Systems, methods, and devices for secondary cell activation with UE-specific reference signals

Abstract

The present disclosure relates to systems, methods, and devices for secondary cell activation with UE-specific reference signals. The techniques described herein may better ensure efficient fine time tracking during a second cell (SCell) activation procedure by using a user equipment (UE)-specific tracking reference signal (TRS). A primary cell (PCell) may provide the UE with a TRS configuration including a UE-specific reference signal (RS) with periodicity or aperiodicity. In response to receiving an SCell activation command from the PCell, the UE may perform cell activation with fine time tracking according to the UE-specific RS. Since the delay time of the UE-specific RS may be less than the delay time of a system synchronization block (SSB) from the SCell, the use of the UE-specific RS may expedite the cell activation procedure.

Description

[0001] This application is a divisional application of Chinese Patent Application No. 202180089799.4, filed on January 14, 2021, entitled "System, Method and Apparatus for Activating Secondary Cells Using UE-Specific Reference Signals". Citation of relevant applications

[0002] This application is a national phase entry application of international patent application PCT / CN2021 / 071807 entitled “SYSTEMS, METHODS AND DEVICES, FORSECONDARY CELL ACTIVATION WITH UE-SPECIFIC REFERENCE SIGNAL”, filed on January 14, 2021, the contents of which are incorporated herein by reference in their entirety. Technical Field

[0003] This disclosure relates to wireless communication networks, including techniques for secondary cell activation within the wireless communication network. Other aspects and techniques are also described. Background Technology

[0004] As the number of mobile devices within wireless networks and the demand for mobile data traffic continue to increase, system requirements and architectures are being modified to better address current and anticipated needs. One aspect of such networks may include carrier aggregation (CA) and radio resource management (RRM). For example, a base station in a primary cell can enable user equipment (UE) to activate communication with a base station in a secondary cell, resulting in CA scenarios involving both the primary and secondary cells for the UE. Summary of the Invention

[0005] In one aspect of this disclosure, a baseband processor for a user equipment (UE) is provided. The baseband processor is configured to perform operations when executing instructions stored in a memory, the operations including: receiving a tracking reference signal (TRS) configuration to configure an aperiodic TRS; receiving a secondary cell activation command; and, in response to receiving the secondary cell activation command and the TRS configuration, initiating a secondary cell activation process based on a timing between the timing of the secondary cell activation command and a first fully available TRS opportunity. Attached Figure Description

[0006] This disclosure will be readily understood and implemented through detailed description and accompanying drawings. The same reference numerals may designate the same features and structural elements. The drawings and corresponding descriptions are provided as non-limiting examples of aspects, embodiments, etc., of this disclosure, and references to “a” or “an” aspect, embodiment, etc., may not necessarily refer to the same aspect, embodiment, etc., and may mean at least one, one, or more, etc.

[0007] Figure 1 This is a diagram of an exemplary network according to one or more specific implementations described herein.

[0008] Figure 2 This is a timeline diagram of an example of secondary cell activation using User Equipment (UE) Specific Reference Signals (RS).

[0009] Figure 3 This is a flowchart of an exemplary procedure for activating a secondary cell using a UE-specific RS.

[0010] Figure 4 This is a sequence diagram of an exemplary procedure for activating a secondary cell using a UE-specific RS.

[0011] Figure 5 This is a diagram illustrating examples of components of a device according to one or more specific embodiments described herein.

[0012] Figure 6 This is a diagram of an exemplary interface of a baseband circuit according to one or more specific embodiments described herein. Detailed Implementation

[0013] The following detailed description relates to the accompanying drawings. The same reference numerals in different drawings can identify the same or similar features, elements, operations, etc. Furthermore, this disclosure is not limited to the following description, as other specific embodiments and structural or logical changes can be made without departing from the scope of this disclosure.

[0014] Mobile communication networks may include one or more types and / or generations of wireless communication networks, such as 4G, 5G, or New Radio (NR) networks. Such networks may include user equipment (UEs) and base stations. One aspect of mobile communication networks includes radio resource management (RMM), which may include the configuration, assignment, allocation, and management of radio resources (e.g., channels, bandwidth, carriers, etc.) within the network. For example, carrier aggregation (CA) may include scenarios where multiple carriers are allocated to a UE. In some scenarios, CA may involve carriers aggregated from different base stations.

[0015] For example, for purposes such as RRM and CA for the UE, the UE may connect to the first carrier on the first base station operating as a primary cell (PCell). The primary cell may perform a Radio Resource Control (RRC) connection reconfiguration procedure, which includes sending UE connection configuration information and an activation command for the second carrier on the first base station or the third carrier on a second base station operating as a secondary cell (SCell). The UE can respond to the configuration information and commands by searching for and connecting to the SCell, resulting in a CA scenario involving the PCell, SCell, and UE.

[0016] To connect to an SCell, the UE can perform timing synchronization, which may include coarse timing synchronization and fine timing synchronization (also referred to herein as fine time tracking). Coarse timing synchronization generates an initial estimate of the starting index or symbol for communication with the SCell, and fine time tracking refines the initial estimate toward an ideal or more accurate starting point for communication with the SCell. Because timing synchronization can be performed before SCell activation is complete, the duration involved in SCell activation can depend at least in part on the time involved in fine time tracking. Furthermore, since timing synchronization can depend on the reference signal (RS) from the signal synchronization block (SSB) of the SCell, the SCell activation time (or activation delay) can depend on the periodicity of the SCell's SSB.

[0017] For example, the SCell activation delay may include the duration between the end of the first complete SSB burst indicated by the SSB-based RRM Measurement Timing Configuration (SMTC) after slot n + Hybrid Automatic Repeat Request Time (Time_HARQ) + 3ms, where n is the time when the UE receives a Media Access Control (MAC) command including the SCell activation command, Time_HARQ is the duration associated with the HARQ message corresponding to the MAC command, and the NR slot length is the specified slot length used to perform fine time tracking during TRS. In another example, the SCell activation delay may be further extended to the RS time (Trs) indicated by the SMTC and provided by the measurement object, or the default duration. In yet another example, the SCell activation delay may include the duration between the UE completing the processing of the last activation command for the Physical Downlink Control Channel (PDCCH) Transmission Configuration Indicator (TCI), Physical Downlink Shared Channel (PDSCH) TCI (where applicable), and the timing of the first complete available SSB corresponding to the TCI state. Therefore, the activation time of an SCell can be long because the RS used for synchronization may depend on the periodicity of the SCell's SSB (e.g., 160 milliseconds) and sometimes other durations. These durations, in turn, delay SCell activation and CA.

[0018] The techniques described herein can improve SCell activation efficiency by implementing a UE-specific RS for fine-grained time tracking instead of a cell-specific RS (e.g., via SSB). The UE-specific RS can be configured to have short periodicity (e.g., shorter than the SCell's SSB periodicity) or be aperiodic and occur well within the SCell's SSB periodicity. In some implementations, the UE-specific RS used for fine-grained time tracking during the SCell activation process can be a Tracking Reference Signal (TRS). The network (e.g., PCell) can configure the TRS via the transmission of RRC messages that include SCell additions (e.g., via an RRC connection configuration procedure, an RRC connection reconfiguration procedure, etc.).

[0019] Subsequently, the PCell can send a Media Access Control (MAC) element, including an SCell activation command, to the UE. In response, the UE can perform the SCell's cell search procedure and Automatic Gain Control (AGC) adjustments. Additionally, the UE can use TRS to rapidly perform fine-tuned timing tracking and / or AGC (e.g., just before receiving and processing the next SSB from the SCell) and continue rapidly completing the SCell activation process.

