WO2021226987A1 - Récupération d'un décrochage de données dans des systèmes de communication sans fil - Google Patents

Récupération d'un décrochage de données dans des systèmes de communication sans fil Download PDF

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Publication number
WO2021226987A1
WO2021226987A1 PCT/CN2020/090447 CN2020090447W WO2021226987A1 WO 2021226987 A1 WO2021226987 A1 WO 2021226987A1 CN 2020090447 W CN2020090447 W CN 2020090447W WO 2021226987 A1 WO2021226987 A1 WO 2021226987A1
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WIPO (PCT)
Prior art keywords
sequence number
operating
convergence protocol
data convergence
packet data
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PCT/CN2020/090447
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English (en)
Inventor
Hao Zhang
Pan JIANG
Chaofeng HUI
Fojian ZHANG
Yuankun ZHU
Jian Li
Tianya LIN
Xiuqiu XIA
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Qualcomm Incorporated
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Priority to PCT/CN2020/090447 priority Critical patent/WO2021226987A1/fr
Publication of WO2021226987A1 publication Critical patent/WO2021226987A1/fr

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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W36/00—Hand-off or reselection arrangements
    • H04W36/24—Reselection being triggered by specific parameters
    • H04W36/30—Reselection being triggered by specific parameters by measured or perceived connection quality data
    • H04W36/305—Handover due to radio link failure
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W76/00—Connection management
    • H04W76/10—Connection setup
    • H04W76/19—Connection re-establishment
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W88/00—Devices specially adapted for wireless communication networks, e.g. terminals, base stations or access point devices
    • H04W88/02—Terminal devices
    • H04W88/06—Terminal devices adapted for operation in multiple networks or having at least two operational modes, e.g. multi-mode terminals

Definitions

  • the following relates generally to wireless communications and more specifically to recovering from a data stall in wireless communications systems.
  • Wireless communications systems are widely deployed to provide various types of communication content such as voice, video, packet data, messaging, broadcast, and so on. These systems may be capable of supporting communication with multiple users by sharing the available system resources (e.g., time, frequency, and power) .
  • Examples of such multiple-access systems include fourth generation (4G) systems such as Long Term Evolution (LTE) systems, LTE-Advanced (LTE-A) systems, or LTE-APro systems, and fifth generation (5G) systems which may be referred to as New Radio (NR) systems.
  • 4G systems such as Long Term Evolution (LTE) systems, LTE-Advanced (LTE-A) systems, or LTE-APro systems
  • 5G systems which may be referred to as New Radio (NR) systems.
  • a wireless multiple-access communications system may include one or more base stations or one or more network access nodes, each simultaneously supporting communication for multiple communication devices, which may be otherwise known as user equipment (UE) .
  • Some communication devices may experience a latency or an interruption in wireless communications when camping on a cell. For example, some communication devices may experience a stall in transmitting or receiving information (e.g., control or data) when camping on an LTE cell or a 5G NR cell, or both.
  • a communication device which may be otherwise known as user equipment (UE) to support recovering from a delay or an interruption in wireless communications when camping on a cell in a wireless communications system.
  • the UE may be configured to receive a packet including a packet data convergence protocol (PDCP) protocol data unit (PDU) (also referred to as a service data unit) .
  • PDCP packet data convergence protocol
  • PDU protocol data unit
  • the UE may determine that a PDCP sequence number associated with the received PDCP PDU satisfies a PDCP sequence number hopping threshold, and determine a radio link failure condition with a cell the UE is camped on based on the PDCP sequence number satisfying the PDCP sequence number hopping threshold.
  • the UE may switch from operating in a first radio access technology (RAT) to operating in a second RAT based on the determining. For example, the UE may camp on a 5G NR cell and switch to camp on a 4G LTE cell. Once the UE is camped on the 4G LTE cell, the UE may initiate a packet-switched data transfer, such that the UE may receive information (e.g., control or data, or both) while camping on the 4G LTE cell. The UE may therefore recover from a delay or an interruption in wireless communications (e.g., a data stall) when camping on a cell associated with a radio link failure in a wireless communications system.
  • the described techniques may, as a result, also include features for improvements to wireless communications and, in some examples, may promote low power consumption, as well as high reliability and low latency wireless communications, among other benefits.
  • a method of wireless communication at a UE may include receiving a packet associated with a PDCP sequence number, determining that the PDCP sequence number satisfies a PDCP sequence number hopping threshold, determining a radio link failure condition based on the PDCP sequence number satisfying the PDCP sequence number hopping threshold, and switching from operating in a first RAT to operating in a second RAT based on the radio link failure condition.
  • the apparatus may include a processor, memory coupled with the processor, and instructions stored in the memory.
  • the instructions may be executable by the processor to cause the apparatus to receive a packet associated with a PDCP sequence number, determine that the PDCP sequence number satisfies a PDCP sequence number hopping threshold, determine a radio link failure condition based on the PDCP sequence number satisfying the PDCP sequence number hopping threshold, and switch from operating in a first RAT to operating in a second RAT based on the radio link failure condition.
  • the apparatus may include means for receiving a packet associated with a PDCP sequence number, determining that the PDCP sequence number satisfies a PDCP sequence number hopping threshold, determining a radio link failure condition based on the PDCP sequence number satisfying the PDCP sequence number hopping threshold, and switching from operating in a first RAT to operating in a second RAT based on the radio link failure condition.
  • a non-transitory computer-readable medium storing code for wireless communication at a UE is described.
  • the code may include instructions executable by a processor to receive a packet associated with a PDCP sequence number, determine that the PDCP sequence number satisfies a PDCP sequence number hopping threshold, determine a radio link failure condition based on the PDCP sequence number satisfying the PDCP sequence number hopping threshold, and switch from operating in a first RAT to operating in a second RAT based on the radio link failure condition.
  • Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for switching from operating in a standalone mode to operating in a non-standalone mode based on determining that the PDCP sequence number associated with the received packet satisfies the PDCP sequence number hopping threshold.
  • Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for transmitting a TAU request message to a second base station based on switching from operating in the standalone mode to operating in the non-standalone mode, receiving a TAU response message from the second base station based on the transmitted TAU request message, , and where switching from operating in the first RAT to operating in the second RAT may be based on the received TAU response message from the second base station.
  • Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for TAU response message includes a TAU accept.
  • the TAU request message includes dual-connectivity new radio capability information.
  • Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for camping on a cell associated with the second base station while operating in the non-standalone mode.
  • Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for transmitting a service request message to the second base station for packet-switched data transfer based on the received TAU response message from the second base station, and transferring packet-switched data between the UE and the second base station based on the transmitted service request message.
  • receiving the packet may include operations, features, means, or instructions for receiving the packet from a first base station associated with the first RAT.
  • Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for camping on a cell associated with the first base station while operating in a standalone mode.
  • determining that the PDCP sequence number associated with the received packet satisfies the PDCP sequence number hopping threshold may include operations, features, means, or instructions for determining a difference between the PDCP sequence number associated with the received packet and a previous PDCP sequence number associated with a previously received packet, and determining that the difference satisfies the PDCP sequence number hopping threshold.
  • determining that the difference satisfies the PDCP sequence number hopping threshold may include operations, features, means, or instructions for determining that the difference may be greater than the PDCP sequence number hopping threshold.
  • the received packet corresponds to a first slot and the previously received packet corresponds to a second slot preceding the first slot.
  • switching from operating in the first RAT to operating in the second RAT may include operations, features, means, or instructions for operating in the second RAT while operating in a non-standalone mode.
  • Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for operating exclusively in the second RAT based on switching from operating in the first RAT to operating in the second RAT.
  • Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for updating a value of the PDCP sequence number hopping threshold based on triggering a TAU to a cell associated with the second RAT.
  • updating the value of the PDCP sequence number hopping threshold may include operations, features, means, or instructions for increasing the value of the PDCP sequence number hopping threshold based on a defined value.
  • the packet includes a NR-type PDCP service data unit.
  • the first RAT includes 5G NR and the second RAT includes 4G LTE.
  • FIGs. 1 and 2 illustrate examples of wireless communications systems that support recovering from a data stall in wireless communications systems in accordance with aspects of the present disclosure.
  • FIG. 3 and 4 illustrate examples of process flows that support recovering from a data stall in wireless communications systems in accordance with aspects of the present disclosure.
  • FIGs. 5 and 6 show diagrams of devices that support recovering from a data stall in wireless communications systems in accordance with aspects of the present disclosure.
  • FIG. 7 shows a diagram of a user equipment (UE) communications manager that supports recovering from a data stall in wireless communications systems in accordance with aspects of the present disclosure.
  • UE user equipment
  • FIG. 8 shows a diagram of a system including a device that supports recovering from a data stall in wireless communications systems in accordance with aspects of the present disclosure.
  • FIGs. 9 through 11 show flowcharts illustrating methods that support recovering from a data stall in wireless communications systems in accordance with aspects of the present disclosure.
  • Some wireless communication systems may include communication devices, such as user equipments (UEs) and base stations, for example, eNodeBs (eNBs) , next-generation NodeBs or giga-NodeBs (either of which may be referred to as a gNB) that may support multiple radio access technologies.
  • UEs user equipments
  • base stations for example, eNodeBs (eNBs) , next-generation NodeBs or giga-NodeBs (either of which may be referred to as a gNB) that may support multiple radio access technologies.
  • radio access technologies include 4G systems such as Long Term Evolution (LTE) systems and fifth generation (5G) systems which may be referred to as New Radio (NR) systems.
  • LTE Long Term Evolution
  • 5G fifth generation
  • NR New Radio
  • the UEs may, in some cases, experience a latency or an interruption in wireless communications when camping on a cell.
  • the UEs may experience a delay or an interruption in transmitting or receiving information (e.g., control or data, or both) when camping on a 4G LTE cell or a 5G NR cell, or both.
  • the base stations may provide communication coverage via one or more cells, for example a macro cell, a small cell, a hot spot, or other types of cells, or any combination thereof.
  • the term cell may refer to a logical communication entity used for communication with the base stations (e.g., over a carrier) and may be associated with an identifier for distinguishing neighboring cells (e.g., a physical cell identifier (PCID) , a virtual cell identifier (VCID) , or others) .
  • PCID physical cell identifier
  • VCID virtual cell identifier
  • the UEs may receive multiple protocol data units (PDUs) .
  • Each PDU may include a protocol data convergence protocol (PDCP) sequence number.
  • the UEs may process the PDUs according to the PDCP sequence number.
  • the UEs may use the PDCP sequence number to deliver each PDU in a correct order to higher layers (e.g., a radio resource control (RRC) layer, a PDCP layer, a radio link control (RLC) layer, etc. ) of a protocol stack of the UEs.
  • RRC radio resource control
  • RLC radio link control
  • the UEs may experience a stall in reception of the PDUs, and thereby may experience reduced reliability and increased latency for reception of data carried in the PDUs.
