Control of random access response supervision for wireless networks

Abstract

According to an example embodiment, an apparatus includes at least one processor and at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus to at least: obtain a message instructing the apparatus to trigger or initiate a random access (RA) procedure to access a cell of a network device, the message indicating whether the apparatus will monitor for or receive a random access response (RAR) within an RA response window during the triggered random access procedure; and determine, based on the instruction, whether to monitor for or receive a RAR within the RA response window.

Description

[Technical Field]

[0001] The present description relates to wireless communications. [Background technology]

[0002] A communication system may be a facility that enables communication between two or more nodes or devices, such as fixed or mobile communication devices. Signals may be carried over wired or wireless carriers.

[0003] An example of a cellular communication system is the 3rd Generation Partnership Project (3GPP). rd The architecture is standardized by the Universal Mobile Telecommunications System (UMTS) Generation Partnership Project. Recent developments in this field are often referred to as the long-term evolution (LTE) of Universal Mobile Telecommunications System (UMTS) radio access technology. E-UTRA (evolved UMTS Terrestrial Radio Access) is the air interface of 3GPP's Long Term Evolution (LTE) upgrade path for mobile networks. In LTE, base stations or access points (APs), called enhanced nodes (eNBs), provide wireless access within a coverage area or cell. In LTE, mobile devices or mobile stations are called user equipments (UEs). LTE has included several improvements or developments. LTE features continue to be improved. Summary of the Invention [Problem to be solved by the invention]

[0004] The development of 5G New Radio (NR) is part of the ongoing evolution of mobile broadband to meet 5G requirements, similar to the evolution of previous 3G and 4G wireless networks. Additionally, 5G targets emerging use cases in addition to mobile broadband. The goal of 5G is to achieve significant improvements in radio performance, which may include new levels of data rate, latency, reliability, and security. 5G NR may be scaled to efficiently connect the massive Internet of Things (IoT) and provide new types of mission-critical services. For example, ultra-reliable and low-latency communications (URLLC) devices may require high reliability and extremely low latency. [Means for solving the problem]

[0005] According to an example embodiment, an apparatus includes at least one processor and at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus to at least: obtain a message instructing the apparatus to trigger or initiate a random access (RA) procedure to access a cell of a network device, the message indicating whether the apparatus will monitor or receive a random access response (RAR) within an RA response window during the triggered random access procedure; and determine, based on the instruction, whether to monitor for an RAR within the RA response window.

[0006] According to an example embodiment, a method may include obtaining a message instructing a device to trigger or initiate a random access (RA) procedure to access a cell of a network device, the message indicating whether the device will monitor for or receive a random access response (RAR) within an RA response window during the triggered random access procedure, and determining whether to monitor for an RAR within the RA response window based on the instruction.

[0007] According to an example embodiment, the apparatus may include means for obtaining, by the user device, a message instructing the user device to trigger or initiate a random access (RA) procedure to access a cell of the network device, the message indicating whether the apparatus is to monitor for or receive a random access response (RAR) within an RA response window during the triggered random access procedure, and means for determining, by the user device, based on the instruction, whether to monitor for an RAR within the RA response window.

[0008] According to an example embodiment, a non-transitory computer-readable storage medium includes stored instructions that, when executed by at least one processor, are configured to cause a computing system to: obtain a message instructing a device to trigger or initiate a random access (RA) procedure to access a cell of a network device, the message indicating whether the device will monitor for or receive a random access response (RAR) within an RA response window during the triggered random access procedure; and determine, based on the instruction, whether to monitor for a RAR within the RA response window.

[0009] The details of one or more example embodiments are set forth in the accompanying drawings and the description below. Other features will be apparent from the description and drawings, and from the claims. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a block diagram of a wireless network according to an example embodiment. [Figure 2A] 1 illustrates the operation of a four-step random access (RACH) procedure, in accordance with an example embodiment. [Figure 2B] 1 illustrates the operation of a two-step random access (RACH) procedure, in accordance with an example embodiment. [Figure 3] 1 is a diagram illustrating multiple candidate target cells, according to an example embodiment. [Figure 4] 10 is a diagram illustrating a random access response window, according to an example embodiment. [Figure 5] 1 is a flowchart illustrating the operation of a user device (or UE), according to an example embodiment. [Figure 6] 1 is a block diagram of a radio station or wireless node (e.g., a network node, a network device, a user node, a user device, a UE, a relay node, or other node). DETAILED DESCRIPTION OF THE INVENTION

[0011] Figure 1 is a block diagram of a wireless network 130 according to an example embodiment. In the wireless network 130 of Figure 1, user devices 131, 132, 133, and 135, which may also be referred to as mobile stations (MS) or user equipment (UE), may be connected to (and communicate with) a base station (BS) 134, which may also be referred to as an access point (AP), enhanced Node B (eNB), gNB, or network node. The terms user device and user equipment (UE) may be used interchangeably. A BS may include a radio access network (RAN) node or may be referred to as a RAN node, and may include a portion of a BS or a portion of a RAN node (e.g., a centralized unit (CU) and / or a distributed unit (DU), etc., in the case of a split BS or split gNB). At least a portion of the functionality of a BS (e.g., access point (AP), base station (BS) or (e)Node B (eNB), gNB, RAN node) may be performed by any node, server, or host that may be operatively coupled to a transceiver, such as a remote radio head. BS (or AP) 134 provides wireless coverage within cell 136, which includes user devices (or UEs) 131, 132, 133, and 135. While only four user devices (or UEs) are shown connected to or attached to BS 134, any number of user devices may be provided. BS 134 is also connected to core network 150 via S1 interface 151. This is just one simple example of a wireless network, and other wireless networks may be used.

[0012] A base station (e.g., BS 134, etc.) is an example of a radio access network (RAN) node in a wireless network. A BS (or RAN node) may be or include (or alternatively may be considered to be), for example, an access point (AP), a gNB, an eNB, or a portion thereof (e.g., a centralized unit (CU) and / or a distributed unit (DU) in the case of a split BS or split gNB), or other network node.

[0013] According to one example, a BS node (e.g., BS, eNB, gNB, CU / DU, ...) or a radio access network (RAN) may be part of a mobile telecommunications system. The RAN (Radio Access Network) may include one or more BS or RAN nodes implementing radio access technology, for example, to enable one or more UEs to access a network or a core network. Thus, for example, a RAN (RAN node such as a BS or gNB) may reside between one or more user devices or UEs and the core network. According to example embodiments, each RAN node (e.g., BS, eNB, gNB, CU / DU, ...) or BS may provide one or more wireless communication services to one or more UEs or user devices, for example, to enable the UEs to wirelessly access the network via the RAN node. Each RAN node or BS may perform or provide wireless communication services, such as, for example, enabling the UEs or user devices to establish a wireless connection with the RAN node and transmitting and / or receiving data to one or more of the UEs. For example, after establishing a connection with a UE, a RAN node or network node (e.g., BS, eNB, gNB, CU / DU, ...) may forward data received from the network or core network to the UE and / or forward data received from the UE to the network or core network. The RAN node or network node (e.g., BS, eNB, gNB, CU / DU, ...) may perform a wide variety of other wireless functions or services, such as broadcasting control information (e.g., system information or on-demand system information, etc.) to the UE, paging the UE when there is data to be delivered to the UE, assisting in handover of the UE between cells, scheduling resources for uplink data transmission from the UE and downlink data transmission to the UE, sending control information to configure one or more UEs, etc.There are several examples of one or more functions that a RAN node or a BS may perform.

[0014] A user device or user node (e.g., user terminal, user equipment (UE), mobile terminal, handheld wireless device) may refer to a portable computing device, including a wireless mobile communication device that operates with or without a subscriber identification module (SIM), and examples include, but are not limited to, types of devices such as mobile stations (MS), mobile phones, cell phones, smartphones, personal digital assistants (PDAs), handsets, devices that use wireless modems (e.g., alarm or measurement devices), laptop and / or touchscreen computers, tablets, phablets, game consoles, notebooks, vehicles, sensors, and multimedia devices, or any other wireless device. It should be understood that a user device may also be (or include) an almost exclusively uplink-only device, an example of which is a camera or video camera that captures images or video clips into the network. Also, a user node may include user equipment (UE), user device, user terminal, mobile terminal, mobile station, mobile node, subscriber device, subscriber node, subscriber terminal, or other user node. For example, a user node may be used for wireless communication with one or more network nodes (e.g., gNB, eNB, BS, AP, CU, DU, CU / DU) and / or with one or more other user nodes, regardless of technology or radio access technology (RAT).In LTE (as an example), the core network 150 may be referred to as an Evolved Packet Core (EPC), which may include a mobility management entity (MME) that may handle or assist mobility / handover of user devices between BSs, one or more gateways that may forward data and control signals between the BSs and a packet data network or the Internet, and other control functions or blocks. Other types of wireless networks, such as 5G (sometimes referred to as New Radio (NR)), may also include a core network.

[0015] Additionally, the techniques described herein may be applied to various types of user devices or data service types, or to user devices on which multiple applications, which may be different data service types, can be executed. New Radio (5G) developments may support multiple different applications or multiple different data service types, examples of which include machine type communications (MTC), enhanced machine type communications (eMTC), Internet of Things (IoT) and / or narrowband IoT user devices, enhanced mobile broadband (eMBB), and ultra-reliable and low-latency communications (URLLC). Many of these new 5G (NR)-related applications may generally require higher performance than previous wireless networks.