[0020] In some implementations, the TRS of the SCell can be periodic or aperiodic. When the TRS is periodic, the delay of fine-grained time tracking and / or ACG can be based on the periodicity of the TRS. When the TRS is aperiodic, the delay of fine-grained time tracking and / or ACG can depend on network scheduling (e.g., when the TRS transmission is triggered). In some implementations, an aperiodic TRS can be transmitted shortly after the PCell transmits the SCell activation command to the UE. In some implementations, an aperiodic TRS can be triggered by the network (e.g., the PCell) via downlink control information (DCI) and / or MAC commands, which can be conveyed after the SCell activation command is sent to the UE. When TCI is configured by the network, the TRS can be transmitted after the UE successfully decodes the TCI command from the PCell. When TCI is not configured, the TRS can be transmitted after the UE receives a MAC CE with the SCell activation command. For example, a TRS can be transmitted in time slot n + (Time_HARQ + 3ms) / (NR time slot length), where n is the time when the UE receives the MAC CE, Time_HARQ is the time associated with the HARQ message of the MAC CE, and the New Radio (NR) time slot length is the specified time slot length used to perform fine time tracking during the TRS.

[0021] In some specific implementations, Time_FineTiming may include the duration between the UE completing the processing of the last activation command for the PDCCH TCI and PDSCH TCI (where applicable) and one of the following: 1) the first fully available SSB corresponding to the TCI state when TRS is not configured, or the first fully available TRS timing with the same TCI state when TRS is configured. Alternatively, when TRS is configured, Time_FineTiming may be further divided into two cases: periodic and aperiodic. When periodic TRS is configured, Time_FineTiming may be the periodicity of TRS. When aperiodic TRS is configured, Time_FineTiming may be the duration between the UE completing the processing of the last activation command for the PDCCH TCI and PDSCH TCI (where applicable) and the timing of the first fully available TRS timing with the same TCI state when TRS is configured.

[0022] In some specific implementations, regarding the RRM condition for fine-grained time tracking during SCell activation, Time_FirstSSB can be the duration from the start of the end of the first complete SSB burst indicated by the SMTC after slot n + Time_HARQ + 3ms. When the SMTC is configured on the target SCell, or when TRS is configured, Time_FirstSSB can be the duration from n + Time_HARQ + 3ms to the end of the first complete available TRS timing (if configured, with the same TCI state). In either scenario, Time_FirstSSB_MAX can be the time from n + Time_HARQ + 3ms to the end of the first complete available TRS timing (if configured, with the same TCI state).

[0023] Alternatively, when TRS is configured, the RRM condition can be further divided into two cases: periodic and aperiodic. When a periodic TRS is configured, Time_FirstSSB can be equal to Time_TRS, and Time_FirstSSB_MAX can be equal to Time_PRS, where Time_PRS is the periodicity of the PRS. When an aperiodic TRS is configured, Time_FirstSSB and Time_FirstSSB_MAX are the duration between the time it takes for the UE to complete processing of the SCell activation command and the timing of the first fully available TRS (if configured, with the same TCI state).

[0024] Figure 1This refers to an exemplary network 100 according to one or more specific implementations described herein. The exemplary network 100 may include UEs 110-1, 110-2, etc. (collectively referred to as "UE 110", and individually referred to as "UE 110"), a radio access network (RAN) 120, a core network (CN) 130, an application server 140, an external network 150, and satellites 160-1, 160-2, etc. (collectively referred to as "Satellite 160" and individually referred to as "Satellite 160"). As shown, network 100 may include a non-terrestrial network (NTN) comprising one or more satellites 160 communicating with UE 110 and RAN 120 (e.g., a Global Navigation Satellite System (GNSS)).

[0025] The systems and devices of Exemplary Network 100 may operate according to one or more communication standards, such as 2G, 3G, 4G (e.g., Long Term Evolution (LTE)) and / or 5G (e.g., New Radio (NR)) communication standards of the 3rd Generation Partnership Project (3GPP). Alternatively, one or more of the systems and devices of Exemplary Network 100 may operate according to other communication standards and protocols discussed herein, including future versions or generations of 3GPP standards (e.g., 6G, 7G, etc.), IEEE standards bodies (e.g., Wireless Metropolitan Area Network (WMAN), Global Microwave Access Interoperability (WiMAX), etc.).

[0026] As shown in the figure, UE 110 may include a smartphone (e.g., a handheld touchscreen mobile computing device capable of connecting to one or more wireless communication networks). Alternatively, UE 110 may include other types of mobile or non-mobile computing devices capable of wireless communication, such as personal data assistants (PDAs), pagers, laptops, desktop computers, wireless handheld terminals, etc. In some implementations, UE 110 may include an Internet of Things (IoT) device (or IoT UE) that may include a network access layer designed to utilize low-power IoT applications with ephemeral UE connections. Alternatively, IoT UEs may utilize one or more types of technologies such as machine-to-machine (M2M) communication or machine-type communication (MTC) (e.g., to exchange data with an MTC server or other device via a Public Land Mobile Network (PLMN), Proximity Services (ProSe) or Device-to-Device (D2D) communication, sensor networks, IoT networks, and more. Depending on the scenario, the M2M or MTC exchange of data may be machine-initiated, and the IoT network may include IoT UEs interconnected with ephemeral connections (which may include uniquely identifiable embedded computing devices within an internet infrastructure). In some scenarios, IoT UEs can execute background applications (e.g., keeping track of activity messages, status updates, etc.) to facilitate connectivity in IoT networks.

[0027] UE 110 can communicate and establish connections (e.g., communicatively coupled) with RAN 120, which may involve one or more radio channels 114-1 and 114-2, each of which may include a physical communication interface / layer. In some implementations, the UE may be configured with dual connectivity (DC) as multiple radio access technology (multiple RAT) or multiple radio dual connectivity (MR-DC), where a UE capable of multiple receptions and transmissions (Rx / Tx) can use resources provided by different network nodes (e.g., 122-1 and 122-2), which may be connected via non-ideal backhaul connections (e.g., one network node provides NR access and another provides E-UTRA for LTE or NR access for 5G). In such scenarios, one network node may act as a primary node (MN) and the other as a secondary node (SN). MN and SN may be connected via a network interface, and at least MN may be connected to CN 130. Additionally, at least one of the MN or SN can operate with a shared spectrum channel, and the functionality specified for UE 110 can be used for Integrated Access and Backhaul Mobile Terminal (IAB-MT). Similar to UE 61, IAB-MT can access the network using one network node or two different nodes with Enhanced Dual Connectivity (EN-DC) architecture, New Radio Dual Connectivity (NR-DC) architecture, etc.

[0028] As shown in the figure, UE 110 can also or alternatively connect to access point (AP) 116 via interface 118, which may include an air interface enabling UE 110 to communicatively couple with AP 116. AP 116 may include a wireless local area network (WLAN), a WLAN node, a WLAN termination point, etc. Connection 1207 may include a local wireless connection, such as a connection consistent with any IEEE 702.11 protocol, and AP 116 may include Wi-Fi. ® Router or other access points. Although Figure 1 While not explicitly described, AP 116 can connect to another network (e.g., the Internet) without connecting to RAN 120 or CN 130. In some scenarios, UE 110, RAN 120, and AP 116 can be configured to utilize LTE-WLAN aggregation (LWA) technology or LTE WLAN radio-level technology integrated with IPsec tunneling (LWIP). LWA may involve RAN 120 configuring UE 110, in RRC_CONNECTED state, to utilize LTE and WLAN radio resources. LWIP may involve UE 110 using WLAN radio resources (e.g., connection interface 118) via IPsec protocol tunneling to authenticate and encrypt packets (e.g., Internet Protocol (IP) packets) transmitted through connection interface 118. IPsec tunneling transmission may include encapsulating the entire original IP packet and adding a new packet header to protect the original IP packet header.

