WO2017134578A1 - Réduction de latence pour des éléments de communication - Google Patents

Réduction de latence pour des éléments de communication Download PDF

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Publication number
WO2017134578A1
WO2017134578A1 PCT/IB2017/050542 IB2017050542W WO2017134578A1 WO 2017134578 A1 WO2017134578 A1 WO 2017134578A1 IB 2017050542 W IB2017050542 W IB 2017050542W WO 2017134578 A1 WO2017134578 A1 WO 2017134578A1
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Prior art keywords
data
rsu
radio access
enb
access node
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PCT/IB2017/050542
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English (en)
Inventor
Yunxi LI
Stefan WÄNSTEDT
Marco BELLESCHI
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Telefonaktiebolaget Lm Ericsson (Publ)
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Publication of WO2017134578A1 publication Critical patent/WO2017134578A1/fr

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Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W76/00—Connection management
    • H04W76/10—Connection setup
    • H04W76/14—Direct-mode setup
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W72/00—Local resource management
    • H04W72/20—Control channels or signalling for resource management
    • H04W72/21—Control channels or signalling for resource management in the uplink direction of a wireless link, i.e. towards the network
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W72/00—Local resource management
    • H04W72/20—Control channels or signalling for resource management
    • H04W72/23—Control channels or signalling for resource management in the downlink direction of a wireless link, i.e. towards a terminal
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W4/00—Services specially adapted for wireless communication networks; Facilities therefor
    • H04W4/30—Services specially adapted for particular environments, situations or purposes
    • H04W4/40—Services specially adapted for particular environments, situations or purposes for vehicles, e.g. vehicle-to-pedestrians [V2P]
    • H04W4/46—Services specially adapted for particular environments, situations or purposes for vehicles, e.g. vehicle-to-pedestrians [V2P] for vehicle-to-vehicle communication [V2V]
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W84/00—Network topologies
    • H04W84/02—Hierarchically pre-organised networks, e.g. paging networks, cellular networks, WLAN [Wireless Local Area Network] or WLL [Wireless Local Loop]
    • H04W84/04—Large scale networks; Deep hierarchical networks
    • H04W84/042—Public Land Mobile systems, e.g. cellular systems
    • H04W84/047—Public Land Mobile systems, e.g. cellular systems using dedicated repeater stations
    • 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
    • H04W88/04—Terminal devices adapted for relaying to or from another terminal or user

Definitions

  • the present invention is generally directed communication systems and, more specifically, to a system and method to reduce latency at a communication element such as a roadside unit.
  • LTE Long Term Evolution
  • D2D device-to-device
  • An application enabled by Rel-12 LTE includes device discovery, where devices are able to sense the proximity of another device and an associated application by broadcasting and detecting discovery messages that carry device and application identities.
  • Another application includes direct communication based on physical channels terminated directly between devices.
  • Direct communication between wireless devices employing out of network coverage has become a growing condition for public safety and commercial users.
  • An objective of direct communication between non-network devices is directed to public safety considerations, which may be performed outside or partially within network coverage.
  • a characteristic of such direct communication is latency in communicating or relaying messages.
  • Direct communication without employing an intervening network access point requires detection of proximity of a public safety or other user device.
  • the communication element operable with a wireless device and a radio access node.
  • the communication element is configured to provide a scheduling request to the radio access node to communicate data from the wireless device, receive an uplink grant from the radio access node, and provide a buffer status report to the radio access node.
  • the communication element is also configured to receive another uplink grant from the radio access node, receive the data from the wireless device, and forward the data to the radio access node.
  • the communication element is configured provide a scheduling request to the radio access node to communicate data from the wireless device, receive an uplink grant from the radio access node, and provide a sideiink buffer status report to the radio access node.
  • the communication element is also configured to receive a sideiink grant from the radio access node, receive the data from the wireless device, and forward the data to another wireless device.
  • FIGUREs 1 and 2 illustrate system level diagrams of embodiments of communication systems
  • FIGUREs 3 to 9 illustrate signaling diagrams of embodiments of operations of a communication system
  • FIGURE 10 illustrates a block diagram of an embodiment of a communication element.
  • a system will be described herein with respect to exemplar ⁇ ' embodiments in a specific context, namely, a wireless communication system including a process and method to reduce latency at a communication element such as a roadside unit. While the principles will be described in the environment of a cellular communication system, any environment such as a Wi-Fi or Wi ⁇ lA ⁇ communication system that may benefit from such a system and method that enables these functionalities is well within the broad scope of the present disclosure.
  • FIGURE 1 illustrated is a system level diagram of an embodiment of a communication system embodied in an LTE-based network.
