Random Access Radio Network Temporary Identifier (RA-RNTI) with Physical Random Access Channel (PRACH) repetition

Abstract

A wireless communication system and method related to random access in a wireless communication network are provided. A user equipment (UE) receives a configuration indicating a random access preamble for random access associated with a plurality of random access opportunities (ROs). The UE sends a random access preamble in one or more of the plurality of ROs. The UE determines one or more random access radio network temporary identifiers (RA‑RNTIs) for the plurality of ROs. The UE monitors a random access response (RAR) message in a RAR window associated with the plurality of ROs based on the one or more determined RA‑RNTIs.

Description

Technical Field

[0001] The present application relates to wireless communication systems, and more particularly to random access in wireless communication networks. Background Art

[0002] Wireless communication systems are widely deployed to provide various types of communication content, such as voice, video, data packet, messaging, broadcast, etc. These systems may be able to support communication with multiple users by sharing available system resources (e.g., time, frequency, and power). A wireless multiple-access communication system may include multiple base stations (BSs), each of which simultaneously supports communication for multiple communication devices, which may be otherwise referred to as user equipment (UE).

[0003] In order to meet the growing demand for extended mobile broadband connections, wireless communication technology is evolving from long-term evolution (LTE) technology to next-generation new radio (NR) technology, which may be referred to as the fifth generation (5G). For example, NR is designed to provide lower latency, higher bandwidth or higher throughput, and higher reliability than LTE. NR is designed to operate over a wide range of spectrum bandwidths, for example, from low-frequency bandwidths below about 1 GHz and medium-frequency bandwidths from about 1 GHz to about 6 GHz, to high-frequency bandwidths, such as millimeter wave (mmWave) bandwidths. NR is also designed to operate across different spectrum types from licensed spectrum to unlicensed and shared spectrum. Spectrum sharing enables operators to opportunistically aggregate spectrum to dynamically support high-bandwidth services. Spectrum sharing can extend the benefits of NR technology to operating entities that may not have access to licensed spectrum.

[0004] The UE can initiate network access by performing a random access procedure with the BS. For example, the UE can send a random access preamble using random access resources in a physical random access channel (PRACH). After sending the random access preamble, the UE can monitor the RAR identified by a random access radio network temporary identifier (RA-RNTI) in a downlink control channel (PDCCH) during a random access response (RAR) window. The RA-RNTI may depend on the time and / or frequency resource location of the random access resource (e.g., time and / or frequency resource index). In some network deployment scenarios where the transmit power spectral density (PSD) in the spectrum is restricted by rules, it may be desirable for the UE to repeatedly send a random access preamble, for example, using multiple random access resources in frequency and / or time to increase the likelihood that the BS detects the random access preamble. In addition, repeatedly sending a random access preamble can improve the coverage of random access. Summary of the invention

[0005] The following summarizes some aspects of the present disclosure to provide a basic understanding of the technology discussed. This summary is not an extensive overview of all expected features of the present disclosure, and is neither intended to identify important or key elements of all aspects of the present disclosure, nor is it intended to delineate the scope of any or all aspects of the present disclosure. Its sole purpose is to present some concepts of one or more aspects of the present disclosure in a summary form as a preface to a more detailed description presented later.

[0006] For example, in one aspect of the present disclosure, a method of wireless communication performed by a user equipment (UE) includes: receiving a configuration indicating a random access preamble for random access associated with multiple random access opportunities (ROs); sending the random access preamble in one or more of the multiple ROs; determining one or more random access radio network temporary identifiers (RA-RNTIs) for the multiple ROs; and monitoring a random access response (RAR) message in a RAR window associated with the multiple ROs based on the one or more determined RA-RNTIs.

[0007] In an additional aspect of the present disclosure, a method of wireless communication performed by a base station includes: sending a configuration indicating a random access preamble for random access associated with multiple random access opportunities (ROs); receiving the random access preamble in one or more of the multiple ROs from a user equipment (UE); determining one or more random access radio network temporary identifiers (RA-RNTIs) for the multiple ROs; and sending a random access response (RAR) message based on the one or more determined RA-RNTIs in a random access response (RAR) window associated with the multiple ROs in response to the random access preamble.

[0008] In an additional aspect of the present disclosure, a user equipment (UE) includes: a transceiver configured to receive a configuration indicating a random access preamble for random access associated with multiple random access opportunities (ROs); and send the random access preamble in one or more of the multiple ROs; and a processor configured to determine one or more random access radio network temporary identifiers (RA-RNTIs) for the multiple ROs; and monitor a random access response (RAR) message in a RAR window associated with the multiple ROs based on the one or more determined RA-RNTIs.

[0009] In additional aspects of the present disclosure, a base station (BS) includes: a transceiver configured to send a configuration indicating a random access preamble for random access associated with multiple random access opportunities (ROs); and receive the random access preamble in one or more of the multiple ROs from a user equipment (UE); and a processor configured to determine one or more random access radio network temporary identifiers (RA-RNTIs) for the multiple ROs, wherein the transceiver is further configured to send a random access response (RAR) message based on the one or more determined RA-RNTIs in a random access response (RAR) window associated with the multiple ROs in response to the random access preamble.

[0010] In an additional aspect of the present disclosure, a non-transitory computer-readable medium having program code recorded thereon, the program code comprising: code for causing a user equipment (UE) to receive a configuration indicating a random access preamble for random access associated with multiple random access opportunities (ROs); code for causing the UE to send a random access preamble in one or more of the multiple ROs; code for causing the UE to determine one or more random access radio network temporary identifiers (RA-RNTIs) for the multiple ROs; and code for causing the UE to monitor a random access response (RAR) message in a RAR window associated with the multiple ROs based on the one or more determined RA-RNTIs.

[0011] In an additional aspect of the present disclosure, a non-transitory computer-readable medium having program code recorded thereon, the program code comprising: code for causing a base station (BS) to send a configuration indicating a random access preamble for random access associated with a plurality of random access opportunities (ROs); code for causing the BS to receive random access preambles in one or more of the plurality of ROs from a user equipment (UE); code for causing the BS to determine one or more random access radio network temporary identifiers (RA-RNTIs) for the plurality of ROs; and code for causing the BS to send a RAR message based on the one or more determined RA-RNTIs in a random access response (RAR) window associated with the plurality of ROs in response to the random access preamble.

[0012] In additional aspects of the present disclosure, a user equipment (UE) includes: a component for receiving a configuration indicating a random access preamble for random access associated with multiple random access opportunities (ROs); a component for sending the random access preamble in one or more of the multiple ROs; a component for determining one or more random access radio network temporary identifiers (RA-RNTIs) for the multiple ROs; and a component for monitoring a random access response (RAR) message in a RAR window associated with the multiple ROs based on the one or more determined RA-RNTIs.

[0013] In additional aspects of the present disclosure, a base station (BS) includes: a component for sending a configuration indicating a random access preamble code for random access associated with multiple random access opportunities (ROs); a component for receiving the random access preamble code in one or more of the multiple ROs from a user equipment (UE); a component for determining one or more random access radio network temporary identifiers (RA-RNTIs) for the multiple ROs; and a component for sending a random access response (RAR) message based on the one or more determined RA-RNTIs in a random access response (RAR) window associated with the multiple ROs in response to the random access preamble code.

[0014] Other aspects, features, and embodiments of the present invention will become apparent to those of ordinary skill in the art upon reviewing the following description of specific exemplary embodiments of the present invention in conjunction with the accompanying drawings. Although features of the present invention may be discussed with respect to certain embodiments and drawings below, all embodiments of the present invention may include one or more of the advantageous features discussed herein. In other words, although one or more embodiments may be discussed as having certain advantageous features, one or more of these features may also be used according to the various embodiments of the present invention discussed herein. In a similar manner, although exemplary embodiments may be discussed below as device, system, or method embodiments, it should be understood that such exemplary embodiments may be implemented in various devices, systems, and methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 A wireless communication network in accordance with some aspects of the present disclosure is illustrated.

[0016] Figure 2 A radio frame structure in accordance with some aspects of the present disclosure is illustrated.

[0017] Figure 3A is a signaling diagram illustrating a random access method according to some aspects of the present disclosure.

[0018] Figure 3B A random access preamble transmission scheme according to some aspects of the present disclosure is illustrated.

[0019] Figure 3C A random access response (RAR) transmission scheme according to some aspects of the present disclosure is illustrated.

[0020] Figure 4 A random access preamble transmission scheme using multiple ROs according to some aspects of the present disclosure is illustrated.

[0021] Figure 5 A random access preamble transmission scheme using multiple ROs according to some aspects of the present disclosure is illustrated.

[0022] Figure 6 A random access preamble transmission scheme using multiple ROs according to some aspects of the present disclosure is illustrated.

[0023] Figure 7 A random access preamble transmission scheme using multiple ROs according to some aspects of the present disclosure is illustrated.

[0024] Fig. 8A An RAR transmission scheme for multi-RO based random access according to some aspects of the present disclosure is illustrated.

[0025] Figure 8B An RAR transmission scheme for multi-RO based random access according to some aspects of the present disclosure is illustrated.

[0026] Figure 8C An RAR transmission scheme for multi-RO based random access according to some aspects of the present disclosure is illustrated.

[0027] Fig. 9 is a flow chart of a random access method according to some aspects of the present disclosure.

[0028] Fig.10 A random access preamble transmission scheme using multiple ROs according to some aspects of the present disclosure is illustrated.

[0029] Fig.11 is a block diagram of a user equipment (UE) according to some aspects of the present disclosure.

[0030] Fig.12 is a block diagram of an exemplary base station (BS) according to some aspects of the present disclosure.

[0031] Fig.13 is a flow chart of a method of wireless communication according to some aspects of the present disclosure.

[0032] Fig.14 is a flow chart of a method of wireless communication according to some aspects of the present disclosure. DETAILED DESCRIPTION

[0033] The detailed description described below in conjunction with the accompanying drawings is intended as a description of various configurations and is not intended to represent the only configuration in which the concepts described herein can be practiced. The detailed description includes specific details for the purpose of providing a thorough understanding of the various concepts. However, it is apparent to those skilled in the art that these concepts can be practiced without these specific details. In some cases, in order to avoid confusing these concepts, well-known structures and components are shown in block diagram form.

[0034] The present disclosure generally relates to wireless communication systems, also referred to as wireless communication networks. In various embodiments, these techniques and devices can be used for wireless communication networks, such as code division multiple access (CDMA) networks, time division multiple access (TDMA) networks, frequency division multiple access (FDMA) networks, orthogonal FDMA (OFDMA) networks, single carrier FDMA (SC-FDMA) networks, LTE networks, global mobile communication systems (GSM) networks, 5th generation (5G) or new radio (NR) networks, and other communication networks. As described herein, the terms "network" and "system" can be used interchangeably.

[0035] OFDMA networks can implement radio technologies such as Evolved UTRA (E-UTRA), Institute of Electrical and Electronics Engineers (IEEE) 802.11, IEEE 802.16, IEEE 802.20, flash-OFDM, etc. UTRA, E-UTRA, and GSM are part of Universal Mobile Telecommunications System (UMTS). In particular, Long Term Evolution (LTE) is a version of UMTS that uses E-UTRA. UTRA, E-UTRA, GSM, UMTS, and LTE are described in documents provided by an organization named "3rd Generation Partnership Project" (3GPP), and cdma2000 is described in documents provided by an organization named "3rd Generation Partnership Project 2" (3GPP2). These various radio technologies and standards are known or are being developed. For example, the 3rd Generation Partnership Project (3GPP) is a collaboration between telecommunications association groups that aims to define globally applicable third generation (3G) mobile phone specifications. 3GPP Long Term Evolution (LTE) is a 3GPP project whose purpose is to improve the UMTS mobile phone standard. 3GPP may define specifications for next generation mobile networks, mobile systems, and mobile devices. The present disclosure focuses on the evolution of wireless technology from LTE, 4G, 5G, NR and beyond, where access to the wireless spectrum is shared between networks using a set of new and different radio access technologies or radio air interfaces.

[0036] In particular, 5G networks take into account diverse deployments, diverse spectrum, and diverse services and devices that can be implemented using a unified air interface based on OFDM. To achieve these goals, in addition to developing new radio technologies for 5G NR networks, further enhancements to LTE and LTE-A are also considered. 5G NR will be able to expand to provide coverage: (1) for networks with ultra-high density (e.g., ~1M nodes / km) 2 ), ultra-low complexity (e.g., ~10s of bit / sec), ultra-low energy (e.g., ~10 years+ battery life), and deep coverage to reach challenging locations; (2) including mission-critical controls with strong security to protect sensitive personal, financial, or confidential information, ultra-high reliability (e.g., ~99.9999% reliability), ultra-low latency (e.g., ~1ms), and a wide range of mobile or immobile users; and (3) with enhanced mobile broadband, including very high capacity (e.g., ~10Tbps / km 2 ), extremely high data rates (e.g., multi-Gbps rates, 100+Mbps user experience rates), and deep perception with advanced discovery and optimization.

[0037] The 5G NR communication system can be implemented to use an optimized OFDM-based waveform with scalable parameters and transmission time intervals (TTIs). Additional features may also include a general, flexible framework to effectively multiplex services and features using dynamic, low-latency time division duplex (TDD) / frequency division duplex (FDD) designs; and advanced wireless technologies such as massive multiple-input multiple-output (MIMO), robust millimeter wave (mmWave) transmission, advanced channel coding, and device-centric mobility. The scalability of parameters in 5G NR, with the extension of subcarrier spacing, can effectively address the operation of different services across different spectrums and different deployments. For example, in various outdoor and macro coverage deployments of less than 3GHz FDD / TDD implementations, the subcarrier spacing may appear at 15kHz on bandwidths (BW) such as 5, 10, 20MHz, etc. For other various outdoor and small cell coverage deployments of TDD greater than 3GHz, the subcarrier spacing may appear at 30kHz on a BW of 80 / 100MHz. For various other indoor broadband implementations, using TDD on the unlicensed portion of the 5GHz band, subcarrier spacing may occur at 60kHz on 160MHz BW. Finally, for various deployments transmitting with mmWave components on TDD at 28GHz, subcarrier spacing may occur at 120kHz on 500MHz BW.

[0038] 5G NR's scalable parameter set facilitates scalable TTI for different latency and quality of service (QoS) requirements. For example, shorter TTIs can be used for low latency and high reliability, while longer TTIs can be used for higher spectral efficiency. Efficient multiplexing of long TTIs and short TTIs to allow transmission to be started on symbol boundaries. 5G NR also considers a self-contained integrated subframe design that contains UL / downlink scheduling information, data, and acknowledgment in the same subframe. The self-contained integrated subframe supports communications in unlicensed or contention-based shared spectrum, and adaptive UL / downlink can be flexibly configured on a per-cell basis to dynamically switch between uplink and downlink to meet current business needs.