[0029] RAN 120 may include one or more RAN nodes 122-1 and 122-2 (collectively referred to as multiple RAN nodes 122, and individually as RAN node 122) enabling the establishment of connections 114-1 and 114-2 between UE 110 and RAN 120. RAN node 122 may also be referred to herein or alternatively as a base station. RAN node 122 may include a network access point configured to provide radio baseband functionality for data and / or voice connectivity between the user and the network based on one or more of the communication technologies described herein (e.g., 2G, 3G, 4G, 5G, WiFi, etc.). Thus, as an example, a RAN node may be an E-UT RAN node B (e.g., an enhanced node B, eNodeB, eNB, 4G base station, etc.), a next-generation base station (e.g., a 5G base station, NR base station, next-generation eNB (gNB), etc.). RAN node 122 may include roadside units (RSUs), transmit / receive points (TRxPs or TRPs), and one or more other types of ground stations (e.g., ground access points). In some scenarios, RAN node 122 may be a dedicated physical device such as a macro cell base station and / or a low-power (LP) base station for providing a smaller coverage area, smaller user capacity, or higher bandwidth compared to a macro cell, such as a femtocell, picocell, or other similar cell. As described below, in some specific implementations, satellite 160 may operate as a base station (e.g., RAN node 122) relative to UE 110. Therefore, references to base stations, RAN node 122, etc. herein may relate to implementations where base stations, RAN node 122, etc., are terrestrial network nodes, and also to implementations where base stations, RAN node 122, etc., are non-terrestrial network nodes (e.g., satellite 160).

[0030] Some or all of the RAN nodes 122 may be implemented as one or more software entities running on a server computer as part of a virtual network, which may be referred to as a centralized RAN (CRAN) and / or a virtual baseband unit pool (vBBUP). In these specific implementations, the CRAN or vBBUP may implement RAN function splitting, such as Packet Data Convergence Protocol (PDCP) splitting, where the Radio Resource Control (RRC) and PDCP layers can be operated by the CRAN / vBBUP, and other Layer 2 (L2) protocol entities can be operated by the individual RAN nodes 122; Medium Access Control (MAC) / Physical (PHY) layer splitting, where the RRC, PDCP, Radio Link Control (RLC), and MAC layers can be operated by the CRAN / vBBUP, and the PHY layer can be operated by the individual RAN nodes 122; or “lower PHY” splitting, where the upper portions of the RRC, PDCP, RLC, MAC, and PHY layers can be operated by the CRAN / vBBUP, and the lower portions of the PHY layer can be operated by the individual RAN nodes 122. This virtualization framework allows the idle processor cores of RAN node 122 to perform or execute other virtualization applications.

[0031] In some implementations, a single RAN node 122 may represent a individual gNB distributed unit (DU) connected to the gNB control unit (CU) via a respective F1 interface. In such implementations, the gNB-DU may include one or more remote radio headers or radio frequency (RF) front-end modules (RFEMs), and the gNB-CU may be operated by a server (not shown) located in RAN 120 or by a server pool (e.g., a group of servers configured to share resources) in a manner similar to CRAN / vBBUP. Alternatively or additionally, one or more nodes in RAN node 122 may be next-generation eNBs (i.e., gNBs) that can provide Evolved Universal Terrestrial Radio Access (E-UTRA) user plane and control plane protocol terminals to UE 110 and can be connected to the 5G core network (5GC) 130 via an NG interface.

[0032] Any of the RAN nodes 122 can serve as the endpoint of the air interface protocol and can be the first point of contact for UE 110. In some implementations, any of the RAN nodes 122 can perform various logical functions of RAN 120, including but not limited to the functions of the Radio Network Controller (RNC), such as radio bearer management, uplink and downlink dynamic radio resource management, data packet scheduling, and mobility management. UE 110 can be configured to communicate with each other or with any of the RAN nodes 122 on a multi-carrier communication channel using Orthogonal Frequency Division Multiplexing (OFDM) communication signals according to various communication technologies, such as, but not limited to, OFDMA communication technologies (e.g., for downlink communication) or single-carrier frequency division multiple access (SC-FDMA) communication technologies (e.g., for uplink and ProSe or sidelink (SL) communication), but the scope of such implementations is not limited in this respect. OFDM signals may include multiple orthogonal subcarriers.

[0033] In some implementations, the downlink resource grid can be used for downlink transmissions from any of the RAN nodes in RAN 122 to UE 110, and uplink transmissions can utilize similar techniques. This grid can be a time-frequency grid (e.g., a resource grid or time-frequency resource grid), representing the physical resources of the downlink in each time slot. Such a time-frequency plane representation is common practice for OFDM systems, making radio resource allocation intuitive. Each column and row of the resource grid corresponds to an OFDM symbol and an OFDM subcarrier, respectively. The duration of the resource grid in the time domain corresponds to a time slot in a radio frame. The smallest time-frequency unit in the resource grid is represented as a resource element. Each resource grid comprises resource blocks that describe the mapping of certain physical channels to resource elements. Each resource block may include a set of resource elements (REs); in the frequency domain, this can represent the minimum amount of resources currently available for allocation. Such resource blocks are used to transmit several different physical downlink channels.

[0034] Furthermore, RAN node 122 can be configured to wirelessly communicate with UE 110 and / or each other via licensed media (also referred to as “licensed spectrum” and / or “licensed bands”), unlicensed shared media (also referred to as “unlicensed spectrum” and / or “unlicensed bands”) or a combination thereof. Licensed spectrum may include channels operating in the frequency range of approximately 400 MHz to approximately 3.8 GHz, while unlicensed spectrum may include a 5 GHz band. Licensed spectrum may correspond to channels or bands selected, reserved, regulated, etc., for certain types of wireless activity (e.g., wireless telecommunications network activity), while unlicensed spectrum may correspond to one or more bands that are unrestricted for certain types of wireless activity. Whether a particular band corresponds to licensed or unlicensed media may depend on one or more factors, such as frequency allocations determined by public sector organizations (e.g., government agencies, regulatory bodies, etc.) or frequency allocations determined by private sector organizations involved in developing wireless communication standards and protocols.

[0035] To operate in unlicensed spectrum, UE 110 and RAN node 122 may use Licensed Assisted Access (LAA), eLAA, and / or feLAA mechanisms. In these specific implementations, UE 110 and RAN node 122 may perform one or more known media sensing or carrier sensing operations to determine whether one or more channels in the unlicensed spectrum are unavailable or otherwise occupied before transmission in the unlicensed spectrum can proceed. Media / carrier sensing operations may be performed according to a Listen-After-Talk (LBT) protocol.

[0036] The LAA mechanism can be built on carrier aggregation (CA) technology in LTE-Advanced systems. In CA, each aggregated carrier is called a component carrier (CC). In some cases, individual CCs may have different bandwidths than other CCs. In Time Division Duplex (TDD) systems, the number of CCs and the bandwidth of each CC may be the same for DL ​​and UL. CA also includes individual serving cells to provide individual CCs. The coverage of serving cells may differ, for example, because CCs on different frequency bands will experience different path losses. The primary serving cell, or PCell, provides the primary component carrier (PCC) for both UL and DL and handles Radio Resource Control (RRC) and Non-Access Plane (NAS) related activities. Other serving cells are called SCells, and each SCell provides a single secondary component carrier (SCC) for both UL and DL. SCCs can be added and removed as needed, while changing the PCC may require UE110 to undergo handover. In LAA, eLAA, and feLAA, some or all of the SCells can operate in unlicensed spectrum (called "LAASCell"), and LAA SCells are assisted by PCells operating in licensed spectrum. When a UE is configured to have more than one LAA SCell, the UE can receive UL authorization on the configured LAA SCell, indicating the start position of different PUSCH within the same subframe.

[0037] The PDSCH can carry user data and higher-layer signaling to UE 110. The Physical Downlink Control Channel (PDCCH) can carry information such as the transmission format and resource allocation related to the PDSCH channel. The PDCCH can also inform UE 110 about the transmission format, resource allocation, and Hybrid Automatic Repeat Request (HARQ) information related to the uplink shared channel. Typically, downlink scheduling (e.g., allocating control and shared channel resource blocks to UE 110-2 within the cell) can be performed on any RAN node in RAN node 122 based on channel quality information fed back from any UE in UE 110. Downlink resource allocation information can be transmitted on the PDCCH used for (e.g., allocated to) each UE in UE 110.