  • D2D device-to-device
  • V2X vehicle-to-vehicle
  • V2I vehicle-to-infrastructure
  • V2V sen/ices may employ either a direct link (“D2D”) (e.g., communication path 120, also referred to as an ' " interface") between vehicles or an Uu link (e.g., communication path 140, also referred to as an D2D) (e.g., communication path 120, also referred to as an ' " interface") between vehicles or an Uu link (e.g., communication path 140, also referred to as an D2D" (e.g., communication path 120, also referred to as an ' " interface”) between vehicles or an Uu link (e.g., communication path 140, also referred to as an D2D" (e.g., communication path 120, also referred to as an ' " interface”) between vehicles or an Uu link (e.g., communication path 140, also referred to as an D2D) (e.g., communication path 120, also referred to as an ' " interface”) between vehicles or an Uu link (e.g., communication path 140, also referred
  • V2X communication may take advantage of a network infrastructure when available, but at least basic V2X connectivity should be possible, even in the case of lack of coverage.
  • Providing an LTE-based V2X interface may be economically ad vantageous because of the LTE economies of scale, and it may enable tighter integration between communications with the network infrastructure (V2I) and V2P and V2V communications, as compared to using a dedicated V2X technology.
  • the V2X communications may cam' both safety and non-safety information, wherein each of the applications and sen/ices may be associated with specific requirement sets (for example, in terms of latency, reliability, capacity, etc.).
  • ETSI European Telecommunications Standards institute
  • CAM co-operative awareness message
  • DENM decentralized environmental notification message
  • the CAM is intended to enable vehicles, including emergency vehicles, to notify their presence and other relevant parameters in a broadcast fashion. Such messages target other vehicles, pedestrians, and infrastructure, and are handled by their applications.
  • the CAM also serves as active assistance to safety driving for normal traffic.
  • the availability of a CAM is indicatively checked every 100 milliseconds ("ms"), yielding a maximum detection latency requirement of less than (or equal to) 100 ms for most messages.
  • the DENM is event-triggered, such as by braking, and the availability of a DENM is also checked for every 100 ms.
  • the case latency requirements for CAM and DENM may vary significantly. As an example, latency may vary from 20 ms (for pre-crash warnings) to 100 ms (for emergency stop or queue warnings), or 1000 ms (for non- safety related use cases such as traffic flow optimization, curve speed warnings, etc.).
  • the package size of the CAM and DE M varies from 1 00 to 800 plus bytes and the typical size is around 300 bytes depending on the specific V2X use case, message type (e.g., DENM is supposed to be larger than CAM) and on the security format included in the packet (i.e., full certificate or certificate digest). The message is supposed to be detected by all vehicles in proximity.
  • SAE Society of the Automotive Engineers
  • BSM basic safety message
  • DSRC dedicated short range communications
  • a roadside unit is as an entity (a communication or network element or node) that supports V2I service that can transmit to, and receive from a wireless device such as a user equipment (“UE") using a V2T application.
  • the UE supporting V2I applications sends application layer information to the RSU, and the RSU sends application layer information to a group of UEs or to a UE supporting V2I applications without necessarily propagating such information to the core network.
  • a RSU is tailored to disseminate local information in a relatively small area, for instance, traffic intersections, parking areas, etc.
  • the RSU functionalities can be implemented either in a radio access unit such as an eNB (eNB-type RSU) or in a UE (UE-type RSU). From both physical layer and layer-2 (i. e., media access control ("MAC") packet data convergence protocol ("PDCP”)) perspectives, the functionalities of an eNB-type RSU and a UE-type RSU are different.
  • An eNB-type RSU operates over a Uu interface (e.g. t communication path 140 of FIGURE 1) towards UEs and it is connected to any other legacy eNBs on the network via X2/S 1 interfaces.
  • a UE-type RSU has a sidelink via a PC5 interface (e.g.
  • V2I use cases are, for example, emergency stop warnings, queue warnings, automated parking systems, etc.
  • the vehicles report updates to the RSU, which disseminates the information in a larger area or to a specific group of interested UEs.
  • a RSU can also be used for V2V applications such as pre-crash warnings, cruise control, for extending coverage and propagate V2V information, or V2N applications in which case the RSU will propagate a V2N message to the core network and a centralized V2X server will collect data from a macro area.
  • V2V applications such as pre-crash warnings, cruise control, for extending coverage and propagate V2V information, or V2N applications in which case the RSU will propagate a V2N message to the core network and a centralized V2X server will collect data from a macro area.
  • FIGURE 2 illustrated is a system level diagram of an embodiment of a communication system embodied in an LTE-based network.
  • the communication system demonstrates an operating scenario for a UE-type RSU over a sidelink ("SL") and Uu operations towards vehicles and E-UTRAN, respectively.
  • a vehicle 210 makes a sidelink request to a UE-type RSU 220 that in turn transmits data on an uplink ("UL") to a radio access node such as a base station 230.
