Reference signal transmission in enhanced carrier aggregation

Abstract

Methods, systems, and devices for wireless communication are described. A user equipment (UE) may receive a first message including information indicating an inter-band carrier aggregation configuration identifying a set of cells for communication by the network node. The UE may receive a synchronization signal on a first cell of the set of cells via a wireless channel having a first set of channel attributes. Based on a first set of quasi-co-location (QCL) parameters including the first set of channel attributes, the UE may then receive one or more reference signals on the second cell of the set of cells. The UE may receive the one or more reference signals on the second cell based on the synchronization signal of the first cell, the synchronization signal of the first cell being a first QCL source indicative of receiving the one or more reference signals using the first set of QCL parameters.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This patent application claims the benefit of U.S. patent application No. 17 / 827,420, entitled “ENHANCING REFERENCE SIGNAL TRANSMISSION IN CARRIER AGGREGATION,” filed by Ly et al. on May 27, 2022, which is assigned to the assignee of this application. Background Art

[0003] The following relates to wireless communications, including enhancements to reference signal transmission in carrier aggregation (CA).

[0004] Wireless communication systems are widely deployed to provide various types of communication content, such as voice, video, packet data, messaging, broadcasting, etc. These systems may be able to support communication with multiple users by sharing available system resources (e.g., time, frequency, and power). Examples of such multiple access systems include fourth generation (4G) systems (such as long term evolution (LTE) systems, advanced LTE (LTE-A) systems, or LTE-A Pro systems) and fifth generation (5G) systems (which may be referred to as new radio (NR) systems). These systems may employ techniques such as code division multiple access (CDMA), time division multiple access (TDMA), frequency division multiple access (FDMA), orthogonal FDMA (OFDMA), or discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-S-OFDM). A wireless multiple access communication system may include one or more base stations, each of which supports wireless communication of communication devices, which may be referred to as user equipment (UE). Summary of the invention

[0005] The described technology relates to improved methods, systems, devices and apparatuses that support reference signal transmission in enhanced carrier aggregation (CA). For example, the described technology supports high-throughput communications and increased signaling based on increased system traffic, etc. However, from the perspective of the network, this relative increase in signaling may be costly in terms of power consumption. In order to address the problem of increased power consumption, some wireless communication systems may implement signaling reduction techniques, such as using downlink carriers that do not include synchronization signaling. However, synchronization signaling can be used to set a quasi-co-location (QCL) relationship (or can be used as a QCL source) for a receiving network node such as a user equipment (UE) to receive signaling on a cell where the receiving network node receives the synchronization signaling. Therefore, the network node can implement different techniques to identify a QCL source for communication on a non-SSB carrier.

[0006] In some aspects, the network node may receive a synchronization signal on a first cell (e.g., a primary cell) in a set of cells in an inter-band CA deployment, and may use the synchronization signal to determine QCL information for receiving communications on the first cell. In the case where the second cell (e.g., a secondary cell) is SSB-free, the network node may also use the synchronization signal received on the first cell as a QCL source for receiving reference signaling on the second cell. For example, the network node may receive the synchronization signal on the first cell via a wireless channel having a first set of channel attributes, and may then receive one or more reference signals on the second cell based on the first set of QCL parameters. In this case, the first set of channel attributes may be used to receive reference signaling on the second cell based on the synchronization signal as a QCL source.

[0007] A method for wireless communication at a network node is described. The method may include: receiving a first message including information indicating an inter-band CA configuration, the inter-band CA configuration identifying a set of cells for communication by the network node; receiving a synchronization signal on a first cell in the set of cells via a wireless channel having a first set of channel properties; and receiving one or more reference signals on a second cell in the set of cells based on a first set of QCL parameters including the first set of channel properties, the first set of QCL parameters being used based on the synchronization signal of the first cell, the synchronization signal of the first cell being a first QCL source indicating the use of the first set of QCL parameters to receive the one or more reference signals.

[0008] A network node for wireless communication is described. The apparatus may include: a memory; and at least one processor coupled to the memory. The at least one processor may be configured to: receive a first message including information indicating an inter-band carrier aggregation configuration, the inter-band carrier aggregation configuration identifying a set of cells for communication by the network node; receive a synchronization signal on a first cell in the set of cells via a wireless channel having a first set of channel attributes; and receive one or more reference signals on a second cell in the set of cells based on a first set of quasi-co-location (QCL) parameters including the first set of channel attributes, the first set of QCL parameters being used based on the synchronization signal of the first cell, the synchronization signal of the first cell being a first QCL source indicating the use of the first set of QCL parameters to receive the one or more reference signals.

[0009] Another network node for wireless communication is described. The network node may include: a component for receiving a first message, the first message including information indicating an inter-band carrier aggregation configuration, the inter-band carrier aggregation configuration identifying a set of cells for communication by the network node; a component for receiving a synchronization signal on a first cell in the set of cells via a wireless channel having a first set of channel attributes; and a component for receiving one or more reference signals on a second cell in the set of cells based on a first set of quasi-co-location (QCL) parameters including the first set of channel attributes, the first set of QCL parameters being used based on the synchronization signal of the first cell, the synchronization signal of the first cell being a first QCL source indicating the use of the first set of QCL parameters to receive the one or more reference signals.

[0010] A non-transitory computer-readable medium having code stored thereon is described. The code, when executed by a network node, may cause the network node to: receive a first message including information indicating an inter-band carrier aggregation configuration, the inter-band carrier aggregation configuration identifying a set of cells for communication by the network node; receive a synchronization signal on a first cell in the set of cells via a wireless channel having a first set of channel attributes; and receive one or more reference signals on a second cell in the set of cells based on a first set of quasi-co-location (QCL) parameters including the first set of channel attributes, the first set of QCL parameters being used based on the synchronization signal of the first cell, the synchronization signal of the first cell being a first QCL source indicating the use of the first set of QCL parameters to receive the one or more reference signals.

[0011] Some examples of the methods, network nodes, and non-transitory computer-readable media described herein may further include operations, features, components, or instructions for the following actions: receiving a first reference signal among the one or more reference signals on the second cell in the set of cells, wherein the synchronization signal of the first cell may be the first QCL source indicating the use of the first set of QCL parameters to receive the first reference signal; and receiving a second reference signal on the second cell in the set of cells in addition to the one or more reference signals, wherein the first reference signal of the second cell may be the second QCL source indicating the use of the second set of QCL parameters to receive the second reference signal.

[0012] Some examples of the methods, network nodes, and non-transitory computer-readable media described herein may further include operations, features, components, or instructions for the following actions: receiving the first reference signal and the second reference signal of the one or more reference signals based on the time and frequency synchronization information indicated by the synchronization signal of the first cell.

[0013] In some examples of the methods, network nodes, and non-transitory computer-readable media described herein, the first set of QCL parameters, the second set of QCL parameters, or both can be associated with one or more Doppler shift parameters, one or more Doppler spread parameters, one or more average delay parameters, one or more delay spread parameters, one or more spatial receiver parameters, or any combination thereof.

[0014] Some examples of the methods, network nodes, and non-transitory computer-readable media described herein may further include operations, features, components, or instructions for: receiving a first reference signal among the one or more reference signals on the first cell in the set of cells, wherein the synchronization signal of the first cell may be the first QCL source indicating the use of the first set of QCL parameters to receive the first reference signal; and receiving a second reference signal on the second cell in the set of cells in addition to the one or more reference signals, wherein the first reference signal of the first cell may be the second QCL source indicating the use of the second set of QCL parameters to receive the second reference signal.

[0015] Some examples of the methods, network nodes, and non-transitory computer-readable media described herein may further include operations, features, components, or instructions for receiving a first reference signal among the one or more reference signals on the second cell in the set of cells, wherein the synchronization signal of the first cell may be indicative of the first QCL source using the first set of QCL parameters to receive the first reference signal.

[0016] Some examples of the methods, network nodes, and non-transitory computer-readable media described herein may further include operations, features, components, or instructions for the following actions: receiving a first reference signal among the one or more reference signals on a third cell in the set of cells, wherein the synchronization signal of the first cell may be the first QCL source indicating the use of the first set of QCL parameters to receive the first reference signal; and receiving one or more communications on the second cell in the set of cells, wherein the first reference signal of the third cell may be a second QCL source indicating the use of the second set of QCL parameters to receive the one or more communications.

[0017] Some examples of the methods, network nodes, and non-transitory computer-readable media described herein may further include operations, features, components, or instructions for: receiving a second synchronization signal and a first reference signal among the one or more reference signals on a third cell in the set of cells, wherein the second synchronization signal of the third cell may be the first QCL source indicating the first set of QCL parameters for receiving the first reference signal; and receiving one or more communications on the second cell in the set of cells, wherein the second synchronization signal may be the first QCL source indicating the first set of QCL parameters for receiving the one or more communications, or wherein the first reference signal may be the second QCL source indicating the second set of QCL parameters for receiving the one or more communications.

[0018] Some examples of the methods, network nodes, and non-transitory computer-readable media described herein may further include operations, features, components, or instructions for the following actions: receiving the one or more communications on the second cell based on the time and frequency synchronization information indicated by the first synchronization signal of the first cell; and receiving the first reference signal on the third cell based on the additional time and frequency synchronization information indicated by the second synchronization signal of the second cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 and Figure 2 An example of a wireless communication system supporting enhanced reference signal transmission in carrier aggregation (CA) according to one or more aspects of the present disclosure is illustrated.

[0020] Figure 3 An example cell activation configuration supporting reference signal transmission in enhanced CA according to one or more aspects of the present disclosure is illustrated.

[0021] Figures 4 to 6 An example cell configuration supporting reference signal transmission in enhanced CA according to one or more aspects of the present disclosure is illustrated.

[0022] Figure 7 An example of a process flow to support reference signal transmission in enhanced CA according to one or more aspects of the present disclosure is illustrated.

[0023] Figure 8 and Fig. 9 A block diagram of an apparatus supporting reference signal transmission in enhanced CA according to one or more aspects of the present disclosure is shown.

[0024] Fig.10 A block diagram of a communication manager supporting reference signal transmission in enhanced CA is shown in accordance with one or more aspects of the present disclosure.

[0025] Fig.11 A diagram of a system including a device supporting reference signal transmission in enhanced CA according to one or more aspects of the present disclosure is shown.

[0026] Figures 12 to 16 A flow chart illustrating a method of supporting reference signal transmission in enhanced CA according to one or more aspects of the present disclosure is shown. DETAILED DESCRIPTION

[0027] Some wireless communication systems may have relatively high operating costs due to increased power consumption for high frequency and extended bandwidth operation, high throughput and low latency communications within the network, and a relative increase in signaling as wireless communication becomes more widely available. While this relative increase in signaling and throughput improves the overall user experience and system efficiency, it may also be costly in terms of power consumption from the network's perspective (e.g., the network and network devices may consume excessive amounts of power due to the increased signaling).

[0028] To address the problem of increased power consumption, some wireless communication systems may implement techniques to reduce excessive signaling between network devices and user equipment (UE). For example, one such technique for inter-band and intra-band carrier aggregation (CA) deployment may include the transmission of a downlink carrier that does not include a synchronization signal block (SSB) or is "SSB-free". For example, a network device may save power and reduce resource usage by prohibiting the transmission of SSBs on at least some of the downlink carriers transmitted to the network node. However, synchronization signaling may be used to set a quasi-co-location (QCL) relationship for a network node (or may be used as a QCL source) to receive reference signaling on a cell where the network node receives synchronization signaling, and may also indicate time and frequency tracking resources for the network node to communicate effectively on the cell. Therefore, a network node may implement different techniques to identify a QCL source (e.g., reference signaling, such as a tracking reference signal (TRS), such as a periodic TRS (P-TRS) and an aperiodic TRS (A-TRS)) for receiving communications on a carrier without SSB. A QCL source is a signal where the properties of the wireless channel over which the signal is received can be applied to receiving a different signal(s) on a different channel.

[0029] In some specific implementations, the network node may identify and set a QCL source for receiving signaling on a cell in which it does not receive an associated SSB. In some aspects, the network node may receive an SSB on a first cell (e.g., a primary cell) and may use the SSB to determine QCL information for receiving communications (e.g., reference signaling, such as periodic TRS and aperiodic TRS, such as periodic CSI-RS and aperiodic CSI-RS) on the first cell. In the case where a second cell (e.g., a secondary cell) is SSB-free, the network node may also use the SSB as a QCL source for receiving reference signaling on the second cell. For example, the network node may receive an SSB on a first cell and may use the SSB as a QCL source for receiving a P-TRS on a second cell, and the P-TRS may be a QCL source for receiving additional reference signaling such as an A-TRS on the second cell.

[0030] In some other examples, the network node may receive both the SSB and the first reference signal (e.g., P-TRS) on the first cell, and may use the QCL source of the first reference signal as the QCL source for receiving the second reference signal (e.g., A-TRS) on the second cell. In a third example, the network node may use the SSB received on the first cell as the QCL source for receiving the second reference signal (e.g., A-TRS) received on the second cell.

[0031] In some other examples, the network node may communicate on a first cell (e.g., a primary cell (PCell)), a second cell (e.g., a secondary cell (SCell) 2), and a third cell (e.g., SCell 2). The network node may receive SSB on the first cell and may receive TRS on the third cell but not on the second cell. In such examples, for example, in the case where the network node does not receive SSB or TRS on the second cell, the TRS may be a shared reference signal for the second cell and the third cell. The network node may also derive time and frequency tracking information for the second cell based on the shared reference signal.

[0032] First, various aspects of the present disclosure are described in the context of a wireless communication system. Various aspects of the present disclosure are further illustrated and described with reference to apparatus diagrams, system diagrams, cell configurations, process flows, and flowcharts related to reference signal transmission in enhanced CA.

[0033] Figure 1An example of a wireless communication system 100 supporting reference signal transmission in enhanced CA according to one or more aspects of the present disclosure is illustrated. The wireless communication system 100 may include one or more network entities 105, one or more UEs 115, and a core network 130, each of which may be an example of a network node described herein. In some aspects, the wireless communication system 100 may be a long term evolution (LTE) network, an advanced LTE (LTE-A) network, an LTE-A Pro network, a new radio (NR) network, or a network operating according to other systems and radio technologies (including future systems and radio technologies not explicitly mentioned herein).

[0034] The network entities 105 may be dispersed throughout a geographic area to form the wireless communication system 100, and may include devices in different forms or with different capabilities. In various examples, the network entities 105 may be referred to as network elements, mobility elements, radio access network (RAN) nodes, second network nodes, or network equipment, etc. In some aspects, the network entities 105 and the UE 115 may communicate wirelessly via one or more communication links 125 (e.g., radio frequency (RF) access links). For example, the network entity 105 may support a coverage area 110 (e.g., a geographic coverage area) within which the UE 115 and the network entity 105 may establish one or more communication links 125. The coverage area 110 may be an example of a geographic area within which the network entity 105 and the UE 115 may support signal communications according to one or more radio access technologies (RATs).

[0035] The UEs 115 may be dispersed throughout the coverage area 110 of the wireless communication system 100, and each UE 115 may be stationary or mobile, or stationary and mobile at different times. The UEs 115 may be devices in different forms or with different capabilities. Figure 1 Some example UEs 115 are illustrated in FIG. 1 . The UEs 115 described herein may be capable of communicating with various types of devices, such as Figure 1 Other UEs 115 or network entities 105 are shown.