[0038] PDCCH uses Control Channel Elements (CCEs) to convey control information. Many CCEs (e.g., 6, etc.) can be composed of Resource Element Groups (REGs), where REGs are defined as Physical Resource Blocks (PRBs) in OFDM symbols. Before being mapped to resource elements, the complex-valued symbols of the PDCCH can first be organized into quadruplets, which can then be arranged for rate matching, for example, using a sub-block interleaver. One or more of these CCEs can be used to transmit each PDCCH, where each CCE can correspond to nine sets, each with four physical resource elements, called REGs. Four Quadrature Phase Shift Keying (QPSK) symbols can be mapped to each REG. Depending on the DCI size and channel conditions, one or more CCEs can be used to transmit the PDCCH. In LTE, four or more different PDCCH formats with different numbers of CCEs (e.g., aggregation levels, L=1, 2, 4, 8, or 110) can be defined.

[0039] Some implementations may use the concept of resource allocation for control channel information, which is an extension of the concept described above. For example, some implementations may utilize an extended (E)-PDCCH that uses PDSCH resources for control information transmission. One or more ECCEs may be used to transmit the EPDCCH. Similarly, each ECCE may correspond to a set of nine, each consisting of four physical resource elements, called an EREG. In some cases, an ECCE may have a different number of EREGs.

[0040] RAN nodes 122 can be configured to communicate with each other via interface 123. In a specific implementation where exemplary network 100 is an LTE system, interface 123 may be an X2 interface. This X2 interface may be defined between two or more RAN nodes 122 (e.g., two or more eNBs / gNBs or combinations thereof) connected to the Evolved Packet Core (EPC) or CN 130, and / or between two eNBs connected to the EPC. In some implementations, the X2 interface may include an X2 user plane interface (X2-U) and an X2 control plane interface (X2-C). X2-U may provide flow control mechanisms for user data packets transmitted via the X2 interface and may be used to transmit information regarding the delivery of user data between eNBs or gNBs. For example, X2-U can provide specific sequence number information about user data transmitted from the primary eNB (MeNB) to the secondary eNB (SeNB); information about the successful in-order delivery of PDCP Packet Data Units (PDUs) from the SeNB to the UE 110 for user data; information about PDCP PDUs not delivered to the UE 110; information about the current minimum expected buffer size at the SeNB for transmitting user data to the UE; and so on. X2-C can provide in-LTE access mobility functions (e.g., including context transfer from the source eNB to the target eNB, user plane transmission control, etc.), load management functions, and inter-cell interference coordination functions.

[0041] As shown in the figure, RAN 120 can be connected (e.g., communicatively coupled) to CN 130. CN 130 may include multiple network elements 132 configured to provide various data and telecommunications services to customers / subscribers (e.g., users of UE 110) connected to CN 130 via RAN 120. In some implementations, CN 130 may include an evolved packet core (EPC), a 5G CN, and / or one or more additional or alternative types of CNs. Components of CN 130 may be implemented in a physical node or separate physical nodes, including components for reading and executing instructions from machine-readable or computer-readable media (e.g., non-transitory machine-readable storage media). In some implementations, network function virtualization (NFV) may be used to virtualize any or all of the aforementioned network node roles or functions via executable instructions stored in one or more computer-readable storage media (described in further detail below). A logical example of CN 130 may be referred to as a network slice, and a logical example of a portion of CN 130 may be referred to as a network subslice. Network Functions Virtualization (NFV) architectures and infrastructures can be used to virtualize one or more network functions onto physical resources that include a combination of industry-standard server hardware, storage hardware, or switches (or alternatively, be performed by proprietary hardware). In other words, NFV systems can be used to perform virtual or reconfigurable concrete implementations of one or more EPC components / functions.

[0042] As shown in the figure, CN 130, application server (AS) 140, and external network 150 can be interconnected via interfaces 134, 136, and 138, which may include IP network interfaces. Application server 140 may include one or more server devices or network elements (e.g., virtual network functions (VNFs) that provide applications using IP bearer resources through CN 130 (e.g., UMTS PS domain, LTE PS data service, etc.). Application server 140 may also be configured, or alternatively, to support one or more communication services of UE 110 via CN 130 (e.g., VoIP sessions, push-to-talk (PTT) sessions, group communication sessions, social networking services, etc.). Similarly, external network 150 may include one or more of various networks, including the Internet, thereby providing network access to various additional services, information, interconnectivity, and other network features to the mobile communication network and UE 110.

[0043] As shown in the figure, exemplary network 100 may include an NTN that may include one or more satellites 160-1 and 160-2 (collectively, "Satellite 160"). Satellite 160 may communicate with UE 110 via a serving link or radio interface 162 and / or with RAN 120 via a feed link or radio interface 164 (depicted separately as 164-1 and 164). In some implementations, Satellite 160 may operate as a passive or transparent network relay node regarding communication between UE 110 and a terrestrial network (e.g., RAN 120). In some implementations, Satellite 160 may operate as an active or regenerative network node, such that Satellite 160 may operate as a base station to UE 110 (e.g., as a gNB of RAN 120) regarding communication between UE 110 and RAN 120. In some implementations, satellite 160 may communicate with each other via a direct radio interface (e.g., 166) or an indirect radio interface (e.g., via RAN 120 using interfaces 164-1 and 164-2). Alternatively, satellite 160 may include a GEO satellite, a LEO satellite, or another type of satellite. Satellite 160 may also, or alternatively, relate to one or more satellite systems or architectures, such as Global Navigation Satellite System (GNSS), Global Positioning System (GPS), Global Navigation Satellite System (GLONASS), BeiDou Navigation Satellite System (BDS), etc. In some implementations, satellite 160 may operate as a base station (e.g., RAN node 122) relative to UE 110. Therefore, references herein to base stations, RAN node 122, etc., may relate to implementations where base stations, RAN node 122, etc., are terrestrial network nodes, and to implementations where base stations, RAN node 122, etc., are non-terrestrial network nodes (e.g., satellite 160).

[0044] Figure 2 This is a timeline diagram of example 200 for secondary cell activation using a UE-specific RS. As shown, example 200 includes timeline 210 and corresponding SSBs 220-1, 220-2...SSB 220-3 (collectively referred to as "SSB 220"). UE 110-1 can receive and process activation commands following SSB 220-1 at 230. In a specific implementation where the network has not yet configured TRS (e.g., the PCell has not yet provided UE 110-1 with the SCell's TRS configuration), UE 110-1 can perform fine-grained time tracking based on the first complete SSB 220-2 corresponding to the TCI state received by UE 110-1.

[0045] In contrast, in specific implementations where the network has already configured TRS (e.g., the PCell has provided the SCell's TRS configuration to UE 110-1), UE 110-1 can perform fine-grained time tracking based on TRS 240 from the SCell. As described herein, the TRS configuration can be periodic or aperiodic. In Example 200, if the TRS configuration is periodic, then DELTA_T 250 (e.g., Time_FineTiming) is the periodicity of the TRS configuration. Conversely, if the TRS configuration is aperiodic, then DELTA_T 250 (e.g., Time_FineTiming) can be the duration between the UE completing the processing of the last activation command for the PDCCH TCI and PDSCH TCI (where applicable) and the timing of the first fully available TRS 240. Therefore, the techniques described herein enable fine-grained time tracking based on SSB, periodic TRS, or aperiodic TRS.

[0046] Figure 3 This is a flowchart of an exemplary procedure 300 for activating a secondary cell using a UE-specific RS. Procedure 300 can be implemented by UE 110. In some specific implementations, some or all of procedure 300 can be implemented by one or more other systems or devices (including...). Figure 1 (One or more of the devices) are used for execution. Additionally, process 300 may include... Figure 3 The operations shown are fewer, additional, differently ordered, and / or arranged compared to one or more. Furthermore, due to... Figure 3 The corresponding description discusses an exemplary procedure 300 for activating a secondary cell that can be performed by UE 110; therefore, the scope of the technology described herein includes that which can be performed by a corresponding base station (e.g., RAN node 112), satellite, and / or reference. Figure 1 The corresponding processes performed by the other network devices.