  • the UEs may be configured to support recovering from a stall in reception of PDUs (which may be NR-type PDCP) by determining that a PDCP sequence number hopping threshold has been satisfied. Because each PDU corresponds to a PDCP sequence number, the UEs may improve efficiency for detecting a stall in reception of the PDUs using the PDCP sequence number hopping threshold. That is, PDCP packets dropped out of sequence (e.g., out-of-window (OOW) of a receiver of the UEs) and data still issue happens. In other words, the UEs may determine a radio link failure condition based on the PDCP packets dropping out of sequence.
  • PDUs which may be NR-type PDCP
  • the UEs may receive PDUs while camping on a 5G NR cell, and upon detecting a data stall event (e.g., based on a sequence number of a received PDU satisfying a PDCP sequence number hopping threshold) , the UEs may switch from camping on the 5G NR cell to camping on a 4G LTE cell to reduce latency and improve reliability for PDU reception at the UEs.
  • An original equipment manufacturer (OEM) may report the data stall even when the UEs camp on a cell (e.g., a 5G NR cell, 4G LTE cell) and the PDCP sequence number hopping threshold is satisfied.
  • OEM original equipment manufacturer
  • the UEs may trigger a data transfer operation, such that the UEs may continue to receive data (i.e., PDUs) from the 4G LTE cell and thereby reducing latency and improving user experience.
  • the UEs may switch cells based at least in part on changing a tracking area procedure.
  • the UEs may connect and exchange tracking area update (TAU) messages with the 4G LTE cell as part of registering or re-registering with the 4G LTE cell during the cell switching.
  • the exchanged TAU messages may include a TAU update request message and a TAU update response message (e.g., a TAU update accept) .
  • the TAU update request message may include dual-connectivity NR capability information.
  • the UEs may inform the 4G LTE cell about a geolocation of the UEs in order to facilitate network services to the UEs, as well as to facilitate connecting to the 4G LTE cell.
  • the UEs may perform a tracking area procedure before camping on the new cell (i.e., the 4G LTE cell) , which may be in a different tracking area.
  • the techniques employed by the UEs may provide benefits and enhancements to the operation of the UEs.
  • operations performed by the UEs may provide improvements to wireless communications.
  • configuring the UEs to recover from a stall in wireless communications when camping on cells in wireless communications systems may support improvements to power consumption, spectral efficiency, and, in some examples, may promote high reliability and low latency wireless communications, among other benefits.
  • aspects of the disclosure are initially described in the context of wireless communications systems. Aspects of the disclosure are further illustrated by and described with reference to apparatus diagrams, system diagrams, and flowcharts that relate to recovering from a data stall in wireless communications systems.
  • FIG. 1 illustrates an example of a wireless communications system 100 that supports recovering from a data stall in wireless communications systems in accordance with aspects of the present disclosure.
  • the wireless communications system 100 may include one or more base stations 105, one or more UEs 115, and a core network 130.
  • the wireless communications system 100 may be a Long Term Evolution (LTE) network, an LTE-Advanced (LTE-A) network, an LTE-APro network, or a New Radio (NR) network.
  • LTE Long Term Evolution
  • LTE-A LTE-Advanced
  • LTE-APro LTE-APro
  • NR New Radio
  • the wireless communications system 100 may support enhanced broadband communications, ultra-reliable (e.g., mission critical) communications, low latency communications, communications with low-cost and low-complexity devices, or any combination thereof.
  • ultra-reliable e.g., mission critical
  • the base stations 105 may be dispersed throughout a geographic area to form the wireless communications system 100 and may be devices in different forms or having different capabilities.
  • the base stations 105 and the UEs 115 may wirelessly communicate via one or more communication links 125.
  • Each base station 105 may provide a coverage area 110 over which the UEs 115 and the base station 105 may establish one or more communication links 125.
  • the coverage area 110 may be an example of a geographic area over which a base station 105 and a UE 115 may support the communication of signals according to one or more radio access technologies.
  • the UEs 115 may be dispersed throughout a coverage area 110 of the wireless communications system 100, and each UE 115 may be stationary, or mobile, or both at different times.
  • the UEs 115 may be devices in different forms or having different capabilities. Some example UEs 115 are illustrated in FIG. 1.
  • the UEs 115 described herein may be able to communicate with various types of devices, such as other UEs 115, the base stations 105, or network equipment (e.g., core network nodes, relay devices, integrated access and backhaul (IAB) nodes, or other network equipment) , as shown in FIG. 1.
  • network equipment e.g., core network nodes, relay devices, integrated access and backhaul (IAB) nodes, or other network equipment
  • the base stations 105 may communicate with the core network 130, or with one another, or both.
  • the base stations 105 may interface with the core network 130 through one or more backhaul links 120 (e.g., via an S1, N2, N3, or other interface) .
  • the base stations 105 may communicate with one another over the backhaul links 120 (e.g., via an X2, Xn, or other interface) either directly (e.g., directly between base stations 105) , or indirectly (e.g., via core network 130) , or both.
  • the backhaul links 120 may be or include one or more wireless links.
  • One or more of the base stations 105 described herein may include or may be referred to by a person having ordinary skill in the art as a base transceiver station, a radio base station, an access point, a radio transceiver, a NodeB, an eNodeB (eNB) , a next-generation NodeB or a giga-NodeB (either of which may be referred to as a gNB) , a Home NodeB, a Home eNodeB, or other suitable terminology.
  • a base transceiver station a radio base station
  • an access point a radio transceiver
  • a NodeB an eNodeB (eNB)
  • eNB eNodeB
  • a next-generation NodeB or a giga-NodeB either of which may be referred to as a gNB
  • gNB giga-NodeB
  • a UE 115 may include or may be referred to as a mobile device, a wireless device, a remote device, a handheld device, or a subscriber device, or some other suitable terminology, where the “device” may also be referred to as a unit, a station, a terminal, or a client, among other examples.
  • a UE 115 may also include or may be referred to as a personal electronic device such as a cellular phone, a personal digital assistant (PDA) , a tablet computer, a laptop computer, or a personal computer.
  • PDA personal digital assistant
  • a UE 115 may include or be referred to as a wireless local loop (WLL) station, an Internet of Things (IoT) device, an Internet of Everything (IoE) device, or a machine type communications (MTC) device, among other examples, which may be implemented in various objects such as appliances, or vehicles, meters, among other examples.
  • the UEs 115 described herein may be able to communicate with various types of devices, such as other UEs 115 that may sometimes act as relays as well as the base stations 105 and the network equipment including macro eNBs or gNBs, small cell eNBs or gNBs, or relay base stations, among other examples, as shown in FIG. 1.
  • the UEs 115 and the base stations 105 may wirelessly communicate with one another via one or more communication links 125 over one or more carriers.
  • the term “carrier” may refer to a set of radio frequency spectrum resources having a defined physical layer structure for supporting the communication links 125.
  • a carrier used for a communication link 125 may include a portion of a radio frequency spectrum band (e.g., a bandwidth part (BWP) ) that is operated according to one or more physical layer channels for a given RAT (e.g., LTE, LTE-A, LTE-A Pro, NR) .
  • a radio frequency spectrum band e.g., a bandwidth part (BWP)
  • BWP bandwidth part
  • Each physical layer channel may carry acquisition signaling (e.g., synchronization signals, system information) , control signaling that coordinates operation for the carrier, user data, or other signaling.
  • the wireless communications system 100 may support communication with a UE 115 using carrier aggregation or multi-carrier operation.
  • a UE 115 may be configured with multiple downlink component carriers and one or more uplink component carriers according to a carrier aggregation configuration.
  • Carrier aggregation may be used with both frequency division duplexing (FDD) and time division duplexing (TDD) component carriers.
  • FDD frequency division duplexing
  • TDD time division duplexing
  • a carrier may also have acquisition signaling or control signaling that coordinates operations for other carriers.
  • a carrier may be associated with a frequency channel (e.g., an evolved universal mobile telecommunication system terrestrial radio access (E-UTRA) absolute radio frequency channel number (EARFCN) ) and may be positioned according to a channel raster for discovery by the UEs 115.
  • E-UTRA evolved universal mobile telecommunication system terrestrial radio access
  • a carrier may be operated in a standalone mode where initial acquisition and connection may be conducted by the UEs 115 via the carrier, or the carrier may be operated in a non-standalone mode where a connection is anchored using a different carrier (e.g., of the same or a different RAT) .
  • the communication links 125 shown in the wireless communications system 100 may include uplink transmissions from a UE 115 to a base station 105, or downlink transmissions from a base station 105 to a UE 115.
  • Carriers may carry downlink or uplink communications (e.g., in an FDD mode) or may be configured to carry downlink and uplink communications (e.g., in a TDD mode) .
  • a carrier may be associated with a particular bandwidth of the radio frequency spectrum, and in some examples the carrier bandwidth may be referred to as a “system bandwidth” of the carrier or the wireless communications system 100.
  • the carrier bandwidth may be one of a number of determined bandwidths for carriers of a particular RAT (e.g., 1.4, 3, 5, 10, 15, 20, 40, or 80 megahertz (MHz) ) .
  • Devices of the wireless communications system 100 e.g., the base stations 105, the UEs 115, or both
  • the wireless communications system 100 may include base stations 105 or UEs 115 that support simultaneous communications via carriers associated with multiple carrier bandwidths.
  • each served UE 115 may be configured for operating over portions (e.g., a sub-band, a BWP) or all of a carrier bandwidth.
  • Signal waveforms transmitted over a carrier may be made up of multiple subcarriers (e.g., using multi-carrier modulation (MCM) techniques such as orthogonal frequency division multiplexing (OFDM) or discrete Fourier transform spread OFDM (DFT-S-OFDM) ) .
  • MCM multi-carrier modulation
  • OFDM orthogonal frequency division multiplexing
  • DFT-S-OFDM discrete Fourier transform spread OFDM
  • a resource element may consist of one symbol period (e.g., a duration of one modulation symbol) and one subcarrier, where the symbol period and subcarrier spacing are inversely related.
  • the number of bits carried by each resource element may depend on the modulation scheme (e.g., the order of the modulation scheme, the coding rate of the modulation scheme, or both) .
  • a wireless communications resource may refer to a combination of a radio frequency spectrum resource, a time resource, and a spatial resource (e.g., spatial layers or beams) , and the use of multiple spatial layers may further increase the data rate or data integrity for communications with a UE 115.
  • One or more numerologies for a carrier may be supported, where a numerology may include a subcarrier spacing ( ⁇ f) and a cyclic prefix.
  • a carrier may be divided into one or more BWPs having the same or different numerologies.
  • a UE 115 may be configured with multiple BWPs.
  • a single BWP for a carrier may be active at a given time and communications for the UE 115 may be restricted to one or more active BWPs.
  • Time intervals of a communications resource may be organized according to radio frames each having a specified duration (e.g., 10 milliseconds (ms) ) .
  • Each radio frame may be identified by a system frame number (SFN) (e.g., ranging from 0 to 1023) .
