Efficient recovery with expected dead zone

Abstract

In one aspect, a method, performed by a user equipment (UE) in communication with a network, includes in response to determining that the UE is to enter a dead zone of the network, sending, to the network, an unavailability duration of time that is associated with the dead zone, and storing a context associated with the network. The method also includes restoring the communication to the network based on the stored context when the UE exits the dead zone of the network.

Description

EFFICIENT RECOVERY WITH EXPECTED DEAD ZONECROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims benefit and priority to U.S. Provisional Application No.63 / 583,210 filed September 15, 2023, entitled “Efficient Recovery With Expected Dead Zone”.The content of which is incorporated herein by reference in its entiretyTECHNICAL Field

[0002] This disclosure relates generally to wireless technology and more particularly to performing efficient recovery with expected dead zone by user equipment (UE) or by a network.BACKGROUND

[0003] Long-Term Evolution (LTE) is a standard for wireless communication and mobile broadband technology. It is the fourth generation (4G) of mobile network technology that succeeded the earlier 3G (Third Generation) networks. LTE improved upon data transfer rates, capacity, and overall performance compared to its predecessor technologies. It supported faster internet connections, lower latency, and improved spectral efficiency, making it more suitable for a variety of multimedia applications, video streaming, online gaming, and other data- intensive services.

[0004] New Radio (NR) is the fifth generation mobile network (5G). NR a wireless standard that aims to improve upon data transmission speed, reliability, availability, and more, using Massive MIMO, beamforming, a flexible spectrum, and other innovations. The wireless standard includes procedures that may be implemented by a transmitting device or a receiving device that improves the latency, the speed, and the reliability of uplink and downlink transmissions compared to its predecessors.

[0005] Wireless networks may rely on transmission of electromagnetic signals through air, water, walls, etc. Structures may inhibit or block this transmission, resulting in one or more network dead zones where communication is reduced.SUMMARY

[0006] Aspects of the present disclosure relate to 4G LTE or 5G new radio (NR) operating in the licensed spectrum or in the shared and unlicensed spectrum (NR-U).

[0007] In an aspect, a method, performed by a user equipment (UE) in communication with a network, comprises determining whether a UE is to enter a dead zone of the network. In response to determining that the UE is to enter a dead zone of the network, the method includes sending an unavailability duration of time that is associated with the dead zone, and storing a context associated with the network. The method includes restoring the communication to the network with the stored context when the UE exits the dead zone of the network. Storing the context may include storing a 5G mobility management (5GMM) context and a 5G session management (5GSM) context in non-volatile memory. Sending the unavailability duration of time may include sending a request for extension of a real time protocol (RTP) timer for the unavailability duration of time, and storing the context includes saving a last RTP serial number in a RTP buffer of the UE. Restoring the communication to the network with the stored context may resume or continue a call or data session of the UE that was interrupted by the dead zone.

[0008] In an example, in response to the UE exiting the dead zone prior before the unavailability duration of time is complete, the method may restore the communication to the network with the stored context.

[0009] The method may further include de-registering from the network in response to determining that the unavailability duration of time associated with the dead zone is greater than a threshold. De-registering from the network may include sending a de-regi strati on request that includes an indication of the unavailability duration of time, to the network.

[0010] In an example, determining that the UE is to enter the dead zone may be performed based on one or more conditions including at least one of: a location of the UE, a time of day, a day of week, a baseband pattern, or a sensor measurement such as from an accelerometer, a gyroscope, a pedometer, a magnetometer, or a barometer. In an example, determining that the UE is to enter the dead zone includes applying a machine learning model to the one or more conditions to infer that the UE is to enter the dead zone.

[0011] While the UE is in the dead zone, in response to the UE being gripped, the method may include using upper hemisphere antennas of the UE for uplink transmission. Additionally, or alternatively, in response to the UE being ungripped, the method may perform an automatic transmit diversity (ATD) for a plurality of antennas of the UE.

[0012] In response to the dead zone interrupting a call, the UE may store packet data units (PDUs) and a radio resource control (RRC) state of the UE as the context.

[0013] In an aspect, a method performed by network in communication with a user equipment (UE) includes receiving a registration request from the UE, the registration request including anunavailability duration of time associated with a dead zone of the network; sending, to the UE, a registration accept message; storing a context associated with the UE; and restoring the communication to with UE based on the context when the UE exits the dead zone of the network. In response to receiving the registration request from the UE, the method may include extending a time out associated with an active session of the UE for at least the unavailability duration of time.

[0014] The method may include, sending, by the network, the unavailability duration of time to a second UE, in response to the UE being in a call with the second UE over the network when the registration request is received from the UE. Sending the unavailability duration of time to the second UE may cause the second UE to present a notification associated with the UE being unavailable to a display.

[0015] The method may further comprise receiving a de-regi strati on request from the UE, the de-regi strati on request including the unavailability duration of time; and sending a deregistration accept to the UE. In response to receiving the de-registration request from the UE, the network may refrain from storing the context associated with the UE.

[0016] Receiving the registration request from the UE may include receiving a request for extension of a real time protocol (RTP) timer for the unavailability duration of time. Sending the registration accept message may include sending an acceptance that the RTP timer is extended for the unavailability duration of time.

[0017] In an aspect, an apparatus may comprise a processor coupled to non-transitory computer memory storing instructions that, when executed by the processor, cause the processor to perform the above operations performed by a UE or by a network (e.g., base station).

[0018] In an aspect, a non-transitory computer readable memory stores instructions that, when executed by a processor, causes performance of the above operations performed by the UE or by the network. Other technical features may be readily apparent to one skilled in the art from the following figures, descriptions, and claims.BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In the figures of the accompanying drawings, aspects described are illustrated by way of example and not by limitation.

[0020] FIG. 1 illustrates an example wireless communication system, according to an aspect.

[0021] FIG. 2 illustrates uplink and downlink communications, according to an aspect.

[0022] FIG. 3 illustrates an example block diagram of a user equipment (UE), according to an aspect.

[0023] FIG. 4 illustrates an example block diagram of a base station (BS), according to an aspect.

[0024] FIG. 5 illustrates an example block diagram of cellular communication circuitry, according to an aspect.

[0025] FIG. 6 shows an example diagram of a UE that is in communication with a network to perform efficient recovery with respect to an expected dead zone, according to an aspect.

[0026] FIG. 7 illustrates an example of operations performed by a UE for efficient recovery in expected dead zones, according to an aspect.

[0027] FIG. 8 illustrates an example of operations performed by a network for efficient recovery in expected dead zones, according to an aspect.

[0028] FIG. 9 illustrates an example of flow diagram for efficient recovery in expected dead zones, according to an aspect.

[0029] FIG. 10 illustrates examples for inferring a dead zone based on one or more conditions, according to an aspect.

[0030] FIG. 11 illustrates examples for managing call and data based on inferring a dead zone, according to an aspect.

[0031] FIG. 12 illustrates an example sequence diagram table for performing an efficient recovery based on an expected unavailability period, according to an aspect.

[0032] FIG. 13 illustrates an example sequence diagram for de-registering from the network in response to determining an expected unavailability period, according to an aspect.

