Patent Description:
The following abbreviations are herewith defined, at least some of which are referred to within the following description: Third Generation Partnership Project ("3GPP"), <NUM> QoS Indicator ("5QI"), Acknowledge Mode ("AM"), Backhaul ("BH"), Broadcast Multicast ("BM"), Buffer Occupancy ("BO"), Base Station ("BS"), Buffer Status Report ("BSR"), Bandwidth Part ("BWP"), Component Carrier ("CC"), Control Element ("CE"), Coordinated Multipoint ("CoMP"), Categories of Requirements ("CoR"), Control Plane ("CP"), CSI-RS Resource Indicator ("CRI"), Cell RNTI ("C-RNTI"), Channel State Information ("CSI"), Channel Quality Indicator ("CQI"), Central Unit ("CU"), Codeword ("CW"), Downlink ("DL"), Demodulation Reference Signal ("DMRS"), Data Radio Bearer ("DRB"), Dedicated Short-Range Communications ("DSRC"), Distributed Unit ("DU"), Enhanced Mobile Broadband ("eMBB"), Evolved Node B ("eNB"), Enhanced Subscriber Identification Module ("eSIM"), Enhanced ("E"), Frequency Division Duplex ("FDD"), Frequency Division Multiple Access ("FDMA"), Frequency Range ("FR"), Hybrid Automatic Repeat Request ("HARQ"), Integrated Access Backhaul ("IAB"), Identity or Identifier or Identification ("ID"), Interference Measurement ("IM"), International Mobile Subscriber Identity ("IMSI"), Internet-of-Things ("IoT"), Internet Protocol ("IP"), Joint Transmission ("JT"), Level <NUM> ("L1"), Logical Channel ("LCH"), Logical Channel Group ("LCG"), Logical Channel ID ("LCID"), Logical Channel Prioritization ("LCP"), Long Term Evolution ("LTE"), Levels of Automation ("LoA"), Medium Access Control ("MAC"), Modulation Coding Scheme ("MCS"), Multiple Input Multiple Output ("MIMO"), Mobile-Termination ("MT"), Machine Type Communication ("MTC"), Multi-User MIMO ("MU-MIMO"), Negative-Acknowledgment ("NACK") or ("NAK"), Next Generation ("NG"), Next Generation Node B ("gNB"), New Radio ("NR"), Non-Zero Power ("NZP"), Orthogonal Frequency Division Multiplexing ("OFDM"), Peak-to-Average Power Ratio ("PAPR"), Physical Broadcast Channel ("PBCH"), Physical Downlink Shared Channel ("PDSCH"), Policy Control Function ("PCF"), Packet Data Convergence Protocol ("PDCP"), Packet Data Network ("PDN"), Protocol Data Unit ("PDU"), Public Land Mobile Network ("PLMN"), Precoding Matrix Indicator ("PMI"), ProSe Per Packet Priority ("PPPP"), ProSe Per Packet Reliability ("PPPR"), Packet Switched ("PS"), Physical Sidelink Control Channel ("PSCCH"), Physical Sidelink Shared Channel ("PSSCH"), Quasi Co-Located ("QCL"), Quality of Service ("QoS"), Random Access Channel ("RACH"), Radio Access Network ("RAN"), Radio Access Technology ("RAT"), Resource Element ("RE"), Rank Indicator ("RI"), Radio Link Control ("RLC"), Radio Link Failure ("RLF"), Radio Network Temporary Identifier ("RNTI"), Resource Pool ("RP"), Radio Resource Control ("RRC"), Reference Signal ("RS"), Reference Signal Received Power ("RSRP"), Reference Signal Received Quality ("RSRQ"), Receive ("RX"), Secondary Cell ("SCell"), Sub Carrier Spacing ("SCS"), Service Data Unit ("SDU"), Subscriber Identity Module ("SIM"), Signal-to-Interference and Noise Ratio ("SINR"), Sidelink ("SL"), Sequence Number ("SN"), Scheduling Request ("SR"), Synchronization Signal ("SS"), SS/PBCH Block ("SSB"), Time Division Duplex ("TDD"), Temporary Mobile Subscriber Identity ("TMSI"), Transmission Reception Point ("TRP"), Transmit ("TX"), User Entity/Equipment (Mobile Terminal) ("UE"), Universal Integrated Circuit Card ("UICC"), Uplink ("UL"), Unacknowledged Mode ("UM"), Universal Mobile Telecommunications System ("UMTS"), User Plane ("UP"), Universal Subscriber Identity Module ("USIM"), Universal Terrestrial Radio Access Network ("UTRAN"), Vehicle to Everything ("V2X"), Voice Over IP ("VoIP"), Visited Public Land Mobile Network ("VPLMN"), Vehicle RNTI ("V-RNTI"), and Worldwide Interoperability for Microwave Access ("WiMAX"). As used herein, "HARQ-ACK" may represent collectively the Positive Acknowledge ("ACK") and the Negative Acknowledge ("NAK"). ACK means that a TB is correctly received while NAK means a TB is erroneously received.

In certain wireless communications networks, sidelink communications may be used. In such networks, sidelink communications may use one radio access technology and network communications may use another radio access technology.

