP threshold may be associated with a RACH profile (e.g. , P I, P_2, etc.). UE 101 may also receive information associating different UE power classes (e.g., PC_1, PC 2, etc.) with RSRP offset values (e.g., Offset l, Offset_2, etc.).

As shown, UE 101 may modify the RSRP thresholds based on the RSRP offset value, corresponding to the power class of UE 101, to create modified RSRP thresholds (e.g. , Threshold l - Offset l, Threshold_2 - Offset l, etc.). UE 101 may measure a level of signal strength from RAN node 110 ((or use a previously measured level of signal strength) and determine an appropriate RACH profile by comparing the measured signal strength to the modified RSRP thresholds. Selecting the RACH profile may provide UE 101 with a corresponding set of PRACH UL resources since each RACH profile may include, or be associated with, certain parameters for communicating with RAN node 110. As shown, example of such parameters may include a preamble length (e.g. , L I, L_2, etc.), a number of repetitions (e.g. , R_l, R_2, etc.), a subframe allocation (e.g. , S_l, S_2, etc.) that indicates the subframes UE 101 may be used for transmitting, and more. As such, each RACH profile may be associated with a set or group of parameters corresponding to UL PRACH resources.

Fig. 4 is a diagram of an example of a lower power class UE 101-1 and a higher power class UE 101-2 determining PRACH UL resources based on the respective power classes of the UEs 101-1 and 101 -2. As shown, UE 101-1 may include a lower power class UE with an offset value (Offset l), and UE 101-2 may include a higher power UE with a different offset value (Offset_2). In some embodiments, one of the UEs 101 (e.g. , the higher power class UE 101 -2) may not have an offset value (or may have an offset value of zero (0)), and corresponding

RACH profiles, may be suitable for the transmission power capabilities or configuration of such a UE. By contrast, the other UE 101 (e.g. , the lower power class UE 101-1) may have an offset value to enable the UE to select an appropriate set of PRACH UL resources as described below. Assume that the lower power class UE 101-1 and the higher power class UE 101-2 are each in the same (or a similar) location with respect to RAN node 110, such that each UE 101-1 and 101-2 measures the same level of signal strength (Strength_l) from RAN node 110.

Additionally, assume that each UE 101-1 and 101-2 has received system information (e.g. , System Information Blocks (SIBs)) from the RAN, indicating RACH profiles (P I, P_2, etc.) associated with different RSRP signal strength thresholds (Threshold l, Threshold_2, etc.). To determine the PRACH UL resources that each UE may use to initiate a RACH procedure with RAN node 110, each UE 101 may modify the RSRP thresholds from RAN node 110 based on the offset value associated with each UE 101.

The amount by which the offset value may modify the RSRP thresholds may be consistent with the power class and UL transmission capabilities of the UE. For example, the lower power class UE 101-1 may have a greater offset value, such that the modified RSRP thresholds for the lower power class UE 101 -1 are greater (e.g. , higher decibel levels) than the modified RSRP thresholds for the higher power class UE 101-2. Indeed, as mentioned above, in some embodiments, the higher power class UE 101-2 may have an offset value of zero (or not have an offset value at all) in which case the higher power class UE 101 -2 may skip the operation of modifying the RSRP thresholds.

Next, each UE may compare the RSRP signal strength measured by each UE 101-1 and 101-2 to the modified RSRP thresholds to determine which RACH profile is appropriate for communicating with RAN node 110. Each UE 101 - 1 and 101 -2 may then use the PRACH UL resources associated with the selected RACH profiles to initiate and perform a RACH procedure involving RAN node 110. As such, even though the UEs 101 each measured the same (or similar) level of RSRP signal strength, each UE 101 may use different PRACH UL resources due to the power class of each UE 101.