[0036] As described herein, a node (which may be referred to as a node, a network node, a network entity, or a wireless node) may include, may be, or may be included in (e.g., as a component of) a base station (e.g., any base station described herein), a UE or a network node (e.g., any UE described herein), a network controller, an apparatus, a device, a computing system, an integrated access and backhaul (IAB) node, a distributed unit (DU), a central unit (CU), a remote / radio unit (RU) (which may also be referred to as a remote radio unit (RRU)), and / or another processing entity configured to perform any of the techniques described herein. For example, the network node may be a UE. For another example, the network node may be a base station or a network entity. As another example, a first network node may be configured to communicate with a second network node or a third network node. In one aspect of this example, the first network node may be a UE, the second network node may be a base station, and the third network node may be a UE.

[0037] In another aspect of this example, the first network node may be a UE, the second network node may be a base station, and the third network node may be a base station. In yet other aspects of this example, the first network node, the second network node, and the third network node may be different relative to these examples. Similarly, references to UE, base station, apparatus, device, computing system, etc. may include disclosure of UE, base station, apparatus, device, computing system, etc. as network nodes. For example, a disclosure that the UE is configured to receive information from a base station also discloses that the first network node is configured to receive information from a second network node.

[0038] Consistent with the present disclosure, once a specific example is expanded according to the present disclosure (e.g., a UE is configured to receive information from a base station and it is also disclosed that a first network node is configured to receive information from a second network node), a broader example of a narrower example can be interpreted inversely, but in a broad, open-ended manner. In the above example where a UE is configured to receive information from a base station and it is also disclosed that a first network node is configured to receive information from a second network node, the first network node may refer to a first UE configured to receive information, a first base station, a first device, a first equipment, a first computing system, a first group of one or more components, a first processing entity, etc.; and the second network node may refer to a second UE, a second base station, a second device, a second equipment, a second computing system, a second group of one or more components, a second processing entity, etc.

[0039] As described herein, different terms may be used in various aspects to describe the communication of information (e.g., any information, signal, etc.). The disclosure of one communication term includes the disclosure of other communication terms. For example, a first network node may be described as being configured to send information to a second network node. In this example and consistent with the present disclosure, the disclosure that the first network node is configured to send information to the second network node includes the disclosure that the first network node is configured to provide, send, output, transmit, or send information to the second network node. Similarly, in this example and consistent with the present disclosure, the disclosure that the first network node is configured to send information to the second network node includes the disclosure that the second network node is configured to receive, obtain, or decode information provided, sent, output, transmitted, or sent by the first network node.

[0040] In some aspects, the network entities 105 may communicate with the core network 130 or with each other, or both. For example, the network entities 105 may communicate with the core network 130 via one or more backhaul communication links 120 (e.g., according to S1, N2, N3, or other interface protocols). In some aspects, the network entities 105 may communicate with each other on the backhaul communication links 120 (e.g., according to X2, Xn, or other interface protocols) directly (e.g., directly between the network entities 105) or indirectly (e.g., via the core network 130). In some aspects, the network entities 105 may communicate with each other via the midhaul communication links 162 (e.g., according to the midhaul interface protocol) or the fronthaul communication links 168 (e.g., according to the fronthaul interface protocol) or any combination thereof. The backhaul communication links 120, the midhaul communication links 162, or the fronthaul communication links 168 may be or include one or more wired links (e.g., electrical links, optical fiber links), one or more wireless links (e.g., radio links, wireless optical links), etc. or various combinations thereof. UE 115 may communicate with core network 130 via communication link 155 .

[0041] One or more of the network entities 105 described herein may include or may be referred to as a base station 140 (e.g., a transceiver base station, a radio base station, an NR base station, an access point, a radio transceiver, a Node B, an evolved Node B (eNB), a next generation Node B, or a Gigabit Node B (any of which may be referred to as a gNB), a 5G NB, a next generation eNB (ng-eNB), a Home Node B, a Home Evolved Node B, or other suitable terminology). In some aspects, the network entity 105 (e.g., a base station 140) may be implemented in an aggregated (e.g., monolithic, stand-alone) base station architecture that may be configured to utilize a protocol stack that is physically or logically integrated within a single network entity 105 (e.g., a single RAN node, such as a base station 140).

[0042] In some aspects, the network entity 105 can be implemented in a disaggregated architecture (e.g., a disaggregated base station architecture, a disaggregated RAN architecture) that can be configured to utilize a protocol stack that is physically or logically distributed between two or more network entities 105, such as an integrated access backhaul (IAB) network, an open RAN (O-RAN) (e.g., a network configuration sponsored by the O-RAN Alliance), or a virtualized RAN (vRAN) (e.g., a cloud RAN (C-RAN)). For example, the network entity 105 can include one or more of the following: a central unit (CU) 160, a distributed unit (DU) 165, a radio unit (RU) 170, a RAN intelligent controller (RIC) 175 (e.g., a near real-time RIC (near RT RIC), a non-real-time RIC (non-RT RIC)), a service management and orchestration (SMO) 180 system, or any combination thereof. The RU 170 may also be referred to as a radio head, a smart radio head, a remote radio head (RRH), a remote radio unit (RRU), or a transmit receive point (TRP). One or more components of the network entity 105 in the decomposed RAN architecture may be co-located, or one or more components of the network entity 105 may be located in distributed locations (e.g., separate physical locations). In some aspects, one or more network entities 105 of the decomposed RAN architecture may be implemented as virtual units (e.g., virtual CU (VCU), virtual DU (VDU), virtual RU (VRU)).

[0043] The functional split between CU 160, DU 165, and RU 170 is flexible and can support different functionalities, depending on which functions (e.g., network layer functions, protocol layer functions, baseband functions, RF functions, and any combination thereof) are performed at CU 160, DU 165, or RU 170. For example, a functional split of a protocol stack can be employed between CU 160 and DU 165 such that CU 160 can support one or more layers of a protocol stack and DU 165 can support one or more different layers of a protocol stack. In some aspects, CU 160 can host higher protocol layer (e.g., layer 3 (L3), layer 2 (L2)) functionality and signaling (e.g., radio resource control (RRC), service data adaptation protocol (SDAP), packet data convergence protocol (PDCP)). The CU 160 may be connected to one or more DUs 165 or RUs 170, and the one or more DUs 165 or RUs 170 may host lower protocol layers, such as layer 1 (L1) (e.g., physical (PHY) layer) or L2 (e.g., radio link control (RLC) layer, medium access control (MAC) layer) functionality and signaling, and may each be at least partially controlled by the CU 160. Additionally or alternatively, a functional split of the protocol stack may be employed between the DU 165 and the RU 170, such that the DU 165 may support one or more layers of the protocol stack, and the RU 170 may support one or more different layers of the protocol stack. The DU 165 may support one or more different cells (e.g., via one or more RUs 170). In some cases, the functional split between CU 160 and DU 165 or between DU 165 and RU 170 can be within the protocol layer (e.g., some functions of the protocol layer can be performed by one of CU 160, DU 165, or RU 170, while other functions of the protocol layer are performed by different ones of CU 160, DU 165, or RU 170). CU 160 can be further functionally split into CU control plane (CU-CP) and CU user plane (CU-UP) functions. CU 160 can be connected to one or more DUs 165 via midhaul communication links 162 (e.g., F1, F1-c, F1-u), and DU 165 can be connected to one or more RUs 170 via fronthaul communication links 168 (e.g., open fronthaul (FH) interface). In some aspects, the midhaul communication link 162 or the fronthaul communication link 168 may be implemented based on interfaces (eg, channels) between layers of a protocol stack supported by respective network entities 105 communicating over those communication links.

[0044] In some wireless communication systems (e.g., wireless communication system 100), the infrastructure and spectrum resources for radio access can support wireless backhaul link capabilities to supplement the wired backhaul connection, thereby providing an IAB network architecture (e.g., to the core network 130). In some cases, in the IAB network, one or more network entities 105 (e.g., IAB nodes 104) can be partially controlled by each other. One or more IAB nodes 104 can be referred to as donor entities or IAB donors. One or more DUs 165 or one or more RUs 170 can be controlled in part by one or more CUs 160 associated with the donor network entity 105 (e.g., donor base station 140). One or more donor network entities 105 (e.g., IAB donors) can communicate with one or more additional network entities 105 (e.g., IAB nodes 104) via supported access and backhaul links (e.g., backhaul communication links 120). The IAB node 104 may include an IAB mobile terminal (IAB-MT) controlled (e.g., scheduled) by a coupled IAB donor's DU 165. The IAB-MT may include an independent set of antennas for relaying communications with the UE 115, or may share the same antennas of the IAB node 104 (e.g., of the RU 170) for access via the DU 165 of the IAB node 104 (e.g., referred to as a virtual IAB-MT (vIAB-MT)). In some aspects, the IAB node 104 may include a DU 165 that supports communication links with additional entities (e.g., IAB node 104, UE 115) within a relay chain or configuration (e.g., downstream) of the access network. In such cases, one or more components of the decomposed RAN architecture (e.g., one or more IAB nodes 104 or components of the IAB node 104) may be configured to operate according to the techniques described herein.

[0045] For example, an access network (AN) or RAN may include an access node (e.g., an IAB donor), communications between an IAB node 104, and one or more UEs 115. The IAB donor may facilitate connectivity between the core network 130 and the AN (e.g., via a wired or wireless connection to the core network 130). That is, the IAB donor may refer to a RAN node having a wired or wireless connection to the core network 130. The IAB donor may include a CU 160 and at least one DU 165 (e.g., and RU 170), in which case the CU 160 may communicate with the core network 130 via an interface (e.g., a backhaul link). The IAB donor and the IAB node 104 may communicate via an F1 interface according to a protocol defining a signaling message (e.g., an F1AP protocol). Additionally or alternatively, CU 160 may communicate with the core network via an interface (which may be an example of a portion of a backhaul link) and may communicate with other CUs 160 (e.g., CU 160 associated with an alternative IAB donor) via an Xn-C interface (which may be an example of a portion of a backhaul link).

[0046] An IAB node 104 may refer to a RAN node that provides IAB functionality (e.g., access for UE 115, wireless self-backhaul capabilities, etc.). DU 165 may act as a distributed scheduling node toward child nodes associated with IAB node 104, and IAB-MT may act as a scheduled node toward a parent node associated with IAB node 104. That is, an IAB donor may be referred to as a parent node that communicates with one or more child nodes (e.g., an IAB donor may relay transmissions to a UE through one or more other IAB nodes 104). Additionally or alternatively, depending on the relay chain or configuration of the AN, an IAB node 104 may also be referred to as a parent node or child node of other IAB nodes 104. Thus, the IAB-MT entity of the IAB node 104 may provide a Uu interface for the child IAB node 104 to receive signaling from the parent IAB node 104 , and the DU interface (eg, DU 165 ) may provide a Uu interface for the parent IAB node 104 to signal to the child IAB node 104 or the UE 115 .

[0047] For example, the IAB node 104 may be referred to as a parent node that supports communication of a child IAB node, and may be referred to as a child IAB node associated with an IAB donor. The IAB donor may include a CU 160 having a wired or wireless connection (e.g., a backhaul communication link 120) to the core network 130, and may act as a parent node of the IAB node 104. For example, the DU 165 of the IAB donor may relay the transmission to the UE 115 through the IAB node 104, and may directly signal the UE 115 of the transmission. The CU 160 of the IAB donor may signal the IAB node 104 of the communication link establishment via the F1 interface, and the IAB node 104 may schedule the transmission (e.g., the transmission relayed from the IAB donor to the UE 115) through the DU 165. That is, data may be relayed to and from the IAB node 104 via signaling through the NR Uu interface of the MT to the IAB node 104. Communications with the IAB node 104 may be scheduled by the DU 165 of the IAB donor, and communications with the IAB node 104 may be scheduled by the DU 165 of the IAB node 104 .

[0048] In the case where the techniques described herein are applied to the context of a decomposed RAN architecture, one or more components of the decomposed RAN architecture may be configured to support reference signal transmission in enhanced CA as described herein. For example, some operations described as being performed by a UE 115 or a network entity 105 (e.g., a base station 140) may additionally or alternatively be performed by one or more components of the decomposed RAN architecture (e.g., an IAB node 104, a DU 165, a CU 160, a RU 170, a RIC 175, a SMO 180).

[0049] UE 115 may include or may be referred to as a mobile device, a wireless device, a remote device, a handheld device, or a subscriber device, or some other suitable term, where a "device" may also be referred to as a unit, a station, a terminal, or a client, etc. UE 115 may also include or may be referred to as a personal electronic device, such as a cellular phone, a personal digital assistant (PDA), a tablet computer, a laptop computer, or a personal computer. In some aspects, UE 115 may include or be referred to as a wireless local loop (WLL) station, an Internet of Things (IoT) device, an Internet of Everything (IoE) device, or a machine type communication (MTC) device, etc., which may be implemented in various objects such as electrical appliances or vehicles, meters, etc.

[0050] The UE 115 described herein may be capable of communicating with various types of devices, such as other UEs 115, which may sometimes act as relays, as well as network entities 105 and network equipment including macro eNBs or gNBs, small cell eNBs or gNBs, relay base stations, etc. Figure 1 shown.

[0051] UE 115 and network entity 105 can communicate with each other wirelessly via one or more communication links 125 (e.g., access links) through one or more carriers. The term "carrier" may refer to a set of RF spectrum resources having a physical layer structure defined to support communication link 125. For example, a carrier for communication link 125 may include a portion of an RF spectrum band (e.g., bandwidth portion (BWP)) that operates according to one or more physical layer channels for a given radio access technology (e.g., LTE, LTE-A, LTE-APro, NR). Each physical layer channel may carry acquisition signaling (e.g., synchronization signals, system information), control signaling for coordinating carrier operations, user data, or other signaling. The wireless communication system 100 may support communication with UE 115 using CA or multi-carrier operation. UE 115 may be configured to have multiple downlink component carriers and one or more uplink component carriers according to the CA configuration. Carrier aggregation may be used for both frequency division duplex (FDD) and time division duplex (TDD) component carriers. Communication between the network entity 105 and other devices may refer to communication between these devices and any portion (e.g., entity, sub-entity) of the network entity 105. For example, the terms "send," "receive," or "communicate" when referring to the network entity 105 may refer to any portion of a network entity 105 (e.g., base station 140, CU 160, DU 165, RU 170) of a RAN communicating with another device (e.g., directly or via one or more other network entities 105).

[0052] In some aspects, such as in a CA configuration, a carrier may also have acquisition signaling or control signaling that coordinates the operation of other carriers. A carrier may be associated with a frequency channel (e.g., an Evolved Universal Mobile Telecommunications System Terrestrial Radio Access (E-UTRA) Absolute RF Channel Number (EARFCN)) and may be located based on a channel raster for discovery by UE 115. A carrier may operate in a standalone mode, in which case initial acquisition and connection may be made by UE 115 via the carrier, or a carrier may operate in a non-standalone mode, in which case a different carrier (e.g., of the same or different radio access technology) is used to anchor the connection.

[0053] The communication link 125 shown in the wireless communication system 100 may include downlink transmissions (e.g., forward link transmissions) from the network entity 105 to the UE 115, uplink transmissions (e.g., return link transmissions) from the UE 115 to the network entity 105, or both, as well as other transmission configurations. A carrier may carry either downlink communications or uplink communications (e.g., in FDD mode), or may be configured to carry both downlink communications and uplink communications (e.g., in TDD mode).