<CIT> describes a first protocol stack used to implement communication between a base station and a user equipment on a base station side, and a second protocol stack used to implement communication between devices, whereby the second protocol stack is connected to the at least one protocol layer of the first protocol stack.

Claim <NUM> defines a method, claim <NUM> defines an apparatus and claim <NUM> defines a processor for wireless communication. In the following, any method and/or apparatus referred to as embodiments but nevertheless do not fall within the scope of the appended claims are to be understood as examples helpful in understanding the invention.

Methods for sidelink communication using multiple protocol stacks are disclosed. Apparatuses and systems also perform the functions of the apparatus. In one embodiment, the method includes assigning a first protocol stack of a device to network communications. In certain embodiments, the method includes assigning a second protocol stack of the device to sidelink communications. In various embodiments, the method includes generating, at the second protocol stack, first information based on arrival of data in a sidelink logical channel. In some embodiments, the method includes transmitting the first information from the second protocol stack to a network device via the first protocol stack.

An apparatus for sidelink communication using multiple protocol stacks, in one embodiment, includes a processor that: assigns a first protocol stack of the apparatus to network communications; assigns a second protocol stack of the apparatus to sidelink communications; and generates, at the second protocol stack, first information based on arrival of data in a sidelink logical channel. In various embodiments, the apparatus includes a transmitter that transmits the first information from the second protocol stack to a network device via the first protocol stack.

<FIG> depicts an embodiment of a wireless communication system <NUM> for sidelink communication using multiple protocol stacks. In one embodiment, the wireless communication system <NUM> includes remote units <NUM> and network units <NUM>. Even though a specific number of remote units <NUM> and network units <NUM> are depicted in <FIG>, one of skill in the art will recognize that any number of remote units <NUM> and network units <NUM> may be included in the wireless communication system <NUM>.

In one embodiment, the remote units <NUM> may include computing devices, such as desktop computers, laptop computers, personal digital assistants ("PDAs"), tablet computers, smart phones, smart televisions (e.g., televisions connected to the Internet), set-top boxes, game consoles, security systems (including security cameras), vehicle on-board computers, network devices (e.g., routers, switches, modems), IoT devices, or the like. In some embodiments, the remote units <NUM> include wearable devices, such as smart watches, fitness bands, optical headmounted displays, or the like. The remote units <NUM> may communicate directly with one or more of the network units <NUM> via UL communication signals and/or the remote units <NUM> may communicate directly with other remote units <NUM> via sidelink communication.

In certain embodiments, a network unit <NUM> may also be referred to as an access point, an access terminal, a base, a base station, a Node-B, an eNB, a gNB, a Home Node-B, a RAN, a relay node, a device, a network device, an IAB node, a donor IAB node, or by any other terminology used in the art.

In one implementation, the wireless communication system <NUM> is compliant with the <NUM> or NG (Next Generation) of the 3GPP protocol, wherein the network unit <NUM> transmits using NG RAN technology. More generally, however, the wireless communication system <NUM> may implement some other open or proprietary communication protocol, for example, WiMAX, among other protocols.

In various embodiments, a remote unit <NUM> may assign a first protocol stack of the remote unit <NUM> to network communications. In certain embodiments, the remote unit <NUM> may assign a second protocol stack of the remote unit <NUM> to sidelink communications. In various embodiments, the remote unit <NUM> may generate, at the second protocol stack, first information based on arrival of data in a sidelink logical channel. In some embodiments, the remote unit <NUM> may transmit the first information from the second protocol stack to a network device (e.g., the network unit <NUM>) via the first protocol stack. Accordingly, a remote unit <NUM> may be used for sidelink communication using multiple protocol stacks.

In some embodiments, a network unit <NUM> may transmit information to a first remote unit <NUM> that is used by the first remote unit <NUM> for accomplishing communication to a second remote unit <NUM>. The communication between the network unit <NUM> and the first remote unit <NUM> uses a first RAT and the communication between the first remote unit <NUM> and the second remote unit <NUM> uses a second RAT.

<FIG> depicts one embodiment of an apparatus <NUM> that may be used for sidelink communication using multiple protocol stacks. The apparatus <NUM> includes one embodiment of the remote unit <NUM>. Furthermore, the remote unit <NUM> may include a processor <NUM>, a memory <NUM>, an input device <NUM>, a display <NUM>, a transmitter <NUM>, and a receiver <NUM>. In some embodiments, the input device <NUM> and the display <NUM> are combined into a single device, such as a touchscreen. In certain embodiments, the remote unit <NUM> may not include any input device <NUM> and/or display <NUM>. In various embodiments, the remote unit <NUM> may include one or more of the processor <NUM>, the memory <NUM>, the transmitter <NUM>, and the receiver <NUM>, and may not include the input device <NUM> and/or the display <NUM>.

In various embodiments, the processor <NUM> assigns a first protocol stack of the remote unit <NUM> to network communications; assigns a second protocol stack of the remote unit <NUM> to sidelink communications; and generates, at the second protocol stack, first information based on arrival of data in a sidelink logical channel.

The transmitter <NUM> is used to provide UL communication signals to the network unit <NUM> and the receiver <NUM> is used to receive DL communication signals from the network unit <NUM>. In one embodiment, the transmitter <NUM> transmits the first information from the second protocol stack to a network device via the first protocol stack.