  • the base station 230 communicates on a downlink (“DL”) to vehicles (one of which is designated 240).
  • DL downlink
  • the proximity services also known as D2D or LTE-direct
  • the proximity sendees are designed for a scenario in which the UEs are semi-static (no-mobility support for ProSe) and few UEs are contending the sidelink. Therefore, even though V2X will target more challenging scenarios (e.g., high mobility in a highly loaded network), V2X is inherently a ty pe of proximity service. For this reason, it is natural to assume that the V2X framework will continue to be developed in 3GPP taking the proximity services as a benchmark.
  • D2D UEs share the same spectrum as the cellular system, for example, by reserving some of the cellular uplink resources for device-to- device purposes. Allocating dedicated spectrum for device-to-device purposes is a less likely alternative as spectrum is a scarce resource and (dynamic) sharing between the device-to-device services and cellular services is more flexible and provides higher spectrum efficiency.
  • a transmission mode of sending data during D2D communication may be unicast (a specific UE is the receiver), multicast (also denoted "groupcast," a group of UEs are receivers), and broadcast (all UEs are receivers).
  • D2D data can be sent from one device to another device without prior arrangement to reduce overhead and increase communication capacity, which is beneficial in emergency situations.
  • the source device transmits data to one (unicast) or more (multicast/groupcast/broadcast) devices, without first ensuring that the recipients are available and ready to receive the data.
  • Such communication may be used for one-to-one or one-to-many communication, but it is particularly effective for broadcast and group
  • the communication may be realized, for instance, via physical layer (“PHY”) unicast/multicast/groupcast/broadcast transmissions. With PHY broadcast transmissions, the transmissions may still be turned into unicast/groupcast/multicast communication at higher layers. For example, in the media access control ("MAC " ') layer, multicast or even unicast addresses may be used . Alternatively, if using broadcast on both PHY and MAC layers, multicast or unicast Internet protocol (“IP”) addresses may be used at the IP layer.
  • PHY physical layer
  • IP Internet protocol
  • SA scheduling assignment
  • SCI sidelink control information
  • the scheduling assignments are control messages used for direct scheduling of D2D communication.
  • the scheduling assignments are transmitted by the UE that intends to transmit the D2D data, and they are received by the UEs that are potentially interested in such data.
  • the scheduling assignments are transmitted on dedicated resources characterized by time and frequency, and are typically a sparse resource.
  • the scheduling assignments provide useful information that can be used by a receiver, for example, to correctly decode the D2D data transmission associated with the scheduling assignment ⁇ e.g., the resources for data transmission, the modulation/coding parameters, timing information, identities for the transmitter and/or receiver, etc.).
  • the scheduling assignments may be transmitted prior to actual data transmission, so that a receiver is able to selectively receive the data based on the content of the assignment.
  • the data transmissions organized by the scheduling assignments are often referred to as a "transmission pattern .”
  • FIGURE 3 illustrated is a signaling diagram of an embodiment of an operation of a communication system.
  • the signaling diagram between a user equipment (designated “UE”), a roadside unit (designated “RSU”) and a radio access node such as a base station (designated “eNB”) demonstrates latency that may be induced due to Uu resource allocation .
  • UE user equipment
  • RSU roadside unit
  • eNB radio access node
  • eNB base station
  • the procedure of a RSU requesting uplink resources may include sending a scheduling request ( " 'SR") and receiving a corresponding uplink (“UL”) grant, as well as sending a buffer status report (“BSR”) and receiving a corresponding UL grant. This procedure will lead to additional delay in the RSU.
  • 'SR scheduling request
  • BSR buffer status report
  • the UE is coupled over a PCS interface to the
  • the RSU that in turn, is coupled over a Uu interface to the base station.
  • the UE transmits sidelink control information ("SCI") followed by data to the RSU.
  • the RSU transmits a scheduling request (“SR") to the base station, which responds with an uplink grant.
  • SR scheduling request
  • BSR buffer status report
  • the RSU then transm its the data to the base station .
  • delays associated with communication between the UE and the RSU range between 16 and 86 milliseconds ("ms").
  • the delays include 40 ms for the scheduling assignment ("SA") period, 8 ms for the SCI period, 32 ms for the data period, 10 ms for the SR periodicity and 3 ms for the UE/base station processing.
  • SA scheduling assignment
  • the uplink block error rate may be in the range of 10 percent.
  • FIGURE 4 illustrated is a signaling diagram of an embodiment of an operation of a communication system.
  • the communication system demonstrates the latency when the RSU forwards a packet to other UEs (such as UE-2) in the surroundings rather than to the base station.
  • the signaling diagram includes a first user equipment (designated "UE-1"), a roadside unit (designated "RSU"), a base station (designated “eNB”) and a second user equipment (designated "UE-2").