[0054] A carrier may be associated with a particular bandwidth of the RF spectrum, and in some examples, the carrier bandwidth may be referred to as the "system bandwidth" of the carrier or wireless communication system 100. For example, the carrier bandwidth may be one of a set of bandwidths of carriers of a particular radio access technology (e.g., 1.4 megahertz (MHz), 3 MHz, 5 MHz, 10 MHz, 15 MHz, 20 MHz, 40 MHz, or 80 MHz). A device of the wireless communication system 100 (e.g., a network entity 105, a UE 115, or both) may have a hardware configuration that supports communication over a particular carrier bandwidth, or may be configured to support communication over one of the carrier bandwidths in the set of carrier bandwidths. In some aspects, the wireless communication system 100 may include a network entity 105 or a UE 115 that supports concurrent communication via carriers associated with multiple carrier bandwidths. In some aspects, each served UE 115 may be configured to operate on a portion (e.g., a subband, a BWP) or all of the carrier bandwidth.

[0055] The signal waveform transmitted through the carrier may be composed of multiple subcarriers (e.g., using multi-carrier modulation (MCM) techniques, such as orthogonal frequency division multiplexing (OFDM) or discrete Fourier transform spread OFDM (DFT-S-OFDM)). In a system employing MCM techniques, a resource element may refer to a symbol period (e.g., the duration of a modulation symbol) and a subcarrier resource, in which case the symbol period and the subcarrier spacing may be inversely related. The number of bits carried by each resource element may depend on the modulation scheme (e.g., the order of the modulation scheme, the coding rate of the modulation scheme, or both), such that the more resource elements a device receives and the higher the order of the modulation scheme, the higher the data rate of the device may be. Wireless communication resources may refer to a combination of RF spectrum resources, time resources, and spatial resources (e.g., spatial layers or beams), and the use of multiple spatial resources may increase the data rate or data integrity used for communication with UE 115.

[0056] One or more parameter sets for a carrier may be supported, where the parameter set may include a subcarrier spacing (Δf) and a cyclic prefix. A carrier may be divided into one or more BWPs with the same or different parameter sets. In some aspects, a UE 115 may be configured with multiple BWPs. In some aspects, a single BWP for a carrier may be active at a given time, and communications for a UE 115 may be limited to the one or more active BWPs.

[0057] The time interval for the network entity 105 or the UE 115 may be expressed in multiples of a basic time unit, which may be, for example, a sampling period T s =1 / (Δf max ·N f ) seconds, where Δf max It can represent the maximum supported subcarrier spacing, and N f The maximum supported discrete Fourier transform (DFT) size may be indicated. The time intervals of the communication resources may be organized according to radio frames each having a specified duration (e.g., 10 milliseconds (ms)). Each radio frame may be identified by a system frame number (SFN) (e.g., ranging from 0 to 1023).

[0058] Each frame may include multiple consecutively numbered subframes or time slots, and each subframe or time slot may have the same duration. In some aspects, a frame may be divided into subframes (e.g., in the time domain), and each subframe may be further divided into a certain number of time slots. Alternatively, each frame may include a variable number of time slots, and the number of time slots may depend on the subcarrier spacing. Each time slot may include a certain number of symbol periods (e.g., depending on the length of the cyclic prefix appended in front of each symbol period). In some wireless communication systems 100, the time slot may be further divided into multiple micro-time slots containing one or more symbols. Excluding the cyclic prefix, each symbol period may contain one or more (e.g., N f The duration of a symbol period may depend on the subcarrier spacing or the operating frequency band.

[0059] A subframe, a time slot, a mini-time slot, or a symbol may be the smallest scheduling unit (e.g., in the time domain) of the wireless communication system 100 and may be referred to as a transmission time interval (TTI). In some aspects, the TTI duration (e.g., the number of symbol periods in a TTI) may be variable. Additionally or alternatively, the smallest scheduling unit of the wireless communication system 100 may be dynamically selected (e.g., in a burst of a shortened TTI (sTTI)).

[0060] Physical channels may be multiplexed on a carrier according to various techniques. Physical control channels and physical data channels may be multiplexed on a downlink carrier using, for example, one or more of a time division multiplexing (TDM) technique, a frequency division multiplexing (FDM) technique, or a hybrid TDM-FDM technique. A control region (e.g., a control resource set (CORESET)) of a physical control channel may be defined by a set of symbol periods and may extend across a system bandwidth of a carrier or a subset of that system bandwidth. One or more control regions (e.g., CORESETs) may be configured for a set of UEs 115. For example, one or more UEs in UE 115 may monitor or search a control region to obtain control information according to one or more search space sets, and each search space set may include one or more control channel candidates in one or more aggregation levels arranged in a cascaded manner. The aggregation level of a control channel candidate may refer to the amount of control channel resources (e.g., control channel elements (CCEs)) associated with coded information for a control information format having a given payload size. The search space sets may include a common search space set configured for transmitting control information to multiple UEs 115 , and a UE-specific search space set for transmitting control information to a specific UE 115 .

[0061] The network entity 105 may provide communication coverage via one or more cells (e.g., macro cells, small cells, hotspots, or other types of cells, or any combination thereof). The term "cell" may refer to a logical communication entity used to communicate with the network entity 105 (e.g., via a carrier), and may be associated with an identifier (e.g., a physical cell identifier (PCID), a virtual cell identifier (VCID), or other cell identifier) ​​used to distinguish adjacent cells. In some aspects, a cell may also refer to a coverage area 110 or a portion of a coverage area 110 (e.g., a sector) on which a logical communication entity operates. Depending on various factors such as the capabilities of the network entity 105, such cells may range from smaller areas (e.g., structures, subsets of structures) to larger areas. For example, a cell may be or may include a building, a subset of a building, or an external space between or overlapping coverage areas 110, and the like.

[0062] A macro cell generally covers a relatively large geographic area (e.g., a radius of several kilometers) and may allow unrestricted access to a UE 115 with a service subscription and a network provider that supports the macro cell. A small cell may be associated with a lower power network entity 105 (e.g., a lower power base station 140) compared to a macro cell, and the small cell may operate in the same or different (e.g., licensed, unlicensed) frequency band as the macro cell. A small cell may provide unrestricted access to a UE 115 with a service subscription to a network provider, or may provide restricted access to a UE 115 associated with a small cell (e.g., a UE 115 in a closed subscriber group (CSG), a UE 115 associated with a user in a home or office). A network entity 105 may support one or more cells, and may also use one or more component carriers to support communications on one or more cells.

[0063] In some aspects, a carrier may support multiple cells, and different cells may be configured according to different protocol types (e.g., MTC, narrowband IoT (NB-IoT), enhanced mobile broadband (eMBB)) that may provide access to different types of devices.

[0064] In some aspects, the network entities 105 (e.g., base stations 140, RUs 170) may be mobile and thus provide communication coverage for mobile coverage areas 110. In some aspects, different coverage areas 110 associated with different technologies may overlap, but the different coverage areas 110 may be supported by the same network entity 105. In some other examples, overlapping coverage areas 110 associated with different technologies may be supported by different network entities 105. The wireless communication system 100 may include, for example, a heterogeneous network in which different types of network entities 105 provide coverage for various coverage areas 110 using the same or different radio access technologies.

[0065] The wireless communication system 100 may support synchronous operation or asynchronous operation. For synchronous operation, the network entities 105 (e.g., base stations 140) may have similar frame timing, and transmissions from different network entities 105 may be approximately aligned in time. For asynchronous operation, the network entities 105 may have different frame timing, and in some examples, transmissions from different network entities 105 may not be aligned in time. The techniques described herein may be used for either synchronous or asynchronous operation.

[0066] The wireless communication system 100 can be configured to support ultra-reliable communication or low-latency communication or various combinations thereof. For example, the wireless communication system 100 can be configured to support ultra-reliable low-latency communication (URLLC). UE 115 can be designed to support ultra-reliable or low-latency or critical functions. Ultra-reliable communication can include private communication or group communication, and can be supported by one or more services (such as push-to-talk, video or data). Support for ultra-reliable, low-latency functions can include prioritization of services, and such services can be used for public safety or general commercial applications. The terms ultra-reliable, low-latency and ultra-reliable low-latency can be used interchangeably in this article.

[0067] In some aspects, a UE 115 may be able to communicate directly with other UEs 115 over a device-to-device (D2D) communication link 135 (e.g., according to a peer-to-peer (P2P) protocol, a D2D protocol, or a sidelink protocol). In some aspects, one or more UEs 115 in a group that are performing D2D communication may be within a coverage area 110 of a network entity 105 (e.g., a base station 140, a RU 170), which may support various aspects of such D2D communication as configured or scheduled by the network entity 105. In some aspects, one or more UEs 115 in the group may be outside of the coverage area 110 of the network entity 105, or may otherwise be unable or not configured to receive transmissions from the network entity 105. In some aspects, a group of UEs 115 communicating via D2D communication may support a one-to-many (1:M) system, where each UE 115 transmits to each other UE 115 in the group. In some aspects, the network entity 105 may facilitate scheduling resources for D2D communication. In some other examples, D2D communications may be performed between UEs 115 without involving network entity 105 .

[0068] The core network 130 may provide user authentication, access authorization, tracking, Internet Protocol (IP) connectivity, and other access, routing, or mobility functions. The core network 130 may be an evolved packet core (EPC) or a 5G core (5GC), which may include at least one control plane entity (e.g., a mobility management entity (MME), an access and mobility management function (AMF)) for managing access and mobility and at least one user plane entity (e.g., a serving gateway (S-GW), a packet data network (PDN) gateway (P-GW), or a user plane function (UPF)) for routing packets or interconnecting to an external network. The control plane entity may manage non-access stratum (NAS) functions, such as mobility, authentication, and bearer management of UE 115 served by a network entity 105 (e.g., a base station 140) associated with the core network 130. User IP packets may be delivered through the user plane entity, which may provide IP address allocation and other functions. The user plane entity may be connected to the IP service 150 of one or more network operators. IP services 150 may include access to the Internet, an intranet, an IP Multimedia Subsystem (IMS), or packet-switched streaming services.

[0069] The wireless communication system 100 can operate using one or more frequency bands that can be in the range of 300 megahertz (MHz) to 300 gigahertz (GHz). Generally speaking, the area from 300MHz to 3GHz is called the ultra-high frequency (UHF) area or decimeter band because the wavelength ranges from about one decimeter to one meter in length. UHF waves may be blocked or redirected by buildings and environmental features (which may be referred to as clusters), but these waves may be sufficient to penetrate the structure so that the macrocell provides service to the UE 115 located indoors. Compared with the transmission of smaller frequencies and longer wavelengths using the high frequency (HF) or very high frequency (VHF) portion of the spectrum below 300MHz, the transmission of UHF waves may be associated with smaller antennas and shorter ranges (e.g., less than 100 kilometers).

[0070] The wireless communication system 100 can utilize both licensed RF spectrum bands and unlicensed RF spectrum bands. For example, the wireless communication system 100 can use license assisted access (LAA), LTE unlicensed (LTE-U) radio access technology, or NR technology in an unlicensed band (such as the 5 GHz industrial, scientific, and medical (ISM) band). When operating in an unlicensed RF spectrum band, devices such as network entities 105 and UE 115 can use carrier sensing for conflict detection and avoidance. In some aspects, operations in unlicensed bands can be based on a CA configuration (e.g., LAA) in conjunction with component carriers operating in a licensed band. Operations in an unlicensed spectrum may include downlink transmissions, uplink transmissions, P2P transmissions, or D2D transmissions, and the like.

[0071] The network entity 105 (e.g., base station 140, RU 170) or UE 115 may be equipped with multiple antennas that may be used to employ techniques such as transmit diversity, receive diversity, multiple-input multiple-output (MIMO) communications, or beamforming. The antennas of the network entity 105 or UE 115 may be located within one or more antenna arrays or antenna panels, which may support MIMO operations or transmit or receive beamforming. For example, one or more base station antennas or antenna arrays may be co-located at an antenna assembly, such as an antenna tower. In some aspects, antennas or antenna arrays associated with the network entity 105 may be located in different geographic locations. The network entity 105 may have an antenna array having a collection of multiple rows and columns of antenna ports that the network entity 105 may use to support beamforming for communications with the UE 115. Similarly, the UE 115 may have one or more antenna arrays that may support various MIMO or beamforming operations. Additionally or alternatively, the antenna panel may support RF beamforming for signals sent via the antenna ports.

[0072] The network entity 105 or UE 115 can use MIMO communication to utilize multipath signal propagation and improve spectral efficiency by sending or receiving multiple signals via different spatial layers. Such technology can be referred to as spatial multiplexing. The multiple signals can be sent, for example, by a transmitting device via different antennas or different combinations of antennas. Similarly, the multiple signals can be received by a receiving device via different antennas or different combinations of antennas. Each of the multiple signals can be referred to as a separate spatial stream and can carry information associated with the same data stream (e.g., the same codeword) or different data streams (e.g., different codewords). Different spatial layers can be associated with different antenna ports for channel measurement and reporting. MIMO technology includes single-user MIMO (SU-MIMO) and multi-user MIMO (MU-MIMO), in which multiple spatial layers are sent to the same receiving device and in which multiple spatial layers are sent to multiple devices.

[0073] Beamforming (which may also be referred to as spatial filtering, directional transmission, or directional reception) is a signal processing technique that may be used at a sender device or a receiver device (e.g., network entity 105, UE 115) to shape or direct an antenna beam (e.g., a transmit beam, a receive beam) along a spatial path between the sender device and the receiver device. Beamforming may be achieved by combining signals conveyed via antenna elements of an antenna array so that some signals propagating in a particular direction relative to the antenna array experience constructive interference, while other signals experience destructive interference. Adjustments to signals conveyed via antenna elements may include the sender device or the receiver device applying an amplitude offset, a phase offset, or both to signals carried via antenna elements associated with the device. Adjustments associated with each of these antenna elements may be defined by a set of beamforming weights associated with a particular direction (e.g., relative to the antenna array of the sender device or the receiver device or relative to some other direction).

[0074] The wireless communication system 100 can be a packet-based network that operates according to a layered protocol stack. In the user plane, the communication at the bearer or PDCP layer can be IP-based. The RLC layer can perform packet segmentation and reorganization to communicate through logical channels. The MAC layer can perform priority processing and multiplexing of logical channels into transport channels. The MAC layer can also use error detection technology, error correction technology, or both to support retransmission at the MAC layer to improve link efficiency. In the control plane, the RRC protocol layer can provide the establishment, configuration, and maintenance of the RRC connection that supports the radio bearer of user plane data between the UE 115 and the network entity 105 or the core network 130. At the PHY layer, the transport channel can be mapped to the physical channel.

[0075] Various components of the wireless communication system 100 may contribute to the overall energy consumption of the network. In some aspects, a relatively large portion of the energy consumption of the wireless communication system is attributed to radio access network (RAN) operations, e.g., power usage of network entities and other network devices. Although high power operations from the RAN can increase performance metrics such as data rate and throughput while reducing latency, techniques to increase energy saving features can also be implemented to support further expansion and efficiency of cellular networks.

[0076] In some aspects, a network entity such as a base station may consume energy according to one or more energy consumption models (e.g., for RAN1). In some aspects, the energy consumption model may indicate relative energy consumption of downlink and uplink communications (based on various factors such as power added (PA) efficiency, number of transceiver units, base station loading, etc.), sleep states and associated transition times, and one or more reference parameters / configurations.