  • SFN system frame number
  • Each frame may include multiple consecutively numbered subframes or slots, and each subframe or slot may have the same duration.
  • a frame may be divided (e.g., in the time domain) into subframes, and each subframe may be further divided into a number of slots.
  • each frame may include a variable number of slots, and the number of slots may depend on subcarrier spacing.
  • Each slot may include a number of symbol periods (e.g., depending on the length of the cyclic prefix prepended to each symbol period) .
  • a slot may further be divided into multiple mini-slots containing one or more symbols. Excluding the cyclic prefix, each symbol period may contain one or more (e.g., N f ) sampling periods.
  • the duration of a symbol period may depend on the subcarrier spacing or frequency band of operation.
  • a subframe, a slot, a mini-slot, or a symbol may be the smallest scheduling unit (e.g., in the time domain) of the wireless communications system 100 and may be referred to as a transmission time interval (TTI) .
  • TTI duration e.g., the number of symbol periods in a TTI
  • the smallest scheduling unit of the wireless communications system 100 may be dynamically selected (e.g., in bursts of shortened TTIs (sTTIs) ) .
  • Physical channels may be multiplexed on a carrier according to various techniques.
  • a physical control channel and a physical data channel may be multiplexed on a downlink carrier, for example, using one or more of time division multiplexing (TDM) techniques, frequency division multiplexing (FDM) techniques, or hybrid TDM-FDM techniques.
  • a control region e.g., a control resource set (CORESET)
  • CORESET control resource set
  • a control region for a physical control channel may be defined by a number of symbol periods and may extend across the system bandwidth or a subset of the system bandwidth of the carrier.
  • One or more control regions (e.g., CORESETs) may be configured for a set of the UEs 115.
  • one or more of the UEs 115 may monitor or search control regions for control information according to one or more search space sets, and each search space set may include one or multiple control channel candidates in one or more aggregation levels arranged in a cascaded manner.
  • An aggregation level for a control channel candidate may refer to a number of control channel resources (e.g., control channel elements (CCEs) ) associated with encoded information for a control information format having a given payload size.
  • Search space sets may include common search space sets configured for sending control information to multiple UEs 115 and UE-specific search space sets for sending control information to a specific UE 115.
  • Each base station 105 may provide communication coverage via one or more cells, for example a macro cell, a small cell, a hot spot, or other types of cells, or any combination thereof.
  • the term “cell” may refer to a logical communication entity used for communication with a base station 105 (e.g., over a carrier) and may be associated with an identifier for distinguishing neighboring cells (e.g., a physical cell identifier (PCID) , a virtual cell identifier (VCID) , or others) .
  • a cell may also refer to a geographic coverage area 110 or a portion of a geographic coverage area 110 (e.g., a sector) over which the logical communication entity operates.
  • Such cells may range from smaller areas (e.g., a structure, a subset of structure) to larger areas depending on various factors such as the capabilities of the base station 105.
  • a cell may be or include a building, a subset of a building, or exterior spaces between or overlapping with geographic coverage areas 110, among other examples.
  • a macro cell generally covers a relatively large geographic area (e.g., several kilometers in radius) and may allow unrestricted access by the UEs 115 with service subscriptions with the network provider supporting the macro cell.
  • a small cell may be associated with a lower-powered base station 105, as compared with a macro cell, and a small cell may operate in the same or different (e.g., licensed, unlicensed) frequency bands as macro cells.
  • Small cells may provide unrestricted access to the UEs 115 with service subscriptions with the network provider or may provide restricted access to the UEs 115 having an association with the small cell (e.g., the UEs 115 in a closed subscriber group (CSG) , the UEs 115 associated with users in a home or office) .
  • a base station 105 may support one or multiple cells and may also support communications over the one or more cells using one or multiple component carriers.
  • the wireless communications system 100 may be a packet-based network that operates according to a layered protocol stack.
  • communications at the bearer or Packet Data Convergence Protocol (PDCP) layer may be IP-based.
  • a Radio Link Control (RLC) layer may perform packet segmentation and reassembly to communicate over logical channels.
  • RLC Radio Link Control
  • a Medium Access Control (MAC) layer may perform priority handling and multiplexing of logical channels into transport channels.
  • the MAC layer may also use error detection techniques, error correction techniques, or both to support retransmissions at the MAC layer to improve link efficiency.
  • the Radio Resource Control (RRC) protocol layer may provide establishment, configuration, and maintenance of an RRC connection between a UE 115 and a base station 105 or a core network 130 supporting radio bearers for user plane data.
  • RRC Radio Resource Control
  • transport channels may be mapped to physical channels.
  • a UE 115 While communicating with a base station 105, a UE 115 may experience an interruption in reception of packets.
  • a UE 115 may identify an interruption in reception of the packets based on identifying a missing packet according to a missing packet number.
  • the base station 105 may schedule retransmission of the packets. This scheduling and retransmission add additional latency and resource usage for the UE 115. If the UE 115 is a mobile device, extended power consumption can drain a battery life of the UE 115. This may also negatively impact an overall user experience.
  • a UE 115 may determine a link failure in response to a packet loss rather than await retransmission or other operations from the base station 105.
  • the UE 115 may determine that a packet loss occurred when there is a hop between two received packets from the base station 105 and the hop meets a threshold (e.g., a difference between the packet numbers of the two received packets) , without receiving an indication of the packet loss from the base station 105. This hop is an indication to the UE 115 that there is a missed packet from the base station 105.
  • the UE 115 can establish another radio link with a different base station 105 using a different RAT to mitigate the effects of the packet loss.
  • the UE 115 can receive the packets from the different base station 105 at a reduced latency cost compared to if the UE 115 was to wait for the current base station 105 to resolve the link failure.
  • other RAT e.g., from 5G to 4G or vice-versa
  • UEs 115 may receive multiple PDUs. Each PDU may include a PDCP sequence number. The UEs 115 may process the PDUs according to the PDCP sequence number. The UEs 115 may use the PDCP sequence number to deliver each PDU in a correct order to higher layers (e.g., an RRC layer, a PDCP layer, an RLC layer) of a protocol stack of the UEs 115. In some cases, the UEs 115 may experience a delay or an interruption in reception of the PDUs, and thereby may experience reduced reliability and increased latency for reception of data carried in the PDUs. As demand for communication efficiency increases, it may thus be desirable for the UEs 115 to improve detecting a delay or an interruption in reception of the PDUs to reduce a delay or an interruption in wireless communications (e.g., data stalls) as described herein.
  • wireless communications e.g., data stalls
  • the UEs 115 may be configured to support recovering from a delay or an interruption in reception of PDUs by determining that a PDCP sequence number hopping threshold has been satisfied. Because each PDU corresponds to a PDCP sequence number, the UEs 115 may improve efficiency for detecting a delay or an interruption in reception of the PDUs using the PDCP sequence number hopping threshold.
  • the UEs 115 may receive PDUs while camping on a first cell, and upon detecting a data stall event (e.g., based on a sequence number of a received PDU satisfying a PDCP sequence number hopping threshold) , the UEs 115 may switch from camping on the first cell to camping on a second cell to reduce latency and improve reliability for PDU reception at the UEs 115. As part of switching cells, the UEs 115 may trigger a data transfer operation, such that the UEs 115 may continue to receive data (i.e., PDUs) from a second cell and thereby reducing latency and improving user experience.
  • a data stall event e.g., based on a sequence number of a received PDU satisfying a PDCP sequence number hopping threshold
  • a base station 105 may be movable and therefore provide communication coverage for a moving geographic coverage area 110.
  • different geographic coverage areas 110 associated with different technologies may overlap, but the different geographic coverage areas 110 may be supported by the same base station 105.
  • the overlapping geographic coverage areas 110 associated with different technologies may be supported by different base stations 105.
  • the wireless communications system 100 may include, for example, a heterogeneous network in which different types of the base stations 105 provide coverage for various geographic coverage areas 110 using the same or different radio access technologies.
  • the wireless communications system 100 may support synchronous or asynchronous operation.
  • the base stations 105 may have similar frame timings, and transmissions from different base stations 105 may be approximately aligned in time.
  • the base stations 105 may have different frame timings, and transmissions from different base stations 105 may, in some examples, not be aligned in time.
  • the techniques described herein may be used for either synchronous or asynchronous operations.
  • Some UEs 115 may be low cost or low complexity devices and may provide for automated communication between machines (e.g., via Machine-to-Machine (M2M) communication) .
  • M2M communication or MTC may refer to data communication technologies that allow devices to communicate with one another or a base station 105 without human intervention.
  • M2M communication or MTC may include communications from devices that integrate sensors or meters to measure or capture information and relay such information to a central server or application program that makes use of the information or presents the information to humans interacting with the application program.
  • Some UEs 115 may be designed to collect information or enable automated behavior of machines or other devices. Examples of applications for MTC devices include smart metering, inventory monitoring, water level monitoring, equipment monitoring, healthcare monitoring, wildlife monitoring, weather and geological event monitoring, fleet management and tracking, remote security sensing, physical access control, and transaction-based business charging.
  • Some UEs 115 may be configured to employ operating modes that reduce power consumption, such as half-duplex communications (e.g., a mode that supports one-way communication via transmission or reception, but not transmission and reception simultaneously) .
  • half-duplex communications may be performed at a reduced peak rate.
  • Other power conservation techniques for the UEs 115 include entering a power saving deep sleep mode when not engaging in active communications, operating over a limited bandwidth (e.g., according to narrowband communications) , or a combination of these techniques.
  • some UEs 115 may be configured for operation using a narrowband protocol type that is associated with a defined portion or range (e.g., set of subcarriers or resource blocks (RBs) ) within a carrier, within a guard-band of a carrier, or outside of a carrier.
  • a narrowband protocol type that is associated with a defined portion or range (e.g., set of subcarriers or resource blocks (RBs) ) within a carrier, within a guard-band of a carrier, or outside of a carrier.
  • the wireless communications system 100 may be configured to support ultra-reliable communications or low-latency communications, or various combinations thereof.
  • the wireless communications system 100 may be configured to support ultra-reliable low-latency communications (URLLC) or mission critical communications.
  • the UEs 115 may be designed to support ultra-reliable, low-latency, or critical functions (e.g., mission critical functions) .
  • Ultra-reliable communications may include private communication or group communication and may be supported by one or more mission critical services such as mission critical push-to-talk (MCPTT) , mission critical video (MCVideo) , or mission critical data (MCData) .
  • MCPTT mission critical push-to-talk
  • MCVideo mission critical video
  • MCData mission critical data
  • Support for mission critical functions may include prioritization of services, and mission critical services may be used for public safety or general commercial applications.
  • the terms ultra-reliable, low-latency, mission critical, and ultra-reliable low-latency may be used interchangeably herein.
  • a UE 115 may also be able to communicate directly with other UEs 115 over a device-to-device (D2D) communication link 135 (e.g., using a peer-to-peer (P2P) or D2D protocol) .
