Dynamic multi-carrier uplink operation

Abstract

The wireless device receives one or more radio resource control (RRC) messages indicating a plurality of band pairs for uplink switching and whether each band pair of the plurality of band pairs is configured for uplink switching based on a dual uplink or a switched uplink. The wireless device may also transmit a first uplink over a first band of the first band pair and may transmit a second uplink over a second band of the first band pair. The transmission may be based on the first band pair being configured for dual uplink.

Description

[Technical field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of U.S. Provisional Patent Application No. 63 / 294,762, filed December 29, 2021, which is incorporated by reference herein in its entirety. Summary of the Invention [Means for solving the problem]

[0002] In this disclosure, various embodiments are presented as examples of how the disclosed technology may be implemented and / or how the disclosed technology may be practiced in environments and scenarios. It will be apparent to those skilled in the relevant art that various changes in form and details may be made without departing from the scope. Indeed, after reading the specification, it will be apparent to those skilled in the relevant art how to implement alternative embodiments. The present embodiments should not be limited by any of the exemplary embodiments. The embodiments of the present disclosure are described with reference to the accompanying drawings. Limitations, features, and / or elements from the disclosed exemplary embodiments may be combined to create further embodiments within the scope of the present disclosure. The figures that highlight features and advantages are shown by way of example only. The disclosed architecture is sufficiently flexible and configurable to be utilized in ways other than those shown. For example, the actions listed in any flowchart may be rearranged in some embodiments or used only optionally.

[0003] The embodiments may be configured to operate as desired. The disclosed mechanisms may be implemented when certain criteria are met, for example, in a wireless device, a base station, a wireless environment, a network, a combination of the above, etc. Exemplary criteria may be based at least in part, for example, on wireless device or network node configuration, traffic load, initial system setup, packet size, traffic characteristics, a combination of the above, etc. When one or more criteria are met, various exemplary embodiments may be applied. Thus, it may be possible to implement exemplary embodiments that selectively implement the disclosed protocols.

[0004] A base station may communicate with a mix of wireless devices. A wireless device and / or a base station may support multiple technologies and / or multiple releases of the same technology. A wireless device may have some specific capabilities depending on the category and / or capabilities of the wireless device. When the present disclosure refers to a base station communicating with multiple wireless devices, the disclosure may refer to a subset of all wireless devices in the coverage area. The disclosure may refer to multiple wireless devices of a given LTE or 5G release, for example, that include a given capability and are in a given sector of the base station. Multiple wireless devices in the present disclosure may refer to selected multiple wireless devices and / or a subset of all wireless devices in the coverage area that perform according to the disclosed methods, etc. There may be multiple base stations or multiple wireless devices in a coverage area that may not comply with the disclosed methods. For example, those wireless devices or base stations are implemented based on older releases of LTE or 5G technology. [Brief description of the drawings]

[0005] Some examples of various embodiments of the present disclosure are described herein with reference to the drawings.

[0006] [Figure 1] 1A and 1B illustrate an example mobile communication network in which embodiments of the present disclosure may be implemented.

[0007] [Diagram 2] 2A and 2B show the New Radio (NR) user plane and control plane protocol stacks, respectively.

[0008] [Diagram 3] FIG. 3 shows an example of services provided between protocol layers of the NR user plane protocol stack of FIG. 2A.

[0009] [Figure 4] Figure 4A shows an example downlink data flow through the NR user plane protocol stack of Figure 2A. Figure 4B shows an example format of a MAC subheader in a MAC PDU.

[0010] [Diagram 5] 5A and 5B show the mapping between downlink and uplink logical, transport and physical channels, respectively.

[0011] [Figure 6] FIG. 6 is an exemplary diagram illustrating RRC state transitions for a UE.

[0012] [Figure 7] FIG. 7 shows an example structure of an NR frame in which OFDM symbols are grouped.

[0013] [Figure 8] FIG. 8 shows an example configuration of slots in the time and frequency domain of an NR carrier.

[0014] [Figure 9] FIG. 9 shows an example of bandwidth adaptation using three configured BWPs for an NR carrier.

[0015] [Figure 10]Figure 10A shows a three carrier aggregation configuration with two component carriers, and Figure 10B shows an example of how the aggregation cells can be arranged into one or more PUCCH groups.

[0016] [Figure 11] Figure 11A shows an example of an SS / PBCH block structure and location, and Figure 11B shows an example of a CSI-RS mapped to the time and frequency domain.

[0017] [Figure 12] 12A and 12B show examples of three downlink and uplink beam management procedures, respectively.

[0018] [Figure 13] 13A, 13B, and 13C show a four-step contention-based random access procedure, a two-step contention-free random access procedure, and an alternative two-step random access procedure, respectively.

[0019] [Figure 14] Fig. 14A shows an example of a CORESET configuration for bandwidth portions, and Fig. 14B shows an example of CCE to REG mapping for DCI transmission on the CORESET and PDCCH processing.

[0020] [Figure 15] FIG. 15 illustrates an embodiment of a wireless device communicating with a base station.

[0021] [Figure 16] 16A, 16B, 16C, and 16D show example structures for uplink and downlink transmission.

[0022] [Figure 17]Figure 17A illustrates an example application scenario of an EN-DC deployment according to some embodiments. Figure 17B illustrates an example of an uplink operation mode of a UE in area A and area B based on the application scenario illustrated in Figure 17A according to some embodiments.

[0023] [Figure 18] Figure 18A illustrates an example application scenario of UL inter-band CA, according to some embodiments. Figure 18B illustrates an example of uplink operation modes of UEs in Area A and Area B based on the application scenario illustrated in Figure 18A, according to some embodiments.

[0024] [Figure 19] Figure 19A illustrates an example of complementary uplink coverage (SUL) according to some embodiments. Figure 19B illustrates an example application scenario of SUL according to some embodiments. Figure 19C illustrates an example of uplink operation mode of UE in area A and area B based on the applicable example shown in Figure 19B according to some embodiments.

[0025] [Figure 20] FIG. 20 illustrates an example of a wireless device transmitter antenna, according to some embodiments.

[0026] [Figure 21] Figure 21A shows an example of uplink Tx switching for a UE with 2Tx, according to some embodiments. Figure 21B shows an example of transmission options for UL Tx switching, according to some embodiments.

[0027] [Figure 22]Figure 22A illustrates an example of an uplink operation mode of a UE with uplink Tx switching in an EN-DC scenario, Figure 22B illustrates an example of an uplink operation mode of a UE with uplink Tx switching in an inter-band CA scenario, and Figure 22C illustrates an example of an uplink operation mode of a UE with uplink Tx switching in a SUL scenario, according to some embodiments.

[0028] [Figure 23] 23A and 23B show examples of UL Tx switching period positions according to some embodiments.

[0029] [Figure 24] FIG. 24 illustrates an example of UL Tx switching for a 2Tx UE according to some embodiments.

[0030] [Diagram 25] FIG. 25 illustrates an example of UL Tx switching for a 2Tx UE across more than two bands according to some embodiments.

[0031] [Figure 26] FIG. 26 illustrates an example of a UL carrier pair configured for dynamic UL Tx switching, according to some embodiments.

[0032] [Figure 27] FIG. 27 illustrates an example of signaling between a UE and a base station for carrier pair configuration in accordance with some embodiments.

[0033] [Figure 28] FIG. 28 illustrates an example of a UL carrier pair configured for dynamic UL Tx switching, according to some embodiments.

[0034] [Figure 29]FIG. 29 shows an example of dynamic UL Tx switching across four UL carriers in four different bands according to some embodiments.

[0035] [Diagram 30] FIG. 30 shows an example of dynamic UL Tx switching, according to some embodiments.

[0036] [Diagram 31] FIG. 31 shows an example of dynamic UL Tx switching according to some embodiments. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0037] As used herein, "a" and "an" and similar phrases are to be interpreted as "at least one" and "one or more". Similarly, any term ending with the suffix "(s)" should be interpreted as "at least one" and "one or more". As used herein, the term "may" should be interpreted as "may be, for example". In other words, the term "may" indicates that the phrase following the term "may" is one example of multiple preferred possibilities and may or may not be used with one or more of the various embodiments. As used herein, the terms "comprises" and "consists of" recite one or more components of a described element. The term "comprises" is interchangeable with "includes" and does not exclude unrecited components included in the described element. In contrast, "consists of" provides a complete recitation of one or more components of a described element. As used herein, the term "based on" should be interpreted as "based at least in part on" rather than, for example, "based only on". As used herein, the term "and / or" refers to any possible combination of the listed elements. For example, "A, B, and / or C" can refer to A, B, C, A and B, A and C, B and C, or A, B, and C.

[0038] If A and B are sets and every element of A is also an element of B, then A is said to be a subset of B. Only non-empty sets and subsets are considered herein. For example, possible subsets of B={cell1, cell2} are {cell1}, {cell2}, and {cell1, cell2}. The phrase "based on" (or equivalently "based at least on") indicates that the phrase following the term "based on" is one example of many suitable possibilities that may or may not be used in one or more of the various embodiments. The phrase "in response to" (or equivalently "at least in response to") indicates that the phrase following the phrase "in response to" is one example of many suitable possibilities that may or may not be used in one or more of the various embodiments. The phrase "in response to" (or equivalently "at least in response to") indicates that the phrase following the phrase "in response to" is one example of many suitable possibilities that may or may not be used in one or more of the various embodiments. The phrase "adopted / used" (or, equivalently, "adopted / used at least") indicates that the phrase following the phrase "adopted / used" is one example of many suitable possibilities that may or may not be used in one or more of the various embodiments.

[0039] The term configured may relate to the capacity of a device, whether the device is in an operational or non-operational state. Configured may refer to a particular setting of a device that affects the operational characteristics of the device, whether the device is in an operational or non-operational state. In other words, hardware, software, firmware, registers, memory values, etc. may be "configured" within a device, whether the device is in an operational or non-operational state, to provide the device with a particular characteristic. A term such as "a control message originating at a device" may mean that the control message has parameters that can be used to configure a particular characteristic in the device or to implement a particular action in the device, whether the device is in an operational or non-operational state.

[0040] In this disclosure, a parameter (or equivalently referred to as a field, or information element: IE) may contain one or more information objects, which may contain one or more other objects. For example, if parameter (IE)N contains parameter (IE)M, which contains parameter (IE)K, which contains parameter (IE)J, then, e.g., N contains K and N contains J. In an example embodiment, when one or more messages contain multiple parameters, it means that a parameter of the multiple parameters is included in at least one of the one or more messages, but need not be included in each of the one or more messages.

[0041] Many of the presented features are described as being optional through the use of "may" or through the use of parentheses. For the sake of brevity and readability, this disclosure does not explicitly describe each and every variation that may be obtained by selecting from a set of optional features. This disclosure should be construed as explicitly disclosing all such variations. For example, a system described as having three optional features may be embodied in seven ways, i.e., with only one of the three possible features, any two of the three features, or three of the three features.

[0042] Many of the elements described in the disclosed embodiments may be implemented as modules, where a module is defined as an element that performs a defined function and has a defined interface to other elements. The modules described in this disclosure may be implemented in hardware, software in combination with hardware, firmware, wetware (e.g., hardware with biological elements), or a combination thereof, which may be behaviorally equivalent. For example, a module may be implemented in software routines written in a computer language configured to run on a hardware machine (C, C++, Fortran, Java, Basic, Matlab, etc.) or Simulink, Stateflow, GNU Octave, or LabVIEW MathScript. It may also be possible to implement modules using physical hardware that incorporates discrete or programmable analog, digital, and / or quantum hardware. Examples of programmable hardware include computers, microcontrollers, microprocessors, application specific integrated circuits (ASICs), field programmable gate arrays (FPGAs), and complex programmable logic devices (CPLDs). Computers, microcontrollers, and microprocessors are programmed using languages ​​such as assembly, C, C++, etc. FPGAs, ASICs, and CPLDs are often programmed using hardware description languages ​​(HDLs) such as Verilog or VHSIC Hardware Description Language (VHDL), which configure the connections between the less functional internal hardware modules of the programmable device. To achieve a functional modular result, the above techniques are often used in combination.

[0043] 1A illustrates an example of a mobile communication network 100 in which an embodiment of the present disclosure may be implemented. The mobile communication network 100 may be, for example, a public land mobile network (PLMN) launched by a network operator. As illustrated in FIG. 1A, the mobile communication network 100 includes a core network (CN) 102, a radio access network (RAN) 104, and a wireless device 106.

[0044] The CN 102 may provide the wireless device 106 with an interface to one or more data networks (DNs), such as a public DN (e.g., the Internet), a private DN, and / or an intra-operator DN. As part of its interfacing function, the CN 102 may set up an end-to-end connection between the wireless device 106 and one or more DNs, authenticate the wireless device 106, and provide charging functionality.

[0045] The RAN 104 may connect the CN 102 to the wireless devices 106 via wireless communication over the air interface. As part of the wireless communication, the RAN 104 may provide scheduling, radio resource management, and retransmission protocols. The communication direction from the RAN 104 to the wireless devices 106 over the air interface is known as the downlink, and the communication direction from the wireless devices 106 to the RAN 104 over the air interface is known as the uplink. Downlink transmissions may be separated from uplink transmissions using frequency division duplexing (FDD), time division duplexing (TDD), and / or some combination of the two duplexing techniques.

[0046] The term wireless device may be used throughout this disclosure to refer to and encompass any mobile or fixed (non-portable) device for which wireless communication is required or available. For example, a wireless device may be a phone, a smartphone, a tablet, a computer, a laptop, a sensor, a meter, a wearable device, an Internet of Things (IoT) device, a vehicular roadside unit (RSU), a relay node, an automobile, and / or any combination thereof. The term wireless device encompasses other terms, including user equipment (UE), user terminal (UT), access terminal (AT), mobile station, handset, wireless transmit / receive unit (WTRU), and / or wireless communication device.

[0047] The RAN 104 may include one or more base stations (not shown). The term base station may be used throughout this disclosure to refer to and encompass a Node B (associated with UMTS and / or 3G standards), an evolved Node B (eNB, associated with E-UTRA and / or 4G standards), a remote radio head (RRH), a baseband processing unit coupled to one or more RRHs, a repeater or relay node used to extend the coverage area of ​​a donor node, a next generation evolved Node B (ng-eNB), a generation Node B (gNB, associated with NR and / or 5G standards), an access point (AP, e.g., associated with WiFi or other suitable wireless communication standard), and / or any combination thereof. A base station may include at least one gNB central unit (gNB-CU) and at least one gNB distributed unit (gNB-DU).

[0048] The base stations included in the RAN 104 may include one or more sets of antennas for communicating over the air interface with the wireless devices 106. For example, one or more of the base stations may include three sets of antennas for controlling three cells (or sectors) respectively. The size of a cell may be determined by the range over which a receiver (e.g., a base station receiver) can successfully receive transmissions from a transmitter (e.g., a wireless device transmitter) operating in the cell. Together, the cells of the base stations may provide wireless coverage to the wireless devices 106 over a wide geographic area to support wireless device mobility.

[0049] In addition to three sector sites, other implementations of base stations are possible. For example, one or more of the base stations of the RAN 104 may be implemented as a sector site having more or less than three sectors. One or more of the base stations of the RAN 104 may be implemented as an access point, as a base band processing unit coupled to multiple remote radio heads (RRHs), and / or as a repeater or relay node used to extend the coverage area of ​​a donor node. The base band processing unit coupled to the RRHs may be part of a centralized or cloud RAN architecture, where the base band processing unit may be centralized or virtualized within a pool of base band processing units. The repeater node may amplify and rebroadcast the wireless signal received from the donor node. The relay node may perform the same / similar functions as the repeater node, but may decode the wireless signal received from the donor node and remove noise before amplifying and rebroadcasting the wireless signal.

[0050] The RAN 104 may be deployed as a homogeneous network of macrocell base stations having similar antenna patterns and similar high-level transmit power. The RAN 104 may be deployed as a heterogeneous network. In a heterogeneous network, small cell base stations may be used to provide small coverage areas, such as coverage areas that overlap with the relatively large coverage areas provided by macrocell base stations. The small coverage areas may be provided in areas of high data traffic (or so-called "hot spots") or areas where macrocell coverage is weak. Examples of small cell base stations include, in order of decreasing coverage area, microcell base stations, picocell base stations, and femtocell or home base stations.

[0051] The Third Generation Partnership Project (3GPP®) was formed in 1998 to provide global standardization of specifications for mobile communication networks similar to the mobile communication network 100 of FIG. 1A. To date, 3GPP® has produced specifications for three generations of mobile networks: a third generation (3G) network known as Universal Mobile Telecommunications System (UMTS), a fourth generation (4G) network known as Long Term Evolution (LTE), and a fifth generation (5G) network known as 5G System (5GS). Embodiments of the present disclosure are described with reference to a RAN of a 3GPP® 5G network, referred to as Next Generation RAN (NG-RAN). The embodiments may be applicable to the RAN of other mobile communication networks, such as the RAN 104 of FIG. 1A, RANs of earlier 3G and 4G networks, and future networks yet to be specified (e.g., a 3GPP® 6G network). NG-RAN implements the 5G radio access technology known as New Radio (NR), and may be provisioned to implement other radio access technologies, including 4G radio access technologies or non-3GPP radio access technologies.

[0052] 1B illustrates another exemplary mobile communication network 150 in which embodiments of the present disclosure may be implemented. The mobile communication network 150 may be, for example, a PLMN launched by a network operator. As illustrated in FIG. 1B, the mobile communication network 150 includes a 5G core network (5G-CN) 152, an NG-RAN 154, and a UE 156A and a UE 156B (collectively, UE 156). These components may be implemented and operate in the same or similar manner as the corresponding components described with respect to FIG. 1A.

[0053] 5G-CN 152 provides UE 156 with an interface to one or more DNs, such as a public DN (e.g., Internet), a private DN, and / or an intra-operator DN. As part of the interface function, 5G-CN 152 may set up an end-to-end connection between UE 156 and one or more DNs, authenticate UE 156, and provide charging functions. Compared to the CNs of 3GPP 4G networks, the base of 5G-CN 152 may be a service-based architecture. This means that the architecture of the nodes constituting 5G-CN 152 may be defined as a network function that provides services via interfaces to other network functions. The network functions of 5G-CN 152 may be implemented in several ways: as network elements on dedicated or shared hardware, as software instances running on dedicated or shared hardware, or as virtualized functions instantiated on a platform (e.g., a cloud-based platform).

[0054] As shown in FIG. 1B, the 5G-CN 152 includes an Access and Mobility Management Function (AMF) 158A and a User Plane Function (UPF) 158B, shown as one component AMF / UPF 158 in FIG. 1B for ease of explanation. The UPF 158B may act as a gateway between the NG-RAN 154 and one or more DNs. The UPF 158B may perform functions such as packet routing and forwarding, packet inspection and enforcement of user plane policy rules, traffic utilization reporting, uplink classification to support routing of traffic flows to one or more DNs, quality of service (QoS) processing for the user plane (e.g., packet filtering, gating, uplink / downlink rate enforcement, and uplink traffic validation), downlink packet buffering, and downlink data notification triggers. The UPF 158B may act as an anchor point for intra / inter radio access technology (RAT) mobility, an external protocol (or packet) data unit (PDU) session point interconnected to one or more DNs, and / or a branching point to support multi-homed PDU sessions. The UE 156 may be configured to receive services via a PDU session, which is a logical connection between the UE and the DN.

[0055] The AMF 158A may perform functions such as termination of Non-Access Stratum (NAS) signaling, NAS signaling security, Access Stratum (AS) security control, inter-CN node signaling for mobility between 3GPP® access networks, idle mode UE reachability (e.g., control and execution of paging retransmissions), registration area management, intra-system and inter-system mobility support, access authentication, access authorization including checking roaming rights, mobility management control (subscription and policy), support for network slicing, and / or selection of a Session Management Function (SMF). NAS may refer to a function operating between the CN and the UE, and AS may refer to a function operating between the UE and the RAN.

[0056] 5G-CN 152 may include one or more additional network functions not shown in FIG. 1B for clarity. For example, 5G-CN 152 may include one or more of a Session Management Function (SMF), an NR Repository Function (NRF), a Policy Control Function (PCF), a Network Exposure Function (NEF), a Unified Data Management (UDM), an Application Function (AF), and / or an Authentication Server Function (AUSF).

[0057] The NG-RAN 154 may connect the 5G-CN 152 to the UE 156 via wireless communication over the air interface. The NG-RAN 154 may include one or more gNBs (collectively gNB 160), illustrated as gNB 160A and gNB 160B, and / or one or more ng-eNBs (collectively ng-eNB 162), illustrated as ng-eNB 162A and ng-eNB 162B. The gNBs 160 and ng-eNB 162 may be more generally referred to as base stations. The gNBs 160 and ng-eNB 162 may include one or more sets of antennas for communicating with the UE 156 over the air interface. For example, one or more of the gNBs 160 and / or one or more of the ng-eNBs 162 may include three sets of antennas for controlling three cells (or sectors), respectively. Together, the gNB160 and ng-eNB162 cells may provide radio coverage to the UE156 over a wide geographic area to support UE mobility.

[0058] As shown in FIG. 1B, the gNB 160 and / or the ng-eNB 162 may be connected to the 5G-CN 152 by an NG interface and to other base stations by an Xn interface. The NG and Xn interfaces may be established using direct physical connections and / or indirect connections over an underlying transport network, such as an Internet Protocol (IP) transport network. The gNB 160 and / or the ng-eNB 162 may be connected to the UE 156 by a Uu interface. For example, as shown in FIG. 1B, the gNB 160A may be connected to the UE 156A by a Uu interface. The NG, Xn, and Uu interfaces are associated with protocol stacks. The protocol stacks associated with the interfaces may be used by the network elements of FIG. 1B to exchange data and signaling messages and may include two planes, a user plane and a control plane. The user plane may process data of interest to a user. The control plane may process signaling messages of interest to the network elements.

[0059] The gNB 160 and / or ng-eNB 162 may be connected to one or more AMF / UPF functions of the 5G-CN 152, such as the AMF / UPF 158, by one or more NG interfaces. For example, the gNB 160A may be connected to the UPF 158B of the AMF / UPF 158 by an NG-User Plane (NG-U) interface. The NG-U interface may provide for the provision of user plane PDUs between the gNB 160A and the UPF 158B (e.g., non-guaranteed delivery). The gNB 160A may be connected to the AMF 158A using an NG Control Plane (NG-C) interface. The NG-C interface may provide, for example, NG interface management, UE context management, UE mobility management, transport of NAS messages, paging, PDU session management, and configuration transfer and / or alert message transmission.

[0060] The gNB 160 may provide NR user plane and control plane protocol terminations towards the UE 156 on the Uu interface. For example, the gNB 160A may provide NR user plane and control plane protocol terminations towards the UE 156A on the Uu interface associated with a first protocol stack. The ng-eNB 162 may provide Evolved UMTS Terrestrial Radio Access (E-UTRA) user plane and control plane protocol terminations towards the UE 156 on the Uu interface, where E-UTRA refers to a 3GPP 4G radio access technology. For example, the ng-eNB 162B may provide E-UTRA user plane and control plane protocol terminations towards the UE 156B on the Uu interface associated with a second protocol stack.

[0061] The 5G-CN 152 has been described as being configured to handle NR and 4G radio access. Those skilled in the art will appreciate that it may be possible for the NR to connect to a 4G core network in a mode known as "non-standalone operation." In non-standalone operation, the 4G core network is used to provide (or at least support) control plane functions (e.g., initial access, mobility, and paging). Although only one AMF / UPF 158 is shown in FIG. 1B, one gNB or ng-eNB may be connected to multiple AMF / UPF nodes to provide redundancy and / or load sharing across multiple AMF / UPF nodes.

[0062] As discussed in Figure 1B, interfaces between network elements (e.g., Uu, Xn, and NG interfaces) may be associated with protocol stacks that the network elements use to exchange data and signaling messages. The protocol stacks may include two planes: a user plane and a control plane. The user plane may handle data of interest to a user, and the control plane may handle signaling messages of interest to the network elements.

[0063] Figures 2A and 2B show examples of NR user plane and NR control plane protocol stacks, respectively, for the Uu interface between a UE 210 and a gNB 220. The protocol stacks shown in Figures 2A and 2B may be the same or similar to those used for the Uu interface between a UE 156A and a gNB 160A shown in Figure 1B, for example.

[0064] 2A shows an NR user plane protocol stack including five layers implemented in the UE 210 and the gNB 220. At the bottom of the protocol stack, a physical layer (PHY) 211 and 221 may provide transport services to the upper layers of the protocol stack and may correspond to layer 1 of the Open Systems Interconnection (OSI) model. The next four protocols above the PHYs 211 and 221 include a media access control layer (MAC) 212 and 222, a radio link control layer (RLC) 213 and 223, a packet data convergence protocol layer (PDCP) 214 and 224, and a service data application protocol layer (SDAP) 215 and 225. Together, these four protocols may constitute layer 2 or the data link layer of the OSI model.

[0065] FIG. 3 illustrates an example of services provided between protocol layers of the NR user plane protocol stack. Starting from the top of FIG. 2A and FIG. 3, the SDAPs 215 and 225 may perform QoS flow processing. The UE 210 may receive services via a PDU session, which may be a logical connection between the UE 210 and the DN. The PDU session may have one or more QoS flows. The UPF (e.g., UPF 158B) of the CN may map IP packets to one or more QoS flows of the PDU session based on the QoS requirements (e.g., in terms of delay, data rate, and / or error rate). The SDAPs 215 and 225 may perform mapping / de-mapping between one or more QoS flows and one or more data radio bearers. The mapping / de-mapping between the QoS flows and the data radio bearers may be determined by the SDAP 225 at the gNB 220. The SDAP 215 at the UE 210 may be informed of the mapping between the QoS flows and the data radio bearers via reflected mapping or control signaling received from the gNB 220. For reflective mapping, the SDAP 225 at the gNB 220 may mark the downlink packets with a QoS flow indicator (QFI) that may be observed by the SDAP 215 at the UE 210 to determine mapping / demapping between QoS flows and data radio bearers.

[0066] The PDCPs 214 and 224 may perform header compression / decompression to reduce the amount of data that needs to be transmitted over the air interface, encryption / decryption to prevent unauthorized decryption of data transmitted over the air interface, and integrity protection (to ensure that control messages originate from the intended source. The PDCPs 214 and 224 may perform retransmission of undelivered packets, in-sequence delivery and reordering of packets, and elimination of duplicate received packets, for intra-gNB handover, for example. The PDCPs 214 and 224 may perform packet duplication to improve the likelihood of a packet being received and to eliminate any duplicate packets at the receiver. Packet duplication may be useful for services that require high reliability.

[0067] Although not shown in FIG. 3, the PDCPs 214 and 224 may perform mapping / demapping between split radio bearers and RLC channels in a dual connectivity scenario. Dual connectivity is a technique that allows a UE to connect to two cells, or more generally, two cell groups, a master cell group (MCG) and a secondary cell group (SCG). A split bearer is when a single radio bearer, such as one of the radio bearers provided by the PDCPs 214 and 224 as a service to the SDAPs 215 and 225, is handled by a cell group in dual connectivity. The PDCPs 214 and 224 may map / demap the split radio bearer between the RLC channels belonging to the cell group.

[0068] The RLCs 213 and 223 may perform segmentation, retransmission through automatic repeat request (ARQ), and removal of duplicate data units received from the MACs 212 and 222, respectively. The RLCs 213 and 223 may support three transmission modes: transparent mode (TM), unacknowledged mode (UM), and acknowledged mode (AM). Based on the transmission mode in which the RLC is operating, the RLC may perform one or more of the indicated functions. This RLC configuration may be per logical channel independent of numerology and / or transmission time interval (TTI) duration. As shown in FIG. 3, the RLCs 213 and 223 may provide RLC channels as services to the PDCPs 214 and 224, respectively.