[0077] In some aspects, network performance may be evaluated using an evaluation method and one or more key performance indicators (KPIs). The evaluation method may identify system-level network energy consumption and energy saving gains, and may evaluate the impact on network and user performance (e.g., spectrum efficiency, capacity, user perceived throughput (UPT), latency, handover performance, call drop rate, initial access performance, service level agreement (SLA) guarantee-related KPIs), energy efficiency, and UE power consumption and complexity. The evaluation method may evaluate more than one KPI, and existing KPIs may be reused. Additionally or alternatively, existing KPIs may be updated or new KPIs may be developed for additional evaluation.

[0078] In some aspects, the wireless communication system 100 may implement a variety of techniques (e.g., network-centric techniques, UE-centric techniques, or both) to increase network energy savings in terms of network transmission and reception. Some techniques may include dynamic or semi-static signaling and finer granularity communication adaptation to increase power savings. Some techniques may be applicable to the time domain, frequency domain, spatial domain, and power domain, and may implement feedback from the UE and UE assistance information to increase power savings.

[0079] In some aspects, various power saving techniques can be applied to networks with idle to empty network loads or low to medium network load scenarios, where there may be different loads between carriers and adjacent cells. The power saving techniques can be applied to both single-carrier deployments and multi-carrier deployments, to urban microcells in frequency range 1 (FR1), TDD massive MIMO, small cell models, FR2 beam-based scenarios, urban macrocells and suburban macrocells in FR1 (with or without dynamic spectrum sharing), EN-DC macrocells or NR-DC macrocells with FDD PCells, and TDD / massive MIMO on higher FR1 / FR2 frequencies. In some aspects, UE 115 can continue to access a network that implements network-centric energy saving techniques and UE-centric energy saving techniques.

[0080] In some aspects, the wireless communication system 100 may support SSB-free carriers to increase network-side energy savings. For example, an SSB in a first carrier may provide time and frequency synchronization information for a second carrier that does not have an associated SSB (e.g., the second carrier in this case is an SSB-free carrier). The network can save power by reducing the amount of signaling used to send SSBs, because the network can send SSBs on the selected carrier while prohibiting the sending of SSBs on other carriers. In some aspects, the network may support SSB-free carriers in FR1 segmented bands, where these bands are adjacent (e.g., 700MHz / 800MHz / 900MHz, 1.8GHz / 2.1GHz, 1.9GHz / 2GHz / 2.3GHz), but other bands are also possible. In some specific implementations, the wireless communication system may support SSB-free carriers for inter-band CA scenarios and intra-band C scenarios. Such SSB-free carriers can reduce cell activation delays (e.g., by facilitating efficient secondary cell (SCell) activation and deactivation based on network traffic), and can increase resource utilization by reducing overhead. In some aspects, inter-band CA with SSB-free carriers may further reduce broadcast overhead for known cells (e.g., Sub-6, 30kHz, 8 SSB, TDD with slot configuration 7D:1S:2U and S slots 10D:2F:2U).

[0081] Some wireless communication systems may have relatively high operating costs due to increased power consumption, high throughput scenarios, and a relative increase in signaling. However, from a network perspective (e.g., for radio access network (RAN) equipment and other network equipment), this relative increase in signaling may be costly in terms of power consumption. In order to address the problem of increased power consumption, some wireless communication systems may implement signaling reduction techniques, such as implementing the transmission of downlink carriers that do not include SBS. For example, the network device 105 can save power and reduce resource usage by prohibiting the transmission of SSB on at least some of the downlink carriers transmitted to the receiving first network node 115 (such as UE 115). However, synchronization signaling can be used to set a QCL relationship for the first network node 115 (or can be used as a QCL source) to receive reference signaling on the cell where the first network node receives synchronization signaling, and can also indicate time and frequency tracking resources for the first network node 115. Therefore, the first network node 115 can implement different techniques to identify the QCL source for communication on the SSB-free carrier.

[0082] In some aspects, the first network node 115 may receive an SSB on a first cell (e.g., a primary cell) and may use the SSB to determine QCL information for receiving communications on the first cell. In the case where the second cell (e.g., a secondary cell) is SSB-free, the first network node 115 may also use the SSB received on the first cell as a QCL source for receiving reference signaling on the second cell. For example, the first network node 115 may receive an SSB on the first cell and may use the SSB as a QCL source for receiving a P-TRS on the second cell, and the P-TRS may be a QCL source for receiving additional reference signaling such as an A-TRS on the second cell.

[0083] In some other examples, the first network node 115 may receive both the SSB and the first reference signal (e.g., P-TRS) on the first cell, and may use the QCL source of the first reference signal as the QCL source for receiving the second reference signal (e.g., A-TRS) on the second cell. In a third example, the first network node 115 may use the SSB received on the first cell as the QCL source for receiving the second reference signal (e.g., A-TRS) received on the second cell.

[0084] In some other examples, the first network node 115 may communicate on a first cell (e.g., PCell), a second cell, and a third cell (e.g., SCell 2). The first network node 115 may receive SSB on the first cell and may receive TRS on the third cell but not on the second cell. In such examples, for example, in the case where the network node does not receive SSB or TRS on the second cell, the TRS may be a shared reference signal for the second cell and the third cell. The network node may also derive time and frequency tracking information for the second cell based on the shared reference signal.

[0085] Figure 2 An example of a wireless communication system 200 that supports reference signal transmission in enhanced CA according to one or more aspects of the present disclosure is illustrated. For example, the wireless communication system 200 can illustrate communication between the first network node 115-a and the network entities 105-a, 105-b, and 105-c, which can be examples of corresponding devices described herein.

[0086] The wireless communication system 200 may support high frequency communications over an extended bandwidth to increase system throughput. The relative increase in signaling and throughput improves the overall user experience and system efficiency, but from a network perspective, this may also be costly in terms of power consumption (e.g., the network entity 105 may consume excessive power due to increased signaling). Some wireless communication systems may implement techniques to address the problem of excessive power consumption, including techniques to reduce excessive signaling between the second network node 105 and the first network node 115. For example, one such technique for inter-band and intra-band CA deployments may include transmission of downlink carriers that do not include SSBs. For example, the second network node 105 may save both power and resources by prohibiting the transmission of SSBs on at least some of the downlink carriers transmitted to the first network node 115-a. SSB-free carriers in inter-band CA deployments may also improve the efficiency of secondary cell (SCell) activation while reducing broadcast overhead to further increase energy savings. However, synchronization signaling (such as synchronization signaling associated with SSB) can be used to set a QCL relationship (or serve as a QCL source) for the first network node 115 to be able to receive reference signaling on the cell, and can indicate time and frequency tracking resources for the network node to effectively communicate on the cell. Therefore, in the event that the first network node 115 does not receive SSB on a carrier, the first network node 115 can implement different techniques to identify a QCL source for receiving communications (e.g., reference signaling such as TRS) on a carrier without SSB.

[0087] In some specific implementations, the first network node 115-a can identify and set a QCL source for receiving signaling on a cell where it does not receive an associated SSB. The first network node 115-a can communicate with the network entities 105-a, 105-b, and 105-c on the corresponding cells (e.g., carriers) 205-a, 205-b, and 205-c. In a first example, the first network node 115-a can receive an SSB 210 on a first cell 205-a (e.g., a primary cell) and can use the SSB to determine QCL information for receiving communications (e.g., reference signaling such as periodic TRS and aperiodic TRS) on the first cell 205-a. In the case where the second cell 205-b (e.g., a secondary cell) is SSB-free, the network node can also use the SSB 210 as a QCL source 215 for receiving reference signaling on the second cell 205-b. A QCL source is a signal in which properties of a radio channel on which a signal is received (e.g., receiving SSB 210 on cell 205-a) may be applied to receiving a different signal on a different channel (e.g., receiving reference signal 220 on cell 205-b). For example, a first network node 115-a may receive SSB 210 on a first cell 205-a and may use SSB 210 as a QCL source 215 for receiving P-TRS 230 on a second cell 205-b, and P-TRS may be a QCL source 215 for receiving additional reference signaling such as aperiodic CSI-RS or A-TRS 225 on the second cell 205-b.

[0088] In a second example, the network node may receive both the SSB 210 and the first reference signal 230 (e.g., P-TRS 230) on the first cell 205-a, and may use the QCL source 215 of the first reference signal 230 as the QCL source 215 for receiving the second reference signal 225 (e.g., A-TRS 225) on the second cell 205-b. In a third example, the first network node 115-a may use the SSB 210 received on the first cell 205-a as the QCL source 215 for receiving the second reference signal 225 (e.g., A-TRS 225) received on the second cell 205-b.

[0089] In some other examples, the network node may communicate on a first cell 205-a (e.g., PCell), a second cell 205-b (e.g., SCell 1), and a third cell (e.g., SCell 2) in an inter-band CA deployment. The first network node 115-a may receive the SSB 210 on the first cell 205-a and may receive the TRS 235 on the third cell 205-c. The network node may not receive the SSB on the third cell. In some aspects, the TRS 235 may be a shared reference signal for the second cell 205-b and the third cell 205-c, for example, when the first network node 115-a does not receive the SSB or TRS on the second cell 205-b. The first network node 115-a may derive time and frequency tracking information for the second cell 205-b based on the shared reference signal 235.

[0090] In some other examples, the network nodes may communicate on a first cell 205-a (e.g., PCell), a second cell 205-b (e.g., SCell 1), and a third cell (e.g., SCell 2) in an inter-band CA deployment. The first network node 115-a may receive the SSB 210 on the first cell 205-a and may receive the SSB and TRS 235 on the third cell 205-c. In some aspects, the TRS 235 may be a shared reference signal for the third cell 205-c and the second cell 205-b, for example, when the first network node 115-a does not receive the SSB or TRS on the second cell 205-b. The first network node 115-a may derive time and frequency tracking information for the second cell 205-b based on the TRS 235 and SSB received on the third cell 205-c.

[0091] Figure 3 Example cell activation configurations 300-a, 300-b, and 300-c supporting reference signal transmission in enhanced CA according to one or more aspects of the present disclosure are illustrated. In some aspects, the cell activation configurations 300-a, 300-b, and 300-c may be implemented at or by one or more devices described herein. For example, the cell activation configurations 300-a, 300-b, and 300-c may be implemented at or by a network node such as a UE or a network entity, or both.

[0092] The cell configuration 300-a shows a first SCell activation configuration including a first cell (e.g., PCell) and a second cell (e.g., SCell). The network node may periodically receive SSBs 305 on the SCell, which may include time and frequency synchronization information or other information for communicating on the SCell. In some aspects, the network node may receive an activation command 315 and a confirmation 320 for activating the SCell during an activation period (e.g., T_activation time). In some aspects, the network node may wait until the next periodic SSB opportunity (e.g., SSB 305-c) occurring after the activation command 315 to activate the SCell and perform synchronization measurements. However, in some other cases, the network node may activate the SCell and perform synchronization measurements using a TRS 310 occurring after the activation command 315 and before the next SSB opportunity 305-c, which may reduce latency. Similar to the SSB, the TRS 310 may be used for AGC measurements and time and frequency measurement tracking, and the activation of the SCell using the TRS may be applied to both intra-band CA deployments and inter-band CA deployments.

[0093] The cell configuration 300-b shows a second SCell activation configuration, which shows an example of triggering TRS via MAC-CE. For example, at 325-a, the network node can receive a PDSCH that includes a MAC-CE that triggers SCell activation and indicates TRS 310-b on the SCell. The network node can use a HARQ-ACK message 330-a to confirm that the MAC-CE is received on the PCell, and can activate the SCell based on the received MAC-CE. The network node can then use TRS 310-b to perform measurements on the activated SCell.

[0094] The cell configuration 300-c shows a second SCell activation configuration, which shows an example of triggering TRS via DCI. For example, at 325-b, the network node may receive a PDSCH that includes a MAC-CE that triggers SCell activation and indicates TRS 310-c on the SCell. The network node may use a HARQ-ACK message 330-b to confirm receipt of the MAC-CE on the PCell. The network node may then receive DCI 335 in a PDCCH that triggers TRS 310-c (e.g., A-TRS) on the secondary cell. The network node may then use TRS 310-c to perform measurements on the activated SCell.

[0095] In some aspects, the reference signal may be an A-TRS using a P-TRS in the SCell to be activated as a QCL source. For example, the network node may receive the P-TRS on the SCell using a first QCL relationship and may receive the A-TRS using the same QCL relationship. In some aspects, an SSB for a cell or carrier (e.g., an SSB for an SCell) may be used to set a QCL relationship (or used as a QCL source) for the network node so that reference signaling may be received on the cell. However, in some cases, a carrier may not have an SSB (e.g., a carrier may be SSB-free), and therefore the network node may implement a variety of different techniques to take into account channel estimation, frequency offset error estimation, and synchronization procedures on a cell without an SSB.

[0096] Figure 4 Example cell configurations 400-a, 400-b, 400-c, and 400-d supporting reference signal transmission in enhanced CA according to one or more aspects of the present disclosure are illustrated. In some aspects, the cell configurations 400-a, 400-b, 400-c, and 400-d may be implemented at or by one or more devices described herein. For example, the cell configurations 400-a, 400-b, 400-c, and 400-d may be implemented at or by a network node such as a UE or a network entity, or both.

[0097] In some aspects, the cell configuration may support inter-band CA for carriers without associated SSBs (e.g., SSB-free carriers). To support inter-band CA, the network may also specify a maximum receive timing difference (MRTD) target that is relatively smaller than a specific implementation for a carrier including SBS. A relatively high MRTD target may increase the relative frame timing alignment at the receiver and may correspond to the maximum relative receive timing difference that the network node may be able to handle. In some aspects, the MRTD target for inter-band CA may be within a threshold amount of the MRTD target for intra-band CA. In some aspects, MRTD may be affected by whether TRS is included on a SSB-free carrier (e.g., based on time and frequency tracking associated with TRS and AGC settings and in the case where there is a relatively large power difference between the serving cell and the SCell to be activated, the MRTD target may be increased). In some aspects, the network node may support relative MRTD between the slot timing of all carrier pairs to be aggregated at the network node receiver, and MRTD may be different for different carrier frequencies. For example, for inter-band aggregated carriers operating in FR1, the network node may support up to 33 μs of MRTD. For FR2, the network node may support up to 8 μs MRTD and for frequencies between FR1 and FR2, the network node may support up to 25 μs MRTD.For intra-band aggregated carriers operating in FR1, the network node may support up to 3 μs MRTD and for FR2, the network node may support up to 0.26 μs MRTD.

[0098] Additionally or alternatively, to support inter-band CA of carriers without associated SSB (e.g., SSB-free carriers), the SSB-free carriers may be co-located with carriers with associated SSBs so that the SSB-free carriers may provide time and frequency synchronization information for the SSB-free carriers. Such co-location may also support the transmission of TRSs, since the time and frequency information of the SSB-free carriers may be identified based on the SSB-free carriers.

[0099] The first cell configuration 400-a shows a PCell with SSB, where both the first SCell (e.g., SCell 1) and the second SCell (e.g., SCell 2) lack both SSB and TRS. In this case, the Pcell, the first SCell, and the second SCell can be co-located with MRTD similar to that used for intra-band CA deployment.

[0100] The second cell configuration 400-b shows a PCell with SSB, where both the first SCell (e.g., SCell 1) and the second SCell (e.g., SCell 2) lack SSB, and both the first SCell and the second SCell contain TRS. In this case, the Pcell, the first SCell, and the second SCell can be co-located, and the MRTD between the PCell and the SCell can be similar to or less than the MRTD for intra-band CA deployment.