[0047] As shown in the figure, process 300 may include receiving the TRS configuration of the SCell from the PCell during the RRC configuration process (box 310). For example, a base station operating as the PCell of UE 110 may provide UE 110 with the TRS configuration of another base station intended to operate as the SCell of UE 110. As described herein, the TRS configuration may include a TRS during which UE 110 may synchronize with the SCell based on a UE-specific RS (e.g., perform fine time tracking). In some implementations, UE 110 may also receive other types of configuration information about the SCell, such as SMTC information, TCI information, etc. In some implementations, UE 110 may receive another MAC command or DCI message indicating the TRS configuration (e.g., TRS transmission). In some implementations, when no TRS configuration is provided, UE 110 may receive the SMTC and / or TCI of the SCell and perform fine time tracking based on the SSB of the SCell.

[0048] Procedure 300 may also include receiving an SCell activation message and performing cell search and ADC (Activation Control Function) for the SCell (block 320). For example, UE 110 may receive a MAC CE including an activation command for the SCell from the PCell. In some implementations, the activation command may correspond to a carrier on the SCell. The carrier on the SCell may be part of UE 110's CA configuration (which may include one or more carriers of the PCell). In response to the activation command, UE 110 may perform cell search and AGC for the SCell.

[0049] Process 300 may include determining whether a periodic or aperiodic TRS applies to the SCell based on the TRS configuration (block 330). For example, UE 110 may determine whether the SCell implements a periodic or aperiodic TRS based on the TRS configuration received from the PCell. UE 110 may also, or alternatively, determine the transmission time of the TRS based on the TRS configuration.

[0050] Process 300 may include performing fine-tuning time tracking and / or AGC based on the periodicity of the TRS when periodicity applies to the TRS (box 340). For example, UE 110 may perform fine-tuning time tracking and / or AGC based on the periodicity of the TRS. As described herein, when UE 110 performs fine-tuning time tracking and / or AGC based on the periodicity of the TRS, Time_FineTiming may be equal to the periodicity of the PRS.

[0051] Procedure 300 may include determining, when aperiodicity applies, whether a TCI command has been configured for the SCell (block 350). For example, when aperiodicity applies to TRS, UE 110 may determine whether a TCI command has been configured for the SCell. In some implementations, as part of the RRC configuration procedure, the TCI status may be provided to UE 110, and the PCell may send the TCI command to UE 110 from a MAC CE (which may be the same or a different MAC CE for the SCell activation command).

[0052] Process 300 may further include performing fine time tracking and / or AGC (box 360) after the TCI command is decoded when the TRS aperiodicity and TCI configuration are applicable to SCell activation. For example, when the SCell uses TRS aperiodicity, UE 110 may determine whether a TCI command regarding SCell activation has been received, and if so, perform fine time tracking during the TRS period after the TCI command is decoded by UE 110.

[0053] Procedure 300 may include performing fine time tracking and / or AGC (box 370) during the TRS period after slot N + (T_HARQ + 3ms) / (NR slot length) when the TRS is aperiodic but no TCI command is configured. For example, when UE 110 determines that the TRS is aperiodic but no TCI command is configured for SCell activation, UE 110 may perform fine time tracking during the TRS period that occurs after slot N + (T_HARQ + 3ms) / (NR slot length).

[0054] Figure 4 This is a sequence diagram of an exemplary procedure 400 for activating a secondary cell using a UE-specific RS. As shown, the exemplary procedure 400 may involve UE 110, base station 122-1 (as a PCell operation connected to UE 110), and base station 122-2 (as an SCell operation of UE 110). In some specific implementations, the exemplary procedure 400 may include... Figure 4 The examples shown are those compared to one or more additional, alternative, fewer, or different arrangements of operation and / or equipment. Additionally, although... Figure 4 The operation is described as being performed by UE 110, base station 122-1 and base station 122-2, but in some specific implementations, one or more of these operations may be performed by another device or combination of devices in the wireless communication network.

[0055] As shown in the figure, base station 122-1 and UE 110 can participate in RRC procedures, such as the RRC connection reconfiguration procedure (at 402). During this procedure, base station 122-1 can provide UE 110 with the TRS configuration of a SCell (e.g., base station 122-2). At some point, base station 122-1 can send a MAC CE to UE 110, which may include a command for activating base station 122-2 as a SCell for UE 110 (at 404). This activation command may include the TRS configuration of base station 122-2. In some embodiments, the MAC CE may also include a TCI command for base station 122-2 or another type of TCI. In some embodiments, the TCI command may be sent in a different MAC CE. In still other embodiments, the TCI command may not be sent.

[0056] In response to the activation command, UE 110 may initiate cell search and AGC adjustment regarding base station 122-2 (at 406). Additionally, UE 110 may determine the TRS configuration of base station 122-2 (at 408). The TRS configuration may indicate a UE-specific RS, which can be used by UE 110 for synchronization with base station 122-2 (e.g., performing fine time tracking). In some implementations, this may include UE 110 determining whether the TRS of base station 122-2 is periodic or aperiodic. In some implementations, such as in a scenario where a TCI command is sent, UE 110 may also determine the TCI configuration of base station 122-2. In some implementations, base station 122-1 may transmit a TRS trigger to UE 110, which may cause or prompt UE 110 regarding the TRS (e.g., initiating fine time tracking during the TRS) (at 410). In some implementations, the TRS trigger may be part of a MAC command. In some implementations, the TRS may be part of a DCI. In some specific implementations, the PCell can transmit the TRS trigger at another time, such as before or at the same time as the UE 110 determines the TRS configuration.

[0057] As shown in the figure, UE 110 can perform fine-grained time tracking based on the TRS configuration of base station 122-2. As mentioned above, this can depend in part on whether the TRS is periodic or aperiodic. Also, as described herein, in some implementations, fine-grained time tracking can also be based on the TCI configuration of base station 122-2 and when UE 110 processes TCI commands. UE 110 can continue by completing SCell activation with respect to base station 122-2, which may later lead to a CA scenario involving UE 110, base station 122-1, and base station 122-2.

[0058] Figure 5This is a diagram illustrating examples of components of a device according to one or more embodiments described herein. In some embodiments, device 500 may include application circuitry 502, baseband circuitry 504, radio frequency (“RF”) circuitry 506, front-end module (“FEM”) circuitry 508, one or more antennas 56, and power management circuitry (“PMC”) 512 (at least coupled together as shown). Components of the illustrated device 500 may be included in a UE or RAN node. In some embodiments, device 500 may include fewer components (e.g., the RAN node may not utilize application circuitry 502, but instead include a processor / controller to process IP data received from a CN such as a 5GC 130 or an evolved packet core (EPC). In some embodiments, device 500 may include additional components such as memory / storage devices, displays, cameras, sensors (including one or more temperature sensors, such as a single temperature sensor, multiple temperature sensors at different locations in device 500, etc.), or input / output (I / O) interfaces. In other implementations, the following components may be included in more than one device (e.g., the circuitry may be individually included in more than one device for a cloud-RAN (C-RAN) implementation).

[0059] Application circuitry 502 may include one or more application processors. For example, application circuitry 502 may include circuitry such as, but not limited to, one or more single-core or multi-core processors. The processor may include any combination of general-purpose processors and special-purpose processors (e.g., graphics processors, application processors, etc.). The processor may be coupled to or may include a memory / storage device and may be configured to execute instructions stored in the memory / storage device to enable various applications or operating systems to run on device 500. In some specific implementations, the processor of application circuitry 502 may process IP data packets received from the EPC.