  • the UE-1 transmits sidelink control information ("SCI") followed by data to the RSU.
  • the RSU transmits a scheduling request
  • SR to the base station, which responds with an uplink grant.
  • the RSU transmits a sidelink buffer status report (“SL-BSR”) to the base station, which responds in turn with a sidelink (“SL”) grant.
  • SL-BSR sidelink buffer status report
  • the RSU then transmits the data to the UE-2.
  • the delays associated with communication between the UE and the RSU range between 16 and 86 ms, and an estimation of the mean delay due to Uu resource allocation is 24.3 ms.
  • the RSU may request resources for sidelink transmi ssion before transmitting over the sidelink to the UE-2.
  • the latency may even be higher since the uplink grant provided by the base station might not be large enough to allocate a SL-BSR if the UE- 1 has also triggered a BSR (which has higher priority than SL-BSR).
  • further SR and UL grants may be needed to finally provide the SL-BSR to the base station.
  • the RSU may request resources for the Uu transmission before it receives the data from the UE.
  • the RSU can estimate when and the quantity of resources that will be needed according to information in the SCI, which is received from the UE prior to the data.
  • the RSU can also request resources for the Uu transmission before it receives an SCI from the UE, which will improve the performance at the beginning of the data period.
  • the base station can grant resources to a RSU without receiving any S /BSR, which further reduces latency. Separate SR resources can be configured to be used to provide a more suitable uplink grant by the base station.
  • the embodiments disclosed herein apply to an RSU that forwards packets received from the sidelink to base station or to any other UE (with possible modification of the pay load) regardless of the layer.
  • the forwarding operation can happen at lower layers (e.g., in packet data convergence protocol ("PDCP")), or at higher layers (e.g., IP, in which case the RSU operates as an IP router/relay), or at an application layer implying possible modifications of the original packet payload received over the PCS interface.
  • PDCP packet data convergence protocol
  • IP IP
  • multiple packets received over the PC5 interface can be bundled into a single UL/PC5 transmission over the Uu/PC5 interface.
  • the signaling diagram includes a user equipment (designated '"UE"), a roadside unit (designated “RSU”) and a radio access node such as a base station (designated “eNB”).
  • the UE transmits sidelink control information ( " 'SCI") to the RSU .
  • the RSU transmits a scheduling request ( “" SR. " ) to the base station, which responds with an uplink grant.
  • the RSU transmits a buffer status report (“BSR") to the base station, which responds in turn with an uplink grant.
  • BSR buffer status report
  • the UE then transmits data to the RSU, winch forwards the data to the base station at a time T2.
  • the RSU When the RSU receives the SCI from the UE, the UE has not requested any Uu resources for the data associated with this SCI. Thus, the RSU estimates the time ⁇ and amount of data (also referred to as "DATA AMOUNT") needed for the communication and requests the cellular uplink resources from, the base station as part of the SR and/or the BSR. The RSU estimates the time Tl and the amount of data according to the information carried by the SCI such as resource block assignment, modulation and coding scheme, etc.
  • the RSU requests the cellular uplink resources from the base station and can indicate the amount of data for the communication via a BSR.
  • the triggering mechanisms for the BSR may be modified to reduce latency. Since the UE traffic may be suffering from latency issues (due to the two hops to reach the base station), a BSR may be triggered at the reception of the SCI. Also, a D2D BSR may be triggered by the RSU if the priority of the incoming UE traffic is higher than the priority of other remote-UE packets (possibly belonging to other remote UEs) currently queued in a RSU buffer.
  • the RSU may estimate when the time T2 (at which time the RSU can send data to the base station) will occur after the time TL
  • the RSU may delay the uplink resource request until it receives a sidelink-shared channel ("SL-SCH") transmission from the UE associated with the SCI (i.e., the RSU sends the uplink resource request after the time Tl ).
  • SL-SCH sidelink-shared channel
  • the RS U may also determine the timing of transmitting a resource request as set forth below.
  • the RSU estimates a delay from sending the uplink resource request to the time when it can transmit data using granted uplink resources (also referred to as "GRANTJDELAY").
  • the GRANTJDELAY should take into account, for instance, an estimation of the time it takes to send a scheduling request (SR) until a subsequent BSR is granted by the network, as well as the time needed by the RSU to process the uplink grant (in LTE, e.g., 4 rns).
  • SR scheduling request
  • LTE Long e.g., 4 rns
  • the base station upon reception of an SR (and before reception of a BSR), the base station sends an uplink grant that is larger for the case that the UE acts as an RSU as opposed to the case of non-RSU UE. Since the base station as shown in FIGURE 5 does not know the buffer status upon reception of the SR, the first uplink grant should be sufficiently large to accommodate the BSR and also some data. Since it is expected that the RS U buffer will contain more data (both data generated by the RSU itself and by the UE), the size of the uplink grant should be larger.