[0101] The third cell configuration 400-c shows a PCell with SSB, where both the first SCell (e.g., SCell 1) and the second SCell (e.g., SCell 2) lack SSB. In some such cases, the first SCell may lack TRS and the second SCell may include TRS. In this case, the Pcell, the first SCell, and the second SCell may be co-located, and the MRTD between the PCell and the SCell may be similar to or less than the MRTD for intra-band CA deployment.

[0102] A fourth cell configuration 400-d shows a PCell with SSBs, where a first SCell (e.g., SCell 1) lacks SSBs and a second SCell (e.g., SCell 2) includes SSBs. In some such cases, both the first SCell and the second SCell may include TRSs. In this case, the Pcell, the first SCell, and the second SCell may be co-located, and the MRTD between the PCell and the SCell may be similar to or less than the MRTD for intra-band CA deployments.

[0103] In some aspects, the network may save both power and resources by disabling transmission of SSBs on at least some of the downlink cells (e.g., the first SCell and the second SCell) that are transmitted to the network node. However, the SSB for a cell or carrier may be used to set a QCL relationship for the network node to receive reference signaling on the cell. Thus, for implementations in which a non-SSB carrier is used, the network node may implement a variety of techniques for identifying a QCL source for receiving signaling (such as reference signaling) on ​​the non-SSB carrier.

[0104] Figure 5Example cell configurations 500-a, 500-b, and 500-c supporting reference signal transmission in enhanced CA according to one or more aspects of the present disclosure are illustrated. In some aspects, the cell configurations 500-a, 500-b, and 500-c may be implemented at or by one or more devices described herein. For example, the cell configurations 500-a, 500-b, and 500-c may be implemented at or by a network node such as a UE or a network entity, or both.

[0105] In some aspects, cell configurations 500-a, 500-b, and 500-c may support inter-band CA for carriers that do not have associated SSBs (e.g., SSB-free carriers). In some aspects, a network node may determine a QCL source for receiving communications on a SSB-free carrier or cell. In such examples, the QCL source may be a signal where properties of a wireless channel on which a signal is received may be applied to receiving a different signal on a different channel.

[0106] The first cell configuration 500-a shows a first cell (e.g., PCell 505-a) and a second cell (SCell 510-a) that can perform inter-band carrier aggregation. The network node can receive SSB 515-a on PCell 505-a and may not receive SSB on SCell 510-a. In some such cases, the network node can use the SSB 515-a received on PCell 505-a as a QCL source for receiving P-TRS 520-a to receive periodic TRS (e.g., P-TRS 520-a) on SCell 510-a. Additionally or alternatively, the network node can determine time and frequency synchronization information for SCell 510-a based on the SSB 515-a received on PCell 505-a. The network node may then receive the A-TRS (e.g., A-TRS 525-a) using the P-TRS 520-a as a QCL source for receiving the A-TRS 525-a. For example, the SSB 515-a may be a QCL source for the P-TRS 520-a, and the P-TRS 520-a may be a QCL source for the A-TRS 525-a. The SCell 510-a may be activated based on receiving the P-TRS 520-a and the A-TRS 525-a.

[0107] The second cell configuration 500-b shows a first cell (e.g., PCell 505-b) and a second cell (SCell 510-b) that may perform inter-band carrier aggregation. The network node may receive SSB 515-b on PCell 505-b and may not receive SSB on SCell 510-b. In some such cases, the network node may use the received SSB 515-b as a QCL source to receive P-TRS (e.g., P-TRS 520-b) on PCell 505-b. The network node may then receive A-TRS (e.g., A-TRS 525-b) using P-TRS 520-b as a QCL source for receiving A-TRS 525-b. For example, SSB515-b can be a QCL source for P-TRS 520-b, and P-TRS 520-b (received on PCell 505-b) can be a QCL source for A-TRS 525-b (received on SCell 510-b). SCell 510-b can be activated based on receiving P-TRS 520-b and A-TRS 525-b. Additionally or alternatively, the network node can determine time and frequency synchronization information for SCell 510-b based on P-TRS 520-b received on PCell 505-b.

[0108] The third cell configuration 500-c shows a first cell (e.g., PCell 505-c) and a second cell (SCell 510-c) that can perform inter-band carrier aggregation. The network node can receive SSB 515-c on PCell 505-c and may not receive SSB on SCell 510-c. In some such cases, the network node can use the received SSB 515-c as a QCL source to receive A-TRS (e.g., A-TRS 520-c) on SCell 510-c. For example, the SSB 515-c received on PCell 510-c can be a QCL source for A-TRS 520-c received on SCell 505-c. Additionally or alternatively, the network node can determine time and frequency synchronization information for SCell 510-c based on the SSB 515-c received on PCell 505-c.

[0109] Figure 6Example cell configurations 600-a and 600-b supporting reference signal transmission in enhanced CA according to one or more aspects of the present disclosure are illustrated. In some aspects, the cell configurations 600-a and 600-b may be implemented at or by one or more devices described herein. For example, the cell configurations 600-a and 600-b may be implemented at or by a network node such as a UE or a network entity, or both.

[0110] In some aspects, cell configurations 600-a and 600-b may be part of the same frequency band and support inter-band CA for carriers that do not have associated SSBs (e.g., SSB-free carriers). In some aspects, a network node may determine a QCL source for receiving communications on a SSB-free carrier or cell. In such examples, the QCL source may be a signal where properties of a wireless channel on which a signal is received may be applied to receiving a different signal on a different channel.

[0111] The first cell configuration 600-a shows a first cell (e.g., PCell 605-a), a first secondary cell (SCell 610-a), and a second secondary cell (SCell 615-a) that can perform inter-band carrier aggregation. The network node can receive SSBs on the PCell 605-a, and may not receive SSBs on the SCells 610-a and 615-a. In some such cases, the network node can receive TRS 620-a on the SCell 615-a, and may not receive TRS 620-a on the SCell 610-a. In some aspects, where the network node receives TRS 620-a on one carrier or cell but not on another carrier or cell, the received TRS 620-a can be shared between the two carriers or cells so that the TRS 620-a on one cell provides time and frequency tracking information for another cell. For example, TRS 620-a received on SCell 620-a may be shared between SCell 615-a and 620-a, and time and frequency tracking information for SCell 615-a may be provided. Additionally or alternatively, the network node may receive TRS 620-a using SSBs received on PCell 605-a as a QCL source for receiving TRS on SCell 615-a. In some aspects, the network node may receive communications on SCell 610-a using TRS 620-a as a QCL source for receiving communications on SCell 610-a.

[0112] The second cell configuration 600-a shows a first cell (e.g., PCell 605-b), a first secondary cell (SCell 610-b), and a second secondary cell (SCell 615-b) that can perform inter-band carrier aggregation. The network node can receive SSBs on PCell 605-b and can receive SSBs on SCell 615-b, and may not receive SSBs on SCell 610-b. In some such cases, the network node can receive TRS 620-b on SCell 610-b, and may not receive TRS 620-a on SCell 615-b. In some aspects, where the network node receives TRS 620-b on one carrier or cell but not on another carrier or cell, the received TRS 620-b can be shared between the two carriers or cells so that the TRS 620-b on one cell provides time and frequency tracking information for another cell. For example, TRS 620-b received on SCell 615-b may be shared between SCell 615-b and 610-b and may provide time and frequency tracking information for SCell 615-b (in addition to or in lieu of time frequency information provided by SSBs received on SCell 610-b). Additionally or alternatively, the network node may receive TRS 620-b using SSBs received on SCell 615-b as a QCL source. In some aspects, the network node may receive communications on SCell 610-a using TRS 620-b as a QCL source.

[0113] In some cases, the shared TRS 620-a and 620-b can reduce signaling overhead (e.g., the second network node can skip transmitting the TRS on every carrier and can transmit the TRS on the selected carrier), which can reduce resource usage. Additionally or alternatively, the second network node can increase the amount of time spent in idle or sleep mode based on the reduced SSB signaling, which can reduce overall network power consumption.

[0114] Figure 7An example of a process flow 700 for supporting reference signal transmission in enhanced CA according to one or more aspects of the present disclosure is illustrated. The process flow 700 may illustrate communications between network nodes, which may be examples of devices such as the first network node 115 and the network entity 105 described herein. For example, the process flow may be an example of a communication flow between the first network node 115-b and the network entities 105-d, 105-e, and 105-f. In the following description of the process flow 700, operations between devices may be communicated in an order different from the example order shown, or operations performed by the devices may be performed in a different order or at a different time. Some operations may also be omitted from the process flow 700, and other operations may be added to the process flow 700.

[0115] At 705, the first network node 115-b may receive a first message including information indicating an inter-band CA configuration that identifies a set of cells for communication by the first network node 115-a (e.g., served by network entities 105-d, 105-e, and 105-f, respectively).

[0116] At 715, the first network node 115-b may receive a synchronization signal on a first cell in the set of cells via a wireless channel 710 having a first set of channel attributes. In some aspects, the first cell and the second cell are aligned in time according to a threshold receive timing difference. In some aspects, the first cell and the second cell include a primary cell and a secondary cell, the primary cell and the secondary cell being co-located and occupying different frequency bands of an inter-band CA configuration.

[0117] In some aspects, at 720, the first network node 115-b may receive a first reference signal of the one or more reference signals on a first cell, wherein a synchronization signal of the first cell is a first QCL for the first reference signal. Then, at 725, in addition to the one or more reference signals, the network node may receive a second reference signal on a second cell, wherein the first reference signal of the first cell is a second QCL source indicating the second reference signal is received using a second set of QCL parameters. In some examples, the one or more reference signals include a TRS, such as a periodic CSI-RS for tracking and an aperiodic CSI-RS for tracking, a CSI-RS, or any combination thereof.

[0118] In some aspects, at 725, the first network node 115-b may receive a first reference signal from among the one or more reference signals on a second cell in the set of cells, wherein a synchronization signal of the first cell is a first QCL source for the first reference signal. Then, in addition to the one or more reference signals, the network node may receive a second reference signal on a second cell in the set of cells, wherein the first reference signal of the second cell is a second QCL source indicating that the second reference signal is received using a second set of QCL parameters. In some aspects, the first network node 115-b may receive the first reference signal and the second reference signal based on time and frequency synchronization information indicated by the synchronization signal of the first cell. In some aspects, the first QCL source or the second QCL source is a source of one or more Doppler shift parameters, one or more Doppler spread parameters, one or more average delay parameters, one or more delay spread parameters, one or more spatial receiver parameters, or any combination thereof.

[0119] At 730, the first network node 115-b may receive a first reference signal of the one or more reference signals on a third cell, wherein a synchronization signal of the first cell is a first QCL source indicating that the first reference signal is received using a first set of QCL parameters. The first network node 115-b may then receive one or more communications on a second cell in the set of cells, wherein the first reference signal of the third cell is a second QCL source indicating that the one or more communications are received using a second set of QCL parameters. In some aspects, the first reference signal on the third cell may be a shared reference signal between the second cell and the third cell.

[0120] In some aspects, the first network node 115-b may receive a second synchronization signal and a first reference signal on a third cell, wherein the second synchronization signal of the third cell is a first QCL source for the first reference signal. The first network node 115-b may then receive one or more communications on the second cell, wherein the second synchronization signal is the first QCL source indicating that one or more communications are to be received using a first set of QCL parameters, or the first reference signal is the second QCL source indicating that one or more communications are to be received using a second set of QCL parameters. In some aspects, the first reference signal on the third cell may be a shared reference signal between the second cell and the third cell.

[0121] At 735, the first network node 115-b may receive one or more reference signals on a second cell in the set of cells based on a first set of QCL parameters including a first set of channel attributes, wherein the first set of channel attributes is used based on a synchronization signal of the first cell, which synchronization signal of the first cell is a first QCL source indicating the use of the first set of QCL parameters to receive one or more reference signals.

[0122] Figure 8 A block diagram 800 of a device 805 supporting reference signal transmission in enhanced CA according to one or more aspects of the present disclosure is shown. The device 805 may be an example of aspects of a network node (such as a UE 115) as described herein. The device 805 may include a receiver 810, a transmitter 815, and a communication manager 820. The device 805 may also include a processor. Each of these components may communicate with each other (e.g., via one or more buses).

[0123] The receiver 810 may provide means for receiving information such as packets associated with various information channels (e.g., control channels, data channels, information channels related to reference signal transmission in enhanced CA), user data, control information, or any combination thereof. The information may be communicated to other components of the device 805. The receiver 810 may utilize a single antenna or a collection of multiple antennas.

[0124] The transmitter 815 may provide means for transmitting signals generated by other components of the device 805. For example, the transmitter 815 may transmit information such as packets associated with various information channels (e.g., control channels, data channels, information channels related to reference signal transmission in enhanced CA), user data, control information, or any combination thereof. In some aspects, the transmitter 815 may be co-located with the receiver 810 in a transceiver module. The transmitter 815 may utilize a single antenna or a collection of multiple antennas.

[0125] The communication manager 820, the receiver 810, the transmitter 815, or various combinations thereof, or various components thereof may be examples of means for performing various aspects of enhanced reference signal transmission in CA as described herein. For example, the communication manager 820, the receiver 810, the transmitter 815, or various combinations thereof, or components thereof may support methods for performing one or more of the functions described herein.

[0126] In some aspects, the communication manager 820, the receiver 810, the transmitter 815, or various combinations thereof or components thereof may be implemented in hardware (e.g., in a communication management circuit system). The hardware may include a processor, a digital signal processor (DSP), a central processing unit (CPU), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device, a microcontroller, discrete gate or transistor logic, discrete hardware components, or any combination thereof that is configured to or otherwise supports components for performing the functions described in the present disclosure. In some aspects, the processor and a memory coupled to the processor may be configured to perform one or more of the functions described herein (e.g., by executing instructions stored in the memory by the processor).

[0127] Additionally or alternatively, in some examples, the communication manager 820, the receiver 810, the transmitter 815, or various combinations thereof, or components thereof, may be implemented in code executed by a processor (e.g., as communication management software or firmware). If implemented in code executed by a processor, the functionality of the communication manager 820, the receiver 810, the transmitter 815, or various combinations thereof, or components thereof may be performed by a general purpose processor (e.g., configured as or otherwise supporting means for performing the functions described in the present disclosure), a DSP, a CPU, an ASIC, an FPGA, a microcontroller, or any combination of these or other programmable logic devices.

[0128] In some aspects, the communication manager 820 can be configured to perform various operations (e.g., receive, obtain, monitor, output, transmit) using or otherwise cooperating with the receiver 810, the transmitter 815, or both. For example, the communication manager 820 can receive information from the receiver 810, transmit information to the transmitter 815, or integrate with the receiver 810, the transmitter 815, or both to obtain information, output information, or perform various other operations as described herein.

[0129] The communication manager 820 may support wireless communications at a network node according to an example as disclosed herein. For example, the communication manager 820 may be configured to or otherwise support a component for receiving a first message including information indicating an inter-band CA configuration, the inter-band CA configuration identifying a set of cells for communication by the network node. The communication manager 820 may be configured to or otherwise support a component for receiving a synchronization signal on a first cell in the set of cells via a wireless channel having a first set of channel attributes. The communication manager 820 may be configured to or otherwise support a component for receiving one or more reference signals on a second cell in the set of cells based on a first set of QCL parameters, the first set of QCL parameters being used based on a synchronization signal of the first cell, the synchronization signal of the first cell being a first QCL source indicating the use of the first set of QCL parameters to receive one or more reference signals.

[0130] By including or configuring the communication manager 820 according to the examples described herein, the device 805 (e.g., a processor controlling or otherwise coupled to the receiver 810, the transmitter 815, the communication manager 820, or a combination thereof) can support techniques for reducing power consumption due to reduced signaling and more efficient time and frequency synchronization procedures that use relatively less network signaling.