[0069] The MACs 212 and 222 may perform multiplexing / demultiplexing of logical channels and / or mapping between logical channels and transport channels. Multiplexing / demultiplexing may include multiplexing / demultiplexing of data units belonging to one or more logical channels to / from a transport block (TB) delivered to / from the PHYs 211 and 221. The MAC 222 may be configured to perform scheduling, scheduling information reporting, and prioritization between UEs by dynamic scheduling. Scheduling may be performed at the gNB 220 (at the MAC 222) for downlink and uplink. The MACs 212 and 222 may be configured to perform error correction, prioritization between logical channels of the UE 210 by logical channel prioritization, and / or padding through hybrid automatic repeat request (HARQ) (e.g., one HARQ entity per carrier in case of carrier aggregation (CA)). The MACs 212 and 222 may support one or more numerologies and / or transmission timings. In an embodiment, mapping restrictions on logical channel prioritization may control which numerology and / or transmission timing a logical channel may use. As shown in FIG. 3, MACs 212 and 222 may provide logical channels to RLCs 213 and 223 as services.

[0070] The PHYs 211 and 221 may perform mapping of transport channels to physical channels and digital and analog signal processing functions to transmit and receive information over the air interface. These digital and analog signal processing functions may include, for example, coding / decoding and modulation / demodulation. The PHYs 211 and 221 may perform multi-antenna mapping. As shown in FIG. 3, the PHYs 211 and 221 may provide one or more transport channels to the MACs 212 and 222 as a service.

[0071] 4A illustrates an example downlink data flow through the NR user plane protocol stack. FIG. 4A illustrates the downlink data flow of three IP packets (n, n+1, and m) through the NR user plane protocol stack, generating two TBs at the gNB 220. The uplink data flow through the NR user plane protocol stack may be similar to the downlink data flow illustrated in FIG. 4A.

[0072] The downlink data flow in FIG. 4A starts when the SDAP 225 receives three IP packets from one or more QoS flows and maps the three packets to radio bearers. In FIG. 4A, the SDAP 225 maps IP packets n and n+1 to the first radio bearer 402 and maps IP packet m to the second radio bearer 404. An SDAP header (labeled "H" in FIG. 4A) is added to the IP packets. Data units from / to the higher protocol layer are referred to as service data units (SDUs) of the lower protocol layer, and data units to / from the lower protocol layer are referred to as protocol data units (PDUs) of the higher protocol layer. As shown in FIG. 4A, the data units from the SDAP 225 are the SDUs of the lower protocol layer PDCP 224 and the PDUs of the SDAP 225.

[0073] The remaining protocol layers in FIG. 4A may perform the relevant functions (e.g., with respect to FIG. 3), add corresponding headers, and forward the respective outputs to the next lower layer. For example, PDCP 224 may perform IP header compression and encryption and forward its output to RLC 223. RLC 223 may optionally perform segmentation (e.g., as shown for IP packet m in FIG. 4A) and forward its output to MAC 222. MAC 222 may multiplex several RLC PDUs and attach MAC subheaders to the RLC PDUs to form a transport block. In NR, the MAC subheader may be distributed throughout the MAC PDU as shown in FIG. 4A. In LTE, the MAC subheader may be placed entirely at the beginning of the MAC PDU. The NR MAC PDU structure may reduce processing time and associated delays because the MAC PDU subheaders may be calculated before the complete MAC PDU is assembled.

[0074] 4B shows an example format of a MAC subheader in a MAC PDU. The MAC subheader includes an SDU length field to indicate the length (e.g., in bytes) of the MAC SDU that the MAC subheader corresponds to, a logical channel identifier (LCID) field to identify the logical channel on which the MAC SDU started to assist in the demultiplexing process, a flag (F) to indicate the size of the SDU length field, and a reserved bit (R) field for future use.

[0075] FIG. 4B further illustrates MAC Control Elements (CEs) inserted into the MAC PDU by a MAC, such as MAC 223 or MAC 222. For example, FIG. 4B illustrates two MAC CEs inserted into the MAC PDU. MAC CEs may be inserted at the start of the MAC PDU for downlink transmission (as shown in FIG. 4B) and at the end of the MAC PDU for uplink transmission. MAC CEs may be used for in-band control signaling. Examples of MAC CEs include scheduling-related MAC CEs, such as buffer status reports and power headroom reports, activation / deactivation MAC CEs, such as for PDCP duplicate detection activation / deactivation, channel state information (CSI) reports, sounding reference signal (SRS) transmissions, and pre-configured components, discontinuous reception (DRX)-related MAC CEs, timing advancement MAC CEs, and random access-related MAC CEs. MAC CEs may be preceded by a MAC subheader of a format similar to that described for the MAC SDU and may be identified with a reserved value in the LCID field indicating the type of control information included in the MAC CE.

[0076] Before describing the NR control plane protocol stack, we first describe logical, transport, and physical channels and the mapping between channel types, one or more of which may be used to perform functions related to the NR control plane protocol stack, as described below.

[0077] 5A and 5B show the mapping between logical, transport, and physical channels for the downlink and uplink, respectively. Information is passed through channels between the RLC, MAC, and PHY of the NR protocol stack. Logical channels may be used between the RLC and MAC and may be classified as control channels, which carry control and configuration information in the NR control plane, or as traffic channels, which carry data in the NR user plane. Logical channels may be classified as dedicated logical channels, which are dedicated to a particular UE, or as common logical channels, which may be used by two or more UEs. Logical channels may also be defined by the type of information they carry. The set of logical channels defined by NR includes, for example, - a Paging Control Channel (PCCH) for carrying paging messages used to page UEs whose location is unknown to the network at the cell level; - a Broadcast Control Channel (BCCH) for carrying system information messages in the form of a Master Information Block (MIB) and several System Information Blocks (SIBs), which may be used by UEs to obtain information about how the cell is configured and how to operate within the cell; - a Common Control Channel (CCCH) for carrying control messages along with random access; - a Dedicated Control Channel (DCCH) for carrying control messages to and from a specific UE for configuring the UE; - A Dedicated Traffic Channel (DTCH) for carrying user data to and from a specific UE.

[0078] Transport channels are used between the MAC and PHY layers and may be defined by how the information they carry is transmitted over the air interface. The set of transport channels defined by NR includes, for example: - a paging channel (PCH) for carrying paging messages originating from the PCCH; - a Broadcast Channel (BCH) for carrying the MIB from the BCCH; - a Downlink Shared Channel (DL-SCH) for carrying downlink data and signaling messages, including SIBs from the BCCH; - an uplink shared channel (UL-SCH) for carrying uplink data and signaling messages; - A Random Access Channel (RACH) that allows a UE to contact the network without prior scheduling.

[0079] The PHY may pass information between processing levels of the PHY using physical channels. A physical channel may have an associated set of time-frequency resources for carrying information for one or more transport channels. The PHY may generate control information to support the lower level operation of the PHY and provide control information to the lower levels of the PHY via physical control channels known as L1 / L2 control channels. The set of physical channels and physical control channels defined by NR may include, for example: - a Physical Broadcast Channel (PBCH) to carry the MIB from the BCH; - a Physical Downlink Shared Channel (PDSCH) for carrying downlink data and signaling messages from the DL-SCH and paging messages from the PCH; - a Physical Downlink Control Channel (PDCCH) for carrying Downlink Control Information (DCI), which may include downlink scheduling commands, uplink scheduling grants, and uplink power control commands; - a Physical Uplink Shared Channel (PUSCH) for carrying uplink data and signaling messages from the UL-SCH and, in some examples, Uplink Control Information (UCI), as described below; - a physical uplink control channel (PUCCH) for carrying UCI, which may include a HARQ acknowledgement, a channel quality indicator (CQI), a precoding matrix indicator (PMI), a rank indicator (RI), and a scheduling request (SR); - A Physical Random Access Channel (PRACH) for random access.

[0080] Similar to the physical control channel, the physical layer generates physical signals to support the low-level operations of the physical layer. As shown in Figures 5A and 5B, the physical layer signals defined by NR include the Primary Synchronization Signal (PSS), the Secondary Synchronization Signal (SSS), the Channel State Information Reference Signal (CSI-RS), the Demodulation Reference Signal (DMRS), the Sounding Reference Signal (SRS), and the Phase Tracking Reference Signal (PT-RS). These physical layer signals are described in more detail below.

[0081] FIG. 2B shows an example NR control plane protocol stack. In FIG. 2B, the NR control plane protocol stack may use the first four protocol layers that are the same / similar to the example NR user plane protocol stack. These four protocol layers include PHY 211 and 221, MAC 212 and 222, RLC 213 and 223, and PDCP 214 and 224. Instead of having SDAP 215 and 225 at the top of the stack as in the NR user plane protocol stack, the NR control plane stack has radio resource control (RRC) 216 and 226, and NAS protocols 217 and 237 at the top of the NR control plane protocol stack.

[0082] The NAS protocols 217 and 237 may provide control plane functions between the UE 210 and the AMF 230 (e.g., AMF 158A), or more generally, between the UE 210 and the CN. The NAS protocols 217 and 237 may provide control plane functions between the UE 210 and the AMF 230 via signaling messages referred to as NAS messages. There is no direct path between the UE 210 and the AMF 230 over which NAS messages can be transported. NAS messages may be transported using ASs of the Uu and NG interfaces. The NAS protocols 217 and 237 may provide control plane functions such as authentication, security, connection setup, mobility management, and session management.

[0083] The RRC 216 and 226 may provide a control plane function between the UE 210 and the gNB 220, or more generally, between the UE 210 and the RAN. The RRC 216 and 226 may provide a control plane function between the UE 210 and the gNB 220 via signaling messages referred to as RRC messages. The RRC messages may be transmitted between the UE 210 and the RAN using signaling radio bearers and the same / similar PDCP, RLC, MAC, and PHY protocol layers. The MAC may multiplex the control plane and user plane data into the same transport block (TB). The RRCs 216 and 226 may provide control plane functions such as broadcasting system information related to the AS and the NAS, paging initiated by the CN or the RAN, establishment, maintenance, and release of an RRC connection between the UE 210 and the RAN, security functions including key management, establishment, configuration, maintenance, and release of signaling and data radio bearers, mobility functions, QoS management functions, control of UE measurement reporting and reporting, radio link failure (RLF) detection and recovery, and / or NAS message forwarding. As part of establishing an RRC connection, the RRCs 216 and 226 may establish an RRC context, which may involve setting parameters for communications between the UE 210 and the RAN.

[0084] FIG. 6 is an example diagram illustrating RRC state transitions of a UE. The UE may be the same as or similar to the wireless device 106 shown in FIG. 1A, the UE 210 shown in FIG. 2A and FIG. 2B, or any other wireless device described in this disclosure. As shown in FIG. 6, the UE may be in at least one of three RRC states: RRC connected 602 (e.g., RRC_CONNECTED), RRC idle 604 (e.g., RRC_IDLE), and RRC inactive 606 (e.g., RRC_INACTIVE).

[0085] In the RRC connection 602, the UE has an established RRC context and may have at least one RRC connection with a base station. The base station may be similar to one of the base stations included in the RAN 104 shown in FIG. 1A, one of the gNB 160 or ng-eNB 162 shown in FIG. 1B, the gNB 220 shown in FIG. 2A and FIG. 2B, or any other base station described in this disclosure. The base station to which the UE is connected may have an RRC context for the UE. The RRC context, referred to as the UE context, may include parameters for communication between the UE and the base station. These parameters may include, for example, one or more AS contexts, one or more radio link configuration parameters, bearer configuration information (e.g., related to data radio bearers, signaling radio bearers, logical channels, QoS flows, and / or PDU sessions), security information, and / or PHY, MAC, RLC, PDCP, and / or SDAP layer configuration information. In the RRC connection 602, the mobility of the UE may be managed by the RAN (e.g., the RAN 104 or the NG-RAN 154). The UE may measure signal levels (e.g., reference signal levels) from the serving cell and neighboring cells and report these measurements to the base station currently serving the UE. The UE's serving base station may request a handover to a cell of one of the neighboring base stations based on the reported measurements. The RRC state may transition from RRC Connected 602 to RRC Idle 604 via a Connection Release procedure 608 or to RRC Inactive 606 via a Connection Deactivation procedure 610.

[0086] In RRC Idle 604, no RRC context may be established for the UE. In RRC Idle 604, the UE may not have an RRC connection with a base station. While in RRC Idle 604, the UE may be in a sleep state most of the time (e.g., to conserve battery power). The UE may wake up periodically (e.g., once every discontinuous reception cycle) to monitor for paging messages from the RAN. UE mobility may be managed by the UE through a procedure known as cell reselection. The RRC state may transition from RRC Idle 604 to RRC Connected 602 via a connection establishment procedure 612, which may involve a random access procedure as discussed in more detail below.

[0087] In RRC Inactive 606, previously established RRC context is maintained in the UE and base station. This allows for faster transition to RRC Connection 602 with reduced signaling overhead compared to transition from RRC Idle 604 to RRC Connection 602. In RRC Inactive 606, the UE is in a sleep state and UE mobility may be managed by the UE through cell reselection. The RRC state may transition from RRC Inactive 606 to RRC Connection 602 by a Connection Resume procedure 614 or to RRC Idle 604 via a Connection Release procedure 616 that is the same as or similar to the Connection Release procedure 608.

[0088] The RRC states may be associated with mobility management mechanisms. In RRC Idle 604 and RRC Inactive 606, mobility is managed by the UE through cell reselection. The purpose of mobility management in RRC Idle 604 and RRC Inactive 606 is to allow the network to inform the UE of events via paging messages without broadcasting the paging messages throughout the entire mobile communication network. The mobility management mechanisms used in RRC Idle 604 and RRC Inactive 606 may allow the network to track the UE on a cell group level, so that paging messages may be broadcast on cells of the cell group in which the UE is currently located instead of the entire mobile communication network. The mobility management mechanisms in RRC Idle 604 and RRC Inactive 606 track the UE on a cell group level. They may do so using different granularity of grouping. For example, there may be three levels of granularity of cell grouping: individual cells, cells within a RAN area identified by a RAN Area Identifier (RAI), and cells within a group of RAN areas referred to as a tracking area and identified by a Tracking Area Identifier (TAI).

[0089] The tracking area may be used to track the UE at the CN level. The CN (e.g., CN 102 or 5G-CN 152) may provide the UE with a list of TAIs associated with the UE registration area. If the UE moves through cell reselection to a cell associated with a TAI that is not included in the list of TAIs associated with the UE registration area, the UE may perform a registration update with the CN to enable the CN to update the UE's location and provide the UE with a new UE registration area.

[0090] The RAN area may be used to track the UE at the RAN level. For a UE in RRC inactive 606 state, a RAN notification area may be assigned to the UE. The RAN notification area may include one or more cell identities, a list of RAIs, or a list of TAIs. In an embodiment, a base station may belong to one or more RAN notification areas. In an embodiment, a cell may belong to one or more RAN notification areas. If the UE moves through cell reselection to a cell that is not included in the RAN notification area assigned to the UE, the UE may perform a notification area update with the RAN to update the RAN notification area of ​​the UE.

[0091] A base station that stores the RRC context for the UE or the last serving base station for the UE may be referred to as an anchor base station. The anchor base station may maintain the RRC context for the UE at least for a period of time that the UE remains in the RAN notification area of ​​the anchor base station and / or for a period of time that the UE remains in RRC inactive 606.

[0092] A gNB, such as gNB 160 in FIG. 1B, may be divided into two parts: a central unit (gNB-CU) and one or more distributed units (gNB-DU). The gNB-CU may be coupled to one or more gNB-DUs using an F1 interface. The gNB-CU may include RRC, PDCP, and SDAP. The gNB-DU may include RLC, MAC, and PHY.

[0093] In NR, physical signals and physical channels (discussed with respect to FIG. 5A and FIG. 5B) may be mapped onto orthogonal frequency division multiplexing (OFDM) symbols. OFDM is a multicarrier communication scheme that transmits data on F orthogonal subcarriers (or tones). Before transmission, the data may be mapped to a series of complex symbols (e.g., M-quadrature amplitude modulation (M-QAM) or M-phase shift keying (M-PSK) symbols), referred to as source symbols, which are split into F parallel symbol streams. The F parallel symbol streams may be treated as if they were in the frequency domain and used as input to an inverse fast Fourier transform (IFFT) block, which converts them to the time domain. The IFFT block may take F source symbols, one at a time, from each of the F parallel symbol streams and use each source symbol to modulate the amplitude and phase of one of the F sinusoidal basis functions corresponding to the F orthogonal subcarriers. The output of the IFFT block may be F time domain samples representing a sum of the F orthogonal subcarriers. The F time domain samples may form a single OFDM symbol. After some processing (e.g., adding a cyclic prefix) and upconversion, the OFDM symbols provided by the IFFT block may be transmitted over the air interface at a carrier frequency. The F parallel symbol streams may be mixed using an FFT block before being processed by the IFFT block. This processing produces a Discrete Fourier Transform (DFT) precoded OFDM symbol, which can be used by UEs in the uplink to reduce the peak-to-average power ratio (PAPR). Inverse processing may be performed on the OFDM symbols at the receiver using an FFT block to recover the data mapped to the source symbols.

[0094] FIG. 7 illustrates an example configuration of an NR frame in which OFDM symbols are grouped. An NR frame may be identified by a system frame number (SFN). The SFN may repeat at a period of 1024 frames. As illustrated, an NR frame may be 10 milliseconds (ms) in duration and may include 10 subframes, each of which is 1 ms in duration. The subframes may be divided into slots, each of which includes, for example, 14 OFDM symbols per slot.

[0095] The duration of a slot may depend on the numerology used for the OFDM symbol of the slot. In NR, flexible numerologies are supported to accommodate different cell deployments (e.g., cells with carrier frequencies less than 1 GHz up to cells with carrier frequencies in the mm-wave range). Numerologies may be defined in terms of subcarrier spacing and cyclic prefix duration. For numerology in NR, subcarrier spacing may be scaled up by powers of two from a baseline subcarrier spacing of 15 kHz, and cyclic prefix duration may be scaled down by powers of two from a baseline cyclic prefix duration of 4.7 μs. For example, NR defines numerologies with the following subcarrier spacing / cyclic prefix duration combinations: 15 kHz / 4.7 μs, 30 kHz / 2.3 μs, 60 kHz / 1.2 μs, 120 kHz / 0.59 μs, and 240 kHz / 0.29 μs.

[0096] A slot may have a fixed number of OFDM symbols (e.g., 14 OFDM symbols). Numerologies with higher subcarrier spacing have shorter slot durations and correspondingly more slots per subframe. Figure 7 illustrates this numerology-dependent slot duration and slot-per-subframe transmission structure (for ease of illustration, a numerology with 240 kHz subcarrier spacing is not shown in Figure 7). Subframes in NR may be used as numerology-independent time references, while slots may be used as units by which uplink and downlink transmissions are scheduled. To support low latency, scheduling in NR is decoupled from the slot duration and may start at any OFDM symbol and continue for as many symbols as necessary for transmission. These partial slot transmissions may be referred to as minislot or subslot transmissions.

[0097] FIG. 8 shows an example configuration of slots in the time and frequency domains of an NR carrier. A slot includes resource elements (REs) and resource blocks (RBs). An RE is the smallest physical resource in NR. An RE spans one OFDM symbol in the time domain by one subcarrier in the frequency domain as shown in FIG. 8. An RB spans 12 consecutive REs in the frequency domain as shown in FIG. 8. An NR carrier may be limited to a width of 275 RBs or 275×12=3300 subcarriers. Such limitations, if used, may limit an NR carrier to 50, 100, 200, and 400 MHz for subcarrier spacings of 15, 30, 60, and 120 kHz, respectively, and the 400 MHz bandwidth may be set based on the 400 MHz per carrier bandwidth limit.

[0098] Figure 8 shows a single numerology used across the entire bandwidth of an NR carrier. In other example configurations, multiple numerologies may be supported on the same carrier.

[0099] NR may support a wide range of carrier bandwidths (e.g., up to 400 MHz with 120 kHz subcarrier spacing). Not all UEs may be able to receive the full carrier bandwidth (e.g., hardware limitations, etc.). Also, receiving the full carrier bandwidth may be prohibitive from a UE power consumption perspective. In an embodiment, to reduce power consumption and / or for other purposes, the UE may adapt the size of its reception bandwidth based on the amount of traffic the UE is scheduled to receive. This is referred to as bandwidth adaptation.

[0100] NR defines a bandwidth portion (BWP) to support UEs that cannot receive the entire carrier bandwidth and to support bandwidth adaptation. In one embodiment, a BWP may be defined by a subset of contiguous RBs on a carrier. A UE may be configured (e.g., via the RRC layer) with one or more downlink BWPs and one or more uplink BWPs per serving cell (e.g., up to four downlink BWPs and up to four uplink BWPs per serving cell). At a given time, one or more of the BWPs configured for a serving cell may be active. These one or more BWPs may be referred to as the active BWP of the serving cell. When a serving cell is configured with a secondary uplink carrier, the serving cell may have one or more first active BWPs on the uplink carrier and one or more second active BWPs on the secondary uplink carrier.

[0101] For an unpaired spectrum, a downlink BWP from a set of configured downlink BWPs may be linked with an uplink BWP from a set of configured uplink BWPs if the downlink BWP index of the downlink BWP and the uplink BWP index of the uplink BWP are the same. For an unpaired spectrum, the UE may expect the center frequency of the downlink BWP to be the same as the center frequency of the uplink BWP.

[0102] For a downlink BWP in a set of configured downlink BWPs on a primary cell (PCell), the base station may configure the UE with one or more control resource sets (CORESETs) for at least one search space. A search space is a set of locations in the time and frequency domain where the UE can find control information. The search space may be a UE-specific search space or a common search space (potentially usable by multiple UEs). For example, the base station may configure the UE with a common search space on a PCell or a primary secondary cell (PSCell) in an active downlink BWP.

[0103] For an uplink BWP in a set of configured uplink BWPs, the BS may configure the UE with one or more resource sets for one or more PUCCH transmissions. The UE may receive downlink receptions (e.g., PDCCH or PDSCH) in the downlink BWP according to the configured numerology (e.g., subcarrier spacing and cyclic prefix duration) for the downlink BWP. The UE may transmit uplink transmissions (e.g., PUCCH or PUSCH) in the uplink BWP according to the configured numerology (e.g., subcarrier spacing and cyclic prefix length for the uplink BWP).

[0104] One or more BWP indicator fields may be provided in the downlink control information (DCI). The value of the BWP indicator field may indicate which BWP of a set of configured BWPs is an active downlink BWP for one or more downlink receptions. The value of the one or more BWP indicator fields may indicate an active uplink BWP for one or more uplink transmissions.

[0105] The base station may semi-statically configure the UE with a default downlink BWP in a set of configured downlink BWPs associated with the PCell. If the base station does not provide a default downlink BWP for the UE, the default downlink BWP may be the initial active downlink BWP. The UE may determine which BWP is the initial active downlink BWP based on the CORESET configuration obtained using the PBCH.

[0106] The base station may configure the UE with a BWP inactivity timer value for the PCell. The UE may start or restart the BWP inactivity timer at any appropriate time. For example, the UE may start or restart the BWP inactivity timer when (a) the UE detects a DCI indicating an active downlink BWP other than a default downlink BWP for paired spectrum operation, or (b) the UE detects a DCI indicating an active downlink BWP or an active uplink BWP other than a default downlink BWP or an uplink BWP for unpaired spectrum operation. If the UE does not detect a DCI for a certain period of time (e.g., 1 ms or 0.5 ms), the UE may start the BWP inactivity timer towards expiration (e.g., increasing it from zero to the BWP inactivity timer value or decreasing it from the BWP inactivity timer value to zero). When the BWP inactivity timer expires, the UE may be switched from the active downlink BWP to the default downlink BWP.

[0107] In an embodiment, a base station may semi-statically configure a UE with one or more BWPs, and the UE may switch the active BWP from a first BWP to a second BWP in response to receiving a DCI indicating the second BWP as the active BWP and / or in response to expiration of a BWP inactivity timer (e.g., if the second BWP is a default BWP).

[0108] Downlink and uplink BWP switching (BWP switching refers to switching from a currently active BWP to a currently inactive BWP) may be performed independently in paired spectrum. In unpaired spectrum, downlink and uplink BWP switching may be performed simultaneously. Switching between configured BWPs may occur based on RRC signaling, DCI, expiration of a BWP inactivity timer, and / or initiation of random access.

[0109] FIG. 9 illustrates an example of bandwidth adaptation using three configured BWPs for an NR carrier. A UE configured with three BWPs may be switched from one BWP to another BWP at a switching point. In the example illustrated in FIG. 9, the BWPs include BWP 902 with a bandwidth of 40 MHz and a subcarrier spacing of 15 kHz, BWP 904 with a bandwidth of 10 MHz and a subcarrier spacing of 15 kHz, and BWP 906 with a bandwidth of 20 MHz and a subcarrier spacing of 60 kHz. BWP 902 may be the initial active BWP, and BWP 904 may be the default BWP. The UE may switch between the BWPs at a switching point. In the example of FIG. 9, the UE may switch from BWP 902 to BWP 904 at switching point 908. Switching at switching point 908 may occur for any suitable reason, for example, in response to expiration of a BWP inactivity timer (indicating switching to the default BWP) and / or in response to receiving a DCI indicating BWP 904 as the active BWP. The UE may switch from the active BWP 904 to BWP 906 at switching point 910 in response to receiving a DCI indicating BWP 906 as the active BWP. The UE may switch from the active BWP 906 to BWP 904 at switching point 912 in response to expiration of a BWP inactivity timer and / or in response to receiving a DCI indicating BWP 904 as the active BWP. The UE may switch from the active BWP 904 to BWP 902 at switching point 914 in response to receiving a DCI indicating BWP 902 as the active BWP.

[0110] If the UE is configured for a secondary cell with a default downlink BWP in the set of configured downlink BWP and timer values, the UE procedure for switching the BWP on the secondary cell may be the same / similar to that on the primary cell. For example, the UE may use timer values ​​and default downlink BWP for the secondary cell in the same / similar manner that the UE uses these values ​​for the primary cell.

[0111] To provide a larger data rate, two or more carriers can be aggregated and transmitted simultaneously to and from the same UE using carrier aggregation (CA). The aggregated carriers in CA can be referred to as component carriers (CC). When CA is used, there are many serving cells for the UE and one for the CC. The CC can have three configurations in the frequency domain.

[0112] 10A shows three CA configurations with two CCs. In the intra-band contiguous configuration 1002, two CCs are aggregated in the same frequency band (frequency band A) and are located immediately adjacent to each other in the frequency band. In the intra-band non-contiguous configuration 1004, two CCs are aggregated in the same frequency band (frequency band A) and are separated in frequency band by a gap. In the intra-band configuration 1006, two CCs are located in frequency bands (frequency band A and frequency band B).

[0113] In an embodiment, up to 32 CCs may be aggregated. The aggregated CCs may have the same or different bandwidths, subcarrier spacing, and / or duplexing schemes (TDD or FDD). A serving cell of a UE using CA may have a downlink CC. In the case of FDD, one or more uplink CCs may optionally be configured for a serving cell. The ability to aggregate more downlink carriers than uplink carriers may be useful, for example, when a UE has more data traffic in the downlink than in the uplink.

[0114] When using CA, one of the aggregation cells of the UE may be referred to as a Primary Cell (PCell). The PCell may be a serving cell to which the UE initially connects in RRC connection establishment, re-establishment, and / or handover. The PCell may provide the UE with NAS mobility information and security inputs. The UE may have different PCells. In the downlink, the carrier corresponding to the PCell may be referred to as a Downlink Primary CC (DL PCC). In the uplink, the carrier corresponding to the PCell may be referred to as an Uplink Primary CC (UL PCC). The other aggregation cell for the UE may be referred to as a Secondary Cell (SCell). In an embodiment, the SCell may be configured after the PCell is configured for the UE. For example, the SCell may be configured via an RRC connection reconfiguration procedure. In the downlink, the carrier corresponding to the SCell may be referred to as a Downlink Secondary CC (DL SCC). In the uplink, the carrier corresponding to the SCell may be referred to as an Uplink Secondary CC (UL SCC).