[0016] The IoT may refer to a growing group of objects that may include internet or network connectivity, allowing them to send information to and receive information from other network devices. For example, many sensor-type applications or devices can monitor physical conditions or states and send reports to servers or other network devices, e.g., when an event occurs. Machine-type communication (MTC or machine-to-machine communication) may be characterized, e.g., by the fully automatic generation, exchange, processing, and action of data between intelligent machines, with or without human intervention. Enhanced Multimedia Broadcasting (eMBB) may support data rates much higher than those currently available with LTE.

[0017] Ultra-reliable and low-latency communications (URLLC) is a new type of data service or new usage scenario that can be supported for new radio (5G) systems. URLLC enables emerging applications and services such as industrial automation, autonomous driving, vehicle safety, and e-health services. 3GPP, for example, is working on the 10 ー5 The goal is to provide a reliable connection with a block error rate (BLER) of 1 ms and a U-plane (user / data plane) latency of up to 1 ms. Thus, for example, a URLLC user device / UE may require low latency (with or without a simultaneous requirement for high reliability) in addition to a significantly lower block error rate than other types of user devices / UEs. Thus, for example, a URLLC UE (or a URLLC application on a UE) may require much lower latency compared to an eMBB UE (or an eMBB application running on a UE).

[0018] The techniques described herein may be applied to a wide variety of wireless technologies or wireless networks, such as LTE, LTE-A, 5G (New Radio (NR)), centimeter-wave and / or millimeter-wave band networks, IoT, MTC, eMTC, eMBB, URLLC, etc., or any other wireless network or wireless technology. These example networks, technologies, or types of data services are provided merely as examples.

[0019] In at least some cases, a UE may be in one of multiple states (e.g., one of three Radio Resource Control (RRC) states) with respect to a network node or a gNB. In the idle state (RRC Idle), typically, the RRC context stored in the Radio Access Network (RAN) node (e.g., a gNB) or network node, or in the UE (the RRC context may include information or parameters necessary for communication between the UE and the gNB / network node), is absent (or limited), and the UE does not belong to (or is not connected to) a particular cell. From the core network's perspective, an idle UE is in an idle (CM_Idle) state. When a UE is in the idle state, typically, no data transfer can occur between the UE and a network node (e.g., a gNB) because the UE sleeps most of the time (in a low power state) to conserve power. In the idle state, the UE typically can wake up periodically to receive paging messages from the network.

[0020] A UE can transition from an idle state (e.g., RRC Idle) to a connected state (e.g., RRC Connected state in which the UE is connected to the network node) by performing a random access (RACH) procedure with a gNB or a network node. As part of the RACH procedure, both the UE and the network node (e.g., gNB) may obtain context, e.g., communication parameters necessary to enable UE-gNB communication. As an example communication parameter, the UE may obtain, e.g., a timing advance as part of the RACH procedure with the gNB or network node to enable the UE to perform uplink transmissions to the gNB. The UE may also obtain a UE identity from the network, such as a cell-radio network temporary identifier (C-RNTI), which may be used by the UE for communication or signaling with the network or gNB. In the connected state (e.g., RRC Connected) to a cell (or gNB or DU), the UE is connected to the gNB or network node, and the UE may receive data and transmit data (e.g., based on the reception of an uplink grant).

[0021] 2A illustrates the operation of a four-step random access (RACH) procedure according to an example embodiment. When the RACH procedure is triggered (caused to be performed by the UE), the UE transmits a random access (RACH) preamble on the random access (RACH) channel (step 1) or Msg1 (Message 1). Depending on the size of Msg3 (Message 3) and based on the UE's channel conditions, there are different groups of preambles that are defined or configured. The UE obtains information on how to access the RACH channel from system information block 1 (SIB1), which is broadcast in system information (SI) from the gNB. After receiving Message 1 (Random Access Preamble from the UE), the gNB determines the reception timing of the received random access preamble. Based on the receive timing of the received preamble (in the absence of collisions with other UEs), the gNB determines a timing advance (or TA or timing advance command) and adjusts the timing of the UE uplink frame to match the downlink frame (and to match the receive timing of the uplink with other UE uplink frames). Because each UE may be located at a different location, each UE may have a different radio propagation delay and therefore may have a different or specific timing advance with respect to the gNB.

[0022] As shown in FIG. 2A, in step 2 (Msg2 or Message 2), the gNB responds to the UE with a random access response (RAR), which may include an index to the received random access (or RACH) preamble (an index or identifier of the random access preamble resource) (also known as a RAPID or random access preamble identifier) ​​(or an identifier of the received random access (or RACH) preamble), a timing advance (TA, or timing advance command), a temporary cell-radio network temporary identifier (TC-RNTI) assigned to the UE, and an uplink (UL) grant (e.g., including scheduling information and / or information indicating resources to be used for the UL transmission) used by the UE for the uplink transmission of Message 3 (Msg3). Upon receiving the RAR message (Msg2), the UE can send its first uplink transmission (Msg3 or Message 3) to the network. The size of the transmission of Msg3 depends on the grant (Msg2 or Message 2) received in step 2. Step 4 (Msg4 or Message 4) may include the transmission of a DL message from the gNB to the UE, including a contention resolution phase. After the UE has attached to the gNB (e.g., after the random access procedure is completed), the UE may receive an updated timing advance (TA) value or TA command from the serving gNB or serving cell.

[0023] Furthermore, as an alternative RACH procedure, a two-step RACH (random access) procedure may be used to provide a faster random access procedure. Figure 2B is a diagram illustrating the operation of a two-step random access (RACH) procedure according to an example embodiment. In message A (MsgA), a UE may send a message including the contents of both Msg1 and Msg3 as the first message (MsgA) of the two-step RACH procedure. Also, for example, a network node or gNB may send Msg2 and Msg4 as the second message (or MsgB or message B) of the two-step RACH procedure.

[0024] A timing advance group (TAG) may include one or more serving cells with the same uplink TA and the same downlink timing reference cell. Each TAG may include one serving cell with a configured uplink, and the mapping of each serving cell to a TAG may be configured by the gNB, for example, via a Radio Resource Control (RRC) message. The TAG field in the MAC CE may refer to a TAG identifier (or TAG ID) specified in the RRC message.

[0025] The gNB or network node may trigger or cause the UE to perform a random access procedure to a particular cell by sending a physical downlink control channel (PDCCH) command. The PDCCH command may include, for example, the physical cell identity (PCI) of the cell from which the UE should perform random access and a random access preamble resource identifier (e.g., a random access preamble index or identifier) ​​that the UE should use to perform random access to the indicated cell (e.g., to send as Msg1 to the cell).

[0026] The UE may perform a cell change from one cell to another. The UE may have multiple candidate target cells (to which the UE can perform a cell change or handover), and a cell change (or handover) may be performed to these candidate target cells. Figure 3 is a diagram illustrating multiple candidate target cells, according to an example embodiment. A UE 310 may be served by a serving cell (e.g., a serving cell with a physical cell identity (PCI) of PCI_1), but may have multiple candidate target cells, including candidate target cells with physical cell identities (PCIs) PCI_2, PCI_3, ... PCI_N.

[0027] However, after a cell change of the UE to the target cell is triggered, a delay in uplink communications may typically occur while the UE performs random access to the target cell and acquires an uplink timing advance (TA). FIG. 4 is a diagram illustrating a random access response window according to an example embodiment. At 1, the UE may transmit a random access preamble to the target cell. At 2, the gNB may transmit message 2 including a random access response (RAR) that includes the UE's TA value. The UE may typically receive the RAR during the random access response window (3). The UE typically does not transmit or receive during the random access response (RAR) window because it detects, monitors, and / or receives the RAR during the RAR window (3). However, if the UE is performing random access to each of the candidate target cells to receive a TA value from each of the candidate target cells, this may cause significant overhead to the UE and may shorten the period during which the UE can otherwise transmit or receive data or other signals.

[0028] Various example techniques and / or embodiments are disclosed that can enable a UE to determine whether to monitor or receive a random access response from a cell (e.g., a candidate target cell). For example, the UE may obtain (e.g., receive) a message (e.g., downlink control information (DCI) and / or a PDCCH command) from a network device or network node (e.g., a gNB) that instructs the UE to trigger or initiate a random access (RA) procedure to access the network device's cell. The message may indicate whether the UE will monitor or receive a random access response (RAR) within an RA response window during the triggered random access procedure. For example, if the message indicates that the UE will monitor or receive an RA response within the RA response window, the UE will monitor and receive (or attempt to receive) an RAR within the RA response window of the triggered random access response procedure. If an RAR is monitored and received by the UE, the UE may send an indication to the network device or serving cell indicating that a random access procedure has been performed (and / or a TA value has been received from) the cell (e.g., using the candidate target cell). Otherwise, if the message (e.g., DCI and / or PDCCH command) indicates that the UE is not required to monitor or receive an RA response within the RA response window of the triggered random access procedure, the UE may (or may omit) monitoring and / or receiving a random access response (RAR) for the triggered random access procedure, and the UE may determine or assume that the triggered random access procedure has completed successfully after an RA preamble transmission from the UE to the cell of the network device for the triggered random access procedure.