[0039] Various other aspects and features of the present disclosure are further described below. Obviously, the teachings herein can be embodied in various forms, and any specific structure, function, or both disclosed herein are only representative and non-restrictive. Based on the teachings herein, it should be understood by those of ordinary skill in the art that an aspect disclosed herein can be implemented independently of any other aspect, and two or more of these aspects can be combined in various ways. For example, any number of aspects set forth herein can be used to implement a device or practice a method. In addition, in addition to one or more of the various aspects set forth herein, or in addition to one or more of the various aspects set forth herein, other structures, functions, or structures and functions can be used to implement such a device or practice such a method. For example, a method can be implemented as a system, device, apparatus, and / or as a part of an instruction stored on a computer-readable medium for execution on a processor or computer. In addition, an aspect can include at least one element of a claim.

[0040] The deployment of NR in unlicensed spectrum is called unlicensed NR (NR-U). Some research has been done on the deployment of NR-U in the 5 GHz unlicensed band. The Federal Communications Commission (FCC) and the European Telecommunications Standards Institute (ETSI) are working to manage 6 GHz as a new unlicensed band for wireless communications. The addition of the 6 GHz band allows hundreds of megahertz (MHz) of bandwidth (BW) to be available for unlicensed band communications. In the 5 GHz band, depending on the region, the UE and / or BS can transmit with a power spectral density (PSD) of about 10 decibel milliwatts per megahertz (dBm / MHz) to about 11 dBm / MHz. For example, FCC regulations are proposing stricter PSD requirements for the 6 GHz band to protect existing devices such as video camera communications in the 6 GHz band. For example, in the 6 GHz band, the UE can transmit at a PSD of about -1 dBm / MHz, while the BS can transmit at a PSD of about 5 dBm / MHz. In NR-U Release 16, UE transmissions are specified based on a 20MHz transmission bandwidth and a transmission power of approximately 23dBm. For example, uplink interleaved waveforms are introduced for the physical uplink control channel (PUCCH), physical uplink shared channel (PUSCH), and physical random access channel (PRACH) to meet the PSD requirements in the 5GHz band. Interleaved waveform transmissions may refer to transmissions that occupy frequency interleaving, which may include a set of resource blocks (RBs) that are separated from each other by one or more other RBs in the frequency band.

[0041] Given the lower PSD requirements in the 6 GHz band (where the UE is restricted to transmit at a lower PSD of 11 dBm / MHz and the BS is restricted to transmit at a lower PSD of 5 dBm / MHz compared to the 5 GHz band), the link budget is significantly reduced. In addition, there is a mismatch of about 6 dBm / MHz between the UL PSD requirement and the DL PSD requirement, resulting in a weaker or lower link budget for the UL than for the DL. The reduced link budget and the mismatch between the UL link budget and the DL link budget may affect random access in the network. If the BS cannot detect the random access preamble from the UE, the UE may not be able to access the network. One way to achieve a similar link budget in the 6 GHz band as in the 5 GHz band is to increase the BW occupancy of the random access preamble transmission, for example by using a longer random access preamble sequence or repeating the random access preamble so that the transmission can occupy a wider frequency BW. For example, NR-U Release 16 defines a random access preamble length of 571 for a subcarrier spacing (SCS) of 30 kilohertz (kHz) and a random access preamble length of 1151 for an SCS of 15 kHz, so that the random access preamble can span a BW of approximately 20 MHz. Alternatively, the UE may send a long random access preamble in time or repeat the random access preamble in time. In any case, in order to meet the PSD requirements and achieve a specific link budget, the UE may use multiple random access opportunities (ROs) (e.g., multiple random access resources) to send a longer random access preamble or repeat the random access preamble. As discussed above, the UE may monitor the RAR after sending a random access preamble based on a random access radio network temporary identifier (RA-RNTI), which is determined based on the random access resource or RO used for random access preamble transmission. When the UE sends a random access preamble using multiple ROs, it may not be clear how the UE can calculate the RA-RNTI of the multiple ROs and / or determine the RAR window for RAR monitoring.

[0042] The present application describes a mechanism for determining (multiple) RA-RNTIs and / or RAR windows for random access using multiple ROs. For example, a BS may send a random access configuration indicating a pool of random access preambles and associated ROs that a UE can use for random access. In some instances, the BS may broadcast a system information block (SIB) including the random access configuration. The UE may select a random access preamble from the pool and select multiple ROs from the associated ROs. The UE may send a selected random access preamble in the selected multiple ROs. In some instances, the selection of the random access preamble and / or multiple ROs may be a random selection. The random access preamble may include multiple PRACH preamble sequences. In some instances, the multiple PRACH preamble sequences are different sequences associated with each other. In some instances, the multiple PRACH preamble sequences may be repetitions of the PRACH preamble sequences, which may be referred to as repeated preambles. The transmission of random access preambles using multiple ROs may be referred to as multi-RO based random access preamble transmission or multi-RO based random access. A UE that sends a random access preamble based on multiple ROs may be referred to as a UE accessing based on multiple ROs. After sending random access preambles in multiple ROs, the UE may determine one or more RA-RNTIs of the multiple ROs according to some rules, which may be predetermined or indicated by the BS, for example, in a random access configuration.

[0043] In some aspects, the UE may determine a single RA-RNTI for the multiple ROs based on a predetermined RO among the multiple ROs. Therefore, the UE may monitor the RAR from the BS based on a single RA-RNTI during the RAR window. In some other aspects, the UE may determine the RA-RNTI for each RO among the multiple ROs. In other words, there is a one-to-one correspondence between the RA-RNTI and the RO. Therefore, the UE may monitor the RAR from the BS based on multiple RA-RNTIs determined for the multiple ROs during the RAR window. The RAR window may start after the earliest RO among the multiple ROs, after the last RO among the multiple ROs, or after any RO among the multiple ROs. In some aspects, the BS may include the configuration of the RAR window in the random access configuration.

[0044] In some aspects, the BS may configure different random access preamble pools for random access based on multiple ROs and random access based on a single RO. Random access based on a single RO means that the UE sends a random access preamble in a single RO. A UE that uses a single RO for random access may be referred to as a traditional UE or a UE based on a single RO access. The BS may configure some ROs to be shared between random access based on multiple ROs and random access based on a single RO. The BS may also configure some dedicated ROs for dedicated random access based on multiple ROs. Thus, the UE may select a random access preamble from a random access preamble pool based on multiple ROs, and may select multiple ROs from a dedicated RO or a shared RO, and send random access preambles in multiple ROs. When the UE sends a random access preamble in multiple ROs selected from a dedicated RO, the UE may determine a single RA-RNTI for multiple ROs based on a predetermined RO for RAR monitoring in multiple ROs. Alternatively, when the UE sends a random access preamble in multiple ROs selected from a shared RO, the UE may determine a RA-RNTI for each RO in multiple ROs, and perform RAR monitoring based on each RA-RNTI.

[0045] In some aspects, the UE may determine a single RA-RNTI for the multiple ROs based on a function associated with the multiple ROs. For example, a new function for calculating the RA-RNTI may be defined based on the time and / or frequency position of each of the multiple ROs.

[0046] Various aspects of the present disclosure may provide several benefits. For example, the specification or indication of a rule for determining (multiple) RA-RNTIs for random access based on multiple ROs may facilitate RA-RNTI determination for random access based on multiple ROs. Using a single RA-RNTI based on a predetermined RO among multiple ROs for RAR monitoring may be simple and may utilize the current RA-RNTI calculation mechanism in 3GPP. Using multiple RA-RNTIs (with a one-to-one correspondence between RA-RNTI and RO) may also utilize the current RA-RNTI calculation mechanism in 3GPP and may enable the BS to respond to multiple UEs (e.g., UEs accessed based on multiple ROs and UEs accessed based on a single RO) by broadcasting a single RAR message (e.g., random access message 2 in a four-step random access or random access message B in a two-step random access), which will be discussed more fully herein. Using a dedicated RO for random access based on multiple ROs or a shared RO for sharing between random access based on multiple ROs and random access based on a single RO may provide flexibility in random access, and when a dedicated RO is used, the complexity of RAR monitoring at the UE and / or the flexibility of RAR response at the BS may be reduced. The use of the new function can provide further flexibility in random access of multiple ROs.

[0047] Figure 1 A wireless communication network 100 according to some embodiments of the present disclosure is illustrated. The network 100 may be a 5G network. The network 100 includes a plurality of base stations (BSs) 105 (labeled 105a, 105b, 105c, 105d, 105e, and 105f, respectively) and other network entities. The BS 105 may be a station that communicates with the UE 115 and may also be referred to as an evolved Node B (eNB), a next generation eNB (gNB), an access point, etc. Each BS 105 may provide communication coverage for a particular geographic area. In 3GPP, the term "cell" may refer to this particular geographic coverage area of ​​the BS 105 and / or a BS subsystem that serves the coverage area, depending on the context in which the term is used.

[0048] The BS 105 may provide communication coverage for macro cells or small cells (such as pico cells or femto cells) and / or other types of cells. A macro cell generally covers a relatively large geographic area (e.g., a radius of several kilometers) and may allow unrestricted access by UEs that have a service subscription with a network provider. Small cells such as pico cells will generally cover a relatively small geographic area and may allow unrestricted access by UEs that have a service subscription with a network provider. Small cells such as femto cells will generally also cover a relatively small geographic area (e.g., a home) and, in addition to unrestricted access, may also provide restricted access for UEs associated with the femto cells (e.g., UEs in a closed subscriber group (CSG) , UEs of users in a home, etc.). A BS for a macro cell may be referred to as a macro BS. A BS for a small cell may be referred to as a small cell BS, a pico BS, a femto BS, or a home BS. In Figure 1 In the example shown, BS 105d and BS 105e may be conventional macro BSs, while BS 105a-105c may be macro BSs enabled with one of three-dimensional (3D), full-dimensional (FD), or massive MIMO. BS 105a-105c may utilize its higher-dimensional MIMO performance to utilize 3D beamforming in elevation and azimuth beamforming to increase coverage and capacity. BS 105f may be a small cell BS, which may be a home node or a portable access point. BS 105 may support one or more (e.g., two, three, four, etc.) cells.

[0049] The network 100 may support synchronous or asynchronous operation. For synchronous operation, the BSs may have similar frame timing, and transmissions from different BSs may be approximately aligned in time. For asynchronous operation, the BSs may have different frame timing, and transmissions from different BSs may not be aligned in time.

[0050] UE 115 is dispersed throughout the wireless network 100, and each UE 115 can be fixed or mobile. UE 115 can also be referred to as a terminal, a mobile station, a subscriber unit, a station, etc. UE 115 can be a cellular phone, a personal digital assistant (PDA), a wireless modem, a wireless communication device, a handheld device, a tablet computer, a laptop, a cordless phone, a wireless local loop (WLL) station, etc. In one aspect, UE 115 can be a device including a universal integrated circuit card (UICC). In another aspect, UE can be a device that does not include a UICC. In some aspects, UE 115 that does not include a UICC can also be referred to as an IoT device or an Internet of Everything (IoE) device. UE 115a-115d is an example of a mobile smart phone type device that accesses the network 100. UE 115 can also be a machine specifically configured for connecting communications, including machine type communications (MTC), enhanced MTC (eMTC), narrowband IoT (NB-IoT), etc. UE 115e-115h is an example of various machines configured for communication of accessing the network 100. UE 115i-115k is an example of a vehicle equipped with a wireless communication device configured for communication accessing network 100. UE 115 is capable of communicating with any type of BS, whether macro BS, small cell, etc. Figure 1 , the lightning ball (e.g., communication link) indicates wireless transmission between UE 115 and a serving BS 105 that is designed to serve UE 115 on a downlink (DL) and / or uplink (UL), desired transmission between BSs 105, backhaul transmission between BSs, or sidelink transmission between UE 115.

[0051] In operation, BS 105a-105c may use 3D beamforming and cooperative spatial techniques such as coordinated multipoint (CoMP) or multi-connectivity to serve UEs 115a and 115b. Macro BS 105d may perform backhaul communications with BS 105a-105c and small cell BS 105f. Macro BS 105d may also send multicast services subscribed to and received by UEs 115c and 115d. Such multicast services may include mobile TV or streaming video, or may include other services for providing community information, such as weather emergencies or alerts, such as Amber alerts or gray alerts.

[0052] The BS 105 may also communicate with a core network. The core network may provide user authentication, access authorization, tracking, Internet Protocol (IP) connectivity, and other access, routing, or mobility functions. At least some of the BSs 105 (e.g., which may be examples of gNBs or access node controllers (ANCs)) may be connected to the core network via a backhaul link (e.g., NG-C, NG-U, etc.) and may perform radio configuration and scheduling for communicating with the UE 115. In various examples, the BSs 105 may communicate with each other directly or indirectly (e.g., through the core network) via a backhaul link (e.g., X1, X2, etc.), which may be a wired or wireless communication link.

[0053] The network 100 may also support mission-critical communications through ultra-reliable and redundant links for mission-critical devices, such as UE 115e, which may be a drone. The redundant communication links with UE 115e may include links from macro BSs 105d and 105e, and links from small cell BS 105f. Other machine-type devices, such as UE 115f (e.g., a thermometer), UE 115g (e.g., a smart meter), and UE 115h (e.g., a wearable device) may communicate directly with a BS (such as small cell BS 105f and macro BS 105e) through the network 100, or in a multi-step configuration by communicating with another user device to relay its information to the network, such as UE 115f transmitting temperature measurement information to smart meter UE 115g, which then reports to the network through small cell BS 105f. The network 100 can also provide additional network efficiency through dynamic, low-latency TDD / FDD communications, such as V2V, V2X, C-V2X communications between UE 115i, 115j or 115k and other UEs 115, and / or vehicle-to-infrastructure (V2I) communications between UE 115i, 115j or 115k and BS 105.

[0054] In some implementations, the network 100 communicates using an OFDM-based waveform. An OFDM-based system can divide the system BW into multiple (K) orthogonal subcarriers, which are also generally referred to as subcarriers, tones, bins, etc. Each subcarrier can be modulated with data. In some instances, the subcarrier spacing between adjacent subcarriers can be fixed, and the total number of subcarriers (K) can depend on the system BW. The system BW can also be divided into subbands. In other cases, the subcarrier spacing and / or the duration of the TTI can be scalable.