Embodiments described herein may be implemented into a system using any suitably configured hardware and/or software. Fig. 5 illustrates example components of a device 500 in accordance with some embodiments. In some embodiments, the device 500 may include application circuitry 502, baseband circuitry 504, Radio Frequency (RF) circuitry 506, front-end module (FEM) circuitry 508, one or more antennas 510, and power management circuitry (PMC) 512 coupled together at least as shown. The components of the illustrated device 500 may be included in a UE or a RAN node. In some embodiments, the device 500 may include less elements (e.g., a RAN node may not utilize application circuitry 502, and instead include a processor/controller to process IP data received from an EPC). In some embodiments, the device 500 may include additional elements such as, for example, memory/storage, display, camera, sensor, or input/output (I/O) interface. In other embodiments, the components described below may be included in more than one device (e.g., said circuitries may be separately included in more than one device for Cloud-RAN (C-RAN) implementations).

The application circuitry 502 may include one or more application processors. For example, the application circuitry 502 may include circuitry such as, but not limited to, one or more single-core or multi-core processors. The processor(s) may include any combination of general-purpose processors and dedicated processors (e.g., graphics processors, application processors, etc.). The processors may be coupled with or may include memory/storage and may be configured to execute instructions stored in the memory/storage to enable various applications or operating systems to run on the device 500. In some embodiments, processors of application circuitry 502 may process IP data packets received from an EPC.

The baseband circuitry 504 may include circuitry such as, but not limited to, one or more single-core or multi-core processors. The baseband circuitry 504 may include one or more baseband processors or control logic to process baseband signals received from a receive signal path of the RF circuitry 506 and to generate baseband signals for a transmit signal path of the RF circuitry 506. Baseband processing circuity 504 may interface with the application circuitry 502 for generation and processing of the baseband signals and for controlling operations of the RF circuitry 506. For example, in some embodiments, the baseband circuitry 504 may include a third generation (3G) baseband processor 504 A, a fourth generation (4G) baseband processor 504B, a fifth generation (5G) baseband processor 504C, or other baseband processor(s) 504D for other existing generations, generations in development or to be developed in the future (e.g., second generation (2G), sixth generation (6G), etc.). The baseband circuitry 504 (e.g., one or more of baseband processors 504 A-D) may handle various radio control functions that enable communication with one or more radio networks via the RF circuitry 506. In other

embodiments, some or all of the functionality of baseband processors 504 A-D may be included in modules stored in the memory 504G and executed via a Central Processing Unit (CPU) 504E. The radio control functions may include, but are not limited to, signal modulation/demodulation, encoding/decoding, radio frequency shifting, etc. In some embodiments,

modulation/demodulation circuitry of the baseband circuitry 504 may include Fast-Fourier Transform (FFT), precoding, or constellation mapping/demapping functionality. In some embodiments, encoding/decoding circuitry of the baseband circuitry 504 may include convolution, tail-biting convolution, turbo, Viterbi, or Low-Density Parity Check (LDPC) encoder/decoder functionality. Embodiments of modulation/demodulation and encoder/decoder functionality are not limited to these examples and may include other suitable functionality in other embodiments.

In some embodiments, the baseband circuitry 504 may include one or more audio digital signal processor(s) (DSP) 504F. The audio DSP(s) 504F may be include elements for compression/decompression and echo cancellation and may include other suitable processing elements in other embodiments. Components of the baseband circuitry may be suitably combined in a single chip, a single chipset, or disposed on a same circuit board in some embodiments. In some embodiments, some or all of the constituent components of the baseband circuitry 504 and the application circuitry 502 may be implemented together such as, for example, on a system on a chip (SOC).

In some embodiments, the baseband circuitry 504 may provide for communication compatible with one or more radio technologies. For example, in some embodiments, the baseband circuitry 504 may support communication with an evolved universal terrestrial radio access network (EUTRAN) or other wireless metropolitan area networks (WMAN), a wireless local area network (WLAN), a wireless personal area network (WPAN). Embodiments in which the baseband circuitry 504 is configured to support radio communications of more than one wireless protocol may be referred to as multi-mode baseband circuitry.