[0029] In example embodiments, a message (e.g., a DCI and / or PDCCH command) obtained by the UE may explicitly or implicitly indicate whether the UE monitors for or receives a random access response (RAR) within an RA response window during a triggered random access procedure. For example, the message (e.g., a DCI and / or PDCCH command) may include a field (e.g., a bit, a set of bits, a codepoint value, or a table lookup value) set to a value to explicitly indicate to the UE whether the UE monitors for or receives a random access response (RAR) within an RA response window during a triggered random access procedure. Thus, the message may include a field to explicitly indicate whether the UE monitors for or receives a random access response (RAR) within an RA response window during a triggered random access procedure. As an example of an explicit indication, a field in the message may be set to a first value to indicate that the UE should monitor for or receive a RAR for the triggered RA procedure, while the field may be set to a second value to indicate that the UE should neither monitor nor receive a RAR for the triggered RA procedure.

[0030] In some embodiments, the UE may monitor (or be configured to monitor) the RAR of a triggered RA procedure and may be further configured to communicate with the cell that triggered the procedure upon successful completion of the procedure (e.g., indicating success and / or the TA value obtained).

[0031] In some example embodiments, the UE may receive explicit instructions (DCI and / or PDCCH commands) indicating whether the UE should / is required to monitor for a response to the transmission of a preamble. In one example, the UE may receive instructions to monitor or receive DCI (sent in response to an RA preamble and may schedule an RAR message), but is not required to receive RAR, or the UE does not expect to receive RAR, or the UE does not expect to be scheduled by a PDSCH (Physical Downlink Shared Channel) that provides DCI and RAR.

[0032] Alternatively, as an example of an implicit indication of whether the UE should monitor or receive a RAR, the message (e.g., DCI and / or PDCCH command) may include or indicate random access preamble resources associated with monitoring or receiving a random access response (RAR) within an RA response window during a triggered random access procedure (e.g., the message may indicate an RA preamble identifier or an RA preamble index), or the message may indicate random access preamble resources associated with not monitoring or receiving a random access response (RAR) within the RA response window during a triggered random access procedure (e.g., the RA preamble identifier or the RA preamble index). For example, a first list of random access preamble resources may be associated with monitoring or receiving a random access response (RAR) within the RA response window during a triggered random access procedure, and a second list of random access preamble resources may be associated with not monitoring or receiving a random access response (RAR) within the RA response window during a triggered random access procedure. Thus, the message may indicate a first random access (RA) preamble resource from a first list of random access preambles to (e.g., implicitly) indicate to the UE that the UE will (or should) monitor or receive a random access response (RAR) within the RA response window during the triggered random access procedure. Alternatively, the message may indicate a second random access (RA) preamble resource from a second list of random access preambles to (e.g., implicitly) indicate to the UE that the UE will (or should) monitor or receive a random access response (RAR) within the RA response window during the triggered random access procedure.Also, according to example embodiments, in cases such as when the UE does not monitor or receive an RA response from a cell (e.g., from a candidate target cell or a serving cell), such candidate target cell may receive an RA preamble transmitted by the UE (e.g., as message 1 of the partial random access procedure), and the candidate cell may determine or estimate a timing advance (TA) value or TA command for the UE and forward such TA value to a network device or a serving (or source) cell. The UE's network device (network node) or serving or source cell may receive TA values ​​for the UE from one or more (e.g., multiple) candidate target cells (e.g., based on the RA preamble transmitted by the UE to each of these candidate target cells), and the network device or serving (or source) cell may forward these one or more TA values ​​(estimated for the UE) to the UE. For example, at least in some cases, this may provide a more efficient technique for a UE to obtain TA values ​​from (or for) multiple candidate target cells without necessarily requiring the UE to perform a full random access procedure (including monitoring and receiving TA values ​​from each of the candidate target cells).

[0033] 5 is a flowchart illustrating the operation of a user device (or UE) according to an example embodiment. Operation 510 includes obtaining, by the user device, a message instructing the user device to trigger or initiate a random access (RA) procedure to access a cell of a network device, the message indicating whether the device should monitor for or receive a random access response (RAR) within an RA response window during the triggered random access procedure. Operation 520 includes determining, by the user device, based on the instruction, whether to monitor for an RAR within the RA response window.

[0034] For the method of FIG. 5, the message may include downlink control information (DCI) received over a physical downlink control channel (PDCCH).

[0035] With respect to the method of FIG. 5, the message may include a field that triggers or causes a physical downlink control channel (PDCCH) command indicating whether the device monitors or receives an RAR response within the RA response window during a triggered random access procedure initiated via the PDCCH command. In one example, the PDCCH command may include one or more preamble indices (or one or more preamble index+PCI pairs). In a further example, one PDCCH command (DCI message) may trigger one or more RA procedures, where the UE may be indicated whether to monitor for an RA response (can receive an indication of whether to monitor for an RA response). The indication of whether to monitor for an RA response may be indicated for each preamble index (or preamble index+PCI pair). Alternatively, the indication of whether to monitor may apply to all preamble indices (or preamble index+PCI) listed in the PDCCH command. Upon receiving a PDCCH command containing a list of one or more preamble index values, the UE may trigger one or more RA procedures (and may complete the procedures as described herein) to transmit an RA preamble for each of the RA preamble indices listed in the PDCCH command. The UE may initiate / trigger the RA procedures in the order of the listed preamble indices, or in an order selected (or random) by the UE. In one example, the PDCCH command may include a pointer, e.g., a bit value associated with a configured set / list of pre-configured ra preamble index values ​​(+PCI) that are triggered by the PDCCH command. This list may be configured, for example, using RRC (or RRC+MAC CE, or MAC CE) signaling.

[0036] In some examples, the PCI value listed in the PDCCH command (or in the RRC configuration associated with the PDCCH command) may be a re-indexed value of the full PCI value. For example, the actual PCI value (e.g., 10 bits) may be mapped to a shorter re-indexed PCI value, and this re-indexed value may be signaled using, for example, a fewer number of bits (e.g., 3 bits). This, for example, saves on the amount of signaled bits.

[0037] 5, the field may include at least one of 1 bit, N bits, a code point value, or a value used as a table lookup, where N is a positive integer. For the method of FIG. 5, the method may include determining or assuming, by the device, that the triggered random access procedure has completed successfully after an RA preamble transmission from the device to the cell of the network device for the triggered random access procedure, if the message indicates that the device does not monitor or receive an RAR within an RAR response (RAR) window during the triggered random access procedure.

[0038] With respect to the method of FIG. 5, the method may include determining or assuming that the triggered random access procedure has completed successfully after a random access (RA) preamble transmission corresponding to the random access preamble resource from the apparatus to a cell of the network device for the triggered random access procedure, if the instruction indicates that the random access preamble resource is configured not to be associated with an RAR.

[0039] With respect to the method of FIG. 5, the method may include obtaining a downlink reference signal (DL RS) indicated in the PDCCH command (the DL RS may be obtained / determined by association with the RA preamble), and determining, based on the DL RS, whether a random access response (RAR) is configured to be monitored or received by the device (or UE) within an RAR window of the triggered random access procedure.

[0040] With respect to the method of FIG. 5, the method may include storing resources associated with a downlink reference signal (DL) RS in a list of downlink resources.

[0041] With respect to the method of FIG. 5, the list of downlink resources may include one or more timing advance (TA) references or values.

[0042] For the method of FIG. 5, the size of the list of downlink resources is predefined or configured by the network device.

[0043] For the method of FIG. 5, each downlink resource list is associated with a corresponding physical cell identity (PCI) value.

[0044] With respect to the method of FIG. 5, the method may include associating each list of downlink resources with a corresponding validity timer.

[0045] For the method of FIG. 5, the maximum value of each of the validity timers is predefined or configured by the network device.

[0046] For the method of FIG. 5, after successful completion of the triggered random access procedure, each validity timer is started.

[0047] With respect to the method of FIG. 5, the method may include, if the indication indicates that the device does not monitor or receive an RAR within an RAR window of the triggered random access procedure, obtaining a timing advance (TA) value associated with at least one downlink resource in the list of downlink resources for the triggered random access procedure.

[0048] For the method of FIG. 5, the obtained timing advance (TA) value is different from the TA value currently in use in the network device's cell for the triggered random access procedure.

[0049] With respect to the method of FIG. 5, the method may include, upon obtaining a timing advance (TA) value, performing one or more subsequent uplink transmissions to the cell of the network device according to the obtained TA value.

[0050] With respect to the method of FIG. 5, the method may include indicating successful completion of the triggered random access procedure to a cell of the network device if the indication indicates that downlink control information (DCI) triggers or causes a PDCCH command and that a target downlink reference signal (DL RS) of the random access (RA) preamble transmission is associated with a different cell of the network device.

[0051] With respect to the method of FIG. 5, the method may include determining whether to report successful completion of the triggered random access procedure to a cell of the network device when the physical downlink control channel (PDCCH) command indicates that the device monitors or receives a random access response (RAR) of the random access (RA) preamble transmission.

[0052] With respect to the method of FIG. 5, the method may include indicating one or more physical cell identities (PCIs) to a cell of the network device where at least one of the RA procedures triggered by the PDCCH command is completed or a timing advance (TA) value is received.

[0053] With respect to the method of FIG. 5, one or more physical cell identities (PCIs) are indicated via a media access control-control element (MAC-CE).