[0055] In some aspects, BS 105 may allocate or schedule transmission resources (e.g., in the form of time-frequency resource blocks (RBs)) for downlink (DL) and uplink (UL) transmissions in network 100. DL refers to the transmission direction from BS 105 to UE 115, and UL refers to the transmission direction from UE 115 to BS 105. Communication may be in the form of radio frames. A radio frame may be divided into a plurality of subframes or time slots, such as approximately 10. Each time slot may also be divided into micro-time slots. In FDD mode, simultaneous UL and DL transmissions may occur in different frequency bands. For example, each subframe includes a UL subframe in a UL frequency band and a DL subframe in a DL frequency band. In TDD mode, UL and DL transmissions occur in different time periods using the same frequency band. For example, a subset of subframes (e.g., DL subframes) in a radio frame may be used for DL ​​transmissions, and another subset of subframes (e.g., UL subframes) in a radio frame may be used for UL transmissions.

[0056] DL subframes and UL subframes may be further divided into several regions. For example, each DL or UL subframe may have a predefined region for sending reference signals, control information, and data. A reference signal is a predetermined signal that facilitates communication between BS 105 and UE 115. For example, a reference signal may have a specific pilot pattern or structure, wherein the pilot tone may span an operable BW or frequency band, each located at a predefined time and a predefined frequency. For example, BS 105 may send a cell-specific reference signal (CRS) and / or a channel state information-reference signal (CSI-RS) to enable UE 115 to estimate a DL channel. Similarly, UE 115 may send a sounding reference signal (SRS) to enable BS 105 to estimate an UL channel. Control information may include resource allocation and protocol control. Data may include protocol data and / or operable data. In some aspects, BS 105 and UE 115 may communicate using self-contained subframes. A self-contained subframe may include a portion for DL ​​communication and a portion for UL communication. A self-contained subframe may be centered on DL or centered on UL. A DL-centric subframe may include a duration for communication of the DL that is longer than a duration for communication of the UL. A UL-centric subframe may include a duration for communication of the UL that is longer than a duration for communication of the UL.

[0057] In some aspects, the network 100 may be an NR network deployed on a licensed spectrum. The BS 105 may send synchronization signals (e.g., including a primary synchronization signal (PSS) and a secondary synchronization signal (SSS)) in the network 100 to facilitate synchronization. The BS 105 may broadcast system information associated with the network 100 (e.g., including a master information block (MIB), residual system information (RMSI), and other system information (OSI)) to facilitate initial network access. In some instances, the BS 105 may broadcast the PSS, SSS, and / or MIB in the form of a synchronization signal block (SSB) on a physical broadcast channel (PBCH), and may broadcast the RMSI and / or OSI on a physical downlink shared channel (PDSCH).

[0058] In some aspects, a UE 115 attempting to access the network 100 may perform an initial cell search by detecting the PSS from the BS 105. The PSS may enable synchronization of periodic timing and may indicate a physical layer identification value. The UE 115 may then receive the SSS. The SSS may enable radio frame synchronization and may provide a cell identification value that may be combined with the physical layer identification value to identify a cell. The PSS and SSS may be located in the center portion of the carrier or at any suitable frequency within the carrier.

[0059] After receiving the PSS and SSS, the UE 115 may receive the MIB. The MIB may include system information for initial network access and scheduling information for RMSI and / or OSI. After decoding the MIB, the UE 115 may receive the RMSI and / or OSI. The RMSI and / or OSI may include radio resource control (RRC) information related to random access channel (RACH) procedures, paging, control resource sets (CORESET) for physical downlink control channel (PDCCH) monitoring, physical UL control channel (PUCCH), physical UL shared channel (PUSCH), power control, and SRS.

[0060] After obtaining the MIB, RMSI and / or OSI, the UE 115 may perform a random access procedure to establish a connection with the BS 105. In some examples, the random access procedure may be a four-step random access procedure. For example, the UE 115 may send a random access preamble and the BS 105 may respond with a RAR. The RAR may include a detected random access preamble identifier (ID) corresponding to the random access preamble, timing advance (TA) information, UL authorization, a temporary cell-radio network temporary identifier (C-RNTI), and / or a backoff indicator. Upon receiving the RAR, the UE 115 may send a connection request to the BS 105, and the BS 105 may respond with a connection response. The connection response may indicate contention resolution. In some examples, the random access preamble, the RAR, the connection request, and the connection response may be referred to as message 1 (MSG1), message 2 (MSG2), message 3 (MSG3), and message 4 (MSG4), respectively. In some examples, the random access procedure may be a two-step random access procedure, where the UE 115 may send a random access preamble and a connection request in a single transmission, and the BS 105 may respond by sending a RAR and a connection response in a single transmission. In some aspects, the UE 115 may send a random access preamble in a single random access resource or a single RO. In some aspects, the UE 115 may send a random access preamble in multiple ROs, where the random access preamble may include multiple parts, each part being sent in one of the multiple ROs, as will be discussed more fully herein.

[0061] After establishing the connection, the UE 115 and the BS 105 may enter a normal operation phase, in which operational data may be exchanged. For example, the BS 105 may schedule the UE 115 for UL and / or DL ​​communications. The BS 105 may send an UL and / or DL ​​scheduling grant to the UE 115 via the PDCCH. The scheduling grant may be sent in the form of DL control information (DCI). The BS 105 may send a DL communication signal (e.g., carrying data) to the UE 115 via the PDSCH according to the DL scheduling grant. The UE 115 may send an UL communication signal to the BS 105 via the PUSCH and / or PUCCH according to the UL scheduling grant.

[0062] In some aspects, the network 100 may operate on a system BW or a component carrier (CC) BW. The network 100 may divide the system BW into multiple BWPs (e.g., parts). The BS 105 may dynamically allocate the UE 115 to operate on a certain BWP (e.g., a certain part of the system BW). The allocated BWP may be referred to as an active BWP. The UE 115 may monitor the active BWP for signaling information from the BS 105. The BS 105 may schedule the UE 115 for UL or DL ​​communication in the active BWP. In some aspects, the BS 105 may allocate a pair of BWPs within the CC to the UE 115 for UL and DL communication. For example, the BWP pair may include one BWP for UL communication and one BWP for DL ​​communication.

[0063] In some aspects, the network 100 may operate in an unlicensed band with restrictive PSD requirements, or operate over a wide area (in a licensed band or an unlicensed band) where extended range is desired. In order to enable the UE 115 to access the network 100 and synchronize with the BS 105, the network 100 may allow the UE 115 to send a random access preamble using multiple ROs. In some instances, the random access preamble transmission based on multiple ROs may be performed over multiple ROs in frequency. In some other instances, the random access preamble transmission based on multiple ROs may be performed over multiple ROs in time.

[0064] As discussed above, the UE may monitor the RAR after sending a random access preamble based on a RA-RNTI, which is determined based on the random access resource or RO used for the random access preamble transmission. In order to facilitate the UE 115 to monitor the RAR of the random access preamble transmitted using multiple ROs, a set of rules may be defined to determine the (multiple) RA-RNTIs and / or RAR windows for the random access preamble transmission based on multiple ROs. The set of rules may be predetermined or indicated by the BS 105, for example, in the RMSI and / or OSI. In some aspects, the set of rules may specify a predetermined RO among multiple ROs for determining a single RA-RNTI for multiple ROs. Therefore, the UE 115 may determine a single RA-RNTI based on a predetermined RO among multiple ROs, and monitor the RAR of the random access preamble based on the single RA-RNTI. When the BS 105 detects any part of the random access preamble in any RO of the multiple ROs, the BS 105 may respond by sending the RAR based on the single RA-RNTI determined from the predetermined RO.

[0065] In some aspects, the set of rules may specify that the RA-RNTI is determined for each of the multiple ROs on a per-RO basis. In other words, there may be multiple RA-RNTIs associated with a single multi-RO based random access preamble transmission. Therefore, the UE 115 may determine the RA-RNTI for each of the multiple ROs based on each corresponding RO, and monitor the RAR of the random access preamble based on each RA-RNTI. The BS 105 may respond to each part of the random access preamble based on the RA-RNTI determined from the RO that detected the corresponding part. In some other instances, the BS 105 may not respond to one of the detected parts of the random access preamble, rather than all the detected parts of the random access preamble.

[0066] In some aspects, UE 115 may determine whether to determine a single RA-RNTI or multiple RA-RNTIs for multiple ROs based on whether the multiple ROs are dedicated to random access based on multiple ROs or random access based on a single RO. In some other aspects, the set of rules may specify a new function for determining the RA-RNTIs for multiple ROs. For example, the function may depend on the time and / or frequency position of each RO in the multiple ROs. Therefore, UE 115 may determine a single RA-RNTI based on multiple ROs. In some aspects, UE 115 may start RAR monitoring after a certain RO in the multiple ROs, which may be based on preconfiguration or indicated by BS105. This article describes in more detail the mechanism for performing random access based on multiple ROs.

[0067] Figure 2 A radio frame structure 200 according to some aspects of the present disclosure is illustrated. Radio frame structure 200 may be employed by a BS such as BS 105 and a UE such as UE 115 in a network such as network 100 for communication. In particular, the BS may communicate with the UE using time-frequency resources configured as shown in radio frame structure 200. Figure 2 , the x-axis represents time in some arbitrary units and the y-axis represents frequency in some arbitrary units. Transmission frame structure 200 includes radio frame 201. The duration of radio frame 201 can vary according to various aspects. In one example, radio frame 201 can have a duration of about ten milliseconds. Radio frame 201 includes M number of time slots 202, where M can be any suitable positive integer. In one example, M can be about 10.

[0068] Each time slot 202 includes a plurality of subcarriers 204 in frequency and a plurality of symbols 206 in time. The number of subcarriers 204 and / or the number of symbols 206 in the time slot 202 may vary according to various aspects based on, for example, the channel BW, subcarrier spacing (SCS), and / or CP mode. One subcarrier 204 in frequency and one symbol 206 in time form one resource element (RE) 212 for transmission. A resource block (RB) 210 is formed by a plurality of consecutive subcarriers 204 in frequency and a plurality of consecutive symbols 206 in time.

[0069] In one example, a BS (e.g., Figure 1 BS 105 in the example may schedule UEs (eg, Figure 1 UE 115 in the UE 115) for UL and / or DL ​​communication. Each time slot 202 can be time-divided into K mini-time slots 208. Each mini-time slot 208 can include one or more symbols 206. The mini-time slots 208 in the time slot 202 can have variable lengths. For example, when the time slot 202 includes N number of symbols 206, the mini-time slot 208 can have a length between one symbol 206 and (N-1) symbols 206. In some aspects, the mini-time slot 208 can have a length of about two symbols 206, about four symbols 206, or about seven symbols 206. In some examples, the BS can schedule UEs with a frequency granularity of a resource block (RB) 210 (e.g., including about 12 subcarriers 204).

[0070] FIG. 3A to FIG. 3C Discussed in relation to each other to illustrate the four-step random access process. Figure 3A is a signaling diagram of a random access method 300 for performing a four-step random access process according to an embodiment of the present disclosure. The steps of method 300 can be performed by a computing device (e.g., a processor, a processing circuit, and / or other suitable components) of a wireless communication device (such as a BS 105 and a UE 115). As shown, method 300 includes a plurality of enumerated steps, but an embodiment of method 300 may include additional steps before, after, and between the enumerated steps. In some embodiments, one or more of the enumerated steps may be omitted or performed in a different order. For the purpose of simplicity of discussion, method 300 shows a BS 105 and a UE 115, but it will be appreciated that embodiments of the present disclosure may be extended to more UEs 115 and / or BS 105.

[0071] At action 310, UE 115 sends MSG1 carrying a random access preamble according to the PRACH configuration. For example, BS 105 may broadcast the PRACH configuration in the SIB. The PRACH configuration may indicate, for example, a random access preamble format in a random access preamble pool. The PRACH configuration may also indicate a random access opportunity (e.g., time-frequency resource or RE 212) that may be used to send a random access preamble. In some instances, MSG1 also includes a payload and a random access identifier (ID). The random access ID of a specific random access preamble sent may be derived based on the frequency-time resource used by UE 115 to send a specific random access preamble. Therefore, there is a one-to-one mapping between RO and random access ID. The random access ID is referred to as RA-RNTI.

[0072] Figure 3B A random access preamble transmission scheme 330 according to some aspects of the present disclosure is shown. The UE 115 and the BS 105 may communicate using the scheme 330. The x-axis represents time in some arbitrary units. The y-axis represents frequency in some arbitrary units. For example, the PRACH configuration may indicate a plurality of ROs 302. The ROs 302 are shown as 302a, 302b, 302c, and 302d, and are denoted as RO1, RO2, RO3, and RO4, respectively. Although Figure 3B Four ROs 302 at different times are shown, but it should be understood that in other examples, there may be any suitable number of ROs 302 located at any suitable time and / or frequency locations. In the example shown in FIG3 , the UE 115 transmits a PRACH preamble sequence 332 in a single RO 302a. The PRACH preamble sequence 332 may correspond to the random access preamble transmitted by the UE 115 at action 310. The PRACH preamble sequence 332 is a physical waveform sequence.

[0073] Back to Figure 3A At action 312, after sending MSG1, UE 115 monitors MSG2 from BS 105 within a RAR window (e.g., RAR window 304 in FIG. 3B ). In some instances, UE 115 sends a random access preamble in mini-slot I of the Kth subframe, and the corresponding RAR window starts at mini-slot J of the (N+K)th subframe and spans a duration L, where N may be greater than or equal to 0, and J and L may be defined in one of the SIBs broadcast by BS 105. UE 115 monitors the RAR based on the random access ID to identify whether the received RAR is a response to the random access preamble sent by UE 115.

[0074] At action 314, upon detecting MSG1, BS 105 processes MSG 1. For each detected random access preamble, BS 105 may determine the UL transmit timing of UE 115 and allocate UL resources and a temporary ID to UE 115 for sending subsequent messages. BS 105 may allocate UL resources based on the random access message transmission configuration (e.g., tone spacing, symbol timing, start time, and / or end time of UL control and data channels). BS 105 may identify a subsequent (or next) random access message (e.g., MSG3) from UE 115 by a temporary ID. The temporary ID is referred to as a temporary C-RNTI.

[0075] At action 316, for each detected random access preamble, BS 105 sends MSG2 according to the random access message sending configuration. MSG2, as a RAR, is a response to the random access preamble received from UE 115 at action 310. The RAR can be carried in one or more mini-slots or one or more time slots. Each RAR may include a control part (e.g., in the PDCCH) and a data part (e.g., in the PDSCH). MSG2 carries an UL grant, which UE 115 can use to send content to BS 105. The control part is generated based on the random access ID of the corresponding random access preamble. The data part carries the corresponding allocated resources, the corresponding allocated temporary ID, and the corresponding timing advance information determined based on the corresponding uplink transmission timing. In some instances, MSG 2 includes allocated resources, temporary ID, and timing advance information.