  • the SR is sent before the time Tl on the basis of the GRANT DELAY estimation, but the BSR is sent after the time Tl . This provides a better BSR estimation, since from SCI the UE may not be able to learn the priorities of incoming UE traffic.
  • the base station (after sending an uplink grant) assumes that the uplink grant is valid for longer than 4 ms, and does not expect the RSU to send the uplink data on the physical uplink shared channel ("PUSCH") within 4 ms of the uplink grant reception. In this way, even if the RSU has not yet received any data from the UE, it can still consider that the uplink grant is valid for a longer time period without sending another SR.
  • PUSCH physical uplink shared channel
  • the 8 ms hybrid automatic repeat request (“HARQ”) process mechanism should be maintained.
  • the same uplink grant can be used 8 ms, 16 ms or so, later.
  • the UE may fill the up nk grant with padding bits or may just skip the grant. In both cases, it can be configurable for a certain threshold (e.g., maximum number of MAC protocol data units ("PDUs") with padding, or maximum number of skipped grants, or a timer) above which the grant has to be considered not valid.
  • PDUs maximum number of MAC protocol data units
  • the uplink grant can be a semi -persistent scheduling (“SPS") grant that applies to every "n” subframes.
  • SPS semi -persistent scheduling
  • the signaling diagram includes a first user equipment (designated “UE-1 "), a roadside unit (designated “RSU”), a radio access node such as a base station (designated “eNB”) and a second user equipment (designated “UE-2”).
  • the UE-1 transmits sidelink control information ("SCI") to the RSU.
  • the RSU transmits a scheduling request (“SR") to the base station, which responds with an uplink grant.
  • SR scheduling request
  • the RSU transmits a sidelink buffer status report (“SL-BSR”) to the base station, which responds in turn with a sidelink (“SL”) grant.
  • SL-BSR sidelink buffer status report
  • the UE- 1 then transmits data to the RSU, which forwards the data to the UE-2 at a time T2.
  • the RSU forwards the data, to other UEs over the PC5 interface rather than to the base station over the Uu interface.
  • the delays range from 16 and 86 ms for the UE to transmit the SCI and the data to the RSU.
  • the signaling diagram includes a user equipment (designated “UE”), a roadside unit (designated “RSU ”) and a radio access node such as a base station (designated “eNB”).
  • the RSU transmits a scheduling request ("SR") to the base station, which responds with a first uplink grant to accommodate a buffer status report (“BSR").
  • BSR buffer status report
  • the UE then transmits sidelink control information ("SCI") to the RSU.
  • SCI sidelink control information
  • the RSU transmits the BSR to the base station, which responds in turn with a second uplink grant.
  • the UE transmits data to the RSU, which forwards the data to the base station.
  • the delay for the above-described process can extend from 16-86 ms.
  • the RSU can send the SR to the base station to request resources without receiving any SCI/data from the UE.
  • the first uplink grant can be used for the whole duration of the SCI period until a BSR is not included in the MAC PDU. Alternatively, after receiving a certain amount of MAC PDUs with padding, the first uplink grant may no longer be valid and discarded. Additionally, the second uplink grant is also not provided. After reception of the BSR, however, the second uplink grant is sent for transmission of data. Similar rules to those described above can be used to determine the validity of such an uplink grant. Of course, the rules can be extended to the case in which the RSU forwards packets to other UEs over the PCS interface rather than to the base station over the Uu interface.
  • the signaling diagram includes a user equipment (designated ' " UE"), a roadside unit (designated ' " RSU") and a radio access node such as a base station (designated "eNB").
  • the base station provides a first uplink grant to the RSU even prior to receiving a buffer status report ("BSR") in response to sidelink control information (“SCI").
  • BSR buffer status report
  • SCI sidelink control information
  • the base station can provide the first uplink grant because the base station is aware of SCI time-frequency resources.
  • the RSU receives the SCI from the UE.
  • the RSU transmits the BSR to the base station, which responds in turn with a second uplink grant.
  • the UE then transm its data to the RSU, which forwards the data to the base station.
  • the delay for the above-described process can extend from 16-86 ms.
  • the base station grants resources to the RSU for transmission of the BSR. Similar rules to those described above can be used to determine the validity of such an uplink grant. What is described herein can be extended to the case in which the RSU fonvards packets to other UEs over the PCS rather than to the base station over the Uu interface.
  • the signaling diagram includes a user equipment (designated “UE"), a roadside unit (designated “RSU”) and a radio access node such as a base station (designated “eNB”).
  • Hie base station provides an uplink grant to the RSU before a sidelink control information (“SCI") period starts.