[0131] Fig. 9 A block diagram 900 of a device 905 supporting reference signal transmission in enhanced CA according to one or more aspects of the present disclosure is shown. The device 905 may be an example of aspects of the device 805 or UE 115 as described herein. The device 905 may include a receiver 910, a transmitter 915, and a communication manager 920. The device 905 may also include a processor. Each of these components may communicate with each other (e.g., via one or more buses).

[0132] The receiver 910 may provide means for receiving information such as packets associated with various information channels (e.g., control channels, data channels, information channels related to reference signal transmission in enhanced CA), user data, control information, or any combination thereof. The information may be communicated to other components of the device 905. The receiver 910 may utilize a single antenna or a collection of multiple antennas.

[0133] The transmitter 915 may provide means for transmitting signals generated by other components of the device 905. For example, the transmitter 915 may transmit information such as packets associated with various information channels (e.g., control channels, data channels, information channels related to reference signal transmission in enhanced CA), user data, control information, or any combination thereof. In some aspects, the transmitter 915 may be co-located with the receiver 910 in a transceiver module. The transmitter 915 may utilize a single antenna or a collection of multiple antennas.

[0134] The device 905 or its various components may be examples of means for performing various aspects of reference signal transmission in enhanced CA as described herein. For example, the communication manager 920 may include a CA configuration component 925, a synchronization signal receiving component 930, a first QCL source receiving component 935, or any combination thereof. The communication manager 920 may be an example of various aspects of the communication manager 820 as described herein. In some aspects, the communication manager 920 or its various components may be configured to perform various operations (e.g., receive, obtain, monitor, output, transmit) using or otherwise in conjunction with the receiver 910, the transmitter 915, or both. For example, the communication manager 920 may receive information from the receiver 910, transmit information to the transmitter 915, or be integrated with the receiver 910, the transmitter 915, or both to obtain information, output information, or perform various other operations as described herein.

[0135] The communication manager 920 may support wireless communications at a network node according to an example as disclosed herein. The CA configuration component 925 may be configured to or otherwise support a component for receiving a first message including information indicating an inter-band CA configuration, the inter-band CA configuration identifying a set of cells for communication by the network node. The synchronization signal receiving component 930 may be configured to or otherwise support a component for receiving a synchronization signal on a first cell in a set of cells via a wireless channel having a first set of channel attributes. The first QCL source receiving component 935 may be configured to or otherwise support a component for receiving one or more reference signals on a second cell in a set of cells based on a first set of QCL parameters including a first set of channel attributes, the first set of QCL parameters being used based on a synchronization signal of the first cell, the synchronization signal of the first cell being a first QCL source indicating the use of the first set of QCL parameters to receive one or more reference signals.

[0136] Fig.10A block diagram 1000 of a communication manager 1020 supporting reference signal transmission in enhanced CA according to one or more aspects of the present disclosure is shown. The communication manager 1020 can be an example of aspects of the communication manager 820, the communication manager 920, or both as described herein. The communication manager 1020 or its various components can be examples of means for performing aspects of reference signal transmission in enhanced CA as described herein. For example, the communication manager 1020 can include a CA configuration component 1025, a synchronization signal receiving component 1030, a first QCL source receiving component 1035, a second QCL source receiving component 1040, a communication receiving component 1045, a time and frequency synchronization component 1050, or any combination thereof. Each of these components can communicate with each other directly or indirectly (e.g., via one or more buses).

[0137] The communication manager 1020 may support wireless communications at a network node according to an example as disclosed herein. The CA configuration component 1025 may be configured to or otherwise support a component for receiving a first message including information indicating an inter-band CA configuration, the inter-band CA configuration identifying a set of cells for communication by the network node. The synchronization signal receiving component 1030 may be configured to or otherwise support a component for receiving a synchronization signal on a first cell in the set of cells via a wireless channel having a first set of channel attributes. The first QCL source receiving component 1035 may be configured to or otherwise support a component for receiving one or more reference signals on a second cell in the set of cells based on a first set of QCL parameters including a first set of channel attributes, the first set of QCL parameters being used based on a synchronization signal of the first cell, the synchronization signal of the first cell being a first QCL source indicating the use of the first set of QCL parameters to receive one or more reference signals.

[0138] In some aspects, the first QCL source receiving component 1035 can be configured to or otherwise support means for receiving a first reference signal of the one or more reference signals on a second cell in the set of cells, wherein a synchronization signal of the first cell is a first QCL source indicating that the first reference signal is received using a first set of QCL parameters. In some aspects, the second QCL source receiving component 1040 can be configured to or otherwise support means for receiving a second reference signal on a second cell in the set of cells in addition to the one or more reference signals, wherein the first reference signal of the second cell is a second QCL source indicating that the second reference signal is received using a second set of QCL parameters.

[0139] In some aspects, time and frequency synchronization component 1050 may be configured or otherwise support means for receiving a first reference signal and a second reference signal of one or more reference signals based on time and frequency synchronization information indicated by a synchronization signal of a first cell.

[0140] In some aspects, the first set of QCL parameters, the second set of QCL parameters, or both are associated with one or more Doppler shift parameters, one or more Doppler spread parameters, one or more average delay parameters, one or more delay spread parameters, one or more spatial receiver parameters, or any combination thereof.

[0141] In some aspects, the first QCL source receiving component 1035 can be configured to or otherwise support means for receiving a first reference signal of the one or more reference signals on a first cell in the set of cells, wherein a synchronization signal of the first cell is a first QCL source indicating that the first reference signal is received using a first set of QCL parameters. In some aspects, the second QCL source receiving component 1040 can be configured to or otherwise support means for receiving a second reference signal on a second cell in the set of cells in addition to the one or more reference signals, wherein the first reference signal of the first cell is a second QCL source indicating that the second reference signal is received using a second set of QCL parameters.

[0142] In some aspects, the time and frequency synchronization component 1050 may be configured or otherwise support means for receiving a first reference signal and a second reference signal of one or more reference signals on a second cell based on time and frequency synchronization information indicated by a synchronization signal of the first cell.

[0143] In some aspects, the first set of QCL parameters, the second set of QCL parameters, or both are associated with one or more Doppler shift parameters, one or more Doppler spread parameters, one or more average delay parameters, one or more delay spread parameters, one or more spatial receiver parameters, or any combination thereof.

[0144] In some aspects, the first QCL source receiving component 1035 can be configured to or otherwise support a component for receiving a first reference signal among one or more reference signals on a second cell in a set of cells, wherein a synchronization signal of the first cell is indicative of a first QCL source for receiving the first reference signal using a first set of QCL parameters.

[0145] In some aspects, time and frequency synchronization component 1050 may be configured or otherwise support means for receiving a first reference signal of one or more reference signals on a second cell based on time and frequency synchronization information indicated by a synchronization signal of the first cell.

[0146] In some aspects, the first QCL source is a source of one or more Doppler shift parameters, one or more Doppler spread parameters, one or more average delay parameters, one or more delay spread parameters, one or more spatial receiver parameters, or any combination thereof.

[0147] In some aspects, the first QCL source receiving component 1035 can be configured to or otherwise support means for receiving a first reference signal of the one or more reference signals on a third cell in the set of cells, wherein the synchronization signal of the first cell is a first QCL source indicating the first set of QCL parameters to be used to receive the first reference signal. In some aspects, the second QCL source receiving component 1040 can be configured to or otherwise support means for receiving one or more communications on a second cell in the set of cells, wherein the first reference signal of the third cell is a second QCL source indicating the first set of QCL parameters to be used to receive the one or more communications.

[0148] In some aspects, time and frequency synchronization component 1050 may be configured or otherwise support means for receiving a first reference signal on a third cell and one or more communications on a second cell based on time and frequency synchronization information indicated by a synchronization signal of the first cell.

[0149] In some aspects, the first set of QCL parameters, the second set of QCL parameters, or both are associated with one or more Doppler shift parameters, one or more Doppler spread parameters, one or more average delay parameters, one or more delay spread parameters, one or more spatial receiver parameters, or any combination thereof.

[0150] In some aspects, the first QCL source receiving component 1035 can be configured to or otherwise support means for receiving a second synchronization signal and a first reference signal in one or more reference signals on a third cell in the set of cells, wherein the second synchronization signal of the third cell is a first QCL source for the first reference signal. In some aspects, the communication receiving component 1045 can be configured to or otherwise support means for receiving one or more communications on a second cell in the set of cells, wherein the second synchronization signal is a first QCL source indicating the use of a first set of QCL parameters to receive the one or more communications, or wherein the first reference signal is a second QCL source indicating the use of a second set of QCL parameters to receive the one or more communications.

[0151] In some aspects, the communication receiving component 1045 may be configured or otherwise support means for receiving one or more communications on the second cell based on the time and frequency synchronization information indicated by the first synchronization signal of the first cell. In some aspects, the time and frequency synchronization component 1050 may be configured or otherwise support means for receiving the first reference signal on the third cell based on the additional time and frequency synchronization information indicated by the second synchronization signal of the second cell.

[0152] In some aspects, the first set of QCL parameters, the second set of QCL parameters, or both are associated with one or more Doppler shift parameters, one or more Doppler spread parameters, one or more average delay parameters, one or more delay spread parameters, one or more average delay parameters, one or more delay spread parameters, one or more spatial receiver parameters, or any combination thereof.

[0153] In some aspects, the first cell and the second cell are aligned in time according to a threshold receive timing difference.

[0154] In some aspects, the first cell and the second cell comprise a combination of a primary cell and a secondary cell, the primary cell and the secondary cell being co-located and occupying different frequency bands of an inter-band CA configuration.

[0155] In some aspects, the one or more reference signals include a P-TRS, an A-TRS, or both. In some aspects, the one or more reference signals include a channel state information reference signal.

[0156] Fig.11 A diagram of a system 1100 including a device 1105 supporting reference signal transmission in enhanced CA according to one or more aspects of the present disclosure is shown. The device 1105 may be an example of a device 805, a device 905, or a UE 115 as described herein, or include components thereof. The device 1105 may communicate (e.g., wirelessly) with one or more network entities 105, one or more UEs 115, or any combination thereof. The device 1105 may include components for two-way voice and data communications, including components for sending and receiving communications, such as a communication manager 1120, an input / output (I / O) controller 1110, a transceiver 1115, an antenna 1125, a memory 1130, a code 1135, and a processor 1140. These components may be electronically communicated or otherwise coupled (e.g., operatively, communicatively, functionally, electronically, electrically) via one or more buses (e.g., a bus 1145).

[0157] I / O controller 1110 can manage input and output signals for device 1105. I / O controller 1110 can also manage peripheral devices that are not integrated into device 1105. In some cases, I / O controller 1110 can represent a physical connection or port to an external peripheral device. In some cases, I / O controller 1110 can utilize an operating system, such as or another known operating system. Additionally or alternatively, I / O controller 1110 may represent or interact with a modem, keyboard, mouse, touch screen, or similar device. In some cases, I / O controller 1110 may be implemented as part of a processor (such as processor 1140). In some cases, a user may interact with device 1105 via I / O controller 1110 or via hardware components controlled by I / O controller 1110.

[0158] In some cases, the device 1105 may include a single antenna 1125. However, in some other cases, the device 1105 may have more than one antenna 1125, which may be capable of concurrently transmitting or receiving multiple wireless transmissions. The transceiver 1115 may communicate bidirectionally via one or more antennas 1125, a wired or wireless link, as described herein. For example, the transceiver 1115 may represent a wireless transceiver and may communicate bidirectionally with another wireless transceiver. The transceiver 1115 may also include a modem for: modulating packets; providing the modulated packets to one or more antennas 1125 for transmission; and demodulating packets received from one or more antennas 1125. The transceiver 1115 or the transceiver 1115 and one or more antennas 1125 may be examples of transmitters 815, transmitters 915, receivers 810, receivers 910, or any combination thereof or components thereof as described herein.

[0159] The memory 1130 may include random access memory (RAM) and read-only memory (ROM). The memory 1130 may store computer-readable, computer-executable code 1135 including instructions that, when executed by the processor 1140, cause the device 1105 to perform various functions described herein. The code 1135 may be stored in a non-transitory computer-readable medium, such as a system memory or another type of memory. In some cases, the code 1135 may not be directly executable by the processor 1140, but may (e.g., when compiled and executed) cause the computer to perform the functions described herein. In some cases, the memory 1130 may also contain, among other things, a basic I / O system (BIOS) that may control basic hardware or software operations, such as interaction with peripheral components or devices.

[0160] The processor 1140 may include an intelligent hardware device (e.g., a general-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, an FPGA, a programmable logic device, a discrete gate or transistor logic component, a discrete hardware component, or any combination thereof). In some cases, the processor 1140 may be configured to operate a memory array using a memory controller. In some other cases, the memory controller may be integrated into the processor 1140. The processor 1140 may be configured to execute computer-readable instructions stored in a memory (e.g., a memory 1130) to enable the device 1105 to perform various functions (e.g., various functions or tasks to support reference signal transmission in enhanced CA). For example, the device 1105 or a component of the device 1105 may include a processor 1140 and a memory 1130 coupled to or coupled to the processor 1140, and the processor 1140 and the memory 1130 are configured to perform the various functions described herein.

[0161] The communication manager 1120 may support wireless communications at a network node according to an example as disclosed herein. For example, the communication manager 1120 may be configured to or otherwise support a component for receiving a first message including information indicating an inter-band CA configuration, the inter-band CA configuration identifying a set of cells for communication by the network node. The communication manager 1120 may be configured to or otherwise support a component for receiving a synchronization signal on a first cell in the set of cells via a wireless channel having a first set of channel attributes. The communication manager 1120 may be configured to or otherwise support a component for receiving one or more reference signals on a second cell in the set of cells based on a first set of QCL parameters including a first set of channel attributes, the first set of QCL parameters being used based on a synchronization signal of the first cell, the synchronization signal of the first cell being a first QCL source indicating the use of the first set of QCL parameters to receive one or more reference signals.

[0162] By including or configuring the communication manager 1120 according to the examples described herein, the device 1105 can support techniques for improving communication reliability based on synchronization, reducing power consumption due to reduced signaling, and more efficient time and frequency synchronization procedures using relatively less network signaling, more efficient communication resource utilization, extending battery life due to reduced power consumption, and reducing network burden.

[0163] In some aspects, the communication manager 1120 may be configured to perform various operations (e.g., receive, monitor, transmit) using or otherwise cooperating with the transceiver 1115, one or more antennas 1125, or any combination thereof. Although the communication manager 1120 is illustrated as a separate component, in some examples, one or more functions described with reference to the communication manager 1120 may be supported or performed by the processor 1140, the memory 1130, the code 1135, or any combination thereof. For example, the code 1135 may include instructions that may be executed by the processor 1140 to cause the device 1105 to perform various aspects of reference signal transmission in enhanced CA as described herein, or the processor 1140 and the memory 1130 may be otherwise configured to perform or support such operations.

[0164] Fig.12 A flowchart illustrating a method 1200 for supporting reference signal transmission in enhanced CA according to one or more aspects of the present disclosure is shown. The operations of the method 1200 may be implemented by a UE or a component thereof as described herein. For example, the operations of the method 1200 may be implemented by a UE or a component thereof as described herein. Figures 1 to 11 The described functions may be performed by the UE 115. In some aspects, the UE may execute a set of instructions to control the functional elements of the UE to perform the described functions. Additionally or alternatively, the UE may use dedicated hardware to perform various aspects of the described functions.