[0054] With respect to the method of FIG. 5, the message may include a random access preamble resource and a physical downlink control channel (PDCCH) command instructing the device to perform a triggered random access procedure, the PDCCH command explicitly or implicitly indicating whether the device should monitor or receive a random access response (RAR) within an RA response window during the triggered random access procedure.

[0055] With respect to the method of FIG. 5, the PDCCH command includes a field set to a value to explicitly indicate whether the device monitors or receives a random access response (RAR) within the RA response window during the triggered random access procedure.

[0056] With respect to the method of FIG. 5 , the first list of random access preamble resources is associated with monitoring or receiving a random access response (RAR) within a random access (RA) response window during the triggered random access procedure, the second list of random access preamble resources is associated with not monitoring or receiving a random access response (RAR) within the random access (RA) response window during the triggered random access procedure, and the message includes a random access preamble resource from the second list of random access preambles to implicitly indicate that the device will not monitor or receive a random access response (RAR) within the random access (RA) response window during the triggered random access procedure.

[0057] According to an example embodiment, a UE may receive a downlink (DL) message such as a PDCCH command, which (1) may request the UE to perform a random access (RA) procedure to a particular target candidate cell and identify an RA preamble resource that the UE should use to transmit the RA preamble, (2) the RA preamble may be associated with a target DL reference signal (e.g., SSB or CSI RS) of that cell, and (3) the PDCCH command may include information indicating whether the UE should monitor or receive an RAR for that RA procedure.

[0058] A UE may typically monitor a DL RS associated with an RA preamble resource, e.g., to estimate timing, so that the UE may transmit an RA preamble using the estimated UL timing. The UE transmits an RA preamble on a configured RA preamble resource, and the UE may select the best UE beam based on the DL RS. Thus, the UE may receive a DL reference signal associated with an RA preamble, e.g., to select a UE beam for transmitting the preamble and to obtain DL timing (symbol timing and timing reference for the UL transmission) used for uplink (UL) transmission of the RA preamble, which uses the same timing.

[0059] After the UE receives this PDCCH command, the UE identifies an RA preamble resource associated with the DL RS of the target cell (the target cell may also be the serving cell), and the UE selects a beam for the UE's UL RA preamble transmission and determines the timing (of the UL transmission of the RA preamble) based on the DL RS. The UE transmits the RA preamble. Also, according to example embodiments, the message (e.g., PDCCH command) received by the UE may indicate whether the UE will monitor or receive a random access response (RAR) within an RA response window during the triggered random access procedure.

[0060] In one embodiment, a field in a DCI message that triggers a PDCCH order may indicate whether the UE monitors and receives (or should monitor and receive, or is required to monitor and receive) an RAR for the triggered random access procedure. Also, for example, this field in the DCI message or PDCCH order may indicate whether the UE is assumed to receive (or will receive) an RAR response for the random access procedure initiated by the PDCCH order. The DCI message that schedules the PDCCH order may include a field (e.g., 1 bit or N bits or a codepoint value or values ​​for a table lookup) that indicates whether the UE is configured to monitor the RA response window for the RA response of the triggered random access preamble transmission. Based on the value of this field, the UE may then monitor and receive (or not monitor and receive) an RAR for the triggered RA procedure that the UE initiated based on the PDCCH order.

[0061] In some cases, the network device or network node may later send a TA (either the TA of the same cell to which the UE is connected or the TA of another cell, such as a candidate target cell) to the UE if the UE's UL timing needs to be updated for those cells.

[0062] Also, according to example embodiments, the UE may receive a timing advance (TA) for one or more candidate target cells outside of the random access procedure (e.g., a TA forwarded to the UE by a serving or source cell or network device, which may have been received by the network device or serving cell from the candidate target cell). In one embodiment, if the DCI (triggering the PDCCH command) indicates that the UE is not configured (or not assumed, or not activated, or not indicated) to monitor or receive an RA response for that random access procedure, the UE must assume that the random access procedure has been successfully completed after the UE transmitted an RA preamble (and therefore, the UE does not need to monitor or receive an RA response for that random access procedure). In this case, the network (e.g., a network device or network node, or a serving or source cell) may receive the UE's transmission (transmitted preamble) and determine whether the (new) TA value should be used and / or provided to at least one of the cells (which may be covered by one or more DL RSs that may be associated with one or more TRPs).

[0063] Alternatively, for example, a cell receiving an RA preamble configured for inter-cell beam management (or lower layer mobility) (e.g., a candidate target cell / serving cell / cells from which the UE transmitted an RA preamble) may provide (or transmit) information regarding the TA value detected or observed by the candidate target cell based on the UE's transmission of the RA preamble to the serving cell or a network device or network node. Thus, the UE may not monitor or receive an RAR containing a TA value, but the candidate target cell may transmit the UE's TA value (e.g., an estimate of the TA value) (based on the received RA preamble) to the serving cell, source cell, or network device (e.g., a gNB serving the UE). In one example, the serving cell may negotiate (e.g., request or indicate) with one or more candidate target cells to determine and / or indicate specific RA preamble resources or transmissions that do not require an RA response. For example, the RA transmission is performed using the target cell's RA resources, so the cells may negotiate which resources may be used for the RA transmission. The candidate target cell (from which the UE transmitted the RA preamble) may determine a TA value and then transmit this TA value for the UE to the UE's serving cell. As mentioned, the UE may transmit RA preambles to multiple candidate target cells, for example, based on different / multiple PDCCH instructions (or multiple instructions within the PDCCH instruction or one DCI), and the candidate target cell may determine a TA value for the UE and transmit the TA value to the serving cell. Thus, for example, the candidate target cell may receive the RA preamble, determine a TA value for the UE, and then report these TA values ​​for the UE to the serving cell, the source cell, or a network device (or network node).The serving or source cell, or a network device or network node controlling the serving cell, may then forward a group of these TAs to the UE, which can be a much more efficient technique for the UE to obtain TA values ​​for multiple candidate target cells compared to monitoring and receiving the RAR and TA from each of these candidate target cells.

[0064] In one embodiment, random access preamble resources may be configured not to be associated with monitoring for RA responses. If the DCI (triggering the PDCCH command) indicates random access resources configured not to be associated with random access responses, the UE must assume that the random access procedure is completed successfully after the UE transmits the RA preamble (thus, in such a case, the UE does not monitor or receive an RAR for the triggered random access procedure). Instead of a PDCCH command explicitly indicating to monitor and receive (or not monitor and receive) an RAR for the triggered random access procedure, the RA preamble resources indicated in the PDCCH command may implicitly indicate whether the UE monitors and receives an RAR for this random access procedure. For example, a first list of random access preamble resources may be associated with monitoring or receiving a random access response (RAR) within a random access (RA) response window during the triggered random access procedure, and a second list of random access preamble resources is associated with not monitoring or receiving a random access response (RAR) within the random access (RA) response window during the triggered random access procedure. Thus, for example, the message (e.g., PDCCH order or DCI) may indicate or identify a random access preamble resource (e.g., a random access preamble index or identifier) ​​from the second list of random access preambles to implicitly indicate to the UE that the UE will not monitor or receive a random access response (RAR) within the random access (RA) response window during the triggered random access procedure. Thus, there may be a set of RA preambles that require RAR monitoring and another set of RA preambles for which no RAR is monitored or received, and the UE may be informed by the type of RA preamble received in the PDCCH order (or based on a preamble provided from either the first or second list of RA preambles).Therefore, there may be different techniques that may be used by a network device or a serving cell to inform the UE whether the UE should monitor and receive the RAR for the random access procedure.

[0065] The DL RS may be indicated by an RA preamble resource indication in the PDCCH order. If the UE is configured not to monitor the RAR, it may store or maintain a list of DL RSs indicated by the preamble indicated in the PDCCH order (DL RSs associated with the indicated RA preamble). Both the UE and the network device may store or maintain this list of DL RSs associated with a particular RA preamble, and the network device may associate one or more DL RSs with a TA value.

[0066] As an example, PDCCH command 1 may indicate not to monitor RA for cell 1 and indicate RA preamble index 1 associated with DL RS1. The network device or serving cell may later inform the UE that this is TA1 for this DL RS1 (MAC CE on the PDCCH). The UE may add DL RS1 and the associated TA1 to a list, or the UE may associate DL RS1 with TA1 used for communication for cell 1. Also, for example, the UE may receive PDCCH command 2 indicating not to monitor cell 2, and the PDCCH command indicates an RA preamble index (associated with a particular resource). For example, this PDCCH command 2 may indicate RA preamble index 2 and may indicate the RA preamble resource associated with DL RS2 and cell 2. A PCI / cell ID may be included in each PDCCH command. The UE now has the TAs for these cells in case the UE performs a cell change to one of these cells. The UE performs a cell change to a candidate target cell. The UE may have previously acquired or received the TA of such a candidate target cell, and therefore the UE does not need to perform an RA procedure as part of the cell change to acquire the TA of such a candidate target cell. After the cell change is initiated, the UE can change beams and the UE has a TA for UL transmission without waiting for a random access procedure to be performed.