  • SCI sidelink control information
  • the base station therefore, preconfigures uplink resources before the SCI period starts.
  • Such preconfiguration may also contain an offset to indicate the subframe from which the preconfiguration starts applying.
  • the preconfiguration can be provided either via RRC signaling or by an uplink grant (either dynamic or SPS) on a physical downlink control channel (“PDCCH”) .
  • PDCH physical downlink control channel
  • the RSU After receiving the uplink grant, the RSU receives the SC from the UE. n response thereto, the UE then transmits data to the RSU, which forwards the data to the base station. Again, this can be extended to the case in which the RSU forwards packets to other UEs over the PCS interface rather than to the base station over the Uu interface. As illustrated in aforementioned embodiments, the delays range from 16 and 86 ms for the UE to transmit the SCI and the data to the RSU.
  • Different scheduling requests can be used for the RSU to transmit V2X data to the base station and for ordinary uplink traffic.
  • the scheduling requests may depend on characteristics of the uplink data (including V2X data) to be transmitted to the base station.
  • the base station can allocate resources based on (e.g., optimized) for the characteristics of the data. For example, the base station can allocate a separate scheduling request to the base station to be used in case the RSU needs to monitor the SCI and possibly forward data received over the PC5 interface as disclosed herein.
  • the base station Once receiving a scheduling request in a scheduling request resource, the base station provides a large enough grant for one BSR and an uplink grant for data that can be both valid longer than a specified period such as four ms.
  • the base station can also allocate separate scheduling request resources depending on the size of the data to be transmitted so that the base station can properly dimension the uplink grant to allow the RSU to include not only a BSR but also uplink data in the next uplink transmission. What is described above can be extended to the case in which the RSU forwards packets to other UEs over the PCS interface rather than to the base station over the Uu interface. For instance, different scheduling request resources can be dedicated for the sake of sideiink
  • the RSUs will experience uplink data in different patterns.
  • the UE traffic will be busy during certain time periods of the day such as 7 to 9 AM and 4 to 6 PM in weekdays.
  • the number of UEs communicating with the RSUs and resulting traffic will be much less during other time periods.
  • a base station can record historical information of uplink traffic from the SU and predict the future uplink traffic (e.g. , for the next m inute or more). If there is no or very little uplink traffic from the RSU for the next minute or more, the base station may consider that the RSU is free; otherwise, the base station may consider the RSU busy. What is described above can be extended to the case in which the RSU forwards packets to other UEs over the PCS interface rather than to the base station over the Uu interface.
  • the communication elem ent 1000 may be a communication node such as a radio access node such as a base station, roadside unit and/or a wireless device such as a user equipment.
  • the communication element 1000 includes an interface 1010, a processor 1020, a memory 1030 and an antenna 1040. These components may work together to provide the communication element 1000 functionality, such as providing wireless connections in a wireless network.
  • the wireless network may include any number of wired or wireless networks, base stations, controllers, wireless devices, relay stations, and/or any other components that may facilitate or participate in the communication of data and/or signals whether via wired or wireless connections.
  • the communication element 1000 may be coupled to or a part of a core network such as one or more Internet Protocol ('MP") networks, public switched telephone networks (“PST s”), packet data networks, optical networks, wide area networks (“WANs”), local area networks (“LANs”), wireless local area networks (“WLANs”), wired networks, wireless networks, metropolitan area networks, and other networks to enable communication between devices.
  • 'MP Internet Protocol
  • PST s public switched telephone networks
  • packet data networks optical networks
  • WANs wide area networks
  • LANs local area networks
  • WLANs wireless local area networks
  • wired networks wireless networks
  • wireless networks metropolitan area networks
  • metropolitan area networks metropolitan area networks
  • the components of the communication element 1000 are depicted as single boxes located within a single larger box. In practice, however, the communication element 1000 may include multiple different physical components that make up a single illustrated component (e.g., the interface 1010 may include terminals for coupling wires for a wired connection and a radio transceiver for a wireless connection). As another example, the communication element 1000 may be a virtual network node in which multiple different physically separate components interact to provide the functionality thereof (e.g., the processor 1020 may include three separate processors located in three separate enclosures, wherein each processor is responsible for a different function for a particular instance of the communication element 1000), Similarly, the communication element 1000 may be composed of multiple physically separate components (e.g., a NodeB component and a radio network controller
  • RNC radio access controller
  • BTS base transceiver station
  • BSC base station controller
  • the communication element 1000 may be configured to support multiple radio access technologies ("RATs").
  • RATs radio access technologies
  • the communication element 1000 may be any type of wireless endpoint, mobile station, mobile phone, wireless local loop phone, smartphone, user equipment, desktop computer, personal digital assistant ("PDA”), cell phone, tablet, laptop, Voice over Internet Protocol (“VoIP”) phone or handset.