[0115] A configured SCell for a UE may be activated and deactivated based on, for example, traffic and channel conditions. Deactivation of a SCell may mean that PDCCH and PDSCH reception on the SCell is deactivated and PUSCH, SRS, and CQI transmission on the SCell is deactivated. A configured SCell may be activated and deactivated using a MAC CE with respect to FIG. 4B. For example, the MAC CE may use a bitmap (e.g., one bit per SCell) to indicate which SCell (e.g., among a subset of configured SCells) for a UE is activated or deactivated. A configured SCell may be deactivated in response to expiration of a SCell deactivation timer (e.g., one SCell deactivation timer per SCell).

[0116] Downlink control information such as scheduling assignments and scheduling grants for a cell may be transmitted on the cell corresponding to the assignments and grants, known as self-scheduling. DCI for a cell may be transmitted on another cell, known as cross-carrier scheduling. Uplink control information for aggregation cells (e.g., HARQ acknowledgements and channel state feedback such as CQI, PMI, and / or RI) may be transmitted on the PUCCH of the PCell. A large number of aggregated downlink CCs may overload the PUCCH of the PCell. A cell may be divided into multiple PUCCH groups.

[0117] FIG. 10B illustrates an example of how aggregation cells may be configured into one or more PUCCH groups. The PUCCH group 1010 and the PUCCH group 1050 may each include one or more downlink CCs. In the example of FIG. 10B, the PUCCH group 1010 includes three downlink CCs: PCell 1011, SCell 1012, and SCell 1013. The PUCCH group 1050 includes three downlink CCs: PCell 1051, SCell 1052, and SCell 1053 in this example. One or more uplink CCs may be configured as PCell 1021, SCell 1022, and SCell 1023. One or more other uplink CCs may be configured as Primary Scell ​​(PSCell) 1061, SCell 1062, and SCell 1063. Uplink control information (UCI) associated with downlink CCs of PUCCH group 1010, denoted as UCI 1031, UCI 1032, and UCI 1033, may be transmitted on the uplink of PCell 1021. Uplink control information (UCI) associated with downlink CCs of PUCCH group 1050, denoted as UCI 1071, UCI 1072, and UCI 1073, may be transmitted on the uplink of PSCell 1061. In an embodiment, if the aggregation cells depicted in FIG. 10B are not divided into PUCCH group 1010 and PUCCH group 1050, a single uplink PCell and PCell for transmitting UCI associated with downlink CCs may be overloaded. By dividing the transmission of UCI between PCell 1021 and PSCell 1061, the overload may be prevented.

[0118] A cell including a downlink carrier and, optionally, an uplink carrier may be assigned a physical cell ID and a cell index. The physical cell ID or cell index may identify the downlink carrier and / or the uplink carrier of the cell, for example, depending on the context in which the physical cell ID is used. The physical cell ID may be determined using a synchronization signal transmitted on a downlink component carrier. The cell index may be determined using an RRC message. In this disclosure, the physical cell ID may be referred to as a carrier ID, and the cell index may be referred to as a carrier index. For example, when this disclosure refers to a first physical cell ID for a first downlink carrier, this disclosure may mean that the first physical cell ID is for a cell including the first downlink carrier. The same / similar concept may be applied to, for example, carrier activation. When this disclosure indicates that the first carrier is activated, this specification may mean that the cell including the first carrier is activated.

[0119] In CA, the multi-carrier nature of the PHY may be exposed to the MAC. In an embodiment, a HARQ entity may operate on the serving cell. Transport blocks may be generated per assignment / grant per serving cell. Transport blocks and potential HARQ retransmissions of transport blocks may be mapped to the serving cell.

[0120] In the downlink, a base station may transmit (e.g., unicast, multicast, and / or broadcast) one or more reference signals (RS) (e.g., PSS, SSS, CSI-RS, DMRS, and / or PT-RS as shown in FIG. 5A) to the UE. In the uplink, the UE may transmit one or more RS to the base station (e.g., DMRS, PT-RS, and / or SRS as shown in FIG. 5B). The PSS and SSS may be transmitted by the base station and used by the UE to synchronize the UE to the base station. The PSS and SSS may be provided in a synchronization signal (SS) / physical broadcast channel (PBCH) block that includes the PSS, SSS, and PBCH. The base station may periodically transmit bursts of the SS / PBCH block.

[0121] FIG. 11A illustrates an example of a structure and location of an SS / PBCH block. A burst of SS / PBCH blocks may include one or more SS / PBCH blocks (e.g., four SS / PBCH blocks as shown in FIG. 11A). A burst may be transmitted periodically (e.g., every two frames or every 20 ms). A burst may be limited to a half frame (e.g., the first half frame having a duration of 5 ms). It will be appreciated that FIG. 11A is an example, and these parameters (number of SS / PBCH blocks per burst, periodicity of the burst, location of the burst within a frame) may be configured based on, for example, the carrier frequency of the cell in which the SS / PBCH block is transmitted, the numerology or subcarrier spacing of the cell, configuration by the network (e.g., using RRC signaling), or any other suitable factor. In an example, the UE may assume a subcarrier spacing for the SS / PBCH block based on the monitored carrier frequency, unless the wireless network configures the UE to assume a different subcarrier spacing.

[0122] An SS / PBCH block may span one or more OFDM symbols in the time domain (e.g., four OFDM symbols as shown in the example of FIG. 11A) and one or more subcarriers in the frequency domain (e.g., 240 consecutive subcarriers). The PSS, SSS, and PBCH may have a common center frequency. The PSS may be transmitted first and may span, for example, one OFDM symbol and 127 subcarriers. The SSS may be transmitted after the PSS (e.g., the last two symbols) and may span one OFDM symbol and 127 subcarriers. The PBCH may be transmitted after the PSS (e.g., over the next three OFDM symbols) and may span 240 subcarriers.

[0123] The location of the SS / PBCH block in the time and frequency domain may be unknown to the UE (e.g., when the UE is searching for a cell). To find and select a cell, the UE may monitor the carrier for a PSS. For example, the UE may monitor a frequency location within the carrier. If the PSS is not found after a certain duration (e.g., 20 ms), the UE may search for a PSS at a different frequency location within the carrier as indicated by the synchronization raster. If the PSS is found at a location in the time and frequency domain, the UE may determine the location of the SSS and PBCH, respectively, based on the known structure of the SS / PBCH block. The SS / PBCH block may be a cell-defined SS block (CD-SSB). In an embodiment, a primary cell may be associated with the CD-SSB. The CD-SSB may be located on the synchronization raster. In an embodiment, cell selection / search and / or reselection may be based on the CD-SSB.

[0124] The SS / PBCH block may be used by the UE to determine one or more parameters of the cell. For example, the UE may determine a physical cell identifier (PCI) of the cell based on the PSS and SSS sequences, respectively. The UE may determine a location of a frame boundary of the cell based on the location of the SS / PBCH block. For example, the SS / PBCH block may indicate that it was transmitted according to a transmission pattern, where the SS / PBCH block is a known distance from a frame boundary.

[0125] The PBCH may use QPSK modulation and may use forward error correction (FEC). The FEC may use polar coding. One or more symbols spanned by the PBCH may carry one or more DMRSs for demodulation of the PBCH. The PBCH may include an indication of the cell's current system frame number (SFN) and / or SS / PBCH block timing index. These parameters may facilitate time synchronization of the UE to the base station. The PBCH may include a Master Information Block (MIB) used to provide one or more parameters to the UE. The MIB is used to identify the remaining minimum system information (RMSI) with which the UE is associated with the cell. The RMSI may include a System Information Block Type 1 (SIB1). The SIB1 may include information necessary for the UE to access the cell. The UE may use one or more parameters of the MIB to monitor the PDCCH, which may be used to schedule the PDSCH. The PDSCH may include SIB1. The SIB1 may be decoded using the parameters provided in the MIB. The PBCH may indicate the absence of SIB1. The UE may be pointed to a frequency based on the PBCH indicating that SIB1 is not present, and the UE may search for an SS / PBCH block on the frequency to which the UE is pointed.

[0126] The UE may assume that one or more SS / PBCH blocks transmitted with the same SS / PBCH block index are quasi-co-located (QCL'd) (e.g., have the same / similar Doppler spread, Doppler shift, average gain, average delay, and / or spatial Rx parameters). The UE may not assume that the QCL's for SS / PBCH block transmissions have different SS / PBCH block indices.

[0127] SS / PBCH blocks (e.g., blocks within a half frame) may be transmitted in spatial directions (e.g., using different beams across the coverage area of ​​a cell). In an embodiment, a first SS / PBCH block may be transmitted in a first spatial direction using a first beam and a second SS / PBCH block may be transmitted in a second spatial direction using a second beam.

[0128] In an embodiment, within the frequency span of a carrier, a base station may transmit multiple SS / PBCH blocks. In an embodiment, a first PCI of a first SS / PBCH block of the multiple SS / PBCH blocks may be different from a second PCI of a second SS / PBCH block of the multiple SS / PBCH blocks. The PCIs of SS / PBCH blocks transmitted at different frequency locations may be different or may be the same.

[0129] The CSI-RS may be transmitted by a base station and used by a UE to obtain channel state information (CSI). The base station may configure the UE with one or more CSI-RS for channel estimation or any other suitable purpose. The base station may configure the UE with one or more of the same / similar CSI-RS. The UE may measure one or more CSI-RS. The UE may estimate downlink channel conditions and / or generate a CSI report based on measurements of one or more downlink CSI-RS. The UE may provide the CSI report to the base station. The base station may perform link adaptation using feedback provided by the UE (e.g., estimated downlink channel conditions).

[0130] A base station may semi-statically configure a UE with one or more CSI-RS resource sets. The CSI-RS resources may be associated with a location and periodicity in the time and frequency domain. The base station may selectively activate and / or deactivate CSI-RS resources. The base station may indicate to the UE that CSI-RS resources in a CSI-RS resource set are activated and / or deactivated.

[0131] The base station may configure the UE to report CSI measurements. The base station may configure the UE to provide CSI reports periodically, aperiodically, or semi-persistently. For periodic CSI reporting, the UE may be configured with the timing and / or periodicity of the CSI reports. For aperiodic CSI reporting, the base station may request the CSI reports. For example, the base station may instruct the UE to measure configured CSI-RS resources and provide CSI reports on the measurements. For semi-persistent CSI reporting, the base station may configure the UE to periodically transmit and selectively start or stop periodic reports. The base station may configure the UE with the CSI-RS resource set and CSI reports using RRC signaling.

[0132] The CSI-RS configuration may include, for example, one or more parameters indicating up to 32 antenna ports. The UE may be configured to use the same OFDM symbol for the downlink CSI-RS and a control resource set (CORESET) if the downlink CSI-RS and CORESET are spatially QCL'd and resource elements associated with the downlink CSI-RS are outside of a physical resource block (PRB) configured for CORESET. The UE may be configured to use the same OFDM symbol for the downlink CSI-RS and SS / PBCH block if the downlink CSI-RS and SS / PBCH block are spatially QCL'd and resource elements associated with the downlink CSI-RS are outside of a PRB configured for the SS / PBCH block.

[0133] The downlink DMRS may be transmitted by a base station and may be used by a UE for channel estimation. For example, the downlink DMRS may be used for coherent demodulation of one or more downlink physical channels (e.g., PDSCH). An NR network may support one or more variable and / or configurable DMRS patterns for data demodulation. At least one downlink DMRS configuration may support a frontloaded DMRS pattern. The frontloaded DMRS may be mapped to one or more OFDM symbols (e.g., one or two adjacent OFDM symbols). The base station may semi-statically configure the UE with the number (e.g., maximum number) of frontloaded DMRS symbols of the PDSCH. The DMRS configuration may support one or more DMRS ports. For example, in the case of single-user MIMO, the DMRS configuration may support up to eight orthogonal downlink DMRS ports per UE. In the case of multi-user MIMO, the DMRS configuration may support up to four orthogonal downlink DMRS ports per UE. The wireless network may support a common DMRS structure for downlink and uplink (e.g., at least for CP-OFDM). The DMRS position, DMRS pattern, and / or scrambling sequence may be the same or different. The base station may transmit the downlink DMRS and corresponding PDSCH using the same precoding matrix. The UE may use one or more downlink DMRS for coherent demodulation / channel estimation of the PDSCH.

[0134] In an embodiment, a transmitter (e.g., a base station) may use a precoder matrix for a portion of a transmission bandwidth. For example, the transmitter may use a first precoder matrix for a first bandwidth and a second precoder matrix for a second bandwidth. The first precoder matrix and the second precoder matrix may be different based on the first bandwidth being different from the second bandwidth. The UE may assume that the same precoding matrix is ​​used across a set of PRBs. The set of PRBs may be denoted as a precoding resource block group (PRG).

[0135] The PDSCH may include one or more layers. The UE may assume that at least one symbol with a DMRS is present on one or more layers of the PDSCH. Higher layers may configure up to three DMRS for the PDSCH.

[0136] The downlink PT-RS may be transmitted by the base station and may be used by the UE for phase noise compensation. Whether the downlink PT-RS is present depends on the RRC configuration. The presence and / or pattern of the downlink PT-RS may be configured on a UE-specific basis using a combination of RRC signaling and / or an association with one or more parameters used for other purposes (e.g., modulation and coding scheme (MCS)) that may be indicated by DCI. When configured, the dynamic presence of the downlink PT-RS may be associated with one or more DCI parameters including at least the MCS. The NR network may support multiple PT-RS densities defined in the time and / or frequency domain. The frequency domain density, if present, may be associated with at least one configuration of the scheduled bandwidth. The UE may assume the same precoding for the DMRS and PT-RS ports. The number of PT-RS ports may be less than the number of DMRS ports in the scheduled resource. The downlink PT-RS may be restricted to the scheduled time / frequency duration of the UE. The downlink PT-RS may be transmitted on symbols to facilitate phase tracking at the receiver.

[0137] The UE may transmit an uplink DMRS to a base station for channel estimation. For example, the base station may use the uplink DMRS for coherent demodulation of one or more uplink physical channels. For example, the UE may transmit the uplink DMRS on a PUSCH and / or a PUCCH. The uplink DM-RS may span a range of frequencies similar to the range of frequencies associated with the corresponding physical channel. The base station may configure the UE with one or more uplink DMRS configurations. At least one DMRS configuration may support a frontloaded DMRS pattern. The frontloaded DMRS may be mapped to one or more OFDM symbols (e.g., one or two adjacent OFDM symbols). The one or more uplink DMRS may be configured to transmit on one or more symbols of the PUSCH and / or the PUCCH. The base station may semi-statically configure the UE with a number (e.g., a maximum number) of frontloaded DMRS symbols for the PUSCH and / or the PUCCH that the UE may use to schedule single-symbol DMRS and / or dual-symbol DMRS. An NR network may support a common DMRS structure for the downlink and uplink (e.g., for cyclic prefix orthogonal frequency division multiplexing (CP-OFDM)), where the DMRS location, DMRS pattern, and / or scrambling sequence of the DMRS may be the same or different.

[0138] The PUSCH may include one or more layers, and the UE may transmit at least one symbol having a DMRS present on one or more layers of the PUSCH. In an embodiment, higher layers may configure up to three DMRSs for the PUSCH.

[0139] An uplink PT-RS (which may be used by the base station for phase tracking and / or phase noise compensation) may be present or absent depending on the RRC configuration of the UE. The presence and / or pattern of the uplink PT-RS may be configured on a UE-specific basis by a combination of one or more parameters used for other purposes (e.g., modulation and coding scheme (MCS)) that may be indicated by RRC signaling and / or DCI. When configured, the dynamic presence of the uplink PT-RS may be associated with one or more DCI parameters including at least the MCS. The wireless network may support multiple uplink PT-RS densities defined in the time / frequency domain. The frequency domain density, if present, may be associated with at least one configuration of the scheduled bandwidth. The UE may assume the same precoding for the DMRS and PT-RS ports. The number of PT-RS ports may be less than the number of DMRS ports in the scheduled resources. For example, the uplink PT-RS may be limited to the scheduled time / frequency duration of the UE.

[0140] The SRS may be transmitted by the UE to the base station for channel condition estimation to support uplink channel-dependent scheduling and / or link adaptation. The SRS transmitted by the UE may enable the base station to estimate uplink channel conditions at one or more frequencies. The base station scheduler may use the estimated uplink channel conditions to allocate one or more resource blocks for uplink PUSCH transmission from the UE. The base station may semi-statically configure the UE with one or more SRS resource sets. In the case of an SRS resource set, the base station may configure the UE with one or more SRS resources. The SRS resource set applicability may be configured by higher layer (e.g., RRC) parameters. For example, when higher layer parameters indicate beam management, SRS resources in the SRS resource set of one or more SRS resource sets (e.g., having the same / similar time domain behavior, periodic, aperiodic, and / or the like) may be transmitted instantaneously (e.g., simultaneously). The UE may transmit one or more SRS resources in the SRS resource set. An NR network may support aperiodic, periodic, and / or semi-persistent SRS transmission. The UE may transmit SRS resources based on one or more trigger types, which may include higher layer signaling (e.g., RRC) and / or one or more DCI formats. In an embodiment, at least one DCI format may be used for the UE to select at least one of the one or more configured SRS resource sets. SRS trigger type 0 may refer to SRS triggered based on higher layer signaling. SRS trigger type 1 may refer to SRS triggered based on one or more DCI formats. In an embodiment, if the PUSCH and SRS are transmitted in the same slot, the UE may be configured to transmit the SRS after the transmission of the PUSCH and the corresponding uplink DMRS.

[0141] The base station may quasi-statistically configure the UE with one or more SRS configuration parameters indicating at least one of an SRS resource configuration identifier, a number of SRS ports, a time domain behavior of the SRS resource configuration (e.g., an indication of periodic, semi-persistent, or aperiodic SRS), a slot, minislot, and / or subframe level periodicity, an offset for periodic and / or aperiodic SRS resources, a number of OFDM symbols in the SRS resource, a starting OFDM symbol of the SRS resource, an SRS bandwidth, a frequency hopping bandwidth, a periodic shift, and / or an SRS sequence ID.

[0142] The antenna ports are defined such that a channel on which a symbol on an antenna port is carried can be inferred from a channel on which another symbol on the same antenna port is carried. When a first symbol and a second symbol are transmitted on the same antenna port, the receiver may infer a channel (e.g., fade gain, multipath delay, and / or the like) on which a second symbol on an antenna port is carried from a channel on which a first symbol on the antenna port is carried. A first antenna port and a second antenna port may be referred to as quasi-co-located (QCLed) if one or more large-scale characteristics of a channel on which a first symbol on the first antenna port is carried can be inferred from a channel on which a second symbol of the second antenna port is carried. The one or more large-scale characteristics may include at least one of delay spread, Doppler spread, Doppler shift, average gain, average delay, and / or spatial receive (Rx) parameters.

[0143] In a channel using beamforming, beam management is required. Beam management may include beam measurement, beam selection, and beam indication. A beam may be associated with one or more reference signals. For example, a beam may be identified by one or more beamforming reference signals. The UE may perform downlink beam measurement based on a downlink reference signal (e.g., a channel state information reference signal (CSI-RS)) and generate a beam measurement report. The UE may perform a downlink beam measurement procedure after an RRC connection is set up with the base station.

[0144] FIG. 11B illustrates an example of a channel state information reference signal (CSI-RS) mapped to the time and frequency domain. The squares illustrated in FIG. 11B may span resource blocks (RBs) within the bandwidth of a cell. The base station may transmit one or more RRC messages including CSI-RS resource configuration parameters indicating one or more CSI-RS. One or more of the following parameters may be set by higher layer signaling (e.g., RRC and / or MAC signaling) for the CSI-RS resource configuration: CSI-RS resource configuration identity, number of CSI-RS ports, CSI-RS configuration (e.g., symbol and resource element (RE) location within a subframe), CSI-RS subframe configuration (e.g., subframe position, offset, and radio frame periodicity), CSI-RS power parameters, CSI-RS sequence parameters, code division multiplexing (CDM) type parameters, frequency density, transmit comb, quasi-collocation (QCL) parameters (e.g., QCL-scramblingidentity, crs-portscount, mbsfn-subframeconfiglist, csi-rs-configZPid, qcl-csi-rs-configNZPid), and / or other radio resource parameters.

[0145] The three beams shown in FIG. 11B may be configured for a UE in a UE-specific configuration. Three beams are shown in FIG. 11B (Beam #1, Beam #2, and Beam #3), and more or less beams may be configured. Beam #1 may be assigned with CSI-RS 1101, which may be transmitted on one or more subcarriers in the RB of the first symbol. Beam #2 may be assigned with CSI-RS 1102, which may be transmitted on one or more subcarriers in the RB of the second symbol. Beam #3 may be assigned with CSI-RS 1103, which may be transmitted on one or more subcarriers in the RB of the third symbol. By using frequency division multiplexing (FDM), the base station may transmit another CSI-RS associated with another UE's beam using other subcarriers (e.g., not used to transmit CSI-RS 1101) in the same RB. By using time domain multiplexing (TDM), the beam used for a UE may be configured such that the UE's beam uses symbols from the other UE's beam.

[0146] The CSI-RS (e.g., CSI-RS 1101, 1102, 1103) shown in FIG. 11B may be transmitted by a base station and used by a UE for one or more measurements. For example, the UE may measure the reference signal received power (RSRP) of the configured CSI-RS resources. The base station may configure the UE with a reporting configuration, and the UE may report the RSRP measurements to the network (e.g., via one or more base stations) based on the reporting configuration. In one embodiment, the base station may determine one or more transmission configuration indication (TCI) states including some reference signals based on the reported measurement results. In one embodiment, the base station may indicate one or more TCI states to the UE (e.g., via RRC signaling, MAC CE, and / or DCI). The UE may receive a downlink transmission with a receive (Rx) beam determined based on one or more TCI states. In an embodiment, the UE may or may not have beam correspondence capability. If the UE has beam correspondence capability, the UE may determine a spatial domain filter of a transmit (Tx) beam based on the spatial domain filter of the corresponding Rx beam. If the UE does not have beam correspondence capability, the UE may perform an uplink beam selection procedure to determine a spatial domain filter of the Tx beam. The UE may perform an uplink beam selection procedure based on one or more sounding reference signal (SRS) resources configured for the UE by the base station. The base station may select and indicate an uplink beam for the UE based on measurements of one or more SRS resources transmitted by the UE.

[0147] In a beam management procedure, the UE may evaluate (e.g., measure) the channel quality of one or more beam pair links, including a transmit beam transmitted by the base station and a receive beam received by the UE. Based on the evaluation, the UE may transmit a beam measurement report indicating one or more beam pair quality parameters including, for example, one or more beam identities (e.g., beam index, reference signal index, or the like), RSRP, a precoding matrix indicator (PMI), a channel quality indicator (CQI), and / or a rank indicator (RI).

[0148] FIG. 12A illustrates an example of three downlink beam management procedures, P1, P2, and P3. Procedure P1 may enable UE measurements at a transmit (Tx) beam of a transmit receive point (TRP) (or multiple TRPs) to support selection of, for example, one or more base station Tx beams and / or UE Rx beams (shown as ellipses in the top and bottom rows of P1, respectively). Beamforming at a TRP may include a Tx beam sweep of a set of beams (shown as an ellipse rotating in a counterclockwise direction as indicated by the dashed arrow in the top rows of P1 and P2). Beamforming at a UE may include a Rx beam sweep of a set of beams (shown as an ellipse rotating in a clockwise direction as indicated by the dashed arrow in the bottom rows of P1 and P3). Procedure P2 may be used to enable UE measurements at a Tx beam of a TRP (shown as an ellipse rotating in a counterclockwise direction as indicated by the dashed arrow in the top row of P2). The UE and / or base station may perform procedure P2 using a smaller set of beams than used in procedure P1 or using narrower beams than used in procedure P1. This may be referred to as beam refinement. The UE may perform procedure P3 for Rx beam determination by using the same Tx beam at the base station and sweeping the Rx beams at the UE.

[0149] FIG. 12B shows an example of three uplink beam management procedures, U1, U2, and U3. Procedure U1 may be used, for example, to enable the base station to perform measurements on the UE's Tx beams to support the selection of one or more UE Tx beams and / or base station Rx beams (shown as ellipses in the top and bottom rows of U1, respectively). Beamforming at the UE may include, for example, a Tx beam sweep from a set of beams (shown as ellipses rotating in a clockwise direction as shown by the dashed arrow in the bottom rows of U1 and U3). Beamforming at the base station may include, for example, a Rx beam sweep from a set of beams (shown as ellipses rotating in a counterclockwise direction as shown by the dashed arrow in the top rows of U1 and U2). Procedure U2 may be used to enable the base station to adjust its Rx beam when the UE uses a fixed Tx beam. The UE and / or base station may perform procedure U2 using a smaller set of beams than used in procedure P1, or using a narrower beam than used in procedure P1. This may be referred to as beam refinement. The UE may perform procedure U3 to adjust its Tx beam when the base station uses a fixed Rx beam.

[0150] The UE may initiate a beam failure recovery (BFR) procedure based on the detection of a beam failure. The UE may transmit a BFR request (e.g., a preamble, UCI, SR, MAC CE, and / or the like) based on the initiation of the BFR procedure. The UE may detect a beam failure based on a determination that the quality of the beam pair link of the associated control channel is unsatisfactory (e.g., has an error rate higher than an error rate threshold, a received signal power lower than a received signal power threshold, a timer expires, and / or the like).

[0151] The UE may measure the quality of the beam pair link using one or more reference signals (RSs) including one or more SS / PBCH blocks, one or more CSI-RS resources, and / or one or more demodulation reference signals (DMRSs). The quality of the beam pair link may be based on one or more of a block error rate (BLER), an RSRP value, a signal-to-interference-plus-noise ratio (SINR) value, a reference signal received quality (RSRQ) value, and / or a CSI value measured on the RS resource. The base station may indicate that the RS resource is quasi-co-located (QCLed) with one or more DM-RSs of a channel (e.g., a control channel, a shared data channel, and / or the like). The RS resource and one or more DMRSs of the channel may be QCLed when the channel characteristics (e.g., Doppler shift, Doppler spread, average delay, delay spread, spatial Rx parameters, fade, and / or the like) from a transmission to the UE over the RS resource are similar or identical to the channel characteristics from a transmission to the UE over the channel.

[0152] The network (e.g., gNB and / or ng-eNB of the network) and / or the UE may initiate a random access procedure. A UE in RRC_IDLE state and / or a UE in RRC_INACTIVE state may initiate a random access procedure to request a connection setup to the network. The UE may initiate a random access procedure from the RRC_CONNECTED state. The UE may initiate a random access procedure to request uplink resources (e.g., for uplink transmission of SR when there are no available PUCCH resources) and / or to acquire uplink timing (e.g., when the uplink synchronization state is not synchronized). The UE may initiate a random access procedure and request one or more system information blocks (SIBs) (e.g., SIB2, SIB3, and / or other system information such as the like). The UE may initiate a random access procedure for a beam failure recovery request. The network may initiate a random access procedure to establish time alignment for handover and / or for SCell addition.

[0153] Figure 13A shows a four-step contention-based random access procedure. Before the procedure begins, the base station may transmit a configuration message 1310 to the UE. Figure 13A includes the transmission of four messages: Msg1 1311, Msg2 1312, Msg3 1313, and Msg4 1314. Msg1 1311 may include and / or be referred to as a preamble (or random access preamble). Msg2 1312 may include and / or be referred to as a random access response (RAR).

[0154] The configuration message 1310 may be transmitted, for example, using one or more RRC messages. The one or more RRC messages may indicate one or more Random Access Channel (RACH) parameters to the UE. The one or more RACH parameters may include at least one of general parameters (e.g., RACH-configGeneral), cell-specific parameters (e.g., RACH-ConfigCommon), and / or dedicated parameters (e.g., RACH-configDedicated) for one or more random access procedures. The base station may broadcast or multicast one or more RRC messages to one or more UEs. The one or more RRC messages may be UE-specific (e.g., dedicated RRC messages sent to the UE in RRC_CONNECTED and / or RRC_INACTIVE states). The UE may determine time-frequency resources and / or uplink transmit power for transmission of Msg1 1311 and / or Msg3 1313 based on the one or more RACH parameters. Based on the one or more RACH parameters, the UE may determine the receive timing and downlink channel for receiving Msg2 1312 and Msg4 1314.