RF circuitry 506 may enable communication with wireless networks using modulated electromagnetic radiation through a non-solid medium. In various embodiments, the RF circuitry 506 may include switches, filters, amplifiers, etc. to facilitate the communication with the wireless network. RF circuitry 506 may include a receive signal path which may include circuitry to down-convert RF signals received from the FEM circuitry 508 and provide baseband signals to the baseband circuitry 504. RF circuitry 506 may also include a transmit signal path which may include circuitry to up-convert baseband signals provided by the baseband circuitry 504 and provide RF output signals to the FEM circuitry 508 for transmission.

In some embodiments, the receive signal path of the RF circuitry 506 may include mixer circuitry 506a, amplifier circuitry 506b and filter circuitry 506c. In some embodiments, the transmit signal path of the RF circuitry 506 may include filter circuitry 506c and mixer circuitry 506a. RF circuitry 506 may also include synthesizer circuitry 506d for synthesizing a frequency for use by the mixer circuitry 506a of the receive signal path and the transmit signal path. In some embodiments, the mixer circuitry 506a of the receive signal path may be configured to down-convert RF signals received from the FEM circuitry 508 based on the synthesized frequency provided by synthesizer circuitry 506d. The amplifier circuitry 506b may be configured to amplify the down-converted signals and the filter circuitry 506c may be a low- pass filter (LPF) or band-pass filter (BPF) configured to remove unwanted signals from the down-converted signals to generate output baseband signals. Output baseband signals may be provided to the baseband circuitry 504 for further processing. In some embodiments, the output baseband signals may be zero-frequency baseband signals, although this is not a requirement. In some embodiments, mixer circuitry 506a of the receive signal path may comprise passive mixers, although the scope of the embodiments is not limited in this respect.

In some embodiments, the mixer circuitry 506a of the transmit signal path may be configured to up-convert input baseband signals based on the synthesized frequency provided by the synthesizer circuitry 506d to generate RF output signals for the FEM circuitry 508. The baseband signals may be provided by the baseband circuitry 504 and may be filtered by filter circuitry 506c.

In some embodiments, the mixer circuitry 506a of the receive signal path and the mixer circuitry 506a of the transmit signal path may include two or more mixers and may be arranged for quadrature downconversion and upconversion, respectively. In some embodiments, the mixer circuitry 506a of the receive signal path and the mixer circuitry 506a of the transmit signal path may include two or more mixers and may be arranged for image rejection (e.g. , Hartley image rejection). In some embodiments, the mixer circuitry 506a of the receive signal path and the mixer circuitry 506a may be arranged for direct downconversion and direct upconversion, respectively. In some embodiments, the mixer circuitry 506a of the receive signal path and the mixer circuitry 506a of the transmit signal path may be configured for super-heterodyne operation.

In some embodiments, the output baseband signals and the input baseband signals may be analog baseband signals, although the scope of the embodiments is not limited in this respect. In some alternate embodiments, the output baseband signals and the input baseband signals may be digital baseband signals. In these alternate embodiments, the RF circuitry 506 may include analog-to-digital converter (ADC) and digital-to-analog converter (DAC) circuitry and the baseband circuitry 504 may include a digital baseband interface to communicate with the RF circuitry 506.

In some dual-mode embodiments, a separate radio IC circuitry may be provided for processing signals for each spectrum, although the scope of the embodiments is not limited in this respect.

In some embodiments, the synthesizer circuitry 506d may be a fractional -N synthesizer or a fractional N/N+ l synthesizer, although the scope of the embodiments is not limited in this respect as other types of frequency synthesizers may be suitable. For example, synthesizer circuitry 506d may be a delta-sigma synthesizer, a frequency multiplier, or a synthesizer comprising a phase-locked loop with a frequency divider.

The synthesizer circuitry 506d may be configured to synthesize an output frequency for use by the mixer circuitry 506a of the RF circuitry 506 based on a frequency input and a divider control input. In some embodiments, the synthesizer circuitry 506d may be a fractional N/N+l synthesizer.