  • PDA personal digital assistant
  • VoIP Voice over Internet Protocol
  • the processor 1020 may be a combination of one or more of a
  • microprocessor controller, microcontroller, central processing unit, digital signal processor, application specific integrated circuit, field programmable gate array, or any other suitable computing device, resource, or combination of hardware, software and/or encoded logic operable to provide, either alone or in conjunction with other base station components such as the memory 1030, the communication element 1000 functionality.
  • the processor 1 20 may execute instructions stored in the memory 1030.
  • Such functionality may include providing various wireless features discussed herein to a wireless device including any of the features or benefits disclosed herein.
  • the memory 1030 may include any form of volatile or non-volatile computer readable memory including, without limitation, persistent storage, solid state memory, remotely mounted memory, magnetic media, optical media, random access memory ('"RAM”), read-only memory (“ROM”), removable media, or any other suitable local or remote memory component.
  • the memor ' 1030 may store any suitable instructions, data or information, including software and encoded logic, utilized by the communication element 1000.
  • the memory 1030 may be used to store any calculations made by the processor ! 020 and/or any data received via the interface 1010.
  • the communication element 1000 also includes the interface 1010 which may be used in the wired or wireless communication of signaling and/or data in a communication system .
  • the interface 1010 may perform any formatting, coding, or translating that may be needed to allow the communication element 1000 to send and receive data in the communication system.
  • the interface 1010 may also include a radio transmitter and/or receiver (also referred to as a "transceiver") that may be coupled to or a part of the antenna 1040.
  • the radio transceiver may receive digital data that is to be sent out to other communication elements.
  • the radio transceiver may convert the digital data into a radio signal having the appropriate channel and bandwidth parameters.
  • the radio signal may then be transmitted via the antenna 1040 to the appropriate recipient.
  • the antenna 1040 may be any type of antenna capable of transmitting and receiving data and/or signals wireiessly.
  • the antenna 040 may include one or more ornni-directionai, sector or panel antennas operable to transmit/receive radio signals between, for example, 2 gigahertz ("GHz") and 66 GHz.
  • GHz gigahertz
  • An omni-directional antenna may be used to transmit/receive radio signals in any direction
  • a sector antenna may be used to transmit/receive radio signals from Certain aspects of the inventive concept have mainly been described above with reference to a few embodiments. However, as is readily appreciated by a person skilled in the art, embodiments other than the ones disclosed above are equally possible and within the scope of the inventive concept.
  • the present disclosure introduces a communication element (RSU) operable with a wireless device (UE) and a radio access node (eNB), and method of operating the same.
  • the communication element (RSU) includes a processor (1020), and a memory (1030) including computer program code.
  • the processor (1020), the memory (1030), and the computer program code are collectively operable to provide a scheduling request (SR) to the radio access node (eNB) to communicate data from the wireless device (UE), receive an uplink grant from the radio access node (eNB), provide a buffer status report (BSR) to the radio access node (eNB), receive another uplmk grant from the radio access node (eNB), receive the data from the wireless device (UE), and forward the data to the radio access node (eNB).
  • SR scheduling request
  • eNB radio access node
  • BSR buffer status report
  • the memory (1030) and the computer program code are further configured to, with the processor (1020) cause the communication element (RSU) to receive sideiink control information (SCI) from the wireless device (UE) prior to providing the scheduling request (SR) to the radio access node (eNB). Additionally, the memory (1030) and the computer program code are further configured to, with the processor (1020) cause the communication element (RSU) to estimate resources for the data prior to providing the scheduling request (SR) to the radio access node (eNB).
  • the resources may include an estimated amount of data (DATA__AM()UNT) and an estimated time (Tl, T2) to forward the data.
  • the estimated time (Tl, T2) to forward the data takes into account a grant delay (GRANT_DELAY) .
  • the present disclosure also discloses a radio access node (eNB) operable with a communication element (RSU) and a wireless device (UE), and method of operating the same.
  • the radio access node (eNB) includes a processor (1020), and a memory (1030) including computer program code.
  • the processor (1020), the memory (1030), and the computer program code are collectively operable to receive a scheduling request (SR) from the communication element (RSU) to communicate data from the wireless device (UE), provide an uplink grant to the communication element (RSU), receive a buffer status report (BSR.) from the communication element (RSU), provide another uplink grant to the communication element (RSU), and receive the data from the wireless device (UE) via the communication element (RSU).
  • SR scheduling request
  • BSR buffer status report
  • the memory (1030) and the computer program code are further configured to, with the processor (1020) cause the radio access node (eNB) to receive the scheduling request (SR) from the communication element (RSU) in response to side link control information (SCI) from the wireless device (UE). Additionally, the memory (1030) and the computer program code are further configured to, with the processor (1020) cause the radio access node (eNB) to receive the scheduling request (SR) from the communication element (RSU) in response to an estimate of resources for the data.
