PATENT DOCUMENT

Publication Number: US-12028766-B2
Application Number: US-202117437803-A
Country: US
Kind Code: B2

Title: Secondary cell activation and change procedures

Abstract:
Aspects are presented herein of apparatuses, systems, and methods for secondary cell group (SCG) addition. A wireless device may establish communication with a first base station that is comprised a master cell group (MCG). The wireless device may receive signaling from the first base station configuring a second base station in a secondary cell group (SCG). The wireless device may establish communication with the second base station based on the signaling received from the first base station. At a first time, the wireless device may set the second base station in a deactivated state based on the signaling from the first base station configuring the second base station or establishing communication with the second base station. At a later time, the wireless device may set the second base station in an activated state and communicate with the first base station and the second base station.

Claims:
What is claimed is: 
     
       1. An apparatus, comprising:
 at least one processor, configured to cause a wireless device to:
 establish communication with a first base station, wherein the first base station is comprised in a master cell group (MCG); 
 receive signaling from the first base station configuring a second base station, wherein the second base station is comprised in a secondary cell group (SCG); 
 establish communication with the second base station based on the signaling received from the first base station; 
 at a first time, set the second base station in a deactivated state, based on the signaling from the first base station configuring the second base station or establishing communication with the second base station; 
 at a later time, set the second base station in an activated state; and 
 communicate with a base station in the MCG and the second base station in response to setting the second base station in the activated state. 
 
 
     
     
       2. The apparatus of  claim 1 , wherein the signaling from the first base station configuring the second base station includes a random access channel (RACH) configuration, wherein said establishing communication with the second base station is performed using a RACH procedure using the RACH configuration. 
     
     
       3. The apparatus of  claim 1 , wherein said establishing communication with the second base station is performed while the second base station is set to the activated state. 
     
     
       4. The apparatus of  claim 3 , wherein setting the second base station in the deactivated state is performed based on the signaling from the first base station indicating the deactivated state. 
     
     
       5. The apparatus of  claim 3 , wherein setting the second base station in the deactivated state is performed based on an indication of the deactivated state during a random access procedure. 
     
     
       6. The apparatus of  claim 5 , wherein setting the second base station in the deactivated state is indicated in MsgB of a two step random access procedure. 
     
     
       7. The apparatus of  claim 5 , wherein setting the second base station in the deactivated state is indicated in Msg2 or Msg4 of a four step contention based random access procedure. 
     
     
       8. An apparatus, comprising:
 at least one processor configured to cause a first base station to:
 establish communication with a wireless device, wherein the first base station is comprised in a master cell group (MCG) for the wireless device; 
 perform a secondary cell group (SCG) addition procedure with a second base station; 
 provide RRC signaling to the wireless device regarding the second base station; 
 receive a response from the wireless device in response to the RRC signaling, wherein the response indicates completion of the SCG addition; and 
 in response to receiving the response from the wireless device, provide a SCG addition or change completion indication to the second base station. 
 
 
     
     
       9. The apparatus of  claim 8 , wherein the RRC signaling indicates a deactivated state for the second base station. 
     
     
       10. The apparatus of  claim 8 , wherein the RRC signaling indicates a random access channel (RACH) configuration usable by the wireless device to perform a RACH procedure with the second base station. 
     
     
       11. The apparatus of  claim 8 , wherein the at least one processor is further configured to cause the first base station to:
 after providing the SCG addition completion indication to the second base station, provide an SCG activation message to the wireless device, wherein the SCG activation message indicates a random access channel (RACH) resource for performing a RACH procedure with the second base station. 
 
     
     
       12. The apparatus of  claim 8 , wherein the RRC signaling does not include a random access channel (RACH) configuration. 
     
     
       13. A wireless device, comprising:
 wireless communication circuitry; and 
 at least one processor coupled to the wireless communication circuitry, configured to cause the wireless device to:
 establish communication with a first base station, wherein the first base station is comprised in a master cell group (MCG); 
 receive signaling from the first base station configuring a second base station, wherein the second base station is comprised in a secondary cell group (SCG), and wherein the signaling from the first base station indicates a deactivated state for the second base station; 
 at a first time, set the second base station in the deactivated state based on the signaling from the first base station configuring the second base station; 
 at a later time, set the second base station in an activated state and establishing communication with the second base station based on the signaling received from the first base station; and 
 communicate with a base station in the MCG and the second base station in response to setting the second base station in the activated state. 
 
 
     
     
       14. The wireless device of  claim 13 , wherein said setting the second base station in the activated state and said communicating with the base station in the MCG and the second base station is performed in response to data for transmission by the wireless device, wherein said communicating with the base station in the MCG and the second base station includes transmitting the data. 
     
     
       15. The wireless device of  claim 13 , wherein said setting the second base station in the activated state and said communicating with base station in the MCG and the second base station is performed in response to receiving an activation message from the base station in the MCG or the second base station. 
     
     
       16. The wireless device of  claim 15 , wherein the activation message indicates a resource for performing a random access channel (RACH) procedure, wherein said establishing communication with the second base station comprises performing the RACH procedure using the resource. 
     
     
       17. The wireless device of  claim 13 , wherein the signaling from the first base station configuring the second base station includes a random access channel (RACH) configuration, wherein said establishing communication with the second base station is performed using a RACH procedure using the RACH configuration. 
     
     
       18. The wireless device of  claim 13 , wherein the signaling from the first base station configuring the second base station does not include a random access channel (RACH) configuration. 
     
     
       19. The wireless device of  claim 18 , wherein said establishing communication with the second base station and said communicating with the second base station does not include performing a RACH procedure. 
     
     
       20. The wireless device of  claim 19 , wherein said communicating with the second base station includes using a predetermined timing advance value.

Description:
PRIORITY CLAIM INFORMATION 
     This application is a U.S. National Stage application of International Application No. PCT/CN2021/071291, filed Jan. 12, 2021, titled “Secondary Cell Activation and Change Procedures”, which is hereby incorporated by reference in its entirety. 
     TECHNICAL FIELD 
     The present application relates to wireless devices, including apparatuses, systems, and methods for secondary cell activation and change procedures. 
     BACKGROUND 
     Wireless communication systems are rapidly growing in usage. Wireless devices, particularly wireless user equipment devices (UEs), have become widespread. Additionally, there are a variety of applications (or apps) hosted on UEs that per or depend on wireless communication, such as applications that provide messaging, email, browsing, video streaming, short video, voice streaming, real-time gaming, or various other online services. 
     Increased reliability in these communication systems are desirable. 
     SUMMARY 
     Aspects are presented herein of apparatuses, systems, and methods for secondary cell group (SCG) addition. 
     A wireless device may establish communication with a first base station that is comprised in a master cell group (MCG). The wireless device may receive signaling from the first base station configuring a second base station in a secondary cell group (SCG). The wireless device may establish communication with the second base station based on the signaling received from the first base station. At a first time, the wireless device may set the second base station in a deactivated state based on the signaling from the first base station configuring the second base station or establishing communication with the second base station. At a later time, the wireless device may set the second base station in an activated state and communicate with the first base station and the second base station. 
     A wireless device may establish communication with a first base station comprised in a master cell group (MCG). The wireless device may receive signaling from the first base station configuring a second base station in a secondary cell group (SCG). The signaling from the base station may indicate a deactivated state for the second base station. At a first time, the wireless device may set the second base station in the deactivated state based on the signaling from the first base station configuring the second base station. At a later time, the wireless device may set the second base station in an activated state and establish communication with the second base station based on the signaling received from the first base station. Accordingly, the wireless device may communicate with the first base station and the second base station in response to setting the second base station in the activated state. 
     In some aspects, a non-transitory memory medium may include program instructions executable by a UE that, when executed, cause the UE to perform at least a portion or all of the above operations. In some aspects, a method performed by the UE may include the UE performing the above operations. In some aspects, a method performed by a base station or network element may include the base station or network element performing corresponding operations. 
     This Summary is intended to provide a brief overview of some of the subject matter described in this document. Accordingly, it will be appreciated that the above-described features are merely examples and should not be construed to narrow the scope or spirit of the subject matter described herein in any way. Other features, aspects, and advantages of the subject matter described herein will become apparent from the following Detailed Description, Figures, and Claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       A better understanding of the disclosed aspects can be obtained when the following detailed description is considered in conjunction with the following drawings, in which: 
         FIG.  1    illustrates an example wireless communication system, according to some aspects; 
         FIG.  2    illustrates a base station (BS) in communication with a user equipment (UE) device, according to some aspects; 
         FIG.  3    illustrates an example block diagram of a UE, according to some aspects; 
         FIG.  4    illustrates an example block diagram of a BS, according to some aspects; 
         FIG.  5    illustrates an example block diagram of cellular communication circuitry, according to some aspects, 
         FIGS.  6  and  7    illustrate examples of a 5G NR base station (gNB), according to some aspects; 
         FIG.  8    illustrates an exemplary wireless network communication with a UE, according to some aspects; 
         FIG.  9    is a diagram illustrating art example cell coverage scenario for macro and smell cells, according to some aspects; and 
         FIGS.  10 - 16    are flow chart diagrams illustrating example methods for secondary cell group activation and change procedures, according to some aspects. 
     