[0033] FIG. 14 illustrates an example user equipment with multiple antennae operation during a network unavailability period, according to an aspect.DETAILED DESCRIPTION

[0034] Aspects described relate to enhancement of UE and network behavior with respect to a network dead zone. It will be apparent, however, to one skilled in the art, that aspects of the present disclosure may be practiced variations of the specific details described. In other instances, well-known components, structures, and techniques have not been shown in detail in order not to obscure the understanding of this description.

[0035] Reference in the specification to “some aspects” or “an aspect” means that a particular feature, structure, or characteristic described in connection with the aspect can be included in at least one aspect of the disclosure. The appearances of the phrase “in some aspects” in various places in the specification do not necessarily all refer to the same aspect.

[0036] In the following description and claims, the terms “coupled” and “connected,” along with their derivatives, may be used. “Coupled” is used to indicate that two or more elements, which may or may not be in direct physical or electrical contact with each other, co-operate or interact with each other. “Connected” is used to indicate the establishment of communication between two or more elements that are coupled with each other.

[0037] The processes depicted in the figures that follow, are performed by processing logic that comprises hardware (e.g., circuitry, dedicated logic, etc.), software (such as is run on a general- purpose computer system or a dedicated machine), or a combination of both. Although the processes are described below in terms of some sequential operations, it should be appreciated that some of the operations described may be performed in different order. Moreover, some operations may be performed in parallel rather than sequentially.

[0038] The terms “server,” “client,” and “device” are intended to refer generally to data processing systems rather than specifically to a particular form factor for the server, client, and / or device.

[0039] FIG. 1 illustrates a simplified example of a 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.

[0040] As shown, the example wireless communication system includes a base station 102 A which communicates over a transmission medium with one or more user devices 106A, 106B, etc., through 106N. Each of the user devices may be referred to as a “user equipment” (UE).

[0041] The base station (BS) 102A 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 106N.

[0042] The communication area (or coverage area) of the base station may be referred to as a “cell.” The base station 102A 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, Universal Mobile Telecommunications Service (UMTS) (associated with, for example, WCDMA or TD- SCDMA air interfaces), LTE, LTE-Advanced (LTE-A), 5G new radio (5G NR), HSPA, 3GPP2CDMA2000 (e.g., IxRTT, IxEV-DO, HRPD, eHRPD), etc. Note that if the base station 102A is implemented in the context of LTE, it may alternately be referred to as an ‘eNodeB’ or ‘eNB’. Note that if the base station 102A is implemented in the context of 5G NR, it may alternately be referred to as ‘gNodeB’ or ‘gNB’.

[0043] As shown, the base station 102A 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 102A may facilitate communication between the user devices and / or between the user devices and the network 100. In particular, the cellular base station 102 A may provide UEs 106 with various telecommunication capabilities, such as voice, SMS and / or data services.

[0044] Base station 102A and other similar base stations (such as base stations 102B . . . 102N) 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 106A-N and similar devices over a geographic area via one or more cellular communication standards.

[0045] Thus, while base station 102A may act as a “serving cell” for UEs 106A-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 base stations 102B-N and / or any other base stations), 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. For example, base stations 102A-B illustrated in FIG. 1 might be macro cells, while base station 102N might be a micro cell. Other configurations are also possible.

[0046] In some aspects, base station 102A 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.

[0047] 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 awireless 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, IxRTT, IxEV-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 or DVB-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.

[0048] FIG. 2 illustrates UE 106A that can be in communication with a base station 102 through uplink and downlink communications, according to some aspects. The UEs may each 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.

[0049] The UE may include a processor that is configured to execute program instructions stored in memory. The UE may perform any of the method aspects described herein by executing such stored instructions. Alternatively, or in addition, the UE 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.

[0050] The UE may include one or more antennas for communicating using one or more wireless communication protocols or technologies. In some aspects, the UE may be configured to communicate using, for example, CDMA2000 (IxRTT / lxEV-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 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.

[0051] In some aspects, the UE may include separate transmit and / or receive chains (e.g., including separate antennas and other radio components) for each wireless communicationprotocol with which it is configured to communicate. As a further possibility, the UE 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 might include a shared radio for communicating using either of LTE or 5G NR (or LTE or IxRTTor LTE or GSM), and separate radios for communicating using each of Wi-Fi and Bluetooth. Other configurations are also possible.

[0052] 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 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.

[0053] 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.

[0054] 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.

[0055] 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 radio access technologies (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.

[0056] 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.

[0057] 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.

[0058] 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.

[0059] As noted above, the communication device 106 may be configured to communicate using wireless and / or wired communication circuitry. The communication device 106 may also be configured to determine a physical downlink shared channel scheduling resource for a user equipment device and a base station. Further, the communication device 106 may be configured to group and select CCs from the wireless link and determine a virtual CC from the group of selected CCs. The wireless device may also be configured to perform a physical downlink resource mapping based on an aggregate resource matching patterns of groups of CCs.

[0060] As described herein, the communication device 106 may include hardware and software components for implementing the above features for determining a physical downlink shared channel scheduling resource for a communications device 106 and a base station. 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.

[0061] 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.

[0062] Further, as described herein, cellular communication circuitry 330 and short-range wireless communication circuitry 329 may each include one or more processing elements. In other words, one or more processing elements may be included in cellular communication circuitry 330 and, similarly, one or more processing elements 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 230. 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 32. 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.

[0063] 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 (ROM) 450) or to other circuits or devices.

[0064] 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.

[0065] 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).

[0066] 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 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 5GNR 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. In some aspects, the base station can operate in 5G NR-U mode.

[0067] The base station 102 may include at least one antenna 434, and possibly multiple antennas. The 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 via radio 430. The antenna 434 communicates with the radio 430 via communication chain 432. Communication chain 432may 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, 5G NR-U, LTE, LTE-A, GSM, UMTS, CDMA2000, Wi-Fi, etc.

[0068] 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 and 5G NR-U. 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 ).

[0069] 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.

[0070] In addition, as described herein, processor(s) 404 may be comprised of one or more processing elements. In other words, one or more processing elements may be included in processor(s) 404. 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.

[0071] Further, as described herein, radio 430 may be comprised of one or more processing elements. In other words, one or more processing elements may be included in radio 430. 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.

[0072] 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. 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.

[0073] 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 5GNR). 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.

[0074] 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 335a.

[0075] 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. Insome aspects, receive circuitry 542 may be in communication with DL front end 560, which may include circuitry for receiving radio signals via antenna 335b.

[0076] 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 front end 572).

[0077] As described herein, the modem 510 may include hardware and software components for implementing the above features or for determining a physical downlink shared channel scheduling resource for a user equipment device and a base station, 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.

[0078] In addition, as described herein, processors 512 may include one or more processing elements. Thus, processors 512 may include one or more integrated circuits (ICs) that are configured to perform the functions of processors 512. In addition, each integrated circuit may include circuitry (e.g., first circuitry, second circuitry, etc.) configured to perform the functions of processors 512.

[0079] As described herein, the modem 520 may include hardware and software components for implementing the above features for determining a physical downlink shared channel scheduling resource for a user equipment device and a base station, as well as the various other techniques described herein. The processors 522 may be configured to implement part or all ofthe 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.

[0080] In addition, as described herein, processors 522 may include one or more processing elements. Thus, processors 522 may include one or more integrated circuits (ICs) that are configured to perform the functions of processors 522. In addition, each integrated circuit may include circuitry (e.g., first circuitry, second circuitry, etc.) configured to perform the functions of processors 522.