<FIG> depicts one embodiment of an apparatus <NUM> that may be used for sidelink communication using multiple protocol stacks. The apparatus <NUM> includes one embodiment of the network unit <NUM>. Furthermore, the network unit <NUM> may include a processor <NUM>, a memory <NUM>, an input device <NUM>, a display <NUM>, a transmitter <NUM>, and a receiver <NUM>. As may be appreciated, the processor <NUM>, the memory <NUM>, the input device <NUM>, the display <NUM>, the transmitter <NUM>, and the receiver <NUM> may be substantially similar to the processor <NUM>, the memory <NUM>, the input device <NUM>, the display <NUM>, the transmitter <NUM>, and the receiver <NUM> of the remote unit <NUM>, respectively.

Although only one transmitter <NUM> and one receiver <NUM> are illustrated, the network unit <NUM> may have any suitable number of transmitters <NUM> and receivers <NUM>.

<FIG> is a schematic block diagram illustrating one embodiment of a system <NUM> for sidelink communication using multiple protocol stacks. The system <NUM> includes one embodiment of the remote unit <NUM> as described herein. Moreover, the remote unit <NUM> includes a first protocol stack <NUM> (e.g., a Uu protocol stack - i.e., a protocol stack for communications between a UE and an eNB and/or gNB) and a second protocol stack <NUM> (e.g., a sidelink protocol stack). The first protocol stack <NUM> may be used for first RAT communications (e.g., network communications) and the second protocol stack <NUM> may be used for second RAT communications (e.g., sidelink communications). The first RAT and the second RAT may be different from one another.

The first protocol stack <NUM> includes a PDCP layer <NUM>, an RLC layer <NUM>, a MAC layer <NUM>, and a physical layer <NUM> all corresponding to the first RAT communications. Further, the second protocol stack <NUM> includes a PDCP layer <NUM>, an RLC layer <NUM>, a MAC layer <NUM>, and a physical layer <NUM> all corresponding to the second RAT communications.

As illustrated, the first protocol stack <NUM> may transmit and/or receive communications <NUM> with the second protocol stack <NUM>. The system <NUM> includes a network device <NUM> (e.g., network unit <NUM>). The first protocol stack <NUM> may transmit and/or receive communications <NUM> with the network device <NUM> using the first RAT via a Uu interface (i.e., a communication interface between a UE and an eNB and/or a gNB, such as an LTE Uu interface or an NR Uu interface). Further, the system <NUM> includes a sidelink device <NUM> (e.g., remote unit <NUM>). The second protocol stack <NUM> may transmit and/or receive communications <NUM> with the sidelink device <NUM> using the second RAT. Thus, the remote unit <NUM> (e.g., a UE) may request sidelink resources on the first RAT (e.g., serving RAT) for V2X transmissions on the second RAT (e.g., a non-serving RAT) and enable the network device <NUM> (e.g., a serving RAN) to control resource grant to the remote unit <NUM> using the first RAT. It should be noted that sidelink communication described herein may be LTE sidelink communication or NR sidelink communication.

In one embodiment, a remote unit <NUM> interested in performing sidelink communication on a second RAT may inform the network device <NUM> about its interest in performing sidelink communication. The network device <NUM> may then in turn configure the remote unit <NUM> with necessary configuration information such as: LCG IDs specific to sidelink logical channels of the second RAT, a RNTI specific to accomplish communication (e.g., receiving a sidelink second RAT specific DCI) with the second protocol stack <NUM>, etc..

In one embodiment, a BSR may be triggered in the MAC layer <NUM> of the second protocol stack <NUM>. The BSR may be reported from the MAC layer <NUM> of the second protocol stack <NUM> to the network device <NUM> via the MAC layer <NUM> of the first protocol stack <NUM>. In certain embodiments, a SL grant may be indicated from the physical layer <NUM> of the first protocol stack <NUM> to the physical layer <NUM> of the second protocol stack <NUM>. The physical layer <NUM> of the second protocol stack <NUM> may indicate the SL grant to the MAC layer <NUM> of the second protocol stack <NUM>. In various embodiments, a SL grant may be indicated directly from the physical layer <NUM> of the first protocol stack <NUM> to the MAC layer <NUM> of the second protocol stack <NUM>. In some embodiments, the second protocol stack <NUM> may be activated in the remote unit <NUM> in response to data from an application using sidelink transmission over the second RAT arriving at or above layer <NUM> of the first protocol stack <NUM> (e.g., at or above the PDCP layer <NUM>, the RLC layer <NUM>, or the MAC layer <NUM>). The application may send an indication from an upper layer including V2X application and control layers and the NAS protocol based on the application's QoS requirements and the indication may indicate that the application is using sidelink transmission on a second RAT.