    
    
     While the invention is susceptible to various modifications and alternative forms, specific aspects thereof are shown by way of example in the drawings and are herein described in detail. It should be understood, however, that the drawings and detailed description thereto are not intended to limit the invention to the particular form disclosed, but on the contrary, the intention is to cover all modifications, equivalents and alternatives falling within the spirit and scope of the present invention as defined by the appended claims. 
     DETAILED DESCRIPTION OF THE ASPECTS 
     Acronyms 
     The following acronyms are used in the present Patent Application:
         UE: User Equipment   BS: Base Station   ENB: eNodeB (Base Station)   LTE: Long Term Evolution   UNITS: Universal Mobile Telecommunications System   RAT: Radio Access Technology   RAN: Radio Access Network   E-UTRAN: Evolved UNITS Terrestrial RAN   CN: Core Network   EPC: Evolved Packet Core   MME: Mobile Management Entity   HSS: Home Subscriber Server   SGW: Serving Gateway   PS: Packet-Switched   CS: Circuit-Switched   EPS: Evolved Packet-Switched System   RRC: Radio Resource Control   IE: Information Element   QoS: Quality of Service   QoE: Quality of Experience   TFT: Traffic Flow Template   RSVP: Resource ReSerVation Protocol   API: Application programming interface       

     Terms 
     The following is a glossary of terms used in the present application: 
     Memory Medium—Any of various types of memory devices or storage devices. The term “memory medium” is intended to include an installation medium, e.g., a CD-ROM, floppy disks  104 , or tape device; a computer system memory or random access memory such as DRAM, DDR RAM, SRAM, EDO RAM, Rambus RAM, etc.; a non-volatile memory such as a Flash, magnetic media, e.g., a hard drive, or optical storage; registers, or other similar types of memory elements, etc. The memory medium may comprise other types of memory as well or combinations thereof. In addition, the memory medium may be located in a first computer in which the programs are executed, or may be located in a second different computer which connects to the first computer over a network, such as the Internet. In the latter instance, the second computer may provide program instructions to the first computer for execution. The term “memory medium” may include two or more memory mediums which may reside in different locations, e.g., in different computers that are connected over a network. 
     Computer System—any of various types of computing or processing systems, including a personal computer system (PC), mainframe computer system, workstation, network appliance, Internet appliance, personal digital assistant (PDA), television system, grid computing system, or other device or combinations of devices. In general, the term “computer system” can be broadly defined to encompass any device (or combination of devices) having at least one processor that executes instructions from a memory medium. 
     User Equipment (UE) (or “UE Device”)—any of various types of computer systems or devices that are mobile or portable and that perform wireless communications. Examples of UE devices include mobile telephones or smart phones, tablet computers, portable gaming devices, wearable devices to (e.g., smart watch, smart glasses), laptops, PDAs, portable Internet devices, music players, data storage devices, other handheld devices, automobiles and/or motor vehicles, unmanned aerial vehicles (UAVs) (e.g., drones), UAV controllers (UACs), etc. In general, the term “UE” or “UE device” can be broadly defined to encompass any electronic, computing, and/or telecommunications device (or combination of devices) which is easily transported by a user and capable of wireless communication. 
     Processing Element—refers to various elements or combinations of elements that are capable of performing a function in a device, such as a user equipment or a cellular network device. Processing elements may include, for example processors and associated memory, portions or circuits of individual processor cores, entire processor cores, processor arrays, circuits such as an ASIC (Application Specific Integrated Circuit), programmable hardware elements such as a field programmable gate array (FPGA), as well any of various combinations of the above. 
       FIGS.  1  and  2   —Communication System 
       FIG.  1    illustrates a simplified example wireless communication system, according to some aspects. It is noted that the system of  FIG.  1    is merely one example of a possible system, and that features of this disclosure may be implemented in any of various systems, as desired. 
     As shown, the example wireless communication system includes a base station  102  which communicates over a transmission medium with one or more user devices  106 A,  106 B, etc., through  106 N. Each of the user devices may be referred to herein as a “user equipment” (UE). Thus, the user devices  106  are referred to as UEs or UE devices. 
     The base station (BS)  102  may be a base transceiver station (BTS) or cell site (a “cellular base station”), and may include hardware that enables wireless communication with the UEs  106 A through  106 N. 
     The communication area (or coverage area) of the base station may be referred to as a “cell.” The base station  102  and the UEs  106  may be configured to communicate over the transmission medium using any of various radio access technologies (RATs), also referred to as wireless communication technologies, or telecommunication standards, such as GSM, UMTS (associated with, for example, WCDMA or TD-SCDMA air interfaces), LTE, LTE-Advanced (LTE-A), 5G new radio (5G NR), 6G, HSPA, 3GPP2 CDMA2000 (e.g., 1×RTT, 1×EV-DO, HRPD, eHRPD), etc. Note that if the base station  102  is implemented in the context of LTE, it may alternately be referred to as an ‘eNodeB’ or ‘eNB’. Note that if the base station  102  is implemented in the context of 5G NR, it may alternately be referred to as ‘gNodeB’ or ‘gNB’. 
     As shown, the base station  102  may also be equipped to communicate with a network  100  (e.g., a core network of a cellular service provider, a telecommunication network such as a public switched telephone network (PSTN), and/or the Internet, among various possibilities). Thus, the base station  102  may facilitate communication between the user devices and/or between the user devices and the network  100 . In particular, the cellular base station  102  may provide UEs  106  with various telecommunication capabilities, such as voice, SMS and/or data services. 
     Base station  102  and other similar base stations operating according to the same or a different cellular communication standard may thus be provided as a network of cells, which may provide continuous or nearly continuous overlapping service to UEs  106 A-N and similar devices over a geographic area via one or more cellular communication standards. 
     Thus, while base station  102  may act as a “serving cell” for UEs  106 A-N as illustrated in  FIG.  1   , each UE  106  may also be capable of receiving signals from (and possibly within communication range of) one or more other cells (which might be provided by other base stations  102 B-N), which may be referred to as “neighboring cells”. Such cells may also be capable of facilitating communication between user devices and/or between user devices and the network  100 . Such cells may include “macro” cells, “micro” cells, “pico” cells, and/or cells which provide any of various other granularities of service area size. Other configurations are also possible. 
     In some aspects, base station  102  may be a next generation base station, e.g., a 5G New Radio (5G NR) base station, or “gNB”. In some aspects, a gNB may be connected to a legacy evolved packet core (EPC) network and/or to a NR core (NRC) network. In addition, a gNB cell may include one or more transition and reception points (TRPs). In addition, a UE capable of operating according to 5G NR may be connected to one or more TRPS within one or more gNBs. 
     Note that a UE  106  may be capable of communicating using multiple wireless communication standards. For example, the UE  106  may be configured to communicate using a wireless networking (e.g., Wi-Fi) and/or peer-to-peer wireless communication protocol (e.g., Bluetooth, Wi-Fi peer-to-peer, etc.) in addition to at least one cellular communication protocol (e.g., GSM, UMTS (associated with, for example, WCDMA or TD-SCDMA air interfaces), LTE, LTE-A, 5G NR, HSPA, 3GPP2 CDMA2000 (e.g., 1×RTT, 1×EV-DO, HRPD, eHRPD), etc.). The UE  106  may also or alternatively be configured to communicate using one or more global navigational satellite systems (GNSS, e.g., GPS or GLONASS) one or more mobile television broadcasting standards (e.g., ATSC-M/H), and/or any other wireless communication protocol, if desired. Other combinations of wireless communication standards (including more than two wireless communication standards) are also possible. 
       FIG.  2    illustrates user equipment  106  (e.g., one of the devices  106 A through  106 N) in communication with a base station  102 , according to some aspects. The UE  106  may be a device with cellular communication capability such as a mobile phone, a hand-held device, a computer or a tablet, or virtually any type of wireless device. 
     The UE  106  may include a processor that is configured to execute program instructions stored in memory. The UE  106  may perform any of the method aspects described herein by executing such stored instructions. Alternatively, or in addition, the UE  106  may include a programmable hardware element such as an FPGA (field-programmable gate array) that is configured to perform any of the method aspects described herein, or any portion of any of the method aspects described herein. 
     The UE  106  may include one or more antennas for communicating using one or more wireless communication protocols or technologies. In some aspects, the UE  106  may be configured to communicate using, for example, CDMA2000 (1×RTT/1×EV-DO/HRPD/eHRPD) or LTE using a single shared radio and/or GSM or LTE using the single shared radio. The shared radio may couple to a single antenna, or may couple to multiple antennas (e.g., for multiple-input, multiple-output or “MIMO”) for performing wireless communications. In general, a radio may include any combination of a baseband processor, analog RF signal processing circuitry (e.g., including filters, mixers, oscillators, amplifiers, etc.), or digital processing circuitry (e.g., for digital modulation as well as other digital processing). Similarly, the radio may implement one or more receive and transmit chains using the aforementioned hardware. For example, the UE  106  may share one or more parts of a receive and/or transmit chain between multiple wireless communication technologies, such as those discussed above. 
     In some aspects, the UE  106  may include any number of antennas and may be configured to use the antennas to transmit and/or receive directional wireless signals (e.g., beams). Similarly, the BS  102  may also include any number of antennas and may be configured to use the antennas to transmit and/or receive directional wireless signals (e.g., beams). To receive and/or transmit such directional signals, the antennas of the UE  106  and/or BS  102  may be configured to apply different “weight” to different antennas. The process of applying these different weights may be referred to as “precoding”. 