[0076] Figure 3CA RAR transmission scheme 340 is shown according to some aspects of the present disclosure. The UE 115 and the BS 105 may communicate using the scheme 340. The x-axis represents time in some arbitrary units. The y-axis represents frequency in some arbitrary units. For example, the BS 105 transmits a PDCCH 350 based on a RA-RNTI associated with a random access preamble (e.g., a PRACH preamble sequence 332) transmitted by the UE 115 at action 310. The RA-RNTI may be a function of the time and / or frequency resources of the RO 302a (RO1) where the UE 115 transmits the PRACH preamble sequence 332. The PDCCH 350 may be transmitted in a control portion 342 of a time slot 202. The time slot 202 may correspond to a time slot within a RAR window 304. The PDCCH 350 may indicate the scheduling of the MSG2 352 in a data portion 346 of the time slot 202. MSG2 352 may correspond to MSG2 sent by BS 105 at act 316. In some aspects, PDCCH 350 includes a DCI including a cyclic redundancy check (CRC) masked by the RA-RNTI (e.g., by scrambling a cyclic redundancy check (CRC) with the RA-RNTI). In some aspects, MSG2 352 may include a record of the PRACH preamble sequence 332 to which MSG2 352 is responding.

[0077] Back to Figure 3A At action 318, upon detecting MSG2, UE 115 processes MSG 2. For example, UE 115 retrieves allocated resources, temporary ID, and timing advance information from MSG2.

[0078] At action 320, UE 115 sends MSG3 carrying a connection request (RRC Connection Request) to BS 105. In one example, UE 115 responds to the RAR received from BS 105 by sending MSG 3. MSG3 may be sent according to the allocated resources, temporary ID, timing advance information, and random access message transmission configuration. MSG3 may be carried in one or more mini-slots or one or more time slots.

[0079] At action 322, upon receiving MSG3, BS 105 processes MSG 3 and determines that MSG3 is sent in response to the RAR via the temporary ID. Therefore, BS 105 determines that the UE assigned to the temporary ID desires to connect to the network. At action 324, BS 105 confirms receipt of MSG 3 by sending MSG 4 carrying a connection response (RRC connection response) to UE 115. MSG4 may be carried in one or more mini-slots or one or more time slots.

[0080] UE 115 may then send an ACK for MSG 4 to BS 105 and continue to initiate the registration process with BS 105.

[0081] As discussed above, UE 115 may also perform a two-step random access procedure, where UE 115 sends an MSGA and BS 105 may respond with an MSGB. The MSGA may include a random access preamble (e.g., PRACH preamble sequence 352) and a connection request. The MSGB may include an RAR and a connection response. UE 115 may send the MSGA in a RO similar to RO 302. The BS may, for example, use the same Figure 3C A similar mechanism is shown for the transmission of MSG2 to transmit MSGB based on the RA-RNTI derived from the RO that detected MSGA.

[0082] As discussed above, in some network deployments, it may be desirable for a UE 115 to transmit a random access preamble in a frequency band (e.g., an unlicensed band) using multiple ROs in the frequency, e.g., to increase the frequency BW occupancy so that the UE 115 does not have to reduce its transmit power (e.g., about 23 dBm) and still meet a specific PSD requirement for the frequency band. Similarly, it may be desirable for a coverage-limited UE 115 to transmit a random access preamble using multiple ROs in time, e.g., to allow the BS 105 to collect more power for random access preamble detection.

[0083] Figure 4 A random access preamble transmission scheme 400 using multiple ROs according to some aspects of the present disclosure is shown. The UE 115 and the BS 105 can use the scheme 400 for communication. The x-axis represents time in some arbitrary units. The y-axis represents frequency in some arbitrary units. As shown, the scheme 400 includes multiple ROs 402 in time. The ROs 402 are shown as 402a, 402b, 402c, and 402d, and are respectively denoted as RO1, RO2, RO3, and RO4. Each RO 402 can be in a similar manner to Figure 2414, and 416. The RO 402 may be in a time slot of a time slot 202 of the RO. The RO 402 may be in a continuous time slot or a non-continuous time slot. The RO 420 may occupy the entire time slot 202 or a portion of the time slot 202. The UE 115 may initiate network access with the BS 105 by sending a random access preamble including a PRACH preamble sequence portion 1 410, a PRACH preamble sequence portion 2 412, a PRACH preamble sequence portion 3 414, and a PRACH preamble sequence portion 4 416. The UE 115 may send each of the PRACH preamble sequences 410, 412, 414, and 416 in one of the multiple ROs 402. The PRACH preamble sequences 410, 412, 414, and 416 are physical waveform sequences. In some aspects, each of the PRACH preamble sequences 410, 412, 414, and 416 corresponds to the same PRACH preamble sequence. In other words, the UE 115 sends four repetitions of the PRACH preamble sequence. In some other aspects, the PRACH preamble sequences 410, 412, 414, and 416 are associated with each other to form a long random access preamble for transmission on multiple ROs 402. For example, the PRACH preamble sequences 410, 412, 414, and 416 can be in a random access preamble pool, and the random access preamble pool can be defined with the association of the PRACH preamble sequences 410, 412, 414, and 416. Although Figure 4 The UE 115 is shown sending the random access preamble in four ROs 402 (e.g., four time slots 202), but it should be understood that in other examples, the UE 115 can send the random access preamble in any suitable number of ROs 402 (e.g., approximately 2, 3, 5, or more ROs).

[0084] Figure 5 A random access preamble transmission scheme 500 using multiple ROs according to some aspects of the present disclosure is shown. The UE 115 and the BS 105 can use the scheme 500 for communication. The x-axis represents time in some arbitrary units. The y-axis represents frequency in some arbitrary units. As shown, the scheme 500 includes multiple ROs 502 in frequency. The ROs 502 are shown as 502a, 502b, 502c, and 502d, and are represented as RO1, RO2, RO3, and RO4, respectively. Each RO 502 may include a signal similar to Figure 2514, 516. The RO 502 may be in a set of RBs of RB 210 of the UE 105. The RO 502 may be in a continuous RB set or a non-contiguous RB set. The UE 115 may initiate network access with the BS 105 by sending a random access preamble including a PRACH preamble sequence portion 1 510, a PRACH preamble sequence portion 2 512, a PRACH preamble sequence portion 3 514, and a PRACH preamble sequence portion 4 516. The UE 115 may send each of the PRACH preamble sequences 510, 512, 514, and 516 in one of the plurality of ROs 502. The PRACH preamble sequences 510, 512, 514, and 516 are physical waveform sequences. In some aspects, each of the PRACH preamble sequences 510, 512, 514, and 516 corresponds to the same PRACH preamble sequence. In other words, the UE 115 sends four repetitions of the PRACH preamble sequence. In some other aspects, the PRACH preamble sequences 510, 512, 514, and 516 are associated with each other to form a long random access preamble for transmission on multiple ROs 502. Figure 5 The UE 115 is shown transmitting the random access preamble in four ROs 502 (eg, four groups of RBs 210), but it will be appreciated that in other examples, the UE 115 may transmit the random access preamble in any suitable number of ROs 502 (eg, approximately 2, 3, 5, or more ROs).

[0085] In some aspects, the UE 115 may implement the method 300 in conjunction with the scheme 400. For example, at act 310, the UE 115 may transmit MSG1 including a random access preamble using multiple ROs 402 in time, the random access preamble including PRACH preamble sequences 410, 412, 414, and 416. In some other aspects, the UE 115 may implement the method 300 in conjunction with the scheme 500. For example, at act 310, the UE 115 may transmit a random access preamble using multiple ROs 402 in frequency, the random access preamble including PRACH preamble sequences 510, 512, 514, and 516. In some other aspects, as Figure 4 As shown, UE 115 may transmit a MSGA including a random access preamble using multiple ROs 402 at a time, the random access preamble including PRACH preamble sequences 410, 412, 414, and 416. In some other aspects, as Figure 5 As shown, UE 115 may transmit a MSGA including a random access preamble including PRACH preamble sequences 510, 512, 514, and 516 using multiple ROs 402 on a frequency.

[0086] To facilitate UE 115 monitoring random access preambles transmitted using multiple ROs in MSG2 or MSGB, the present disclosure provides techniques for determining RA-RNTI(s) when UE 115 utilizes multiple ROs for random access preamble transmission.

[0087] Figure 6 A random access preamble transmission scheme 600 using multiple ROs according to some aspects of the present disclosure is shown. Scheme 600 may be used by UE 115 and BS 105 in a network such as network 100 for communication. In some aspects, BS 105 and UE 115 may employ scheme 600 in conjunction with method 300. The x-axis represents time in some arbitrary units. The y-axis represents frequency in some arbitrary units. Scheme 600 is shown using the same RO configuration (with multiple ROs in time) and random access preamble transmission configuration as scheme 400, and for simplicity, the same scheme may be used. Figure 4 Although the scheme 600 is illustrated using multiple ROs in time, it should be understood that a similar RA-RNTI determination mechanism can be applied to multiple ROs in frequency, such as Figure 5 shown.

[0088] In scheme 600, BS 105 may send a configuration indicating a random access preamble sequence pool for random access based on multiple ROs. The configuration may also indicate an RO pool for random access. BS 105 may indicate the configuration in an SIB. UE 115 may select a random access preamble from the random access preamble pool, and select multiple ROs from the RO pool, and send the random access preamble in the selected multiple ROs. Figure 6 In the example shown, the UE 115 transmits a random access preamble including PRACH preamble sequences 410, 412, 414, and 416, each in one of a plurality of ROs 402a, 402b, 402c, and 402d. The UE 115 may determine a single RA-RNTI 620 for the plurality of ROs 402 transmitting the random access preambles.

[0089] In some aspects, the UE 115 may determine a single RA-RNTI 620 based on a predetermined RO in the RO 402. The UE 115 may determine the RA-RNTI 620 using a substantially similar mechanism in the single RO based random access preamble transmission in the method 300 discussed above with respect to FIG. 3. For example, the predetermined RO may correspond to the RO 402b (RO1). Therefore, the UE 115 may determine the single RA-RNTI 620 based on the time and / or frequency resources of the RO 402b. For example, the UE 115 may calculate the single RA-RNTI 620 according to equation (1):

[0090] RA-RNTI=1+s_id+14×t_id+14×80×f_id+14×80×8×ul_carrier_id (1)

[0091] Wherein, s_id represents the index of the first OFDM symbol of the predetermined RO (e.g., 0≥s_id<14), t_id represents the index of the first time slot symbol of the predetermined RO in the system frame (e.g., 0≥t_id<80), f_id represents the index of the predetermined RO in the frequency domain (e.g., 0≥s_id<8), and ul_carrier_id represents the UL carrier used for random access preamble code transmission (e.g., 0=normal carrier, 1=supplementary UL carrier).

[0092] In some aspects, the predetermined RO may be specified by a wireless communication standard such as 3GPP. In some aspects, for example, in a PRACH configuration, the BS 105 may indicate a predetermined RO among multiple ROs 402 for use in determining a single RA-RNTI 620. In some instances, the predetermined RO may correspond to an earliest RO (RO1) or earliest repetition among the ROs 402. In some instances, the predetermined RO may correspond to a last RO (RO4) or last repetition among the ROs 402. In general, the predetermined RO may be any RO (e.g., the kth RO) among a set of multiple ROs 402 for multi-RO based random access preamble transmission. In Figure 6 In the example shown, BS 105 indicates a second RO (RO1) as a predetermined RO for RA-RNTI calculation. Therefore, UE 115 can monitor the RAR in RAR window 604 (e.g., MSG2 in four-step random access and MSGB in two-step random access) based on a single RA-RNTI 620 determined from RO1 (time / frequency resource), and BS 105 can respond to the random access preamble based on RA-RNTI 620. For example, BS 105 can send a PDCCH with a CRC masked by a single RA-RNTI 620, wherein the PDCCH can include a schedule for MSG2 or MSGB for UE 115, for example, similar to the above description of Figure 3C RAR transmission in scheme 340 discussed.

[0093] In some aspects, the RAR window 604 may be specified by a wireless communication standard such as 3GPP. In some aspects, the BS 105 may indicate the configuration of the RAR window 604. In some instances, the RAR window 604 may start after the earliest RO (e.g., RO1) or repetition in a group of multiple ROs 402. In some instances, the RAR window 604 may start after the last RO (RO4) or repetition in a group of multiple ROs 402. In some instances, the RAR window 604 may be defined in the same manner regardless of whether the UE 115 uses a single RO-based random access preamble or a multi-RO-based random access preamble for random access. For example, the RAR window 604 may start K time slots after the RO used for random access preamble transmission. In general, the RAR window 604 may start after any RO in the group of multiple ROs 402. If the UE 115 fails to detect any RAR from the BS 105 within the RAR window 604, the UE 115 may retry sending another random access preamble in another set of multiple ROs 402 after the RAR window 604, e.g., after a backoff. The UE 115 may select the same set of PRACH preamble sequences 410, 412, 414, and 416 or a different set of PRACH preamble sequences.

[0094] In some aspects, when the BS 105 desires to attempt early decoding or detection of a random access preamble, the BS 105 may configure an earlier RO of the plurality of ROs 402 as a predetermined RO to allow the UE 115 to monitor the RAR with a potential early decision from the BS 105. For example, as shown, when the RAR window 604 begins after the earliest repetition or RO 402a, the BS 105 may send a RAR to the UE 115 upon detecting a PRACH preamble sequence portion 1410 at the beginning of the RAR window 604. Depending on when the UE receives the RAR, the UE 115 may not send all of the PRACH preamble sequences 410, 412, 414, and 416. For example, if the UE receives the RAR before the third RO 402c, the UE may not send PRACH preamble sequence portion 3416 in RO 402c and PRACH preamble sequence portion 4418 in RO 402d.

[0095] In some aspects, the BS 105 may desire to send the RAR (MSG2 or MSGB) as a broadcast message. For example, if the BS 105 detects two random access preambles from two UEs 115 in an RO (e.g., RO1), the BS 105 may send a single MSG2 or MSGB including a RAR for each detected random access preamble based on the RA-RNTI determined from RO1 in response to the two UEs 115. However, when the random access preamble transmission based on a single RO and the random access preamble transmission based on multiple ROs share the same RO pool, using a single RA-RNTI for the random access preamble transmission based on multiple ROs may limit the use of the broadcast MSG2 or MSGB. For example, the BS 105 detects a PRACH preamble sequence portion 1410 from a UE 115 based on multiple RO access in the RO 402a (RO0), and a random access preamble from a random access preamble based on a single RO access in the RO 402a (RO0). Since the UE 115 based on multi-RO access monitors the RAR based on the RA-RNTI (e.g., RA-RNTI A) determined from the predetermined RO1, and the UE 115 based on single RO access monitors the RAR based on the RA-RNTI (e.g., RA-RNTI B) determined from RO0 (where the UE 115 based on single RO access has transmitted the random access preamble), the BS 105 will have to transmit one RAR for the UE 115 based on multi-RO access based on RA-RNTI A, and another RAR for the UE 115 based on single RO access based on RA-RNTI B. Therefore, in some aspects, it may be desirable to have a one-to-one correspondence between RA-RNTI and RO 402, so that the BS 105 can respond to the UE 115 based on multi-RO access and the UE 115 based on single RO access in a single broadcast MSG2 or MSGB to reduce network signaling overhead.