In some embodiments, frequency input may be provided by a voltage controlled oscillator (VCO), although that is not a requirement. Divider control input may be provided by either the baseband circuitry 504 or the applications processor 502 depending on the desired output frequency. In some embodiments, a divider control input (e.g., N) may be determined from a look-up table based on a channel indicated by the applications processor 502.

Synthesizer circuitry 506d of the RF circuitry 506 may include a divider, a delay-locked loop (DLL), a multiplexer and a phase accumulator. In some embodiments, the divider may be a dual modulus divider (DMD) and the phase accumulator may be a digital phase accumulator (DP A). In some embodiments, the DMD may be configured to divide the input signal by either N or N+l (e.g., based on a carry out) to provide a fractional division ratio. In some example embodiments, the DLL may include a set of cascaded, tunable, delay elements, a phase detector, a charge pump and a D-type flip-flop. In these embodiments, the delay elements may be configured to break a VCO period up into Nd equal packets of phase, where Nd is the number of delay elements in the delay line. In this way, the DLL provides negative feedback to help ensure that the total delay through the delay line is one VCO cycle.

In some embodiments, synthesizer circuitry 506d may be configured to generate a carrier frequency as the output frequency, while in other embodiments, the output frequency may be a multiple of the carrier frequency (e.g., twice the carrier frequency, four times the carrier frequency) and used in conjunction with quadrature generator and divider circuitry to generate multiple signals at the carrier frequency with multiple different phases with respect to each other. In some embodiments, the output frequency may be a LO frequency (fLO). In some embodiments, the RF circuitry 506 may include an IQ/polar converter.

FEM circuitry 508 may include a receive signal path which may include circuitry configured to operate on RF signals received from one or more antennas 510, amplify the received signals and provide the amplified versions of the received signals to the RF circuitry 506 for further processing. FEM circuitry 508 may also include a transmit signal path which may include circuitry configured to amplify signals for transmission provided by the RF circuitry 506 for transmission by one or more of the one or more antennas 510. In various embodiments, the amplification through the transmit or receive signal paths may be done solely in the RF circuitry 506, solely in the FEM 508, or in both the RF circuitry 506 and the FEM 508.

In some embodiments, the FEM circuitry 508 may include a TX/RX switch to switch between transmit mode and receive mode operation. The FEM circuitry may include a receive signal path and a transmit signal path. The receive signal path of the FEM circuitry may include an LNA to amplify received RF signals and provide the amplified received RF signals as an output (e.g., to the RF circuitry 506). The transmit signal path of the FEM circuitry 508 may include a power amplifier (PA) to amplify input RF signals (e.g., provided by RF circuitry 506), and one or more filters to generate RF signals for subsequent transmission (e.g., by one or more of the one or more antennas 510).

In some embodiments, the PMC 512 may manage power provided to the baseband circuitry 504. In particular, the PMC 512 may control power-source selection, voltage scaling, battery charging, or DC-to-DC conversion. The PMC 512 may often be included when the device 500 is capable of being powered by a battery, for example, when the device is included in a UE. The PMC 512 may increase the power conversion efficiency while providing desirable implementation size and heat dissipation characteristics.

While Fig. 5 shows the PMC 512 coupled only with the baseband circuitry 504.

However, in other embodiments, the PMC 512 may be additionally or alternatively coupled with, and perform similar power management operations for, other components such as, but not limited to, application circuitry 502, RF circuitry 506, or FEM 508.

In some embodiments, the PMC 512 may control, or otherwise be part of, various power saving mechanisms of the device 500. For example, if the device 500 is in an RRC_Connected state, where it is still connected to the RAN node as it expects to receive traffic shortly, then it may enter a state known as Discontinuous Reception Mode (DRX) after a period of inactivity. During this state, the device 500 may power down for brief intervals of time and thus save power.

If there is no data traffic activity for an extended period of time, then the device 500 may transition off to an RRC Idle state, where it disconnects from the network and does not perform operations such as channel quality feedback, handover, etc. The device 500 goes into a very low power state and it performs paging where again it periodically wakes up to listen to the network and then powers down again. The device 500 may not receive data in this state, in order to receive data, it must transition back to RRC Connected state.