     In some aspects, the UE  106  may include separate transmit and/or receive chains (e.g., including separate antennas and other radio components) for each wireless communication protocol with which it is configured to communicate. As a further possibility, the UE  106  may include one or more radios which are shared between multiple wireless communication protocols, and one or more radios which are used exclusively by a single wireless communication protocol. For example, the UE  106  might include a shared radio for communicating using either of LTE or 5G NR (or LTE or 1×RTT or LTE or GSM), and separate radios for communicating using each of Wi-Fi and Bluetooth. Other configurations are also possible. 
       FIG.  3   —Block Diagram of a LTE 
       FIG.  3    illustrates an example simplified block diagram of a communication device  106 , according to some aspects. It is noted that the block diagram of the communication device of  FIG.  3    is only one example of a possible communication device. According to aspects, communication device  106  may be a user equipment (UE) device, a mobile device or mobile station, a wireless device or wireless station, a desktop computer or computing device, a mobile computing device (e.g., a laptop, notebook, or portable computing device), a tablet and/or a combination of devices, among other devices. As shown, the communication device  106  may include a set of components  300  configured to perform core functions. For example, this set of components may be implemented as a system on chip (SOC), which may include portions for various purposes. Alternatively, this set of components  300  may be implemented as separate components or groups of components for the various purposes. The set of components  300  may be coupled (e.g., communicatively; directly or indirectly) to various other circuits of the communication device  106 . 
     For example, the communication device  106  may include various types of memory (e.g., including NAND flash  310 ), an input/output interface such as connector I/F  320  (e.g., for connecting to a computer system; dock; charging station; input devices, such as a microphone, camera, keyboard; output devices, such as speakers; etc.), the display  360 , which may be integrated with or external to the communication device  106 , and cellular communication circuitry  330  such as for 5G NR, LTE, GSM, etc., and short to medium range wireless communication circuitry  329  (e.g., Bluetooth™ and WLAN circuitry). In some aspects, communication device  106  may include wired communication circuitry (not shown), such as a network interface card, e.g., for Ethernet. 
     The cellular communication circuitry  330  may couple (e.g., communicatively; directly or indirectly) to one or more antennas, such as antennas  335  and  336  as shown. The short to medium range wireless communication circuitry  329  may also couple (e.g., communicatively; directly or indirectly) to one or more antennas, such as antennas  337  and  338  as shown. Alternatively, the short to medium range wireless communication circuitry  329  may couple (e.g., communicatively; directly or indirectly) to the antennas  335  and  336  in addition to, or instead of, coupling (e.g., communicatively; directly or indirectly) to the antennas  337  and  338 . The short to medium range wireless communication circuitry  329  and/or cellular communication circuitry  330  may include multiple receive chains and/or multiple transmit chains for receiving and/or transmitting multiple spatial streams, such as in a multiple-input multiple output (MIMO) configuration. 
     In some aspects, as further described below, cellular communication circuitry  330  may include dedicated receive chains (including and/or coupled to, e.g., communicatively, directly or indirectly, dedicated processors and/or radios) for multiple RATs (e.g., a first receive chain for LTE and a second receive chain for 5G NR). In addition, in some aspects, cellular communication circuitry  330  may include a single transmit chain that may be switched between radios dedicated to specific RATs. For example, a first radio may be dedicated to a first RAT, e.g., LTE, and may be in communication with a dedicated receive chain and a transmit chain shared with an additional radio, e.g., a second radio that may be dedicated to a second RAT, e.g., 5G NR, and may be in communication with a dedicated receive chain and the shared transmit chain. 
     The communication device  106  may also include and/or be configured for use with one or more user interface elements. The user interface elements may include any of various elements, such as display  360  (which may be a touchscreen display), a keyboard (which may be a discrete keyboard or may be implemented as part of a touchscreen display), a mouse, a microphone and/or speakers, one or more cameras, one or more buttons, and/or any of various other elements capable of providing information to a user and/or receiving or interpreting user input. 
     The communication device  106  may further include one or more smart cards  345  that include SIM (Subscriber Identity Module) functionality, such as one or more UICC(s) (Universal Integrated Circuit Card(s)) cards  345 . 
     As shown, the SOC  300  may include processor(s)  302 , which may execute program instructions for the communication device  106  and display circuitry  304 , which may perform graphics processing and provide display signals to the display  360 . The processor(s)  302  may also be coupled to memory management unit (MMU)  340 , which may be configured to receive addresses from the processor(s)  302  and translate those addresses to locations in memory (e.g., memory  306 , read only memory (ROM)  350 , NAND flash memory  310 ) and/or to other circuits or devices, such as the display circuitry  304 , short range wireless communication circuitry  229 , cellular communication circuitry  330 , connector I/F  320 , and/or display  360 . The MMU  340  may be configured to perform memory protection and page table translation or set up. In some aspects, the MMU  340  may be included as a portion of the processor(s)  302 . 
     As noted above, the communication device  106  may be configured to communicate using wireless and/or wired communication circuitry. The communication device  106  may be configured to transmit a request to attach to a first network node operating according to the first RAT and transmit an indication that the wireless device is capable of maintaining substantially concurrent connections with the first network node and a second network node that operates according to the second RAT. The wireless device may also be configured transmit a request to attach to the second network node. The request may include an indication that the wireless device is capable of maintaining substantially concurrent connections with the first and second network nodes. Further, the wireless device may be configured to receive an indication that dual connectivity (DC) with the first and second network nodes has been established. 
     As described herein, the communication device  106  may include hardware and software components for implementing features for using multiplexing to perform transmissions according to multiple radio access technologies in the same frequency carrier and/or multiple frequency carriers), as well as the various other techniques described herein. The processor  302  of the communication device  106  may be configured to implement part or all of the features described herein, e.g., by executing program instructions stored on a memory medium (e.g., a non-transitory computer-readable memory medium). Alternatively (or in addition), processor  302  may be configured as a programmable hardware element, such as an FPGA (Field Programmable Gate Array), or as an ASIC (Application Specific Integrated Circuit). Alternatively (or in addition) the processor  302  of the communication device  106 , in conjunction with one or more of the other components  300 ,  304 ,  306 ,  310 ,  320 ,  329 ,  330 ,  340 ,  345 ,  350 ,  360  may be configured to implement part or all of the features described herein. 
     In addition, as described herein, processor  302  may include one or more processing elements. Thus, processor  302  may include one or more integrated circuits (ICs) that are configured to perform the functions of processor  302 . In addition, each integrated circuit may include circuitry (e.g., first circuitry, second circuitry, etc.) configured to perform the functions of processor(s)  302 . 
     Further, as described herein, cellular communication circuitry  330  and short range wireless communication circuitry  329  may each include one or more processing elements and/or processors. In other words, one or more processing elements or processors may be included in cellular communication circuitry  330  and, similarly, one or more processing elements or processors may be included in short range wireless communication circuitry  329 . Thus, cellular communication circuitry  330  may include one or more integrated circuits (ICs) that are configured to perform the functions of cellular communication circuitry  330 . In addition, each integrated circuit may include circuitry (e.g., first circuitry, second circuitry, etc.) configured to perform the functions of cellular communication circuitry  330 . Similarly, the short range wireless communication circuitry  329  may include one or more ICs that are configured to perform the functions of short range wireless communication circuitry  329 . In addition, each integrated circuit may include circuitry (e.g., first circuitry, second circuitry, etc.) configured to perform the functions of short range wireless communication circuitry  329 . 
       FIG.  4   —Block Diagram of a Base Station 
       FIG.  4    illustrates an example block diagram of a base station  102 , according to some aspects, it is noted that the base station of  FIG.  4    is merely one example of a possible base station. As shown, the base station  102  may include processor(s)  404  which may execute program instructions for the base station  102 . The processor(s)  404  may also be coupled to memory management unit (MMU)  440 , which may be configured to receive addresses from the processor(s)  404  and translate those addresses to locations in memory (e.g., memory  460  and read only memory (RUM)  450 ) or to other circuits or devices. 
     The base station  102  may include at least one network port  470 . The network port  470  may be configured to couple to a telephone network and provide a plurality of devices, such as UE devices  106 , access to the telephone network as described above in  FIGS.  1  and  2   . 
     The network port  470  (or an additional network port) may also or alternatively be configured to couple to a cellular network, e.g., a core network of a cellular service provider. The core network may provide mobility related services and/or other services to a plurality of devices, such as UE devices  106 . In some cases, the network port  470  may couple to a telephone network via the core network, and/or the core network may provide a telephone network (e.g., among other UE devices serviced by the cellular service provider). 