  • D2D device-to-device
  • P2P peer-to-peer
  • One or more UEs 115 utilizing D2D communications may be within the geographic coverage area 110 of a base station 105.
  • Other UEs 115 in such a group may be outside the geographic coverage area 110 of a base station 105 or be otherwise unable to receive transmissions from a base station 105.
  • groups of the UEs 115 communicating via D2D communications may utilize a one-to-many (1: M) system in which each UE 115 transmits to every other UE 115 in the group.
  • a base station 105 facilitates the scheduling of resources for D2D communications. In other cases, D2D communications are carried out between the UEs 115 without the involvement of a base station 105.
  • the core network 130 may provide user authentication, access authorization, tracking, Internet Protocol (IP) connectivity, and other access, routing, or mobility functions.
  • the core network 130 may be an evolved packet core (EPC) or 5G core (5GC) , which may include at least one control plane entity that manages access and mobility (e.g., a mobility management entity (MME) , an access and mobility management function (AMF) ) and at least one user plane entity that routes packets or interconnects to external networks (e.g., a serving gateway (S-GW) , a Packet Data Network (PDN) gateway (P-GW) , or a user plane function (UPF) ) .
  • EPC evolved packet core
  • 5GC 5G core
  • MME mobility management entity
  • AMF access and mobility management function
  • S-GW serving gateway
  • PDN Packet Data Network gateway
  • UPF user plane function
  • the control plane entity may manage non-access stratum (NAS) functions such as mobility, authentication, and bearer management for the UEs 115 served by the base stations 105 associated with the core network 130.
  • NAS non-access stratum
  • User IP packets may be transferred through the user plane entity, which may provide IP address allocation as well as other functions.
  • the user plane entity may be connected to the network operators IP services 150.
  • the operators IP services 150 may include access to the Internet, Intranet (s) , an IP Multimedia Subsystem (IMS) , or a Packet-Switched Streaming Service.
  • Some of the network devices may include subcomponents such as an access network entity 140, which may be an example of an access node controller (ANC) .
  • Each access network entity 140 may communicate with the UEs 115 through one or more other access network transmission entities 145, which may be referred to as radio heads, smart radio heads, or transmission/reception points (TRPs) .
  • Each access network transmission entity 145 may include one or more antenna panels.
  • various functions of each access network entity 140 or base station 105 may be distributed across various network devices (e.g., radio heads and ANCs) or consolidated into a single network device (e.g., a base station 105) .
  • the wireless communications system 100 may operate using one or more frequency bands, typically in the range of 300 megahertz (MHz) to 300 gigahertz (GHz) .
  • the region from 300 MHz to 3 GHz is known as the ultra-high frequency (UHF) region or decimeter band because the wavelengths range from approximately one decimeter to one meter in length.
  • UHF waves may be blocked or redirected by buildings and environmental features, but the waves may penetrate structures sufficiently for a macro cell to provide service to the UEs 115 located indoors.
  • the transmission of UHF waves may be associated with smaller antennas and shorter ranges (e.g., less than 100 kilometers) compared to transmission using the smaller frequencies and longer waves of the high frequency (HF) or very high frequency (VHF) portion of the spectrum below 300 MHz.
  • HF high frequency
  • VHF very high frequency
  • the wireless communications system 100 may also operate in a super high frequency (SHF) region using frequency bands from 3 GHz to 30 GHz, also known as the centimeter band, or in an extremely high frequency (EHF) region of the spectrum (e.g., from 30 GHz to 300 GHz) , also known as the millimeter band.
  • SHF super high frequency
  • EHF extremely high frequency
  • the wireless communications system 100 may support millimeter wave (mmW) communications between the UEs 115 and the base stations 105, and EHF antennas of the respective devices may be smaller and more closely spaced than UHF antennas. In some examples, this may facilitate use of antenna arrays within a device.
  • mmW millimeter wave
  • the propagation of EHF transmissions may be subject to even greater atmospheric attenuation and shorter range than SHF or UHF transmissions.
  • the techniques disclosed herein may be employed across transmissions that use one or more different frequency regions, and designated use of bands across these frequency regions may differ by country or regulating body.
  • the wireless communications system 100 may utilize both licensed and unlicensed radio frequency spectrum bands.
  • the wireless communications system 100 may employ License Assisted Access (LAA) , LTE-Unlicensed (LTE-U) RAT, or NR technology in an unlicensed band such as the 5 GHz industrial, scientific, and medical (ISM) band.
  • LAA License Assisted Access
  • LTE-U LTE-Unlicensed
  • NR NR technology
  • an unlicensed band such as the 5 GHz industrial, scientific, and medical (ISM) band.
  • devices such as the base stations 105 and the UEs 115 may employ carrier sensing for collision detection and avoidance.
  • operations in unlicensed bands may be based on a carrier aggregation configuration in conjunction with component carriers operating in a licensed band (e.g., LAA) .
  • Operations in unlicensed spectrum may include downlink transmissions, uplink transmissions, P2P transmissions, or D2D transmissions, among other examples.
  • a base station 105 or a UE 115 may be equipped with multiple antennas, which may be used to employ techniques such as transmit diversity, receive diversity, multiple-input multiple-output (MIMO) communications, or beamforming.
  • the antennas of a base station 105 or a UE 115 may be located within one or more antenna arrays or antenna panels, which may support MIMO operations or transmit or receive beamforming.
  • one or more base station antennas or antenna arrays may be co-located at an antenna assembly, such as an antenna tower.
  • antennas or antenna arrays associated with a base station 105 may be located in diverse geographic locations.
  • a base station 105 may have an antenna array with a number of rows and columns of antenna ports that the base station 105 may use to support beamforming of communications with a UE 115.
  • a UE 115 may have one or more antenna arrays that may support various MIMO or beamforming operations.
  • an antenna panel may support radio frequency beamforming for a signal transmitted via an antenna port.
  • the base stations 105 or the UEs 115 may use MIMO communications to exploit multipath signal propagation and increase the spectral efficiency by transmitting or receiving multiple signals via different spatial layers. Such techniques may be referred to as spatial multiplexing.
  • the multiple signals may, for example, be transmitted by the transmitting device via different antennas or different combinations of antennas. Likewise, the multiple signals may be received by the receiving device via different antennas or different combinations of antennas.
  • Each of the multiple signals may be referred to as a separate spatial stream and may carry bits associated with the same data stream (e.g., the same codeword) or different data streams (e.g., different codewords) .
  • Different spatial layers may be associated with different antenna ports used for channel measurement and reporting.
  • MIMO techniques include single-user MIMO (SU-MIMO) , where multiple spatial layers are transmitted to the same receiving device, and multiple-user MIMO (MU-MIMO) , where multiple spatial layers are transmitted to multiple devices.
  • SU-MIMO single-user MIMO
  • Beamforming which may also be referred to as spatial filtering, directional transmission, or directional reception, is a signal processing technique that may be used at a transmitting device or a receiving device (e.g., a base station 105, a UE 115) to shape or steer an antenna beam (e.g., a transmit beam, a receive beam) along a spatial path between the transmitting device and the receiving device.
  • Beamforming may be achieved by combining the signals communicated via antenna elements of an antenna array such that some signals propagating at particular orientations with respect to an antenna array experience constructive interference while others experience destructive interference.
  • the adjustment of signals communicated via the antenna elements may include a transmitting device or a receiving device applying amplitude offsets, phase offsets, or both to signals carried via the antenna elements associated with the device.
  • the adjustments associated with each of the antenna elements may be defined by a beamforming weight set associated with a particular orientation (e.g., with respect to the antenna array of the transmitting device or receiving device, or with respect to some other orientation) .
  • a base station 105 or a UE 115 may use beam sweeping techniques as part of beam forming operations.
  • a base station 105 may use multiple antennas or antenna arrays (e.g., antenna panels) to conduct beamforming operations for directional communications with a UE 115.
  • Some signals e.g., synchronization signals, reference signals, beam selection signals, or other control signals
  • the base station 105 may transmit a signal according to different beamforming weight sets associated with different directions of transmission.
  • Transmissions in different beam directions may be used to identify (e.g., by a transmitting device, such as a base station 105, or by a receiving device, such as a UE 115) a beam direction for later transmission or reception by the base station 105.
  • a transmitting device such as a base station 105
  • a receiving device such as a UE 115
  • transmissions by a device may be performed using multiple beam directions, and the device may use a combination of digital precoding or radio frequency beamforming to generate a combined beam for transmission (e.g., from a base station 105 to a UE 115) .
  • the UE 115 may report feedback that indicates precoding weights for one or more beam directions, and the feedback may correspond to a configured number of beams across a system bandwidth or one or more sub-bands.
  • the base station 105 may transmit a reference signal (e.g., a cell-specific reference signal (CRS) , a channel state information reference signal (CSI-RS) ) , which may be precoded or unprecoded.
  • a reference signal e.g., a cell-specific reference signal (CRS) , a channel state information reference signal (CSI-RS)
  • CRS cell-specific reference signal
  • CSI-RS channel state information reference signal
  • the UE 115 may provide feedback for beam selection, which may be a precoding matrix indicator (PMI) or codebook-based feedback (e.g., a multi-panel type codebook, a linear combination type codebook, a port selection type codebook) .
  • PMI precoding matrix indicator
  • codebook-based feedback e.g., a multi-panel type codebook, a linear combination type codebook, a port selection type codebook
  • a UE 115 may employ similar techniques for transmitting signals multiple times in different directions (e.g., for identifying a beam direction for subsequent transmission or reception by the UE 115) or for transmitting a signal in a single direction (e.g., for transmitting data to a receiving device) .
  • a receiving device may try multiple receive configurations (e.g., directional listening) when receiving various signals from the base station 105, such as synchronization signals, reference signals, beam selection signals, or other control signals.
  • receive configurations e.g., directional listening
  • a receiving device may try multiple receive directions by receiving via different antenna subarrays, by processing received signals according to different antenna subarrays, by receiving according to different receive beamforming weight sets (e.g., different directional listening weight sets) applied to signals received at multiple antenna elements of an antenna array, or by processing received signals according to different receive beamforming weight sets applied to signals received at multiple antenna elements of an antenna array, any of which may be referred to as “listening” according to different receive configurations or receive directions.
  • receive beamforming weight sets e.g., different directional listening weight sets
  • a receiving device may use a single receive configuration to receive along a single beam direction (e.g., when receiving a data signal) .
  • the single receive configuration may be aligned in a beam direction determined based on listening according to different receive configuration directions (e.g., a beam direction determined to have a highest signal strength, highest signal-to-noise ratio (SNR) , or otherwise acceptable signal quality based on listening according to multiple beam directions) .
  • SNR signal-to-noise ratio
  • the UEs 115 and the base stations 105 may support retransmissions of data to increase the likelihood that data is received successfully.
  • Hybrid automatic repeat request (HARQ) feedback is one technique for increasing the likelihood that data is received correctly over a communication link 125.