An additional power saving mode may allow a device to be unavailable to the network for periods longer than a paging interval (ranging from seconds to a few hours). During this time, the device is totally unreachable to the network and may power down completely. Any data sent during this time incurs a large delay and it is assumed the delay is acceptable.

Processors of the application circuitry 502 and processors of the baseband circuitry 504 may be used to execute elements of one or more instances of a protocol stack. For example, processors of the baseband circuitry 504, alone or in combination, may be used execute Layer 3, Layer 2, or Layer 1 functionality, while processors of the application circuitry 504 may utilize data (e.g., packet data) received from these layers and further execute Layer 4 functionality (e.g., transmission communication protocol (TCP) and user datagram protocol (UDP) layers). As referred to herein, Layer 3 may comprise a radio resource control (RRC) layer, described in further detail below. As referred to herein, Layer 2 may comprise a medium access control

(MAC) layer, a radio link control (RLC) layer, and a packet data convergence protocol (PDCP) layer, described in further detail below. As referred to herein, Layer 1 may comprise a physical (PHY) layer of a UE/RAN node, described in further detail below.

Fig. 6 illustrates example interfaces of baseband circuitry in accordance with some embodiments. As discussed above, the baseband circuitry 504 of Fig. 5 may comprise processors 504A-504E and a memory 504G utilized by said processors. Each of the processors 504A-504E may include a memory interface, 604A-604E, respectively, to send/receive data to/from the memory 604G.

The baseband circuitry 604 may further include one or more interfaces to

communicatively couple to other circuitries/devices, such as a memory interface 612 (e.g., an interface to send/receive data to/from memory external to the baseband circuitry 504), an application circuitry interface 614 (e.g., an interface to send/receive data to/from the application circuitry 502 of Fig. 5), an RF circuitry interface 616 (e.g., an interface to send/receive data to/from RF circuitry 506 of Fig. 5), a wireless hardware connectivity interface 616 (e.g., an interface to send/receive data to/from Near Field Communication (NFC) components,

Bluetooth® components (e.g., Bluetooth® Low Energy), Wi-Fi® components, and other communication components), and a power management interface 620 (e.g., an interface to send/receive power or control signals to/from the PMC 512).

Fig. 7 is a block diagram illustrating components, according to some example embodiments, able to read instructions from a machine-readable or computer-readable medium

(e.g., a non-transitory machine-readable storage medium) and perform any one or more of the methodologies discussed herein. Specifically, Fig. 7 shows a diagrammatic representation of hardware resources 700 including one or more processors (or processor cores) 710, one or more memory/storage devices 720, and one or more communication resources 730, each of which may be communicatively coupled via a bus 740. For embodiments where node virtualization (e.g., NFV) is utilized, a hypervisor 702 may be executed to provide an execution environment for one or more network slices/sub-slices to utilize the hardware resources 700

The processors 710 (e.g., a central processing unit (CPU), a reduced instruction set computing (RISC) processor, a complex instruction set computing (CISC) processor, a graphics processing unit (GPU), a digital signal processor (DSP) such as a baseband processor, an application specific integrated circuit (ASIC), a radio-frequency integrated circuit (RFIC), another processor, or any suitable combination thereof) may include, for example, a processor 712 and a processor 714.

The memory/storage devices 720 may include main memory, disk storage, or any suitable combination thereof. The memory/storage devices 720 may include, but are not limited to any type of volatile or non-volatile memory such as dynamic random-access memory (DRAM), static random-access memory (SRAM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), Flash memory, solid-state storage, etc.

The communication resources 730 may include interconnection or network interface components or other suitable devices to communicate with one or more peripheral devices 704 or one or more databases 706 via a network 708. For example, the communication resources 730 may include wired communication components (e.g., for coupling via a Universal Serial Bus (USB)), cellular communication components, NFC components, Bluetooth® components (e.g., Bluetooth® Low Energy), Wi-Fi® components, and other communication components.