[0081] 5G (also referred to as new radio) supports multi-antenna transmission, beam-forming, and simultaneous transmission from multiple geographically separates sites. 5G physical channels provide flexible communication between the 5G base stations and the UEs. 5G NR has specified the physical channels for 5G networks that can be used either for Downlink or Uplink communication. 5G NR physical channels used for uplink communication includes the physical uplink shared channel (PUSCH), the physical uplink control channel (PUCCH), and the physical random-access channel (PRACH). Reference signals such as demodulation reference signal DM- RS, phase tracking reference signal (PT-RS), and sounding reference signal (SRS) may be transmitted by the network or UE so that the receiving party may measure various qualities relating to the transmitter and adjust a network functionality accordingly. 5G NR supports the simultaneous transmission on PUSCH and PUCCH. PUSCH is typically used to carry the user data and optionally, can carry uplink control information (UCI).

[0082] PDSCH stands for Physical Downlink Shared Channel and is a channel used to deliver data from the base station (e.g., gNb) to the user equipment (UE) in the downlink direction. PDSCH supports high data rates and low latency for a wide range of applications and services. It uses advanced modulation and coding schemes, as well as multiple antenna techniques such as MIMO (Multiple Input Multiple Output), to maximize spectral efficiency and improve the overall performance of the network. PDSCH is also used in conjunction with other channels, such as the Physical Downlink Control Channel (PDCCH) and Physical Hybrid ARQ Indicator Channel (PHICH), to support features such as channel state information reporting, scheduling and retransmission of data packets, and HARQ (Hybrid Automatic Repeat Request) feedback.PDSCH enables the delivery of high-speed data and low-latency services to users in the downlink direction, and supports a range of advanced features and capabilities that promote efficient and reliable operation of the network.

[0083] Radio Resource Control (RRC) is a protocol layer that exists between the radio access network (RAN) and the core network in 5G. RRC is used to manage radio resources, including the establishment, maintenance, and release of radio connections between the user equipment (UE) and the base station. The RRC protocol performs several essential functions including connection establishment, connection maintenance, and connection release. RRC handles the procedures for establishing a connection between the UE and the base station. This includes procedures such as random access, initial cell search, and authentication. Once a connection is established, RRC is responsible for maintaining the connection and managing the radio resources efficiently. It ensures the appropriate quality of service (QoS) for the UE and handles mobility- related events, such as handovers between cells or handovers between different types of 5G networks (e.g., from 5G New Radio to 5G Core). When the UE no longer needs the connection or if there are other reasons for releasing it, RRC handles the procedures for releasing the connection and freeing up the associated radio resources. The RRC protocol operates on top of the physical layer and the medium access control (MAC) layer in the protocol stack. It communicates with other layers in the 5G system, such as the packet data convergence protocol (PDCP), radio link control (RLC), and the user plane, to support efficient and reliable communication between the UE and the network.

[0084] RRC protocol defines several states that a UE can be in. These states determine the level of connectivity and resource allocation between the UE and the network. The RRC states in 5G are RRC IDLE, RRC INACTIVE, and RRC CONNECTED.

[0085] In RRC Idle (RRC IDLE) state, the UE is not actively connected to the network. It is not assigned any dedicated resources, and its radio interface is deactivated. The UE periodically monitors system information broadcasts from the network to stay informed about available cells and other relevant network parameters. When the UE needs to establish a connection or perform a service request, it transitions to a RRC connected state.

[0086] When the UE is in RRC inactive (RRC IN ACTIVE) state, it has limited 5G resources allocated and uses primarily the LTE network for connectivity. In this state, the UE can quickly transition to the RRC CONNECTED state when one or more triggering events occur, as defined by one or more standards.

[0087] RRC Connected (RRC CONNECTED) state represents an active connection between the UE and the network. It can be further divided into sub-states: a. RRC Connected lnit: The initial sub-state where the UE has just established an RRC connection with the network. b. RRC Connected: The UE is in a stable connected state, and it can exchange data and signaling with the network (e.g., over physical uplink and physical downlink channels). It can receive and transmit data, perform handovers, and execute various procedures. c. RRC Connected Reconfiguring: The UE is undergoing a reconfiguration of its RRC connection parameters, such as changing the radio bearer configuration or updating network configuration information. d. RRC Connected Suspend: The UE temporarily suspends its RRC connection while maintaining radio resources for a specified period. It is typically used in power-saving scenarios to conserve energy. e. RRC Connected Release: The UE is releasing its RRC connection, terminating the active connection with the network.

[0088] Each RRC state has its own specific behaviors performed by the UE and network which results in specific power consumption characteristics and signaling procedures for the state (or sub-state). The network and the UE manage RRC state transitions based on numerous factors such as network conditions, service requirements, mobility, and power optimization.

[0089] A radio access technology (RAT) is the underlying physical connection method for a radio communication network. A UE may support several RATs in one device such as Bluetooth, Wi-Fi, and GSM, UMTS, LTE or 5G NR. Similarly, a network as described in the various examples, may be a non-homogenous network (e.g., comprising different RATs that a UE may switch between). A UE may select between the type of RAT being used to connect to the Internet. A UE, while connected using a RAT, may perform neighbor cell measurements and sends measurement report to the network. Based on this measurement report provided by the UE, the network may initiate handover from the UE's current RAT to another RAT, e.g. from NR to LTE, from LTE to NR, etc. Once the handover with the new RAT is completed, the channels used by the previous RAT may be released by the UE (e.g., a local release).

[0090] FIG. 6 shows an example diagram of a UE that is in communication with a network to perform efficient recovery with respect to an expected dead zone, according to an aspect.

[0091] UE 602 may correspond to a UE as described in other sections (e.g., UE 106). Network 604 may correspond to a long term evolution (LTE) network or an NR network, or a non-homogenous network. The UE 602 may be in communication with network 604, for example, through uplink and downlink communications between the UE 602 and a serving cell of network 604.

[0092] Generally, UE 602 may perform various network measurements (e.g., signal strength measurements) of the serving cell and of each of the neighboring cells. The UE may perform one or more comparisons between the signal measurements to determine whether to stay on the current serving cell switch to one of the neighbor cells. For example, a UE may measure a reference signal received power (RSRP), a received signal strength indicator (RS SI), a reference signal received quality (RSRQ), or other measurement associated with the measured energy of a reference signal transmitted by a cell. Depending on the value of each of the measurements, the UE and network 604 may work together to perform a handover of the UE to one of the neighboring cells or in some case, to a different radio access technology (RAT).

[0093] There are some condition or conditions that may cause a network dead zone 610, such as an enclosed space (e.g., an elevator, a tunnel, an underground location, signal interference, etc.) where communication with the network becomes so degraded or non-existent that the network 604 becomes unavailable to the UE 602. A dead zone 610 may be referred to as a physical region and / or time duration in which the user equipment has a reduced or complete loss of communication with the network. The UE becomes out of service (OOS) while in the network dead zone 610.