  • HARQ may include a combination of error detection (e.g., using a cyclic redundancy check (CRC) ) , forward error correction (FEC) , and retransmission (e.g., automatic repeat request (ARQ) ) .
  • FEC forward error correction
  • ARQ automatic repeat request
  • HARQ may improve throughput at the MAC layer in poor radio conditions (e.g., low signal-to-noise conditions) .
  • a device may support same-slot HARQ feedback, where the device may provide HARQ feedback in a specific slot for data received in a previous symbol in the slot. In other cases, the device may provide HARQ feedback in a subsequent slot, or according to some other time interval.
  • FIG. 2 illustrates an example of a wireless communications system 200 that supports recovering from a data stall in wireless communications systems in accordance with aspects of the present disclosure.
  • the wireless communications system 200 may implement aspects of the wireless communications system 100.
  • the wireless communications system 200 may include a base station 105-a and a base station 105-b, as well as a UE 115-a, which may be examples of a base station 105 and a UE 115 as described herein.
  • the wireless communications system 200 may support multiple radio access technologies including 4G systems such as LTE systems, LTE-A systems, or LTE-A Pro systems, and 5G systems, which may be referred to as NR systems.
  • 4G systems such as LTE systems, LTE-A systems, or LTE-A Pro systems
  • 5G systems which may be referred to as NR systems.
  • the wireless communications system 200 may be a packet-based network that operates according to a layered protocol stack.
  • wireless communications at a PDCP layer may be IP-based.
  • An RLC layer may perform packet segmentation and reassembly to communicate over logical channels.
  • a MAC layer may perform priority handling and multiplexing of logical channels into transport channels.
  • the MAC layer may also use error detection techniques, error correction techniques, or both to support retransmissions at the MAC layer to improve link efficiency.
  • an RRC protocol layer may provide establishment, configuration, and maintenance of an RRC connection between the UE 115-a and the base stations 105-a or the base station 105-b.
  • the base station 105-a, the base station 105-b, and the UE 115-a may be configured with multiple antennas, which may be used to employ techniques such as transmit diversity, receive diversity, multiple-input multiple-output communications, or beamforming, or any combination thereof.
  • the antennas of the base station 105-a, the base station 105-b, and the UE 115-a may be located within one or more antenna arrays or antenna panels, which may support multiple-input multiple-output operations or transmit or receive beamforming.
  • An antenna panel may support radio frequency beamforming for a signal transmitted via one or more antenna ports.
  • the base station 105-a, the base station 105-b, and the UE 115-a may thereby be configured to support wireless communications (e.g., beamformed communications) using the multiple antennas.
  • Each base station 105 may provide communication coverage via one or more cells, for example a macro cell, a small cell, a hot spot, or other types of cells, or any combination thereof.
  • the base stations 105 may support various radio access technologies, such as 4G LTE and 5G NR.
  • the base station 105-a may support 5G NR
  • the base station 105-b may support 4G LTE.
  • the UE 115-a may also be capable of supporting wireless communications over various radio access technologies, such as 4G LTE and 5G NR.
  • the UE 115-a may, in some examples, support wireless communication according to an operating mode, such as a non-standalone mode or a standalone mode.
  • the UE 115-a may, in some examples, perform a cell selection procedure and a re-selection procedure according to the operating mode.
  • a UE 115 may select a cell associated with a base station 105 to camp on. After camping on the cell, the UE 115 may monitor system information, perform measurements on the cell and neighboring cells based on measurement rules, and select a different cell to camp on based on a cell re-selection criterion. The UE 115 may perform cell selection or re-selection using selection or re-selection-related parameters from the system information or from an RRC message received from the base station 105. In the example of FIG. 2, the UE 115-a may select a cell associated with the base station 105-a to camp on. In other words, the UE 115-a may camp on a 5G NR cell. In some cases, the UE 115-a may switch from camping on the cell associated with the base station 105-a to camping on a cell associated with the base station 105-b.
  • the UE 115-a may, for example, receive one or multiple PDUs 205 carrying data 210 from the base station 105-a.
  • Each PDU 205 may include a PDCP sequence number.
  • the UE 115-a may process the PDUs 205 according to the PDCP sequence number.
  • the UE 115-a may use the PDCP sequence number to deliver each PDU 205 in a correct order to one or more higher layers of a protocol stack.
  • the UE 115-a may, in some cases, experience a delay or an interruption in reception of the PDUs 205 from the base station 105-a, and thereby may experience reduced reliability and increased latency for reception of the data 210 carried in the PDUs205.
  • the UE 115-a may be configured to support recovering from a delay or an interruption in reception of PDUs 205 by determining that a PDCP sequence number hopping threshold has been satisfied. Because each PDU 205 corresponds to a PDCP sequence number, the UE 115-a may improve efficiency for detecting a delay or an interruption in reception of the PDUs 205 using the PDCP sequence number hopping threshold.
  • the UE 115-a may receive PDUs 205 carrying the data 210 while camping on the cell associated with the base station 105-a, and upon detecting a data stall event based on a sequence number of a received PDU 205 satisfying a PDCP sequence number hopping threshold, the UE 115-a may switch cells.
  • the UE 115-a may switch from camping on the cell associated with the base station 105-a to camping on a cell associated with the base station 105-b.
  • the UE 115-a may determine a difference between a PDCP sequence number associated with a received PDU 205 and a previous PDCP sequence number associated with a previous PDU205, and determine that the difference satisfies the PDCP sequence number hopping threshold.
  • the base station 105-a may send a PDU 205 having a PDCP sequence number s n followed by another PDU 205 having a PDCP sequence number s n +m, where m is an integer value.
  • the difference may be based on a PDCP sequence number in a current slot minus a PDCP sequence number in a latest pervious slot being greater than the PDCP sequence number hopping threshold.
  • the received PDU and the previous received PDU 205 may be contiguous in a time domain. In some other examples, the received PDU 205 and the previous received PDU 205 may be noncontiguous in a time domain.
  • the UE 115-a may reduce latency and improve reliability for PDU 205 reception at the UE 115-a.
  • the UE 115-a may select the cell associated with the base station 105-b, for example, based on performing a cell selection procedure or a re-selection procedure.
  • the UE 115-a may switch from camping on the cell associated with the base station 105-a to camping on a cell associated with the base station 105-b while operating in a non-standalone mode or a standalone mode.
  • the UE 115-a may fallback to the base station 105-b while operating either in the non-standalone mode or the standalone mode by attaching to the base station 105-b (e.g., an LTE cell) based at least in part on a tracking area procedure.
  • the UE 115-a may also trigger a data transfer operation, such that the UEs 115 may continue to receive data (i.e., PDUs 205) from the base station 105-b and thereby reducing latency and improving user experience as described herein.
  • data i.e., PDUs 205
  • FIG. 3 illustrates an example of a process flow 300 that supports recovering from a data stall in wireless communications systems in accordance with aspects of the present disclosure.
  • the process flow 300 may implement aspects of the wireless communications system 100 and 200 described with reference to FIGs. 1 and 2, respectively.
  • the process flow 300 may be based on a configuration by a base station 105-c or a base station 105-d, or both, or a UE 115-b, and implemented by the UE 115-b and may promote high reliability and low latency wireless communications by recovering from a delay or an interruption in wireless communications when camping on a cell in a wireless communications system.
  • the process flow 300 may also be based on a configuration by the base station 105-c or the base station 105-d, or both, or the UE 115-b, and implemented by the UE 115-b to reduce power consumption for the UE 115-b, among other benefits.
  • the base stations 105-c, 105-d and the UE 115-b may be examples of a base station 105 and a UE 115, as described with reference to FIGs. 1 and 2.
  • the operations between the base stations 105-c, 105-d and the UE 115-b may be transmitted in a different order than the example order shown, or the operations performed by the base stations 105-c, 105-d and the UE 115-b may be performed in different orders or at different times. Some operations may also be omitted from the process flow 300, and other operations may be added to the process flow 300.
  • the UE 115-b may be operating in a standalone mode or a non-standalone mode in a wireless communications system, such as the wireless communications system 100 and 200 described with reference to FIGs. 1 and 2.
  • the base station 105-b and the base station 105-c may provide communication coverage, in the wireless communications system, via one or more cells.
  • the base station 105-c may provide a cell supporting 5G NR, while the base station 105-d may provide a cell supporting 4G LTE.
  • the UE 115-b may perform cell selection and re-selection when operating in a standalone mode or a non-standalone mode to decrease a delay or mitigate an interruption in wireless communications when camping on a cell associated with the base station 105-c or the base station 105-d.
  • a UE 115-b and a base station 105-c may, for example, perform a packet-switched data transfer.
  • the UE 115-b and the base station 105-c may transmit and receive wireless communications to and from one another in the form of PDUs (or PDCP PDUs) .
  • the UE 115-b and the base station 105-c may transmit and receive PDUs over an unlicensed spectrum, which may be a portion of spectrum that includes frequency bands traditionally used by Wi-Fi technology, such as the 2.4 GHz band, the 5 GHz band, the 60 GHz band, the 3.6 GHz band, and the 900 MHz band.
  • the UE 115-b and the base station 105-c may communicate in other frequency bands, such as the 6 GHz band, which may support both licensed and unlicensed communications.
  • the UE 115-b and the base station 105-c may also be configured to communicate over other frequency bands such as shared licensed frequency bands, where multiple operators may have a license to operate in the same or overlapping frequency band or bands.
  • the base station 105-c may transmit one or multiple PDUs to the UE 115-b.
  • the UE 115-b may detect PDCP sequence number hopping. For example, the UE 115-b may determine a difference between a PDCP sequence number associated with a received PDU and a previous PDCP sequence number associated with a previous PDU, and determine that the difference satisfies the PDCP sequence number hopping threshold.
  • the received PDU and the previous received PDU may be contiguous in a time domain or noncontiguous in the time domain.
  • the UE 115-b may switch cells based on the detected PDCP sequence number hopping.
  • the UE 115-b may switch from camping on a cell associated with the base station 105-c to camping on a cell associated with the base station 105-d while operating in a non-standalone mode or a standalone mode.
  • the UE 115-b may fallback to the base station 105-d while operating either in the non-standalone mode or the standalone mode.
  • the UE 115-b may operate in a non-standalone mode.
  • the UE 115-b may switch an operating mode, for example, the UE 115-b may switch to a non-standalone mode.
  • the UE 115-b may transmit a TAU update request message to the base station 105-d.
  • the UE 115-b may transmit the TAU update request message to the base station 105-d based at least in part on the cell selection procedure or a cell re-selection procedure.
  • the TAU update request message may be a request by the UE 115-b to connect to the base station 105-d (e.g., an LTE cell) .
  • the TAU update request message may include dual-connectivity capability information, which may indicate that the UE 115-b supports dual-connectivity. That is, the base station 105-c (e.g., an NR cell) acts as a primary cell or node and the base station 105-d (e.g., an LTE cell) acts as a secondary cell or node for the UE 115-b.