[0067] In example embodiments, the UE may track for which cells the network (e.g., a network device, network node, or serving or source cell) has triggered a PDCCH order for the UE (e.g., the UE may maintain or store a list of cells), and the UE may then later receive the TA values ​​for those cells, e.g., from the network device or network node, serving or source cell. For example, for a DL RS (or PCI or DL-RS+PCI) indicated in the PDCCH order (indicated via an indicated preamble index, e.g., the RA preamble index is associated with the DL RS) for which an RA response was not configured to be monitored, the resource index / indicator of the resource of the DL RS (or PCI or DL-RS+PCI) is stored by the UE in a list of (timing advance reference) DL resources (or PCI or DL-RS+PCI). The network can reference one or more DL RS resources (or PCI or DL-RS+PCI) in the list and provide the DL RS (or PCI or DL-RS+PCI) with an associated TA value to the UE (based on the UE's random access preamble transmission). This allows the UE to communicate with the (target) cell using the TA value via the association provided (by the list). To enable complete mutual understanding of the lists, the network may maintain a similar list on the network side (lists of DL RSs (or PCI or DL-RS+PCI) and preamble resource indexes). The maximum list size may be predefined or configured by the network. Any DL RS in the list may be associated with a PCI value (e.g., an SSB reference signal-PCI (cell identity) association pair). In this way, the UE and network device may maintain an association between the DL RS and the TA (or cell identity / PCI and the TA). This information may be used for inter-cell beam management. This information may be used in any further communication with the cell associated with the TA (or for cell change or cell switching / handover).If the DCI message or PDCCH command indicates that the UE is not required to monitor RA responses (i.e., no TA is provided in response to the RA preamble transmission), the network may provide a TA value associated with one of the DL RSs / cells in the list (e.g., associated with a new TAG / TA loop), where the list entries are based on the DL RSs indicated in the PDCCH command (e.g., associated with a PCI different from that of the target cell). Each entry in the list may have a validity timer. The maximum value of the validity timer may be predefined or configured by the network. The validity timer may be started after successful completion of the RA procedure (and / or when the entry is added). The entry is removed upon timer termination / expiration (i.e., when the validity timer value is equal to or greater than the maximum value, or alternatively, when it counts down to zero). If a timer associated with an entry in the list is running, the NW may refer to the entry and provide the associated TA value. When the UE receives a new TA value associated with a DL RS included in the list (and further a PCI associated with the DL RS, such as an SSB), it assumes any UL transmission according to the TA associated with the TA loop / TAG ID.

[0068] If the network device or serving cell indicates that the UE monitors the RAR for a cell or random access procedure, the UE receives the TA via the RAR, but the serving cell that triggered the PDCCH command does not know whether and when the triggered RA procedure was successful. Therefore, in an example embodiment, the UE may notify (or send a message to) the serving cell or network device of the successful completion of the RA procedure with this candidate target cell. In another example embodiment, the UE may be configured to notify (or send a message to) the serving cell or network device of the successful completion of the RA procedure (RA or contention-based random access (CBRA) procedure via a PDCCH command) with the (candidate target) cell. In some examples, a PDCCH command may be used to trigger the CBRA procedure. In some examples, the UE may be configured to report the obtained TA of a cell (e.g., the TA of a candidate target cell) to the serving cell.

[0069] In one embodiment, if the DCI triggers a PDCCH command and the target preamble index (and associated DL RS, e.g., SSB / CSI-RS) of the PRACH transmission is associated with a cell with a different PCI than the serving cell, the UE is configured to notify the serving cell of the successful completion of the RA procedure. The serving cell or network device may include a request to the UE for a report of the successful completion of such an RA procedure via a new field in the DCI that triggers the RA procedure via the PDCCH command. Alternatively, the network (or network device or network node) may configure the UE to report the cells from which the UE has obtained a TA (e.g., via the RA procedure). This report may also include the TA value. As an example, the UE may be configured to report the cells from which the UE has obtained a TA value (in other words, the cells with which the UE is uplink time aligned (e.g., the cells with which the UE has a TA value)), e.g., using RRC (or RRC+MAC CE or MAC CE). This report may be provided to the network (e.g., to a network device or network node, a serving cell, or a source cell) upon completion of the RA procedure (when the TA is received) or when the UE can be considered to have acquired or been uplink time aligned to a specific cell or cells. The cell or specific cell may also include the serving cell (e.g., if one or more TA values ​​are supported for one (serving) cell). The request (or configuration) may also indicate, for example, whether the UE should report successful acquisition of the target cell's TA / timing. If the PDCCH command indicates that the UE monitors the RAR response of the triggered RA preamble transmission, the UE may determine that the UE must report the successful completion of the random access procedure to the serving cell. The UE may indicate, within one message (MAC-CE), the PCI(s) (and / or DL ​​RS(s)) on which the PDCCH command is completed and on which the UE received the TA value. In one further example, the PCI is a cell configured as an LLM candidate cell (lower layer mobility).If the UE indicates a PCI that it has a valid TA for the cell, the UE assumes that the beam application time is based on known TCI state conditions. In one example, the PDCCH command may trigger a CBRA (contention-based random access) procedure (i.e., no RA preamble is specifically reserved). The UE may be configured, via the triggering DCI, to report the obtained TA value and / or report an indication of which cell (e.g., LLM cell) the UE is currently time-aligned to (has the TA value of). The list of cells to which the UE has a TA value (the UE's time-aligned cell list) may be monitored or managed through the use of timers, including removing or discarding TA values / cells from the list when the respective timers expire (indicating that such TA value is out of date or no longer accurate). In some examples, the network (e.g., a network node or network device, cell, or candidate target cell) that received the RA transmission by the UE and determined the TA value associated with the RA transmission / procedure may transmit / indicate the TA value to the serving cell. This indication may be provided upon completion of the RA procedure. By way of example, a network node may be configured to signal a TA value associated with the UE (or an indication that the UE is UL time aligned with a cell) to another network node (the TA value may have been obtained using the RA procedure or may have been determined based on UL transmissions with that cell).

[0070] In one embodiment, the network or serving cell / network device may configure the UE to update the TA of at least one cell (or transmission reception point (TRP) determined based on the set of DL RSs) associated with the PCI of the serving cell or a PCI other than the serving cell, and may trigger a PDCCH command to the UE indicating that monitoring of RAR responses is not required. This transmission updates the TA observed by one or more target cells, and the network may then provide the UE with the TA value when it has determined the cell to which the UE will be handed over (or a cell to which the UE can or is likely to perform a cell change). This may be beneficial for the UE as it does not need to maintain multiple TAs before handover.

[0071] In one embodiment, the network may configure the UE to acquire a TA for at least one cell having a PCI different from the serving cell, and upon acquiring the TA, report successful acquisition to the source cell. In one embodiment, any of the above embodiments may be conditioned on the case where the UE of the serving cell is configured with multiple TA values ​​(e.g., multiple TAGs), and / or in one embodiment, the RRC configuration may be provided regardless of whether the bit field is present in the DCI.

[0072] Some further examples are provided.

[0073] Example 1 An apparatus comprising at least one processor and at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus to at least perform the following: obtain a message instructing the apparatus to trigger or initiate a random access (RA) procedure to access a cell of a network device, the message indicating whether the apparatus will monitor for or receive a random access response (RAR) within an RAR window during the triggered random access procedure; and determine, based on the instruction, whether to monitor for or receive an RAR within the RAR window.

[0074] Example 2 2. The apparatus of embodiment 1, wherein the message includes downlink control information (DCI) received over a physical downlink control channel (PDCCH).

[0075] Example 3 3. The apparatus of any one of the preceding embodiments, wherein the message includes a field that triggers or causes a physical downlink control channel (PDCCH) command to indicate whether the apparatus monitors or receives an RAR response within an RAR window during a triggered random access procedure initiated via the PDCCH command.

[0076] Example 4 4. The apparatus of example 3, wherein the field includes at least one of 1 bit, N bits, a code point value, or a value used as a table lookup, where N is a positive integer.

[0077] Example 5 The device of any of Examples 1 to 4, wherein the instructions, when executed by at least one processor, cause the device to at least determine or assume that the triggered random access procedure has completed successfully after an RA preamble transmission from the device to a cell of the network device for the triggered random access procedure if the message indicates that the device does not monitor or receive an RAR within the RAR window during the triggered random access procedure.

[0078] Example 6 The apparatus of any of Examples 1 to 5, wherein the instructions, when executed by at least one processor, cause the apparatus to at least determine or assume that a triggered random access procedure has completed successfully after a random access (RA) preamble transmission from the apparatus to a cell of a network device corresponding to a random access preamble resource for the triggered random access procedure, if the instructions indicate that the random access preamble resource is configured not to be associated with an RAR.

[0079] Example 7 The apparatus of any of Examples 3 to 6, wherein the instructions, when executed by at least one processor, cause the apparatus to at least: acquire a downlink reference signal (DL RS) indicated in the PDCCH instruction; and determine, based on the DL RS, whether an RAR is configured to be monitored or received by the apparatus within an RAR window during a triggered random access procedure.

[0080] Example 8 The apparatus of any one of embodiments 3-7, wherein the instructions, when executed by the at least one processor, cause the apparatus to at least store resources associated with the DL RS in a list of downlink resources.

[0081] Example 9 9. The apparatus of any of embodiments 3-8, wherein the list of downlink resources includes one or more timing advance (TA) references or values.

[0082] Example 10 10. The apparatus of any of embodiments 3-9, wherein a size of the list of downlink resources is predefined or configured by the network device.