[0155] The one or more RACH parameters provided in the configuration message 1310 may indicate one or more physical RACH (PRACH) opportunities available for transmission of Msg1 1311. The one or more PRACH opportunities may be predefined. The one or more RACH parameters may indicate one or more available sets of one or more PRACH opportunities (e.g., prach-ConfigIndex). The one or more RACH parameters may indicate an association between (a) one or more PRACH opportunities and (b) one or more reference signals. The one or more RACH parameters may indicate an association between (a) one or more preambles and (b) one or more reference signals. The one or more reference signals may be SS / PBCH blocks and / or CSI-RS. For example, the one or more RACH parameters may indicate the number of SS / PBCH blocks mapped to the PRACH opportunities and / or the number of preambles mapped to the SS / PBCH blocks.

[0156] The one or more RACH parameters provided in the configuration message 1310 may be used to determine the uplink transmission power of Msg1 1311 and / or Msg3 1313. For example, the one or more RACH parameters may indicate a reference power for the preamble transmission (e.g., a received target power and / or an initial power of the preamble transmission). There may be one or more power offsets indicated by the one or more RACH parameters. For example, the one or more RACH parameters may indicate a power ramping step, a power offset between SSB and CSI-RS, a power offset between the transmissions of Msg1 1311 and Msg3 1313, and / or a power offset value between the preamble groups. The one or more RACH parameters may indicate one or more thresholds for which the UE may determine at least one reference signal (e.g., SSB and / or CSI-RS) and / or uplink carrier (e.g., a normal uplink (NUL) carrier and / or a complementary uplink (SUL) carrier).

[0157] Msg1 1311 may include one or more preamble transmissions (e.g., a preamble transmission and one or more preamble retransmissions). An RRC message may be used to configure one or more preamble groups (e.g., Group A and / or Group B). A preamble group may include one or more preambles. The UE may determine a preamble group based on a path loss measurement and / or a size of Msg3 1313. The UE may measure the RSRP of one or more reference signals (e.g., SSB and / or CSI-RS) and determine at least one reference signal having an RSRP above an RSRP threshold (e.g., rsrp-threshold valueSSB and / or rsrp-ThresholdCSI-RS). The UE may select at least one preamble associated with one or more reference signals and / or a selected preamble group, for example, if an association between the one or more preambles and the at least one reference signal is configured by an RRC message.

[0158] The UE may determine the preamble based on one or more RACH parameters provided in the configuration message 1310. For example, the UE may determine the preamble based on a path loss measurement, an RSRP measurement, and / or a size of Msg3 1313. As another example, the one or more RACH parameters may indicate one or more thresholds for determining a preamble format, a maximum number of preamble transmissions, and / or one or more preamble groups (e.g., Group A and Group B). The base station may configure the UE with an association between one or more preambles and one or more reference signals (e.g., SSB and / or CSI-RS) using the one or more RACH parameters. If an association is configured, the UE may determine a preamble to include in Msg1 1311 based on the association. Msg1 1311 may be transmitted to the base station via one or more PRACH opportunities. The UE may use one or more reference signals (e.g., SSB and / or CSI-RS) for preamble selection and PRACH opportunity determination. One or more RACH parameters (eg, ra-ssb-OccasionMskIndex and / or ra-OccasionList) may indicate an association between a PRACH occasion and one or more reference signals.

[0159] The UE may perform a preamble retransmission if no response is received after the preamble transmission. The UE may increase the uplink transmit power for the preamble retransmission. The UE may select an initial preamble transmit power based on a path loss measurement and / or a target received preamble power configured by the network. The UE may determine to retransmit the preamble and may ramp up the uplink transmit power. The UE may receive one or more RACH parameters (e.g., PREAMBLE_POWER_RAMPING_STEP) indicating a ramping step of the preamble retransmission. The ramping step may be the amount of incremental increase of the uplink transmit power for the retransmission. If the UE determines a reference signal (e.g., SSB and / or CSI-RS) that is the same as the previous preamble transmission, the UE may ramp up the uplink transmit power. The UE may count the number of preamble transmissions and / or retransmissions (e.g., PREAMBLE_TRANSMISSION_COUNTER). The UE may determine that the random access procedure has completed unsuccessfully, for example, if the number of preamble transmissions exceeds a threshold configured by one or more RACH parameters (eg, preambleTransMax).

[0160] Msg2 1312 received by the UE may include an RAR. In some scenarios, Msg2 1312 may include multiple RARs corresponding to multiple UEs. Msg2 1312 may be received after or in response to the transmission of Msg1 1311. Msg2 1312 may be scheduled on the DL-SCH and indicated on the PDCCH using a Random Access RNTI (RA-RNTI). Msg2 1312 may indicate that Msg1 1311 was received by the base station. Msg2 1312 may include a time alignment command that the UE may use to adjust the UE's transmission timing, a scheduling grant for the transmission of Msg3 1313, and / or a Temporary Cell RNTI (TC-RNTI). After the UE transmits the preamble, the UE may start a time window (e.g., ra-ResponseWindow) in which it monitors the PDCCH for Msg2 1312. The UE may determine when to start the time window based on the PRACH opportunity the UE uses to transmit the preamble. For example, the UE may start the time window one or more symbols after the last symbol of the preamble (e.g., on the first PDCCH opportunity from the end of the preamble transmission). The one or more symbols may be determined based on numerology. The PDCCH may be within a common search space (e.g., Type1-PDCCH common search space) configured by the RRC message. The UE may identify the RAR based on a Radio Network Temporary Identifier (RNTI). The RNTI may be used in response to one or more events that initiate the random access procedure. The UE may use a Random Access RNTI (RA-RNTI). The RA-RNTI may be associated with the PRACH opportunity on which the UE transmits the preamble. For example, the UE may determine the RA-RNTI based on an OFDM symbol index, a slot index, a frequency domain index, and / or a UL carrier indicator of the PRACH opportunity. Examples of the RA-RNTI may be as follows: RA-RNTI=1+s_id+14×t_id+14×80×f_id+14×80×8×ul_carrier_id where s_id may be the index of the first OFDM symbol of the PRACH opportunity (e.g., 0≦s_id<14), t_id may be the index of the first slot of the PRACH opportunity in the system frame (e.g., 0≦t_id<80), f_id may be the index of the PRACH opportunity in the frequency domain (e.g., 0≦f_id<8), and ul_carrier_id may be the UL carrier used for preamble transmission (e.g., 0 for NUL carrier and 1 for SUL carrier). The UE may transmit Msg3 1313 in response to successful reception of Msg2 1312 (e.g., using resources identified in Msg2 1312). Msg3 1313 may be used for contention resolution, for example, in the contention-based random access procedure shown in FIG. 13A. In some scenarios, multiple UEs may transmit the same preamble to the base station, and the base station may provide the UE with a corresponding RAR. If multiple UEs interpret the RAR as corresponding to themselves, a mismatch may occur. Contention resolution (e.g., use of Msg3 1313 and Msg4 1314) may be used to increase the likelihood that a UE does not mistakenly use the identity of another UE. To perform contention resolution, the UE may include a device identifier (e.g., C-RNTI, if assigned, TC-RNTI included in Msg2 1312, and / or any other suitable identifier) ​​in Msg3 1313.

[0161] Msg4 1314 may be received after or in response to the transmission of Msg3 1313. If a C-RNTI was included in Msg3 1313, the base station uses the C-RNTI to address the UE on the PDCCH. If the UE's unique C-RNTI is detected on the PDCCH, the random access procedure is determined to have been successfully completed. If a TC-RNTI is included in Msg3 1313 (e.g., the UE is in an RRC_IDLE state or is otherwise not connected to the base station), Msg4 1314 is received using the DL-SCH associated with the TC-RNTI. If the MAC PDU is successfully decoded and the MAC PDU matches the CCCH SDU sent (e.g., transmitted) in Msg3 1313 or otherwise includes the corresponding UE contention resolution identity MAC CE, the UE may determine that contention resolution has been successful and / or the UE may determine that the random access procedure has been successfully completed.

[0162] The UE may be configured with a complementary uplink (SUL) carrier and a normal uplink (NUL) carrier. Initial access (e.g., random access procedure) may be supported on the uplink carrier. For example, the base station may configure the UE with two separate RACH configurations, one for the SUL carrier and one for the NUL carrier. For random access in a cell configured with the SUL carrier, the network may indicate which carrier (NUL or SUL) to use. The UE may determine the SUL carrier, for example, if the measured quality of one or more reference signals is lower than a broadcast threshold. Uplink transmissions of the random access procedure (e.g., Msg1 1311 and / or Msg3 1313) may remain on the selected carrier. The UE may switch uplink carriers during the random access procedure (e.g., between Msg1 1311 and Msg3 1313) in one or more cases. For example, the UE may determine and / or switch the uplink carrier for Msg1 1311 and / or Msg3 1313 based on a channel clear assessment (e.g., listen-before-talk).

[0163] FIG. 13B illustrates a two-step contention-free random access procedure. Similar to the four-step contention-based random access procedure illustrated in FIG. 13A, the base station may transmit a configuration message 1320 to the UE before the procedure begins. The configuration message 1320 may be similar in some respects to the configuration message 1310. FIG. 13B includes the transmission of two messages, Msg1 1321 and Msg2 1322. Msg1 1321 and Msg2 1322 may be similar in some respects to Msg1 1311 and Msg2 1312, respectively, illustrated in FIG. 13A. As can be seen from FIG. 13A and FIG. 13B, the contention-free random access procedure may not include messages similar to Msg3 1313 and / or Msg4 1314.

[0164] The contention-free random access procedure shown in Figure 13B may be initiated for beam failure recovery, other SI requests, SCell addition, and / or handover. For example, the base station may indicate or assign to the UE the preamble to be used for Msg1 1321. The UE may receive an indication of the preamble (e.g., ra-PreambleIndex) from the base station via the PDCCH and / or RRC.

[0165] After transmitting the preamble, the UE may start a time window (e.g., ra-ResponseWindow) to monitor the PDCCH of the RAR. In the case of a beam failure recovery request, the base station may configure the UE with a separate time window and / or separate PDCCH within the search space indicated by the RRC message (e.g., recoverySearchSpaceId). The UE may monitor for PDCCH transmissions addressed to the Cell RNTI (C-RNTI) on the search space. In the contention-free random access procedure shown in FIG. 13B, the UE may determine that the random access procedure is successfully completed after or in response to transmitting Msg1 1321 and receiving the corresponding Msg2 1322. The UE may determine that the random access procedure is successfully completed, for example, when the PDCCH transmission is addressed to the C-RNTI. The UE may determine that the random access procedure is successfully completed, for example, if the UE receives an RAR including a preamble identifier corresponding to a preamble transmitted by the UE and / or if the RAR includes a MAC sub-PDU including the preamble identifier. The UE may determine the response as an indication of a response acknowledgment to the SI request.

[0166] Figure 13C shows another two-step random access procedure. Similar to the random access procedure shown in Figures 13A and 13B, the base station may transmit a configuration message 1330 to the UE before the procedure begins. The configuration message 1330 may be similar in some respects to the configuration message 1310 and / or the configuration message 1320. Figure 13C includes the transmission of two messages, namely MsgA 1331 and MsgB 1332.

[0167] MsgA 1331 may be transmitted in an uplink transmission by the UE. MsgA 1331 may include one or more transmissions of a preamble 1341 and / or one or more transmissions of a transport block 1342. The transport block 1342 may include content similar and / or equivalent to the content of Msg3 1313 shown in FIG. 13A. The transport block 1342 may include UCI (e.g., SR, HARQ ACK / NACK, and / or similar). The UE may receive MsgB 1332 after or in response to the transmission of MsgA 1331. MsgB 1332 may include content similar and / or equivalent to the content of Msg2 1312 (e.g., RAR) shown in FIG. 13A and FIG. 13B and / or the content of Msg4 1314 shown in FIG. 13A.

[0168] The UE may initiate the two-step random access procedure of FIG. 13C for licensed and / or unlicensed spectrum. The UE may determine whether to initiate the two-step random access procedure based on one or more factors. The one or more factors may be the radio access technology in use (e.g., LTE, NR, and / or similar), whether the UE has a valid TA, the cell size, the RRC state of the UE, the type of spectrum (e.g., licensed vs. unlicensed), and / or any other suitable factor.

[0169] The UE may determine radio resources and / or uplink transmit power for the preamble 1341 and / or the transport block 1342 included in the MsgA 1331 based on the two-step RACH parameters included in the configuration message 1330. The RACH parameters may indicate a modulation and coding scheme (MCS), time-frequency resources, and / or power control for the preamble 1341 and / or the transport block 1342. The time-frequency resources for the transmission of the preamble 1341 (e.g., PRACH) and the time-frequency resources for the transmission of the transport block 1342 (e.g., PUSCH) may be multiplexed using FDM, TDM, and / or CDM. The RACH parameters may enable the UE to determine the receive timing and downlink channel for monitoring and / or receiving the MsgB 1332.

[0170] The transport block 1342 may include data (e.g., delay sensitive data), a UE identifier, security information, and / or device information (e.g., International Mobile Subscriber Identity (IMSI)). The base station may send MsgB 1332 in response to MsgA 1331. MsgB 1332 may include at least one of a preamble identifier, a timing advance command, a power control command, an uplink grant (e.g., radio resource allocation and / or MCS), a UE identifier for contention resolution, and / or an RNTI (e.g., C-RNTI or TC-RNTI). The UE may determine that the two-step random access procedure is successfully completed when the preamble identifier in MsgB 1332 matches the preamble transmitted by the UE and / or the UE identifier in MsgB 1332 matches the UE identifier (e.g., transport block 1342) in MsgA 1331.

[0171] The UE and the base station may exchange control signaling, which may be referred to as L1 / L2 control signaling, and may originate from the PHY layer (e.g., Layer 1) and / or the MAC layer (e.g., Layer 2). The control signaling may include downlink control signaling transmitted from the base station to the UE and / or uplink control signaling transmitted from the UE to the base station.

[0172] The downlink control signaling may include downlink scheduling assignments, uplink scheduling grants indicating uplink radio resources and / or transport formats, slot format information, preemption indications, power control commands, and / or any other suitable signaling. A UE may receive the downlink control signaling in a payload transmitted by a base station on a Physical Downlink Control Channel (PDCCH). The payload transmitted on the PDCCH may be referred to as Downlink Control Information (DCI). In some scenarios, the PDCCH may be a Group Common PDCCH (GC-PDCCH) that is common to a group of UEs.

[0173] The base station may attach one or more cyclic redundancy check (CRC) parity bits to the DCI to facilitate detection of transmission errors. When the DCI is intended for a UE (or a group of UEs), the base station may scramble the CRC parity bits with an identifier of the UE (or an identifier of the group of UEs). Scrambling the CRC parity bits with an identifier may include a modulo-2 addition (or exclusive OR operation) of the identifier value and the CRC parity bits. The identifier may include a Radio Network Temporary Identifier (RNTI), which is a 16-bit value.

[0174] DCIs may be used for different purposes. The purpose may be indicated by the type of RNTI used to scramble the CRC parity bits. For example, a DCI with CRC parity bits scrambled with a paging RNTI (P-RNTI) may indicate paging information and / or system information change notification. The P-RNTI may be predefined as "FFFE" in hexadecimal. A DCI with CRC parity bits scrambled with a system information RNTI (SI-RNTI) may indicate a broadcast transmission of system information. The SI-RNTI may be predefined as "FFFF" in hexadecimal. A DCI with CRC parity bits scrambled with a random access RNTI (RA-RNTI) may indicate a random access response (RAR). A DCI with CRC parity bits scrambled with a cell RNTI (C-RNTI) may indicate a unicast transmission of dynamic scheduling and / or a random access of PDCCH order trigger. A DCI with CRC parity bits scrambled with the Temporary Cell RNTI (TC-RNTI) may indicate contention resolution (e.g., Msg3 similar to Msg3 1313 shown in FIG. 13A). Encodings of other RNTIs configured by the base station in the UE include Configured Scheduling RNTI (CS-RNTI), Transmit Power Control-PUCCH RNTI (TPC-PUCCH-RNTI), Transmit Power Control-PUSCH RNTI (TPC-PUSCH-RNTI), Transmit Power Control-SRS RNTI (TPC-SRS-RNTI), Interruption RNTI (INT-RNTI), Slot Format Indication RNTI (SFI-RNTI), Semi-Persistent CSI RNTI (SP-CSI-RNTI), Modulation and Coding Scheme Cell RNTI (MCS-C-RNTI), and / or the like.

[0175] Depending on the purpose and / or content of the DCI, the base station may transmit the DCI in one or more DCI formats. For example, DCI format 0_0 may be used for scheduling the PUSCH in the cell. DCI format 0_0 may be a fallback DCI format (e.g., has a compact DCI payload). DCI format 0_1 ​​may be used for scheduling the PUSCH in the cell (e.g., has a larger DCI payload than DCI format 0_0). DCI format 1_0 may be used for scheduling the PDSCH in the cell. DCI format 1_0 may be a fallback DCI format (e.g., has a compact DCI payload). DCI format 1_1 may be used for scheduling the PDSCH in the cell (e.g., has a larger DCI payload than DCI format 1_0). DCI format 2_0 may be used to provide a slot format indication to a group of UEs. DCI format 2_1 may be used to inform a group of UEs of physical resource blocks and / or OFDM symbols that the UE assumes are not intended for transmission to the UE. DCI format 2_2 may be used for transmission of transmit power control (TPC) commands for PUCCH or PUSCH. DCI format 2_3 may be used for transmission of a group of TPC commands for SRS transmission by one or more UEs. DCI formats for new features may be defined in future releases. DCI formats may have different DCI sizes or share the same DCI size.

[0176] After scrambling the DCI with the RNTI, the base station may process the DCI with channel coding (e.g., polar coding), rate matching, scrambling, and / or QPSK modulation. The base station may map the coded and modulated DCI onto resource elements used and / or configured for the PDCCH. Based on the payload size of the DCI and / or the coverage of the base station, the base station may transmit the DCI via the PDCCH occupying several consecutive control channel elements (CCEs). The number of consecutive CCEs (referred to as an aggregation level) may be 1, 2, 4, 8, 16, and / or any other suitable number. A CCE may include a number of resource element groups (REGs) (e.g., 6). A REG may include a resource block in an OFDM symbol. The mapping of the coded and modulated DCI onto resource elements may be based on a mapping of CCEs and REGs (e.g., CCE to REG mapping).

[0177] FIG. 14A illustrates an example of a CORESET configuration for a bandwidth portion. A base station may transmit DCI via a PDCCH on one or more control resource sets (CORESETs). A CORESET may include time-frequency resources on which a UE attempts to decode DCI using one or more search spaces. A base station may configure a CORESET in the time-frequency domain. In the example of FIG. 14A, a first CORESET 1401 and a second CORESET 1402 occur at a first symbol in a slot. The first CORESET 1401 overlaps with the second CORESET 1402 in the frequency domain. A third CORESET 1403 occurs at a third symbol in a slot. A fourth CORESET 1404 occurs at a seventh symbol of the slot. The CORESETs may have different numbers of resource blocks in the frequency domain.

[0178] FIG. 14B illustrates an example of CCE-to-REG mapping for DCI transmission on a CORESET and PDCCH processing. The CCE-to-REG mapping may be interleaved (e.g., for the purpose of providing frequency diversity) or non-interleaved (e.g., for the purpose of facilitating interference coordination and / or frequency selective transmission of control channels). A base station may implement different or the same CCE-to-REG mapping on different CORESETs. A CORESET may be associated with a CCE-to-REG mapping by an RRC configuration. A CORESET may be configured with an antenna port quasi-co-location (QCL) parameter. The QCL parameter of an antenna port may indicate the QCL information of a demodulation reference signal (DMRS) for PDCCH reception in the CORESET.

[0179] The base station may send an RRC message to the UE including configuration parameters of one or more CORESETs and one or more search space sets. The configuration parameters may indicate an association between the search space set and the CORESET. The search space set may include a set of PDCCH candidates formed by CCEs at a given aggregation level. The configuration parameters may indicate the number of PDCCH candidates monitored per aggregation level, a PDCCH monitoring periodicity and a PDCCH monitoring pattern, one or more DCI formats monitored by the UE, and / or whether the search space set is a common search space set or a UE-specific search space set. The set of CCEs in the common search space set may be predefined and known to the UE. The set of CCEs in the UE-specific search space set may be configured based on the UE's identity (e.g., C-RNTI).

[0180] As shown in FIG. 14B, the UE may determine time-frequency resources of the CORESET based on the RRC message. The UE may determine a CCE-REG mapping (e.g., interleaved or non-interleaved, and / or mapping parameters) for the CORESET based on a configuration parameter of the CORESET. The UE may determine a number of search space sets (e.g., up to 10) configured on the CORESET based on the RRC message. The UE may monitor a set of PDCCH candidates according to the configuration parameter of the search space set. The UE may monitor a set of PDCCH candidates in one or more CORESETs to detect one or more DCIs. The monitoring may include decoding one or more PDCCH candidates of the set of PDCCH candidates according to a monitored DCI format. The monitoring may include decoding DCI content of one or more PDCCH candidates having possible (or configured) PDCCH positions, possible (or configured) PDCCH formats (e.g., the number of CCEs in the common search space, the number of PDCCH candidates, and / or the number of PDCCH candidates in the UE-specific search space), and possible (or configured) DCI formats. The decoding may be referred to as blind decoding. The UE may determine a valid DCI for the UE in response to a CRC check (e.g., scrambling bits to CRC parity bits of the DCI matching the RNTI value). The UE may process information included in the DCI (e.g., scheduling assignments, uplink grants, power control, slot format indication, downlink preemption, and / or the like).

[0181] The UE may transmit uplink control signaling (e.g., uplink control information (UCI)) to the base station. The uplink control signaling may include a hybrid automatic repeat request (HARQ) acknowledgement for the received DL-SCH transport block. The UE may transmit the HARQ acknowledgement after receiving the DL-SCH transport block. The uplink control signaling may include channel state information (CSI) indicating a channel quality of the physical downlink channel. The UE may transmit the CSI to the base station. The base station may determine transmission format parameters (e.g., including multiple antennas and forming schemes) for the downlink transmission based on the received CSI. The uplink control signaling may include a scheduling request (SR). The UE may transmit an SR indicating that uplink data is available for transmission to the base station. The UE may transmit the UCI (e.g., a HARQ acknowledgement (HARQ-ACK), a CSI report, an SR, etc.) via a physical uplink control channel (PUCCH) or a physical uplink shared channel (PUSCH). A UE may transmit uplink control signaling via the PUCCH using one of several PUCCH formats.

[0182] There may be five PUCCH formats, and the UE may determine the PUCCH format based on the size of the UCI (e.g., the number of uplink symbols of the UCI transmission and the number of UCI bits). PUCCH format 0 may have a length of one or two OFDM symbols and may include two or less bits. The UE may transmit UCI in the PUCCH resource using PUCCH format 0 if the transmission is more than one or two symbols and the number of HARQ-ACK information bits with positive or negative SR (HARQ-ACK / SR bits) is one or two. PUCCH format 1 may occupy between 4-14 OFDM symbols and may include two or less bits. The UE may use PUCCH format 1 if the transmission is four or more symbols and the number of HARQ-ACK / SR bits is one or two. PUCCH format 2 may occupy one or two OFDM symbols and may include more than two bits. The UE may use PUCCH format 2 if the transmission is more than one or two symbols and the number of UCI bits is two or more. PUCCH format 3 may occupy between 4 and 14 OFDM symbols and may include more than 2 bits. The UE may use PUCCH format 3 if the transmission is four or more symbols, the number of UCI bits is two or more, and the PUCCH resource does not include an orthogonal cover code. PUCCH format 4 may occupy between 4 and 14 OFDM symbols and may include more than 2 bits. The UE may use PUCCH format 4 if the transmission is four or more symbols, the number of UCI bits is two or more, and the PUCCH resource includes an orthogonal cover code.

[0183] The base station may transmit configuration parameters of multiple PUCCH resource sets to the UE, for example, using an RRC message. Multiple PUCCH resource sets (e.g., up to four sets) may be configured on the uplink BWP of the cell. A PUCCH resource set may be configured with a PUCCH resource set index, multiple PUCCH resources with PUCCH resources identified by a PUCCH resource identifier (e.g., pucch-Resourceid), and / or a number (e.g., a maximum number) of UCI information bits that the UE may transmit using one of the multiple PUCCH resources in the PUCCH resource set. When configured with multiple PUCCH resource sets, the UE may select one of the multiple PUCCH resource sets based on a total bit length of the UCI information bits (e.g., HARQ-ACK, SR, and / or CSI). If the total bit length of the UCI information bits is less than or equal to two, the UE may select a first PUCCH resource set with a PUCCH resource set index equal to "0". If the total bit length of the UCI information bits is greater than 2 and less than or equal to the first configuration value, the UE may select a second PUCCH resource set having a PUCCH resource set index equal to "1". If the total bit length of the UCI information bits is greater than the first configuration value and less than or equal to the second configuration value, the UE may select a third PUCCH resource set having a PUCCH resource set index equal to "2". If the total bit length of the UCI information bits is greater than the second configuration value and less than or equal to a third value (e.g., 1406), the UE may select a fourth PUCCH resource set having a PUCCH resource set index equal to "3".

[0184] After determining a PUCCH resource set from the multiple PUCCH resource sets, the UE may determine a PUCCH resource from the PUCCH resource set for UCI (HARQ-ACK, CSI, and / or SR) transmission. The UE may determine the PUCCH resource based on a PUCCH resource indicator in a DCI (e.g., DCI format 1_0 or DCI format 1_1) received on the PDCCH. The 3-bit PUCCH resource indicator of the DCI may indicate one of the eight PUCCH resources in the PUCCH resource set. Based on the PUCCH resource indicator, the UE may transmit the UCI (HARQ-ACK, CSI, and / or SR) using the PUCCH resource indicated by the PUCCH resource indicator in the DCI.

[0185] FIG. 15 illustrates an example of a wireless device 1502 communicating with a base station 1504 according to an embodiment of the disclosure. The wireless device 1502 and base station 1504 may be part of a mobile communication network, such as the mobile communication network 100 shown in FIG. 1A, the mobile communication network 150 shown in FIG. 1B, or other communication network. Although only one wireless device 1502 and one base station 1504 are shown in FIG. 15, it will be understood that a mobile communication network may include more than one UE and / or more than one base station having the same or similar configuration as shown in FIG. 15.

[0186] The base station 1504 may connect the wireless device 1502 to a core network (not shown) via wireless communication over an air interface (or radio interface) 1506. The direction of communication from the base station 1504 to the wireless device 1502 over the air interface 1506 is known as the downlink, and the direction of communication from the wireless device 1502 to the base station 1504 over the air interface is known as the uplink. Downlink transmissions may be separated from uplink transmissions using FDD, TDD, and / or some combination of the two duplexing techniques.

[0187] In the downlink, data transmitted from the base station 1504 to the wireless device 1502 may be provided to the processing system 1508 of the base station 1504. The data may be provided to the processing system 1508 by, for example, a core network. In the uplink, data transmitted from the wireless device 1502 to the base station 1504 may be provided to the processing system 1518 of the wireless device 1502. The processing system 1508 and the processing system 1518 may implement Layer 3 and Layer 2 OSI functions to process the data for transmission. Layer 2 may include, for example, the SDAP layer, the PDCP layer, the RLC layer, and the MAC layer with respect to Figures 2A, 2B, 3, and 4A. Layer 3 may include the RRC layer with respect to Figure 2B.

[0188] After being processed by the processing system 1508, data to be transmitted to the wireless device 1502 may be provided to a transmit processing system 1510 of the base station 1504. Similarly, after being processed by the processing system 1518, data to be transmitted to the base station 1504 may be provided to a transmit processing system 1520 of the wireless device 1502. The transmit processing system 1510 and the transmit processing system 1520 may implement the OSI functions of Layer 1. Layer 1 may include the PHY layer with respect to FIGS. 2A, 2B, 3, and 4A. For transmit processing, the PHY layer may perform, for example, forward error correction coding of transport channels, interleaving, rate matching, mapping of transport channels to physical channels, modulation of physical channels, multiple input multiple output (MIMO) or multi-antenna processing, and / or the like.