  • dual-connectivity capability information may indicate that the UE 115-b supports dual-connectivity. That is, the base station 105-c (e.g., an NR cell) acts as a primary cell or node and the base station 105-d (e.g., an LTE cell) acts as a secondary cell or node for the UE 115-b.
  • the base station 105-d may transmit a TAU update response message to the UE 115-b in response to the TAU update request message.
  • the TAU update response message may acknowledge (e.g., accept) the TAU update request message from the UE 115-b.
  • the UE 115-b may inform the base station 105-d (e.g., the 4G LTE cell) about a geolocation of the UE 115-b in order to facilitate network services to the UE 115-b, as well as to facilitate connecting to the base station 105-d (e.g., the 4G LTE cell) .
  • the UE 115-b may perform a tracking area procedure before camping on the new cell (i.e., the 4G LTE cell) , which may be in a different tracking area.
  • the UE 115-b may thereby support a TAU procedure to camp on a cell associated with the base station 105-d.
  • the UE 115-b may perform the TAU procedure when the UE 115-b transverses a tracking area boundary by transmitting to the base station 105-d (e.g., the 4G LTE cell) a TAU update request message along with RRC parameters indicating a selected network.
  • the base station 105-d may forward the TAU update request message to a corresponding mobility management entity (MME) to facilitate the cell switching for the UE 115-b.
  • MME mobility management entity
  • the TAU update request message may include a cell subscriber group (CSG) identifier, which identifies subscribers of an operator who are permitted to access one or more cells, access mode, a tracking area identifier (TAI) of the cell from where it received the TAU update request message and with the selected network.
  • CSG cell subscriber group
  • TAI tracking area identifier
  • the UE 115-d may transmit a service request message to the base station 105-d.
  • the UE 115-b may also trigger a packet-switched data transfer operation, such that the UE 115-b may continue to receive data (i.e., PDUs) from the base station 105-d and thereby reducing latency and improving user experience as described herein.
  • the UE 115-b and the base station 105-d may, for example, perform a packet-switched data transfer.
  • FIG. 4 illustrates an example of a process flow 400 that supports recovering from a data stall in wireless communications systems in accordance with aspects of the present disclosure.
  • the process flow 400 may implement aspects of the wireless communications system 100 and 200 described with reference to FIGs. 1 and 2, respectively.
  • the process flow 400 may be based on a configuration by a base station 105-e or a base station 105-f, or both, or a UE 115-c, and implemented by the UE 115-c and may promote high reliability and low latency wireless communications by recovering from a delay or an interruption in wireless communications when camping on a cell in a wireless communications system.
  • the process flow 400 may also be based on a configuration by the base station 105-e or the base station 105-f, or both, or the UE 115-c, and implemented by the UE 115-c to decrease power consumption for the UE 115-c, among other benefits.
  • the base stations 105-e, 105-f and the UE 115-c may be examples of a base station 105 and a UE 115, as described with reference to FIGs. 1 and 2.
  • the operations between the base stations 105-e, 105-f and the UE 115-c may be transmitted in a different order than the example order shown, or the operations performed by the base stations 105-e, 105-f and the UE 115-c may be performed in different orders or at different times. Some operations may also be omitted from the process flow 400, and other operations may be added to the process flow 400.
  • the UE 115-c may be operating in a standalone mode or a non-standalone mode in a wireless communications system, such as the wireless communications system 100 and 200 described with reference to FIGs. 1 and 2.
  • the base station 105-e and the base station 105-f may provide communication coverage, in the wireless communications system, via one or more cells.
  • the base station 105-e may provide a cell supporting 5G NR, while the base station 105-f may provide a cell supporting 4G LTE.
  • the UE 115-c may perform cell selection and re-selection when operating in a standalone mode or a non-standalone mode to decrease a delay or mitigate an interruption in wireless communications when camping on a cell associated with the base station 105-e or the base station 105-f.
  • a UE 115-c and a base station 105-e may, for example, perform a packet-switched data transfer. As part of the packet-switch data transfer, the UE 115-c and the base station 105-e may transmit and receive wireless communications to and from one another in the form of PDUs (or PDCP PDUs) as described herein.
  • the base station 105-e may transmit one or multiple PDUs to the UE 115-c.
  • the UE 115-c may detect PDCP sequence number hopping. For example, the UE 115-c may determine a difference between two or more PDCP sequence numbers associated with two or more received PDUs.
  • the UE 115-c may determine a difference between a first PDCP sequence number associated with a first received PDU and a second PDCP sequence number associated with a second PDU, and determine that the difference satisfies the PDCP sequence number hopping threshold.
  • the first PDU and the second PDU may be contiguous in a time domain or noncontiguous in the time domain.
  • the UE 115-c may switch cells based on the detected PDCP sequence number hopping. For example, the UE 115-c may switch from camping on a cell associated with the base station 105-e to camping on a cell associated with the base station 105-f while operating in a non-standalone mode or a standalone mode. For example, the UE 115-c may fallback to the base station 105-f while operating either in the non-standalone mode or the standalone mode. In the example of FIG.
  • the UE 115-c may operate in a standalone mode, and thereby may switch from camping on a cell associated with the base station 105-e (e.g., an NR cell) to camping on a cell associated with the base station 105-f (e.g., an LTE cell) .
  • the UE 115-c may modify a value of the PDCP sequence number hopping threshold based on camping on the cell associated with the base station 105-f (e.g., an LTE cell) .
  • the UE 115-c may increase (e.g., increment) the value of the PDCP sequence number hopping threshold based at least in part on a defined value.
  • the UE 115-c may transmit a TAU request message to the base station 105-f.
  • the UE 115-c may transmit the TAU request message to the base station 105-f based at least in part on the cell selection procedure or a cell re-selection procedure.
  • the TAU request message may be a request by the UE 115-c to connect to the base station 105-f (e.g., an LTE cell) .
  • the TAU request message may include dual-connectivity NR capability information, which may indicate that the UE 115-c does not support dual-connectivity. In the example of FIG. 4, the UE 115-c might not support dual-connectivity, and thereby may operate in a standalone mode.
  • the base station 105-f may transmit a TAU response message to the UE 115-c in response to the TAU request message.
  • the TAU response message may acknowledge (e.g., accept) the TAU request message from the UE 115-c.
  • the TAU response message may be a TAU accept.
  • the UE 115-c may inform the base station 105-f (e.g., the 4G LTE cell) about a geolocation of the UE 115-c in order to facilitate network services to the UE 115-c, as well as to facilitate connecting to the base station 105-f (e.g., the 4G LTE cell) .
  • the UE 115-c may perform a tracking area procedure before camping on the new cell (i.e., the 4G LTE cell) , which may be in a different tracking area.
  • the UE 115-c may transmit a service request message to the base station 105-f.
  • the UE 115-c may also trigger a packet-switched data transfer operation, such that the UE 115-c may continue to receive data (i.e., PDUs) from the base station 105-f and thereby reducing latency and improving user experience as described herein.
  • the UE 115-c and the base station 105-f may, for example, perform a packet-switched data transfer.
  • FIG. 5 shows a diagram 500 of a device 505 that supports recovering from a data stall in wireless communications systems in accordance with aspects of the present disclosure.
  • the device 505 may be an example of aspects of a UE 115 as described herein.
  • the device 505 may include a receiver 510, a UE communications manager 515, and a transmitter 520.
  • the device 505 may also include a processor. Each of these components may be in communication with one another (e.g., via one or more buses) .
  • the receiver 510 may receive information such as packets, user data, or control information associated with various information channels (e.g., control channels, data channels, and information related to recovering from a data stall in wireless communications systems, etc. ) . Information may be passed on to other components of the device 505.
  • the receiver 510 may be an example of aspects of the transceiver 820 described with reference to FIG. 8.
  • the receiver 510 may utilize a single antenna or a set of antennas.
  • the UE communications manager 515 may receive a packet associated with a PDCP sequence number, determine that the PDCP sequence number satisfies a PDCP sequence number hopping threshold, determine a radio link failure condition based on the PDCP sequence number satisfying the PDCP sequence number hopping threshold, and switch from operating in a first RAT to operating in a second RAT based on the radio link failure condition.
  • the UE communications manager 515 may be an example of aspects of the UE communications manager 810 described herein.
  • the UE communications manager 515 may be implemented as an integrated circuit or chipset for a mobile device modem, and the receiver 510 and the transmitter 520 may be implemented as analog components (e.g., amplifiers, filters, antennas, etc. ) coupled with the mobile device modem to enable wireless transmission and reception.
  • the UE communications manager 515 as described herein may be implemented to realize one or more potential improvements. At least one implementation may enable the UE communications manager 515 to determine that a PDCP sequence number associated with a received PDU satisfies a PDCP sequence number hopping threshold.
  • one or more processors of the device 505 may experience reduce power consumption and promote high reliability and low latency wireless communications, among other benefits
  • the UE communications manager 515 may be implemented in hardware, code (e.g., software or firmware) executed by a processor, or any combination thereof. If implemented in code executed by a processor, the functions of the UE communications manager 515, or its sub-components may be executed by a general-purpose processor, a DSP, an application-specific integrated circuit (ASIC) , a FPGA or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described in the present disclosure.
  • code e.g., software or firmware
  • ASIC application-specific integrated circuit
  • FPGA field-programmable gate
  • the UE communications manager 515 may be physically located at various positions, including being distributed such that portions of functions are implemented at different physical locations by one or more physical components.
  • the UE communications manager 515, or its sub-components may be a separate and distinct component in accordance with various aspects of the present disclosure.
  • the UE communications manager 515, or its sub-components may be combined with one or more other hardware components, including but not limited to an input/output (I/O) component, a transceiver, a network server, another computing device, one or more other components described in the present disclosure, or a combination thereof in accordance with various aspects of the present disclosure.
  • I/O input/output
  • the transmitter 520 may transmit signals generated by other components of the device 505.
  • the transmitter 520 may be collocated with a receiver 510 in a transceiver module.
  • the transmitter 520 may be an example of aspects of the transceiver 820 described with reference to FIG. 8.
  • the transmitter 520 may utilize a single antenna or a set of antennas.
  • FIG. 6 shows a diagram 600 of a device 605 that supports recovering from a data stall in wireless communications systems in accordance with aspects of the present disclosure.
  • the device 605 may be an example of aspects of a device 505, or a UE 115 as described herein.
  • the device 605 may include a receiver 610, a UE communications manager 615, and a transmitter 640.
  • the device 605 may also include a processor. Each of these components may be in communication with one another (e.g., via one or more buses) .
  • the receiver 610 may receive information such as packets, user data, or control information associated with various information channels (e.g., control channels, data channels, and information related to recovering from a data stall in wireless communications systems, etc. ) . Information may be passed on to other components of the device 605.
  • the receiver 610 may be an example of aspects of the transceiver 820 described with reference to FIG. 8.
  • the receiver 610 may utilize a single antenna or a set of antennas.