[0060] Baseband circuitry 504 may include circuitry such as, but not limited to, one or more single-core or multi-core processors. Baseband circuitry 504 may include one or more baseband processors or control logic to process baseband signals received from the receive signal path of RF circuitry 506 and generate baseband signals for the transmit signal path of RF circuitry 506. Baseband processing circuitry 504 may interact with application circuitry 502 to generate and process baseband signals and control the operation of RF circuitry 506. For example, in some implementations, baseband circuitry 504 may include a third-generation (3G) baseband processor 504A, a fourth-generation (4G) baseband processor 504B, a fifth-generation (5G) baseband processor 504C, or other existing, under development, or future generations of baseband processors 504D (e.g., second-generation (2G), sixth-generation (6G), etc.). Baseband circuitry 504 (e.g., one or more baseband processors 504A-504D) may handle various radio control functions that can communicate with one or more radio networks via RF circuitry 506. In other embodiments, some or all of the functions of the baseband processors 504A-504D may be included in modules stored in memory 504G and executed via a central processing unit (CPU) 504E. Radio control functions may include, but are not limited to, signal modulation / demodulation, encoding / decoding, and radio frequency shifting. In some embodiments, the modulation / demodulation circuitry of the baseband circuitry 504 may include Fast Fourier Transform (FFT), precoding, or constellation mapping / demapping functions. In some embodiments, the encoding / decoding circuitry of the baseband circuitry 504 may include convolution, tail-biting convolution, turbo, Viterbi, or low-density parity-check (LDPC) encoder / decoder functions. Specific implementations of the modulation / demodulation and encoder / decoder functions are not limited to these examples and may include other suitable functions in other respects.

[0061] In some embodiments, the baseband circuitry 504 may include one or more audio digital signal processors (DSPs) 504F. The audio DSP 504F may include elements for compression / decompression and echo cancellation, and in other embodiments may include other suitable processing elements. In some embodiments, components of the baseband circuitry may be suitably combined in a single chip, a single chipset, or disposed on the same circuit board. In some embodiments, some or all components of the baseband circuitry 504 and the application circuitry 502 may be implemented together, such as (e.g.) on a system-on-a-chip (SoC).

[0062] In some implementations, baseband circuit 504 can provide communication compatible with one or more radio technologies. For example, in some implementations, baseband circuit 504 can support communication with NG-RAN, Evolved Universal Terrestrial Radio Access Network (EUTRAN), or other Wireless Metropolitan Area Networks (WMAN), Wireless Local Area Networks (WLAN), Wireless Personal Area Networks (WPAN), etc. Implementations in which baseband circuit 504 is configured to support radio communication with more than one radio protocol may be referred to as multimode baseband circuits.

[0063] RF circuit 506 can communicate with a wireless network using modulated electromagnetic radiation over a non-solid medium. In various embodiments, RF circuit 506 may include switches, filters, amplifiers, etc., to facilitate communication with the wireless network. RF circuit 506 may include a receive signal path that includes circuitry for down-converting the RF signal received from FEM circuit 508 and providing a baseband signal to baseband circuit 504. RF circuit 506 may also include a transmit signal path that includes circuitry for up-converting the baseband signal provided by baseband circuit 504 and providing an RF output signal to FEM circuit 508 for transmission.

[0064] In some embodiments, the receive signal path of RF circuit 506 may include mixer circuit 506a, amplifier circuit 506b, and filter circuit 506c. In some embodiments, the transmit signal path of RF circuit 506 may include filter circuit 506c and mixer circuit 506a. RF circuit 506 may also include synthesizer circuit 506d for synthesizing the frequency used by mixer circuit 506a in both the receive and transmit signal paths. In some embodiments, mixer circuit 506a in the receive signal path may be configured to down-convert the RF signal received from FEM circuit 508 based on the synthesized frequency provided by synthesizer circuit 506d. Amplifier circuit 506b may be configured to amplify the down-converted signal, and filter circuit 506c may be a low-pass filter (LPF) or band-pass filter (BPF) configured to remove unwanted signals from the down-converted signal to generate an output baseband signal. The output baseband signal may be provided to baseband circuit 504 for further processing. In some implementations, the output baseband signal may be a zero-frequency baseband signal, but this is not required. In some implementations, the mixer circuit 506a in the receiving signal path may include a passive mixer, but the scope of implementation is not limited in this respect.

[0065] In some implementations, the mixer circuit 506a of the transmit signal path can be configured to up-convert the input baseband signal based on the synthesized frequency provided by the synthesizer circuit 506d to generate an RF output signal for the FEM circuit 508. The baseband signal can be provided by the baseband circuit 504 and can be filtered by the filter circuit 506c.

[0066] In some embodiments, the mixer circuit 506a for the receive signal path and the mixer circuit 506a for the transmit signal path may include two or more mixers, and may be arranged for quadrature down-conversion and up-conversion, respectively. In some embodiments, the mixer circuit 506a for the receive signal path and the mixer circuit 506a for the transmit signal path may include two or more mixers, and may be arranged for image suppression (e.g., Hartley image suppression). In some embodiments, the mixer circuit 506a for the receive signal path and the mixer circuit 506a for the transmit signal path may be arranged for direct down-conversion and direct up-conversion, respectively. In some embodiments, the mixer circuit 506a for the receive signal path and the mixer circuit 506a for the transmit signal path may be configured for superheterodyne operation.

[0067] In some embodiments, the output baseband signal and the input baseband signal may be analog baseband signals, although the scope of the embodiments is not limited in this respect. In some alternative embodiments, the output baseband signal and the input baseband signal may be digital baseband signals. In these alternative embodiments, RF circuit 506 may include analog-to-digital converter (ADC) and digital-to-analog converter (DAC) circuitry, and baseband circuit 504 may include a digital baseband interface for communication with RF circuit 506.

[0068] In some dual-mode implementations, separate radio IC circuits can be provided to process signals for each spectrum, but the scope of implementations is not limited in this respect.

[0069] In some specific implementations, synthesizer circuit 506d can be a fractional-N synthesizer or a fractional-N / N+1 synthesizer, but the scope of implementation is not limited in this respect, as other types of frequency synthesizers may also be suitable. For example, synthesizer circuit 506d can be a Δ-∑ synthesizer, a frequency multiplier, or a synthesizer including a phase-locked loop with a frequency divider.

[0070] Synthesizer circuit 506d can be configured to synthesize an output frequency based on the frequency input and the divider control input for use by mixer circuit 506a of RF circuit 506. In some specific implementations, synthesizer circuit 506d can be a fractional N / N+1 synthesizer.

[0071] In some implementations, the frequency input may be provided by a voltage-controlled oscillator (VCO), although this is not mandatory. The divider control input may be provided by the baseband circuit 504 or the application processor 502 according to the desired output frequency. In some implementations, the divider control input (e.g., N) may be determined from a lookup table based on the channel indicated by the application processor 502.

[0072] The synthesizer circuit 506d of the RF circuit 506 may include a frequency divider, a delay-locked loop (DLL), a multiplexer, and a phase accumulator. In some embodiments, the frequency divider may be a dual-mode divider (DMD), and the phase accumulator may be a digital phase accumulator (DPA). In some embodiments, the DMD may be configured to divide the input signal by N or N+1 (e.g., based on carry output) to provide a fractional division ratio. In some exemplary embodiments, the DLL may include a cascaded, tunable delay element, a phase detector, a charge pump, and a set of D-type flip-flops. In these embodiments, the delay elements may be configured to divide the VCO period into Nd equal phase groups, where Nd is the number of delay elements in the delay line. Thus, the DLL provides negative feedback to help ensure that the total delay through the delay line is one VCO period.

[0073] In some embodiments, synthesizer circuit 506d may be configured to generate a carrier frequency as the output frequency, while in other embodiments, the output frequency may be a multiple of the carrier frequency (e.g., twice the carrier frequency, four times the carrier frequency) and may be used in conjunction with quadrature generator and frequency divider circuitry to generate multiple signals having multiple different phases relative to each other at that carrier frequency. In some embodiments, the output frequency may be the LO frequency (fLO). In some embodiments, RF circuit 506 may include an IQ / polarity converter.

[0074] FEM circuit 508 may include a receive signal path, which may include circuitry configured to operate on RF signals received from one or more antennas 56, amplify the received signals, and provide an amplified version of the received signals to RF circuit 506 for further processing. FEM circuit 508 may also include a transmit signal path, which may include circuitry configured to amplify transmit signals provided by RF circuit 506 for transmission through one or more of the one or more antennas 56. In various specific embodiments, amplification via the transmit or receive signal path may be performed only in RF circuit 506, only in FEM 508, or in both RF circuit 506 and FEM 508.