     In some aspects, base station  102  may be a next generation base station, e.g., a 5G New Radio (5G NR) base station, of “gNB”. In such aspects, base station  102  may be connected to a legacy evolved packet core (EPC) network and/or to a NR core (NRC) network. In addition, base station  102  may be considered a 5G NR cell and may include one or more transition and reception points (TRPs). In addition, a UE capable of operating according to 5G NR may be connected to one or more TRPs within one or more gNBs. 
     The base station  102  may include at least one antenna  434 , and possibly multiple antennas. The radio  430  and at least one antenna  434  may be configured to operate as a wireless transceiver and may be further configured to communicate with UE devices  106 . The antenna  434  may communicate with the radio  430  via communication chain  432 . Communication chain  432  may be a receive chain, a transmit chain or both. The radio  430  may be configured to communicate via various wireless communication standards, including, but not limited to, 5G NR, LTE, LTE-A, GSM, UMTS, CDMA2000, Wi-Fi, etc. 
     The base station  102  may be configured to communicate wirelessly using multiple wireless communication standards. In some instances, the base station  102  may include multiple radios, which may enable the base station  102  to communicate according to multiple wireless communication technologies. For example, as one possibility, the base station  102  may include an LTE radio for performing communication according to LTE as well as a 5G NR radio for performing communication according to 5G NR. In such a case, the base station  102  may be capable of operating as both an LTE base station and a 5G NR base station. As another possibility, the base station  102  may include a multi-mode radio which is capable of performing communications according to any of multiple wireless communication technologies (e.g., 5G NR and Wi-Fi, LTE and Wi-Fi, LTE and UMTS, LTE and CDMA2000, UMTS and GSM, etc.). 
     As described further subsequently herein, the BS  102  may include hardware and software components for implementing or supporting implementation of features described herein. The processor  404  of the base station  102  may be configured to implement or support implementation of part or all of the methods described herein, e.g., by executing program instructions stored on a memory medium (e.g., a non-transitory computer-readable memory medium). Alternatively, the processor  404  may be configured as a programmable hardware element, such as an FPGA (Field Programmable Gate Array), or as an ASIC (Application Specific integrated Circuit), or a combination thereof. Alternatively (or in addition) the processor  404  of the BS  102 , in conjunction with one or more of the other components  430 ,  432 ,  434 ,  440 ,  450 ,  460 ,  470  may be configured to implement or support implementation of part or all of the features described herein. 
     In addition, as described herein, processor(s)  404  may include one or more processing elements. Thus, processor(s)  404  may include one or more integrated circuits (ICs) that are configured to perform the functions of processor(s)  404 . In addition, each integrated circuit may include circuitry (e.g., first circuitry, second circuitry, etc.) configured to perform the functions of processor(s)  404 . 
     Further, as described herein, radio  430  may include one or more processing elements. Thus, radio  430  may include one or more integrated circuits (ICs) that are configured to perform the functions of radio  430 . In addition, each integrated circuit may include circuitry (e.g., first circuitry, second circuitry, etc.) configured to perform the functions of radio  430 . 
       FIG.  5   —Block Diagram of Cellular Communication Circuitry 
       FIG.  5    illustrates an example simplified block diagram of cellular communication circuitry, according to some aspects. It is noted that the block diagram of the cellular communication circuitry of  FIG.  5    is only one example of a possible cellular communication circuit; other circuits, such as circuits including or coupled to sufficient antennas for different RATs to perform uplink activities using separate antennas, are also possible. According, to aspects, cellular communication circuitry  330  may be included in a communication device, such as communication device  106  described above. As noted above, communication device  106  may be a user equipment (UE) device, a mobile device or mobile station, a wireless device or wireless station, a desktop computer or computing device, a mobile computing device (e.g., a laptop, notebook, or portable computing device), a tablet and/or a combination of devices, among other devices. 
     The cellular communication circuitry  330  may couple (e.g., communicatively; directly or indirectly) to one or more antennas, such as antennas  335   a - b  and  336  as shown (in  FIG.  3   ). In some aspects, cellular communication circuitry  330  may include dedicated receive chains (including and/or coupled to, e.g., communicatively, directly or indirectly, dedicated processors and/or radios) for multiple RATs (e.g., a first receive chain for LTE and a second receive chain for 5G NR). For example, as shown in  FIG.  5   , cellular communication circuitry  330  may include a modem  510  and a modem  520 . Modem  510  may be configured for communications according to a first RAT, e.g., such as LTE or LTE-A, and modem  520  may be configured for communications according to a second RAT, e.g., such as 5G NR. 
     As shown, modem  510  may include one or more processors  512  and a memory  516  in communication with processors  512 . Modem  510  may be in communication with a radio frequency (RF) front end  530 . RF front end  530  may include circuitry for transmitting and receiving radio signals. For example, RF front end  530  may include receive circuitry (RX)  532  and transmit circuitry (TX)  534 . In some aspects, receive circuitry  532  may be in communication with downlink (DL) front end  550  which may include circuitry for receiving radio signals via antenna  335   a.    
     Similarly, modem  520  may include one or more processors  522  and a memory  526  in communication with processors  522 . Modem  520  may be in communication with an RF front end  540 . RF front end  540  may include circuitry for transmitting and receiving radio signals. For example, RF front end  540  may include receive circuitry  542  and transmit circuitry  544 . In some aspects, receive circuitry  542  may be in communication with DL front end  560 , which may include circuitry for receiving radio signals via antenna  335   b.    
     In some aspects, a switch  570  may couple transmit circuitry  534  to uplink (UL) front end  572 . In addition, switch  570  may couple transmit circuitry  544  to UL front end  572 . UL front end  572  may include circuitry for transmitting radio signals via antenna  336 . Thus, when cellular communication circuitry  330  receives instructions to transmit according to the first RAT (e.g., as supported via modem  510 ), switch  570  may be switched to a first state that allows modem  510  to transmit signals according to the first RAT (e.g., via a transmit chain that includes transmit circuitry  534  and UL front end  572 ). Similarly, when cellular communication circuitry  330  receives instructions to transmit according to the second RAT (e.g., as supported via modem  520 ), switch  570  may be switched to a second state that allows modem  520  to transmit signals according to the second RAT (e.g., via a transmit chain that includes transmit circuitry  544  and UL from end  572 ). 
     In some aspects, the cellular communication circuitry  330  may be configured to transmit, via the first modem while the switch is in the first state, a request to attach to a first network node operating according to the first RAT and transmit, via the first modem while the switch is in a first state, an indication that the wireless device is capable of maintaining substantially concurrent connections with the first network node and a second network node that operates according to the second RAT. The wireless device may also be configured transmit, via the second radio while the switch is in a second state, a request to attach to the second network node. The request may include an indication that the wireless device is capable of maintaining substantially concurrent connections with the first and second network nodes. Further, the wireless device may be configured to receive, via the first radio, an indication that dual connectivity with the first and second network nodes has been established. 
     As described herein, the modem  510  may include hardware and software components for implementing features for using multiplexing to perform transmissions according to multiple radio access technologies in the same frequency carrier, as well as the various other techniques described herein. The processors  512  may be configured to implement part or all of the features described herein, e.g., by executing program instructions stored on a memory medium (e.g., a non-transitory computer-readable memory medium). Alternatively (or in addition), processor  512  may be configured as a programmable hardware element, such as an FPGA (Field Programmable Gate Array), or as an ASIC (Application Specific Integrated Circuit). Alternatively (or in addition) the processor  512 , in conjunction with one or more of the other components  530 ,  532 ,  534 ,  550 ,  570 ,  572 ,  335  and  336  may be configured to implement part or all of the features described herein. 
     In some aspects, processor(s)  512 ,  522 , etc. may be configured to implement or support implementation of part or all of the methods described herein, e.g., by executing program instructions stored on a memory medium (e.g., a non-transitory computer-readable memory medium). Alternatively, the processor(s)  512 ,  522 , etc. may be configured as a programmable hardware element, such as an FPGA, or as an ASIC or a combination thereof. In addition, as described herein, processor(s)  512 ,  522 , etc. may include one or more processing elements. Thus, processor(s)  512 ,  522 , etc. may include one or more integrated circuits (ICs) that are configured to perform the functions of processor(s)  512 ,  522 , etc. In addition, each integrated circuit may include circuitry (e.g., first circuitry, second circuitry, etc.) configured to perform the functions of processor(s)  512 ,  522 , etc. 