[0094] On each occasion when a user enters network dead zone 610, a UE 602 may experience a call drop, data stalls issues, loss of audio, or other issues. This effect may be especially felt in live communication applications such as a voice or video call. For example, user 608 may be on an active audio / video call such as voice over LTE (VoLTE), FToC, etc.) with another party 612 over network 604. When user 608 enters network dead zone 610, communication between UE 602 and UE 614 may become strained or drop off. Party 612 at the other end of the call may not know the reason for this loss of audio. The party 612 may keep talking without knowledge that the communication to user 608 is interrupted. Sometimes the other party 612 may end a call prematurely or repeatedly try to contact user 608 while the user 608 is still in the network dead zone 610, which may lead to a poor user experience for the other party 612 and user 608.

[0095] A network dead zone 610 may be detectable or anticipated ahead of time by a UE 602. For example, a UE may learn to predict when it will network dead zones that UEs experience repeatedly (e.g., daily), such as elevators, subways, garages, etc. In such scenarios where the UEanticipates a network dead zone 610, the UE may deduce the unavailability duration of the UE which may be referred to as how long the UE will be in the network dead zone 610.

[0096] For example, the UE may determine a network unavailability duration for ‘X’ seconds at approximately 9: 15am every morning due to a user consistently entering the same elevator at that time on weekdays for ‘X’ seconds. Upon determining the expected unavailability duration, the UE 602 may notify the other party 612 and hold all the associated timers to retain the active voice call with party 612, to prevent unwanted ‘Out of Service’, ‘Call Failure’, ‘Redundant Scanning’ and ‘Retries’. The UE may hold its current state for the unavailability duration of time and resume network operations (e.g., a call with party 612) gracefully upon recovery of the network communication, such as when it leaves network dead zone 610. The unavailability may be determined based on an average, a best fit, etc., using historical data of the one or more conditions of the UE.

[0097] UE 602 may determine that it is to enter network dead zone 610 of network 604. UE 602 may send, to network 604, an unavailability duration of time that is associated with the dead zone. For example, if the UE determines that it will be in network dead zone 610 for ‘X’ seconds, the UE may send the unavailability duration of time as ‘X’ seconds to the network, or an amount of time based on ‘X’ seconds (e.g., a range). UE 602 may store a context associated with the network 604 and restore the communication to the network 604 with the stored context, when the UE 602 exits the network dead zone 610.

[0098] UE 602 may include sensors 606 it may use sense various conditions of UE 602 which it may use to help determine when in the near future it will enter network dead zone 610, and how for how long (e.g., the unavailability duration of time). For example, sensors 606 may include a receiver that UE 602 may use to as a global positioning system (GPS) antenna to determine a location of the UE 602. Sensors 606 may further include one or more of: an accelerometer, a gyroscope, a pedometer, a magnetometer, or a barometer. The UE may determine that the UE is to enter the network dead zone 610, and for how long the UE 602 may be in that network dead zone 610, based on one or more conditions including at least one of: the location of the UE, a time of day, a day of the week, a baseband pattern, or sensor data from an accelerometer, a gyroscope, a pedometer, a magnetometer, or a barometer. The one or more conditions may be evaluated over time to determine a dependable pattern of the conditions which may strongly correlate to the UE losing communication with the network for the unavailability duration. In an example, determining that the UE is to enter the dead zone includes applying, by UE 602, a machine learning (ML) model to the one or more conditions to infer that the UE is toenter the dead zone at time ‘X’ for duration ‘Y’. The ML may be trained to correlate the inputs (the one or more conditions) to an output (e.g., a type of dead zone such as ‘elevator’, ‘tunnel’, etc., an unavailability duration of time, or both). The ML model may include an artificial neural network, a linear regression model, a k-nearest neighbors algorithm, clustering, or other ML model. The ML model may be trained through supervised or unsupervised training, using the one or more sensed conditions of the UE 602 over time, or off-line (e.g., remotely), or a combination thereof.

[0099] Aspects described here with respect to FIG. 6 are not exhaustive. Additional details of operations that are described in other sections, such as with respect to FIG. 7 - FIG. 14 may correspond to the operations described with respect to FIG. 6.

[0100] FIG. 7 illustrates an example method performed by a UE for efficient recovery in expected dead zones, according to an aspect. The method 700 may be performed by processing logic of a UE, which may be coupled to a transceiver, where the processor may execute instructions stored on computer-readable memory to perform the method described. The method may be performed by user equipment (UE) in communication with a network. The method may be performed by processing logic that may comprise hardware (e.g., circuitry, dedicated logic, programmable logic, a processor, a processing device, a central processing unit (CPU), a system- on-chip (SoC), a transmitter, a receiver, etc.), software (e.g., instructions running / executing on a processing device), firmware (e.g., microcode), or a combination thereof.

[0101] Some of the operations described with respect to method 700 may correspond to aspects described in other sections. The method illustrates example functions used by various embodiments. Although specific function blocks ("blocks") are disclosed in the method, such blocks are examples. That is, embodiments are well suited to performing various other blocks or variations of the blocks recited in the method. It is appreciated that the blocks in the method may be performed in an order different than presented.

[0102] At decision block 702, in response to determining that the UE is to enter a dead zone of the network, the method proceeds to block 704. If not, the method may be done. Determining that the UE is to enter the dead zone may be performed based on one or more conditions including at least one of: a location of the UE, a time of day, a day of week, a baseband pattern, or sensor data from an accelerometer, a gyroscope, a pedometer, a magnetometer, and / or a barometer. Additionally, or alternatively, determining that the UE is to enter the dead zone includes applying a machine learning model to the one or more conditions to infer that the UE is to enter the dead zone. Additional details regarding how to predict that the UE is to enter thedead zone and how long the unavailability will be are described with respect to FIG. 10 and FIG. 11. In an example, the determination that the UE is to enter the dead zone may be imminent (e.g., within the next 5 seconds) or as early as possible to predict that the UE is to enter the dead zone given the current conditions of the UE.

[0103] At block 704, method 700 sends an unavailability duration of time that is associated with the dead zone. In an example, sending the unavailability duration of time may include sending a request for extension of a real time protocol (RTP) timer for the unavailability duration of time.

[0104] At block 706, method 700 stores a context associated with the network. Storing the context may include storing a 5G mobility management (5GMM) context, a 5G session management (5GSM) context, or both, in memory (e.g., non-volatile memory) of the UE. In an example, in response to the dead zone interrupting a call, the UE stores packet data units (PDUs) and a radio resource control (RRC) state of the UE as the context. In an example, the context may include storing a serial number of the last real time protocol (RTP) packet in the RTP buffer of the UE and / or the last active RAT.

[0105] At block 708, method 700 restores the communication to the network with the stored context when the UE exits the dead zone of the network. In an example, in response to the UE exiting the dead zone (e.g., before the unavailability duration of time is complete), the UE may restore the communication to the network with the stored context. The UE may restore the communication to the network with the stored context which may resume a call or data session of the UE that was interrupted by the dead zone. For example, UE 602 may resume a call or data session with a second UE 614 after UE exits network dead zone 610, to resume the call with UE 614 which was interrupted by entering the dead zone.

[0106] In an example, in response to determining that unavailability duration of time associated with the dead zone is greater than a threshold, the method may include de-registering from the network. De-registering from the network may include sending, to the network, a de-registration request that includes an indication of the unavailability duration of time.