In certain embodiments, the second protocol stack <NUM> may be configured with triggers for sending a BSR. The triggers for sending the BSR may be monitored by the MAC layer <NUM> of the second protocol stack <NUM>. In various embodiments, the triggers for sending a BSR may include: data from a SL V2X logical channel becoming available for transmission - this may be regardless of priority rules for reporting a regular BSR; a time based trigger (e.g., periodically causing a trigger to occur if configured by the network. To enable this, the remote unit <NUM> may inform the network device <NUM> using RRC signaling that it may need to perform sidelink transmission on the second RAT and in response the network device <NUM> may configure the periodicity of BSR reporting and may allocate resources to the remote unit <NUM> that include resources for sending scheduling requests); adding and/or removing a bearer and/or a destination (e.g., the bearer and/or the destination may use sidelink V2X transmission in the second RAT); adding and/or removing a bearer for a cast-type (e.g., unicast, multicast, groupcast) - the bearer may use sidelink V2X transmission in the second RAT; and/or a change in vehicle location (e.g., vehicle moves into a different geographical zone, based on GPS coordinates and/or similar location change methods).

In various embodiments, the remote unit <NUM> may form a MAC CE for BSR reporting. In certain embodiments, a new MAC CE may be used to only report BO of SL logical channels terminating in the MAC layer <NUM> of the second protocol stack <NUM>. In some embodiments, a reserved logical channel ID may correspond to the new MAC CE. In one embodiment, the MAC CE format may be like the MAC CE format illustrated in Figure <NUM>. 1a of 3GPP TS <NUM>-f30.

In certain embodiments, multiple BSRs from one or more logical channels may be pending in the MAC layer <NUM> of the first protocol stack <NUM>. The network device <NUM> may need to know which of the BSRs corresponds to UL data and which of the BSRs corresponds to SL data so that the network device <NUM> can provide appropriate UL and SL grants. Accordingly, information regarding each BSR is provided to the network device <NUM> to indicate whether a corresponding BSR is for BO of UL data, BO of sidelink V2X on NR, or BO of sidelink V2X on LTE.

In various embodiments, different MAC CEs may be used to transmit information regarding each BSR provided to the network device <NUM>. In such embodiments, a unique MAC CE may indicate whether a corresponding BSR is for BO of UL data, BO of sidelink V2X on NR, or BO of sidelink V2X on LTE (e.g., <NUM> different MAC CEs).

In some embodiments, different LCG IDs may be used to transmit information regarding each BSR provided to the network device <NUM>. In such embodiments, separate LCGs may be used indicate whether a corresponding BSR is for BO of UL data, BO of sidelink V2X on NR, or BO of sidelink V2X on LTE (e.g., <NUM> different LCG IDs). For example, a first LCG ID may carry BO of sidelink V2X on NR, a second LCG ID may carry BO of sidelink V2X on LTE, and a third LCG ID may carry BO of UL data. In some embodiments, a total number of LCGs reported to be <NUM> or greater in LTE and/or <NUM> or greater in NR. The total number of LCGs may be greater than <NUM> in LTE and <NUM> in NR to accommodate multiple logical channels of sidelink V2X on NR and multiple logical channels on sidelink V2X on LTE. A mapping between an LCG ID and a type of data reported may be provided to the remote unit <NUM> by specification or network configuration (e.g., RRC signaling). In certain embodiments, a mapping between logical channels and LCG IDs may be provided to the remote unit <NUM> by specification or network configuration.

In various embodiments, a combination of different MAC CEs and LCG IDs may be used to transmit information regarding each BSR provided to the network device <NUM>. In such embodiments, a unique MAC CE may indicate whether a corresponding BSR is for UL or SL, and a LCG ID may indicate whether a SL BSR is for BO of sidelink V2X on NR or BO of sidelink V2X on LTE. A mapping between MAC CEs, LCG IDs, types of data, and/or logical channels may be provided to the remote unit <NUM> by specification or network configuration.

In some embodiments, the second protocol stack <NUM> may send one or more of the following to the first protocol stack <NUM>: an indication that data is available for transmission (e.g., BSR has been triggered in the second RAT); a BO when a BSR has been triggered (e.g., <NUM> bytes for LCG ID x and <NUM> bytes for LCG ID y); and a full BSR report that is only for a sidelink logical channel in the second RAT. Upon receiving one or more of the indication and the BO from the second protocol stack <NUM>, the first protocol stack <NUM> may prepare a combined BSR report. The combined BSR report may include BOs from the first protocol stack <NUM> and the BOs from the second protocol stack <NUM>. The first protocol stack <NUM> may query the second protocol stack <NUM> before sending the combined BSR report to the network device <NUM> to ensure that the latest BOs are reported. If the first protocol stack <NUM> only receives the full BSR report (e.g., sidelink BSR report) from the second protocol stack <NUM>, the first protocol stack <NUM> may forward the full BSR report to the network device <NUM>. In some embodiments, the first protocol stack <NUM> may send the full BSR report from the second protocol stack <NUM> together with a BSR report from the first protocol stack <NUM>.

<FIG> is a schematic block diagram illustrating one embodiment of a system <NUM> for network communication using multiple protocol stacks. The system <NUM> includes one embodiment of the remote unit <NUM> as described herein. Moreover, the remote unit <NUM> includes the first protocol stack <NUM> and the second protocol stack <NUM>. The first protocol stack <NUM> and the second protocol stack <NUM> are described in relation to <FIG>. The system <NUM> also includes the network device <NUM> that is also described in relation to <FIG>.