     As described herein, the modern  520  modem  520  may include hardware and software components for implementing features for using multiplexing to perform transmissions according to multiple radio access technologies in the same frequency carrier, as well as the various other techniques described herein. The processors  522  may be configured to implement part or all of the features described herein, e.g., by executing program instructions stored on a memory medium (e.g., a non-transitory computer-readable memory medium). Alternatively (or in addition), processor  522  may be configured as a programmable hardware element, such as an FPGA (Field Programmable Gate Array), or as an ASIC (Application Specific Integrated Circuit). Alternatively (or in addition) the processor  522 , in conjunction with one or more of the other components  540 ,  542 ,  544 ,  550 ,  570 ,  572 ,  335  and  336  may be configured to implement part or all of the features described herein. 
       FIGS.  6 - 7   —5G NR Architecture 
     In some implementations, filth generation (5G) wireless communication will initially be deployed concurrently with other wireless communication standards (e.g., LTE). For example, whereas  FIG.  6    illustrates a possible standalone (SA) implementation of a next generation core (NGC) network  606  and 5G NR base station (e.g., gNB  604 ), dual connectivity between LTE and 5G new radio (5G NR or NR), such as in accordance with the exemplary morn-standalone (NSA) architecture illustrated in  FIG.  7   , has been specified as part of the initial deployment of NR. Thus, as illustrated in  FIG.  7   , evolved packet core (EPC) network  600  may continue to communicate with current LTE base stations (e.g., eNB  602 ). In addition, eNB  602  may be in communication with a 5G NR base station (e.g., gNB  604 ) and may pass data between the EPC network  600  and gNB  604 . In some instances, the gNB  604  may also have at least a user plane reference point with EPC network  600 . Thus, EPC network  600  may be used (or reused) and gNB  604  may serve as extra capacity for UEs, e.g., for providing increased downlink throughput to UEs. In other words, LTE may be used for control plane signaling and NR may be used for user plane signaling. Thus, LTE may be used to establish connections to the network and NR may be used for data services. As will be appreciated, numerous other non-standalone architecture variants are possible. 
       FIG.  8   —Wireless Communication System 
       FIG.  6    illustrates an example simplified portion of a wireless communication system. The UE  106  may be in communication with a wireless network, e.g., a radio access network (RAN), which may include one or more base stations (BS)  102  and may provide connection to a core network (CN)  100 , such as an evolved packet core (EPC). The base station  102  may be an eNodeB and/or gNB (e.g., a 5G or NR base station) or other type of base station. The UE  106  may communicate in a wireless manner with the base station  102 . In turn, the base station  102  may be coupled to a core network  100 . As shown, the CN  100  may include a mobility management entity (MME)  322 , a home subscriber server (HSS)  324 , and a serving gateway (SGW)  326 . The CN  100  may also include various other devices known to those skilled in the art. 
     Operations described herein as being performed by the wireless network may be performed by one or more of the network devices shown in  FIG.  8   , such as one or more of the base station  102  or the CN  100 , and/or the MME  322 , HSS  324 , or SGW  326  in the CN  100 , among other possible devices. Operations described herein as being performed by the radio access network (RAN) may be performed, for example, by the base station  102 , or by other components of the RAN usable to connect the UE and the CN. 
       FIG.  9   —Example Cellular Environment 
       FIG.  9    illustrates an example cellular environment where multiple UEs are within the range of a macro cell or an LTE cell (e.g., which may be part of a master cell group (MCG)). Within the macro cell, multiple smaller cells (e.g., 5G or NR cells) may be available for providing connectivity to UE(s). The smaller cells may be secondary cells or part of a secondary cell group (SCG). 
     When a UE is configured with a SCG, the UE may maintain connectivity to both the MCG and the SCG. For example, for the MCG, the primary cell (PCell) may always be activated. In the SCG, the primary secondary cell (PSCell) may be activated or deactivated. In some aspects, the PSCell may always be activated (e.g., the SCG may always be in the activated state, and accordingly, the UE may always supports simultaneous reception and transmission in MCG and SCG. However, in other aspects, the PSCell&#39;s state may change, e.g., based on signaling between the network and the UE. 
       FIGS.  10 - 11 B —Example SCG Addition and Change Procedures 
       FIGS.  10 ,  11 A, and  11 B  illustrate example flow charts for SCG addition and change procedure(s) that may apply to “always activated” aspects, although they could also be used for aspects where the SCG and/or PSCell&#39;s state may change, e.g., between deactivated and activated or vice versa, as described in various aspects herein.  FIG.  10    may provide an exemplary secondary node addition procedure.  FIGS.  11 A and  11 B  may provide an exemplary SN Change (e.g., MN initiated) procedure. 
     Aspects of the method of  FIGS.  10 - 15    may be implemented by a wireless device, such as the UE(s)  106 , in communication with a network, e.g., via one or more base stations (e.g., BS  102 ) as illustrated in and described with respect to the Figures, or more generally in conjunction with any of the computer systems or devices shown in the Figures, among other circuitry, systems, devices, elements, or components shown in the Figures, among other devices, as desired. For example, one or more processors (or processing elements) of the UE (e.g., processor(s)  302 , baseband processor(s), processor(s) associated with communication circuitry, etc., among various possibilities) may cause the UE to perform some or all of the illustrated method elements. Similarly, one or more processors (or processing elements) of the BS (e.g., processor(s)  404 , baseband processor(s), processor(s) associated with communication circuitry, etc., among various possibilities) may cause the UE to perform some or all of the illustrated method elements. Note that while at least some elements of the method are described in a manner relating to the use of communication techniques and/or features associated with 3GPP specification documents, such description is not intended to be limiting to the disclosure, and aspects of the method may be used in any suitable wireless communication system, as desired. In various aspects, some of the elements of the methods shown may be performed concurrently, in a different order than shown, may be substituted for by other method elements, or may be omitted. Additional method elements may also be performed as desired. As shown, the method may operate as follows. 
     In  1012 , the master node (MN)  1004  may provide a SgNB (Secondary gNB) addition request to the secondary node (SN) for communication with the UE  1002 . In  1014 , the SN  1006  may provide a SgNB addition request acknowledge message to the MN  1004 . Accordingly, in  1016 , the MN  1004  may provide an RRCConnectionReconfiguration (e.g. using reconfigurationWithSync in secondaryCellGroup when RLC bearer is setup in SCG) to the UE  1002  indicating the addition of the SN  1006  to the SCG. In  1018 , the UE  1002  may transmit an RRCConnectionReconfigurationComplete to the MN  1004 , which in turn may provide a SgNB Reconfiguration Complete message in  1020  to the SN  1006 . 
     In one aspect, if communication between the UE and the network is configured with bearers requiring SCG radio resources (e.g., with the reconfigurationWithSync configuration), a random access channel (RACH) procedure may be used between the UE and the SN  1006 . Thus, in  1022 , the UE may trigger the RACH procedure for a newly configured secondary node (SN) PSCell. In the case of RACH failure (e.g., a timer failure associated with RACH, such as T304 failure), the UE may trigger a SCG failure procedure. 
     In some aspects, upon RACH completion, e.g., if reconfigurationWithSyuc was included in spCellConfig of an MCO or SCG and when MAC of an NR cell group successfully completes a RACH procedure triggered above, the UE may stop timer T304 for that cell group; stop timer T310 for source SPCell if running, apply the parts of the CSI reporting configuration, the scheduling request configuration and the sounding RS configuration that do not require the UE to know the SFN of the respective target SPCell, if any; and/or apply the parts of the measurement and the radio resource configuration that require the UE to know that the SFN of the respective target SPCell (e.g., measurement gaps, periodic CQI reporting, scheduling request configuration, sounding RS configuration), if any, upon acquiring the SFN of that target SPCell. 
     In some aspects, upon receiving the RRCReconfigurationComplete message for SCG addition/change and the UE successfully accessing SCG via RACH procedure, the network may assume the SCG addition/change procedure successfully completed and perform SN Status transfer and data forwarding in  1024  and  1026 . 
     In  1036 , a path update procedure may be performed, which may include ERAB Modification indication  1028  from the MN  1004  to the MME  1010 , a bearer modification  1030  between the SGW  1008  and MME  1010 , an end marker packet  1032  between the MN  1004 , SN  1006 , and SGW  1008 , and/or a ERAB modification confirm from the SGW  1008  to the MN  1004 . 
       FIGS.  11 A and  11 B  are similar to  FIG.  10   , but may correspond to a SN change procedure (e.g., MN initiated). As shown, in  1114 , the MN  1104  may transmit a SgNB addition request to the TSN (target SN)  1108 . In  1116 , the TSN  1108  may provide a SgNB addition request acknowledge to the MN  1104 . In  1118 , the MN  1104  may provide a release request to the SSN (source SN)  1106 , and in  1120 , the SSN  1106  may provide an acknowledge back to the MN  1104 . 
     In  1122 , the MN  1104  may provide an RRCConnectionReconfiguration (e.g., a “zoom out” reconfiguration) to the UE  1102 . The UE  1102  may provide a RRCConnectionReconfiguration response to the MN  1104  in  1124 , and the MN  1104  may provide a SgNB reconfiguration complete Message to the TSN  1108  in  1126 . 
     Accordingly, the UE  1102  may perform a RACH procedure with the TSN  1108  in  1128 . After, the SSN  1106  may provide an SN status transfer message to the MN  1104  in  1130 . Accordingly, the MN  1104  may provide an SN Status Transfer message to the TSN  1108  in  1132 . 
     In  1134 , data forwarding may be configured between the MN  1104 , SSN  1106 , TSN  1108 , and SGW  1110 . In  1136 , a secondary RAT data usage report message may be transmitted from the SSN  1106  to the MN  1104 . In  1138 , the MN  1104  may provide an ERAB modification indication to the MME  1112 . In  1140 , a bearer modification may occur between the SGW  1110  and the MME  1112 . In  1142 , an end marker packet  1142  may be exchanged between the MN  1104 , the SSN  1106 , and the TSN  11108 . In  1144 , a new path indication may be provided from the SGW  1110  and the TSN  1108 . The SGW  1110  may provide an ERAB modification confirm message to the UE  1102  in  1146 . Finally, in  1148 , the MN  1104  may provide a UE context release to the SSN  1106 . 