[0189] At the base station 1504, a receive processing system 1512 may receive uplink transmissions from the wireless device 1502. At the wireless device 1502, a receive processing system 1522 may receive downlink transmissions from the base station 1504. The receive processing system 1512 and the receive processing system 1522 may implement the OSI functions of Layer 1. Layer 1 may include the PHY layer with respect to FIGS. 2A, 2B, 3, and 4A. For receive processing, the PHY layer may perform, for example, error detection, forward error correction decoding, deinterleaving, demapping of transport channels to physical channels, demodulation of physical channels, MIMO or multi-antenna processing, and / or the like.

[0190] 15, the wireless device 1502 and the base station 1504 may include multiple antennas. The multiple antennas may be used to implement one or more MIMO or multi-antenna techniques, such as spatial multiplexing (e.g., single-user MIMO or multi-user MIMO), transmit / receive diversity, and / or beamforming. In other examples, the wireless device 1502 and / or the base station 1504 may have a single antenna.

[0191] Processing system 1508 and processing system 1518 may be associated with memory 1514 and memory 1524, respectively. Memory 1514 and memory 1524 (e.g., one or more non-transitory computer-readable media) may store computer program instructions or code that may be executed by processing system 1508 and / or processing system 1518 to perform one or more functions discussed in the present application. Although not shown in FIG. 15 , transmit processing system 1510, transmit processing system 1520, receive processing system 1512, and / or receive processing system 1522 may be coupled to memory (e.g., one or more non-transitory computer-readable media) that stores computer program instructions or code that may be executed to perform one or more of their respective functions.

[0192] The processing system 1508 and / or the processing system 1518 may include one or more controllers and / or one or more processors. The one or more controllers and / or the one or more processors may include, for example, a general purpose processor, a digital signal processor (DSP), a microcontroller, an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) and / or other programmable logic devices, discrete gate and / or transistor logic, discrete hardware components, on-board units, or any combination thereof. The processing system 1508 and / or the processing system 1518 may perform at least one of signal coding / processing, data processing, power control, input / output processing, and / or any other functionality that may enable the wireless device 1502 and the base station 1504 to operate in a wireless environment.

[0193] The processing system 1508 and / or the processing system 1518 may be connected to one or more peripheral devices 1516 and one or more peripheral devices 1526, respectively. The one or more peripheral devices 1516 and one or more peripheral devices 1526 may include software and / or hardware that provide features and / or functionality, such as a speaker, a microphone, a keypad, a display, a touchpad, a power source, a satellite transceiver, a universal serial bus (USB) port, a hands-free headset, a frequency modulation (FM) radio unit, a media player, an Internet browser, an electronic control unit (e.g., for a vehicle), and / or one or more sensors (e.g., an accelerometer, a gyroscope, a temperature sensor, a radar sensor, a lidar sensor, an ultrasonic sensor, a light sensor, a camera, and / or the like). The processing system 1508 and / or the processing system 1518 may receive user input data and / or provide user output data from the one or more peripheral devices 1516 and / or the one or more peripheral devices 1526. The processing system 1518 in the wireless device 1502 can receive power from a power source and / or can be configured to distribute power to other components in the wireless device 1502. The power source can include one or more power sources, such as a battery, a solar cell, a fuel cell, or any combination thereof. The processing system 1508 and / or the processing system 1518 can be connected to a GPS chipset 1517 and a GPS chipset 1527, respectively. The GPS chipset 1517 and the GPS chipset 1527 can be configured to provide geographic location information of the wireless device 1502 and the base station 1504, respectively.

[0194] FIG. 16A illustrates an example structure for uplink transmission. A baseband signal representing a physical uplink shared channel may perform one or more functions. The one or more functions may include at least one of: scrambling, modulating scramble bits to generate complex-valued symbols, mapping complex-valued modulation symbols onto one or several transmission layers, transform precoding to generate complex-valued symbols, precoding the complex-valued symbols, mapping the precoded complex-valued symbols onto resource elements, generating complex-valued time-domain single carrier frequency division multiple access (SC-FDMA) or CP-OFDM signals to antenna ports, and / or the like. In an example, if transform precoding is enabled, an SC-FDMA signal for uplink transmission may be generated. In an example, if transform precoding is not enabled, a CP-OFDM signal for uplink transmission may be generated according to FIG. 16A. These functions are illustrated as examples, and it is anticipated that other mechanisms may be implemented in various embodiments.

[0195] 16B shows an example structure for modulation and upconversion of a base-band signal to a carrier frequency. The base-band signal may be a complex-valued SC-FDMA or CP-OFDM base-band signal and / or a complex-valued Physical Random Access Channel (PRACH) base-band signal for an antenna port. Filtering may be used before transmission.

[0196] 16C illustrates an exemplary structure of a downlink transmission. A baseband signal representing a physical downlink channel can perform one or more functions. The one or more functions may include scrambling of coded bits in a codeword to be transmitted on the physical channel, modulation of the scrambled bits to generate complex-valued modulation symbols, mapping of the complex-valued modulation symbols onto one or several transmission layers, precoding of the complex-valued modulation symbols on the layers for transmission on the antenna ports, mapping of the complex-valued modulation symbols of the antenna ports to resource elements, generation of a complex-valued time-domain OFDM signal per antenna port, and / or the like. These functions are illustrated as examples, and it is anticipated that other mechanisms may be implemented in various embodiments.

[0197] 16D shows another exemplary structure for modulation and upconversion of a base-band signal to a carrier frequency. The base-band signal may be a complex-valued OFDM base-band signal for an antenna port. Filtering may be used before transmission.

[0198] The wireless device may receive one or more messages (e.g., RRC messages) from a base station including configuration parameters for multiple cells (e.g., primary cell, secondary cell). The wireless device may communicate with at least one base station (e.g., two or more base stations for dual connectivity) via the multiple cells. The one or more messages (e.g., as part of the configuration parameters) may include physical, MAC, RLC, PCDP, SDAP, RRC layer parameters for configuring the wireless device. For example, the configuration parameters may include parameters for configuring physical and MAC layer channels, bearers, etc. For example, the configuration parameters may include parameters indicating values ​​of timers for the physical layer, MAC layer, RLC layer, PCDP layer, SDAP layer, RRC layer, and / or communication channels.

[0199] When a timer is started, it may start running and continue running until it is stopped or expires. A timer may be started if it is not running or restarted if it is running. A timer may be associated with a value (e.g., a timer may be started or restarted from a value, or may be started from zero and expire when the value is reached). A timer's duration may not be updated until the timer is stopped or expires (e.g., due to a BWP switch). A timer may be used to measure a time period / window of a process. When this specification refers to implementations and procedures related to one or more timers, it will be understood that there are multiple ways to implement one or more timers. For example, it will be understood that one or more of multiple ways to implement a timer may be used to measure a time period / window for a procedure. For example, a random access response window timer may be used to measure a window time for receiving a random access response. In an embodiment, the time difference between two timestamps may be used instead of the start and expiration of the random access response window timer. When the timer is restarted, the process for measuring the time window may be restarted. Another example implementation may be provided for restarting the measurement of the time window.

[0200] A UE may access a cell as a portion of a frequency spectrum for wireless communication. The UE may receive a broadcast signal including access information of the cell, e.g., a synchronization signal block (SSB) and / or a system information block (SIB, e.g., SIB1). A cell, e.g., a serving cell, may be associated with one or more SSBs. SIB1 (e.g., transmitted by one or more SSBs) may indicate frequency information of the serving cell (e.g., via servingCellConfigCommon and / or servingCellConfigCommonSIB). The serving cell may include a downlink (DL) carrier and one or more uplink (UL) carriers (e.g., (normal) UL and / or supplemental UL). The serving cell configuration includes a downlink configuration of the DL carriers (e.g., via downlinkConfigCommon and / or downlinkConfigCommonSIB) and / or an uplink configuration of one or more UL carriers of the cell (e.g., uplinkConfigCommon and / or uplinkConfigCommonSIB). A carrier may be referred to as a component carrier.

[0201] Throughout this disclosure, uplink (UL) may refer to communications directed from a mobile / wireless device to a base station / network, and downlink (DL) may refer to communications directed from a base station / network to a mobile / wireless device / UE.

[0202] The downlink configuration may indicate basic parameters of the DL carrier and transmission thereon, including frequency information of the DL carrier. The frequency information of the DL carrier may indicate a list of one or more frequency bands to which the DL carrier belongs (e.g., via frequencyBandList), an offset of the DL carrier to point A (offsetToPointA), and / or a set of carriers for different subcarrier spacings (SCS, numerology) used in the DL BWP of the serving cell. Multiple bands may be defined, e.g., for 5G and / or 6G, each with a respective center frequency. Each band (e.g., n1, n2, ..., n25, n26, ..., n99 for FR1, and n257, n258, ..., nFR262 for FR2) may be defined with a duplex mode (TDD and / or FDD), a range of uplink and downlink frequencies, and an allowed channel bandwidth (e.g., 5MHz, 10MHz, ..., 50MHz, 200MHz, 400MHz).

[0203] A frequency band may be a range of frequencies in a spectrum between two limits used in communications. A frequency band may be a range of frequencies that is defined and dedicated to a particular type of service or radio technology. The 5G New Radio (5G NR) frequency band may be separated into two different frequency ranges. First, there is Frequency Range 1 (FR1), which includes sub-6 GHz frequency bands, some of which are traditionally used by legacy standards, but which will be extended to cover potential new spectrum offerings (e.g., 410 MHz to 7125 MHz). The other is Frequency Range 2 (FR2), which includes frequency bands from 24.25 GHz to 52.6 GHz. In one embodiment, a frequency band may be defined for FR3 (e.g., above 72 GHz).

[0204] A DL carrier consists of one or more DL Bandwidth Parts (BWPs). Each DL BWP may include a portion of the frequency resources of the DL carrier. A DL BWP configuration may indicate the frequency domain location and bandwidth of this BWP, as well as the SCS used in the BWP of (all) channels and (reference) signals.

[0205] The uplink configuration may indicate basic parameters of the UL carrier (e.g., NUL and / or SUL carrier) and transmissions thereon, including frequency information of the UL carrier, which may indicate a list of one or more frequency bands to which the UL carrier belongs (e.g., via frequencyBandList), the absolute frequency of a reference resource block (a common RB0, e.g., via absoluteFrequencyPointA, whose lowest subcarrier may be referred to as point A), and / or a set of carriers with different subcarrier spacings (SCS, numerology) used in the UL BWP of the serving cell and / or UL carrier.

[0206] A UL carrier (e.g., a NUL carrier and / or a SUL carrier) may include one or more UL Bandwidth Parts (BWPs). Each UL BWP may include a portion of the frequency resources of the UL carrier. A UL BWP configuration may indicate the frequency domain location and bandwidth of this BWP, as well as the SCS used in the BWP for (all) channels and (reference) signals.

[0207] An architectural consideration is dual connectivity (DC) operation involving a first RAT (e.g., Enhanced Universal Terrestrial Radio Access (E-UTRA)) and a second RAT (e.g., NR). In one example of dual connectivity (DC) operation involving E-UTRA and NR, E-UTRA is the master. In another example of DC operation involving E-UTRA and NR, NR is the master. Dual connectivity operation involving only NR serving cells (e.g., NR Primary Cell (PCell) and NR PSCell) is also envisioned.

[0208] A standalone deployment of a first RAT (e.g., NR) can be single or multi-carrier (e.g., NR carrier aggregation, CA, or dual connectivity with NR PCell and NR PSCell). A non-standalone (NSA) deployment of a first RAT (e.g., NR) refers to a dual connectivity (DC) deployment including a second RAT (e.g., E-UTRA), for example, where there is a Long Term Evolution (LTE) PCell and NR PSCell (which can be one or more LTE SCells and one or more NR SCells). The LTE PCell and NR PSCell are respectively composed of a Master Cell Group (MCG) and a Secondary Cell Group (SCG). The MSG and SCG are more commonly referred to as Cell Groups (CGs). The MCG and SCG can be composed of one or more additional serving cells, for example, one or more LTE secondary cells (SCells) in the MCG and one or more SCells in the SCG.

[0209] Carrier aggregation (CA) is commonly used in RATs (e.g., NR and LTE systems) to improve the transmission and reception data rates of communication devices. In CA, a UE typically operates initially on a single serving cell, called a primary cell (Pcell). The Pcell is operated on a component carrier of a frequency band. The UE is then configured by the network with one or more secondary serving cells (Scells). Each Scell ​​can correspond to a component carrier (CC) of the same frequency band (intra-band CA) or a different frequency band (inter-band CA) as the frequency band of the CC corresponding to the Pcell. For the UE to transmit and receive data on the Scell, the Scell ​​may need to be activated by the network (e.g., by receiving downlink shared channel (DL-SCH) information on a physical downlink shared channel (PDSCH) or by transmitting uplink shared channel (UL-SCH) on a physical uplink shared channel (PUSCH). The Scell ​​may also be deactivated and later reactivated as needed via activation / deactivation signaling. A UE may be configured with carrier aggregation to aggregate a frequency division duplexed (FDD) carrier, a time division duplexed (TDD) carrier, or both FDD and TDD carriers. The UE may indicate its carrier aggregation capabilities via capabilities, including whether it supports CA on the downlink and whether it supports CA on the uplink.

[0210] A wireless system may incorporate multiple uplink enhancement technologies. For example, there are three uplink enhancement technologies in 3GPP 5G NR Rel. 15: EUTRA-NR Dual Connectivity (EN-DC), Uplink Carrier Aggregation (CA), and Supplemental Uplink (SUL).

[0211] The above mechanisms are designed to address the problem of NR coverage enhancement. In all the above scenarios, a UE may be configured with a first carrier (e.g., an LTE carrier, and / or an SUL carrier) in a lower frequency band (e.g., an FDD band) and a second carrier (e.g., an NR carrier, and / or a NUL carrier) in a higher frequency band (e.g., a TDD band). The lower frequency band carrier may have a larger coverage area. The higher frequency carrier may have a smaller coverage area. The UE may transmit data either under the first carrier coverage (i.e., the lower frequency band carrier with larger coverage) or under both the first carrier and the second carrier coverage (i.e., the higher frequency carrier with smaller coverage). Thus, the problem of user coverage at the edge of the cell may be solved.

[0212] Commercial UEs, limited by antenna design complexity and low transmit power, typically support two transmit channels (2Tx). In the above uplink enhancement scenario, one Tx of the UE transmitter may be used for a first carrier (e.g., an LTE carrier, and / or a first NR carrier, and / or a SUL carrier), and the other Tx of the UE transmitter may be used for a second carrier (e.g., a 5G NR carrier, and / or a second NR carrier, and / or a NUL carrier).

[0213] FIG. 17A illustrates an example application scenario of EN-DC deployment. The difference between 4G and 5G coverage is illustrated in the figure. In area A, both 4G and 5G coverage exist, so an EN-DC capable UE may transmit data via 4G and / or 5G networks. Commercially available terminals generally support two transmission channels (2Tx), so one Tx may be used for 4G and another Tx for 5G NR. In area B, there is 4G coverage, so the UE may transmit data via the 4G network, e.g., not via the 5G network.

[0214] FIG. 17B shows an example of an uplink operation mode of a UE in area A and area B according to FIG. 17A. A mobile device supporting EN-DC has two simultaneous radio connections to the Evolved Packet Core (EPC), one via 5G NR and the other via LTE. However, since the UE uses one Tx for 5G NR, the uplink dual-stream capability of 5G NR is limited, which means that the peak uplink data throughput is, for example, 74% of what can be achieved with 5G SA. In general, in a non-standalone (NSA) architecture, 5G uplink throughput is improved compared to 4G, but is still lower than 5G standalone (SA). Although the coverage of 5G NR is not improved, in areas without 5G coverage where both signaling and traffic can be transmitted via 4G, the user experience is not significantly worse compared to the coverage of a 4G network.

[0215] FIG. 18A shows an example application scenario of UL inter-band CA. In area A with coverage of NR carrier 1 and NR carrier 2, UL CA can be activated. In area B, with coverage of one carrier, UE transmits data using one carrier. Inter-band carrier aggregation aggregates carriers of different operating bands. For example, 3GPP may be compatible with 13 inter-band CA operating bands involving FR1, such as CA_n3-n78, CA_n28-n78, etc. In areas with good coverage of two aggregated carriers, uplink CA can be used to improve spectrum utilization. However, since most mobile devices support two transmission channels (2Tx), each of which supports two carriers, UL CA may limit uplink dual-stream performance over TDD-NR, resulting in capacity loss.

[0216] FIG. 18B shows an example of an uplink operation mode of a UE in area A and area B according to FIG. 18A. FDD-NR usually adopts a mid-range or low-range band that provides better uplink coverage than TDD-NR. Therefore, FDD-NR can be used to provide 5G services beyond the TDD-NR coverage area to improve user experience. For example, when the uplink data rate at the cell edge is 2 Mbps, if FDD-NR 2.1 GHz (20 MHz bandwidth) and TDD-NR 3.5 GHz (100 MHz bandwidth) are aggregated, the coverage can be improved by 17.8% compared with SA-based TDD-NR single carrier. UL inter-band CA cannot use uplink dual stream, which may have a negative impact on capacity. For example, when 2.1 GHz (20 MHz bandwidth) and 3.5 GHz (100 MHz bandwidth) are aggregated, the uplink peak data rate of a single user is reduced to 80% of the rate of uplink peak data with 3.5 GHz in SA mode. In this case, the gNB does not activate uplink CA but activates single carrier mode to maximize resource utilization. It can be clarified that UL CA does not negatively impact capacity in all scenarios. The single user uplink throughput of CA is directly related to the bandwidth and uplink duty ratio (of TDD-NR carrier) of the two aggregated component carriers (CC1 and CC2). For example, when CC1 is a TDD-NR carrier (50 MHz bandwidth and 2.5 ms dual periodic frame structure) and CC2 is an FDD-NR carrier (20 MHz bandwidth). The uplink peak throughput of UL CA increases by about 8% compared to the uplink peak throughput of dual-stream TDD-NR single carrier. CA technology has been introduced since the 4G era and has been successfully deployed and commercialized worldwide. NR CA has been included since 3GPP Rel-15. Intra-band CA can aggregate multiple frequency carriers of the same band to improve user experience.However, the throughput of inter-band CA may in some cases be limited by the number of transmission channels of a terminal.

[0217] FIG. 19A shows an example of supplemental uplink coverage. A supplemental uplink (SUL) is introduced to extend the uplink coverage by providing a supplemental uplink (usually sub-3 GHz band). In the SUL, a DL frequency band (NR frequency band) and two uplink frequency bands (one NR frequency band and one SUL frequency band) are configured in the same cell. When the uplink coverage of the NR carrier is good, the UE transmits and receives data using the NR carrier. When the UE is moving beyond the uplink coverage of the NR carrier, the UE transmits data using the SUL carrier. The UE can dynamically select UL NR or SUL for data transmission, but the two carriers cannot be used simultaneously. The uplink operating band of the SUL is defined similarly to the uplink operating band of the corresponding FDD-LTE / FDD-NR operating band and must be shared with the existing network (4G or 5G). The SUL band cannot be used alone because it may include the uplink. For example, 3GPP is compatible with eight combinations of SUL and NR bands, including the n78, n79, and SUL band combination definitions.

[0218] Figure 19B shows an example application scenario of SUL: In area A, with good coverage of TDD-NR, the UE uses TDD-NR for data transmission. In area B, beyond the uplink coverage of TDD-NR, the UE switches to the SUL band for data transmission.

[0219] FIG. 19C shows an example of an uplink operation mode of a UE in Area A and Area B according to FIG. 19B. SUL may be implemented in sub-3 GHz bands, which have better uplink coverage than TDD-NR bands, and thus may improve user experience. For example, in a dense urban area where the cell edge uplink data rate is 2 Mbps, if SUL 2.1 GHz (20 MHz bandwidth) and TDD-NR 3.5 GHz (100 MHz bandwidth) are deployed for networking, the network coverage may be increased by 17.8% compared to that of TDD-NR single carrier and SA architecture. In the TDD-NR coverage area, SUL does not affect the peak throughput of a single user, since TDD-NR is used to transmit and receive data. The disadvantage of SUL is that the common 5G NR bands and SUL bands are more dependent on each other, since they need to be in the same cell, which limits its applicability. SUL technology improves uplink coverage by using sub-3 GHz bands for uplink transmission. SUL defines a new paired spectrum between TDD-NR and SUL, and SUL is obtained by sharing spectrum with 4G networks. Therefore, 5G may be co-sited with 4G, which limits the flexibility of 5G deployment and brings new problems to network deployment.

[0220] As seen in the UL scenario above, for commercial UEs using one Tx for 5G NR, the peak UL data throughput is much lower than the achievable throughput because the uplink dual-stream capability of 5G NR cannot be used. In 3GPP Rel. 16, UL Tx switching was introduced as a new feature to enhance EN-DC, UL CA, and SUL performance. UL Tx switching can maximize uplink resource utilization with respect to UE capabilities. It uses one Tx channel for either Carrier 1 or Carrier 2, and the other Tx channel only for Carrier 2.

[0221] A transmitter (Tx) of a wireless device may have / include one or more (e.g., two) antennas / Tx chains. Throughout this disclosure, the terms "antenna" and / or "Tx chain" may be used interchangeably and / or to refer to a physical antenna connector (e.g., of a respective antenna unit) of a UE that may integrate hardware and software to transmit / radiate / propagate wireless signals into the air oriented as a specific beam. Here, an antenna may include an array / group of multiple antenna elements that generate signals based on beamforming and / or MIMO / mass MIMO. Throughout this disclosure, the following terms may be used interchangeably: Tx, antenna, transmit antenna, transmitter antenna, transmission antenna, Tx antenna, transmit channel, Tx channel, transmission channel, transmit chain, Tx chain, Tx RF chain, transmission chain, physical antenna port. In some embodiments, "Tx" may be used in shorthand to refer to the above concepts.

[0222] The antenna may include one or more RF components and / or antenna arrays configured to transmit and / or receive wireless signals. The antenna may be coupled to the radio front-end circuitry and may be any type of antenna capable of wirelessly transmitting and receiving data and / or signals. In some embodiments, the antenna may include one or more omnidirectional sector, or panel antennas operable to transmit / receive wireless signals, for example, from 2 GHz to 66 GHz. An omnidirectional antenna may be used to transmit / receive wireless signals in any direction, a sector antenna may be used to transmit / receive wireless signals from devices in a particular area, and a panel antenna may be a line-of-sight antenna used to transmit / receive wireless signals in a relatively straight line. In some instances, the use of more than one antenna may be referred to as MIMO. In certain embodiments, the antenna may be separate from the network node and may be connectable to the network node via an interface or port. The RF interface may be configured to provide a communication interface to RF components such as a transmitter, a receiver, and an antenna.

[0223] For example, an advanced antenna system (AAS) is the combination of an AAS radio with a set of AAS features. The AAS radio consists of an antenna array tightly integrated with the hardware and software required to transmit and receive radio signals, as well as signal processing algorithms that support the execution of AAS functions. Compared to conventional systems, this solution offers much greater adaptability and steerability in terms of adapting the antenna radiation pattern to rapidly changing traffic and multipath radio propagation conditions. Furthermore, multiple signals may be received or transmitted simultaneously with different radiation patterns. Multiple antenna techniques, referred to herein as AAS features, include beamforming and MIMO. Applying AAS features to an AAS radio results in significant performance improvements due to the higher degrees of freedom provided by a larger number of radio chains, also referred to as mass MIMO.

[0224] For beamforming, the UE may use multiple antennas to control the wavefront direction by appropriately weighting the magnitude and phase of individual antenna signals in an array of multiple antenna elements. That is, the same signal is transmitted from multiple antennas with sufficient space (at least 1 / 2 wavelength) between them. Thus, at any given location, the receiver receives multiple copies of the same signal. Depending on the receiver's location, the signals may be in opposite phases, destructively averaging each other, or constructively summed if different copies are in the same phase, or anything in between. By adjusting the phase and amplitude of the transmitted signals, constructive addition of the corresponding signals at the base station receiver can be achieved, which increases the received signal strength, and therefore the uplink throughput of the UE. The more antenna elements there are, the higher the gain.

[0225] In digital beamforming (also known as baseband beamforming or precoding), the signal is pre-coded (amplitude and phase correction) in baseband processing before RF transmission. Multiple beams (one per user) can be formed simultaneously from the same set of antenna elements. In analog beamforming, the signal phase of the individual antenna signals is adjusted in the RF domain. Analog beamforming affects the radiation pattern and gain of the antenna array, thus improving coverage. Unlike digital beamforming, one beam can be formed per set of antenna elements.

[0226] Spatial multiplexing, referred to here as MIMO, is the ability to transmit multiple data streams, called layers, using the same time and frequency resources, where each data stream can be beamformed. The purpose of MIMO is to increase throughput. MIMO is built on the basic principle that when the received signal quality is high, it is better to receive multiple data streams with reduced power per stream than one stream at full power. When the received signal quality is high and the streams do not interfere with each other, the potential is large. When the mutual interference between the streams increases, the potential decreases. The number of layers / data streams that can be supported can be referred to as a "rank". To distinguish between UL layers, the UE needs to have at least as many Tx antennas as layers, e.g., 2Tx to support two-layer (or two-port) transmission.

[0227] Antenna port may generally be used as a general term for signal transmission under the same channel conditions. For each mode of operation where independent channels are assumed (e.g., SISO vs. MIMO), a separate logical antenna port may be defined. Signals transmitted from different antenna ports may experience different "radio channels" even if the set of antennas is located at the same site. In some cases, it is important that the transmissions share the same antenna port (e.g., quasi-co-located). OFDM symbols transmitted over the same antenna port are subject to the same channel conditions. This helps the base station to estimate the channel using a reference signal (e.g., DMRS) and use that information in decoding the information content on the physical channel (e.g., PUSCH / PUCCH). According to the definition in the 3GPP® specification, antenna ports are defined such that the channel on which a symbol on an antenna port is carried can be inferred from the channel on which another symbol on the same antenna port is carried. MIMO exploits this property (different radio channels) over different antenna ports to transmit multiple parallel data streams. It is important to understand that antenna ports are an abstract concept. There is a difference between logical antenna ports and physical antenna elements. A particular transmission uses particular antenna ports, which are then mapped onto one or more physical antenna elements.

[0228] FIG. 20 illustrates an example of a wireless device transmitter antenna. Logical antenna ports are mapped to physical antenna ports as shown in the figure. The mapping of antenna ports to physical antennas is controlled by specific beam forming, as signals must be transmitted on specific antenna ports to form the desired beam. Two antenna ports may be mapped to one physical antenna port, and / or a single mapped antenna port may be mapped to multiple physical antenna ports.

[0229] To determine the characteristic channel of an antenna port, the UE may perform a separate channel estimation for each antenna port. A separate reference signal suitable for estimating the respective channel may be defined for each antenna port. The manner in which these logical antenna ports are assigned to the UE's physical transmit antennas may be up to the UE and may vary between UEs of the same type (due to different operating conditions) and between UEs from different manufacturers. The UE may not explicitly inform the base station of the mapping performed, rather the base station may automatically take this into account during demodulation.

[0230] For UL channel estimation, it depends on whether time division duplexing (TDD) or frequency division duplexing (FDD) is used. For TDD, the same frequency is used for both UL and DL transmission. Since the radio channel is reciprocal (same for UL and DL), detailed short-term channel estimates from UL transmissions of known signals can be used to determine the DL transmission beam. This is called reciprocal-based beamforming. For full channel estimation, signals should be transmitted from each UE antenna and across all frequencies. For FDD, where different frequencies are used for UL and DL, the channel is not fully reciprocal.

[0231] UE transmitter characteristics may be specified at the UE antenna connector with single or multiple transmit antennas. For UEs with integrated antennas, a reference antenna with 0 dB gain may be assumed. Transmitter requirements for UL MIMO operation may apply when the UE transmits on two ports of the same CDM group. The UE may use higher MPR (Maximum Power Reduction Allowed) values ​​outside this limit.