In some embodiments, the remote unit <NUM> may need to report a BSR to the network device <NUM>. In certain embodiments, the MAC layer <NUM> of the second protocol stack <NUM> may report via communications <NUM> one of the following to the MAC layer <NUM> of the first protocol stack <NUM>: an indication that new data is available for transmission (e.g., an indication that a SL BSR for the second RAT has triggered); or SL BOs (e.g., in bytes) of one or more LCGs and/or destination IDs. In embodiments in which the indication that new data is available for transmission is transmitted, the MAC layer <NUM> of the first protocol stack <NUM> may later request exact BOs from the MAC layer <NUM> of the second protocol stack <NUM> after an UL grant is received. In embodiments in which SL BOs are transmitted, the MAC layer <NUM> of the second protocol stack <NUM> may periodically update information corresponding to the SL BOs or the MAC layer <NUM> of the first protocol stack <NUM> may request the latest SL BO values after an UL grant is received and/or LCP is completed. In certain embodiments, the communications <NUM> may include one or more actual BOs, SL LCG IDs corresponding to BOs, one or more destination IDs, and/or a cast-type (e.g., unicast, multicast, groupcast). In various embodiments, the MAC layer <NUM> of the first protocol stack <NUM> may report via communications <NUM> BOs and/or BSRs to the network device <NUM>.

In some embodiments, a SR may be configured by the network device <NUM> and may be transmitted by the remote unit <NUM>. In certain embodiments, the SR may be configured so that the SR configuration may be used by one or more V2X logical channels. In various embodiments, the SR may be configured so that there are separate SR configurations for LTE sidelink V2X, NR sidelink V2X. In some embodiments, the SR may be configured so that there are separate SR configurations for specific bearers belonging to V2X logical channels. In certain embodiments, the SR may be configured so that there is: an SR configuration per UE (e.g., remote unit <NUM>); an SR configuration per SL RAT (e.g., LTE V2X BSR, NR V2X BSR); an SR configuration per destination ID (e.g., the destination ID may indicate cast information such as unicast, groupcast, and/or broadcast); an SR configuration per SL LCG; and/or an SR configuration per LCH.

In some embodiments, an SR may be configured so there is a separate SR configuration per UE and that only configured V2X logical channels can use the SR configuration. As may be appreciated, a SR may be triggered by the MAC layer <NUM> of the second protocol stack <NUM> for logical channels terminating in the MAC layer <NUM>. The MAC layer <NUM> of the second protocol stack <NUM> may indicate the trigger to the MAC layer <NUM> of the first protocol stack <NUM>. Moreover, the MAC layer <NUM> of the first protocol stack <NUM> may instruct the physical layer <NUM> of the first protocol stack <NUM> to use specific SR resources for SR transmission.

In certain embodiments, if no SR is configured for SL data to request an UL grant or if a configured maximum number of SR transmissions are made without receiving a SL grant (e.g., specific DCI with SL grant), then the MAC layer <NUM> of the first protocol stack <NUM> may trigger and/or run a RACH procedure on behalf of the MAC layer <NUM> of the second protocol stack <NUM>. In such embodiments, MsgA (e.g., in <NUM>-step RACH) or Msg3 (e.g., in <NUM>-step RACH) may include the SL BSR (e.g., BOs from SL logical channels from the second RAT) transmitted to the network device <NUM>.

In various embodiments, the remote unit <NUM> may attempt to receive SL grants for sidelink V2X communication using an RNTI configured for SL grants of the second RAT. In some embodiments, the remote unit <NUM> may attempt to receive SL grants for sidelink V2X communication using a new DCI format. In certain embodiments, the network device <NUM> may provide UL grants and/or SL grants directly if it can identify (e.g., based on an SR configuration) that data for a sidelink V2X channel is available for transmission. As used herein, the network device <NUM> may refer to a single network device, or multiple network devices (e.g., an eNB, a gNB, a RAN, a network, etc.).

<FIG> is a schematic block diagram illustrating another embodiment of a system <NUM> for network communication using multiple protocol stacks. The system <NUM> includes one embodiment of the remote unit <NUM> as described herein. Moreover, the remote unit <NUM> includes the first protocol stack <NUM> and the second protocol stack <NUM>. The first protocol stack <NUM> and the second protocol stack <NUM> are described in relation to <FIG>. The system <NUM> also includes the network device <NUM> that is also described in relation to <FIG>.

In some embodiments, in response to a SL grant being received (e.g., either dynamically or semi-persistently) via communications <NUM> from the network device <NUM> to the first protocol stack <NUM>, the physical layer <NUM> of the first protocol stack <NUM> may convey the SL grant to the physical layer <NUM> of the second protocol stack <NUM> via communications <NUM>. In such embodiments, the physical layer <NUM> of the second protocol stack <NUM> may convey the SL grant to the MAC layer <NUM> of the second protocol stack <NUM> via communications <NUM>.

<FIG> is a schematic block diagram illustrating a further embodiment of a system <NUM> for network communication using multiple protocol stacks. The system <NUM> includes one embodiment of the remote unit <NUM> as described herein. Moreover, the remote unit <NUM> includes the first protocol stack <NUM> and the second protocol stack <NUM>. The first protocol stack <NUM> and the second protocol stack <NUM> are described in relation to <FIG>. The system <NUM> also includes the network device <NUM> that is also described in relation to <FIG>.