       FIGS.  12 - 16   —Example SCG Addition and Change Procedures 
       FIGS.  12 - 16    illustrate example flow charts for SCG addition and change procedure(s) that may apply to aspects where the SCG and/or PSCell&#39;s state may change, e.g., between deactivated and activated or vice versa, although they could also be applied to aspects where the SCG and/or PSCell&#39;s state is always active, as described in various aspects above. While these Figures are described separately, the various descriptions may apply to the different aspects herein. For example, the descriptions of  FIG.  12    may also apply to  FIGS.  13 - 16   , the descriptions of  FIG.  13    to  FIGS.  12 , and  14 - 16   , etc. Additionally, all of these descriptions may apply to other Figures or aspects associated therewith. 
     In some aspects, the cellular network (e.g., the MN) may configure a SCG state (e.g., an initial SCG state) as deactivated upon SCG (e.g., PSCell) addition/change, RRC resume, or handover for a UE. 
     However, UE operation when the SCG is configured in the deactivated state may not include PDCCH monitoring, UL/DL data transmission, SRS transmission, and/or SCG SCell activation, depending on the aspect or implementation. Accordingly, various aspects described herein may address how to configure changes in state of an SCG (PSCell) after being deactivated. These aspects may apply to situations for SCG/PSCell additions or changes, RRC resume, and/or handover, among other possibilities. Additionally, these aspects may be particularly applicable if the network configures reconfigurationWithSync in secondaryCellGroup at SCG/PSCell addition/change, RRC Resume and handover, etc. 
     While many aspects herein are described with regard to SCG addition/change (e.g., involving a MCG base station adding or configuring a SCG while maintaining its connection with the UE), they may also apply to other embodiments. For example, a source MN may provide the SCG addition/change as part of a handover process to a target MN. Accordingly, after handover, the UE may communicate with the new SCG and the target MN (rather than the source MN), which is part of the MCG. Thus, all aspects described herein (e.g., including  FIGS.  12 - 16   ) may apply to handovers as well as aspects where the MN remains the same. Additionally, these aspects may also apply in situations involving handover from a source SN to a target SN, e.g., described regarding  FIGS.  11 A and  11 B . These aspects may also apply to cases where there is handover from a source MN to a target MN as well as from a source SN to a target SN. 
       FIG.  12    illustrates an exemplary aspect where the SCG may be configured in the deactivated state upon the successful completion of RACH. For example, the network may set the initial SCG state as deactivated in an initial configuration message (e.g., RRC message) to the UE. Accordingly, the UE may perform a RACH procedure on the PSCell and set the SCG in deactivated state upon the RACH procedure&#39;s successful completion. 
     In more detail, in  1208 , the MN  1204  may provide signaling indicating addition of SN  1206  to the UE  1202 . For example, the MN  1204  may provide an RRC reconfiguration message to the UE  1202 . The RRC Reconfiguration message may indicate (e.g., explicitly): SCG addition, reconfigurationWithSync (RACH), and or an initial SCG deactivated state. Separately (and before, after, or concurrently with  1208 ), the MN  1204  and SN  1206  may perform an SCG addition procedure. 
     In  1212 , the UE  1202  may provide a response to the configuration of the SN  1206  to the MN  1204 , e.g., in an RRCReconfiguration Complete message. Accordingly, the MN  1204  may provide a confirmation of the SN addition in  1214 , e.g., via an SN Reconfiguration Complete message. 
     In  1216 , the UE  1202  may perform a RACH procedure with the SN  1206 . 
     During the first time period up to RACH procedure completion, the SCG and or PSCell may be configured in the activated state, regardless of the indication of SCG state from the MN (in this case, deactivated). In this first period of time, the UE may apply the SCC configuration, perform the RACH procedure, and/or deliver the SCG reconfiguration complete message via MCG RRC message. 
     During the second time period after the RACH procedure, the UE may apply the SCG configuration, set the SCG state to deactivated (based on the indication from the MN), and apply the deactivated state UE behavior including the timer. 
     The time when the RACH is successfully completed may be different for different types of procedures. For example, for CFRA (contention free random access), the time of successful RACH completion may be when the UE receives the Msg2 and/or RAR. As another example, for CBRA (contention based random access), the time of successful RACH completion may be when the UE received the PDCCH scrambled by the UE&#39;s C-RNTI in SCG. 
     Later, e.g., substantially after being in the deactivated state, the SN may be activated (e.g., UE initiated or network initiated) and the UE may be configured to communicate data with the MN and/or the SN (e.g., at the same time). For example, the UE may perform uplink data communication with the SN, the MN, and/or both the SN and the MN. 
       FIG.  13    illustrates an exemplary aspect where the network indicates the SCG is in the deactivated state during, the RACH procedure in SCG, but not in initial messaging (e.g., an RRC message) as in  FIG.  12   . For example, the UE may perform a RACH procedure in SCG in an activated state, and the network (e.g., the SN) may inform the UP to set SCG in deactivated state during the RACH procedure. 
     In more detail, in  1308 , the MN  1304  may provide signaling indicating addition of SN  1306  to the UE  1202 . For example, the MN  1304  may provide an RRC reconfiguration message to the UE  1302 . The RRC Reconfiguration message may indicate (e.g., explicitly): SCG addition and/or reconfigurationWithSync (RACH). The signaling may not indicate that the SCG is in the deactivated state. In some aspects the MN  1304  may also indicate an initial SCG activated state. Separately (and before, after, or concurrently with  1308 ), the MN  1304  and SN  1306  may perform an SCG addition procedure. 
     In  1312 , the UE  1302  may provide a response to the configuration of the SN  1306  to the MN  1304 , e.g., in an RRCReconfiguration Complete message. Accordingly, the MN  1304  may provide a confirmation of the SN addition in  1314 , e.g., via an SN Reconfiguration Complete message. 
     The UE  1302  may perform a RACH procedure with the SN  1306 , and the network (e.g., the SN  1306 ) may indicate a deactivated state during the RACH procedure. 
     For example, in a two step CBRA or CFRA RACH procedure, the UE  1302  may provide MsgA in  1316 , and the SN  1306  may respond with a deactivation in  1318  (e.g., within PDCCH scrambled with the C-RNTI of the UP  1302 , e.g., as part of MsgB). 
     As another example, in a four step CBRA RACH procedure, the UE  1302  may provide a CBRA preamble in  1320 , and the SN  1306  may respond with a Msg2 in  1322 . The UP  1302  may respond with a Msg3 (e.g., indicating SCG C-RNTI), and the SN  1306  may respond with an SCG deactivated state indication (e.g., within PDCCH scrambled by SCG C-RNTI) in  1326 , e.g., as part of Msg4. 
     As another example, in a four step CFRA, the UE  1302  may provide a preamble in  1328 , and the SN may respond with an SCG deactivated state indication in Msg2 in  1330 . The remaining two steps may then be performed to complete the RACH procedure. 
     Later, e.g., substantially after being in the deactivated state in  1330 , the SN may be activated (e.g., UE initiated or network initiated) and the UE may be configured to communicate data with the MN and/or the SN (e.g., at the same time). For example, the UE may perform uplink data communication with the SN, the MN, and/or both the SN and the MN. 
       FIG.  14    illustrates an exemplary aspect where the UE may skip an initial RACH procedure, but may perform a later RACH procedure according to the configured RACH configuration at the first activation (e.g., in RRC from the MN), which may be network initiated or UE initiated. For example, if the network sets the initial SCG state as deactivated in RRC message, the UE may not perform the RACH procedure on PSCell addition. Additionally, the UE may apply the SCG configuration immediately upon the UE acquiring the PSCell SFN, but may not start a timer for handover failure (e.g., the T304 timer). At the first activation (e.g., network initiated or UE initiated), the UE may trigger RACH PSCell to acquire the uplink sync in SCG according to the configured RACH configuration. 
     In more detail, in  1408 , the MN  1404  may provide signaling indicating addition of SN  1406  to the UE  1402 . For example, the MN  1404  may provide an RRC reconfiguration message to the UE  1402 . The RRC Reconfiguration message may indicate (e.g., explicitly): SCG addition, reconfigurationWithSync, RACH configuration, and/or an SCG deactivated state. Separately (and before, after, or concurrently with  1408 ), the MN  1404  and SN  1406  may perform an SCG addition procedure. 
     In  1412 , the UE  1402  may provide a response to the configuration of the SN  1406  to the MN  1404 , e.g., in an RRCReconfiguration Complete message. Accordingly, the MN  1404  may provide a confirmation of the SN addition in  1414 , e.g., via an SN Reconfiguration Complete message. 
     During this first period of time ( 1408 - 1414 ), the UE may apply the SCG configuration, deliver the SCG configuration (or reconfiguration) complete message, e.g., via MCG RRC message, and/or set the SCG in the deactivated state based on  1408 . 
     In a second period of time starting at  1416 , the UE  1402  may perform a RACH procedure, UE initiated SCG activation upon data arrival, using a RACH configuration provided by the network (e.g., provided in  1408 ). At this time, the UE may set the SCG in the activated state and trigger the RACH. 
     Alternatively, or additionally,  1418  and  1420  illustrate two different options for SCG activation indication, e.g., in a network initiated SCG activation. In  1418 , the SCG activation indication may be provided to the UE  1402  from the SN  1406 . In  1420 , the SCG activation indication may be provided to the UE  1402  from the MN  1404 . In both of these options, the activation indication may indicate a RACH resource for performing RACH. Accordingly, the UE may set the SCG in the activated state, trigger RACH according to the RACH configuration (e.g., indicated in  1408  and/or in  1418 / 1420 , as desired) in  1422 . Alternatively, if no dedicated-UE RACH is configured, the UE  1402  may perform CBRA RACE in  1422 . 
       FIG.  15    illustrates an exemplary aspect where the UE may skip the initial RACH procedure, and the network may not provide any RACH configuration at the SCG addition and/or change. For example, no RACH configuration may be provided in the SCG addition/change procedure, and the UE RRC procedure may be to apply all the SCG configuration immediately upon the UE acquiring the PSCell SFN. Accordingly, there may be no need to start a timer for handover failure (e.g., the T304 timer). 