[0075] In some implementations, FEM circuit 508 may include a TX / RX switch to switch between transmit and receive mode operation. The FEM circuit may include a receive signal path and a transmit signal path. The receive signal path of the FEM circuit may include an LNA to amplify the received RF signal and provide the amplified received RF signal as an output (e.g., provided to RF circuit 506). The transmit signal path of FEM circuit 508 may include a power amplifier (PA) to amplify the input RF signal (e.g., provided by RF circuit 506), and one or more filters to generate an RF signal for subsequent transmission (e.g., through one or more antennas in one or more antennas 56).

[0076] In some implementations, the PMC 512 can manage the power supplied to the baseband circuitry 504. Specifically, the PMC 512 can control power selection, voltage scaling, battery charging, or DC-DC conversion. The PMC 512 is typically included when the device 500 can be battery powered, for example, when the device is included in a UE. The PMC 512 can improve power conversion efficiency while providing the desired implementation size and thermal characteristics.

[0077] Although Figure 5 The PMC 512 is shown coupled only to the baseband circuit 504. However, in other specific implementations, the PMC 512 may be additionally or alternatively coupled to other components, such as, but not limited to, the application circuit 502, the RF circuit 506, or the FEM 508, and perform similar power management operations.

[0078] In some implementations, the PMC 512 can control or otherwise become part of various power-saving mechanisms of the device 500. For example, if the device 500 is in the RRC_Connected state, where the device is still connected to the RAN node because it expects to receive traffic immediately, it can enter a state called Discontinuous Receive Mode (DRX) after a period of inactivity. During this state, the device 500 can be powered down for short intervals, thereby saving power.

[0079] If there is no data traffic activity during the extended period, device 500 can transition to the RRC_Idle state, in which the device disconnects from the network and does not perform operations such as channel quality feedback or handover. Device 500 enters a very low power state and performs paging, in which the device periodically wakes up again to listen to the network, and then powers off again. Device 500 may not receive data in this state; to receive data, the device can transition back to the RRC_Connected state.

[0080] An additional power-saving mode allows the device to be unavailable from the network for periods exceeding the paging interval (ranging from seconds to hours). During this time, the device is completely unconnected to the network and can be completely powered off. Any data sent during this period will incur significant latency, which is assumed to be acceptable.

[0081] The processors of application circuit 502 and baseband circuit 504 can be used to execute elements of one or more instances of the protocol stack. For example, the processor of baseband circuit 504 can be used alone or in combination to perform layer 3, layer 2, or layer 1 functions, while the processor of application circuit 502 can utilize data received from these layers (e.g., packet data) and further perform layer 4 functions (e.g., Transport Communication Protocol (TCP) and User Datagram Protocol (UDP) layers). As mentioned herein, layer 3 may include the Radio Resource Control (RRC) layer, which will be described in further detail below. As mentioned herein, layer 2 may include the Media Access Control (MAC) layer, the Radio Link Control (RLC) layer, and the Packet Data Convergence Protocol (PDCP) layer, which will be described in further detail below. As mentioned herein, layer 1 may include the physical (PHY) layer of the UE / RAN node, which will be described in further detail below.

[0082] Figure 6 This is a diagram of an exemplary interface of a baseband circuit according to one or more specific embodiments described herein. As discussed above, Figure 5 The baseband circuit 504 may include processors 504A-904E and memory 504G utilized by the processors. Each of the processors 504A-204E may include a memory interface 604A-604E for sending / receiving data to / from memory 504G.

[0083] Baseband circuit 504 may further include: one or more interfaces for communicatively coupling to other circuits / devices, such as memory interface 612 (e.g., an interface for sending / receiving data to / from a memory external to baseband circuit 504); application circuit interface 614 (e.g., for sending / receiving data to / from a memory external to baseband circuit 504); and application circuit interface 614 (e.g., for sending / receiving data to / from a memory external to baseband circuit 504). Figure 5 Application circuit 502 is an interface for sending / receiving data; RF circuit interface 616 (e.g., for sending / receiving data to / from...). Figure 5 RF circuit 506 is an interface for transmitting / receiving data; wireless hardware connection interface 618 (e.g., for sending / receiving data to / from near field communication (NFC) components, Bluetooth). ® Components (e.g., Bluetooth) ® Low power consumption, Wi-Fi ®Interfaces for sending / receiving data to / from components and other communication components); and power management interface 620 (e.g., an interface for sending / receiving power or control signals to / from PMC 512).

[0084] Examples in this document may include subjects such as methods, components for performing actions or blocks of methods, and at least one machine-readable medium including executable instructions that, when executed by a machine (e.g., a processor with memory, an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), etc.), cause the machine to perform actions of a method, apparatus, or system of concurrent communication using various communication technologies according to the specific implementations and examples described.

[0085] In Embodiment 1, a User Equipment (UE) device may include: a radio frequency (RF) circuit configured to communicate with a wireless communication network; a memory device configured to store instructions; and one or more processors connected to the RF circuit and the memory device, and configured to execute the instructions to: receive a Tracking Reference Signal (TRS) configuration via the RF circuit and from a first carrier of a first base station operating as a primary cell of the UE, the TRS configuration indicating a UE-specific Reference Signal (RS) corresponding to a second carrier of the first base station or a third carrier of a second base station designated as a secondary cell of the UE; receive an activation command for the secondary cell from the primary cell via the RF circuit; and, in response to the activation command, perform a secondary cell activation process with respect to the second base station, the secondary cell activation process including fine time tracking based on the UE-specific RS.

[0086] In Embodiment 2, the one or more processors are configured to: determine the periodicity of the UE-specific RS based on the TRS configuration; and perform fine time tracking according to the periodicity of the UE-specific RS. In Embodiment 3, the one or more processors are configured to: determine that the UE-specific RS is an aperiodic RS based on the TRS configuration; and perform fine time tracking based on the transmission time of the activation command. In Embodiment 4, the fine time tracking is performed based on the duration associated with the Hybrid Automatic Repeat Request (HARQ) message associated with the activation command.

[0087] In Embodiment 5, the one or more processors are configured to: detect a TRS trigger based on a Media Access Control (MAC) command or Downlink Control Information (DCI); and perform fine time tracking in response to the TRS trigger. In Embodiment 6, the one or more processors are configured to: determine that the UE-specific RS is an aperiodic RS based on the TRS configuration; determine that a Transport Configuration Indicator (TCI) command has been received; and perform fine time tracking after decoding the TCI command. In Embodiment 7, the one or more processors are configured to perform fine time tracking and Automatic Gain Control (AGC) during the transmission of the UE-specific RS. In Embodiment 8, the one or more processors are configured to receive the TRS configuration during a Radio Resource Control (RRC) procedure involving the first base station. In Embodiment 9, the one or more processors are configured to perform fine time tracking based on a cell-specific RS when the TRS configuration is not received.

[0088] In Embodiment 10, a baseband (BB) circuit for a user equipment (UE) includes circuitry for: receiving a tracking reference signal (TRS) configuration from a first carrier of a first base station operating as a primary cell of the UE, the TRS configuration indicating a UE-specific reference signal (RS) corresponding to a second carrier of the first base station or a third carrier of a second base station designated as a secondary cell of the UE; receiving an activation command for the secondary cell from the primary cell; and, in response to the activation command, performing a secondary cell activation process with respect to the second base station, the secondary cell activation process including fine time tracking based on the UE-specific RS. In Embodiments 11 to 18, the BB circuit of Embodiment 10 is further modified by applying one or more or any combination of device features from Embodiments 2 to 9 as BB circuit features of Embodiment 10.