In certain embodiments, in response to a SL grant being received (e.g., either dynamically or semi-persistently) via communications <NUM> from the network device <NUM> to the first protocol stack <NUM>, the physical layer <NUM> of the first protocol stack <NUM> may convey the SL grant directly to the MAC layer <NUM> of the second protocol stack <NUM> via communications <NUM>.

In various embodiments, if an UL grant is received by the remote unit <NUM>, the remote unit <NUM> may include one or more BSR MAC CEs to report BOs and/or BSRs for UL data, LTE V2X data, and/or NR V2X data. In some embodiments, the UL data BOs and/or BSRs are reported if the UL grant can accommodate all pending UL data BOs and/or BSRs available for transmission including the BSR MAC CEs corresponding to the UL data BOs and/or BSRs.

In certain embodiments, if a SL grant is received by the remote unit <NUM>, the remote unit <NUM> may cancel all pending sidelink V2X BSRs if the SL grant can accommodate all pending data available for transmission from SL V2X logical channels. In such embodiments, other non-SL V2X BSRs may be considered triggered and are not canceled (e.g., if the network provided resources only for sidelink communication on the second RAT (using an RNTI configured for this purpose in a DCI configured for this purpose) and no resources for UL (data or UL BSR) transmission is available then the BSR triggers for UL are considered as active and are therefore not cancelled).

In various embodiments, the remote unit <NUM> may perform a BO prioritization if an UL grant is inadequate to carry a complete BSR. In such embodiments, the UL grant may be addressed to C-RNTI, SL V-RNTI, or SL semi-persistent scheduling V-RNTI. The inadequacy may occur because: there are multiple BSR MAC CEs (e.g., one for each of UL data, SL data on LTE, and SL data on NR) available for transmission; there are separate BSR MAC CEs defined for each type of transmission and data is available for transmission corresponding to multiple types of transmission; or a size of BSR MAC CEs for sidelink V2X (e.g., combined for LTE and NR V2X sidelink) exceeds the grant size.

Prioritization, in certain embodiments, may be based on a logical channel priority, PPPP, PPPR, and/or 5QI assigned to bearers. In some embodiments, BOs in BSR MAC CEs may be reported in a decreasing priority order until a remaining size of an UL grant cannot accommodate the next BO.

In some embodiments, a V2X bearer from a first RAT may have a different QoS parameter compared to a V2X bearer from a second RAT. In such embodiments, a mapping table between logical channel priority, PPPP, PPPR, and/or 5QI may be determined and/or used. The mapping table may set an equivalence between different quality values (or value ranges). For example, the mapping table may indicate that PPPP-x = range [5QI-a to 5QI-b]. In certain embodiments, the mapping table may be specified, preconfigured in the remote unit <NUM>, configured by higher layers (e.g., V2X), and/or configured by the network device <NUM> by higher layers or RRC signaling.

In various embodiments, BOs reporting SL V2X on LTE may be prioritized over other BOs because such BOs may carry basic safety messages. In some embodiments, BOs reporting SL V2X on NR may be prioritized over other BOs because such BOs may carry advanced V2X messages. Prioritized BOs may be configured by the higher layers (e.g., V2X), and/or configured by the network device <NUM> by higher layers or RRC signaling.

In some embodiments, an existing "Sidelink BSR MAC Control Element" may be used without considering a logical channel priority, PPPP, PPR, and/or 5QI. In such embodiments, depending on the grant size, up to <NUM> BOs in NR (or <NUM> BOs in LTE) may be signaled and if there are additional BOs the remote unit <NUM> may indicate with another bit that there are additional BOs.

<FIG> is a schematic flow chart diagram illustrating one embodiment of a method <NUM> for sidelink communication using multiple protocol stacks. In some embodiments, the method <NUM> is performed by an apparatus, such as the remote unit <NUM>. In certain embodiments, the method <NUM> may be performed by a processor executing program code, for example, a microcontroller, a microprocessor, a CPU, a GPU, an auxiliary processing unit, a FPGA, or the like.

The method <NUM> may include assigning <NUM> a first protocol stack of a device (e.g., remote unit <NUM>) to network communications. In certain embodiments, the method <NUM> includes assigning <NUM> a second protocol stack of the device to sidelink communications. In various embodiments, the method <NUM> includes generating <NUM>, at the second protocol stack, first information based on arrival of data in a sidelink logical channel. In some embodiments, the method <NUM> includes transmitting <NUM> the first information from the second protocol stack to a network device (e.g., network unit <NUM>) via the first protocol stack.

In various embodiments, the method <NUM> further comprises determining that an application is to use the sidelink communications in a non-serving radio access technology, and, in response to determining that the application is to use the sidelink communications in the non-serving radio access technology, the second protocol stack of the device is assigned to the sidelink communications. In some embodiments, determining that the application is to use the sidelink communications comprises determining that the application is to use the sidelink communications based on an indication from an upper layer of the application. In certain embodiments, assigning the second protocol stack of the device to sidelink communications comprises activating the second protocol stack.