[0083] Example 11 11. The apparatus of any of embodiments 8-10, wherein each downlink resource list is associated with a corresponding physical cell identity (PCI) value.

[0084] Example 12 12. The apparatus of any of embodiments 8-11, wherein each list of downlink resources is associated with a corresponding validity timer.

[0085] Example 13 13. The apparatus of embodiment 12, wherein a maximum value for each of the validity timers is predefined or configured by the network device.

[0086] Example 14 14. The apparatus of any of embodiments 8-13, wherein each validity timer is started after successful completion of the triggered random access procedure.

[0087] Example 15 The apparatus of any of Examples 8 to 14, wherein the instructions, when executed by at least one processor, cause the apparatus to at least perform: obtaining a timing advance (TA) value associated with at least one downlink resource in a list of downlink resources for the triggered random access procedure, if the instructions indicate that the apparatus does not monitor or receive an RAR within the RAR window during the triggered random access procedure.

[0088] Example 16 16. The apparatus of example 15, wherein the obtained timing advance (TA) value is different from a TA value currently in use in the cell of the network device for the triggered random access procedure.

[0089] Example 17 The apparatus of example 15 or example 16, wherein the instructions, when executed by at least one processor, cause the apparatus to at least perform, when obtaining a timing advance (TA) value, performing one or more subsequent uplink transmissions to a cell of the network device according to the obtained TA value.

[0090] Example 18 18. The apparatus of any of Examples 3-17, wherein the instructions, when executed by at least one processor, cause the apparatus to at least: indicate successful completion of the triggered random access procedure to a cell of the network device if the instructions indicate that downlink control information (DCI) triggers or causes a PDCCH command and that a target downlink reference signal (DL RS) of a random access (RA) preamble transmission is associated with a cell different from the cell of the network device.

[0091] Example 19 The apparatus of any of Examples 3 to 18, wherein the instructions, when executed by at least one processor, cause the apparatus to at least perform: determining whether to report successful completion of a triggered random access procedure to a cell of the network device if the PDCCH instructions indicate that the apparatus monitors or receives a random access (RA) preamble transmission RAR.

[0092] Example 20 The apparatus of example 19, wherein the instructions, when executed by at least one processor, cause the apparatus to at least perform the following: indicate, to a cell of the network device, one or more physical cell identities (PCIs) where at least one of the RA procedures triggered by the PDCCH command is completed or a timing advance (TA) value is received.

[0093] Example 21 20. The apparatus of example 19, wherein one or more physical cell identities (PCIs) are indicated via a medium access control control element (MAC-CE).

[0094] Example 22 22. The device of any of Examples 1 to 21, wherein the message includes a random access preamble resource and a physical downlink control channel (PDCCH) command instructing the device to perform a triggered random access procedure, and the PDCCH command explicitly or implicitly indicates whether the device monitors or receives a random access response (RAR) within an RA response window during the triggered random access procedure.

[0095] Example 23 23. The apparatus of example 22, wherein the PDCCH command includes a field set to a value to explicitly indicate whether the apparatus monitors or receives a random access response (RAR) within an RA response window during the triggered random access procedure.

[0096] Example 24 23. The apparatus of example 22, wherein a first list of random access preamble resources is associated with monitoring or receiving a random access response (RAR) within a random access (RA) response window during the triggered random access procedure, and a second list of random access preamble resources is associated with not monitoring or receiving a random access response (RAR) within the random access (RA) response window during the triggered random access procedure, and the message includes a random access preamble resource from the second list of random access preambles to implicitly indicate that the apparatus will not monitor or receive a random access response (RAR) within the random access (RA) response window during the triggered random access procedure.

[0097] Example 25 A method comprising: obtaining, by a user device, a message instructing the user device to trigger or initiate a random access (RA) procedure to access a cell of a network device, the message indicating whether the device will monitor for or receive a random access response (RAR) within an RAR window during the triggered random access procedure; and determining, by the user device, based on the instruction, whether to monitor for or receive an RAR within the RAR window.

[0098] Example 26 26. The method of example 25, wherein the message includes downlink control information (DCI) received over a physical downlink control channel (PDCCH).

[0099] Example 27 27. The method of example 25 or 26, wherein the message includes a field that triggers or causes a physical downlink control channel (PDCCH) command that indicates whether the device monitors or receives an RAR response within an RAR window during a triggered random access procedure initiated via the PDCCH command.

[0100] Example 28 28. The method of example 27, wherein the field includes at least one of 1 bit, N bits, a code point value, or a value used as a table lookup, where N is a positive integer.

[0101] Example 29 29. The method of any of Examples 25 to 28, comprising determining or assuming by the device that the triggered random access procedure has completed successfully after transmitting an RA preamble from the device to the cell of the network device for the triggered random access procedure if the message indicates that the device does not monitor or receive an RAR within the RAR window during the triggered random access procedure.

[0102] Example 30 30. The method of any of Examples 25 to 29, comprising determining or assuming that the triggered random access procedure has been successfully completed after a random access (RA) preamble transmission from the apparatus to a cell of the network device corresponding to the random access preamble resource for the triggered random access procedure, if the instruction indicates that the random access preamble resource is configured not to be associated with an RAR.

[0103] Example 31 31. The method of any of Examples 25 to 30, comprising: obtaining a downlink reference signal (DL RS) indicated in the PDCCH command; and determining, based on the DL RS, whether an RAR is configured to be monitored or received by the device within an RAR window during the triggered random access procedure.

[0104] Example 32 32. The method of any of embodiments 27-31, comprising storing resources associated with the DL RS in a list of downlink resources.

[0105] Example 33 33. The method of any of embodiments 27-32, wherein the list of downlink resources includes one or more timing advance (TA) references or values.

[0106] Example 34 34. The method of any of embodiments 27-33, wherein the size of the list of downlink resources is predefined or configured by the network device.

[0107] Example 35 35. The method of any of embodiments 32-34, wherein each downlink resource list is associated with a corresponding physical cell identity (PCI) value.

[0108] Example 36 36. The method of any of embodiments 32-35, wherein each downlink resource list is associated with a corresponding validity timer.

[0109] Example 37 37. The apparatus of embodiment 36, wherein a maximum value for each of the validity timers is predefined or configured by the network device.

[0110] Example 38 38. The method of any of embodiments 32-37, wherein each validity timer is started after successful completion of the triggered random access procedure.

[0111] Example 39 39. The method of any of examples 32 to 38, comprising, when the instruction indicates that the device will not monitor or receive an RAR within the RAR window during the triggered random access procedure, obtaining a timing advance (TA) value associated with at least one downlink resource in the list of downlink resources for the triggered random access procedure.

[0112] Example 40 39. The method of embodiment 39, wherein the obtained timing advance (TA) value is different from the TA value currently in use in the cell of the network device for the triggered random access procedure.

[0113] Example 41 41. The method of embodiment 39 or 40, comprising, upon obtaining a timing advance (TA) value, performing one or more subsequent uplink transmissions to the cell of the network device according to the obtained TA value.

[0114] Example 42 42. The method of any of embodiments 27-41, comprising indicating successful completion of the triggered random access procedure to the cell of the network device if the indication indicates that downlink control information (DCI) triggers or causes a PDCCH command and that a target downlink reference signal (DL RS) of the random access (RA) preamble transmission is associated with a cell different from the cell of the network device.

[0115] Example 43 43. The method of any of embodiments 27 to 42, comprising determining whether to report successful completion of the triggered random access procedure to a cell of the network device if the PDCCH command indicates that the device monitors or receives a random access (RA) preamble transmission RAR.

[0116] Example 44 44. The method of embodiment 43, comprising indicating one or more physical cell identities (PCIs) to a cell of the network device where at least one of the RA procedures triggered by the PDCCH command is completed or a timing advance (TA) value is received.

[0117] Example 45 45. The method of example 44, wherein one or more physical cell identities (PCIs) are indicated via a medium access control control element (MAC-CE).

[0118] Example 46 46. ​​The method of any of embodiments 25 to 45, wherein the message includes a random access preamble resource and a physical downlink control channel (PDCCH) command instructing the device to perform a triggered random access procedure, and the PDCCH command explicitly or implicitly indicates whether the device monitors or receives a random access response (RAR) within an RA response window during the triggered random access procedure.

[0119] Example 47 47. The method of example 46, wherein the PDCCH command includes a field set to a value to explicitly indicate whether the device monitors or receives a random access response (RAR) within an RA response window during the triggered random access procedure.

[0120] Example 48 47. The device of example 46, wherein a first list of random access preamble resources is associated with monitoring or receiving a random access response (RAR) within a random access (RA) response window during the triggered random access procedure, and a second list of random access preamble resources is associated with not monitoring or receiving a random access response (RAR) within the random access (RA) response window during the triggered random access procedure, and the message includes a random access preamble resource from the second list of random access preambles to implicitly indicate that the device will not monitor or receive a random access response (RAR) within the random access (RA) response window during the triggered random access procedure.

[0121] Example 49 An apparatus comprising: means for obtaining, by a user device, a message instructing the user device to trigger or initiate a random access (RA) procedure to access a cell of a network device, the message indicating whether the device will monitor for or receive a random access response (RAR) within an RAR window during the triggered random access procedure; and means for determining, by the user device, based on the instruction, whether to monitor for or receive an RAR within the RAR window.