[0107] In an example, while the UE is in the dead zone, the method may adjust antennae operation based on grip state. For example the method may include detecting a grip state of the UE. In response to the UE being gripped, the method may include using upper hemisphere antennas for uplink transmission, and in response to the UE being ungripped, the method may include performing an automatic transmit diversity (ATD) for a plurality of antennas of the UE.

[0108] FIG. 8 shows an example method performed by a network for efficient recovery in expected dead zones, according to an aspect. The method 800 may be performed by processing device of a network (e.g., a base station) where the processing device may execute instructions stored on computer-readable memory to perform the method described. The method may be performed by processing logic that may comprise hardware (e.g., circuitry, dedicated logic, programmable logic, a processor, a processing device, a central processing unit (CPU), a system- on-chip (SoC), a transmitter, a receiver, etc.), software (e.g., instructions running / executing on a processing device), firmware (e.g., microcode), or a combination thereof.

[0109] Some of the operations described with respect to method 800 may correspond to aspects described in other sections. The method illustrates example functions used by various embodiments. Although specific function blocks ("blocks") are disclosed in the method, such blocks are examples. That is, embodiments are well suited to performing various other blocks or variations of the blocks recited in the method. It is appreciated that the blocks in the method may be performed in an order different than presented.

[0110] At block 802, method 800 receives a registration request from the UE, the registration request including an unavailability duration of time associated with a dead zone of the network. This may be a request from the UE to extend a time out associated with an active session of the UE.[OHl] At block 804, method 800 sends, to the UE, a registration accept message. The network may extend the time out associated with the active session of the UE (e.g., for at least the unavailability duration of time), and send the registration accept message to the UE to indicate to the UE that the time out for the active session has been extended.

[0112] At block 806, method 800 stores a context associated with the UE. The context may include information related to an active session of the UE at the time of the interruption.

[0113] At block 808, method 800 restores the communication to with UE based on the context when the UE exits the dead zone of the network. This may include restoring the active session of the UE that was interrupted by the dead zone of the network, using the context (e.g., UE state, last sent packet associated with the session, last received packet associated with the session, etc.).

[0114] In an example, in response to the UE being in a call with a second UE over the network when the registration request is received from the UE, the network sends the unavailability duration of time to the second UE. This may cause the second UE to present a notificationassociated with the UE being unavailable (e.g., “the UE you are on a call with is temporarily unavailable but may return in ‘X’ seconds").

[0115] In an example, the method further includes receiving a de-regi strati on request from the UE, the de-registration request including the unavailability duration of time, and sending a deregistration accept to the UE. This may be received from the UE when the unavailability duration is above a threshold amount of time in which it would be undesirable to pause and resume a call. In an example, in response to receiving the de-registration request from the UE, the network refrains from storing the context associated with the UE.

[0116] In an example, receiving the registration request from the UE includes receiving a request for extension of a real time protocol (RTP) timer for the unavailability duration of time. In response, the network may reset or adjust the RTP timer for the active session of the UE by adding the unavailability duration of time to the RTP timer so that the RTP timer does not time out. The network may send the registration accept message to the UE, including sending an acceptance that the RTP timer is extended for the unavailability duration of time.

[0117] FIG. 9 illustrates an example of flow diagram for efficient recovery in expected dead zones, according to an aspect. The diagram illustrates operations performed from a UE perspective. Some of the operations described in FIG. 9 may correspond to those of FIG. 7.

[0118] At block 902, the device (e.g., UE) enters or is on an active call (e.g., a VoIP) call or video call, with another device. An active call can be described as a real-time call in which communications (voice or video signals) are sent back and forth as they are generated between devices, with minimal delay that may result from processing and transmission of such signals.

[0119] At block 904, the device detects a potential upcoming dead zone. In response to detecting a potential upcoming dead zone, at block 906, the device evaluates whether the unavailability duration (shown as ‘t impact’) is less than a threshold. If the duration is less than the threshold, this may indicate that it is desirable to pause the active call with the other device. If the unavailability duration is not less than the threshold, this may indicate that the device will be in the dead zone for an extended period of time, in which case it may not be desirable to hold resources for pausing and resuming the call.

[0120] In response to the unavailability duration not being less than the threshold, the UE may proceed to block 908 and enter a “Call dead” mode. At block 910, the UE may notify the other device (through network signaling) that the call is ending due to a dead zone. At block 912, the UE may recommend ending or disconnecting the call, for example, by providing a user interface element to the user to end the call.

[0121] In response to the unavailability duration being less than the threshold, at block 914, the UE may send a request for extension of timeout (e.g., an RTP timer) to the network.

[0122] At block 916, the timeout may be delayed. The UE and network may respectively store context associated with the network to resume the connection at a later time. The network may store the RAT and UE state (e.g., an RRC state). The information may be stored for the duration of unavailability. At block 928, the other device may be provided with signaling from the network causing the other device to display a notification that the call is temporarily paused and may resume soon (e.g., based on the duration of unavailability which may also be presented in the notification). At block 918, the UE may store the sequence number of the last RTP packet that is in the RTP buffer of the UE, which may also be used to restore the active call with the other device (for example, by resuming the consumption of the buffer at the stored sequence number).

[0123] At block 920, if the UE exits the dead zone, it may proceed to blocks 926 and block 930. At block 930, the UE may de-activate the call extension mode internally. The UE may also proceed to block 932 and notify the other device that the UE is out of the dead zone. At block 926, the UE and network work together to resume the call with the other device using the last RTP sequence number and last active RAT. In this manner, the return to the active call picks up where it last left off.

[0124] If the UE does not exit the dead time at block 920, it may proceed to block 922 and wait for the extension of the timeout to expire. Once that happens, the UE and network proceed to block 924 in which the legacy release of the network and UE resources regarding the active call are performed. For example, the UE and network may release the context (e.g., RTP SN, RTP buffer, UE state information, last RAT, etc.).

[0125] At block 926, the UE and network may resume the call between the UE and the other device, with the last RTP sequence number and with the last active RAT. Some of the operations are optional described are optional.

[0126] FIG. 10 illustrates an example table for inferring a dead zone based on one or more conditions, according to an aspect. As described, a UE may determine that it will enter a dead zone based on one or more conditions such as the UE location (e.g., latitude and longitude of the UE with respect to a map), the time of day, the day of week, a baseband pattern, sensed motion data, sensed air pressure, or audio quality.

[0127] For example, a UE may include logic that leverages ‘Core Motion’ and / or on-device learning to infer an upcoming unavailability duration of the UE is to occur. Core Motion mayinclude a framework accesses and processes data from device sensors such as motion and environment-related information from accelerometers, gyroscopes, pedometers, magnetometers, and / or barometers, to determine a device's environment or change in environment. With this processing of the sensor data, a UE may detect what a user is doing, such as driving, running, cycling, or if the user has entered a vehicle, an elevator, a tunnel, or other enclosed space.

[0128] A baseband pattern may refer to a signal measurement which fluctuates consistently in response to the user's environment. For example, if each time a user enters an elevator and loses a signal, the signal of the network has a distinct profile (prior to the loss of communication), this measured signal pattern may be used to predict when the UE is entering that elevator or a similar dead zone. The UE may detect a clear signal pattern (e.g., RSRQ, RS SI, or RSRP) drop while entering an elevator, tunnel, or other network dead zone. A UE may experience a known pattern of a single drop which could train a model to predict the potential drop. This pattern could be correlated with other metrics such as device activity pattern, time of day, sensed environment data (e.g., Core motion) to predict when the UE will enter the dead zone, and for how long the UE will be in the dead zone.