In one embodiment, the second protocol stack comprises a physical layer, a medium access control layer, a radio link control layer, a packet data convergence protocol layer, or some combination thereof. In various embodiments, the first protocol stack corresponds to a serving radio access technology and the second protocol stack corresponds to a non-serving radio access technology. In some embodiments, the first information comprises information indicating triggering of a buffer status report.

In certain embodiments, a medium access control layer of the second protocol stack comprises the information indicating the triggering of the buffer status report. In one embodiment, transmitting the first information from the second protocol stack to the network device via the first protocol stack comprises transmitting the first information from the medium access control layer of the second protocol stack to a medium access control layer of the first protocol stack. In various embodiments, the first information comprises an indication that data is available for transmission, a buffer occupancy, a sidelink buffer status report, or some combination thereof.

In some embodiments, in response to the first information comprising the indication that data is available for transmission, the buffer occupancy, or a combination thereof, the first protocol stack prepares a combined buffer status report based on the first information and buffer status report information corresponding to the first protocol stack. In certain embodiments, in response to the first information comprising the sidelink buffer status report, the first protocol stack transmits the sidelink buffer status report to the network device. In one embodiment, the first protocol stack transmits a buffer status report corresponding to the first protocol stack, data, or a combination thereof with the sidelink buffer status report.

In various embodiments, the first information comprises an indication of whether the buffer occupancy corresponds to sideline communications using new radio technology, sidelink communications using long-term evolution technology, uplink data, or some combination thereof. In some embodiments, the indication comprises a first medium access control control element indicating that the buffer occupancy corresponds to sideline communications using new radio technology, a second medium access control control element indicating that the buffer occupancy corresponds to sidelink communications using long-term evolution technology, a third medium access control control element indicating that buffer occupancy corresponds to uplink data, or some combination thereof.

In certain embodiments, the indication comprises a first logical channel group identifier indicating that the buffer occupancy corresponds to sideline communications using new radio technology, a second logical channel group identifier indicating that the buffer occupancy corresponds to sidelink communications using long-term evolution technology, a third logical channel group identifier indicating that buffer occupancy corresponds to uplink data, or some combination thereof.

In one embodiment, the indication comprises a first medium access control control element indicating that the buffer occupancy corresponds to sideline communications using new radio technology, a second medium access control control element indicating that the buffer occupancy corresponds to sidelink communications using long-term evolution technology, a third medium access control control element indicating that buffer occupancy corresponds to uplink data, a first logical channel group identifier indicating that the buffer occupancy corresponds to sideline communications using new radio technology, a second logical channel group identifier indicating that the buffer occupancy corresponds to sidelink communications using long-term evolution technology, a third logical channel group identifier indicating that buffer occupancy corresponds to uplink data, or some combination thereof.

In various embodiments, the method <NUM> further comprises receiving an uplink grant, and, in response to receiving the uplink grant, transmitting the first information from the second protocol stack to the network device via the first protocol stack. In some embodiments, the method <NUM> further comprises prioritizing buffer occupancies of the sidelink buffer status report in response to the uplink grant being insufficient to accommodate the buffer occupancies. In certain embodiments, the method <NUM> further comprises comparing a new radio buffer occupancy to a long-term evolution buffer occupancy using a mapping table.

In one embodiment, the method <NUM> further comprises transmitting a scheduling request if an uplink grant is unavailable and if the scheduling request is configured for at least one logical channel belonging to the second protocol stack. In various embodiments, the method <NUM> further comprises, in response to a scheduling request not being configured for the second protocol stack, initiating, via the first protocol stack, a random access procedure. In some embodiments, the random access procedure is initiated by the first protocol stack for the second protocol stack.

In certain embodiments, the method <NUM> further comprises: receiving, at the first protocol stack, second information from a network device; and transmitting the second information from the first protocol stack to the second protocol stack. In one embodiment, the second information comprises a sidelink grant indicated by a radio network temporary identifier, downlink control information, or a combination thereof.

In one embodiment, a method comprises: assigning a first protocol stack of a device to network communications; assigning a second protocol stack of the device to sidelink communications; generating, at the second protocol stack, first information based on arrival of data in a sidelink logical channel; and transmitting the first information from the second protocol stack to a network device via the first protocol stack.

In various embodiments, the method further comprises determining that an application is to use the sidelink communications in a non-serving radio access technology, and, in response to determining that the application is to use the sidelink communications in the non-serving radio access technology, the second protocol stack of the device is assigned to the sidelink communications.

In some embodiments, determining that the application is to use the sidelink communications comprises determining that the application is to use the sidelink communications based on an indication from an upper layer of the application.

In certain embodiments, assigning the second protocol stack of the device to sidelink communications comprises activating the second protocol stack.

In one embodiment, the second protocol stack comprises a physical layer, a medium access control layer, a radio link control layer, a packet data convergence protocol layer, or some combination thereof.

In various embodiments, the first protocol stack corresponds to a serving radio access technology and the second protocol stack corresponds to a non-serving radio access technology.

In some embodiments, the first information comprises information indicating triggering of a buffer status report.

In certain embodiments, a medium access control layer of the second protocol stack comprises the information indicating the triggering of the buffer status report.