[0089] In Embodiment 19, a method performed by a User Equipment (UE) may include: receiving a Tracking Reference Signal (TRS) configuration from a first carrier of a first base station operating as a primary cell of the UE, the TRS configuration indicating a UE-specific Reference Signal (RS) corresponding to a second carrier of the first base station or a third carrier of a second base station designated as a secondary cell of the UE; receiving an activation command for the secondary cell from the primary cell; and, in response to the activation command, performing a secondary cell activation procedure with respect to the second base station, the secondary cell activation procedure including fine time tracking based on the UE-specific RS. In Embodiments 20 to 27, the method of Embodiment 19 is further modified by applying one or more or any combination of features from Embodiments 2 to 9 as method features of Embodiment 19.

[0090] As in Embodiment 28, a User Equipment (UE) device may include means for receiving a Tracking Reference Signal (TRS) configuration from a first carrier of a first base station operating as a primary cell of the UE, the TRS configuration indicating a UE-specific Reference Signal (RS) corresponding to a second carrier of the first base station or a third carrier of a second base station designated as a secondary cell of the UE; means for receiving an activation command for the secondary cell from the primary cell; and means for performing a secondary cell activation process with respect to the second base station in response to the activation command, the secondary cell activation process including fine time tracking based on the UE-specific RS. In Embodiments 29 to 36, the UE of Embodiment 28 is further modified by applying one or more or any combination of features from Embodiments 2 to 9 as features of Embodiment 28 (e.g., means for the features).

[0091] In embodiment 37, a computer-readable medium includes instructions that, when executed by a processor, cause the processor to: receive a tracking reference signal (TRS) configuration from a first carrier of a first base station operating as a primary cell of the UE, the TRS configuration indicating a UE-specific reference signal (RS) corresponding to a second carrier of the first base station or a third carrier of a second base station designated as a secondary cell of the UE; receive an activation command for the secondary cell from the primary cell; and, in response to the activation command, perform a secondary cell activation process with respect to the second base station, the secondary cell activation process including fine time tracking based on the UE-specific RS. In embodiments 38 to 45, the computer-readable medium of embodiment 37 is further modified by applying one or more or any combination of the device features of embodiments 2 to 9 as the computer-readable medium features of embodiment 37.

[0092] The above description of illustrative examples, embodiments, aspects, etc., of the subject matter of this disclosure, including the content described in the specification summary, is not intended to be exhaustive or to limit the disclosed aspects to the precise form disclosed. While specific examples, embodiments, aspects, etc., have been described herein for illustrative purposes, various modifications may be considered within the scope of such examples, embodiments, aspects, etc., as will be appreciated by those skilled in the art.

[0093] In this regard, although the subject matter of this disclosure has been described in conjunction with various examples, embodiments, aspects, and corresponding drawings, it should be understood, where applicable, that other similar aspects may be used or that modifications and additions may be made to the disclosed subject matter to perform the same, similar, alternative, or substitute functions without departing from the disclosed subject matter. Therefore, the disclosed subject matter should not be limited to any single example, embodiment, or aspect described herein, but should be interpreted in accordance with the breadth and scope of the appended claims.

[0094] In particular, regarding the various functions performed by the aforementioned components or structures (components, devices, circuits, systems, etc.), unless otherwise stated, the terminology used to describe such components (including references to "component") is intended to correspond to any component or structure that performs the specified function of the said component (e.g., functionally equivalent), even if it is not structurally equivalent to the disclosed structure that performs the function in the exemplary embodiments shown herein. Furthermore, while certain features have been disclosed with respect to only one of the plurality of embodiments, it may be desirable and advantageous for any given or particular application to combine such features with one or more other features of other embodiments.

[0095] As used herein, the term “or” is intended to mean an inclusive “or” rather than an exclusive “or.” That is, unless otherwise stated or clearly apparent from the context, “X adopts A or B” is intended to mean any natural inclusive arrangement. That is, “X adopts A or B” is satisfied if X adopts A; X adopts B; or X adopts both A and B. Additionally, the articles “a” and “an” used in this application and the appended claims should generally be interpreted as meaning “one or more” unless otherwise stated or clearly apparent from the context to refer to the singular form. Furthermore, to the extent that the terms “comprising,” “including,” “having,” “having,” “with,” or variations thereof are used in the Detailed Description and claims, such terms are intended to be included in a manner similar to the term “comprising.” Furthermore, in the context of discussing one or more numbered items (e.g., “first X,” “second X,” etc.), generally, the one or more numbered items may be different or they may be the same, but in some cases, the context may indicate that they are different or that they are the same.

[0096] As is widely recognized, the use of personally identifiable information should comply with privacy policies and practices that are generally accepted to meet or exceed industry or governmental requirements for protecting user privacy. Specifically, personally identifiable information data should be managed and processed to minimize the risk of unintentional or unauthorized access or use, and the nature of authorized use should be clearly explained to users.

Claims

1. A baseband processor for a user equipment (UE), the baseband processor being configured to perform operations when executing instructions stored in a memory, the operations including: Receive tracking reference signal (TRS) configuration to configure aperiodic TRS; Receive secondary cell activation command; as well as In response to receiving the secondary cell activation command and the TRS configuration, the secondary cell activation process is initiated based on the timing between the timing of the secondary cell activation command and the timing of the first fully available TRS.

2. The baseband processor according to claim 1, wherein the operation further includes: The TRS configuration is received during the Radio Resource Control (RRC) procedure.

3. The baseband processor of claim 1, wherein the timing between the secondary cell activation command and the timing of the first fully available TRS timing includes: The time between the UE completing the processing of the activation command for the Physical Downlink Control Channel (PDCCH) Transmission Configuration Indicator (TCI) or the Physical Downlink Shared Channel (PDSCH) TCI and the timing of the first fully available TRS opportunity.

4. The baseband processor of claim 3, wherein the first fully available TRS timing is the first fully available TRS timing of the non-periodic TRS.

5. The baseband processor of claim 3, wherein the first fully available TRS timing has the same TCI state as the PDCCH TCI or the PDSCH TCI.

6. The baseband processor of claim 1, wherein the aperiodic TRS is used to perform fine time tracking, and wherein the secondary cell activation process is based on the fine time tracking.

7. The baseband processor of claim 1, wherein the aperiodic TRS is used to perform automatic gain control (AGC), and wherein the secondary cell activation process is based on the AGC.

8. The baseband processor of claim 1, wherein the timing between the secondary cell activation command and the first full availability TRS timing is based on the timing of the Hybrid Automatic Repeat Request (HARQ) message associated with the secondary cell activation command.

9. The baseband processor of claim 8, wherein the timing between the secondary cell activation command and the timing of the first fully available TRS timing is further based on an offset of 3 milliseconds (ms) and a new air interface NR slot length specified for performing fine time tracking.

10. The baseband processor according to claim 8, wherein the secondary cell activation command includes a Media Access Control (MAC) control element (CE).

11. A method for a user equipment (UE), the method comprising: Receive UE-specific reference signal configuration to configure non-periodic UE-specific reference signals; Receive secondary cell activation command; as well as In response to receiving the secondary cell activation command and the UE-specific reference signal configuration, a secondary cell activation process is initiated based on the timing between the timing of the secondary cell activation command and the timing of the first fully available UE-specific reference signal.

12. The method of claim 11, further comprising: Receive Transport Configuration Indicator (TCI) command; as well as After decoding the TCI command, fine time tracking is performed during the UE-specific reference signal; The secondary cell activation process is based on the fine time tracking.

13. The method of claim 12, wherein the TCI command is included in the Media Access Control (MAC) control element (CE).

14. The method of claim 13, wherein the MAC CE further includes the secondary cell activation command.

15. A user equipment (UE), comprising: Radio frequency (RF) circuits; as well as A processor, coupled to the RF circuit, is configured to cause the UE to: when executing instructions stored in memory. Receive tracking reference signal (TRS) configuration to configure aperiodic TRS; Receive secondary cell activation command; as well as In response to receiving the secondary cell activation command and the TRS configuration, the secondary cell activation process is initiated based on the timing between the timing of the secondary cell activation command and the timing of the first fully available TRS.

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