[0129] In an aspect, any one or combination of the inputs shown in table 1002 may be used as input to train a machine learning model (e.g., an artificial neural network) and to predict when the UE will enter the network dead zone, and for how long.

[0130] FIG. 11 illustrates examples for managing call and data based on inferring a dead zone condition, according to an aspect. Tables 1102 and 1104 show inputs for a UE to use to determine that the UE is to enter a network dead zone, for how long, and whether or not to tear down a call or data session. Generally, the UE may use logic (e.g., an algorithm such as a machine learning algorithm) to train parameters to learn correlations between past sets of these inputs and UE unavailability duration.

[0131] FIG. 1102 shows an example of how, based on the time of day, day of week, location of the UE, baseband pattern, sensed environment or movement of the UE (e.g., using sensors 606), the UE may predict that the UE is to enter a dead zone (e.g., immediately or imminently) for an unavailability duration of ‘x’ seconds. In response, the UE may save context relating to an active call or active data session, or tear this context down (e.g., releasing this information from memory).

[0132] For example, if the UE predicts that the UE is driving into a parking lot for 90 seconds or greater (e.g., for a time greater than a threshold duration), the UE may, in response, tear downan active call (e.g., by disconnecting and releasing related resources). In such a case, the UE may still, however, save the context for an active data session that is interrupted.

[0133] Similar scenarios are shown with respect to table 1104. For example, based on the UE barometric pressure increasing, or water detection, or both, the UE may predict that the UE is diving deeper in water. In response to this prediction, the UE may tear down active calls or active data sessions.

[0134] In an example, the UE may predict that the unavailability period will include a repetitive pattern of communication loss with the network (e.g., in the case of a high-speed train). The US may, in such a case, tear down the context related to an active call session, but store the context for an active data session.

[0135] Other examples are also disclosed in table 1104. Further, these examples are not exhaustive and are meant to be illustrative. For example, the UE logic may train parameters to recognize that at 3pm on Saturday if the UE is within location (e.g., at latitude ‘X’ and longitude ‘ Y’), and sensors sense a change in light or pressure or humidity of ‘x’, then the UE is predicted to experience a loss of network communication for ‘y’ seconds. Examples of which combinations may predicate a network dead zone may vary depending on UE learned behavior of a given user, and may vary from user to user and over time, depending on the user's behavior with a given UE.

[0136] FIG. 12 illustrates an example sequence diagram table for performing an efficient recovery based on an expected unavailability period, according to an aspect.

[0137] A UE 1202 may be in communication with a network (e.g., network 604) which may comprise network components such as, for example, Access & Mobility Management Function (AMF) control plane 1204. AMF 1204 handles connection and mobility management tasks for a network, and serves as an interface between the UE and the network for session management.

[0138] At block 1206, the UE registers in standalone access (SA) with both UE and the NW negotiating the support of the ‘unavailability period’ . Support for unavailability period is defined in release 17 of 3GPP as: “If the UE and network support unavailability period and an event is triggered in the UE making the UE unavailable for a certain period of time, the UE may store its 5GMM and 5GSM context in USIM or non-volatile memory to be able to reuse it after the unavailability period.” How the UE stores its contexts may be UE implementation specific.

[0139] At block 1208, the UE determines that it may enter a network dead zone (which may also be referred to as a glitch zone) in which the UE may recover from in a short duration, for example, within less than a threshold duration of time. In response, the UE may send aregistration request with its predicted unavailability duration. This may be a request to extend a time out (e.g., RTP timer duration). In response, the AMF 1204 may accept the registration request to extend the time out and respond accordingly with a registration accept signal. This signal may indicate that the RTP timer (e.g., T3412) has been extended by the unavailability duration.

[0140] At block 1212 the UE may store the context in memory. Similarly, at block 1210, the network may store the context for the UE in memory.

[0141] At 1214, the UE 1202 may exit the network dead zone, prior to the expiration of the unavailability duration (e.g., before the time out expires). In response, the UE and network may perform signaling (e.g., registration request and registration accept) with the stored context, respectively, to restore the call and / or data session. At block 1216, the 5GMM and / or 5GSM context is restored and the call or data session is restored successfully.

[0142] If the UE does not exit the network dead zone within the extended time (as requested through the registration request), the session may time out and the call or data session may come to an end without a graceful restoration.

[0143] FIG. 13 illustrates an example sequence diagram for de-registering from the network in response to determining an expected unavailability period, according to an aspect.

[0144] UE 1302 may be in communication with a network (e.g., network 604) which may include an AMF component 1304. At block 1306, the UE may be registered in SA. The UE and network may negotiate the support of an unavailability period, with back and forth signaling. Support for the unavailability period may vary from one UE to another, or based on network position, or both.

[0145] At block 1308, the UE determines that it may enter a network dead zone, and in this case, the unavailability duration is predicted to be greater than a threshold duration. In response, the UE may send a de-registration request that includes in it the unavailability duration of time as predicted by UE 1302. The network may respond by sending a de-registration accept message to the UE 1302. In such a case, the UE 1302 and network may also refrain from storing the context associated with communication between the UE and the network. For example, the UE, the network, or both, may release resources related to the current context of the UE and the network (e.g., call or data session information, RTP packets, etc.).

[0146] Table 1 below shows an example of how the UE may request for different extension of time based on the UEs prediction of the network dead zone. Based on how long the UE predicts it will be in the network dead zone or based on how the UE identifies the type of dead zone (e.g.,a lift, tunnel, etc.), the UE can extend the RTP timeout accordingly to save the call. Different dead zones or unavailability durations may be accommodated by an appropriate extension of time. For example, the requested extension of time may be the same or greater than the predicted unavailability duration of the UE.TABLE 1

[0147] FIG. 14 illustrates an example user equipment with multiple antennae operation during a network unavailability period, according to an aspect.

[0148] In a sudden move to a network dead zone like a lift, tunnel, etc., generally two situations may occur: 1. The UE is in a DL Limited Scenario in which case the other party on the call with the UE can hear but the party with the UE cannot, or 2. The UE is in UL Limited Scenario in which case the other party on the call with the UE cannot hear but the party in the network dead zone can hear.

[0149] In the DL Limited scenario, if DL packets are not received for a threshold of time (e.g., 10 secs), and UL is not limited, the real time protocol (RTP) is likely to time out for the UE in the dead zone, resulting in a dropped call. Since, UL is not limited in this scenario, the UE may, at the same time, send a message (e.g., an IP Multimedia Subsystem (IMS) message) through the network to the other device, indicating the other user to wait for certain time = extended RTP timer which can be displayed in UI to other end user.

[0150] To mitigate UL limited scenario in a dead zone, due to the fast and sudden communication loss with the network, automatic transmit diversity (ATD) is less effective as RSRP of each antenna fluctuates more than usual and a UE may have weaker transmission strength resulting in UL limitation or drop.