[0096] Figure 7 A random access preamble transmission scheme 700 using multiple ROs is shown in accordance with some aspects of the present disclosure.

[0097] Scheme 700 may be used by UE 115 and BS 105 in a network such as network 100 for communication. In some aspects, BS 105 and UE 115 may employ scheme 700 in conjunction with method 300. The x-axis represents time in some arbitrary units. The y-axis represents frequency in some arbitrary units. Scheme 700 is illustrated using the same RO configuration (with multiple ROs in time) and random access preamble transmission configuration as scheme 400, and for simplicity, may be used. Figure 4Although the scheme 700 is illustrated using multiple ROs in time, it should be understood that a similar RA-RNTI determination mechanism can be applied to multiple ROs in frequency, such as Figure 5 shown.

[0098] Similar to the scheme 600, the BS 105 may indicate a pool of random access preambles and a pool of ROs for random access. However, in the scheme 700, the UE 115 may determine multiple RA-RNTIs for multiple ROs 402 for which the UE 115 transmits random access preambles. For example, the UE 115 may determine the RA-RNTI for each RO 402 based on the corresponding RO 402. As shown, the UE 115 may determine the RA-RNTI 720 based on the RO0 (e.g., RO 402a) that transmits the PRACH preamble sequence portion 1 410. The UE 115 may also determine the RA-RNTI 722 based on the RO1 (e.g., RO 402b) that transmits the PRACH preamble sequence portion 2 412. The UE 115 may also determine the RA-RNTI 724 based on the RO2 (e.g., RO 402c) that transmits the PRACH preamble sequence portion 3 414. UE 115 may also determine RA-RNTI 726 based on RO3 (e.g., RO 402d) that sent PRACH preamble sequence portion 4 416. In some examples, UE 115 may determine RA-RNTI 726 based on the above description of Figure 6 Equation (1) is discussed to determine each of RA-RNTI 720, 722, 724, and 726.

[0099] After determining multiple RA-RNTIs 720, 722, 724, and 726 for multiple ROs 402, UE 115 may monitor RARs based on multiple RA-RNTIs 720, 722, 724, and 726. Monitoring based on multiple RA-RNTIs 720, 722, 724, and 726 does not increase the number of PDCCH blind decodings at UE 115, but increases the number of CRC mask checks. For example, UE 115 may apply a first mask to a CRC in a detected PDCCH using RA-RNTI 720 (e.g., by scrambling the RC with RA-RNTI 720). If the CRC check fails, UE 115 may apply a second mask to the CRC using RA-RNTI 722. If the CRC check fails, UE 115 may apply a third mask to the CRC using RA-RNTI 724, and so on. For a UE 115 performing initial network access, the additional complexity associated with the additional CRC mask check may be low and affordable.

[0100] about Figure 7Discussed FIG. 8A to FIG. 8C 4 is used to illustrate various mechanisms that BS 105 may use to respond to UE 115 sending PRACH preamble sequences 410, 412, 414, and 416 in multiple ROs 402 based on multi-RO access. FIG. 8A to FIG. 8C , the x-axis represents time in some arbitrary units, and the y-axis represents frequency in some arbitrary units. Schemes 802, 804, and 806 may be used by BS 105 and UE 115 in a network such as network 100 for communication. In addition, schemes 802, 804, and 806 are shown using a PDCCH / MSG transmission configuration similar to schemes 330 and 340, and for simplicity, the same may be used. Figure 3B and Figure 3C Same reference numerals.

[0101] Fig. 8A A RAR transmission scheme 802 for a multi-RO based random access preamble according to some aspects of the present disclosure is shown. In the scheme 802, the BS 105 may include a RAR for a UE 115 based on multi-RO access in one MSG2 based on one RO among multiple ROs 402. In other words, the BS 105 may detect one or more of the PRACH preamble sequences 410, 412, 414, and 416, but may respond to one of the PRACH preamble sequences 410, 412, 414, and 416. For example, the BS 105 detects the PRACH preamble sequence portion 1 410 in the RO 402a (RO0) and the PRACH preamble sequence portion 2 412 in the RO 402b (RO1) from the multi-RO based random access preamble transmission, and decides to respond to the PRACH preamble sequence portion 1410. Thus, the BS 105 may send a first PDCCH 810 in the control portion 342 of the slot 202 based on the first RA-RNTI (RA-RNTI 720) calculated from RO0. The PDvCH 810 includes a CRC masked by the first RA-RNTI. In response to receiving the PRACH preamble sequence portion 1 410, the PDCCH 810 schedules a first RAR message 812 (e.g., MSG2 in a four-step random access and MSGB in a two-step random access) in the data portion 346 of the slot 202. Thus, the BS 105 may send the first RAR message 812 in the data portion 346 of the slot 202. The first RAR message 812 may include the PRACH preamble sequence portion 1 410 as part of the response in the first RAR message 812. In some other examples, the BS 105 may determine the response PRACH preamble sequence portion 2 412 instead of the PRACH preamble sequence portion 1 410 , for example, using a similar mechanism as discussed for the response PRACH preamble sequence portion 1 410 .

[0102] In some instances, the BS 105 may also detect a random access preamble (e.g., RO-based PRACH 808) from a UE 115 based on single RO access in RO 402b (RO1). The BS 105 may determine to respond to the single RO-based PRACH 808 in the same time slot 202. Therefore, the BS 105 may send a second PDCCH 820 in the control portion 342 of the time slot 202 based on the second RA-RNTI (RA-RNTI 722) calculated from RO1. The PDCCH 820 includes a CRC masked by the second RA-RNTI. In response to receiving the single RO-based PRACH 806, the PDCCH 820 schedules a second RAR message 822 in the data portion 346 of the time slot 202 (e.g., MSG2 in four-step random access and MSGB in two-step random access). Therefore, the BS 105 sends the second RAR message 822 in the data portion 346 of the time slot 202. In response to the single-RO based PRACH 806, the second RAR message 822 may include the single-RO based PRACH 806. Although the BS 105 also detects the PRACH preamble sequence portion 2412 in RO1, the BS 105 may not include the PRACH preamble sequence portion 2412 in the second RAR message 822 because the first RAR message 810 has already responded to the PRACH preamble sequence portion 1410.

[0103] The UE 115 may detect the first PDCCH 810 based on the first RA-RNTI (RA-RNTI 720) and the second PDCCH 820 based on the second RA-RNTI (RA-RNTI 722). Since the UE 105 may not know which PRACH preamble sequence 410, 412, 414, or 416 the BS 105 may detect, the UE 115 may decode the first RAR message 812 based on the scheduling in the first PDCCH 810 and decode the second RAR message 822 based on the scheduling in the second PDCCH 820. After decoding the first RAR message 812 and the second RAR message 822, the UE 115 may obtain the RAR of the PRACH preamble sequence portion 1410 from the first RAR message 812. Decoding two PDSCHs (e.g., the first RAR message 812 and the second RAR message 822) in a single slot 202 may be processing intensive. However, since the UE 115 may have no other important processing ongoing during random access, the UE 115 may be able to support two PDSCH decodes in a single time slot 202 .

[0104] In some other aspects, the BS 105 may determine whether to respond to the PRACH preamble sequence portion 410 detected in RO0 or the PRACH preamble sequence portion 2412 detected in RO1 depending on whether the BS 105 detects another random access preamble from another UE 115 in RO0 or RO1. For example, since the BS 105 also detects the single-RO-based PRACH 808 in RO1, the BS 105 may broadcast a RAR MSG based on the RA-RNTI 722 calculated from RO1 to respond to both the PRACH preamble sequence portion 2412 and the single-RO-based PRACH 808 instead of the separate RARMSG 812 and RAR MSG 822 as shown, thereby saving signaling overhead. For example, the RAR message may include the PRACH preamble sequence portion 2410 and the single-RO-based PRACH 808.

[0105] Figure 8B A RAR transmission scheme 804 for a multi-RO based random access preamble according to some aspects of the present disclosure is shown. Scheme 804 may be substantially similar to scheme 802. For example, the BS 105 may detect one or more of the PRACH preamble sequences 410, 412, 414, and 416, but may respond to one of the PRACH preamble sequences 410, 412, 414, and 416. In addition, the BS 105 may not transmit multiple RAR messages associated with the multi-RO based random access preamble transmission in the same time slot 202, so that the UE 115 based on multi-RO access does not have to decode multiple PDSCHs in a single time slot 202. Referring to the above description of Fig. 8A In the same example discussed above, the BS 105 detects the PRACH preamble sequence portion 1 410 in the RO 402a (RO0) and the PRACH preamble sequence portion 2 412 in the RO 402b (RO1) from the multi-RO based random access preamble transmission, and decides to respond to the PRACH preamble sequence portion 1 410. In addition, the BS 105 detects the random access preamble (e.g., RO based PRACH 808) from the UE 115 in the RO 402b (RO1) based on single RO access.

[0106] In response to the PRACH preamble sequence portion 1410, the BS 105 may transmit a first PDCCH 830 in the control portion 342 of the first slot 202a based on the first RA-RNTI (RA-RNTI 720) calculated from RO0. The PDCCH 830 schedules a first RAR message 832 (e.g., MSG2 in a four-step random access and MSGB in a two-step random access) in the data portion 346 of the first slot 202a. The BS 105 transmits the first RAR message 832 in the data portion 346 of the first slot 202a according to the PDvCH 830. In response to detecting the PRACH preamble sequence portion 1410, the first RAR message 832 may include the PRACH preamble sequence portion 1410.

[0107] In response to the single-RO based PRACH 806, the BS 105 may send a second PDvCH 840 in the control portion 342 of the second time slot 202b based on the second RA-RNTI (RA-RNTI 722) calculated from RO1. In some instances, as shown, the second time slot 202b may be spaced apart from the first time slot 202a. In some other instances, the first time slot 202a and the second time slot 202b may be consecutive time slots 202. The PDCCH 840 schedules a second RAR message 842 (e.g., MSG2 in a four-step random access and MSGB in a two-step random access) in the data portion 346 of the second time slot 202b. The BS 105 sends the second RAR message 842 in the data portion 346 of the second time slot 202b according to the PDCCH 840. In response to the single-RO based PRACH 806, the second RAR message 842 may include the single-RO based PRACH 806. Similar to scenario 804 , although BS 105 also detects PRACH preamble sequence part 2 412 in RO1 , BS 105 may not include PRACH preamble sequence part 2 412 in the second RAR message 842 because the first RAR message 832 already responded to PRACH preamble sequence part 1 410 .

[0108] Figure 8C A RAR transmission scheme 806 for a random access preamble based on multiple ROs according to some aspects of the present disclosure is shown. In scheme 806, if multiple PRACH preamble sequences 410, 412, 414, and 416 are detected, the BS 105 may respond to them. Fig. 8AIn the same example discussed, the BS 105 detects the PRACH preamble sequence portion 1 410 in the RO 402a (RO0) and the PRACH preamble sequence portion 2 412 in the RO 402b (RO1) from the multi-RO based random access preamble transmission, and decides to respond to the PRACH preamble sequence portion 1 410. In addition, the BS 105 detects the random access preamble (e.g., RO based PRACH 808) from the UE 115 in the RO 402b (RO1) based on the single RO access.

[0109] In response to the PRACH preamble sequence portion 1410, the BS 105 may transmit a first PDCCH 850 in the control portion 342 of the time slot 202 based on the first RA-RNTI (RA-RNTI 720) calculated from RO0. The PDCCH 850 schedules a first RAR message 852 (e.g., MSG2 in a four-step random access and MSGB in a two-step random access) in the data portion 346 of the time slot 202. The BS 105 transmits the first RAR message 852 in the data portion 346 of the time slot 202 according to the PDCCH 850. In response to detecting the PRACH preamble sequence portion 1 410, the first RAR message 852 may include the PRACH preamble sequence portion 1 410.

[0110] In response to the single-RO based PRACH 806, the BS 105 may send a second PDCCH 860 in the control portion 342 of the same slot 202 based on the second RA-RNTI (RA-RNTI 722) calculated from RO1. The PDCCH 860 schedules a second RAR message 862 (e.g., MSG2 in four-step random access and MSGB in two-step random access) in the data portion 346 of the slot 202. The BS 105 sends the second RAR message 862 in the data portion 346 of the slot 202 according to the PDCCH 860. In response to the single-RO based PRACH 806, the second RAR message 862 may include the single-RO based PRACH 806. In response to detecting the PRACH preamble sequence portion 2 in RO2, the second RAR message 862 may also include the PRACH preamble sequence portion 2 412.

[0111] Although the UE 115 can detect the first PDCCH 850 based on the first RA-RNTI and the second PDCCH 860 based on the second RA-RNTI, the UE 115 can decode either the first RAR message 852 or the second RAR message 862 because the first RAR message 852 and the second RAR message 862 each include a corresponding PRACH preamble sequence 410 or 412, respectively. For example, if the UE 115 successfully decodes the first RAR message 852 and finds the PRACH preamble sequence portion 1 410 in the first RAR message 852, the UE 115 may not decode the second RAR message 862 to save processing power or resources. In some other instances, the UE 115 may also receive and decode the second RAR message 862 for more robust decoding.

[0112] In some aspects, BS 105 may configure some ROs (e.g., Fig. 9 901) for sharing between single-RO based random access and multi-RO based random access. BS 105 may also configure some ROs dedicated to multi-RO based random access (e.g., Fig. 9 RO 902). In some instances, the BS 105 may configure a first random access preamble pool for random access preamble transmission based on a single RO, and configure a second random access preamble pool for random access preamble transmission based on multiple ROs. The first pool may include random access preambles different from the second pool. The UE 115 based on single RO access may select a first random access preamble from the first pool, select a single RO from a shared RO, and send the first random access preamble in the single RO. The UE 115 based on multiple RO access may select a second random access preamble from the second pool, and select multiple ROs from a shared RO or a dedicated RO. For example, the second random access preamble may include a PRACH preamble sequence similar to the PRACH preamble sequences 410, 412, 414, and 416. The UE 115 based on multiple RO access may send a second random access preamble in the selected multiple ROs. Depending on whether the multiple ROs are selected from shared ROs or dedicated ROs, the UE 115 based on multi-RO access may apply the scheme 600 or the scheme 700 to determine the RA-RNTI for RAR monitoring, as described below in Fig. 9 discussed in .