Instructions 750 may comprise software, a program, an application, an applet, an app, or other executable code for causing at least any of the processors 710 to perform any one or more of the methodologies discussed herein. The instructions 750 may reside, completely or partially, within at least one of the processors 710 (e.g., within the processor's cache memory), the memory/storage devices 720, or any suitable combination thereof. Furthermore, any portion of the instructions 750 may be transferred to the hardware resources 700 from any combination of the peripheral devices 704 or the databases 706. Accordingly, the memory of processors 710, the memory/storage devices 720, the peripheral devices 704, and the databases 706 are examples of computer-readable and machine-readable media.

A number of examples, relating to embodiments of the techniques described above, will next be given.

In a first example, an apparatus of a UE may comprise: an interface to radio frequency

(RF) circuitry; and one or more processors to: determine, via the interface to the RF circuitry, a signal strength corresponding to a Radio Access Network (RAN) node; receive, via the interface to the RF circuitry, a plurality of Random Access Channel (RACH) profiles of the RAN node, each RACH profile, of the plurality of RACH profiles, being associated with a signal strength threshold and including uplink (UL) resources for communicating with the RAN node;

determine an offset value based on a power class of the UE; modify the signal strength threshold of each RACH profile of the plurality of RACH profiles based on the offset value; and select a RACH profile, of the plurality of RACH profiles, based on a comparison of the modified signal strength threshold of each RACH profile and the signal strength.

In example 2, the subject matter of example 1, or any of the examples herein, wherein the one or more processors are further to: perform a RACH procedure, involving the RAN node, in accordance with the UL resources associated with the selected RACH profile.

In example 3, the subject matter of example 1, or any of the examples herein, wherein the UL resources include parameters for using a PRACH for performing a RACH procedure with the RAN node.

In example 4, the subject matter of example 1, or any of the examples herein, wherein the power class of the UE corresponds to a maximum transmission power of the UE.

In example 5, the subject matter of example 1, or any of the examples herein, wherein the offset value increases the signal strength threshold of each RACH profile of the plurality of RACH profiles.

In example 6, the subject matter of example 1, or any of the examples herein, wherein the UE includes a Narrowband Internet-of-Things (NB IoT) device.

In example 7, the subject matter of example 1, or any of the examples herein, wherein the UE includes an enhanced Machine-Type-Communication (eMTC) device.

In example 8, the subject matter of example 1, or any of the examples herein, wherein the RAN node includes an enhanced Node B (eNB) operating in accordance with a Fifth Generation (5G) New Radio (NR) Radio Access Technology (RAT).

In a ninth example, an apparatus of a UE may comprise: an interface to radio frequency (RF) circuitry; and one or more processors to: receive, via the interface to the RF circuitry, a plurality of sets of uplink (UL) Random Access Channel (RACH) resources, for communicating with a Radio Access Network (RAN) node; select, based on a measured signal strength corresponding to the RAN and a power class associated with the UE, a set of UL RACH resources of the plurality of sets of UL RACH resources; and initiate a RACH procedure with the RAN node in accordance with the selected set of UL RACH resources. In example 10, the subject matter of example 9, or any of the examples herein, wherein the UL resources include parameters for using a PRACH for performing a RACH procedure with the RAN node.

In example 11, the subject matter of example 9, or any of the examples herein, wherein the power class of the UE corresponds to a maximum transmission power of the UE.

In example 12, the subject matter of example 9, or any of the examples herein, wherein each set of UL RACH resources is associated with a signal strength threshold.

In a thirteenth example, a computer-readable medium containing program instructions for causing one or more processors, associated with a User Equipment (UE), to: determine a signal strength corresponding to a Radio Access Network (RAN) node; receive a plurality of Random Access Channel (RACH) profiles of the RAN node, each RACH profile, of the plurality of RACH profiles, being associated with a signal strength threshold and including uplink (UL) resources for communicating with the RAN node; determine an offset value based on a power class of the UE; modify the signal strength threshold of each RACH profile of the plurality of RACH profiles based on the offset value; and select a RACH profile, of the plurality of RACH profiles, based on a comparison of the modified signal strength threshold of each RACH profile and the signal strength.