[0165] At 1205, the method may include receiving a first message including information indicating an inter-band CA configuration, the inter-band CA configuration identifying a set of cells for communication by the network node. The operations of 1205 may be performed according to examples as disclosed herein. In some aspects, aspects of the operations of 1205 may be performed as described in reference to Fig.10 The described CA configuration component 1025 performs.

[0166] At 1210, the method may include receiving a synchronization signal on a first cell in the set of cells via a wireless channel having a first set of channel properties. The operations of 1210 may be performed according to examples as disclosed herein. In some aspects, aspects of the operations of 1210 may be performed as described in reference to Fig.10 The described synchronization signal receiving component 1030 performs.

[0167] At 1215, the method may include: receiving one or more reference signals on a second cell in the set of cells based on a first set of QCL parameters including a first set of channel attributes, the first set of QCL parameters being used based on a synchronization signal of the first cell, the synchronization signal of the first cell being a first QCL source indicating the use of the first set of QCL parameters to receive the one or more reference signals. The operations of 1215 may be performed according to examples as disclosed herein. In some aspects, aspects of the operations of 1215 may be performed by a method as described in reference to Fig.10 The described first QCL source receiving component 1035 performs.

[0168] Fig.13 A flowchart illustrating a method 1300 for supporting reference signal transmission in enhanced CA according to one or more aspects of the present disclosure is shown. The operations of the method 1300 may be implemented by a UE or a component thereof as described herein. For example, the operations of the method 1300 may be implemented by a UE or a component thereof as described herein. Figures 1 to 11 The described functions may be performed by the UE 115. In some aspects, the UE may execute a set of instructions to control the functional elements of the UE to perform the described functions. Additionally or alternatively, the UE may use dedicated hardware to perform various aspects of the described functions.

[0169] At 1305, the method may include receiving a first message including information indicating an inter-band CA configuration, the inter-band CA configuration identifying a set of cells for communication by the network node. The operations of 1305 may be performed according to examples as disclosed herein. In some aspects, aspects of the operations of 1305 may be performed as described in reference to Fig.10 The described CA configuration component 1025 performs.

[0170] At 1310, the method may include receiving a synchronization signal on a first cell in the set of cells via a wireless channel having a first set of channel properties. The operations of 1310 may be performed according to examples as disclosed herein. In some aspects, aspects of the operations of 1310 may be performed as described in reference to Fig.10 The described synchronization signal receiving component 1030 performs.

[0171] At 1315, the method may include: receiving one or more reference signals on a second cell in the set of cells based on a first set of QCL parameters including a first set of channel attributes, the first set of QCL parameters being used based on a synchronization signal of the first cell, the synchronization signal of the first cell being a first QCL source indicating the use of the first set of QCL parameters to receive the one or more reference signals. The operations of 1315 may be performed according to examples as disclosed herein. In some aspects, aspects of the operations of 1315 may be performed by a method as described in reference to Fig.10The described first QCL source receiving component 1035 performs.

[0172] At 1320, the method may include: receiving a first reference signal of the one or more reference signals on a second cell in the set of cells, wherein the synchronization signal of the first cell is a first QCL source indicating that the first reference signal is received using a first set of QCL parameters. The operations of 1320 may be performed according to examples as disclosed herein. In some aspects, aspects of the operations of 1320 may be performed by the reference Fig.10 The described first QCL source receiving component 1035 performs.

[0173] At 1325, the method may include: receiving a second reference signal on a second cell in the set of cells in addition to the one or more reference signals, wherein the first reference signal of the second cell is a second QCL source indicating that the second reference signal is received using a second set of QCL parameters. The operations of 1325 may be performed according to examples as disclosed herein. In some aspects, aspects of the operations of 1325 may be performed by the reference Fig.10 The described second QCL source receiving component 1040 performs.

[0174] Fig.14 A flowchart illustrating a method 1400 for supporting reference signal transmission in enhanced CA according to one or more aspects of the present disclosure is shown. The operations of the method 1400 may be implemented by a UE or a component thereof as described herein. For example, the operations of the method 1400 may be implemented by a UE or a component thereof as described herein. Figures 1 to 11 The described functions may be performed by the UE 115. In some aspects, the UE may execute a set of instructions to control the functional elements of the UE to perform the described functions. Additionally or alternatively, the UE may use dedicated hardware to perform various aspects of the described functions.

[0175] At 1405, the method may include receiving a first message including information indicating an inter-band CA configuration, the inter-band CA configuration identifying a set of cells for communication by a network node. The operations of 1405 may be performed according to examples as disclosed herein. In some aspects, aspects of the operations of 1405 may be performed as described in reference to Fig.10 The described CA configuration component 1025 performs.

[0176] At 1410, the method may include receiving a synchronization signal on a first cell in the set of cells via a wireless channel having a first set of channel properties. The operations of 1410 may be performed according to examples as disclosed herein. In some aspects, aspects of the operations of 1410 may be performed as described in reference to Fig.10 The described synchronization signal receiving component 1030 performs.

[0177] At 1415, the method may include: receiving one or more reference signals on a second cell in the set of cells based on a first set of QCL parameters including a first set of channel attributes, the first set of QCL parameters being used based on a synchronization signal of the first cell, the synchronization signal of the first cell being a first QCL source indicating the use of the first set of QCL parameters to receive the one or more reference signals. The operations of 1415 may be performed according to examples as disclosed herein. In some aspects, aspects of the operations of 1415 may be performed by a method as described in reference to Fig.10 The described first QCL source receiving component 1035 performs.

[0178] At 1420, the method may include: receiving a first reference signal of the one or more reference signals on a first cell in the set of cells, wherein a synchronization signal of the first cell is a first QCL source indicating that the first reference signal is received using a first set of QCL parameters. The operations of 1420 may be performed according to examples as disclosed herein. In some aspects, aspects of the operations of 1420 may be performed by the reference Fig.10 The described first QCL source receiving component 1035 performs.

[0179] At 1425, the method may include: receiving a second reference signal on a second cell in the set of cells in addition to the one or more reference signals, wherein the first reference signal of the first cell is a second QCL source indicating that the second reference signal is received using a second set of QCL parameters. The operations of 1425 may be performed according to examples as disclosed herein. In some aspects, aspects of the operations of 1425 may be performed by the reference Fig.10 The described second QCL source receiving component 1040 performs.

[0180] Fig.15 A flowchart illustrating a method 1500 for supporting reference signal transmission in enhanced CA according to one or more aspects of the present disclosure is shown. The operations of the method 1500 may be implemented by a UE or a component thereof as described herein. For example, the operations of the method 1500 may be implemented by a UE or a component thereof as described herein. Figures 1 to 11 The described functions may be performed by the UE 115. In some aspects, the UE may execute a set of instructions to control the functional elements of the UE to perform the described functions. Additionally or alternatively, the UE may use dedicated hardware to perform various aspects of the described functions.

[0181] At 1505, the method may include receiving a first message including information indicating an inter-band CA configuration, the inter-band CA configuration identifying a set of cells for communication by a network node. The operations of 1505 may be performed according to examples as disclosed herein. In some aspects, aspects of the operations of 1505 may be performed as described in reference to Fig.10The described CA configuration component 1025 performs.

[0182] At 1510, the method may include receiving a synchronization signal on a first cell in the set of cells via a wireless channel having a first set of channel properties. The operations of 1510 may be performed according to examples as disclosed herein. In some aspects, aspects of the operations of 1510 may be performed as described in reference to Fig.10 The described synchronization signal receiving component 1030 performs.

[0183] At 1515, the method may include: receiving one or more reference signals on a second cell in the set of cells based on a first set of QCL parameters including a first set of channel attributes, the first set of QCL parameters being used based on a synchronization signal of the first cell, the synchronization signal of the first cell being a first QCL source indicating the use of the first set of QCL parameters to receive the one or more reference signals. The operations of 1515 may be performed according to examples as disclosed herein. In some aspects, aspects of the operations of 1515 may be performed by a method as described in reference to Fig.10 The described first QCL source receiving component 1035 performs.

[0184] At 1520, the method may include: receiving a first reference signal of the one or more reference signals on a third cell in the set of cells, wherein the synchronization signal of the first cell is a first QCL source indicating that the first reference signal is received using a first set of QCL parameters. The operations of 1520 may be performed according to examples as disclosed herein. In some aspects, aspects of the operations of 1520 may be performed by the reference Fig.10 The described first QCL source receiving component 1035 performs.

[0185] At 1525, the method may include: receiving one or more communications on a second cell in the set of cells, wherein the first reference signal of the third cell is a second QCL source indicating the use of a second set of QCL parameters to receive the one or more communications. The operations of 1525 may be performed according to examples as disclosed herein. In some aspects, aspects of the operations of 1525 may be performed as described in reference to Fig.10 The described second QCL source receiving component 1040 performs.

[0186] Fig.16 A flowchart illustrating a method 1600 for supporting reference signal transmission in enhanced CA according to one or more aspects of the present disclosure is shown. The operations of the method 1600 may be implemented by a UE or a component thereof as described herein. For example, the operations of the method 1600 may be implemented by a UE or a component thereof as described herein. Figures 1 to 11The described functions may be performed by the UE 115. In some aspects, the UE may execute a set of instructions to control the functional elements of the UE to perform the described functions. Additionally or alternatively, the UE may use dedicated hardware to perform various aspects of the described functions.

[0187] At 1605, the method may include receiving a first message including information indicating an inter-band CA configuration, the inter-band CA configuration identifying a set of cells for communication by the network node. The operations of 1605 may be performed according to examples as disclosed herein. In some aspects, aspects of the operations of 1605 may be performed as described in reference to Fig.10 The described CA configuration component 1025 performs.

[0188] At 1610, the method may include receiving a synchronization signal on a first cell in the set of cells via a wireless channel having a first set of channel properties. The operations of 1610 may be performed according to examples as disclosed herein. In some aspects, aspects of the operations of 1610 may be performed as described in reference to Fig.10 The described synchronization signal receiving component 1030 performs.

[0189] At 1615, the method may include: receiving one or more reference signals on a second cell in the set of cells based on a first set of QCL parameters including a first set of channel attributes, the first set of QCL parameters being used based on a synchronization signal of the first cell, the synchronization signal of the first cell being a first QCL source indicating the use of the first set of QCL parameters to receive the one or more reference signals. The operations of 1615 may be performed according to examples as disclosed herein. In some aspects, aspects of the operations of 1615 may be performed by a method as described in reference to Fig.10 The described first QCL source receiving component 1035 performs.

[0190] At 1620, the method may include: receiving a second synchronization signal and a first reference signal from among the one or more reference signals on a third cell in the set of cells, wherein the second synchronization signal of the third cell is a first QCL source for the first reference signal. The operations of 1620 may be performed according to examples as disclosed herein. In some aspects, aspects of the operations of 1620 may be performed by the examples as disclosed herein. Fig.10 The described first QCL source receiving component 1035 performs.

[0191] At 1625, the method may include receiving one or more communications on a second cell in the set of cells, wherein the second synchronization signal is a first QCL source indicating the use of the first set of QCL parameters to receive the one or more communications, or wherein the first reference signal is a second QCL source indicating the use of the second set of QCL parameters to receive the one or more communications. The operations of 1625 may be performed according to examples as disclosed herein. In some aspects, aspects of the operations of 1625 may be performed by reference to Fig.10 The described communication receiving component 1045 executes.

[0192] The following provides an overview of various aspects of the disclosure:

[0193] Aspect 1: A method for performing wireless communications at a UE, the method comprising: receiving a first message, the first message comprising information indicating an inter-band carrier aggregation configuration, the inter-band carrier aggregation configuration identifying a set of cells used for communication by the network node; receiving a synchronization signal on a first cell in the set of cells via a wireless channel having a first set of channel attributes; and receiving one or more reference signals on a second cell in the set of cells based on a first set of QCL parameters including the first set of channel attributes, the first set of QCL parameters being used based on the synchronization signal of the first cell, the synchronization signal of the first cell being a first QCL source indicating the use of the first set of QCL parameters to receive the one or more reference signals.

[0194] Aspect 2: According to the method described in Aspect 1, the method further includes: receiving a first reference signal among the one or more reference signals on the second cell in the set of cells, wherein the synchronization signal of the first cell is the first QCL source indicating the use of the first set of QCL parameters to receive the first reference signal; and receiving a second reference signal on the second cell in the set of cells in addition to the one or more reference signals, wherein the first reference signal of the second cell is a second QCL source indicating the use of the second set of QCL parameters to receive the second reference signal.

[0195] Aspect 3: According to the method of aspect 2, the method further includes: receiving the first reference signal and the second reference signal among the one or more reference signals based on time and frequency synchronization information indicated by the synchronization signal of the first cell.

[0196] Aspect 4: A method according to any one of Aspects 2 to 3, wherein the first set of QCL parameters, the second set of QCL parameters, or both are associated with one or more Doppler shift parameters, one or more Doppler spread parameters, one or more average delay parameters, one or more delay spread parameters, one or more spatial receiver parameters, or any combination thereof.

[0197] Aspect 5: According to the method described in any one of Aspects 1 to 4, the method further includes: receiving a first reference signal among the one or more reference signals on the first cell in the set of cells, wherein the synchronization signal of the first cell is the first QCL source indicating the use of the first set of QCL parameters to receive the first reference signal; and receiving a second reference signal on the second cell in the set of cells in addition to the one or more reference signals, wherein the first reference signal of the first cell is a second QCL source indicating the use of the second set of QCL parameters to receive the second reference signal.

[0198] Aspect 6: According to the method described in any one of Aspects 1 to 5, the method further includes: receiving a first reference signal among the one or more reference signals on the second cell in the set of cells, wherein the synchronization signal of the first cell is the first QCL source indicating the use of the first set of QCL parameters to receive the first reference signal.

[0199] Aspect 7: According to the method described in any one of Aspects 1 to 6, the method further includes: receiving a first reference signal among the one or more reference signals on a third cell in the set of cells, wherein the synchronization signal of the first cell is a first QCL source indicating the use of the first set of QCL parameters to receive the first reference signal; and receiving one or more communications on the second cell in the set of cells, wherein the first reference signal of the third cell is a second QCL source indicating the use of the second set of QCL parameters to receive the one or more communications.

[0200] Aspect 8: According to the method described in any one of Aspects 1 to 7, the method further includes: receiving a second synchronization signal and a first reference signal among the one or more reference signals on a third cell in the set of cells, wherein the second synchronization signal of the third cell is the first QCL source indicating the use of the first set of QCL parameters to receive the first reference signal; and receiving one or more communications on the second cell in the set of cells, wherein the second synchronization signal is the first QCL source indicating the use of the first set of QCL parameters to receive the one or more communications, or wherein the first reference signal is the second QCL source indicating the use of the second set of QCL parameters to receive the one or more communications.

[0201] Aspect 9: According to the method described in any one of Aspects 1 to 8, the method further includes: receiving the one or more communications on the second cell based on the time and frequency synchronization information indicated by the first synchronization signal of the first cell; and receiving the first reference signal on the third cell based on the additional time and frequency synchronization information indicated by the second synchronization signal of the second cell.

[0202] Aspect 10: A network node for wireless communication, the network node comprising: a memory; and at least one processor, the at least one processor coupled to the memory, wherein the at least one processor is configured to perform the method according to any one of aspects 1 to 9.

[0203] Aspect 11: A network node for wireless communication, the network node comprising at least one component for performing the method according to any one of aspects 1 to 9.