  • the UE communications manager 615 may be an example of aspects of the UE communications manager 515 as described herein.
  • the UE communications manager 615 may include a packet component 620, a sequence component 625, a link component 630, and a cell component 635.
  • the UE communications manager 615 may be an example of aspects of the UE communications manager 810 described herein.
  • the packet component 620 may receive a packet associated with a PDCP sequence number.
  • the sequence component 625 may determine that the PDCP sequence number satisfies a PDCP sequence number hopping threshold.
  • the link component 630 may determine a radio link failure condition based on the PDCP sequence number satisfying the PDCP sequence number hopping threshold.
  • the cell component 635 may switch from operating in a first RAT to operating in a second RAT based on the radio link failure condition.
  • the transmitter 640 may transmit signals generated by other components of the device 605.
  • the transmitter 640 may be collocated with a receiver 610 in a transceiver module.
  • the transmitter 640 may be an example of aspects of the transceiver 820 described with reference to FIG. 8.
  • the transmitter 640 may utilize a single antenna or a set of antennas.
  • FIG. 7 shows a diagram 700 of a UE communications manager 705 that supports recovering from a data stall in wireless communications systems in accordance with aspects of the present disclosure.
  • the UE communications manager 705 may be an example of aspects of a UE communications manager 515, a UE communications manager 615, or a UE communications manager 810 described herein.
  • the UE communications manager 705 may include a packet component 710, a sequence component 715, a link component 720, a cell component 725, a service component 730, and a transfer component 735. Each of these modules may communicate, directly or indirectly, with one another (e.g., via one or more buses) .
  • the packet component 710 may receive a packet associated with a PDCP sequence number. In some examples, the packet component 710 may receive the packet from a first base station associated with the first RAT. In some cases, the packet includes a NR-type PDCP service data unit. The sequence component 715 may determine that the PDCP sequence number satisfies a PDCP sequence number hopping threshold. In some examples, the sequence component 715 may determine a difference between the PDCP sequence number associated with the received packet and a previous PDCP sequence number associated with a previously received packet. In some examples, the sequence component 715 may determine that the difference satisfies the PDCP sequence number hopping threshold. In some examples, the sequence component 715 may determine that the difference is greater than the PDCP sequence number hopping threshold.
  • the sequence component 715 may update a value of the PDCP sequence number hopping threshold based on triggering a TAU to a cell associated with the second RAT. In some examples, the sequence component 715 may increase the value of the PDCP sequence number hopping threshold based on a defined value. In some cases, the received packet corresponds to a first slot and the previously received packet corresponds to a second slot preceding the first slot. The link component 720 may determine a radio link failure condition based on the PDCP sequence number satisfying the PDCP sequence number hopping threshold.
  • the cell component 725 may switch from operating in a first RAT to operating in a second RAT based on the radio link failure condition. In some examples, the cell component 725 may switch from operating in a standalone mode to operating in a non-standalone mode based on determining that the PDCP sequence number associated with the received packet satisfies the PDCP sequence number hopping threshold. In some examples, the cell component 725 may transmit a TAU request message to a second base station based on switching from operating in the standalone mode to operating in the non-standalone mode.
  • the cell component 725 may receive a TAU response message from the second base station based on the transmitted TAU request message, where switching from operating in the first RAT to operating in the second RAT is based on the received TAU response message from the second base station.
  • TAU response message includes a TAU accept.
  • the cell component 725 may camp on a cell associated with the second base station while operating in the non-standalone mode. In some examples, the cell component 725 may camp on a cell associated with the first base station while operating in a standalone mode. In some examples, the cell component 725 may operate in the second RAT while operating in a non-standalone mode. In some examples, the cell component 725 may operate exclusively in the second RAT based on switching from operating in the first RAT to operating in the second RAT. In some cases, the TAU request message includes dual-connectivity NR capability information. In some cases, the first RAT includes 5G NR and the second RAT includes 4G LTE.
  • the service component 730 may transmit a service request message to the second base station for packet-switched data transfer based on the received TAU response message from the second base station.
  • the transfer component 735 may transfer packet-switched data between the UE and the second base station based on the transmitted service request message.
  • FIG. 8 shows a diagram of a system 800 including a device 805 that supports recovering from a data stall in wireless communications systems in accordance with aspects of the present disclosure.
  • the device 805 may be an example of or include the components of device 505, device 605, or a UE 115 as described herein.
  • the device 805 may include components for bi-directional voice and data communications including components for transmitting and receiving communications, including a UE communications manager 810, an I/O controller 815, a transceiver 820, an antenna 825, memory 830, and a processor 840. These components may be in electronic communication via one or more buses (e.g., bus 845) .
  • buses e.g., bus 845
  • the UE communications manager 810 may receive a packet associated with a PDCP sequence number, determine that the PDCP sequence number satisfies a PDCP sequence number hopping threshold, determine a radio link failure condition based on the PDCP sequence number satisfying the PDCP sequence number hopping threshold, and switch from operating in a first RAT to operating in a second RAT based on the radio link failure condition.
  • the UE communications manager 810 may effectively implement recovery from a delay or an interruption in wireless communications (e.g., a data stall) . At least one implementation may enable the UE communications manager 810 to determine that a PDCP sequence number associated with a received PDU satisfies a PDCP sequence number hopping threshold. Based on implementing the PDCP sequence number hopping threshold as described herein, one or more processors of the device 805 (e.g., processor (s) controlling or incorporated with the UE communications manager 810) may experience reduce power consumption and promote high reliability and low latency wireless communications, among other benefits.
  • processors of the device 805 e.g., processor (s) controlling or incorporated with the UE communications manager 810 may experience reduce power consumption and promote high reliability and low latency wireless communications, among other benefits.
  • the I/O controller 815 may manage input and output signals for the device 805.
  • the I/O controller 815 may also manage peripherals not integrated into the device 805.
  • the I/O controller 815 may represent a physical connection or port to an external peripheral.
  • the I/O controller 815 may utilize an operating system such as or another known operating system.
  • the I/O controller 815 may represent or interact with a modem, a keyboard, a mouse, a touchscreen, or a similar device.
  • the I/O controller 815 may be implemented as part of a processor.
  • a user may interact with the device 805 via the I/O controller 815 or via hardware components controlled by the I/O controller 815.
  • the transceiver 820 may communicate bi-directionally, via one or more antennas, wired, or wireless links as described above.
  • the transceiver 820 may represent a wireless transceiver and may communicate bi-directionally with another wireless transceiver.
  • the transceiver 820 may also include a modem to modulate the packets and provide the modulated packets to the antennas for transmission, and to demodulate packets received from the antennas.
  • the device 805 may include a single antenna 825. However, in some cases, the device 805 may have more than one antenna 825, which may be capable of concurrently transmitting or receiving multiple wireless transmissions.
  • the memory 830 may include RAM and ROM.
  • the memory 830 may store computer-readable, computer-executable code 835 including instructions that, when executed, cause the processor 840 to perform various functions described herein.
  • the memory 830 may include, among other things, a BIOS which may control basic hardware or software operation such as the interaction with peripheral components or devices.
  • the code 835 may include instructions to implement aspects of the present disclosure, including instructions to support wireless communications.
  • the code 835 may be stored in a non-transitory computer-readable medium such as system memory or other type of memory.
  • the code 835 may not be directly executable by the processor 840 but may cause a computer (e.g., when compiled and executed) to perform functions described herein.
  • the processor 840 may include an intelligent hardware device, (e.g., a general-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, an FPGA, a programmable logic device, a discrete gate or transistor logic component, a discrete hardware component, or any combination thereof) .
  • the processor 840 may be configured to operate a memory array using a memory controller.
  • a memory controller may be integrated into the processor 840.
  • the processor 840 may be configured to execute computer-readable instructions stored in a memory (e.g., the memory 830) to cause the device 805 to perform various functions (e.g., functions or tasks supporting recovering from a data stall in wireless communications systems) .
  • FIG. 9 shows a flowchart illustrating a method 900 that supports recovering from a data stall in wireless communications systems in accordance with aspects of the present disclosure.
  • the operations of method 900 may be implemented by a UE 115 or its components as described herein.
  • the operations of method 900 may be performed by a UE communications manager as described with reference to FIGs. 5 through 8.
  • a UE may execute a set of instructions to control the functional elements of the UE to perform the functions described below.
  • a UE may perform aspects of the functions described below using special-purpose hardware.
  • the UE may receive a packet associated with a PDCP sequence number.
  • the operations of 905 may be performed according to the methods described herein. In some examples, aspects of the operations of 905 may be performed by a packet component as described with reference to FIGs. 5 through 8.
  • the UE may determine that the PDCP sequence number satisfies a PDCP sequence number hopping threshold.
  • the operations of 910 may be performed according to the methods described herein. In some examples, aspects of the operations of 910 may be performed by a sequence component as described with reference to FIGs. 5 through 8.
  • the UE may determine a radio link failure condition based on the PDCP sequence number satisfying the PDCP sequence number hopping threshold.
  • the operations of 915 may be performed according to the methods described herein. In some examples, aspects of the operations of 915 may be performed by a link component as described with reference to FIGs. 5 through 8.
  • the UE may switch from operating in a first RAT to operating in a second RAT based on the radio link failure condition.
  • the operations of 920 may be performed according to the methods described herein. In some examples, aspects of the operations of 920 may be performed by a cell component as described with reference to FIGs. 5 through 8.
  • FIG. 10 shows a flowchart illustrating a method 1000 that supports recovering from a data stall in wireless communications systems in accordance with aspects of the present disclosure.
  • the operations of method 1000 may be implemented by a UE 115 or its components as described herein.
  • the operations of method 1000 may be performed by a UE communications manager as described with reference to FIGs. 5 through 8.
  • a UE may execute a set of instructions to control the functional elements of the UE to perform the functions described below.
  • a UE may perform aspects of the functions described below using special-purpose hardware.
  • the UE may receive a packet associated with a PDCP sequence number.
  • the operations of 1005 may be performed according to the methods described herein. In some examples, aspects of the operations of 1005 may be performed by a packet component as described with reference to FIGs. 5 through 8.
  • the UE may determine that the PDCP sequence number satisfies a PDCP sequence number hopping threshold.
  • the operations of 1010 may be performed according to the methods described herein. In some examples, aspects of the operations of 1010 may be performed by a sequence component as described with reference to FIGs. 5 through 8.
  • the UE may determine a radio link failure condition based on the PDCP sequence number satisfying the PDCP sequence number hopping threshold.
  • the operations of 1015 may be performed according to the methods described herein. In some examples, aspects of the operations of 1015 may be performed by a link component as described with reference to FIGs. 5 through 8.
  • the UE may switch from operating in a standalone mode to operating in a non-standalone mode based on determining that the PDCP sequence number associated with the received packet satisfies the PDCP sequence number hopping threshold.
  • the operations of 1020 may be performed according to the methods described herein. In some examples, aspects of the operations of 1020 may be performed by a cell component as described with reference to FIGs. 5 through 8.