[0232] In case of inter-band carrier aggregation with one uplink carrier allocated to one NR band, transmitter power requirements may apply. In case of inter-band carrier aggregation with uplink allocated to two NR bands, the UE maximum output power should be measured across all component carriers from the different bands. If each band has a separate antenna connector, the maximum output power is measured as the sum of the maximum output power at each UE antenna connector. The measurement period shall be at least one subframe (1 ms).

[0233] For uplink transmission, the UE may reconfigure / retune some radio frequency (RF) hardware (and / or Tx chains, e.g., filters and / or duplexers) between two carriers, e.g., from the first carrier to the second carrier or vice versa. This reconfiguration / retune may be referred to as moving / switching the Tx chain between carriers. In effect, UL Tx switching between two carriers involves reconfiguring / retune of the UL Tx chain / antenna from the center frequency of the first carrier to the center frequency of the second carrier (or vice versa). The same UL Tx chain / antenna / antenna connector may be used for uplink transmission over the first carrier (e.g., before switching) and the second carrier (e.g., after switching). UL Tx switching may be in response to receiving a scheduling command and / or a TDD UL symbol / slot / subframe, and is therefore also referred to as dynamic UL Tx switching.

[0234] Throughout this disclosure, the following terms may be used interchangeably: Tx switching, UL switching, carrier switching, UL carrier switching, UL Tx switching, UL transmit switching, UL transmit channel switching, UL Tx chain switching, UL Tx antenna switching, Tx antenna switching, dynamic UL Tx switching.

[0235] Figure 21A shows an example of uplink Tx switching for a UE with 2Tx. As shown in the figure, UL Tx switching allows for two modes of operation: Mode 1, where one Tx channel is used for a 2.1 GHz carrier and the other for a 3.5 GHz carrier, and Mode 2, where one Tx channel is switched to 3.5 GHz and the other is still used for 3.5 GHZ allowing for TDD-NR dual stream transmission. Uplink Tx switching is used when switching between Mode 1 and Mode 2.

[0236] Figure 21B shows examples of transmission options for UL Tx switching. Since UE capabilities vary from terminal to terminal, option 1 and option 2 are further defined in Rel-16 as shown in the figure. In option 1, the UE can transmit data over carrier 1 and carrier 2 in time division mode (TDM), but not simultaneously. This option may be called "switched uplink". In option 2, on the terminal side, carrier 1 and carrier 2 can be flexibly aggregated in either TDM mode or simultaneous transmission mode. This option may be called "dual uplink".

[0237] FIG. 22A shows an example of an uplink operation mode of a UE with uplink Tx switching in an EN-DC scenario. In uplink Tx switching (EN-DC), in the uplink time slot of TDD-NR, the Tx channel that originally supported LTE is switched to the TDD-NR frequency band, so that the UE uses dual stream in the uplink, and in other time slots, Tx returns to LTE. With respect to the UE capability and the factors of the radio environment, the UE can operate in different modes as shown in FIG. 22A. Uplink Tx switching is used to improve the uplink capacity. In uplink Tx switching, in the uplink time slot of TDD-NR, the dual stream is maintained, and in other time slots, the UE uses the conventional EN-DC mode, and as a result, the uplink peak throughput is increased by about 17% of that of TDD-NR in SA architecture.

[0238] FIG. 22B shows an example of an uplink operation mode of a UE with uplink Tx switching in an inter-band CA scenario. When uplink Tx switching is activated for inter-band CA, in TDD-NR, the UL time slot UE can transmit data in dual stream. For example, when close to a cell tower, the UE can use inter-band CA with uplink Tx switching to further improve capacity and reduce delay. At the cell edge, the UE can use FDD frequency band to transmit data, while maintaining FDD and TDD carrier aggregation in the downlink to improve user experience. Inter-band CA can flexibly support option 1 and option 2 of uplink Tx switching. The UE works in one of the modes shown in FIG. 22B, which depends on the UE capability and radio environment. Furthermore, 3GPP Rel-16 expands the frequency band combinations of carrier aggregation to 78, and by integrating with uplink Tx switching, CA can improve 5G performance in coverage, capacity, and delay.

[0239] With uplink Tx switching, a UE can connect to both FDD and TDD carriers simultaneously, even at the cell edge, which solves the problem of lack of 5G access due to limited uplink. For example, for TDD-NR with 3.5 GHz and 100 MHz bandwidth, and FDD-NR frequency band of 2.1 GHz utilized for carrier aggregation, when the cell edge uplink data rate is 2 Mbps, adopting CA with uplink Tx switching can increase the network capacity by 17.8% compared with a network with single carrier TDD-NR. When TDD-NR with 3.5 GHz (100 MHz bandwidth) aggregates FDD-NR with 2.1 GHz (20 MHz bandwidth) with uplink Tx switching, the uplink peak throughput capacity is improved by 20%. Uplink Tx switching can increase the availability of uplink time slots to 100%, and thus the HARQ RTT can be reduced by 25% without the uplink data required to wait for TDD-NR uplink time slots. 3GPP Rel-15 introduces inter-band CA with simultaneous transmission on two carriers, which may result in capacity loss without dual-stream transmission of TDD-NR on the uplink. With uplink Tx switching, this limitation is eliminated by transmitting data of FDD-NR and TDD-NR carriers in TDM mode. CA with uplink Tx switching maximizes spectrum utilization by maximizing spectrum utilization in both time and frequency domains and integrating with the power boost feature on TDD-NR carriers to achieve a better user experience.

[0240] FIG. 22C shows an example of an uplink operation mode of a UE with uplink Tx switching in a SUL scenario. With uplink Tx switching, the SUL can integrate both TDD-NR and SUL time-frequency resources into the TDD-NR coverage area, thereby increasing the uplink capacity. The SUL supports option 1 (TDM mode) with uplink Tx switching. Depending on the radio environment, the UE operates in the mode shown in FIG. 22C. When close to the cell tower, the UE switches between the TDD-NR and SUL frequency bands for data transmission. At the cell edge, the SUL carrier is used to provide uplink coverage. Thus, the SUL with uplink Tx switching can improve uplink throughput, reduce delay, and improve coverage compared to the SUL without uplink Tx switching. With uplink Tx switching, the uplink time-frequency resources of the SUL can be assigned to the UE, and the single-user uplink capacity can be increased by 20%. Up to 100% of the uplink time slots can be available, and the HARQ RTT can be reduced by nearly 20%.

[0241] Some LTE-NR aggregation combinations of channels across two bands may be considered difficult to achieve because simultaneous uplink transmissions on these bands, for example from a base station to a wireless device, result in inter-modulation (IM) products in the downlink (DL) to the band. For example, this may occur for inter-band frequency division duplexing (FDD)-FDD and time division duplexing (TDD)-TDD combinations. This means that there are channel combinations across two bands that are not difficult to achieve, which means that a wireless device may support dual simultaneous uplinks for the combination of bands. Here, the channels may be a portion of the spectrum.

[0242] For example, for aggregation combinations where IM products are caused due to simultaneous multiple uplink (UL) from the wireless device to the base station, transmitter to DL receiver in the wireless device, any IM issues will depend on the actual output power of the UL, power balance, allocation, desired signal level, and other interference. Different wireless device implementations will then have different performance. In an ideal scenario, the BS may reliably obtain channel state information (CSI) reports and PHRs, and then take action on known band combinations if IM can be distinguished from other external interference.

[0243] A UE that supports uplink CA between carriers can be assumed to have a dedicated transmit (Tx) chain for each carrier and can therefore support CA without any restrictions. On the other hand, there may be UEs that may share some hardware (e.g., Tx antennas, power amplifiers, phase-locked loops, transmitter chain circuitry, etc.) across two carriers and therefore may require special handling (e.g., via scheduling) to ensure proper operation. For example, a UE may have two Tx chains and can transmit on the uplink on two carriers, but with some restrictions. Since such a UE has two Tx chains, it cannot transmit 1 Tx on carrier 1 and 2 Tx on carrier 2 (e.g., to support two-tier multiple-input multiple-output (MIMO) on carrier 2), and therefore the UE may support either case 1 or case 2 for transmitting on the uplink.

[0244] A dual UL implementation is certainly possible at higher cost in terms of additional RF components, e.g. two TX digital front-ends, an additional TX phase-locked loop (PLL), an additional TX measurement receiver, power management between the two ULs (in different stacks), a multiplexer filter required after the PA (duplexer replaced by a multiplexer), and isolation between the TX paths.

[0245] A switching gap may be required to allow the UE enough time to switch between two carriers (moving / reconfiguring some hardware (or Tx chains) from carrier 1 to carrier 2 or vice versa). The network (NW) needs to provide a switching gap in one of the carriers and also needs to provide enough additional relaxation for the UE Physical Uplink Shared Channel (PUSCH) processing time, which is typically the time between the end of the uplink (UL) grant and the start of the PUSCH.

[0246] When configuring a serving cell with an uplink carrier, for example for dual connectivity and / or carrier aggregation, the network may send an inquiry for UE radio access capability information (e.g., UECapabilityEnquiry). If the network needs (additional) UE radio access capability information, it initiates the procedure to the UE in RRC_CONNECTED. The UE may receive the inquiry from the base station, for example, via an RRC message. The UE may set the content of the capability information (e.g., UECapabilityInformation) message based on the request field of the inquiry message. For example, if the ue-CapabilityRAT-RequestList includes a UE-CapabilityRAT-Request with rat-Type set to nr, the UE shall include in the ue-CapabilityRAT-ContainerList a UE-CapabilityRAT-Container of type UE-NR-Capability and rat-Type set to nr. The UE may include a list of supported band combinations and feature sets (e.g., supportedBandCombinationList, featureSets, and featureSetCombinations).

[0247] The UE may send an RRC message including UE capability information. The UE capability information may include a list of band combinations (e.g., BandCombinationList) supported by the UE. The list of band combinations may include a list of NR CA, NR non-CA, and / or MR-DC band combinations (including DL-only or UL-only bands).

[0248] In one embodiment, the inquiry may include a request for UL Tx switching (e.g., uplinkTxSwitchRequest). In response, the UE may transmit a list of band combinations that the UE may support for UL Tx switching (e.g., BandCombination-UplinkTxSwitch). For example, the UE may include in its list of supported band combinations for UL Tx switching (e.g., supportedBandCombinationList-UplinkTxSwitch) as many NR-only / E-UTRA-NR band combinations that support UL TX switching as possible from the list of candidate band combinations, starting from the first input.

[0249] The list of supported band combination(s) for UL Tx switching may include a list of supported band pairs(s) (e.g., supportedBandPairListNR) and / or a support option for uplink Tx switching (e.g., uplinkTxSwitching-OptionSupport). For example, the support option may indicate a "switched UL" mode (e.g., TDM transmission), or a "dual UL" mode (simultaneous transmission), or both modes. For example, the support option may indicate whether power boosting for UL Tx switching is supported (e.g., uplinkTxSwitching-PowerBoosting).

[0250] Each band pair of the supported band pairs for UL Tx switching includes a first frequency band and a second frequency band. The capability information indicates, for each band pair (e.g., ULTxSwitchingBandPair), an index of the first frequency band (e.g., bandIndexUL1) and an index of the second frequency band (e.g., bandIndexUL2) for simultaneous transmission. The capability information may also indicate, for each band pair, a switching gap / period associated with the two frequency bands of the band pair (e.g., uplinkTxSwitchingPeriod). For example, the switching gap / period may be a duration of microseconds (e.g., 35us, 140us, or 210us).

[0251] The network may configure one or more cells for the UE. For example, the network may send an RRC message indicating one or more cell groups (e.g., CellGroupConfig). The RRC message may include configuration parameters for one or more serving cells, e.g., Pcell and / or SPcell and / or Scell, for the cell group (MCG and / or SCG). Each of the one or more serving cells may include one or more uplink carriers (e.g., UL (NUL) and / or SUL). The RRC message may include a parameter indicating an option, e.g., switched UL or dual UL, for UL Tx switching within the cell group (e.g., uplinkTxSwitchingOption), e.g., based on UE capability information. The RRC message may include a parameter indicating whether power boosting is enabled for UL Tx switching within the cell group (e.g., uplinkTxSwitchingPowerBoosting).

[0252] The network may configure one or more serving cells for the UE, which may be an SpCell or SCell of an MCG or SCG. The UE may receive one or more RRC messages including configuration parameters of the one or more serving cells. The configuration parameters of the serving cells may indicate a downlink configuration and / or an uplink configuration. For example, the configuration parameters of the serving cells may indicate one or more downlink BWPs of the serving cell. For example, the configuration parameters of the serving cells may indicate at least one uplink carrier of the serving cell, e.g., UL (NUL) and / or SUL. In the case of an uplink carrier, the configuration parameters may indicate one or more UL BWPs. In the case of an uplink carrier, the configuration parameters may indicate that UL Tx switching is configured (e.g., uplinkTxSwitching).

[0253] The UL Tx switching configuration associated with a cell's uplink carrier may indicate whether the configured uplink carrier is "carrier 1" or "carrier 2" for dynamic UL Tx switching (e.g., via uplinkTxSwitchingCarrier). For example, UL "carrier 1" could be one transmit antenna connector and UL "carrier 2" could be two transmit antenna connectors. For example, in the case of inter-band UL CA or SUL, the network configures one of the two uplink carriers involved in dynamic UL TX switching as carrier 1 and the other as carrier 2. In the case of (NG)EN-DC, the network always configures the NR carrier as carrier 2.

[0254] The UL Tx switching configuration associated with a cell's uplink carrier may indicate the location of the UL Tx switching period (e.g., via uplinkTxSwitchingPeriodLocation). For example, a Boolean parameter / field may indicate whether the location of the UL Tx switching period is configured on this respective UL carrier. In case of inter-band UL CA or SUL, the network configures this field for one of the uplink carriers involved in dynamic UL TX switching and configures this field to FALSE on the other carrier. In case of (NG)EN-DC, the network always configures this field for an NR carrier (i.e., in case of (NG)EN-DC, the UL switching period always occurs on an NR carrier).

[0255] FIG. 23A and FIG. 23B show examples of UL Tx switching period positions. A time mask for switching between two uplink carriers is shown in FIG. 23A and FIG. 23B. The switching time mask may be applicable to an uplink band pair. For example, the uplink band pair may be associated with an inter-band UL CA configuration and / or a SUL configuration and / or a dual connectivity (e.g., NR-DC and / or EN / DC and / or NE-DC and / or MR-DC). The two uplink carriers may be in different bands with different carrier frequencies. The UL Tx switching period / gap (e.g., uplinkTxSwitchingPeriod, N TX1-TX2) may be present for each band combination associated with the two uplink carriers and / or transmitted to the network. For example, when the capability uplinkTxSwitchingPowerBoosting is present and IEpowerboostingTxSwitching is set to 1, NR UL Carrier 1 may be one transmit antenna connector and NR UL Carrier 2 may be two transmit antenna connectors, with a 3 dB boost on maximum output power. The UE may support switching between single-tier transmission with one antenna port and two-tier transmission with two antenna ports on the two uplink carriers according to scheduling commands and / or rank adaptation. In one embodiment, both single-tier and two-tier transmission with two antenna ports, as well as single-tier transmission with one antenna port, may be supported on NR UL Carrier 2.

[0256] The switching period shown in Figures 23A and 23B is located in either NR carrier 1 or carrier 2 as indicated in the RRC signaling (e.g., uplinkTxSwitchingPeriodLocation). Figure 23A shows an example time mask for switching between UL carrier 1 and UL carrier 2, where the switching period is located in carrier 1. Figure 23B shows an example time mask for switching between UL carrier 1 and UL carrier 2, where the switching period is located in carrier 2. The length of the uplink switching period may be less than the value indicated by the UE capability uplinkTxSwitchingPeriod. The requirement may apply in case of co-located and synchronous network deployment for two uplink carriers. The requirement may apply in case of a single TAG for two uplink carriers, e.g., the same uplink timing for the two carriers.

[0257] The UE may be configured to switch between uplink Tx frames if one or more conditions are met and / or if the UE is configured for UL Tx switching (uplinkTxSwitching). TX1-TX2 Uplink transmissions may be omitted during switching gap / period N TX1-TX2 is indicated by the UE capability uplinkTxSwitchingPeriod for each band combination associated with two uplink carriers. The UE may indicate the capability of uplink switching using a parameter for the band combination (e.g., BandCombination-UplinkTxSwitch). For that band combination, the UE may be configured in an MCG using E-UTRA radio access and in an SCG using NR radio access (EN-DC). For that band combination, the UE may be configured with uplink carrier aggregation. For that band combination, the UE may be configured with a serving cell having two uplink carriers with a higher layer parameter of supplementaryUplink (SUL). One or more conditions may exist for which the switching gap / period and the location of the switching gap may be defined as follows:

[0258] T0-T offset If uplink switching is triggered for an uplink transmission starting at T0 after T0, the UE may cancel the uplink switching and / or offset It may not be expected to trigger any other new uplink switching to occur before T0 due to any other uplink transmissions scheduled after T offset is the UE procedure time defined for the uplink transmission that triggers the switch.

[0259] The UE is UL =max(μ UL,1, μ UL,2 ), and μ UL,1corresponds to the subcarrier spacing of the active UL BWP of one uplink carrier before the switching gap, and μ UL,2 corresponds to the subcarrier spacing of the active UL BWP of the other uplink carrier after the switching gap.

[0260] The UE may indicate a capability of uplink switching (e.g., with BandCombination-UplinkTxSwitch) for a band combination for which the UE may be configured with an MCG using E-UTRA radio access and with an SCG using NR radio access (EN-DC). The UE may be configured with uplink switching (e.g., with the parameter uplinkTxSwitching).

[0261] The UE may be configured with a switched UL transmission mode (e.g., uplinkTxSwitchingOption set to "switchedUL"). offset The UE may transmit on the uplink based on previously received DCI or based on higher layer configuration. The UE may transmit an NR uplink that follows an E-UTRA uplink on another uplink carrier. The UE may transmit an NR uplink that follows an E-UTRA uplink on another uplink carrier. The UE may transmit an NR uplink that follows an E-UTRA uplink on another uplink carrier during a switching period / gap N TX1-TX2 The UE may not be expected to transmit for the duration of the switching period / gap N of either of the two carriers. The UE may transmit an E-UTRA uplink that follows an NR uplink on another uplink carrier. TX1-TX2 A UE may not be expected to transmit for a duration of 100 ms. A UE may not be expected to transmit simultaneously on the NR uplink and E-UTRA uplink. If a UE is scheduled or configured to transmit any NR uplink transmission that overlaps with an E-UTRA uplink transmission, the NR uplink transmission may be dropped.

[0262] The UE may be configured in dual UL transmission mode (e.g., uplinkTxSwitchingOption is set to “dualUL”). offset The UE may transmit on the uplink based on previously received DCI or based on higher layer configuration. The UE may transmit an NR2 port uplink that follows an E-UTRA uplink on another uplink carrier. The UE may transmit an NR2 port uplink that follows an E-UTRA uplink on another uplink carrier. The UE may transmit an NR2 port uplink that follows an E-UTRA uplink on another uplink carrier during a switching period / gap N TX1-TX2 The UE may not be expected to transmit for the duration of the switching period / gap N of either of the two carriers. The UE may transmit an E-UTRA uplink that occurs after an NR2 port uplink on another uplink carrier. The UE may transmit for the duration of the switching period / gap N of either of the two carriers. TX1-TX2 The UE may not be expected to transmit for a duration of tdm-PatternConfig. The UE may not be expected to transmit two-port transmissions on the NR uplink and E-UTRA uplink simultaneously. In other cases, the UE may be expected to normally transmit all uplink transmissions without interruption. The UE may be configured with tdm-PatternConfig or tdm-PatternConfig2. For E-UTRA subframes designated as uplink by configuration, the UE may assume an operating state in which it can transmit one-port E-UTRA uplink. For E-UTRA subframes other than those designated as uplink by configuration (e.g., downlink and / or special and / or flexible subframes / slots / symbols), the UE may assume an operating state in which it can transmit two-port NR uplink.

[0263] The UE may indicate a capability of uplink switching (e.g., with BandCombination-UplinkTxSwitch) for a band combination for which the UE may be configured with uplink carrier aggregation. The UE may be configured with uplink switching (e.g., with the parameter uplinkTxSwitching). The UE may indicate a capability of uplink switching (e.g., with the parameter uplinkTxSwitching) for a band combination for which the UE may be configured with uplink carrier aggregation ... offsetThe UE may transmit on the uplink based on previously received DCI or based on higher layer configuration. The UE may transmit a two-port transmission on one uplink carrier and the preceding uplink transmission may be a one-port transmission on another uplink carrier. The UE may transmit a two-port transmission on one uplink carrier and the preceding uplink transmission may be a one-port transmission on another uplink carrier. The UE may transmit a two-port transmission on one uplink carrier during a switching period / gap N TX1-TX2 The UE may not be expected to transmit for the duration of the switching period / gap N of either of the two carriers. The UE may be transmitting a one-port transmission on one uplink carrier and the preceding uplink transmission may be a two-port transmission on another uplink carrier. The UE may be expected to transmit for the duration of the switching period / gap N of either of the two carriers. TX1-TX2 It cannot be expected that the UE will transmit for the duration of the

[0264] For a UE configured in switched UL transmission mode (e.g., uplinkTxSwitchingOption set to "switchedUL"), when the UE transmits a single-port transmission on one uplink carrier, and if the previous uplink transmission was a single-port transmission on another uplink carrier, then the UE shall transmit a single-port transmission on either of the two carriers for a switching period / gap N TX1-TX2 For a UE configured in dual UL transmission mode (e.g., uplinkTxSwitchingOption is set to "dualUL"), when the UE transmits a two-port transmission on one uplink carrier, and if the previous uplink transmission was a one-port transmission on the same uplink carrier, and / or the UE is in an operating state in which two-port transmission cannot be supported on the same uplink carrier, then the UE shall not be expected to transmit during switching period / gap N on either of the two carriers. TX1-TX2For a UE configured in dual UL transmission mode (e.g., uplinkTxSwitchingOption is set to "dualUL"), when the UE transmits a one-port transmission on one uplink carrier, and if the previous uplink transmission was a one-port transmission on another uplink carrier, and / or the UE is in an operating state in which two-port transmission can be supported on the same uplink carrier, the UE shall not be expected to transmit during the switching period / gap N on either of the two carriers. TX1-TX2 A UE may not be expected to transmit during a period of time that is not interrupted by a UE being scheduled and / or configured with an uplink transmission that results in simultaneous transmission on two antenna ports on one uplink carrier and any transmission on another uplink carrier. In other cases, a UE may be expected to normally transmit all uplink transmissions without interruption.

[0265] The UE may indicate a capability of uplink switching (e.g., with BandCombination-UplinkTxSwitch) for a band combination. For that band combination, the UE may be configured with a serving cell having two uplink carriers, e.g., configured with a SUL with higher layer parameter supplementaryUplink. The UE may be configured with uplink switching (e.g., with parameter uplinkTxSwitching). If the UE is configured with a T0-T offset If the UE transmits any uplink channel or signal on a different uplink than the preceding transmission opportunity based on DCI received before switching gap N or based on higher layer configuration, then the UE shall determine whether uplink switching occurs within the switching gap N TX1-TX2 where T0 is the start time of the first symbol of the transmission opportunity of the uplink channel or signal, and T offset is the preparation time for an uplink channel or signal transmission opportunity. Switching gap N TX1-TX2During this time, the UE may not be expected to transmit on either of the two uplinks. In other cases, the UE may be expected to normally transmit all uplink transmissions without interruption.

[0266] There are various emerging new consumer services that require high uplink date rates, such as HD video calls, online webcasts / sales, Augmented Reality (AR), etc., which require BMS uplink data rates of about 10 s. To boost uplink throughput and capacity for such widely applicable scenarios, it is necessary to efficiently utilize all uplink resources in multi-carrier scenarios (>2 frequency bands). In practical deployment scenarios, the network supports more than 2 bands. Therefore, efficient utilization of these UL resources can be prioritized.

[0267] However, it is difficult to implement more than 2Tx for smartphones due to increased cost, complexity, heat, power consumption, and intermodulation interference. Current commercially available smartphones support a maximum of 2Tx RF chains, so current smartphones cannot transmit on more than 2 bands simultaneously. It is difficult to implement more Tx RF chains for smartphones for the following reasons: Cost and complexity are increasing due to more Tx RF chains, power modules, etc. Size, heat and power consumption also increase dramatically when more than 2 power modules work simultaneously. More Tx RF chains also increase the number of PLLs (phase-locked loops) and LOs (local oscillators), which causes intermodulation interference and degrades downlink performance for some band combinations, and some Tx RF resources cannot be fully utilized due to power limitations or limitations of less available UL slots on TDD bands. It is expected that there will be a high proportion of smartphones in the future. This will make it very difficult for networks to fully utilize all of the available uplink resources / bands and for smartphones to increase their uplink data rates.

[0268] The extensions to operate with more than four Tx antennas can be considered to target devices such as CPE or IoT devices without size and cost constraints. The extensions for frequency selective precoding can be considered to provide most gains when the transmission includes four MIMO layers, so such gains do not apply to 2Tx smartphones. The mTRP (multiple transmit receive point) uplink enhancements are in principle applicable to all device types and provide mainly gains for cell edge performance in macrocell mTRP deployments, although uplink performance can be improved for smartphones without coverage-limited conditions.

[0269] Many operators have deployed or are planning to deploy NR on more than two frequency bands with different bandwidths, TDD / FDD duplexing, and DL / UL configurations. To boost uplink throughput and capacity for widely applicable scenarios, it is necessary to efficiently utilize all uplink resources in multi-carrier scenarios (>2 bands) where most devices are smartphones with a limited number of Tx antennas (e.g., 2Tx). Therefore, it is important to dynamically enable 2Tx switching between more than two UL bands.

[0270] In the existing technology, band configuration and UL capability of simultaneous transmission are strictly coupled. Limited by the protocol design, a UE with 2Tx may be configured with two UL bands, and thus 2Tx switching may be performed across the two configured UL bands. Semi-static RRC cell reconfiguration can be used to select / switch carriers among more than two bands. UL Tx switching between two configured bands was introduced for 2Tx UEs to improve UL data rates by allowing 2Tx to be used for UL MIMO on any one of the two bands in a switching manner. For the uplink, the network needs to configure the serving cell to comply with the UE uplink capabilities derived from the FeatureSetCombination requirements, regardless of the serving cell's state, e.g., up or down. In other words, UE uplink capabilities such as band configuration, activation, and simultaneous transmission are strictly coupled in the existing technology, e.g., the maximum number of configured bands, the maximum number of activated bands, and the maximum number of uplink transmission bands for PUSCH are equal to each other. The maximum number of PUSCH transmission bands depends on the number of simultaneous Tx RF chains equipped on the UE. Thus, limited by protocol design, a 2Tx UE can simultaneously configure up to two UL bands with / without Tx switching, which can enable activation / deactivation on the two configured UL bands. A 2Tx UE can select or switch carriers among more than two UL bands by RRC-based cell reconfiguration, which requires much longer latency.

[0271] In existing technology, switching carriers between two or more UL bands is via RRC-based cell reconfiguration, which requires long delays, e.g., about 50 ms (Note: fast cell startup / shutdown is possible within two configured UL bands). Dynamic UL 2Tx switching between two or more UL bands can enable much faster carrier switching, requiring much shorter delays, e.g., symbol level delays similar to SRS carrier switching.

[0272] Band configuration and UL capability of simultaneous transmission are preferably decoupled, e.g., maximum number of configured bands > maximum number of simultaneous transmission bands. This allows a UE with 2Tx to be configured with more than two UL bands and therefore dynamically perform Tx switching across more than two configured UL bands, e.g., four UL bands. This allows for flexible spectrum access.

[0273] Dynamic 2Tx switching between more than two bands may be based on the traffic of each band, TDD D / U (downlink symbols / uplink symbols) configuration, bandwidth, and channel conditions. Dynamic 2Tx switching between more than two bands may result in higher UL data rates, higher system spectrum utilization, and higher UL capacity for delayed combined traffic due to efficient utilization of TDD UL slots, better adaptation to channel conditions, and higher trunk efficiency.