     In more detail, in  1508 , the MN  1504  may provide signaling indicating addition of SN  1506  to the UE  1502 . For example, the MN  1504  may provide an RRC reconfiguration message to the UE  1502 . The RRC Reconfiguration message may indicate (e.g., explicitly): SCG addition, reconfigurationWithSync, and/or an SCG deactivated state. The signaling may not include a RACH configuration. Separately (and before, after, or concurrently with  1508 ), the MN  1504  and SN  1506  may perform an SCG addition procedure. 
     In  1512 , the UE  1502  may provide a response to the configuration of the SN  1506  to the MN  1504 , e.g., in an RRCReconfiguration Complete message. Accordingly, the MN  1504  may provide a confirmation of the SN addition in  1514 , e.g., via an SN Reconfiguration Complete message. 
     Activation of the SCG state may occur similarly to  FIG.  14   , except without using an initial RACH configuration. For example, the UE may perform RACH using generic (non-UE specific) resources for a UE-initiated procedure. Alternatively, or additionally, the steps of  1418  or  1420  and  1422  may be performed for network initiated RACH. 
       FIG.  16    illustrates an exemplary aspect where the network may enable a RACH-less mode for SCG activated state. For example, the network may configure the UE to skip the RACH in SCG. For timing advance (TA) Timer expiry and/or no valid TA, the UE may perform uplink transmission based on TA=0 or a fixed TA. Accordingly, the UE may not need to perform RACH procedure for transmissions with the SN. 
     In more detail, in  1608 , the MN  1604  may provide signaling indicating addition of SN  1606  to the UE  1602 . For example, the MN  1604  may provide an RRC reconfiguration message to the UE  1602 . The RRC Reconfiguration message may indicate (e.g., explicitly): SCG addition, reconfigurationWithSync and/or an SCG deactivated state. Separately (and before, after, or concurrently with  1608 ), the MN  1604  and SN  1606  may perform an SCG addition procedure. 
     In  1612 , the UE  1602  may provide a response to the configuration of the SN  1606  to the MN  1604 , e.g., in an RRCReconfiguration Complete message. Accordingly, the MN  1604  may provide a confirmation of the SN addition in  1614 , e.g., via an SN Reconfiguration Complete message. 
       1618  and  1620  indicate two options for SCG activation (e.g., at a later period of time, after remaining deactivated after  1614 ), which may be provided to the UE  1602  via the SN  1606  or the MN  1604  respectively. Accordingly, in  1622 , the UE may activate SCG and perform uplink transmission using TA=0 or some other fixed TA (e.g., previously indicated by the network, preconfigured by the UE, agreed upon by standards, etc.). 
     Exemplary Aspects 
     The following descriptions provide exemplary aspects corresponding to various aspects described herein, e.g., such as corresponding to the methods of  FIGS.  10 - 16   . 
     Example 1. A method of operating a wireless device, comprising: by the wireless device: establishing communication with a first base station, wherein the first base station is comprised in a master cell group (MCG); receiving signaling from the first base station configuring a second base station, wherein the second base station is comprised in a secondary cell group (SCG); establishing communication with the second base station based on the signaling received from the first base station at a first time, setting the second base station in a deactivated state, based on the signaling from the first base station configuring the second base station or establishing communication with the second base station; at a later time, setting the second base station in an activated state; and communicating with a base station in the MCG and the second base station in response to setting the second base station in the activated state. 
     Example 2. The method of Example 1, wherein the signaling from the first base station configuring the second configuration includes a random access channel (RACH) configuration, wherein said establishing communication with the second base station is performed using a RACH procedure using the RACH configuration. 
     Example 3. The method of any of the preceding Examples, wherein said establishing communication with the second base station is performed while the second base station is set to the activated state. 
     Example 4. The method of Example 3, wherein setting the second base station in the deactivated state is performed based on the signaling from the first base station indicating the deactivated state. 
     Example 5. The method of Example 3, wherein setting the second base station in the deactivated state is performed based on an indication of the deactivated state during a random access procedure. 
     Example 6. The method of Example 5, wherein setting the second base station in the deactivated stale is indicated in MsgB of a two step random access procedure. 
     Example 7. The method of Example 5, wherein setting the second base station in the deactivated state is indicated in Msg4 of a four step contention based random access procedure. 
     Example 8. The Example of claim  5 , wherein setting the second base station in the deactivated state is indicated in Msg2 of a four step contention free random access procedure. 
     Example 9. An apparatus comprising at least one processor configured to cause the wireless device to perform the method of any of Examples 1-8. 
     Example 10. The apparatus of Example 9, wherein the apparatus further includes wireless communication circuitry at least for communicating with the first base station and the second base station. 
     Example 11. A non-transitory computer readable memory medium storing program instructions executable by at least one processor to perform the method of any of Examples 1-8. 
     Example 12. A method of operating a wireless device, comprising: by the wireless device: establishing communication with a first base station, wherein the first base station is comprised in a master cell group (MCG); receiving signaling from the first base station configuring a second base station, wherein the second base station is comprised in a secondary cell group (SCG), and wherein the signaling from the first base station indicates a deactivated state for the second base station; at a first time, setting the second base station in the deactivated state based on the signaling from the first base station configuring the second base station; at a later time, setting the second base station in an activated state and establishing communication with the second base station based on the signaling received from the first base station; and communicating with a base station in the MCG and the second base station in response to setting the second base station in the activated state. 
     Example 13. The method of Example 12, wherein the signaling from the first base station configuring the second configuration includes a random access channel (RACH) configuration, wherein said establishing communication with the second base station is performed using a RACH procedure using the RACH configuration. 
     Example 14. The method of any of Examples 12-13, wherein said setting the second base station in the activated state and said communicating with the base station in the MCG and the second base station is performed in response to data for transmission by the wireless device, wherein said communicating with the base station in the MCG and the second base station includes transmitting the data. 
     Example 15. The method of any of Examples 12-13, wherein said setting the second base station in the activated state and said communicating with the base station in the MCG and the second base station is performed in response to receiving an activation message from the first base station or the second base station. 
     Example 16. The method of Example 15, wherein the activation message is received from the first base station, wherein the activation message indicates a resource for performing a random access channel (RACH) procedure, wherein said establishing communication with the second base station comprises performing the RACH procedure using the resource. 
     Example 17. The method of Example 15, wherein the activation message is received from the second base station, wherein the activation message indicates a resource for performing a random access channel (RACH) procedure, wherein said establishing communication with the second base station comprises performing the RACH procedure using the resource. 
     Example 18. The method of Example 12, wherein the signaling from the first base station configuring the second base station does not include a random access channel (RACH) configuration. 
     Example 19. The method of Example 18, wherein said establishing communication with the second base station and said communicating with the second base station does not include performing at RACH procedure. 
     Example 20. The method of Example 19, wherein said performing communication with the second base station includes using a predetermined timing advance value. 
     Example 21. An apparatus comprising at least one processor configured to cause the wireless device to perform the method of any of Examples 12-20. 
     Example 22. The apparatus of Example 21, wherein the apparatus further includes wireless communication circuitry at least for communicating with the first base station and the second base station. 
     Example 23. A non-transitory computer readable memory medium storing program instructions executable by at least one processor to perform the method of any of Examples 12-20. 
     Example 24. A method of operating a first base station, comprising: by the first base station; establishing communication with a wireless device, wherein the first base station is comprised in a master cell group (MCG) for the wireless device; performing a secondary cell group (SCG) addition procedure with a second base station; providing RRC signaling to the wireless device regarding the second base station; receiving a response from the wireless device in response to the RRC signaling, wherein the response indicates completion of the SCG addition; in response to receiving the response from the wireless device, providing a SCG addition or change completion indication to the second base station. 
     Example 25. The method of Example 24, wherein the RRC signaling indicates a deactivated state for the second base station. 
     Example 26. The method of Example 24, wherein the RRC signaling indicates a random access channel (RACH) configuration usable by the wireless device to perform a RACH procedure with the second base station. 
     Example 27. The method of Example 24, further comprising: alter providing the SCG addition completion indication to the second base station, providing an SCG activation message to the wireless device, wherein the SCG activation message indicates a random access channel (RACH) resource for performing a RACH procedure with the second base station. 
     Example 28. The method of Example 24, wherein the RRC signaling does not include a random access channel (RACH) configuration. 