[0122] Example 50 A non-transitory computer-readable storage medium containing stored instructions that, when executed by at least one processor, are configured to cause a computing system to: obtain a message instructing an apparatus to trigger or initiate a random access (RA) procedure to access a cell of a network device, the message indicating whether the apparatus will monitor or receive a random access response (RAR) within an RAR window during the triggered random access procedure; and, based on the instruction, determine whether to monitor or receive an RAR within the RAR window.

[0123] 6 is a block diagram of a wireless station or node (e.g., UE, user device, AP, BS, eNB, gNB, RAN node, network node, TRP, or other node) 1200 according to an example embodiment. The wireless station 1200 may include, for example, one or more (e.g., two as shown in FIG. 6) radio frequency (RF) or wireless transceivers 1202A, 1202B, each including a transmitter for transmitting signals and a receiver for receiving signals. The wireless station also includes a processor or control unit / entity (controller) 1204 for executing instructions or software and controlling the transmission and reception of signals, and a memory 1206 for storing data and / or instructions.

[0124] The processor 1204 may make judgments or decisions, generate frames, packets, or messages for transmission, decode received frames or messages for further processing, and perform other tasks or functions described herein. The processor 1204, which may be a baseband processor, may generate, for example, messages, packets, frames, or other signals for transmission via the wireless transceiver 1202 (1202A or 1202B). The processor 1204 may control the transmission of signals or messages over the wireless network and may control the reception of signals, messages, etc. (e.g., after being downconverted by the wireless transceiver 1202) over the wireless network. The processor 1204 may be programmable and may be capable of executing software or other instructions stored in memory or other computer media to perform various tasks and functions described above, such as one or more of the tasks or methods described above. The processor 1204 may be (or include), for example, hardware, programmable logic, a programmable processor executing software or firmware, and / or any combination thereof. Using other terminology, the processor 1204 and the transceiver 1202 may together be considered, for example, a wireless transmitter / receiver system.

[0125] Additionally, with reference to FIG. 6, controller (or processor) 1208 may execute software and instructions and may provide overall control of wireless station 1200, may provide control of other systems not shown in FIG. 6, such as controlling input / output devices (e.g., display, keypad), and / or may execute software for one or more applications that may be provided on wireless station 1200, such as, for example, an email program, an audio / video application, a word processor, a voice-over-IP application, or other application or software.

[0126] Additionally, a storage medium containing stored instructions may be provided that, when executed by a controller or processor, may cause the processor 1204 or other controller or processor to perform one or more of the functions or tasks described above.

[0127] According to another example embodiment, the RF or wireless transceiver 1202A / 1202B may receive signals or data and / or transmit signals or data. The processor 1204 (and, in some cases, the transceiver 1202A / 1202B) may control the RF or wireless transceiver 1202A or 1202B to receive, transmit, or broadcast signals or data.

[0128] Embodiments of the various techniques described herein may be implemented in digital electronic circuitry, or in computer hardware, firmware, software, or combinations of them. Embodiments may be implemented as a computer program product, i.e., as a computer program tangibly embodied in an information medium (e.g., a machine-readable storage device) or in a propagated signal, for execution by or to control the operation of a data processing apparatus (e.g., a programmable processor, a computer, or multiple computers). Embodiments may be provided on a computer-readable medium or computer-readable storage medium, which may be a non-transitory medium. Embodiments of the various techniques may include embodiments provided via a transitory signal or medium and / or embodiments of programs and / or software downloadable via the Internet or other networks (either wired and / or wireless). Additionally, embodiments may be provided via machine-type communications (MTC) or the Internet of Things (IoT).

[0129] The computer program may be in the form of source code, object code, or some intermediate form and may be stored on some kind of carrier, distribution medium, or computer-readable medium, which may be any entity or device capable of carrying a program. Such carriers include, for example, recording media, computer memory, read-only memory, optical-electronic and / or electrical carrier signals, telecommunications signals, and software distribution packages. Depending on the processing power required, the computer program may be executed in a single electronic digital computer or distributed among several computers.

[0130] Furthermore, embodiments of the various technologies described herein may use cyber-physical systems (CPSs) (systems of computing elements working together to control physical entities). CPSs may enable the implementation and utilization of vast amounts of interconnected ICT devices (sensors, actuators, processors, microcontrollers, etc.) embedded in objects at various locations. Mobile cyber-physical systems, in which the physical systems in question have inherent mobility, are a subcategory of cyber-physical systems. Examples of mobile physical systems include mobile robotics and electronic devices carried by humans or animals. The increasing popularity of smartphones has sparked interest in the area of ​​mobile cyber-physical systems. Accordingly, various embodiments of the technologies described herein may be provided via one or more of these technologies.

[0131] A computer program such as the one described above can be written in any form of programming language, including compiled or interpreted languages, and can be deployed in any form suitable for use in a computing environment, including as a stand-alone program or as a module, component, subroutine, or other unit or portion thereof. A computer program can be deployed to be executed on one computer or on multiple computers, either at one site or distributed across multiple sites and interconnected by a communications network.

[0132] The method steps may be performed by one or more programmable processors running computer programs or portions of computer programs to perform functions by operating on input data and generating output. The method steps may also be performed by, and an apparatus may be implemented as, special purpose logic circuitry, such as an FPGA (field programmable gate array) or an ASIC (application-specific integrated circuit).

[0133] Examples of processors suitable for executing a computer program include both general-purpose and special-purpose microprocessors, and any one or more processors of any kind of digital computer, chip, or chipset. Typically, a processor receives instructions and data from a read-only memory and / or a random-access memory. Elements of a computer may include at least one processor for executing instructions and one or more memory devices for storing instructions and data. Typically, a computer will include one or more mass storage devices (e.g., magnetic, magneto-optical, or optical disks) for storing data, and / or be operatively coupled to receive or transfer data from such mass storage devices. Information media suitable for embodying computer program instructions and data include all forms of non-volatile memory, such as, for example, semiconductor memory devices (e.g., EPROM, EEPROM, and flash memory devices), magnetic disks (e.g., internal hard disks or removable disks), magneto-optical disks, and CD-ROM and DVD-ROM disks. The processor and memory may be supplemented by, or incorporated in, special-purpose logic circuitry.

[0134] To provide for user interaction, embodiments may be implemented on a computer that includes a user interface, such as a display device, e.g., a cathode ray tube (CRT) or liquid crystal display (LCD) monitor, for displaying information to the user, and a keyboard and pointing device (e.g., a mouse or trackball) that the user can use to provide input to the computer. Other types of devices may also be used to provide for user interaction. For example, feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback), and input from the user may be received in any form, including acoustic, speech, or tactile input.

[0135] Embodiments may be implemented in a computing system that includes back-end components, e.g., as a data server, or middleware components, e.g., as an application server, or front-end components (e.g., a client computer that includes a graphical user interface or web browser through which a user can interact with the embodiments), or any combination of such back-end, middleware, or front-end components. The components may be interconnected by any form or medium of digital data communication (e.g., a communication network). Examples of communication networks include a local-area network (LAN) and a wide-area network (WAN) (e.g., the Internet).

[0136] As set forth herein, while certain features of the described embodiments have been illustrated, many modifications, substitutions, changes, and equivalents will now occur to those skilled in the art. It is therefore to be understood that the appended claims are intended to cover all such modifications and changes as fall within the true spirit of the various embodiments.

Claims

1. at least one processor; at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus to: obtaining a message instructing the device to trigger or initiate a random access (RA) procedure to access a cell of a network device, the message indicating whether the device will monitor or receive a random access response (RAR) within an RAR window during the triggered random access procedure; and determining whether to monitor or receive the RAR within the RAR window based on the instruction.

2. 10. The apparatus of claim 1, wherein the message includes downlink control information (DCI) received over a physical downlink control channel (PDCCH).

3. 3. The device of claim 1 or 2, wherein the message includes a field that triggers or causes a physical downlink control channel (PDCCH) command indicating whether the device monitors or receives the RAR response within the RAR window during the triggered random access procedure initiated via the PDCCH command.

4. 4. The apparatus of claim 3, wherein the field includes at least one of 1 bit, N bits, a code point value, or a value used as a table lookup, where N is a positive integer.

5. The instructions, when executed by the at least one processor, cause the device to: An apparatus as described in any one of claims 1 to 4, which at least performs the following: if the message indicates that the apparatus does not monitor or receive the RAR within the RAR window during the triggered random access procedure, after transmitting an RA preamble from the apparatus to the cell of the network device for the triggered random access procedure, the apparatus determines or assumes that the triggered random access procedure has been completed successfully.

6. The instructions, when executed by the at least one processor, cause the device to: The device of any one of claims 1 to 5, wherein if the instruction indicates that a random access preamble resource is configured not to be associated with the RAR, the device at least determines or assumes that the triggered random access procedure has been completed successfully after transmitting a random access (RA) preamble from the device to the cell of the network device corresponding to the random access preamble resource for the triggered random access procedure.

7. The instructions, when executed by the at least one processor, cause the device to: Obtaining a downlink reference signal (DL RS) indicated in the PDCCH order; The device according to any one of claims 3 to 6, further comprising: determining, based on the DL RS, whether the RAR is configured to be monitored or received by the device within the RAR window during the triggered random access procedure.

8. The instructions, when executed by the at least one processor, cause the device to: The device according to any one of claims 3 to 7, configured to at least store resources associated with said DL RS in a list of downlink resources.