In one embodiment, transmitting the first information from the second protocol stack to the network device via the first protocol stack comprises transmitting the first information from the medium access control layer of the second protocol stack to a medium access control layer of the first protocol stack.

In various embodiments, the first information comprises an indication that data is available for transmission, a buffer occupancy, a sidelink buffer status report, or some combination thereof.

In some embodiments, in response to the first information comprising the indication that data is available for transmission, the buffer occupancy, or a combination thereof, the first protocol stack prepares a combined buffer status report based on the first information and buffer status report information corresponding to the first protocol stack.

In certain embodiments, in response to the first information comprising the sidelink buffer status report, the first protocol stack transmits the sidelink buffer status report to the network device.

In one embodiment, the first protocol stack transmits a buffer status report corresponding to the first protocol stack, data, or a combination thereof with the sidelink buffer status report.

In various embodiments, the first information comprises an indication of whether the buffer occupancy corresponds to sideline communications using new radio technology, sidelink communications using long-term evolution technology, uplink data, or some combination thereof.

In some embodiments, the indication comprises a first medium access control control element indicating that the buffer occupancy corresponds to sideline communications using new radio technology, a second medium access control control element indicating that the buffer occupancy corresponds to sidelink communications using long-term evolution technology, a third medium access control control element indicating that buffer occupancy corresponds to uplink data, or some combination thereof.

In various embodiments, the method further comprises receiving an uplink grant, and, in response to receiving the uplink grant, transmitting the first information from the second protocol stack to the network device via the first protocol stack.

In some embodiments, the method further comprises prioritizing buffer occupancies of the sidelink buffer status report in response to the uplink grant being insufficient to accommodate the buffer occupancies.

In certain embodiments, the method further comprises comparing a new radio buffer occupancy to a long-term evolution buffer occupancy using a mapping table.

In one embodiment, the method further comprises transmitting a scheduling request if an uplink grant is unavailable and if the scheduling request is configured for at least one logical channel belonging to the second protocol stack.

In various embodiments, the method further comprises, in response to a scheduling request not being configured for the second protocol stack, initiating, via the first protocol stack, a random access procedure.

In some embodiments, the random access procedure is initiated by the first protocol stack for the second protocol stack.

In certain embodiments, the method further comprises: receiving, at the first protocol stack, second information from a network device; and transmitting the second information from the first protocol stack to the second protocol stack.

In one embodiment, the second information comprises a sidelink grant indicated by a radio network temporary identifier, downlink control information, or a combination thereof.

In one embodiment, an apparatus comprises: a processor that: assigns a first protocol stack of the apparatus to network communications; assigns a second protocol stack of the apparatus to sidelink communications; and generates, at the second protocol stack, first information based on arrival of data in a sidelink logical channel; and a transmitter that transmits the first information from the second protocol stack to a network device via the first protocol stack.

In various embodiments, the processor determines that an application is to use the sidelink communications in a non-serving radio access technology, and, in response to determining that the application is to use the sidelink communications in the non-serving radio access technology, the processor assigns the second protocol stack of the apparatus to the sidelink communications.

In some embodiments, the processor determines that the application is to use the sidelink communications by determining that the application is to use the sidelink communications based on an indication from an upper layer of the application.

In certain embodiments, the processor assigning the second protocol stack of the apparatus to sidelink communications comprises the processor activating the second protocol stack.

In one embodiment, the transmitter transmitting the first information from the second protocol stack to the network device via the first protocol stack comprises the processor transmitting the first information from the medium access control layer of the second protocol stack to a medium access control layer of the first protocol stack.

In various embodiments, the apparatus further comprises a receiver that receives an uplink grant, and, in response to receiving the uplink grant, the transmitter transmits the first information from the second protocol stack to the network device via the first protocol stack.

In some embodiments, the processor prioritizes buffer occupancies of the sidelink buffer status report in response to the uplink grant being insufficient to accommodate the buffer occupancies.

In certain embodiments, the processor compares a new radio buffer occupancy to a long-term evolution buffer occupancy using a mapping table.

In one embodiment, the transmitter transmits a scheduling request if an uplink grant is unavailable and if the scheduling request is configured for at least one logical channel belonging to the second protocol stack.

In various embodiments, the processor, in response to a scheduling request not being configured for the second protocol stack, initiates, via the first protocol stack, a random access procedure.

In certain embodiments, the apparatus further comprises a receiver, wherein: the receiver receives, at the first protocol stack, second information from a network device; and the transmitter transmits the second information from the first protocol stack to the second protocol stack.

Claim 1:
A method (<NUM>) comprising:
assigning (<NUM>) a first protocol stack of a device to network communications;
assigning (<NUM>) a second protocol stack of the device to sidelink communications;
generating (<NUM>), at the second protocol stack, first information based on arrival of data in a sidelink logical channel;
transmitting (<NUM>) the first information from the second protocol stack to a network device via the first protocol stack;
receiving, at the first protocol stack, second information from the network device; and
transmitting the second information from the first protocol stack to the second protocol stack,
wherein the second information comprises a sidelink grant indicated by a radio network temporary identifier, downlink control information, or a combination thereof; and
wherein the first protocol stack conveys the sidelink grant directly to a medium access control layer of the second protocol stack.