In a fourteenth example, an apparatus of a UE may comprise: means for determining a signal strength corresponding to a Radio Access Network (RAN) node; means for receiving a plurality of Random Access Channel (RACH) profiles of the RAN node, each RACH profile, of the plurality of RACH profiles, being associated with a signal strength threshold and including uplink (UL) resources for communicating with the RAN node; means for determining an offset value based on a power class of the UE; means for modifying the signal strength threshold of each RACH profile of the plurality of RACH profiles based on the offset value; and means for selecting a RACH profile, of the plurality of RACH profiles, based on a comparison of the modified signal strength threshold of each RACH profile and the signal strength.

In example 15, the subject matter of example 14, or any of the examples herein, the apparatus further comprising: means for performing a RACH procedure, involving the RAN node, in accordance with the UL resources associated with the selected RACH profile.

In a sixteenth example, a method, performed by a UE, may comprise: determining a signal strength corresponding to a Radio Access Network (RAN) node; receiving a plurality of Random Access Channel (RACH) profiles of the RAN node, each RACH profile, of the plurality of RACH profiles, being associated with a signal strength threshold and including uplink (UL) resources for communicating with the RAN node; determining an offset value based on a power class of the UE; modifying the signal strength threshold of each RACH profile of the plurality of RACH profiles based on the offset value; and selecting a RACH profile, of the plurality of RACH profiles, based on a comparison of the modified signal strength threshold of each RACH profile and the signal strength.

In example 17, the subject matter of example 16, or any of the examples herein, the apparatus further comprising: performing a RACH procedure, involving the RAN node, in accordance with the UL resources associated with the selected RACH profile.

In the preceding specification, various embodiments have been described with reference to the accompanying drawings. It will, however, be evident that various modifications and changes may be made thereto, and additional embodiments may be implemented, without departing from the broader scope as set forth in the claims that follow. The specification and drawings are accordingly to be regarded in an illustrative rather than restrictive sense.

For example, while series of signals and/or operations have been described with regard to Figs. 2-4 the order of the signals/operations may be modified in other implementations.

Further, non-dependent signals may be performed in parallel.

It will be apparent that example aspects, as described above, may be implemented in many different forms of software, firmware, and hardware in the implementations illustrated in the figures. The actual software code or specialized control hardware used to implement these aspects should not be construed as limiting. Thus, the operation and behavior of the aspects were described without reference to the specific software code— it being understood that software and control hardware could be designed to implement the aspects based on the description herein.

Even though particular combinations of features are recited in the claims and/or disclosed in the specification, these combinations are not intended to be limiting. In fact, many of these features may be combined in ways not specifically recited in the claims and/or disclosed in the specification.

No element, act, or instruction used in the present application should be construed as critical or essential unless explicitly described as such. An instance of the use of the term "and," as used herein, does not necessarily preclude the interpretation that the phrase "and/or" was intended in that instance. Similarly, an instance of the use of the term "or," as used herein, does not necessarily preclude the interpretation that the phrase "and/or" was intended in that instance. Also, as used herein, the article "a" is intended to include one or more items, and may be used interchangeably with the phrase "one or more. " Where only one item is intended, the terms "one," "single, " "only," or similar language is used.

Claims

WHAT IS CLAIMED IS:

1. An apparatus of a User Equipment (UE), the apparatus comprising:

an interface to radio frequency (RF) circuitry; and

one or more processors to:

determine, via the interface to the RF circuitry, a signal strength corresponding to a Radio Access Network (RAN) node;

receive, via the interface to the RF circuitry, a plurality of Random Access Channel (RACH) profiles of the RAN node, each RACH profile, of the plurality of RACH profiles, being associated with a signal strength threshold and including uplink (UL) resources for communicating with the RAN node;

determine an offset value based on a power class of the UE;

modify the signal strength threshold of each RACH profile of the plurality of RACH profiles based on the offset value; and

select a RACH profile, of the plurality of RACH profiles, based on a comparison of the modified signal strength threshold of each RACH profile and the signal strength.