9. The apparatus according to any one of claims 3 to 8, wherein the list of downlink resources comprises one or more Timing Advance (TA) criteria or values.

10. The apparatus according to any one of claims 3 to 9, wherein the size of the list of downlink resources is predefined or configured by the network device.

11. The apparatus of any of claims 8 to 10, wherein each said list of downlink resources is associated with a corresponding Physical Cell Identity (PCI) value.

12. The apparatus according to any one of claims 8 to 11, wherein each said list of downlink resources is associated with a corresponding validity timer.

13. The apparatus of claim 12 , wherein a maximum value for each of the validity timers is predefined or configured by the network device.

14. The apparatus according to any one of claims 8 to 13, wherein the respective validity timer is started after successful completion of the triggered random access procedure.

15. The instructions, when executed by the at least one processor, cause the device to: An apparatus as described in any one of claims 8 to 14, which is configured to at least perform the following: obtain a timing advance (TA) value associated with at least one downlink resource in the list of downlink resources for the triggered random access procedure when the instruction indicates that the apparatus will not monitor or receive the RAR within the RAR window during the triggered random access procedure.

16. 16. The apparatus of claim 15, wherein the obtained timing advance (TA) value is different from a TA value currently in use in the cell of the network device for the triggered random access procedure.

17. The instructions, when executed by the at least one processor, cause the device to:

17. The apparatus of claim 15 or 16, wherein the apparatus is configured to at least perform, upon obtaining a Timing Advance (TA) value, performing one or more subsequent uplink transmissions to the cell of the network device according to the obtained TA value.

18. The instructions, when executed by the at least one processor, cause the device to:

18. The apparatus of claim 3, wherein the indication is configured to at least: indicate successful completion of the triggered random access procedure to a cell of the network device if the downlink control information (DCI) triggers or causes the PDCCH order and if a target downlink reference signal (DL RS) of the random access (RA) preamble transmission indicates that the target DL RS is associated with a cell different from a cell of the network device.

19. The instructions, when executed by the at least one processor, cause the device to: The apparatus according to any one of claims 3 to 18, further comprising: an apparatus configured to at least determine whether to report successful completion of the triggered random access procedure to the cell of the network device when the PDCCH command indicates that the apparatus monitors or receives the random access (RA) preamble transmission.

20. The instructions, when executed by the at least one processor, cause the device to:

20. The apparatus of claim 19, further comprising: causing at least one of the RA procedures triggered by a PDCCH order to be completed or a Timing Advance (TA) value to be received, to indicate to the cell of the network device one or more Physical Cell Identities (PCIs).

21. 20. The apparatus of claim 19, wherein the one or more physical cell identities (PCIs) are indicated via a medium access control control element (MAC-CE).

22. The message is Random access preamble resources, and a physical downlink control channel (PDCCH) command instructing the device to perform the triggered random access procedure; The device of any of claims 1 to 21, wherein the PDCCH order explicitly or implicitly indicates whether the device monitors or receives a Random Access Response (RAR) within an RA response window during the triggered random access procedure.

23. 23. The apparatus of claim 22, wherein the PDCCH order includes a field set to a value to explicitly indicate whether the apparatus monitors for or receives a random access response (RAR) within an RA response window during the triggered random access procedure.

24. a first list of random access preamble resources associated with monitoring or receiving a random access response (RAR) within a random access (RA) response window during the triggered random access procedure; a second list of random access preamble resources associated with not monitoring or receiving a random access response (RAR) within a random access (RA) response window during the triggered random access procedure; 23. The apparatus of claim 22, wherein the message includes a random access preamble resource from the second list of random access preambles to implicitly indicate that the apparatus will not monitor or receive a random access response (RAR) within a random access (RA) response window during the triggered random access procedure.

25. obtaining, by a user device, a message instructing the user device to trigger or initiate a random access (RA) procedure to access a cell of a network device, the message indicating whether the device will monitor or receive a random access response (RAR) within an RAR window during the triggered random access procedure; and determining, by the user device, based on the instruction, whether to monitor or receive the RAR within the RAR window.

26. 26. The method of claim 25, wherein the message includes downlink control information (DCI) received over a physical downlink control channel (PDCCH).

27. 27. The method of claim 25 or 26, wherein the message includes a field that triggers or causes a Physical Downlink Control Channel (PDCCH) command that indicates whether the device monitors or receives the RAR response within the RAR window during the triggered random access procedure initiated via the PDCCH command.

28. 28. The method of claim 27, wherein the field comprises at least one of 1 bit, N bits, a code point value, or a value used as a table lookup, where N is a positive integer.

29. A method according to any one of claims 25 to 28, comprising determining or assuming by the device that the triggered random access procedure has been completed successfully after transmitting an RA preamble from the device to the cell of the network device for the triggered random access procedure if the message indicates that the device does not monitor or receive the RAR within the RAR window during the triggered random access procedure.

30. 30. A method according to any one of claims 25 to 29, comprising determining or assuming that the triggered random access procedure has been completed successfully after a random access (RA) preamble transmission from the apparatus to the cell of the network device corresponding to the random access preamble resource for the triggered random access procedure, if the indication indicates that a random access preamble resource is configured not to be associated with the RAR.

31. Obtaining a downlink reference signal (DL RS) indicated in the PDCCH order; and determining, based on the DL RS, whether the RAR is configured to be monitored or received by the device within the RAR window during the triggered random access procedure.

32. The method according to any of claims 27 to 31, comprising storing resources associated with said DL RS in a list of downlink resources.

33. The method according to any of claims 27 to 32, wherein the list of downlink resources comprises one or more Timing Advance (TA) criteria or values.

34. The method according to any of claims 27 to 33, wherein the size of the list of downlink resources is predefined or configured by the network device.

35. A method according to any of claims 32 to 34, wherein each said list of downlink resources is associated with a corresponding Physical Cell Identity (PCI) value.

36. The method according to any of claims 32 to 35, wherein each said list of downlink resources is associated with a corresponding validity timer.

37. 37. The apparatus of claim 36, wherein a maximum value for each of the validity timers is predefined or configured by the network device.

38. A method according to any of claims 32 to 37, wherein the respective validity timer is started after successful completion of the triggered random access procedure.

39. A method according to any one of claims 32 to 38, comprising obtaining a timing advance (TA) value associated with at least one downlink resource in the list of downlink resources for the triggered random access procedure when the indication indicates that the device will not monitor or receive the RAR within the RAR window during the triggered random access procedure.

40. 40. The method of claim 39, wherein the obtained timing advance (TA) value is different from a TA value currently in use in the cell of the network device for the triggered random access procedure.

41. 41. The method of claim 39 or 40, comprising, upon obtaining a timing advance (TA) value, performing one or more subsequent uplink transmissions to the cell of the network device in accordance with the obtained TA value.

42. 42. The method of any of claims 27 to 41, wherein the indication includes indicating successful completion of the triggered random access procedure to a cell of the network device if the downlink control information (DCI) indicates that the PDCCH order is triggered or caused and that a target downlink reference signal (DL RS) of the random access (RA) preamble transmission is associated with a cell different from a cell of the network device.

43. 43. The method of any of claims 27 to 42, comprising determining whether to report successful completion of the triggered random access procedure to the cell of the network device if the PDCCH command indicates that the device monitors or receives the random access (RA) preamble transmission.

44. 44. The method of claim 43, comprising indicating one or more physical cell identities (PCIs) to the cell of the network device where at least one of the RA procedures triggered by a PDCCH order is completed or a timing advance (TA) value is received.

45. 45. The method of claim 44, wherein the one or more physical cell identities (PCIs) are indicated via a medium access control control element (MAC-CE).

46. The message is Random access preamble resources, and a physical downlink control channel (PDCCH) command instructing the device to perform the triggered random access procedure; A method according to any of claims 25 to 45, wherein the PDCCH order explicitly or implicitly indicates whether the device is to monitor or receive a Random Access Response (RAR) within an RA response window during the triggered random access procedure.

47. 47. The method of claim 46, wherein the PDCCH order includes a field set to a value to explicitly indicate whether the device monitors for or receives a random access response (RAR) within an RA response window during the triggered random access procedure.

48. a first list of random access preamble resources associated with monitoring or receiving a random access response (RAR) within a random access (RA) response window during the triggered random access procedure; a second list of random access preamble resources associated with not monitoring or receiving a random access response (RAR) within a random access (RA) response window during the triggered random access procedure; 47. The apparatus of claim 46, wherein the message includes a random access preamble resource from the second list of random access preambles to implicitly indicate that the device will not monitor or receive a random access response (RAR) within a random access (RA) response window during the triggered random access procedure.

49. means for obtaining, by a user device, a message instructing the user device to trigger or initiate a random access (RA) procedure to access a cell of a network device, the message indicating whether the device will monitor or receive a random access response (RAR) within an RAR window during the triggered random access procedure; and means for determining, by the user device, whether to monitor or receive the RAR within the RAR window based on the instruction.

50. A non-transitory computer-readable storage medium containing stored instructions that, when executed by at least one processor, cause a computing system to: obtaining a message instructing the device to trigger or initiate a random access (RA) procedure to access a cell of a network device, the message indicating whether the device will monitor or receive a random access response (RAR) within an RAR window during the triggered random access procedure; and determining whether to monitor or receive the RAR within the RAR window based on the instructions.

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