[0151] When the UE enters the network dead zone while in an active session (e.g., a call session), three scenarios are considered: a) UE is in pocket but unheld (free space); b) UE is held in hand; or c) UE is held in hand while pressed against the user's head. Under ‘a’, the UE may let normal operation and triggering of ATD given that UE is in free space. Under ‘b’ and / or ‘c’,the UE may use upper hemisphere antennas (e.g., antenna ‘C’ an ‘D’), given that the UE is typically gripped so that lower antennas A, B are covered by the hand of user 1404, which degrades Tx performance which could result in reduced UL or a call drop.

[0152] UE 1402 may sense the current grip state using one or more sensors (e.g., sensors 606) of the UE. The one or more sensors may include a microphone, an accelerometer, a gyroscope, the RF transceiver of the UE, a proximity sensor, a camera, or other sensors. Based on the sensed information, the UE may determine the orientation of the device, signal strength / quality, nearby objects, etc., from which the UE may infer whether the UE is gripped and or pressed against the user's head.

[0153] Table 2 below shows how a UE may perform different operations based on a priority designation of the interrupted application. For example, the UE may categorize live calls with other devices under a first priority (Pl), live streaming applications with a second priority (P2), and other applications (non-live call, non-live streaming) such as social media application with a third priority (P3). Live calls may include conferencing applications such as, for example, Webex, Zoom, a standard voice call, etc. Based on the priority of the session that is interrupted by the dead zone, the UE may perform different restoration operations, as indicated in table 2 below.TABLE 2

[0154] There are a number of example embodiments described herein.

[0155] Example l is a method performed by a UE in communication with a network, including: in response to determining that the UE is to enter a dead zone of the network, sending, to the network, an unavailability duration of time that is associated with the dead zone, and storing a context associated with the network; and restoring the communication to the network based on the stored context when the UE exits the dead zone of the network.

[0156] Example 2 is the method of Example 1 that may optionally include that storing the context includes storing a 5G mobility management (5GMM) context and a 5G session management (5 GSM) context in memory of the UE.

[0157] Example 3 is the method of Example 1 that may optionally include that storing the context includes storing packet data units (PDUs) and a radio resource control (RRC) state of the UE as the context.

[0158] Example 4 is the method of Example 1 that may optionally include that sending the unavailability duration of time includes sending a request for extension of a real time protocol (RTP) timer for the unavailability duration of time, and storing the context includes saving a sequence number (SN) associated with a last RTP packet in a buffer of the UE.

[0159] Example 5 is the method of Example 1 that may optionally include that restoring the communication to the network with the stored context resumes a call or data session of the UE that was interrupted by the dead zone.

[0160] Example 6 is the method of Example 1 that may optionally include that in response to the UE exiting the dead zone prior to expiration of the unavailability duration of time, restoring the communication to the network with the stored context.

[0161] Example 7 is the method of Example 1 that may optionally include, in response to determining that unavailability duration of time associated with the dead zone is greater than a threshold, de-registering from the network.

[0162] Example 8 is the method of Example 7 that may optionally include that de-registering from the network includes sending a de-registration request that includes an indication of the unavailability duration of time.

[0163] Example 9 is the method of Example 1 that may optionally include that determining that the UE is to enter the dead is based on one or more conditions including at least one of: a location of the UE, a time of day, a day of week, a baseband pattern, an accelerometer, a gyroscope, a pedometer, a magnetometer, or a barometer.

[0164] Example 10 is the method of Example 9 that may optionally include that determining that the UE is to enter the dead zone includes applying a machine learning model to the one or more conditions to infer that the UE is to enter the dead zone.

[0165] Example 11 is the method of Example 1 that may optionally include, while the UE is in the dead zone, in response to the UE being gripped, using upper hemisphere antennas for uplink transmission, and in response to the UE being ungripped, performing an automatic transmit diversity (ATD) for a plurality of antennas of the UE.

[0166] Example 12 is a method, performed by a network in communication with a user equipment (UE), comprising: receiving a registration request from the UE, the registration request including an unavailability duration of time associated with a dead zone of the network; sending, to the UE, a registration accept message; storing a context associated with the UE; and restoring the communication to with UE based on the context when the UE exits the dead zone of the network.

[0167] Example 13 is the method of Example 12 that may optionally include, in response to receiving the registration request from the UE, extending a time out associated with an active session of the UE for at least the unavailability duration of time.

[0168] Example 14 is the method of Example 12 that may optionally include that, in response to the UE being in a call with a second UE over the network when the registration request is received from the UE, sending the unavailability duration of time to the second UE.

[0169] Example 15 is the method of Example 14 that may optionally include that sending the unavailability duration of time to the second UE causes the second UE to present a notification indicating that the UE is unavailable.

[0170] Example 16 is the method of Example 12 that may optionally include that receiving a de-regi strati on request from the UE, the de-registration request including the unavailability duration of time; and sending a de-registration accept to the UE.

[0171] Example 17 is the method of Example 16 that may optionally include that in response to receiving the de-registration request from the UE, the network refrains from storing the context associated with the UE.

[0172] Example 18 is the method of Example 12 that may optionally include that receiving the registration request from the UE includes receiving a request for extension of a real time protocol (RTP) timer for the unavailability duration of time.

[0173] Example 19 is the method of Example 18 that may optionally include that sending the registration accept message includes extending the RTP timer for the unavailability duration of time, and sending to the UE, an acceptance that the RTP timer is extended for the unavailability duration of time.

[0174] Example 20 is an apparatus, comprising a processor coupled to non-transitory computer memory storing instructions that, when executed by the processor, cause the processor to perform the method of any one of example 1 to example 19.

[0175] Example 21 is a UE configured to perform the operations of the method of any one of example 1 to example 11.

[0176] Example 22 is a baseband processor configured to perform the operations of the method of any one of example 1 to example 11.

[0177] Example 23 is a network configured to perform the operations of the method of any one of example 12 to example 19.

[0178] Example 24 is a baseband processor configured to perform the operations of the method of any one of example 12 to example 19.

[0179] Example 25 is a non-transitory computer readable memory storing instructions that, when executed by a processor, causes performance of the method of any one of example 1 to example 19.

[0180] Portions of what was described above may be implemented with logic circuitry such as a dedicated logic circuit or with a microcontroller or other form of processing core that executes program code instructions. Thus, processes taught by the discussion above may be performed with program code such as machine-executable instructions that cause a machine that executes these instructions to perform certain functions. In this context, a “machine” may be a machine that converts intermediate form (or “abstract”) instructions into processor specific instructions (e.g., an abstract execution environment such as a “virtual machine” (e.g., a Java Virtual Machine), an interpreter, a Common Language Runtime, a high-level language virtual machine, etc.), and / or, electronic circuitry disposed on a semiconductor chip (e.g., “logic circuitry” implemented with transistors) designed to execute instructions such as a general-purpose processor and / or a special-purpose processor. Processes taught by the discussion above may also be performed by (in the alternative to a machine or in combination with a machine) electronic circuitry designed to perform the processes (or a portion thereof) without the execution of program code.

[0181] The present invention also relates to an apparatus for performing the operations described herein. This apparatus may be specially constructed for the required purpose, or it may comprise a general -purpose computer selectively activated or reconfigured by a computer program stored in the computer. Such a computer program may be stored in a computer readable storage medium, such as, but is not limited to, any type of disk including floppy disks, optical disks, CD-ROMs, and magnetic-optical disks, read-only memories (ROMs), RAMs, EPROMs, EEPROMs, magnetic or optical cards, or any type of media suitable for storing electronic instructions, and each coupled to a computer system bus.