[0113] Fig. 9900 is a flowchart of a random access method 900 according to some aspects of the present disclosure. Aspects of the method 900 may be performed by a computing device (e.g., a processor, a processing circuit, and / or other suitable components) of a wireless communication device or other suitable components for performing the steps. For example, a wireless communication device such as UE 115 or 1200 may utilize one or more components (such as a processor 1202, a memory 1204, a random access module 1208, a transceiver 1210, a modem 1212, and one or more antennas 1216) to perform the steps of the method 900. The method 900 may be implemented as described above. Figure 6 8. As shown, method 900 includes a plurality of enumerated steps, but aspects of method 900 may include additional steps before, after, and between the enumerated steps. In some aspects, one or more of the enumerated steps may be omitted or performed in a different order.

[0114] In method 900, a BS (eg, BS 105) may configure RO 901 to be shared between single-RO based random access and multi-RO based random access, and may configure RO 902 to be dedicated to multi-RO based random access. RO 901 and 902 may be substantially similar to RO 302, 402, and / or 502.

[0115] At block 910, a UE (e.g., a UE 115 based on multi-RO access) selects a plurality of ROs from a shared RO 901 or a dedicated RO 902. In some instances, the UE may select a plurality of ROs using one or more components, such as a processor 1202, a memory 1204, a random access module 1208, a transceiver 1210, a modem 1212, and / or one or more antennas 1216. In some instances, the UE may randomly select a plurality of ROs from a shared RO 901 or a dedicated RO 902. In some instances, the UE may determine whether to select a plurality of ROs from a shared RO 901 or a dedicated RO 902 based on the earliest upcoming RO. In some instances, the UE may determine whether to select a plurality of ROs from a shared RO 901 or a dedicated RO 902 based on a processing capability or pre-configuration of the UE.

[0116] At block 915, the UE transmits random access preambles in the plurality of ROs. The random access preambles may include PRACH preamble sequence parts 1, 2, 3, and 4, similar to PRACH preamble sequences 410, 412, 414, and 416, respectively. The UE may transmit each part of the PRACH preamble sequence in one of the plurality of ROs: part 1, part 2, part 3, and part 4. In some instances, the UE may transmit random access preambles in the plurality of ROs using one or more components, such as a processor 1202, a memory 1204, a random access module 1208, a transceiver 1210, a modem 1212, and / or one or more antennas 1216.

[0117] At block 920, the UE determines whether the plurality of ROs are selected from the shared RO 901 or the dedicated RO 902. If the plurality of ROs are selected from the dedicated RO 902, the UE proceeds to block 930. In some examples, the UE may utilize one or more components (such as the processor 1202, the memory 1204, the random access module 1208, the transceiver 1210, the modem 1212, and / or one or more antennas 1216) to determine whether the plurality of ROs are selected from the shared RO 901 or the dedicated RO 902.

[0118] At block 930, the UE determines the RO based on a predetermined RO (eg, using the RO described above). Figure 6 The UE may determine a single RA-RNTI for multiple ROs using the discussed scheme 600. The predetermined RO may be based on a wireless protocol standard such as 3GPP or broadcast by the BS 105. In some instances, the UE may utilize one or more components (such as the processor 1202, the memory 1204, the random access module 1208, the transceiver 1210, the modem 1212, and / or one or more antennas 1216) to determine a single RA-RNTI.

[0119] At block 935, the UE monitors the RAR message from the BS based on a single RA-RNTI. For example, the UE may monitor a PDCCH with a CRC masked by the RA-RNTI. If the UE successfully decodes the PDCCH with a CRC masked by the RA-RNTI, the UE decodes the PDSCH scheduled by the PDCCH and obtains the RAR from the decoded PDSCH. In some instances, the UE may monitor the RAR message based on a single RA-RNTI using one or more components (such as a processor 1202, a memory 1204, a random access module 1208, a transceiver 1210, a modem 1212, and / or one or more antennas 1216).

[0120] Returning to block 920, if multiple ROs are selected from the shared RO 901, the UE proceeds to block 940. At block 940, the UE uses, for example, the above description of Figure 7 The scheme 700 is discussed to determine a RA-RNTI (e.g., RA-RNTIs 720, 722, 724, and 72) for each of the multiple ROs. In some examples, the UE can utilize one or more components (such as the processor 1202, the memory 1204, the random access module 1208, the transceiver 1210, the modem 1212, and / or one or more antennas 1216) to determine each RA-RNTI for each of the multiple ROs.

[0121] At block 945, the UE monitors the RAR message from the BS based on the multiple RA-RNTIs. In some instances, the UE may monitor the RAR message based on the multiple RA-RNTIs using one or more components, such as a processor 1202, a memory 1204, a random access module 1208, a transceiver 1210, a modem 1212, and / or one or more antennas 1216. For example, the UE may monitor the RAR message during the RAR window based on at least one of a first RA-RNTI determined for a first RO in a plurality of ROs or a second RA-RNTI determined for a second RO in a plurality of ROs. In some aspects, the UE may receive a first PDCCH that schedules a first RAR message based on the first RA-RNTI, and receive the first RAR message based on the first PDCCH. The first RAR message may include a PRACH preamble sequence portion 1 sent in the first RO. The UE may also receive a second PDCCH that schedules a second RAR message based on a second RA-RNTI, for example, in the same time slot as the first PDCCH or in a time slot different from the first PDCCH. In some aspects, for example, based on the successful decoding of the first RAR message and receiving the RAR sent for the random access preamble (indicated by including the PRACH preamble sequence part 1 in the first RAR message), the UE may not receive and decode the second RAR message scheduled by the second PDCCH. In some other aspects, for example, for more robust decoding, the UE may also receive and decode the second RAR message scheduled by the second PDCCH.

[0122] Therefore, if the BS 105 detects a multi-RO based random access preamble from one or more ROs of the dedicated RO 902, the BS 105 may respond to the multi-RO based random access preamble based on a single RA-RNTI calculated from a predetermined RO among the multiple ROs. Alternatively, if the BS 105 detects a multi-RO based random access preamble from one or more ROs of the shared RO 901, the BS 105 may respond to the multi-RO based random access preamble based on the RA-RNTI calculated from the RO in which the PRACH preamble sequence portion is detected.

[0123] Fig.10 A random access preamble transmission scheme 1000 using multiple ROs according to some aspects of the present disclosure is shown. Scheme 1000 may be used by UE 115 and BS 105 in a network such as network 100 for communication. In some aspects, BS 105 and UE 115 may employ scheme 1000 in conjunction with method 300. The x-axis represents time in some arbitrary units. The y-axis represents frequency in some arbitrary units. Scheme 1000 is shown using the same RO configuration (with multiple ROs in time) and the same random access preamble transmission configuration as scheme 400, and for simplicity, may be used. Figure 4 Although the scheme 1000 is illustrated using multiple ROs in time, it should be understood that a similar RA-RNTI determination mechanism can be applied to multiple ROs in frequency, such as Figure 5 shown.

[0124] Similar to scheme 600, BS 105 may indicate a pool of random access preambles and a pool of ROs for random access in a PRACH configuration. However, in scheme 1000, UE 115 may determine RA-RNTI 1020 for multiple ROs 402, where UE 115 uses a new formula, for example, different from equation (1) to send a random access preamble. For example, the new formula may be a function of each RO 402 in the multiple ROs 402. The new function may be represented as F(RO1, RO2, ..., RO_K), where K is the last RO in the multiple ROs 402. In a system with four ROs 402, 1020 may be used to determine RA-RNTI 1020 for multiple ROs 402. Fig.10 In the example shown in , the new function can be represented by F(RO0, RO1, RO2, RO3). As an example, the new function can depend on the time position (e.g., starting symbol index and / or starting slot index) and frequency position (e.g., RB index, RB set index) of each RO in RO 402, as shown below:

[0125]

[0126] Wherein K represents a constant, r represents an RO index, R represents the number of ROs in the plurality of ROs 402, t represents timing information associated with the rth RO, f represents frequency information associated with the rth RO, and a and b are scaling factors.

[0127] In another example, a new function for calculating RA-RNTI for multiple ROs may be defined as follows:

[0128] RA-RNTI=K2+s_id+14×t_id+14×80×f_id+14×80×8×ul_carrier_id(3)

[0129] Wherein, K2 represents a constant, s_id represents the index of the first OFDM symbol of a RO within a plurality of ROs (e.g., 0≥s_id<14), t_id represents the index of the first time slot symbol of the RO in the system frame (e.g., 0≥t_id<80), f_id represents the index of the RO in the frequency domain (e.g., 0≥s_id<8), and ul_carrier_id represents the UL carrier used for random access preamble transmission (e.g., 0=normal carrier, 1=supplementary UL carrier). The RO can be the earliest RO, the last RO, or any RO among the plurality of ROs. The constant K2 can distinguish the RA-RNTI associated with a random access preamble based on multiple ROs from the RA-RNTI associated with a random access preamble based on a single RO.

[0130] Thus, the UE 115 may monitor the RAR in the RAR window 1004 (e.g., MSG2 in a four-step random access and MSGB in a two-step random access) based on the single RA-RNTI 1020 determined according to the new function, and the BS 105 may respond to the random access preamble based on the RA-RNTI 1020. For example, the BS 105 may send a PDCCH with a CRC masked by the single RA-RNTI 1020, wherein the PDCCH may include a schedule for MSG2 or MSGB for the UE 115, for example, similar to the above description of Figure 3C RAR transmission in scheme 340 discussed.

[0131] In some aspects, the new formula may be specified by a wireless communication standard such as 3GPP. In some aspects, the BS 105 may indicate the new formula, for example, in a PRACH configuration. In some aspects, the BS 105 may also indicate a configuration of a RAR window 1004, which the UE 115 may use for RAR monitoring. In some aspects, the RAR window 1004 may start after deviating from the earliest RO in the plurality of ROs, the last RO in the plurality of ROs, or any other RO in the plurality of ROs.

[0132] Fig.11 1 is a block diagram of an exemplary BS 1100 according to some aspects of the present disclosure. UE 1100 may be BS 105 in network 100, as described above in Figure 1 As shown, BS 1100 may include a processor 1102, a memory 1104, a random access module 1108, a transceiver 1110 including a modem subsystem 1112 and an RF unit 1114, and one or more antennas 1116. These elements may communicate with each other directly or indirectly, for example, via one or more buses.

[0133] The processor 1102 may have various characteristics as a specific type of processor. For example, these may include a CPU, a DSP, an ASIC, a controller, an FPGA device, another hardware device, a firmware device, or any combination thereof configured to perform the operations described herein. The processor 1102 may also be implemented as a combination of computing devices, for example, a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration.

[0134] The memory 1104 may include a cache memory (e.g., a cache memory of the processor 1102), RAM, MRAM, ROM, PROM, EPROM, EEPROM, flash memory, a solid-state memory device, one or more hard disk drives, a memristor-based array, other forms of volatile and nonvolatile memory, or a combination of different types of memory. In some aspects, the memory 1104 may include a non-transitory computer-readable medium. The memory 1104 may store instructions 1106. The instructions 1106 may include instructions that, when executed by the processor 1102, cause the processor 1102 to perform the operations described herein (e.g., Figure 2 , FIG. 3A to FIG. 3C , Figures 4 to 7 , FIG. 8A to FIG. 8C , Figures 9 and 10 and Fig.14 Instructions 1106 may also be referred to as program code. Program code may be used to cause a wireless communication device to perform these operations, for example, by causing one or more processors (such as processor 1102) to control or command the wireless communication device to perform these operations. The terms "instructions" and "code" should be broadly interpreted to include any type of computer-readable statements. For example, the terms "instructions" and "code" may refer to one or more programs, routines, subroutines, functions, programs, etc. "Instructions" and "code" may include a single computer-readable statement or multiple computer-readable statements.

[0135] The random access module 1108 may be implemented via hardware, software, or a combination thereof. For example, the random access module 1108 may be implemented as a processor, circuit, and / or instruction 1106 stored in the memory 1104 and executed by the processor 1102. In some cases, the random access module 1108 may be integrated within the modem subsystem 1112. For example, the random access module 1108 may be implemented by a combination of software components (e.g., executed by a DSP or general purpose processor) and hardware components (e.g., logic gates and circuits) within the modem subsystem 1112.

[0136] The random access module 1108 may be used in various aspects of the present disclosure, for example, Figure 2 , Figures 3A to 3C , Figures 4 to 7 , FIG. 8A to FIG. 8C , Figures 9 and 10 and Fig.14 Aspects of the present invention. The random access module 1108 is configured to send a configuration indicating a random access preamble for random access associated with multiple ROs, receive a random access preamble in one or more of the multiple ROs from a UE (e.g., UE 115 or 1200), determine one or more RA-RNTIs for the multiple ROs, and send a RAR message (e.g., MSG2 in four-step random access and MSGB in two-step random access) based on the one or more determined RA-RNTIs during a RAR window associated with the multiple ROs. In some aspects, the random access preamble may include multiple PRACH preamble sequences similar to the PRACH preamble sequences 410, 412, 414, and 416, which may be multiple repetitions of the preamble sequence, or may be different preamble sequences linked or associated with each other for random access based on multiple ROs.

[0137] In some aspects, the random access module 1108 is configured to determine a single RA-RNTI for the plurality of ROs based on a predetermined RO in the plurality of ROs, as described above with reference to Figure 6 In some aspects, the random access module 1108 is configured to determine the RA-RNTI for each of the plurality of ROs on a per-RO basis, as described above with reference to Figure 7 In some aspects, the random access module 1108 is configured to respond to a multi-RO based random access preamble, as described above with reference to FIG. 8A to FIG. 8C In some aspects, the random access module 1108 is configured to determine whether to determine a single RA-RNTI for the multiple ROs or to determine a RA-RNTI for each of the multiple ROs based on whether the multiple ROs are associated with a multi-RO based random access or a single-RO based random access, as described above with reference to Fig. 9 In some aspects, the random access module 1108 is configured to determine a single RA-RNTI for multiple ROs based on a function that depends on each of the multiple ROs, as described above with reference to Fig.10 As shown in scheme 1000 discussed.