[0274] To compare the RF complexity of 2Tx switching on more than 2 UL bands, the comparison can be made with 3Tx or 4Tx devices, i.e. devices supporting 3UL or 4UL simultaneous transmissions, although Tx switching requires some switches. The RF of these devices is much more complex than 2Tx with Tx switching. The main difference is the number of power supplies and Tx RF chains required (only 2 power supplies and Tx RF chains required for 2 simultaneous uplinks).

[0275] In 5G evolution (Release 18), flexible spectrum access (FSA) as a flexible spectrum utilization mechanism for 2Tx or 3Tx UEs is an important direction to improve uplink user-perceived throughput and network throughput. For example, the UE capabilities of configuration, activation, and simultaneous transmission can be decoupled. In this way, a UE can be configured and activated in more than two bands while utilizing one or two of those bands for simultaneous PUSCH transmission with two simultaneous Tx RF chains. Thus, FSA provides a mechanism to dynamically select a subset of carriers to be configured and switch Tx for transmission accordingly based on the traffic, TDD D / U configuration, bandwidth, and channel conditions in each band. Furthermore, a UE device capable of 2Tx switching between more than two UL bands is much less complex and costly than a UE device capable of simultaneous transmission in more than two UL bands (e.g., 3Tx or 4Tx UE), the main difference of which comes from the number of power sources.

[0276] By supporting dynamic UL Tx switching between more than two bands, FSA may result in higher UL data rates, higher system spectrum utilization, and higher UL capacity for delay-combined traffic.

[0277] Dynamic UL Tx switching between more than two bands allows efficient utilization of TDD UL slots. The network can dynamically schedule the UE on the band with wider bandwidth and / or most unscheduled RBs in a given slot. For example, for a given slot, when one of the active TDD bands / cells is downlink (D), the UE can be switched to another TDD band which is uplink (U) according to the TDD configuration to provide higher UL data rates with wider bandwidth, and when uplink slots are available on the band, the UE can be switched to the TDD band. As a result, the FSA can achieve higher UL data rates with more UL available resources.

[0278] Dynamic UL Tx switching between more than two bands allows better adaptation to channel conditions. The network can schedule UEs on bands with better channel conditions. Compared to legacy mechanisms, more UL bands are available to improve channel adaptation. For example, for cell edge users, selecting the best UL carrier and RB from more UL spectrum enabled by FSA results in better uplink coverage and higher UL system efficiency.

[0279] Dynamic UL Tx switching between two or more bands enables higher trunk efficiency. Emerging applications such as virtual reality and augmented reality impose strict latency (millisecond level) and reliability requirements. FSA can mitigate the transmission timeout problem and thus provide significant performance improvement for these applications thanks to TTI-level carrier switching and fast system load balancing. Specifically, considering that traffic arrives randomly, when a frequency band is congested with user traffic, FSA can dynamically allocate part of the traffic load to another frequency band to use unoccupied resources as much as possible.

[0280] In existing technology, a UE may be semi-statically configured with two carriers from two frequency bands for UL Tx switching. For example, a UE may receive higher layer signaling (e.g., RRC message) semi-statically configuring two carriers with two frequency bands for UL Tx switching. For example, higher layer signaling, configuring two carriers with two frequency bands for UL Tx switching may require a long time (e.g., tens of milliseconds). To enable dynamic UL Tx switching across M (e.g., M>2) frequency bands, a UE supports M Tx antennas / chains (which causes high cost and high power consumption). To enable dynamic UL Tx switching across M (e.g., M>2) frequency bands, for example, a lower layer signaling (PDCCH (e.g., DCI) in the PHY layer and / or MAC CE in the MAC layer) mechanism may be incorporated into UL Tx switching to help a 2Tx UE dynamically use one or more UL carriers with one or more bands switched among multiple bands (e.g., M bands). Based on existing technology, there are gaps to enable this functionality for 2Tx UEs, e.g., existing UL Tx switching technology is not scalable to support more than two frequency bands.

[0281] For example, if switching between any two bands out of M (M>2) constituent bands is allowed, new Tx switching scenarios (e.g., Tx switching and / or any switching of 2Tx between the same two bands) may emerge that are not supported by current standards and / or technologies. Some of these new Tx switching scenarios may not be necessary and / or may not be essential for UL capacity increase in practical deployments.

[0282] FIG. 24 illustrates an example of UL Tx switching for a 2Tx UE. As shown in the figure, based on existing technology, a UE may be configured with carrier 1 in band 1 and carrier 2 in band 2, e.g., carrier 1 may be 1Tx antenna and carrier 2 may be 2Tx antenna. The UE may use a first Tx (e.g., Tx-1 in the figure) for uplink transmission over carrier 2, and based on UL Tx switching, may use a second Tx (e.g., Tx-2 in the figure) for uplink transmission over carrier 1 and carrier 2. If the UE is configured with more than two bands, e.g., carrier 3 in band 3 and / or carrier 4 in band 4, then different possibilities may arise depending on whether carrier 3 and carrier 4 are configured to support dual stream UL transmission (e.g., can be 1Tx antenna or 2Tx antenna).

[0283] FIG. 25 illustrates an example of UL Tx switching for a 2Tx UE across more than two bands. In this example, carrier 1 and carrier 3 are configured to be capable of 1Tx antennas (e.g., supporting single-tier transmission), and carrier 2 and carrier 4 are configured to be capable of 2Tx antennas (e.g., supporting single-tier and dual-tier transmission). As shown, if no restrictions apply, the UE can switch (move / retune / reconfigure) the Tx chains / antennas of any and / or both of the M=4 bands. For example, at time T2, a grant for carrier 2 is received, which requires the UE to switch both Tx-1 and Tx-2 from band 4 to band 2. This is a new Tx switching scenario. For example, at time T3, a first grant is received for carrier 3 and a second grant is received for carrier 4, which requires the UE to switch both Tx chains (Tx-1 from band 2 to band 3, and Tx-2 from band 2 to band 4). In another example, the UE may switch Tx-2 from band 2 to band 3 and Tx-1 from band 2 to band 4. Depending on which Tx switches from which band to which band, the resulting switching gaps, and therefore the uplink transmissions, may be different. A similar scenario occurs at T4. For example, at time T5, a grant is received for carrier 4, which requires the UE to switch both Tx chains (Tx-1 from band 1 to band 4, and Tx-2 from band 2 to band 4). In this scenario, the switching of each Tx chain may require different times and result in different switching gaps. It is essential for the network to know the resulting switching gaps in order to process the received UL transmissions. This information also helps the network to more efficiently schedule uplink transmissions across the configured UL carriers.

[0284] Some necessary limitations may be necessary to avoid overly complex designs without visible gains towards manageable and scalable dynamic multi-carrier UL operation in practical scenarios. For example, it may not be necessary to support all possible combinations for UL Tx switching between configured bands and / or carriers. For example, there may be no motivation to support all two simultaneous bands from / across four configured bands, which would result in (4C2)=6 different states.

[0285] Furthermore, for new Tx switching scenarios, some restrictions in UL Tx switching may be needed. For example, whether both Tx chains can be switched at the same time and / or whether at least one of them is not switched (e.g., fixed to use a specific carrier)? For example, in some scenarios, the resulting UL transmission may be different depending on which Tx chain is switched, and thus some restrictions may be necessary to avoid uncertainties and / or overly complex designs. For example, the network may not be able to control the internal processes of all wireless devices. In these scenarios, some restrictions may be useful.

[0286] For example, in existing technology, a single switching period / gap is reported and used for one pair of bands, including a single (e.g., the same) Tx switching between the two bands. If switching between any two of the M (M>2) configured bands is allowed, new Tx switching scenarios (e.g., Tx switching and / or any switching of 2 Tx between the same two bands) may emerge, which are not supported by the current standard. New Tx switching scenarios may result in new / different switching periods, for example, depending on the UE's RF hardware of the two Tx chains. For example, if Tx switching is left to the UE implementation, the same carrier switching may result in different Tx switching (e.g., based on the UE implementation) and therefore different switching gaps, which may affect the resulting UL transmission due to puncturing.

[0287] For successful reception of UL transmissions on the network side, it is essential to address the new Tx switching scenarios so that the UE and the network have a common understanding of the corresponding switching periods in each scenario. This information allows the network to better schedule UL transmissions across the M configured bands.

[0288] Furthermore, if the UE implementation randomly switches Tx channels and either RF chains and antenna connectors at the TTI level based on scheduling commands, the UE power consumption of the UE will increase. It may be desirable to define UE behavior for new scenarios to limit dynamic Tx switching scenarios, enable switching Tx decisions, and reduce power consumption.

[0289] The embodiments propose one or more dynamic Tx switching operations, as well as RRC signaling to enable new switching scenarios within the proposed operations, so that the network can control / predict the UE's UL Tx switching possibilities (thus enhancing UL processing / scheduling). The embodiments allow the UE to decide how to map each of the two Tx chains / antennas to M (M>2) UL carriers / bands, and which Tx to use for which band in new emerging switching scenarios. The Tx chain to use / switch for each transmission may not be explicitly indicated by the network (and may remain UE implementation). The exemplary embodiments may provide some guidelines / frames that help the network and the UE have a mutual understanding of the Tx switching gaps in new switching scenarios. For example, the UE may implicitly decide and switch / use the Tx chain based on the embodiments.

[0290] In some embodiments, the network may configure multiple (e.g., two or more) paired carriers / bands (i.e., 2) of the M carriers / bands for dynamic UL Tx switching operation. For example, the network may indicate to the UE to use one pair of carriers at a time for dynamic UL Tx switching, e.g., based on activation of the carrier pair. The UE may change / switch the active carrier pair, e.g., shut down the first carrier pair and activate the second carrier pair, based on some (L1 / L2) signaling and / or timer and / or indication. The pairing mechanism may be used to limit the Tx switching scenarios and band combinations. For example, the network may have the opportunity to configure carrier / band pairs where Tx switching brings visible gains. The pairing mechanism may be scalable and may enable the network and UE to reuse the existing Tx switching framework based on one pair of (active) carriers / bands without requiring cell reconfiguration.

[0291] In some embodiments, the network may configure an anchor carrier (e.g., can be 2 Tx antennas) and multiple switched carriers across M-1 bands. The anchor carrier based mechanism in the example embodiment may extend the existing Tx switching framework to allow the UE to switch a single (e.g., same) Tx chain between M (M>2) carriers / bands by restricting the Tx switching scenarios. The network may indicate the anchor carrier to the UE at the time for dynamic UL Tx switching, e.g., based on activation of the carrier pair. The UE may change / switch the anchor carrier, e.g., stop the first anchor carrier and activate the second anchor carrier, based on some (L1 / L2) signaling and / or timer and / or indication. The anchor mechanism may be scalable and may allow more dynamic utilization of the bands configured in a systematic approach.

[0292] Some embodiments may apply to UEs configured with more than two uplink carriers from more than two frequency bands. Some embodiments may apply to UEs with more than 2Tx, e.g., 3Tx. 4Tx. Some embodiments may apply to UEs configured with UL carriers from several frequency bands that exceed UL Tx capabilities.

[0293] A 2Tx UE may be a UE that has / includes two UL Tx channels / chains / antennas (but not more). A 2Tx UE may be capable of two UL Tx antenna connectors.

[0294] A 2Tx UE may not be able to switch both Tx chains / antennas simultaneously. For example, it may take a significant amount of time / period for the UE to switch both Tx chains / antennas simultaneously. Embodiments may enable the UE to perform UL Tx switching without requiring unnecessary switching of both Tx chains / antennas simultaneously. For example, in accordance with some embodiments, the UE may not be able to switch 2Tx based on a scheduling command, but may be based on some specific switching command (e.g., via MAC-CE or specific DCI format).

[0295] The wireless device may receive one or more messages from at least one base station. The one or more messages may include one or more RRC messages (e.g., RRCSetup and / or RRCReconfiguration) and / or SIBs (e.g., SIB1). The one or more messages may configure one or more serving cells for the UE (e.g., a PCell, a PScell, a SPcell, and / or a SCell). For example, the one or more messages may include information elements and / or configuration parameters indicating the one or more serving cells.

[0296] One or more serving cells may be associated with the same Timing Advance Group (TAG). One or more serving cells may be associated with different TAGs. One or more serving cells may be associated with the same cell group (e.g., master cell group or secondary cell group). One or more serving cells may be associated with different cell groups.

[0297] A serving cell may include one or more uplink carriers, e.g., a (normal) uplink (UL or NUL) carrier, and / or a complementary uplink (SUL) carrier. In one embodiment, the UE may receive one or more messages including configuration parameters indicating multiple uplink carriers for the UE. The multiple UL carriers may be associated with / with carriers of the same serving cell (e.g., NUL and SUL) or different serving cells (e.g., UL CA and / or NR-DC and / or EN-DC and / or NE-DC).

[0298] In one embodiment, a UE may be configured with multiple bands in an uplink. For example, the multiple UL carriers may be from different frequency bands. For example, each UL carrier of the multiple UL carriers may belong to a different band. For example, a first UL carrier may belong to a first band, a second UL carrier may belong to a second band, a third UL carrier may belong to a third band, and a fourth UL carrier (if present) may belong to a fourth band. For example, a UE may be configured with at least one SUL carrier. For example, a UE may be configured with multi-carrier inter-band carrier aggregation. For example, a UE may be configured with multi-carrier dual connectivity.

[0299] The UE may have / include two UL Tx chains / antennas. The UE's UL Tx chains / antennas may not be capable of supporting UL transmissions simultaneously on two (or more) different frequency bands (e.g., having two or more different center frequencies). The UE may reconfigure / retune the Tx antennas / RF chains to support UL transmissions simultaneously on two (or more) different frequency bands. For example, the UE may move / switch the UL Tx chains / antennas from a first UL carrier in a first band to a second UL carrier in a second band.

[0300] In one embodiment, a UE may be configured with multiple uplink carriers within the same frequency band (e.g., intra-band CA). The UE's UL Tx chains / antennas may support simultaneous UL transmissions on the same frequency band (e.g., same center frequency). The UE may not need to reconfigure / retune the Tx antennas / RF chains to support simultaneous UL transmissions over carriers in the same frequency band. For example, the UE may not move / switch UL Tx chains / antennas between bands because the same UL Tx configuration may support simultaneous UL transmissions over different carriers in the same band (e.g., subject to power limitations).

[0301] A UE (e.g., having 2Tx capability with / including 2Tx chains / antennas) may be configured with three or more UL carriers (e.g., M UL carriers, M>2) from different frequency bands (e.g., M bands, M>2). For example, a first UL carrier may belong to a first band, a second UL carrier may belong to a second band, a third UL carrier may belong to a third band, and a fourth UL carrier (if present) may belong to a fourth band.

[0302] The UE may be configured with (dynamic) UL Tx switching between configured UL carriers. For example, one or more messages may indicate to the UE that UL Tx switching is configured / enabled / used for M (M>2) UL carriers (e.g., via uplinkTxSwitching per UL carrier).

[0303] The UE may be configured with one or more UL carrier "pairs" (e.g., pairs of UL carriers) from the M configured UL carriers. The UE may be configured with two or more UL carrier pairs for dynamic UL Tx switching. The UE may receive one or more messages (e.g., RRC messages and / or SIBs) indicating UL carrier pairs, each UL carrier pair including two UL carriers from the configured UL carriers. The one or more messages may include information elements and / or configuration parameters indicating UL carrier pairs from the multiple configured UL carriers.

[0304] A UL carrier pair (e.g., a UL carrier coupling, or a UL carrier twin, or a set of two UL carriers) may include two UL carriers. The two uplink carriers of a carrier pair may consist of a UL carrier. For example, a first UL carrier pair may include a first UL carrier and a second UL carrier. For example, the one or more messages may indicate:

[0305] One or more serving cells associated with the two UL carriers of the carrier pair may or may not be activated (e.g., via one or more cell activation mechanisms). For example, at least one of the one or more serving cells may be a dormant cell.

[0306] Figure 26 shows an example of UL carrier pairs configured for dynamic UL Tx switching. As shown in Figure 26, a UE (e.g., a 2Tx UE) may be configured with four UL carriers on four different bands. The UE may be configured with four UL carrier pairs. For example, UL carrier pair #1 includes UL carrier 1 and UL carrier 2. For example, UL carrier pair #2 includes UL carrier 1 and UL carrier 3. For example, UL carrier pair #3 includes UL carrier 2 and UL carrier 4. For example, UL carrier pair #4 includes UL carrier 3 and UL carrier 4.

[0307] Note that in Figure 26, it is possible to configure (4C2) = 6 carrier pairs, but the network limits the combinations by configuring 4 pairs (2 pairs are excluded and not configured). The 4 configured UL carrier pairs can be configured based on allowable / desired carrier switching scenarios.

[0308] At a given time, the UE may use one UL carrier pair, for example, based on UL Tx switching. For example, as shown in FIG. 26, the UE may use UL carrier pair #T1 during (T0, T1), UL carrier pair #T2 during (T1, T2), UL carrier pair #3 during (T2, T3), and UL carrier pair #4 after T3. The UE may switch the UL Tx chain / antenna between the two UL carriers of a pair (used pair, or active pair) during the associated time interval. The UE may switch the UL Tx chain / antenna between the two UL carriers of a pair based on the received scheduling command. For example, the UE may switch the Tx chain / antenna between UL carrier 1 and UL carrier 2 during (T0, T1) and between UL carrier 1 and UL carrier 3 during (T1, T2).

[0309] In one embodiment, one or more carrier pairs may have a UL carrier in common. These pairs may be referred to as "common pairs." For example, in FIG. 26, UL carrier pair #1 and UL carrier pair #2 have UL carrier 1 in common.

[0310] In one embodiment, each UL carrier may be exclusively configured in one UL carrier pair (e.g., UL carrier pairs may not have any UL carrier in common), e.g., a UE may not expect to receive a UL carrier configuration parameter indicating that the UL carrier belongs to more than one UL carrier pair.

[0311] In one embodiment, a "carrier pair" may be referred to as a "band pair" based on a one-to-one mapping of a UL carrier and a band.

[0312] In one embodiment, one of the two UL carriers in the UL carrier pair is capable of 1Tx (supports 1Tx / one Tx antenna connector) and the other UL carrier in the UL carrier pair is capable of 2Tx (supports 2Tx / two Tx antenna connectors). For example, the UE may transmit a single UL transmission over a first UL carrier of the UL carrier pair capable of 1Tx. For example, the UE may transmit a single UL transmission and / or a two-tier UL transmission over a second UL carrier of the UL carrier pair capable of 2Tx.

[0313] Figure 27 shows an example of signaling between a UE and a base station for carrier pair configuration. The UE may be configured with M (M>2) UL carriers. As shown in the figure, the UE may receive an RRC configuration indicating UL carrier pairs (e.g., N UL carrier pairs, N>1) (UL carrier pair #0, UL carrier pair #1, ..., UL carrier pair #N-1).

[0314] In one embodiment, each UL carrier may be configured with a UL carrier index, e.g., UplinkCarrier-Id={0, 1, ..., M-1}. For example, the RRC configuration may include a parameter indicating a UL carrier index for each configured UL carrier. The RRC configuration may include an information element for dynamic UL Tx switching, e.g., indicating N UL carrier pairs. For example, the RRC configuration may include a field indicating a first UL carrier pair with a first index (e.g., UL UplinkCarrierPair-Id=i, i=0, 1, ..., N-1) that includes a first UL carrier (e.g., UL carrier #x, x=0, 1, ..., M-1) and a second UL carrier (e.g., UL carrier #y, y=0, 1, ..., M-1, x≠y).

[0315] In one embodiment, the RRC configuration may indicate that for / in a UL carrier pair, each UL carrier supports 1TX or 2TX. For example, for a UL carrier pair #i={UL carrier #x, UL carrier #y}, the RRC configuration parameters may indicate that UL carrier #x is "carrier 1", which may be, for example, a 1Tx / 1Tx antenna connector, and UL carrier #y is "carrier 2", which may be, for example, a 2Tx / 2Tx antenna connector. In one example, the RRC message may include an information field for each UL carrier pair that explicitly indicates the Tx capability of each configured UL carrier (e.g., 1Tx or 2Tx).

[0316] In one embodiment, the UE may determine the Tx capability of each UL carrier of the UL carrier pair. For example, the UE may receive a configuration parameter indicating a UL carrier pair #i={UL carrier #x, UL carrier #y}. The configuration parameter may implicitly indicate the Tx capability of each UL carrier of the UL carrier pair, e.g., based on a rule. The rule may be based on the order of the UL carriers in the RRC field that configures / indicates the corresponding UL carrier pair. For example, the UE may determine that the first (e.g., left) UL carrier is capable of 1Tx (e.g., carrier #x is the "carrier 1" of the pair) and the second (e.g., right) UL carrier is capable of 2Tx (e.g., carrier #y is the "carrier 2" of the pair), or vice versa. In one embodiment, the rule may be based on the index of the UL carrier in the UL carrier pair. For example, the UE may determine that the UL carrier with the smaller carrier index is capable of 1Tx and the other UL carrier with the larger carrier index is capable of 2Tx, or vice versa.

[0317] In one embodiment, the Tx capability of a UL carrier may be the same for multiple UL carrier pairs to which it belongs (e.g., carrier-specific parameters). For example, UL carrier #x may be capable of 1Tx (or 2Tx) regardless of the UL carrier pair. For example, if the first UL carrier pair and the second UL carrier pair include UL carrier #x, the Tx capability of UL carrier #x is the same for both UL carrier pairs.

[0318] In one embodiment, the Tx capability of a UL carrier may differ among the UL carrier pairs to which it belongs (e.g., carrier pair specific parameters). For example, UL carrier #x may be capable of 1Tx (or 2Tx) depending on the UL carrier pair configuration. For example, if a first UL carrier pair and a second UL carrier pair include UL carrier #x, the Tx capability of UL carrier #x in the first UL carrier pair may be 1Tx, and the Tx capability of UL carrier #x in the second UL carrier pair may be 2Tx.

[0319] In one embodiment, for each configured UL carrier, the field / parameter may indicate the UL carrier pair to which this UL carrier belongs, e.g., a bitmap with a maximum size of N=(M_select2), where each bit indicates whether the corresponding pair is defined using the configured UL carrier, e.g., bit#0=0 means that UL carrier pair#0 does not include this UL carrier, bit#1=0 means that UL carrier pair#1 does not include this UL carrier, and bit#2=1 means that UL carrier pair#2 includes this UL carrier. In one embodiment, for each carrier, there are a maximum of M-1 pairs for UL Tx switching, e.g., the sum of the bitmap may be less than or equal to M-1. In one embodiment, for each carrier, there is one pair for UL Tx switching, e.g., the sum of the bitmap may be equal to 1.

[0320] In one embodiment, a one-to-one mapping may be defined between configured UL carriers. For example, the RRC may indicate whether each UL carrier is 1Tx capable or 2Tx capable. The RRC may indicate a one-to-one mapping between 1Tx UL carriers and 2Tx UL carriers. For example, each one-to-one mapping may indicate a UL carrier pair. In one embodiment, the mapping may be explicitly indicated by an RRC field / parameter. In one embodiment, the mapping may be implicit, for example, based on a common configuration between two UL carriers and / or based on a UL carrier index of the UL carrier. For example, the RRC may tag each 1Tx UL carrier with an index from a first set and each 2Tx UL carrier with an index from a second set, and a mapping may be defined between the indexes of the first set and the indexes of the second set. For example, {UL carrier #1, UL carrier #3} may be configured as a 1Tx carrier and tagged with index {1,2}, and {UL carrier #2, UL carrier #4} may be configured as a 2Tx carrier and tagged with index {1,2}. The UE may determine a first UL carrier pair as {UL carrier #1, UL carrier #2} and a second UL carrier pair as {UL carrier #3, UL carrier #4} (e.g., index 1:1 and index 2:2).

[0321] In one embodiment, when a 2Tx carrier is switched, the corresponding 1Tx carrier is also switched based on the configuration of the UL carrier pair.

[0322] As shown in Figure 27, the UE may receive an indication of activation of a UL carrier pair from a base station. For example, the UE may receive DCI and / or MAC-CE (e.g., L1 / L2 signaling over MAC-CE or a specific DCI format indicating a switching / activation command) indicating activation of a UL carrier pair. For example, a downlink signal may indicate that a UL carrier pair #i = {UL carrier #x, UL carrier #y} has been activated.

[0323] When a UL carrier pair is activated, the UE may use two uplink carriers of the activated UL carrier pair for UL transmission, for example, based on UL Tx switching. For example, the UE's UL transmission (e.g., excluding SRS) may be limited to the two UL carriers of the activated UL carrier pair (e.g., UL carrier #x and UL carrier #y). In one embodiment, the UE may not expect to receive scheduling commands (e.g., UL grants for PUSCH and / or PUCCH and / or PRACH and / or one or more reference signals) for UL carriers outside / not belonging to the active UL carrier pair. In one embodiment, the UE may not monitor a core set / search space associated with a UL carrier not belonging to the active UL carrier pair. In one embodiment, the UE may stop semi-static UL transmission (e.g., configured grant type 1 and / or configured grant type 2) on UL carriers (e.g., excluding SRS) not belonging to the active UL carrier pair.

[0324] At a given time, a single UL carrier pair may be activated. For example, the UE may activate the first UL carrier pair, e.g., in response to an indication of activation of the first UL carrier pair. In one embodiment, the RRC configuration may include a field / parameter indicating a default / initial / primary UL carrier pair (e.g., firstActiveCarrierPair and / or defaultPair and / or initialPair). For example, the default / initial UL carrier pair may be activated upon receiving an RRC configuration, where the RRC configuration may indicate that UL Tx switching is configured. For example, the two UL carriers of the first UL carrier pair may be associated with the active serving cell.

[0325] In one embodiment, the UE may receive an indication to change / switch the UL carrier pair, for example, via DCI / MAC-CE. Upon receiving the UL carrier pair switching indication, the UE may deactivate the first UL carrier pair (which is active) and activate the second UL carrier pair. For example, the DCI / MAC-CE containing the UL carrier pair switching command may indicate the second UL carrier pair. For example, one UL carrier pair out of N configured carrier pairs may be active at a given time.

[0326] In one embodiment, the UE may decide to activate a default / initial UL carrier pair in response to PCell / PScell ​​activation.

[0327] In one embodiment, the UE may determine to activate the UL carrier pair in response to activation of one or more serving cells associated with at least one UL carrier of the UL carrier pair.

[0328] In one embodiment, the UE may decide to switch to a default / initial UL carrier pair in response to an outage of one or more serving cells associated with at least one UL carrier of the active UL carrier pair.

[0329] In one embodiment, the UE may decide to switch to a default / initial UL carrier pair in response to expiration of a timer. For example, the RRC message may configure a UL carrier pair switching timer and / or indicate the duration of the timer. The timer may help avoid excessive UL carrier pair changes when not necessary (e.g., not enough UL grants are received based on Tx switching). For example, the timer may be reset in response to receiving a scheduling command (e.g., a UL grant) for any of the UL carriers of the active UL carrier pair.

[0330] The embodiments allow for using L1 / L2 and / or automatic decision (e.g., based on timers) to change the pair of configured UL carriers instead of RRC signaling, thus significantly reducing dynamic Tx switching delay. According to the embodiments, the UE can perform dynamic UL Tx switching between two UL carriers of an active UL carrier pair using existing switching framework. For example, the UE can switch one Tx between carrier 1 and carrier 2 in / of an active carrier pair based on a scheduling command. The RRC signaling can indicate UL Tx switching parameters per UL carrier pair. The RRC signaling can indicate which carriers in the carrier pair are capable of 1Tx and which are capable of 2Tx. For example, the RRC configuration can indicate the first UL carrier as carrier 1 (e.g., capable of 1Tx) and the second uplink carrier as carrier 2 (e.g., capable of 2Tx) for each configured UL carrier pair. The UE may use one Tx chain / antenna for UL transmission over the second carrier (i.e., carrier 2 of the pair) and / or switch another Tx chain / antenna between the first and second UL carriers of the pair. The UE may apply respective Tx switching gaps based on the two UL carriers of the active UL carrier pair and based on the respective band combinations.