[0204] Aspect 12: A non-transitory computer-readable medium having codes stored thereon, which, when executed by a network node, cause the network node to perform the method according to any one of aspects 1 to 9.

[0205] The methods described herein describe possible implementations, and the operations and steps may be rearranged or otherwise modified, and other implementations are possible. In addition, aspects from two or more methods may be combined.

[0206] Although aspects of LTE, LTE-A, LTE-A Pro, or NR systems may be described for example purposes, and LTE, LTE-A, LTE-A Pro, or NR terminology may be used in much of the description, the techniques described herein may also be applicable to networks other than LTE, LTE-A, LTE-A Pro, or NR networks. For example, the techniques described may be applicable to various other wireless communication systems, such as Ultra Mobile Broadband (UMB), Institute of Electrical and Electronics Engineers (IEEE) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, Flash-OFDM, and other systems and radio technologies not explicitly mentioned herein.

[0207] The information and signals described herein may be represented using any of a variety of different techniques and methods. For example, data, instructions, commands, information, signals, bits, symbols, and chips mentioned throughout the specification may be represented by voltage, current, electromagnetic waves, magnetic fields or magnetic particles, optical fields or optical particles, or any combination thereof.

[0208] The various illustrative blocks and components described in conjunction with the disclosure herein may be implemented or performed with a general purpose processor, DSP, ASIC, CPU, FPGA or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general purpose processor may be a microprocessor, but in an alternative, the processor may be any processor, controller, microcontroller, or state machine. The processor may also be implemented as a combination of computing devices (e.g., a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration).

[0209] The functions described herein can be implemented in hardware, software executed by a processor, firmware, or any combination thereof. When implemented in software executed by a processor, the functions can be stored as one or more instructions or codes on a computer-readable medium or sent via a computer-readable medium. Other examples and specific implementations are within the scope of the present disclosure and the appended claims. For example, due to the nature of software, the functions described herein can be implemented using software executed by a processor, hardware, firmware, hard wiring, or a combination of any of these items. The features that implement the functions can also be physically located at different locations, including being distributed so that the various parts of the functions are implemented at different physical locations.

[0210] Computer-readable medium includes both non-transient computer storage medium and communication medium, and the communication medium includes any medium that helps to transfer a computer program from one place to another place.Non-transient storage medium can be any available medium that can be accessed by a general or special computer.By way of example and not limitation, non-transient computer-readable medium can include RAM, ROM, electrically erasable programmable ROM (EEPROM), flash memory, compact disc (CD) ROM or other optical disc storage device, disk storage device or other magnetic storage device, or can be used for carrying or storing desired program code components and any other non-transient medium that can be accessed by a general or special computer or a general or special processor in the form of an instruction or data structure.In addition, any connection is appropriately referred to as computer-readable medium.For example, if software is sent from a website, server or other remote source using coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL) or wireless technologies such as infrared, radio and microwave, then coaxial cable, fiber optic cable, twisted pair, DSL or wireless technologies such as infrared, radio and microwave are included in the definition of computer-readable medium. As used herein, disk and disc include CD, laser disc, optical disc, digital versatile disc (DVD), floppy disk and Blu-ray disc, where disks usually reproduce data magnetically, while discs reproduce data optically with lasers. Combinations of the above are also included within the scope of computer-readable media.

[0211] As used herein (including in the claims), "or" used in a list of items (e.g., a list of items preceded by a phrase such as "at least one of" or "one or more of") indicates an inclusive list, so that, for example, a list of at least one of A, B, or C means A or B or C or AB or AC or BC or ABC (i.e., A and B and C). Moreover, as used herein, the phrase "based on" should not be interpreted as referring to a closed set of information, one or more conditions, one or more factors, etc. In other words, the phrase "based on A" (where "A" can be information, a condition, a factor, etc.) should be interpreted as "based on at least A" unless specifically stated differently.

[0212] The term "determine" or "determining" encompasses a wide variety of actions, and thus, "determining" may include calculating, computing, processing, deriving, investigating, looking up (such as via looking up in a table, database or other data structure), ascertaining, etc. Additionally, "determining" may include receiving (such as receiving information), accessing (such as accessing data in a memory), etc. Additionally, "determining" may include resolving, obtaining, selecting, choosing, establishing, and other such similar actions.

[0213] In the drawings, similar components or features may have the same reference number. In addition, various components of the same type may be distinguished by following the reference number with a dash and a second reference number to distinguish between the similar components. If only the first reference number is used in the specification, the description may apply to any of the similar components having the same first reference number, regardless of the second or other subsequent reference numbers.

[0214] The descriptions set forth herein in conjunction with the accompanying drawings describe example configurations and do not represent all examples that may be implemented or within the scope of the claims. The terms "aspect" or "example" used herein mean "used as an aspect, example, instance, or illustration," rather than "preferred" or "advantageous over other aspects." Specific implementations include specific details to provide an understanding of the described techniques. However, these techniques may be practiced without these specific details. In some cases, known structures and devices are shown in block diagram form to avoid obscuring the concepts of the described examples.

[0215] The description herein is provided to enable one of ordinary skill in the art to implement or use the present disclosure. Various modifications to the present disclosure will be apparent to one of ordinary skill in the art, and the general principles defined herein may be applied to other variations without departing from the scope of the present disclosure. Thus, the present disclosure is not limited to the examples and designs described herein, but should be granted the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A network node for wireless communication, the network node comprising: Memory; and at least one processor coupled to the memory, wherein the at least one processor is configured to: receiving a first message including information indicating an inter-band carrier aggregation configuration, the inter-band carrier aggregation configuration identifying a set of cells for communication by the network node; receiving a synchronization signal on a first cell in the set of cells via a wireless channel having a first set of channel properties; as well as Based on a first set of quasi-co-location (QCL) parameters including the first set of channel properties, one or more reference signals are received on a second cell in the set of cells, the first set of QCL parameters being used based on the synchronization signal of the first cell, the synchronization signal of the first cell being a first QCL source indicating the use of the first set of QCL parameters to receive the one or more reference signals.

2. The network node according to claim 1, wherein the at least one processor is configured to: receiving a first reference signal of the one or more reference signals on the second cell in the set of cells, wherein the synchronization signal of the first cell is the first QCL source indicating that the first reference signal is received using the first set of QCL parameters; and In addition to the one or more reference signals, a second reference signal is received on the second cell in the set of cells, wherein the first reference signal of the second cell is a second QCL source indicating that the second reference signal is received using a second set of QCL parameters.

3. The network node of claim 2, wherein the at least one processor is configured to: The first reference signal and the second reference signal of the one or more reference signals are received based on time and frequency synchronization information indicated by the synchronization signal of the first cell.

4. The network node of claim 2, wherein the first set of QCL parameters, the second set of QCL parameters, or both are associated with one or more Doppler shift parameters, one or more Doppler spread parameters, one or more average delay parameters, one or more delay spread parameters, one or more spatial receiver parameters, or any combination thereof.

5. The network node of claim 1 , wherein the at least one processor is configured to: receiving a first reference signal of the one or more reference signals on the first cell in the set of cells, wherein the synchronization signal of the first cell is the first QCL source indicating that the first reference signal is received using the first set of QCL parameters; and In addition to the one or more reference signals, a second reference signal is received on the second cell in the set of cells, wherein the first reference signal of the first cell is a second QCL source indicating that the second reference signal is received using a second set of QCL parameters.

6. The network node according to claim 5, wherein the at least one processor is configured to: The first reference signal and the second reference signal of the one or more reference signals are received on the second cell based on time and frequency synchronization information indicated by the synchronization signal of the first cell.

7. A network node according to claim 5, wherein the first set of QCL parameters, the second set of QCL parameters, or both are associated with one or more Doppler shift parameters, one or more Doppler spread parameters, one or more average delay parameters, one or more delay spread parameters, one or more spatial receiver parameters, or any combination thereof.

8. The network node of claim 1 , wherein the at least one processor is configured to: A first reference signal of the one or more reference signals is received on the second cell in the set of cells, wherein the synchronization signal of the first cell is the first QCL source indicating that the first reference signal is received using the first set of QCL parameters.

9. The network node of claim 8, wherein the at least one processor is configured to: The first reference signal of the one or more reference signals is received on the second cell based on time and frequency synchronization information indicated by the synchronization signal of the first cell.

10. The network node of claim 8, wherein the first set of QCL parameters is associated with one or more Doppler shift parameters, one or more Doppler spread parameters, one or more average delay parameters, one or more delay spread parameters, one or more spatial receiver parameters, or any combination thereof.

11. The network node of claim 1 , wherein the at least one processor is configured to: receiving a first reference signal of the one or more reference signals on a third cell in the set of cells, wherein the synchronization signal of the first cell is the first QCL source indicating that the first reference signal is received using the first set of QCL parameters; and One or more communications are received on the second cell in the set of cells, wherein the first reference signal of the third cell is a second QCL source indicating that the one or more communications are received using a second set of QCL parameters.

12. The network node of claim 11, wherein the at least one processor is configured to: The first reference signal is received on the third cell and the one or more communications are received on the second cell based on time and frequency synchronization information indicated by the synchronization signal of the first cell.

13. The network node of claim 11, wherein the first set of QCL parameters, the second set of QCL parameters, or both are associated with one or more Doppler shift parameters, one or more Doppler spread parameters, one or more average delay parameters, one or more delay spread parameters, one or more spatial receiver parameters, or any combination thereof.

14. The network node of claim 1, wherein the at least one processor is configured to: receiving a second synchronization signal and a first reference signal among the one or more reference signals on a third cell in the set of cells, wherein the second synchronization signal of the third cell is the first QCL source indicating that the first reference signal is received using the first set of QCL parameters; and One or more communications are received on the second cell in the set of cells, wherein the second synchronization signal is the first QCL source indicating the use of the first set of QCL parameters to receive the one or more communications, or wherein the first reference signal is the second QCL source indicating the use of the second set of QCL parameters to receive the one or more communications.

15. The network node of claim 14, wherein the at least one processor is configured to: receiving the one or more communications on the second cell based on time and frequency synchronization information indicated by the first synchronization signal of the first cell; and The first reference signal is received on the third cell based on the additional time and frequency synchronization information indicated by the second synchronization signal of the second cell.

16. The network node of claim 14, wherein the first set of QCL parameters, the second set of QCL parameters, or both are associated with one or more Doppler shift parameters, one or more Doppler spread parameters, one or more average delay parameters, one or more delay spread parameters, one or more spatial receiver parameters, or any combination thereof.

17. The network node of claim 1, wherein the first cell and the second cell are aligned in time according to a threshold receive timing difference.

18. The network node of claim 1, wherein the first cell and the second cell comprise a combination of a primary cell and a secondary cell, the primary cell and the secondary cell being co-located and occupying different frequency bands of the inter-band carrier aggregation configuration.

19. The network node of claim 1, wherein the one or more reference signals include a periodic channel state information reference signal (CSI-RS) for tracking or an aperiodic CSI-RS for tracking, or both.

20. A method for wireless communication at a network node, the method comprising: receiving a first message including information indicating an inter-band carrier aggregation configuration, the inter-band carrier aggregation configuration identifying a set of cells for communication by the network node; receiving a synchronization signal on a first cell in the set of cells via a wireless channel having a first set of channel properties; as well as Based on a first set of quasi-co-location (QCL) parameters including the first set of channel properties, one or more reference signals are received on a second cell in the set of cells, the first set of QCL parameters being used based on the synchronization signal of the first cell, the synchronization signal of the first cell being a first QCL source indicating the use of the first set of QCL parameters to receive the one or more reference signals.

21. The method according to claim 20, further comprising: receiving a first reference signal of the one or more reference signals on the second cell in the set of cells, wherein the synchronization signal of the first cell is the first QCL source indicating the first set of QCL parameters to be used to receive the first reference signal; as well as In addition to the one or more reference signals, a second reference signal is received on the second cell in the set of cells, wherein the first reference signal of the second cell is a second QCL source indicating that the second reference signal is received using a second set of QCL parameters.

22. The method according to claim 21, further comprising: The first reference signal and the second reference signal of the one or more reference signals are received based on time and frequency synchronization information indicated by the synchronization signal of the first cell.

23. The method of claim 21, wherein the first set of QCL parameters, the second set of QCL parameters, or both are associated with one or more Doppler shift parameters, one or more Doppler spread parameters, one or more average delay parameters, one or more delay spread parameters, one or more spatial receiver parameters, or any combination thereof.

24. The method according to claim 20, further comprising: receiving a first reference signal of the one or more reference signals on the first cell in the set of cells, wherein the synchronization signal of the first cell is the first QCL source indicating the first set of QCL parameters to be used to receive the first reference signal; as well as In addition to the one or more reference signals, a second reference signal is received on the second cell in the set of cells, wherein the first reference signal of the first cell is a second QCL source indicating that the second reference signal is received using a second set of QCL parameters.

25. The method of claim 20, further comprising: A first reference signal of the one or more reference signals is received on the second cell in the set of cells, wherein the synchronization signal of the first cell is the first QCL source indicating that the first reference signal is received using the first set of QCL parameters.

26. The method of claim 20, further comprising: receiving a first reference signal of the one or more reference signals on a third cell in the set of cells, wherein the synchronization signal of the first cell is the first QCL source indicating that the first reference signal is received using the first set of QCL parameters; as well as One or more communications are received on the second cell in the set of cells, wherein the first reference signal of the third cell is a second QCL source indicating that the one or more communications are received using a second set of QCL parameters.

27. The method of claim 20, further comprising: receiving a second synchronization signal and a first reference signal among the one or more reference signals on a third cell in the set of cells, wherein the second synchronization signal of the third cell is the first QCL source indicating that the first reference signal is received using the first set of QCL parameters; as well as One or more communications are received on the second cell in the set of cells, wherein the second synchronization signal is the first QCL source indicating the use of the first set of QCL parameters to receive the one or more communications, or wherein the first reference signal is the second QCL source indicating the use of the second set of QCL parameters to receive the one or more communications.

28. The method of claim 20, further comprising: receiving the one or more communications on the second cell based on time and frequency synchronization information indicated by the first synchronization signal of the first cell; as well as The first reference signal is received on a third cell based on the additional time and frequency synchronization information indicated by the second synchronization signal of the second cell.

29. A network node for wireless communication, the network node comprising: means for receiving a first message comprising information indicating an inter-band carrier aggregation configuration, the inter-band carrier aggregation configuration identifying a set of cells for communication by the network node; means for receiving a synchronization signal on a first cell of the set of cells via a wireless channel having a first set of channel properties; and A component for receiving one or more reference signals on a second cell in the set of cells based on a first set of quasi-co-location (QCL) parameters including the first set of channel properties, the first set of QCL parameters being used based on the synchronization signal of the first cell, the synchronization signal of the first cell being a first QCL source indicating the use of the first set of QCL parameters to receive the one or more reference signals.

30. A non-transitory computer readable medium having stored thereon code that, when executed by a network node, causes the network node to: receiving a first message including information indicating an inter-band carrier aggregation configuration, the inter-band carrier aggregation configuration identifying a set of cells for communication by the network node; receiving a synchronization signal on a first cell in the set of cells via a wireless channel having a first set of channel properties; as well as Based on a first set of quasi-co-location (QCL) parameters including the first set of channel properties, one or more reference signals are received on a second cell in the set of cells, the first set of QCL parameters being used based on the synchronization signal of the first cell, the synchronization signal of the first cell being a first QCL source indicating the use of the first set of QCL parameters to receive the one or more reference signals.

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