     Example 29. An apparatus comprising at least one processor configured to cause the first base station device to perform the method of any of Examples 24-28. 
     Example 30. The apparatus of Example 29, wherein the apparatus further includes wireless communication circuitry at least for communicating with the wireless device and the second base station. 
     Example 31. A non-transitory computer readable memory medium storing program instructions executable by at least one processor to perform the method of any of Examples 24-28. 
     Example 32. A method of operating a base station, comprising: by the base station: performing a secondary cell group (SCG) addition procedure with a first base station, wherein the first base station is included in a master cell group (MCG) of a wireless device; receiving a SCG addition completion indication from the first base station, wherein the SCG addition completion indication is received in response to the first base station receiving a response of addition of the base station from the wireless device; establishing communication with the wireless device; and communicating with the wireless device in response to said establishing communication. 
     Example 33. The method of Example 32, wherein said establishing communication with the wireless device is performed using a random access channel (RACH) procedure, wherein the wireless device is in a SCG deactivated state upon completion of the RACH procedure, and wherein said communicating with the wireless device is performed after changing to an SCG activated state. 
     Example 34. The method of Example 32, wherein said establishing communication with the wireless device is performed using a random access channel (RACH) procedure, wherein the said establishing communication with the wireless device comprises indicating an SCG deactivated state in the RACH procedure, and wherein said communicating with the wireless device is performed after changing to an SCG activated state. 
     Example 35. The method of Example 32, wherein said establishing communication with the wireless device and said communicating with the wireless device is performed in response to a wireless device initiated random access channel (RACH) procedure, wherein the RACH procedure is performed using a RACH configuration provided by the first base station. 
     Example 36. The method of Example 32, wherein said establishing communication comprises: providing an SCG activation indication to the wireless device, wherein the SCG activation indication specifies a random access channel (RACH) resource for performing a RACH procedure; and performing the RACH procedure with the wireless device using the RACH resource. 
     Example 37. The method of Example 32, wherein said establishing communication and communicating with the wireless device is performed without performing a random access channel (RACH) procedure. 
     Example 38. The method of Example 34, wherein said communicating with the wireless device is performed using a predetermined timing advance value. 
     Example 39. An apparatus comprising at least one processor configured to cause the base station to perform the method of any of Examples 32-38. 
     Example 40. The apparatus of Example 39, wherein the apparatus further includes wireless communication circuitry at least for communicating with the wireless device and the first base station. 
     Example 41. A non-transitory computer readable memory medium storing program instructions executable by at least one processor to perform the method of any of Examples 32-38. 
     Aspects of the present disclosure may be realized in any of various forms. For example, some aspects may be realized as a computer-implemented method, a computer-readable memory medium, or a computer system. Other aspects may be realized using one or more custom-designed hardware devices such as ASICs. Still other aspects may be realized using one or more programmable hardware elements such as FPGAs. 
     In some aspects, a non transitory computer-readable memory medium may be configured so that it stores program instructions and/or data, where the program instructions, if executed by a computer system, cause the computer system to perform a method, any of a method aspects described herein, or, any combination of the method aspects described herein, or, any subset of any of the method aspects described herein, or, any combination of such subsets. 
     In some aspects, a device (e.g., UE) may be configured to include a processor (or a set of processors) and a memory medium, where the memory medium stores program instructions, where the processor is configured to read and execute the program instructions from the memory medium, where the program instructions are executable to implement any of the various method aspects described herein (or any combination of the method aspects described herein, or, any subset of any of the method aspects described herein, or, any combination of such subsets). The device may be realized in any of various forms. 
     In some aspects, a device includes: an antenna; a radio coupled to the antenna; and a processing element coupled to the radio. The device may be configured to implement any of the method aspects described above. 
     In some aspects, a memory medium may store program instructions that, when executed, cause a device to implement any of the method aspects described above. 
     In some aspects, an apparatus includes: at least one processor (e.g., in communication with a memory), that is configured to implement any of the method aspects described above. 
     In some aspects, a method includes any action or combination of actions as substantially described herein in the Detailed Description and claims. 
     In some aspects, a method is performed as substantially described herein with reference to each or any combination of the Figures contained herein, with reference to each or any combination of paragraphs in the Detailed Description, with reference to each or any combination of Figures and/or Detailed. Description, or with reference to each or any combination of the claims. 
     In some aspects, a wireless device is configured to perform any action or combination of actions as substantially described herein in the Detailed Description, Figures, and/or claims. 
     In some aspects, a wireless device includes any component or combination of components as described herein in the Detailed Description and/or Figures as included in a wireless device. 
     In some aspects, a non-volatile computer-readable medium may store instructions that, when executed, cause the performance of any action or combination of actions as substantially described herein in the Detailed Description and/or Figures. 
     In some aspects, an integrated circuit is configured to perform any action or combination of actions as substantially described herein in the Detailed Description and/or Figures. 
     In some aspects, a mobile station is configured to perform any action or combination of actions as substantially described herein in the Detailed Description and/or Figures. 
     In some aspects, a mobile station includes any component or combination of components as described herein m the Detailed Description and/or Figures as included in a mobile station. 
     In some aspects, a mobile device is configured to perform any action or combination of actions as substantially described herein in the Detailed Description and/or Figures. 
     In some aspects, a mobile device includes any component or combination of components as described herein in the Detailed Description and/or Figures as included in a mobile device. 
     In some aspects, a network node is configured to perform any action or combination of actions as substantially described herein in the Detailed Description and/or Figures. 
     In some aspects, a network node includes any component or combination of components as described herein in the Detailed Description and/or Figures as included in a mobile device. 
     In some aspects, a base station is configured to perform any action or combination of actions as substantially described herein in the Detailed Description and/or Figures. 
     In some aspects, a base station includes any component or combination of components as described herein in the Detailed Description and/or Figures as included in a mobile device. 
     In some aspects, a 5G NR network node or base station is configured to perform any action or combination of actions as substantially described, herein in the Detailed Description and/or Figures. 
     In some aspects, a 5G NR network node or base station includes any component or combination of components as described herein in the Detailed Description and/or Figures as included in a mobile device. 
     It is well understood that the use of personally identifiable information should follow privacy policies and practices that are generally recognized as meeting or exceeding industry or governmental requirements for maintaining the privacy of users. In particular, personally identifiable information data should be managed and handled so as to minimize risks of unintentional or unauthorized access or use, and the nature of authorized use should be clearly indicated to users. 
     Any of the methods described herein far operating a user equipment (UE) may be the basis of a corresponding method for operating a base station, by interpreting each message/signal X received by the UE in the downlink as message/signal X transmitted by the base station, and each message/signal transmitted in the uplink by the UE s a message/signal Y received by the base station 
     Although the aspects above have been described in considerable detail, numerous variations and modifications will become apparent to those skilled in the art once the above disclosure is fully appreciated, it is intended that the following claims be interpreted to embrace all such variations and modifications.

Metadata:
Filing Date: 20210112
Publication Date: 20240702
Grant Date: 20240702
Priority Date: 20210112
Inventors: XU, FANGLI
ZHANG, DAWEI
HU, HAIJING
PALLE VENKATA, Naveen Kumar R.
Gurumoorthy, Sethuraman
LOVLEKAR, SRIRANG A.
CHEN, YUQIN
WU, ZHIBIN
Assignee: APPLE INC
CPC Classifications: [{"code": "H04W74/0838", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04W74/0836", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04W74/0833", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04W36/08", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04W74/04", "inventive": true, "first": true, "tree": "[]"}, {"code": "H04W74/0833", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04W76/15", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04W74/0841", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04W36/08", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04W76/27", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04W76/15", "inventive": true, "first": true, "tree": "[]"}, {"code": "H04W76/15", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04W74/0841", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04W74/0833", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04W74/04", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04W36/08", "inventive": true, "first": true, "tree": "[]"}]
Family ID: 82446459