[0138] As shown, the transceiver 1110 may include a modem subsystem 1112 and an RF unit 1114. The transceiver 1110 may be configured to communicate bidirectionally with other devices such as a UE 115 and / or another core network element. The modem subsystem 1112 may be configured to modulate and / or encode data according to an MCS (e.g., an LDPC decoding scheme, a turbo decoding scheme, a convolutional decoding scheme, a digital beamforming scheme, etc.). The RF unit 1114 may be configured to process (e.g., perform analog-to-digital conversion or digital-to-analog conversion, etc.) modulated / encoded data (e.g., RMSI, OSI, SIB, PRACH configuration, MSG2, MSG4, MSGB) from the modem subsystem 1112 (on outbound transmissions) or from another source (such as a UE 115). The RF unit 1114 may be further configured to perform analog beamforming in conjunction with digital beamforming. Although shown as integrated together in transceiver 1110, modem subsystem 1112 and / or RF unit 1114 may be separate devices that are coupled together at BS 105 to enable BS 105 to communicate with other devices.

[0139] The RF unit 1114 may provide modulated and / or processed data, such as data packets (or, more generally, data messages that may include one or more data packets and other information), to the antenna 1116 for transmission to one or more other devices. According to some aspects of the present disclosure, this may include, for example, sending information to complete attachment to the network and communication with the resident UE 115. The antenna 1116 may further receive data messages sent from other devices and provide received data messages for processing and / or demodulation at the transceiver 1110. The transceiver 1110 may provide demodulated and decoded data (e.g., MSG1, random access preambles based on multiple ROs, random access preambles based on single ROs, MSG3, MSGA) to the random access module 1108 for processing. The antenna 1116 may include multiple antennas with similar or different designs in order to maintain multiple transmission links.

[0140] In some aspects, the transceiver 1110 is configured to communicate with components of the BS 1100 to send a configuration indicating a random access preamble for random access associated with multiple ROs, and receive a random access preamble in one or more of the multiple ROs from a UE (e.g., UE 115 or 1200). The processor 1102 is configured to communicate with components of the BS 1100 to determine one or more radio transceivers. The transceiver 1110 is configured to communicate with components of the BS 1100 to send a RAR message based on one or more determined RA-RNTIs in response to the random access preamble in the RAR window associated with the multiple ROs.

[0141] In one aspect, the BS 1100 may include multiple transceivers 1110 that implement different RATs (e.g., NR and LTE). In one aspect, the BS 1100 may include a single transceiver 1110 that implements multiple RATs (e.g., NR and LTE). In one aspect, the transceiver 1110 may include various components, where different combinations of components may implement different RATs.

[0142] Fig.12 1 is a block diagram of an exemplary UE 1200 according to some aspects of the present disclosure. The UE 1200 may be as described above with respect to Figure 1 UE 115 discussed. As shown, UE 1200 may include a processor 1202, a memory 1204, a random access module 1208, a transceiver 1210 including a modem subsystem 1212 and a radio frequency (RF) unit 1214, and one or more antennas 1216. These elements may communicate with each other directly or indirectly, for example, via one or more buses.

[0143] The processor 1202 may include a central processing unit (CPU), a digital signal processor (DSP), an application specific integrated circuit (ASIC), a controller, a field programmable gate array (FPGA) device, another hardware device, a firmware device, or any combination configured to perform the operations described herein. The processor 1202 may also be implemented as a combination of computing devices, for example, a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors combined with a DSP core, or any other such configuration.

[0144] Memory 1204 may include cache memory (e.g., cache memory of processor 1202), random access memory (RAM), magnetoresistive RAM (MRAM), read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), flash memory, solid-state storage, a hard drive, other forms of volatile and non-volatile memory, or a combination of different types of memory. In one aspect, memory 1204 includes a non-transitory computer-readable medium. Memory 1204 may store instructions 1206 or have instructions 1206 recorded thereon. Instructions 1206 may include instructions that, when executed by processor 1202, cause processor 802 to perform aspects of the present disclosure described herein (e.g., Figure 2 , Figures 3A to 3C , Figures 4 to 7 , FIG. 8A to FIG. 8C , Figures 9 and 10 and Fig.13 Instructions 1206 may also be referred to as program code, which may be broadly interpreted as including instructions as described above with respect to the operation of UE 115. Fig.11 Any type of computer-readable statement in question.

[0145] The random access module 1208 may be implemented via hardware, software, or a combination thereof. For example, the random access module 1208 may be implemented as a processor, circuit, and / or instruction 1206 stored in the memory 1204 and executed by the processor 1202. In some cases, the random access module 1208 may be integrated within the modem subsystem 1212. For example, the random access module 1208 may be implemented by a combination of software components (e.g., executed by a DSP or general purpose processor) and hardware components (e.g., logic gates and circuits) within the modem subsystem 1212.

[0146] The random access module 1208 may be used in various aspects of the present disclosure, for example, Figure 2 , Figures 3A to 3C , Figures 4 to 7 , FIG. 8A to FIG. 8C , Figures 9 and 10 and Fig.13Aspects of the present invention. The random access module 1208 is configured to receive a configuration indicating a random access preamble for random access associated with multiple ROs, send the random access preamble to a BS (e.g., BS 105 or 1100) in one or more of the multiple ROs, determine one or more RA-RNTIs for the multiple ROs, and monitor RAR messages (e.g., MSG2 in four-step random access and MSGB in two-step random access) based on the one or more determined RA-RNTIs during the RAR window associated with the multiple ROs. In some aspects, the random access preamble may include multiple PRACH preamble sequences similar to PRACH preamble sequences 410, 412, 414, and 416, which may be multiple repetitions of the preamble sequence, or may be different preamble sequences linked or associated with each other for random access based on multiple ROs.

[0147] In some aspects, the random access module 1208 is configured to determine a single RA-RNTI for the plurality of ROs based on a predetermined RO in the plurality of ROs, as described above with reference to Figure 6 In some aspects, the random access module 1208 is configured to determine the RA-RNTI for each RO in the plurality of ROs on a per-RO basis, as described above with reference to Figure 7 As shown in the scheme 700 discussed above. In some aspects, the random access module 1208 is configured to monitor RAR messages, as described above with reference to FIG. 8A to FIG. 8C In some aspects, the random access module 1208 is configured to determine whether to determine a single RA-RNTI for the multiple ROs or to determine a RA-RNTI for each of the multiple ROs based on whether the multiple ROs are associated with a multi-RO based random access or a single-RO based random access, as described above with reference to Fig. 9 In some aspects, the random access module 1208 is configured to determine a single RA-RNTI for multiple ROs based on a function that depends on each of the multiple ROs, as described above with reference to Fig.10 As shown in scheme 1000 discussed.

[0148] As shown, the transceiver 1210 may include a modem subsystem 1212 and an RF unit 1214. The transceiver 1210 may be configured to communicate bidirectionally with other devices such as the BS 105. The modem subsystem 1212 may be configured to modulate and / or encode data from the memory 1204 and / or the random access module 1208 according to a modulation and coding scheme (MCS) (e.g., a low-density parity check (LDPC) decoding scheme, a turbo decoding scheme, a convolutional decoding scheme, a digital beamforming scheme, etc.). The RF unit 1214 may be configured to process (e.g., perform analog-to-digital conversion or digital-to-analog conversion, etc.) modulated / encoded data (e.g., MSG1, multi-RO based random access preamble, single-RO based random access preamble, MSG3, MSGA) from the modem subsystem 1212 (on outbound transmissions) or from another source (such as the UE 115 or the BS 105). The RF unit 1214 may further be configured to perform analog beamforming in conjunction with digital beamforming.Although shown as integrated together in the transceiver 1210, the modem subsystem 1212 and the RF unit 1214 may be separate devices coupled together at the UE 115 to enable the UE 115 to communicate with other devices.

[0149] RF unit 1214 can provide modulated and / or processed data, such as data packets (or, more generally, data messages that can include one or more data packets and other information) to antenna 1216 for transmission to one or more other devices. Antenna 1216 can further receive data messages sent from other devices. Antenna 1216 can provide received data messages for processing and / or demodulation at transceiver 1210. Transceiver 1210 can provide demodulated and decoded data (e.g., RMSI, OSI, SIB, PRACH configuration, MSG2, MSG4, MSGB) to random access module 1208 for processing. Antenna 1216 can include multiple antennas with similar or different designs to maintain multiple transmission links. RF unit 1214 can configure antenna 1216.

[0150] In some aspects, the transceiver 1210 is configured to communicate with components of the UE 1200 to receive a configuration indicating a random access preamble for random access associated with multiple ROs, and to send the random access preamble in one or more of the multiple ROs. The processor 1202 is configured to communicate with components of the UE 1200 to determine one or more RA-RNTIs for the multiple ROs. The transceiver 1210 is configured to communicate with components of the UE 1200 to monitor RAR messages in RAR windows associated with the multiple ROs based on the one or more determined RA-RNTIs.

[0151] In one aspect, the UE 1200 may include multiple transceivers 1210 that implement different RATs (e.g., NR and LTE). In one aspect, the UE 1200 may include a single transceiver 1210 that implements multiple RATs (e.g., NR and LTE). In one aspect, the transceiver 1210 may include various components, where different combinations of components may implement different RATs.

[0152] Fig.13 1300 is a flow chart of a wireless communication method 1300 according to some aspects of the present disclosure. Aspects of the method 1300 may be performed by a computing device (e.g., a processor, processing circuitry, and / or other suitable components) of a wireless communication device or other suitable means for performing the steps. For example, a wireless communication device such as UE 115 or 1200 may utilize one or more components (such as a processor 1202, a memory 1204, a random access module 1208, a transceiver 1210, a modem 1212, and one or more antennas 1216) to perform the steps of the method 1300. The method 1300 may be implemented as described above. Figure 2 , FIG. 3A to FIG. 3C , Figures 4 to 7 , FIG. 8A to FIG. 8C and Figures 9 and 10 As shown, method 1300 includes a plurality of enumerated steps, but aspects of method 1300 may include additional steps before, after, and between the enumerated steps. In some aspects, one or more of the enumerated steps may be omitted or performed in a different order.

[0153] At block 1310, the UE (e.g., 115 or 1200) receives a configuration of a random access preamble indicating random access associated with multiple ROs. In some instances, the UE may receive the configuration of a random access preamble indicating random access associated with multiple ROs using one or more components (such as the processor 1202, the memory 1204, the random access module 1208, the transceiver 1210, the modem 1212, and / or one or more antennas 1216).

[0154] In some aspects, the UE may receive a configuration from a SIB broadcast by a BS (e.g., BS 105 and / or 1100). In some aspects, the configuration may indicate a random access preamble pool. In some aspects, a random access preamble pool or a portion of a random access preamble pool may be configured for dedicated multi-RO based random access preamble transmission. The configuration may also indicate an RO associated with the random access preamble pool. In some aspects, each of the multiple ROs may include at least one of different time resources or different frequency resources.

[0155] At block 1320, the UE sends a random access preamble in one or more of the multiple ROs. For example, the UE may randomly select a random access preamble from a random access preamble pool or a portion of a random access preamble pool configured for dedicated multi-RO based random access preamble transmission. The UE may also randomly select multiple ROs from the ROs indicated by the configuration. In some instances, the UE may utilize one or more components (such as a processor 1202, a memory 1204, a random access module 1208, a transceiver 1210, a modem 1212, and / or one or more antennas 1216) to send a random access preamble in one or more of the multiple ROs.

[0156] In some aspects, as part of sending a random access preamble, the UE may send at least one of: sending a first random access preamble (e.g., PRACH preamble sequence portion 1410) in a first RO among the plurality of ROs or sending a second random access preamble (e.g., PRACH preamble sequence portion 2412) in a second RO among the plurality of ROs. In some aspects, as part of sending a random access preamble, the UE may send a first random access preamble in the first RO and a second random access preamble in the second RO, wherein the second random access preamble is at least one of a repetition of the first random access preamble or associated with the first random access preamble.

[0157] At block 1330, the UE determines one or more RA-RNTIs for the plurality of ROs. In some instances, the UE may utilize one or more components (such as the processor 1202, the memory 1204, the random access module 1208, the transceiver 1210, the modem 1212, and / or one or more antennas 1216) to determine one or more RA-RNTIs for the plurality of ROs.

[0158] In some aspects, as part of determining one or more RA-RNTIs for the multiple ROs, the UE may determine a single RA-RNTI for the multiple ROs based on a predetermined RO in the multiple ROs, e.g., as described above with reference to Figure 6 The scheme 600 discussed above. In some aspects, the configuration received at block 1310 may also indicate a predetermined RO. In some aspects, the UE may further determine a single RA-RNTI based on multiple ROs configured for dedicated multi-RO based random access, as described above with reference to Fig. 9 The method 900 is discussed.

[0159] In some aspects, as part of determining one or more RA-RNTIs for the multiple ROs, the UE may determine a RA-RNTI for each of the ROs. In some aspects, the configuration received at block 1310 may also indicate a rule for determining a RA-RNTI for each of the multiple ROs on a per-RO basis. In some aspects, the UE may further determine a RA-RNTI for each of the multiple ROs based on one or more of the multiple ROs configured to be shared between multi-RO based random access and single-RO based random access, as described above with reference to Fig. 9 The method 900 is discussed.

[0160] In some aspects, as part of determining one or more RA-RNTIs for the plurality of ROs, the UE may determine a first RA-RNTI for the plurality of ROs based on a function associated with the plurality of ROs. For example, the function may depend on a starting symbol index for each of the plurality of ROs and / or a frequency resource or RB set index for each of the plurality of ROs, e.g., as described above with reference to Fig.10 The scheme discussed is shown in 1000. In some aspects, the configuration received at block 1310 may also indicate a function associated with the plurality of ROs for determining a first RA-RNTI for the plurality of ROs.

[0161] At block 1340, the UE monitors the RAR message in the RAR window associated with the plurality of ROs based on the one or more determined RA-RNTIs. In some instances, the UE may monitor the RAR message using one or more components such as the processor 1202, the memory 1204, the random access module 1208, the transceiver 1210, the modem 1212, and / or the one or more antennas 1216.

[0162] In some aspects, when the UE determines a single RA-RNTI based on a predetermined RO at block 1330, the UE may monitor RAR messages based on the single RA-RNTI. For example, the UE may monitor a PDCCH candidate having a CRC masked with a single RA-RNTI, for example, based on blind decoding. If the UE successfully decodes a PDCCH candidate having a CRC masked with the RA-RNTI, the UE may continue to receive and decode RAR messages scheduled by the PDCCH candidate, for example, as described above with reference to Figure 3C When the UE determines the first RA-RNTI based on multiple ROs at block 1330, the UE may use the same method as described above. Figure 3C A mechanism similar to the mechanism shown in scheme 340 of the discussion is used to monitor RAR.