  • the UE may switch from operating in a first RAT to operating in a second RAT based on the radio link failure condition while operating in the standalone mode.
  • the operations of 1025 may be performed according to the methods described herein. In some examples, aspects of the operations of 1025 may be performed by a cell component as described with reference to FIGs. 5 through 8.
  • FIG. 11 shows a flowchart illustrating a method 1100 that supports recovering from a data stall in wireless communications systems in accordance with aspects of the present disclosure.
  • the operations of method 1100 may be implemented by a UE 115 or its components as described herein.
  • the operations of method 1100 may be performed by a UE communications manager as described with reference to FIGs. 5 through 8.
  • a UE may execute a set of instructions to control the functional elements of the UE to perform the functions described below.
  • a UE may perform aspects of the functions described below using special-purpose hardware.
  • the UE may receive a packet associated with a PDCP sequence number.
  • the operations of 1105 may be performed according to the methods described herein. In some examples, aspects of the operations of 1105 may be performed by a packet component as described with reference to FIGs. 5 through 8.
  • the UE may determine that the PDCP sequence number satisfies a PDCP sequence number hopping threshold.
  • the operations of 1110 may be performed according to the methods described herein. In some examples, aspects of the operations of 1110 may be performed by a sequence component as described with reference to FIGs. 5 through 8.
  • the UE may determine a radio link failure condition based on the PDCP sequence number satisfying the PDCP sequence number hopping threshold.
  • the operations of 1115 may be performed according to the methods described herein. In some examples, aspects of the operations of 1115 may be performed by a link component as described with reference to FIGs. 5 through 8.
  • the UE may transmit a TAU request message to a second base station based on switching from operating in a standalone mode to operating in a non-standalone mode and in response to the radio link failure condition.
  • the operations of 1120 may be performed according to the methods described herein. In some examples, aspects of the operations of 1120 may be performed by a cell component as described with reference to FIGs. 5 through 8.
  • the UE may receive a TAU response message from the second base station based on the transmitted TAU request message.
  • the operations of 1125 may be performed according to the methods described herein. In some examples, aspects of the operations of 1125 may be performed by a cell component as described with reference to FIGs. 5 through 8.
  • the UE may switch from operating in a first RAT to operating in a second RAT based on the received TAU response message from the second base station.
  • the operations of 1130 may be performed according to the methods described herein. In some examples, aspects of the operations of 1130 may be performed by a cell component as described with reference to FIGs. 5 through 8.
  • LTE, LTE-A, LTE-APro, or NR may be described for purposes of example, and LTE, LTE-A, LTE-APro, or NR terminology may be used in much of the description, the techniques described herein are applicable beyond LTE, LTE-A, LTE-APro, or NR networks.
  • the described techniques may be applicable to various other wireless communications systems such as Ultra Mobile Broadband (UMB) , Institute of Electrical and Electronics Engineers (IEEE) 802.11 (Wi-Fi) , IEEE 802.16 (WiMAX) , IEEE 802.20, Flash-OFDM, as well as other systems and radio technologies not explicitly mentioned herein.
  • UMB Ultra Mobile Broadband
  • IEEE Institute of Electrical and Electronics Engineers
  • Wi-Fi Institute of Electrical and Electronics Engineers
  • WiMAX IEEE 802.16
  • IEEE 802.20 Flash-OFDM
  • Information and signals described herein may be represented using any of a variety of different technologies and techniques.
  • data, instructions, commands, information, signals, bits, symbols, and chips that may be referenced throughout the description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.
  • a general-purpose processor may be a microprocessor, but in the alternative, the processor may be any processor, controller, microcontroller, or state machine.
  • a processor may also be implemented as a combination of computing devices (e.g., a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration) .
  • the functions described herein may be implemented in hardware, software executed by a processor, firmware, or any combination thereof. If implemented in software executed by a processor, the functions may be stored on or transmitted over as one or more instructions or code on a computer-readable medium. Other examples and implementations are within the scope of the disclosure and appended claims. For example, due to the nature of software, functions described herein may be implemented using software executed by a processor, hardware, firmware, hardwiring, or combinations of any of these. Features implementing functions may also be physically located at various positions, including being distributed such that portions of functions are implemented at different physical locations.
  • Computer-readable media includes both non-transitory computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another.
  • a non-transitory storage medium may be any available medium that may be accessed by a general-purpose or special purpose computer.
  • non-transitory computer-readable media may include random-access memory (RAM) , read-only memory (ROM) , electrically erasable programmable ROM (EEPROM) , flash memory, compact disk (CD) ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other non-transitory medium that may be used to carry or store desired program code means in the form of instructions or data structures and that may be accessed by a general-purpose or special-purpose computer, or a general-purpose or special-purpose processor. Also, any connection is properly termed a computer-readable medium.
  • RAM random-access memory
  • ROM read-only memory
  • EEPROM electrically erasable programmable ROM
  • flash memory compact disk (CD) ROM or other optical disk storage
  • CD compact disk
  • magnetic disk storage or other magnetic storage devices or any other non-transitory medium that may be used to carry or store desired program code means in the form of instructions or data structures and that may be accessed by a general-purpose or special-purpose computer,
  • Disk and disc include CD, laser disc, optical disc, digital versatile disc (DVD) , floppy disk and Blu-ray disc where disks usually reproduce data magnetically, while discs reproduce data optically with lasers. Combinations of the above are also included within the scope of computer-readable media.
  • the functions described herein may be implemented in hardware, software executed by a processor, firmware, or any combination thereof. If implemented in software executed by a processor, the functions may be stored on or transmitted over as one or more instructions or code on a computer-readable medium. Other examples and implementations are within the scope and spirit of the disclosure and appended claims. For example, due to the nature of software, functions described above can be implemented using software executed by a processor, hardware, firmware, hardwiring, or combinations of any of these. Features implementing functions may also be physically located at various positions, including being distributed such that portions of functions are implemented at different physical locations.
  • the term “and/or, ” when used in a list of two or more items means that any one of the listed items can be employed by itself, or any combination of two or more of the listed items can be employed.
  • the composition can contain A alone; B alone; C alone; A and B in combination; A and C in combination; B and C in combination; or A, B, and C in combination.
  • “or” as used in a list of items indicates a disjunctive list such that, for example, a list of “at least one of A, B, or C” means A or B or C or AB or AC or BC or ABC (i.e., A and B and C) .

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  • Mobile Radio Communication Systems (AREA)

Abstract

Procédés, systèmes et dispositifs de communication sans fil. Un dispositif de communication, autrement dit un équipement utilisateur (UE), peut recevoir un paquet associé à un numéro de séquence de protocole PDCP. L'UE peut déterminer que le numéro de séquence de protocole PDCP satisfait un seuil de saut de numéro de séquence de protocole PDCP, et déterminer une condition de défaillance de liaison radio sur la base du numéro de séquence de protocole PDCP satisfaisant le seuil de saut de numéro de séquence de protocole PDCP. Une condition de défaillance de liaison radio peut, par exemple, provoquer un décrochage de données pour l'UE, qui affecte les fonctionnements ou services au niveau de l'UE. L'UE peut commuter d'un fonctionnement dans une première technologie d'accès radio (RAT) pour fonctionner dans une seconde RAT sur la base de l'état de défaillance de liaison radio. L'UE peut ainsi récupérer du décrochage de données lorsqu'il se trouve sur une cellule dans un système de communication sans fil.
PCT/CN2020/090447 2020-05-15 2020-05-15 Récupération d'un décrochage de données dans des systèmes de communication sans fil WO2021226987A1 (fr)

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Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20130182563A1 (en) * 2012-01-18 2013-07-18 Mediatek, Inc. Method of Enhanced Connection Recovery and Loss-less DATA Recovery
CN105723668A (zh) * 2013-10-30 2016-06-29 高通股份有限公司 用于聚集来自wwan和wlan的数据的技术
US20180279168A1 (en) * 2017-03-24 2018-09-27 Mediatek Inc. User equipment and methods for pdcp duplication in 5g ran
WO2018203794A1 (fr) * 2017-05-04 2018-11-08 Telefonaktiebolaget Lm Ericsson (Publ) Procédé et appareil de détection de messages de signalisation de commande retardés ou perdus

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20130182563A1 (en) * 2012-01-18 2013-07-18 Mediatek, Inc. Method of Enhanced Connection Recovery and Loss-less DATA Recovery
CN105723668A (zh) * 2013-10-30 2016-06-29 高通股份有限公司 用于聚集来自wwan和wlan的数据的技术
US20180279168A1 (en) * 2017-03-24 2018-09-27 Mediatek Inc. User equipment and methods for pdcp duplication in 5g ran
WO2018203794A1 (fr) * 2017-05-04 2018-11-08 Telefonaktiebolaget Lm Ericsson (Publ) Procédé et appareil de détection de messages de signalisation de commande retardés ou perdus

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
CATT: "Discussion on PDCP Duplication for EN-DC[C056]", 3GPP DRAFT; R2-1810496 DISCUSSION ON PDCP DUPLICATION FOR EN-DC [C056], 3RD GENERATION PARTNERSHIP PROJECT (3GPP), MOBILE COMPETENCE CENTRE ; 650, ROUTE DES LUCIOLES ; F-06921 SOPHIA-ANTIPOLIS CEDEX ; FRANCE, vol. RAN WG2, no. Montreal, Canada; 20180702 - 20180706, 1 July 2018 (2018-07-01), Mobile Competence Centre ; 650, route des Lucioles ; F-06921 Sophia-Antipolis Cedex ; France , XP051467657 *
LG ELECTRONICS INC.: "PDCP SN gap issue in fast MCG link recovery", 3GPP DRAFT; R2-1913839_PDCP SN GAP ISSUE IN FAST MCG LINK RECOVERY_R2, 3RD GENERATION PARTNERSHIP PROJECT (3GPP), MOBILE COMPETENCE CENTRE ; 650, ROUTE DES LUCIOLES ; F-06921 SOPHIA-ANTIPOLIS CEDEX ; FRANCE, vol. RAN WG2, no. Chongqing, China; 20191014 - 20191018, 4 October 2019 (2019-10-04), Mobile Competence Centre ; 650, route des Lucioles ; F-06921 Sophia-Antipolis Cedex ; France , XP051791830 *
MEDIATEK INC.: "PDCP uplink path switching", 3GPP DRAFT; R2-1711547 UPLINK PATH SWITCHING, 3RD GENERATION PARTNERSHIP PROJECT (3GPP), MOBILE COMPETENCE CENTRE ; 650, ROUTE DES LUCIOLES ; F-06921 SOPHIA-ANTIPOLIS CEDEX ; FRANCE, vol. RAN WG2, no. Prague, Czech Republic; 20171009 - 20171013, 8 October 2017 (2017-10-08), Mobile Competence Centre ; 650, route des Lucioles ; F-06921 Sophia-Antipolis Cedex ; France , XP051343517 *

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