2. The apparatus of claim 1, wherein the one or more processors are further to:

perform a RACH procedure, involving the RAN node, in accordance with the UL resources associated with the selected RACH profile.

3. The apparatus of claim 1, wherein the UL resources include parameters for using a PRACH for performing a RACH procedure with the RAN node.

4. The apparatus of claim 1, wherein the power class of the UE corresponds to a maximum transmission power of the UE.

5. The apparatus of claim 1, wherein the offset value increases the signal strength threshold of each RACH profile of the plurality of RACH profiles.

6. The apparatus of claim 1, wherein the UE includes a Narrowband Internet-of-Things (NB IoT) device.

7. The apparatus of claim 1, wherein the UE includes an enhanced Machine-Type- Communication (eMTC) device.

8. The apparatus of claim 1, wherein the RAN node includes an enhanced Node B (eNB) operating in accordance with a Fifth Generation (5G) New Radio (NR) Radio Access

Technology (RAT).

9. An apparatus of a User Equipment (UE), the apparatus comprising:

an interface to radio frequency (RF) circuitry; and

one or more processors to:

receive, via the interface to the RF circuitry, a plurality of sets of uplink (UL) Random Access Channel (RACH) resources, for communicating with a Radio Access Network (RAN) node;

select, based on a measured signal strength corresponding to the RAN and a power class associated with the UE, a set of UL RACH resources of the plurality of sets of UL RACH resources; and

initiate a RACH procedure with the RAN node in accordance with the selected set of UL RACH resources.

10. The apparatus of claim 9, wherein the UL resources include parameters for using a PRACH for performing a RACH procedure with the RAN node.

11. The apparatus of claim 9, wherein each set of UL RACH resources is associated with a signal strength threshold.

12. The apparatus of claim 9, wherein the power class of the UE corresponds to a maximum transmission power of the UE.

13. The apparatus of claim 9, wherein the UE includes a Narrowband Internet-of-Things (NB IoT) device.

14. The apparatus of claim 9, wherein the UE includes an enhanced Machine-Type- Communication (eMTC) device.

15. The apparatus of claim 9, wherein the RAN node includes an enhanced Node B (eNB) operating in accordance with a Fifth Generation (5G) New Radio (NR) Radio Access

Technology (RAT).

16. A computer-readable medium containing program instructions for causing one or more processors, associated with a User Equipment (UE), to perform the operations of claims 1-8.

17. A method, performed by a User Equipment (UE), comprising operations of claims 1 -8.

18. An apparatus of a User Equipment (UE), the apparatus comprising:

means for determining a signal strength corresponding to a Radio Access Network (RAN) node;

means for receiving a plurality of Random Access Channel (RACH) profiles of the RAN node, each RACH profile, of the plurality of RACH profiles, being associated with a signal strength threshold and including uplink (UL) resources for communicating with the RAN node; means for determining an offset value based on a power class of the UE;

means for modifying the signal strength threshold of each RACH profile of the plurality of RACH profiles based on the offset value; and

means for selecting a RACH profile, of the plurality of RACH profiles, based on a comparison of the modified signal strength threshold of each RACH profile and the signal strength.

19. The apparatus of claim 18, further comprising:

means for performing a RACH procedure, involving the RAN node, in accordance with the UL resources associated with the selected RACH profile.

20. The apparatus of claim 18, wherein the UL resources include parameters for using a PRACH for performing a RACH procedure with the RAN node.

21. The apparatus of claim 18, wherein the power class of the UE corresponds to a maximum transmission power of the UE.

22. The apparatus of claim 18, wherein the offset value increases the signal strength threshold of each RACH profile of the plurality of RACH profiles.

23. The apparatus of claim 18, wherein the UE includes a Narrowband Internet-of-Things (NB IoT) device.