[0163] In some aspects, when the UE determines a RO for each of the plurality of ROs at block 1330, the UE may monitor for RAR messages during the RAR window based on at least one of a first RA-RNTI determined for the first RO in response to sending a first random access preamble or a second RA-RNTI determined for the second RO in response to sending a second random access preamble. In some aspects, as part of the monitoring, the UE may receive a first PDCCH that schedules a first RAR message based on the first RA-RNTI, and receive the first RAR message including the first random access preamble based on the first PDCCH. In some aspects, the UE may also receive a second PDCCH that schedules a second RAR message based on the second RA-RNTI, and receive a second RAR message including the second random access preamble based on the second PDCCH, e.g., as described above with reference to Figure 8C In some aspects, the UE may receive the first RAR message and the second RAR message in the same time slot. In some aspects, the UE may receive the first RAR message and the second RAR message in different time slots, for example, as described above with reference to Figure 8B In some aspects, the UE may receive a second PDCCH scheduling a second RAR message based on the second RA-RNTI, and receive a second RAR message not including a second random access preamble based on the second PDCCH, for example, as described above with reference to Fig. 8A The scheme discussed is shown in 802.

[0164] In some aspects, the UE may also determine a starting point of a RAR window (e.g., RAR window 604) for the plurality of ROs based on a predetermined RO among the plurality of ROs. In some aspects, the configuration received at block 1310 may indicate a predetermined RO to be used to determine a starting point of the RAR. In some aspects, the predetermined RO corresponds to an earliest RO among the plurality of ROs, and the UE may determine to start the RAR window after the earliest RO.

[0165] Fig.14 1400 is a flow chart of a wireless communication method 1400 according to some aspects of the present disclosure. Aspects of the method 1400 may be performed by a computing device (e.g., a processor, processing circuitry, and / or other suitable components) of a wireless communication device or other suitable means for performing the steps. For example, a wireless communication device such as BS 105 or 1100 may utilize one or more components (such as a processor 1102, a memory 1104, a random access module 1108, a transceiver 1110, a modem 1112, and one or more antennas 1116) to perform the steps of the method 1400. The method 1400 may be implemented as described above. Figure 2 , FIG. 3A to FIG. 3C , Figures 4 to 7 , FIG. 8A to FIG. 8C and Figures 9 and 10 As shown, method 1400 includes a plurality of enumerated steps, but aspects of method 1400 may include additional steps before, after, and between the enumerated steps. In some aspects, one or more of the enumerated steps may be omitted or performed in a different order.

[0166] At block 1410, a BS (e.g., BS 105 or 1100) transmits a configuration of a random access preamble indicating random access associated with a plurality of ROs. In some instances, the BS may transmit the configuration of a random access preamble indicating random access associated with a plurality of ROs using one or more components (e.g., processor 1102, memory 1104, random access module 1108, transceiver 1110, modem 1112, and / or one or more antennas 1116).

[0167] In some aspects, the BS may broadcast the included SIB. In some aspects, the configuration may indicate a random access preamble pool. In some aspects, the random access preamble pool or a portion of the random access preamble pool may be configured for dedicated multi-RO based random access preamble transmission. The configuration may also indicate the RO associated with the random access preamble pool. In some aspects, each of the multiple ROs may include at least one of different time resources or different frequency resources.

[0168] At block 1420, the BS receives a random access preamble in one or more of the plurality of ROs from a UE (e.g., UE 115 or 1200). In some examples, the BS may receive the random access preamble in one or more of the plurality of ROs using one or more components, such as the processor 1102, the memory 1104, the random access module 1108, the transceiver 1110, the modem 1112, and / or one or more antennas 1116.

[0169] In some aspects, as part of receiving the random access preamble, the BS may receive at least one of a first random access preamble in a first RO of the plurality of ROs (e.g., PRACH preamble sequence portion 1410) or a second random access preamble in a second RO of the plurality of ROs (e.g., PRACH preamble sequence portion 2412). In some aspects, as part of receiving the random access preamble, the BS may receive the first random access preamble in the first RO and the second random access preamble in the second RO, wherein the second random access preamble is at least one of a repetition of the first random access preamble or associated with the first random access preamble.

[0170] At block 1430, the BS determines one or more RA-RNTIs for the plurality of ROs. In some instances, the BS may utilize one or more components (such as the processor 1102, the memory 1104, the random access module 1108, the transceiver 1110, the modem 1112, and / or one or more antennas 1116) to determine one or more RA-RNTIs for the plurality of ROs.

[0171] In some aspects, as part of determining one or more RA-RNTIs for the multiple ROs, the BS may determine a single RA-RNTI for the multiple ROs based on a predetermined RO in the multiple ROs, e.g., as described above with reference to Figure 6 The scheme 600 discussed above. In some aspects, the configuration sent at block 1410 may also indicate a predetermined RO. In some aspects, the BS may further determine a single RA-RNTI based on multiple ROs configured for dedicated multi-RO based random access, as described above with reference to Fig. 9 The method 900 is discussed.

[0172] In some aspects, as part of determining one or more RA-RNTIs for the multiple ROs, the BS may determine to determine a RA-RNTI for each of the ROs. In some aspects, the configuration sent at block 1410 may also indicate a rule for determining the RA-RNTI for each of the multiple ROs on a per-RO basis. In some aspects, the BS may further determine the RA-RNTI for each of the multiple ROs based on one or more of the multiple ROs configured to be shared between multi-RO based random access and single-RO based random access, as described above with reference to Fig. 9 The method 900 is discussed.

[0173] In some aspects, as part of determining one or more RA-RNTIs for the plurality of ROs, the BS may determine a first RA-RNTI for the plurality of ROs based on a function associated with the plurality of ROs. For example, the function may depend on a starting symbol index for each of the plurality of ROs and / or a frequency resource or RB set index for each of the plurality of ROs, e.g., as described above with reference to Fig.10 The scheme discussed is shown in 1000. In some aspects, the configuration sent at block 1410 may also indicate a function associated with the plurality of ROs for determining a first RA-RNTI for the plurality of ROs.

[0174] At block 1440, the BS sends a RAR message based on the one or more determined RA-RNTIs in response to the random access preamble in the RAR window associated with the plurality of ROs. In some instances, the BS may send the RAR message based on the one or more determined RA-RNTIs using one or more components such as the processor 1102, the memory 1104, the random access module 1108, the transceiver 1110, the modem 1112, and / or the one or more antennas 1116.

[0175] In some aspects, when the BS determines a single RA-RNTI based on a predetermined RO at block 1430, in response to receiving at least one of a first random access preamble in a first RO or a second random access preamble in a second RO and based on the single RA-RNTI, the UE may, for example, use the same method as described above with reference to Figure 3C A mechanism similar to the mechanism in the discussed scheme 340 is used to send the PDCCH that schedules the RAR message.

[0176] In some aspects, when the BS determines an RO for each of the plurality of ROs at block 1430, in response to receiving a first random access preamble in a first RO, the BS may send a first PDCCH scheduling a first RAR message based on a first RA-RNTI determined for the first RO, and send the first RAR message including the first random access preamble based on the first PDCCH. In response to receiving a second random access preamble in a second RO, the BS may also send a second PDCCH scheduling a second RAR message based on a second RA-RNTI determined for the second RO, the second RAR message including the second random access preamble, based on the second PDCCH, e.g., as described above with reference to Figure 8C In some aspects, the BS may send the first RAR message and the second RAR message in the same time slot. In some aspects, the BS may send the first RAR message and the second RAR message in different time slots, for example, as described above with reference to Figure 8B In some aspects, when the BS also receives a second random access preamble and a random access preamble based on single RO access in the second RO at block 1420, the BS may also send a second RAR message based on a second RA-RNTI associated with the second RO in the same time slot as the first RAR message, wherein the second RAR message may include a random access preamble based on single RO access, but may not include the second random access preamble, for example, as described above with reference to Fig. 8A The scheme discussed is shown in 802.

[0177] In some aspects, the BS may also determine a starting point of a RAR window (e.g., RAR window 604) for the plurality of ROs based on a predetermined RO among the plurality of ROs. In some aspects, the BS may also indicate a predetermined RO among the plurality of ROs for use in determining the starting point of the RAR window in the configuration sent at block 1410. In some aspects, the predetermined RO may correspond to an earliest RO among the plurality of ROs.

[0178] Information and signals may be represented using a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips referenced throughout the above description may be represented by voltage, current, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.

[0179] The various illustrative blocks and modules described in conjunction with the disclosure herein may be implemented or executed with a general purpose processor, a DSP, an ASIC, an FPGA or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. The general purpose processor may be a microprocessor, but in an alternative, the processor may be any conventional processor, controller, microcontroller, or state machine. The processor may also be implemented as a combination of computing devices (e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration).

[0180] The functions described herein can be implemented in hardware, software executed by a processor, firmware, or any combination thereof. If implemented in software executed by a processor, these functions can be stored or sent as one or more instructions or codes on a computer-readable medium. Other examples and implementations are within the scope of the present disclosure and the appended claims. For example, due to the nature of software, the above functions can be implemented using software executed by a processor, hardware, firmware, hard wiring, or any combination of these. The features that implement the functions can also be physically located in different locations, including being distributed so that some functions are implemented in different physical locations. In addition, as used herein, including in the claims, the "or" used in a list of items (e.g., a list of items beginning with phrases such as "at least one" or "one or more") indicates a list of inclusions, so that, for example, a list of [at least one of A, B, or C] represents A or B or C or AB or AC or BC or ABC (i.e. A and B and C).

[0181] As some skilled in the art will now appreciate, and depending on the specific application at hand, many modifications, substitutions and changes may be made in and to the materials, devices, configurations and methods of use of the apparatus of the present disclosure without departing from the spirit and scope of the present disclosure. In view of this, the scope of the present disclosure should not be limited to the scope of the specific embodiments illustrated and described herein, as they are merely examples thereof, but should correspond fully to the scope of the appended claims and their functional equivalents.

Claims

1. A method of wireless communication performed by a user equipment (UE), the method comprising: receiving a configuration indicating a random access preamble for random access associated with a plurality of random access opportunities (ROs); sending the random access preamble in one or more ROs of the plurality of ROs; determining a single random access radio network temporary identifier (RA-RNTI) of the plurality of ROs based on predetermined ones of the plurality of ROs, wherein respective ones of the plurality of ROs include different frequency resources; and Random access response (RAR) messages are monitored based on a single determined RA-RNTI in a RAR window associated with the plurality of ROs.

2. The method of claim 1 , wherein sending the random access preamble comprises: At least one of the following is transmitted: a first random access preamble is transmitted in a first RO among the plurality of ROs or a second random access preamble is transmitted in a second RO among the plurality of ROs.

3. The method according to claim 2, wherein sending the random access preamble further comprises: The first random access preamble is sent in the first RO and the second random access preamble is sent in the second RO, wherein the second random access preamble is at least one of: the second random access preamble is a repetition of the first random access preamble or the second random access preamble is associated with the first random access preamble.

4. The method of claim 1 , wherein determining the single RA-RNTI further comprises: A single RA-RNTI is determined further based on the multiple ROs being associated with a dedicated multi-RO based random access.

5. The method of claim 1 , wherein receiving the configuration comprises: A configuration of a predetermined RO is received further indicating determination of the single RA-RNTI for the plurality of ROs.

6. The method according to any one of claims 1 to 3, further comprising: Starting points of the RAR windows of the plurality of ROs are determined based on a predetermined RO among the plurality of ROs.

7. The method of claim 6, wherein receiving the configuration further comprises: A configuration is received further indicating the predetermined RO among the plurality of ROs for determining the starting point of the RAR window.

8. The method of claim 6, wherein the predetermined RO corresponds to an earliest RO among the plurality of ROs.

9. The method of claim 1 , wherein determining the single RA-RNTI comprises: A first RA-RNTI of the plurality of ROs is determined based on a function associated with the plurality of ROs.

10. The method of claim 9, wherein receiving the configuration further comprises: A configuration of a function associated with the plurality of ROs is received that further indicates determination of the first RA-RNTI for the plurality of ROs.

11. The method according to any one of claims 1 to 3, wherein each RO of the plurality of ROs comprises a different time resource.

12. A user equipment (UE), comprising: Transceiver; as well as a processor, the processor being in communication with the transceiver, wherein the UE is configured to: receiving a configuration indicating a random access preamble for random access associated with a plurality of random access opportunities (ROs); as well as sending the random access preamble in one or more ROs of the plurality of ROs; determining a single random access radio network temporary identifier (RA-RNTI) of the plurality of ROs based on predetermined ones of the plurality of ROs, wherein respective ones of the plurality of ROs include different frequency resources; and Random access response (RAR) messages are monitored based on a single determined RA-RNTI in a RAR window associated with the plurality of ROs.

13. A user equipment (UE), comprising: means for receiving a configuration indicating a random access preamble for random access associated with a plurality of random access opportunities (ROs); means for transmitting the random access preamble in one or more ROs of the plurality of ROs; means for determining a single random access radio network temporary identifier (RA-RNTI) for the plurality of ROs based on predetermined ones of the plurality of ROs, wherein respective ones of the plurality of ROs include different frequency resources; as well as Means for monitoring a random access response (RAR) message based on a single determined RA-RNTI within a RAR window associated with the plurality of ROs.

14. The UE according to claim 13, wherein the means for sending the random access preamble is further configured to: At least one of: sending a first random access preamble in a first RO among the plurality of ROs or sending a second random access preamble in a second RO among the plurality of ROs.

15. The UE according to claim 14, wherein the means for sending the random access preamble is further configured to: The first random access preamble is sent in the first RO and the second random access preamble is sent in the second RO, wherein the second random access preamble is at least one of: the second random access preamble is a repetition of the first random access preamble or the second random access preamble is associated with the first random access preamble.

16. The UE according to claim 13, wherein the means for determining the single RA-RNTI is configured to: A single RA-RNTI is determined further based on the multiple ROs being associated with a dedicated multi-RO based random access.

17. The UE according to claim 13, wherein the means for receiving the configuration is configured to: A configuration of a predetermined RO is received further indicating determination of the single RA-RNTI for the plurality of ROs.

18. The UE according to any one of claims 13 to 15, further comprising: means for determining a starting point of the RAR window of the plurality of ROs based on a predetermined RO among the plurality of ROs.

19. The UE according to claim 13, wherein the means for determining the single RA-RNTI is configured to: A first RA-RNTI of the plurality of ROs is determined based on a function associated with the plurality of ROs.

20. The UE according to claim 19, wherein the means for receiving the configuration is configured to: A configuration of a function associated with the plurality of ROs is received that further indicates determination of the first RA-RNTI for the plurality of ROs.

21. The UE according to any one of claims 13 to 15, wherein each of the plurality of ROs comprises a different time resource.

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