[0331] When switching UL carrier pairs, common band switching may be allowed / defined to reduce start-up delays. For example, one of the carriers may be common between the new pair and the old pair (before and after switching). For example, the first carrier of the new pair and the second carrier of the old pair may belong to the same / common frequency band. In one embodiment, the common carrier and / or carrier associated with the common band may be capable of 1Tx (i.e., "carrier 1"). In one embodiment, the common carrier and / or carrier associated with the common band may be capable of 2Tx (i.e., "carrier 2").

[0332] FIG. 28 shows an example of UL carrier pairs configured for dynamic UL Tx switching. In this example, carrier pair switching based on common band and / or common carrier is illustrated. As shown in the figure, each carrier pair switching involves a single carrier switching, e.g., carrier 2 switching to carrier 4 on T1 (carrier 1 / band 1 is common) and carrier 1 switching to carrier 3 on T2 (carrier 4 / band 4 is common). The figure proposes a method to assign Tx chains / antennas to UL carriers based on a pairing mechanism. As shown in the figure, Tx-1 is used for the 2Tx carrier (carrier that can be two Tx antenna connectors) of the respective UL carrier pair, and Tx-2 (shown in grey) is switched between the 1Tx carrier and the 2Tx carrier of the UL carrier pair.

[0333] In one embodiment, the wireless device may receive one or more messages including configuration parameters indicating multiple uplink carriers for the UE. The multiple UL carriers may be associated with / with carriers of the same serving cell (e.g., NUL and SUL) or different serving cells (e.g., UL CA and / or NR-DC and / or EN-DC and / or NE-DC).

[0334] In one embodiment, a UE may be configured with multiple bands in an uplink. For example, the multiple UL carriers may be from different frequency bands. For example, each UL carrier of the multiple UL carriers may belong to a different band. For example, a first UL carrier may belong to a first band, a second UL carrier may belong to a second band, a third UL carrier may belong to a third band, and a fourth UL carrier (if present) may belong to a fourth band. For example, a UE may be configured with at least one SUL carrier. For example, a UE may be configured with multi-carrier inter-band carrier aggregation. For example, a UE may be configured with multi-carrier dual connectivity.

[0335] The UE may be configured with (dynamic) UL Tx switching between configured UL carriers. For example, one or more messages may indicate to the UE that UL Tx switching is configured / enabled / used for M (M>2) UL carriers (e.g., via uplinkTxSwitching per UL carrier).

[0336] The UE may receive one or more messages (e.g., RRC messages and / or SIBs) indicating one or more "anchor" UL carriers. The anchor UL carrier may be a UL carrier that can be two transmit antenna connectors (e.g., 2Tx carrier). The UE (e.g., a 2Tx UE, or a UE with two Tx chains / antennas) may use one (e.g., the first) Tx chain / antenna for the anchor UL carrier. For example, the first Tx chain / antenna may not be switched between UL carriers in dynamic UL Tx switching. For example, the first Tx chain / antenna may be fixed / tuned / configured to the anchor UL carrier frequency.

[0337] In one embodiment, the anchor UL carrier may be a UL carrier that can be one transmit antenna connector (e.g., 1Tx carrier). A UE (e.g., a 2Tx UE, or a UE with two Tx chains / antennas) may use one (e.g., the first) Tx chain / antenna for the anchor UL carrier. For example, the first Tx chain / antenna may be switched between UL carriers in dynamic UL Tx switching.

[0338] In one embodiment, the first Tx chain may be fixed / tuned / configured to the UL carrier of the frequency band in which the anchor carrier resides.

[0339] In one embodiment, the "anchor" UL carrier may be referred to as a default UL carrier, or an active UL carrier, or a common UL carrier, or a primary UL carrier, or the like.

[0340] In one embodiment, the anchor UL carrier may be activated. For example, the UE may receive downlink signaling (e.g., RRC and / or DCI and / or MAC-CE signaling) indicating that the first UL carrier is activated as the anchor / active / common / default UL carrier.

[0341] The anchor UL carrier may be associated with a set / group of second UL carriers. For example, the one or more messages may include configuration parameters indicating one or more sets / groups of second UL carriers. In one embodiment, the group of second UL carriers may include one or more UL carriers that may be one transmit antenna connector (e.g., 1Tx carrier). A UE (e.g., a 2Tx UE, or a UE with two Tx chains / antennas) may use one (e.g., a first) Tx chain / antenna for the anchor UL carrier and may move / switch another (e.g., a second) Tx chain / antenna between the second UL carrier and / or the group of anchor UL carriers. For example, the second Tx chain / antenna may be switched based on dynamic Tx switching across UL carriers including the anchor UL carrier and one or more second UL carriers associated with the anchor UL carrier.

[0342] In one embodiment, the group of second UL carriers may include one or more UL carriers that may be two transmit antenna connectors (e.g., 2Tx carriers). The UE (e.g., a 2Tx UE, or a UE with two Tx chains / antennas) may move / switch the two (e.g., first and second) Tx chains / antennas between the group of second UL carriers and / or anchor UL carriers. For example, the two Tx chains / antennas may be switched based on dynamic Tx switching across one or more second UL carriers associated with the anchor UL carrier. For example, one of the two (e.g., first) Tx chains / antennas may be switched based on dynamic Tx switching across UL carriers including the anchor UL carrier and one or more second UL carriers associated with the anchor UL carrier.

[0343] In one embodiment, one or more second UL carriers associated with the anchor UL carrier may be activated in response to activation of the first / anchor UL carrier (e.g., may be used for dynamic UL Tx switching). In one embodiment, the anchor UL carrier may be activated. In one embodiment, at least one second UL carrier of the one or more second UL carriers associated with the first / anchor UL carrier may be activated. The first / anchor UL carrier and the at least one second UL carrier may be used for dynamic UL Tx switching.

[0344] Throughout this disclosure, when two or more UL carriers are used for dynamic UL Tx switching, the UE may move one or more Tx chains / antennas across the two or more UL carriers based on the dynamic UL Tx switching. For example, the UE may transmit UL transmissions using two or more UL carriers based on the dynamic UL Tx switching, e.g., based on scheduling commands and / or received UL grants and / or semi-static UL grants. In one embodiment, the dynamic UL Tx switching may be responsive to a TDD configuration and / or slot format indicating uplink "U" slots / symbols / subframes of the UL carriers.

[0345] In one embodiment, the RRC message may configure one or more sets / groups / lists of UL carriers. For example, the set of UL carriers may include an anchor UL carrier and one or more second UL carriers (e.g., switched UL carriers). The UE may activate and / or determine to activate a first set of UL carriers among the set of one or more UL carriers. For example, the UE may receive an indication of activation of the first UL carrier set (or the first UL carrier set). The UE may use the first set of UL carriers for dynamic UL Tx switching. For example, the UE may transmit UL transmissions using the first set of UL carriers based on dynamic UL Tx switching, e.g., based on a scheduling command and / or a received UL grant and / or a semi-static UL grant.

[0346] In one embodiment, the UE may be configured with multiple anchor UL carriers, e.g., a set / group / list of anchor UL carriers. The set / group / list of anchor UL carriers may include UL carriers that may be 2Tx antenna connectors. The UE may receive a downlink signal (e.g., RRC / DCI / MAC-CE, e.g., a specific DCI format including MAC-CE or activation / switching command) that includes an indication to change / switch the anchor UL carrier. For example, the UE may decide to switch / change the anchor UL carrier in response to expiration of a first timer, e.g., a UL Tx switching timer.

[0347] For example, the RRC message may indicate the value / duration of the UL Tx switching timer. The first time scale for the first / anchor carrier switching may be larger than the second time scale for the second carrier switching (e.g., based on a scheduling command). This may help to reduce the power consumption and delay / gap required for Tx switching (e.g., 2Tx switching scenario). The network may use the UL Tx switching timer to manage the time scale. For example, the anchor carrier may not change while the UL Tx switching timer is running. For example, the second carrier may change / switch between sets of UL carriers while the UL Tx switching timer is running. For example, at the expiration of the timer, the anchor UL carrier may switch / change between sets / lists of anchor UL carriers.

[0348] The UE may activate a first anchor UL carrier. The first anchor UL carrier may be associated with a PCell / PScell. The first anchor UL carrier may be associated with a cell having a smallest cell index. The first anchor UL carrier may have a smallest UL carrier index among the anchor UL carriers and / or the multiple configured UL carriers. In one embodiment, the first anchor UL carrier may be one Tx antenna connector. In one embodiment, the first anchor UL carrier may be two Tx antenna connectors.

[0349] The UE may switch / change the anchor / active UL carrier from the first anchor UL carrier to the second anchor UL carrier. For example, the UE may stop the first anchor UL carrier and / or start the second anchor UL carrier. For example, downlink signaling (e.g., RRC / DCI / MAC-CE) may indicate the second anchor UL carrier.

[0350] Each anchor UL carrier may be configured with an associated set of secondary UL carriers. For example, a set of secondary UL carriers may be one Tx antenna connector. In one embodiment, a set of secondary UL carriers may be two Tx antenna connectors.

[0351] In one embodiment, the UE may activate a first set of second UL carriers associated with a first anchor UL carrier. The UE may switch / change from the first set of second UL carriers to a second set of second UL carriers. For example, the UE may stop the first set of second UL carriers and / or activate the second set of second UL carriers. For example, the second set of second UL carriers may be associated with a second anchor UL carrier. For example, the second anchor UL carrier may be activated.

[0352] The UE may switch / change an active set of UL carriers including the active anchor UL carrier and / or the anchor UL carrier and a set of second UL carriers associated with the anchor UL carrier. For example, the UE may change / switch from a first anchor UL carrier to a second anchor UL carrier as the active anchor UL carrier. For example, the UE may change / switch from a first set of UL carriers to a second set of UL carriers as the active set of UL carriers. In one embodiment, the switching may be in response to receiving an indication of switching via downlink signaling (e.g., RRC and / or MAC-CE and / or DCI). In one embodiment, the switching may be in response to expiration of a first timer, e.g., a carrier / UL Tx switching timer.

[0353] The UE may use the active anchor UL carrier and one or more active secondary UL carriers associated with the active anchor UL carrier to transmit UL transmissions based on the dynamic UL Tx switching. The UE may use an active set of UL carriers to transmit UL transmissions based on the dynamic UL Tx switching.

[0354] FIG. 29 shows an example of dynamic UL Tx switching across four UL carriers in four different bands. In this example, a UE is configured with a set of four UL carriers, UL carrier 1, UL carrier 2, UL carrier 3, and UL carrier 4. The UE may determine that UL carrier 4 is the anchor UL carrier of the set. For example, UL carrier 4 may be configured via RRC signaling as the anchor UL carrier. The UE may determine that UL carrier 1 and UL carrier 2 and UL carrier 3 are second UL carriers associated with the anchor UL carrier (UL carrier 4). For example, the RRC signaling may indicate the association. The UE may activate anchor UL carrier 4. The UE may activate the set of UL carriers that includes / associates with UL carrier 4.

[0355] In the example shown in FIG. 29, the UE uses one Tx chain / antenna (Tx-1) for UL transmission over UL carrier 4 (anchor UL carrier) and / or switches the other Tx chain / antenna (Tx-2) among / across a set of UL carriers (UL carrier 1 and UL carrier 2 and UL carrier 3 and UL carrier 4). For example, at time T0, the UE may transmit one UL transmission using Tx-1 over UL carrier 4 and / or transmit one UL transmission using Tx-2 over UL carrier 3. The UE may receive a UL grant for UL carrier 4 at T1. The UL grant may include a two-tiered UL grant. For example, the UE may switch Tx-2 to UL carrier 4. The UE transmits a two-tiered UL transmission over UL carrier 4 using Tx-1 and Tx-2. The UE may switch Tx-2 to UL carrier 1 at T2, e.g., for a single-tier UL transmission via UL carrier 1 and / or in response to a TDD configuration and / or slot format indicating uplink "U" slots / symbols / subframes of UL carrier 1. The UE may receive a UL grant for UL carrier 4 at T3. The UL grant may include a two-tier UL grant. For example, the UE may switch Tx-2 to UL carrier 4. The UE transmits a two-tier UL transmission via UL carrier 4 using Tx-1 and Tx-2.

[0356] In one example, the UE may receive an indication (e.g., a switching command) to switch the anchor UL carrier from carrier 4 to carrier 2. For example, the UE may receive a MAC-CE / DCI including the indication. The UE may use one Tx chain / antenna (Tx-1) for UL transmission over UL carrier 2 (anchor UL carrier) and / or switch the other Tx chain / antenna (Tx-2) among / across the set of UL carriers (UL carrier 1 and UL carrier 2 and UL carrier 3 and UL carrier 4).

[0357] The UE may expect to be scheduled with two-port / two-tier UL transmission to the (active) anchor UL carrier.

[0358] In one embodiment, the RRC configuration of the anchor UL carrier or UL carrier pair may be responsive to UE capabilities. For example, the UE may transmit capability information including a field indicating that the UE is not capable of simultaneous switching of two Tx chains / antennas. For example, the UE may not anticipate simultaneous switching of both Tx chains / antennas, which may not be based on a scheduling command, but may be based on a specific switching / activation command indicated by the MAC-CE and / or a specific DCI format, for example, for UL carrier pair switching and / or anchor UL carrier switching / activation.

[0359] Throughout this disclosure, "carrier" may be replaced by "band", e.g., UL band pair, and / or anchor band, and / or band switching, etc.

[0360] In one embodiment, the UE may receive an RRC message including a configuration parameter indicating each configured UL carrier as either Carrier 1 (capable of 1Tx) or Carrier 2 (capable of 2Tx). The network may configure two sets / groups of UL carriers, e.g., a first group of UL carriers (capable of 1Tx) as Carrier 1 and a second group of UL carriers (capable of 2Tx) as Carrier 2. In one example, the first half / portion of configured UL carriers including a first half / portion of carrier indexes having a lower value may include the first group, and the second half / portion of configured UL carriers including a second half / portion of carrier indexes having a higher value may include the second group, or vice versa.

[0361] In one embodiment, which carriers are allowed to be switched between may be predefined / configured. For example, switching between carriers of the same / opposite Tx capabilities may be allowed. In one embodiment, at a given time, a UE is not expected to be performing dynamic Tx switching using two carriers with the same Tx capabilities, e.g., one carrier supporting 1Tx and the other supporting 2Tx. In one embodiment, if at a given time, a UE uses two carriers supporting 2Tx, the UE is not expected to transmit two port transmissions on two UL carriers simultaneously.

[0362] FIG. 30 illustrates an example of dynamic UL Tx switching according to an embodiment. In this example, received RRC signaling may indicate that UL Carrier 2 and UL Carrier 3 may be two UL Tx antenna connectors and UL Carrier 1 may be one UL Tx antenna connector. In this example, the UE switches both Tx chains / antennas from UL Carrier 2 to UL Carrier 3 at time T1. For example, the UE may transmit a two-port UL transmission using both Tx chains / antennas via UL Carrier 3. A previous UL transmission may be another two-port UL transmission using both Tx chains / antennas via UL Carrier 2. Respective switching gaps for switching both Tx associated with band combinations including Band 2 and Band 3 may be applied during which the UE may not expect to transmit on the (two) UL carriers.

[0363] 30, UL Carrier 1 may be an anchor UL carrier. UL Carrier 2 and UL Carrier 3 may be secondary UL carriers associated with UL Carrier 1.

[0364] Figure 31 shows an example of dynamic UL Tx switching. In this example, the UE cannot perform dual UL transmission. This embodiment may be referred to as a switched UL transmission mode (e.g., TDM). For example, received RRC signaling may indicate / configure UL Carrier 2 and UL Carrier 3 as switched UL carriers.

[0365] The wireless device may receive one or more messages including configuration parameters for one or more cells. The wireless device may receive one or more Radio Resource Control (RRC) messages indicating multiple uplink carrier pairs, each uplink carrier pair including two uplink carriers to which the transmit antenna may switch. The wireless device may switch the first transmit antenna from a first uplink carrier of the first uplink carrier pair to a second uplink carrier of the first uplink carrier pair. The first uplink carrier pair may be selected from the multiple uplink carrier pairs. The wireless device may transmit an uplink transmission using the first transmit antenna over the second uplink carrier.

[0366] The one or more RRC messages may further indicate that uplink transmission switching is configured for the wireless device using an uplink carrier pair of the multiple uplink carrier pairs. The wireless device may select a first uplink carrier pair from the multiple uplink carrier pairs. The first uplink carrier may be configured in a first frequency band. The second uplink carrier may be configured in a second frequency band. The first uplink carrier and the second uplink carrier may be configured for dual connectivity. The first uplink carrier and the second uplink carrier may be configured for carrier aggregation. The carrier aggregation may be inter-band carrier aggregation. One of the first uplink carrier and the second uplink carrier may be configured for complementary uplink. The transmitter of the wireless device may include a first transmit antenna and a second transmit antenna. The number of transmit antennas of the wireless device may be two. The first transmit antenna may be switched between the first uplink carrier and the second uplink carrier. The second transmit antenna may be used for uplink transmission via the first uplink carrier. The switching may be responsive to receiving a scheduling command for the second uplink carrier. The scheduling command may indicate a one-port uplink transmission.

[0367] The wireless device may switch the first transmit antenna from the second uplink carrier to the first uplink carrier. For example, switching the first transmit antenna from the second uplink carrier to the first uplink carrier includes (re)configuring the first transmit antenna to be used for transmissions scheduled over the first uplink carrier. For example, switching the first transmit antenna from the second uplink carrier to the first uplink carrier includes (re)configuring the first transmit antenna to not be used for the second uplink carrier. The switching may be responsive to receiving a second scheduling command for the first uplink carrier. The second scheduling command may indicate a two-port uplink transmission. The wireless device may transmit a two-port (e.g., dual) uplink transmission over the first uplink carrier using the first transmit antenna and the second transmit antenna. The wireless device may support a two-port (e.g., dual) uplink transmission using the first transmit antenna and the second transmit antenna. The wireless device may receive configuration parameters of the cell group. The cell group may include a first uplink carrier and a second uplink carrier indicating that two-port (e.g., dual) uplink transmission is enabled via the first uplink carrier. The wireless device may select a first uplink carrier pair from among the multiple uplink carrier pairs based on receiving an indication of activation of the first uplink carrier pair. One or more RRC messages may include an indication of activation of the first uplink carrier. The wireless device may receive a downlink signal including an indication of activation of the first uplink carrier. The downlink signal may be downlink control information (DCI) based on a first format. The downlink signal may be a medium access control control element (MAC-CE) including an indication of activation of the first uplink carrier. The indication of activation of the first uplink carrier may be responsive to expiration of a timer at a higher layer.

[0368] The one or more RRC messages may further indicate to the wireless device a configuration of a plurality of cells including a plurality of uplink carriers, including two uplink carriers of a first uplink carrier pair. Each uplink carrier of the plurality of uplink carriers may be associated with a respective frequency band. For each uplink carrier pair, the one or more RRC messages may include respective parameters for uplink transmission switching. The respective parameters for each uplink carrier pair for uplink transmission switching may include an indication that one of the two uplink carriers of the respective uplink carrier pair may be one transmit antenna connector and another one of the two uplink carriers may be two transmit antenna connectors. The respective parameters for each uplink carrier pair for uplink transmission switching may include an indication of an uplink transmission switching option (e.g., including option 1 and / or option 2 in an exemplary embodiment). The uplink transmission switching option may include switched uplink (e.g., option 1 in an exemplary embodiment) or dual uplink (e.g., option 2 in an exemplary embodiment). The parameters for uplink transmission switching may include an indication of a position of an uplink transmission switching period. The wireless device may transmit wireless device capability information indicating a supported band combination including a first frequency band in which the first uplink carrier resides and a second frequency band in which the second uplink carrier resides. The capability information may further indicate an uplink transmission switching period associated with switching the first transmit antenna from the first uplink carrier to the second uplink carrier.

[0369] The wireless device may receive one or more Radio Resource Control (RRC) messages indicating multiple uplink carrier pairs, each uplink carrier pair including two uplink carriers for uplink transmit antenna switching. The wireless device may determine to switch one of the uplink transmit antennas between the two uplink carriers of a first uplink carrier pair from among the multiple uplink carrier pairs. The wireless device may transmit an uplink transmission using the uplink transmit antenna via the first uplink carrier pair.

[0370] The wireless device may receive one or more radio resource control (RRC) messages indicating a configuration of uplink carriers, each uplink carrier associated with a respective frequency band, first parameters for uplink transmission switching using a first carrier pair including a first uplink carrier and a second uplink carrier of the uplink carriers, and second parameters for uplink transmission switching using a second carrier pair including a third uplink carrier and a fourth uplink carrier of the uplink carriers. The wireless device may determine to switch between the first uplink carrier and the second uplink carrier in response to activation of the first carrier pair. The wireless device may transmit uplink transmissions via the first uplink carrier and the second uplink carrier based on the first parameters.

[0371] The wireless device may receive one or more radio resource control (RRC) messages indicating a plurality of uplink carriers including a first uplink carrier associated with a first frequency band capable of transmitting using two transmit antennas and two or more second uplink carriers associated with a second frequency band different from the first frequency band capable of transmitting using one transmit antenna. The wireless device may switch the uplink transmit antenna between two uplink carriers of the plurality of uplink carriers. The wireless device may transmit an uplink transmission over the plurality of uplink carriers based on the switching.

[0372] The wireless device may transmit a two-port uplink transmission via a first uplink carrier and using the transmit antenna and the second transmit antenna. The wireless device may switch the uplink transmit antenna from the first uplink carrier to a second uplink carrier from the two or more second uplink carriers. The wireless device may transmit a one-port uplink transmission via the second uplink carrier and using the transmit antenna. The wireless device may transmit a one-port uplink transmission via the first uplink carrier and using the second transmit antenna. The one or more RRC messages may further indicate two or more first uplink carriers, including a first uplink carrier that can be transmitted using two transmit antennas. The wireless device may switch the second transmit antenna from the first uplink carrier to a third uplink carrier, the third uplink carrier being selected from the two or more first uplink carriers. The wireless device may transmit a two-port uplink transmission via the third uplink carrier and using the transmit antenna and the second transmit antenna. The switching may be responsive to an indication of activation of the third uplink carrier. The wireless device may receive a second RRC message including a parameter indicating that the third uplink carrier has been activated. The second RRC message may indicate that the first uplink carrier has been deactivated. The wireless device may receive a downlink signal including an indication of activation. The downlink signal may be downlink control information (DCI) based on the first format. The downlink signal may be a medium access control element (MAC-CE) including a transport block indicating the activation. The indication may be in response to expiration of a timer at a higher layer.

Claims

1. A wireless device, one or more processors; Memory to store instructions and Equipped with The instructions, when executed by the one or more processors, receiving a radio resource control (RRC) reconfiguration or setup message including configuration parameters for at least one cell including a plurality of uplink carriers, the configuration parameters including: uplink switching using three or more uplink bands, wherein each uplink carrier of the plurality of uplink carriers is within a respective one of the three or more uplink bands; A plurality of uplink band pairs from the three or more uplink bands for the uplink switching, wherein the configuration parameters include, for each uplink band pair of the plurality of uplink band pairs, Uplink switching based on dual uplink, or Uplink switching based on switched uplink Multiple uplink band pairs, including individual parameters indicating whether they are configured with and based on a first uplink band pair of the plurality of uplink band pairs configured with uplink switching based on the dual uplink; a first uplink transmission on a first uplink band of the first uplink band pair; and a second uplink transmission on a second uplink band of the first uplink band pair. Sending and The wireless device causes the wireless device to perform the above.

2. The wireless device of claim 1, further comprising simultaneously transmitting the first uplink transmission and the second uplink transmission based on the first uplink band pair being configured with uplink switching based on the dual uplink.

3. The wireless device of claim 1, wherein the first uplink transmission is a first one-port physical uplink shared channel (PUSCH) transmission on a first uplink carrier of the plurality of uplink carriers on the first uplink band.

4. The wireless device of claim 1, further comprising transmitting capability information of the wireless device indicating a combination of supported bands including the first uplink band and the second uplink band.

5. A base station, one or more processors; Memory to store instructions and Equipped with The instructions, when executed by the one or more processors, transmitting a radio resource control (RRC) reconfiguration or setup message including configuration parameters of at least one cell including a plurality of uplink carriers, the configuration parameters including: uplink switching using three or more uplink bands, wherein each uplink carrier of the plurality of uplink carriers is within a respective one of the three or more uplink bands; A plurality of uplink band pairs from the three or more uplink bands for the uplink switching, wherein the configuration parameters include, for each uplink band pair of the plurality of uplink band pairs, Uplink switching based on dual uplink, or Uplink switching based on switched uplink Multiple uplink band pairs, including individual parameters indicating whether they are configured with and based on a first uplink band pair of the plurality of uplink band pairs configured with uplink switching based on the dual uplink; a first uplink transmission on a first uplink band of the first uplink band pair; and a second uplink transmission on a second uplink band of the first uplink band pair. Receiving and The base station causes the base station to perform the above.

6. The base station described in claim 5, further comprising simultaneously receiving the first uplink transmission and the second uplink transmission based on the first uplink band pair being configured with uplink switching based on the dual uplink.

7. A base station as described in claim 5, wherein the first uplink transmission is a first one-port physical uplink shared channel (PUSCH) transmission on a first uplink carrier of the plurality of uplink carriers on the first uplink band.

8. A non-transitory computer-readable medium comprising instructions that, when executed by one or more processors of a wireless device, receiving a radio resource control (RRC) reconfiguration or setup message including configuration parameters for at least one cell including a plurality of uplink carriers, the configuration parameters including: uplink switching using three or more uplink bands, wherein each uplink carrier of the plurality of uplink carriers is within a respective one of the three or more uplink bands; A plurality of uplink band pairs from the three or more uplink bands for the uplink switching, wherein the configuration parameters include, for each uplink band pair of the plurality of uplink band pairs, Uplink switching based on dual uplink, or Uplink switching based on switched uplink Multiple uplink band pairs, including individual parameters indicating whether they are configured with and based on a first uplink band pair of the plurality of uplink band pairs configured with uplink switching based on the dual uplink; a first uplink transmission on a first uplink band of the first uplink band pair; and a second uplink transmission on a second uplink band of the first uplink band pair. Sending and a non-transitory computer-readable medium for causing the wireless device to perform the steps of:

9. The non-transitory computer-readable medium of claim 8, further comprising simultaneously transmitting the first uplink transmission and the second uplink transmission based on the first uplink band pair being configured with uplink switching based on the dual uplink.

10. The non-transitory computer-readable medium of claim 8, wherein the first uplink transmission is a first one-port physical uplink shared channel (PUSCH) transmission on a first uplink carrier of the plurality of uplink carriers on the first uplink band.

11. The non-transitory computer-readable medium of claim 8, further comprising transmitting capability information of the wireless device indicating a supported band combination including the first uplink band and the second uplink band.

12. The wireless device of claim 1, wherein the configuration parameters further indicate at least one uplink carrier of the plurality of uplink carriers associated with each cell of the at least one cell.

13. The wireless device of claim 1, wherein the configuration parameters further indicate, for each uplink carrier of the plurality of uplink carriers, an individual frequency domain location within a frequency range of an individual band of the three or more uplink bands.

14. The wireless device of claim 1, wherein the second uplink transmission is a second one-port physical uplink shared channel (PUSCH) transmission on a second uplink carrier of the plurality of uplink carriers on the second uplink band.

15. The wireless device of claim 1, wherein the second uplink transmission is a second two-port physical uplink shared channel (PUSCH) transmission on a second uplink carrier of the plurality of uplink carriers on the second uplink band.

16. The base station of claim 5, wherein the configuration parameters further indicate at least one uplink carrier of the plurality of uplink carriers associated with each cell of the at least one cell.

17. The base station described in claim 5, wherein the configuration parameters further indicate, for each uplink carrier of the plurality of uplink carriers, an individual frequency domain location within a frequency range of an individual band of the three or more uplink bands.

18. The base station described in claim 5, wherein the second uplink transmission is a second one-port physical uplink shared channel (PUSCH) transmission on a second uplink carrier of the plurality of uplink carriers on the second uplink band.

19. The base station described in claim 5, wherein the second uplink transmission is a second two-port physical uplink shared channel (PUSCH) transmission on a second uplink carrier of the plurality of uplink carriers on the second uplink band.

Images