[0182] A machine-readable medium includes any mechanism for storing or transmitting information in a form readable by a machine (e.g., a computer). For example, a machine-readable medium includes read only memory (“ROM”); random access memory (“RAM”); magnetic disk storage media; optical storage media; flash memory devices; etc.

[0183] In any of the examples described, a processor may include a baseband processor (also known as baseband radio processor, BP, or BBP) is a device (a chip or part of a chip) in a network interface that manages radio functions, such as communicating (e.g., TX and RX) over an antenna.

[0184] An article of manufacture may be used to store program code. An article of manufacture that stores program code may be embodied as, but is not limited to, one or more memories (e.g., one or more flash memories, random access memories (static, dynamic, or other)), optical disks, CD-ROMs, DVD ROMs, EPROMs, EEPROMs, magnetic or optical cards or other type of machine-readable media suitable for storing electronic instructions. Program code may also be downloaded from a remote computer (e.g., a server) to a requesting computer (e.g., a client) by way of data signals embodied in a propagation medium (e.g., via a communication link (e.g., a network connection)).

[0185] The preceding detailed descriptions are presented in terms of algorithms and symbolic representations of operations on data bits within a computer memory. These algorithmic descriptions and representations are the tools used by those skilled in the data processing arts to most effectively convey the substance of their work to others skilled in the art. An algorithm is here, and generally, conceived to be a self-consistent sequence of operations leading to a desired result. The operations are those requiring physical manipulations of physical quantities. Usually, though not necessarily, these quantities take the form of electrical or magnetic signals capable of being stored, transferred, combined, compared, and otherwisemanipulated. It has proven convenient at times, principally for reasons of common usage, to refer to these signals as bits, values, elements, symbols, characters, terms, numbers, or the like.

[0186] It should be kept in mind, however, that all of these and similar terms are to be associated with the appropriate physical quantities and are merely convenient labels applied to these quantities. Unless specifically stated otherwise as apparent from the above discussion, it is appreciated that throughout the description, discussions utilizing terms such as “transmitting”, “sending”, “selecting,” “determining,” “receiving,” “forming,” “grouping,” “aggregating,” “generating,” “removing,” or the like, refer to the action and processes of a computer system, or similar electronic computing device, that manipulates and transforms data represented as physical (electronic) quantities within the computer system's registers and memories into other data similarly represented as physical quantities within the computer system memories or registers or other such information storage, transmission or display devices.

[0187] The processes and displays presented herein are not inherently related to any particular computer or other apparatus. Various general -purpose systems may be used with programs in accordance with the teachings herein, or it may prove convenient to construct a more specialized apparatus to perform the operations described. The required structure for a variety of these systems will be evident from the description below. In addition, the present invention is not described with reference to any particular programming language. It will be appreciated that a variety of programming languages may be used to implement the teachings of the invention as described herein.

[0188] 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.

[0189] The foregoing discussion merely describes some exemplary aspects of the present invention. One skilled in the art will readily recognize from such discussion, the accompanying drawings and the claims that various modifications can be made without departing from the spirit and scope of the invention.

Claims

CLAIMSWhat is claimed is:

1. A method, performed by a user equipment (UE) in communication with a network, comprising: in response to determining that the UE is to enter a dead zone of the network, sending, to the network, an unavailability duration of time that is associated with the dead zone, and storing a context associated with the network; and restoring the communication to the network based on the stored context when the UE exits the dead zone of the network.

2. The method of claim 1, wherein storing the context includes storing a 5G mobility management (5GMM) context and a 5G session management (5GSM) context in memory of the UE.

3. The method of claim 1, wherein storing the context includes storing packet data units (PDUs) and a radio resource control (RRC) state of the UE as the context.

4. The method of claim 1, wherein sending the unavailability duration of time includes sending a request for extension of a real time protocol (RTP) timer for the unavailability duration of time, and storing the context includes saving a sequence number (SN) associated with a last RTP packet in a buffer of the UE.

5. The method of claim 1, wherein restoring the communication to the network with the stored context resumes a call or data session of the UE that was interrupted by the dead zone.

6. The method of claim 1, wherein in response to the UE exiting the dead zone prior to expiration of the unavailability duration of time, restoring the communication to the network with the stored context.

7. The method of claim 1, further comprising in response to determining that unavailability duration of time associated with the dead zone is greater than a threshold, de-registering from the network.

8. The method of claim 7, wherein de-registering from the network includes sending a deregistration request that includes an indication of the unavailability duration of time.

9. The method of claim 1, wherein determining that the UE is to enter the dead is based on one or more conditions including at least one of: a location of the UE, a time of day, a day of week, a baseband pattern, an accelerometer, a gyroscope, a pedometer, a magnetometer, or a barometer.

10. The method of claim 9, wherein determining that the UE is to enter the dead zone includes applying a machine learning model to the one or more conditions to infer that the UE is to enter the dead zone.

11. The method of claim 1, further comprising: while the UE is in the dead zone, in response to the UE being gripped, using upper hemisphere antennas for uplink transmission, and in response to the UE being ungripped, performing an automatic transmit diversity (ATD) for a plurality of antennas of the UE.

12. A method, performed by a network in communication with a user equipment (UE), comprising: receiving a registration request from the UE, the registration request including an unavailability duration of time associated with a dead zone of the network; sending, to the UE, a registration accept message; storing a context associated with the UE; and restoring the communication to with UE based on the context when the UE exits the dead zone of the network.

13. The method of claim 12, further comprising: in response to receiving the registration request from the UE, extending a time out associated with an active session of the UE for at least the unavailability duration of time.

14. The method of claim 12, further comprising: in response to the UE being in a call with a second UE over the network when the registration request is received from the UE, sending the unavailability duration of time to the second UE.

15. The method of claim 14, wherein sending the unavailability duration of time to the second UE causes the second UE to present a notification indicating that the UE is unavailable.

16. The method of claim 12, further comprising: receiving a de-regi strati on request from the UE, the de-registration request including the unavailability duration of time; and sending a deregistration accept to the UE.

17. The method of claim 16, wherein in response to receiving the de-registration request from the UE, the network refrains from storing the context associated with the UE.

18. The method of claim 12, wherein receiving the registration request from the UE includes receiving a request for extension of a real time protocol (RTP) timer for the unavailability duration of time.

19. The method of claim 18, wherein sending the registration accept message includes extending the RTP timer for the unavailability duration of time, and sending to the UE, an acceptance that the RTP timer is extended for the unavailability duration of time.

20. An apparatus, comprising a processor coupled to non-transitory computer memory storing instructions that, when executed by the processor, cause the processor to perform the method of any one of claim 1 to claim 19.

21. A UE configured to perform the operations of the method of any one of claim 1 to claim 11.

22. A baseband processor configured to perform the operations of the method of any one of claim 1 to claim 11.

23. A network configured to perform the operations of the method of any one of claim 12 to claim 19.

24. A baseband processor configured to perform the operations of the method of any one of claim 12 to claim 19.

25. A non-transitory computer readable memory storing instructions that, when executed by a processor, causes performance of the method of any one of claim 1 to claim 19.

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