  • the resources may include an estimated amount of data (DATA_AMOUNT) and an estimated time (Tl , T2) to forward the data.
  • the estimated time (Tl , T2) to forward the data takes into account a grant delay (GRANT DELAY).
  • the present disclosure also introduces a communication element (RSU) operable with a wireless device (UE-1) and a radio access node (eNB), and method of operating the same.
  • the communication element (RSU) includes a processor ( 1020), and a memory (1030) including computer program code.
  • the processor (1020), the memory (1030), and the computer program, code are collectively operable to provide a scheduling request (SR) to the radio access node (eNB) to communicate data from the wireless device (UE-1), receive an uplink grant from the radio access node (eNB), provide a sidelink buffer status report (SL BSR) to the radio access node (eNB), receive a sidelink (SL) grant from the radio access node (eNB), receive the data from the wireless device (UE-1), and forward the data to another wireless device (UE-2).
  • SR scheduling request
  • eNB radio access node
  • SL BSR sidelink buffer status report
  • the memory (1030) and the computer program code are further configured to, with the processor (1020) cause the communication element (RSU) to receive sidelink control information (SCI) from the wireless device (UE-1) prior to providing the scheduling request (SR) to the radio access node (eNB). Additionally, the memory (1030) and the computer program code are further configured to, with the processor (1020) cause the communication element (RSU) to estimate resources for the data prior to providing the scheduling request (SR) to the radio access node (eNB).
  • the resources may include an estimated amount of data (DATA AMOUNT) and an estimated time (Tl , T2) to forward the data.
  • the estimated time (Tl, T2) to forward the data takes into account a grant delay (GRANT _DELAY).
  • the present disclosure also discloses a radio access node (eNB) operable with a communication element (RSU) and a wireless device (UE-1), and method of operating the same.
  • the radio access node (eNB) includes a processor (1020), and a memory (1030) including computer program code.
  • the processor (1020), the memory (1030), and the computer program code are collectively operable to receive a scheduling request (SR.) from the communication element (RSU) to communicate data from the wireless device (UE-1), provide an uplink grant to the communication element (RSU), receive a sidelink buffer status report (SL BSR) from the SR.
  • SR scheduling request
  • SL BSR sidelink buffer status report
  • RSU radio access communication element
  • SL sidelink
  • RSU communication element
  • the memory (1030) and the computer program code are further configured to, with the processor (1020) cause the radio access node (eNB) to receive the scheduling request (SR) from the communication element (RSU) in response to sidelink control information (SCI) from the wireless device (UE-1). Additionally, the memory (1030) and the computer program code are further configured to, with the processor (1020) cause the radio access node (eNB) to receive the scheduling request (SR.) from the communication element (RSU) in response to an estimate of resources for the data.
  • the resources may include an estimated amount of data (DATA_AMOUNT) and an estimated time (Tl, T2.) to forward the data.
  • the estimated time (Tl, T2.) to forward the data takes into account a grant delay (GRANT DELAY).
  • the exemplary embodiment provides both a method and corresponding apparatus consisting of various modules providing functionality for performing the steps of the method.
  • the modules may be implemented as hardware (embodied in one or more chips including an integrated circuit such as an application specific integrated circuit), or may be implemented as software or firmware for execution by a processor.
  • firmware or software the exemplary embodiment can be provided as a computer program product including a computer readable storage medium embodying computer program code (i. e., software or firmware) thereon for execution by the computer processor.
  • the computer readable storage medium may be non-transitory (e.g., magnetic disks; optical disks; read only memory; flash memory devices; phase-change memory) or transitory (e.g., electrical, optical, acoustical or other forms of propagated signals-such as carrier waves, infrared signals, digital signals, etc.).
  • the coupling of a processor and other components is typically through one or more busses or bridges (also termed bus controllers).
  • the storage device and signals carrying digital traffic respectively represent one or more non-transitory or transitory computer readable storage medium.
  • the storage device of a given electronic device typically stores code and/or data for execution on the set of one or more processors of that electronic device such as a controller.

Abstract

L'invention concerne un élément de communication fonctionnant avec un dispositif sans fil et un nœud d'accès radioélectrique et un procédé de fonctionnement correspondant. Dans un mode de réalisation, l'élément de communication est conçu pour fournir une demande de programmation au nœud d'accès radioélectrique pour communiquer des données en provenance du dispositif sans fil et recevoir une autorisation de liaison montante en provenance du nœud d'accès radioélectrique. L'élément de communication est également conçu pour recevoir les données en provenance du dispositif sans fil et transmettre les données à partir du dispositif sans fil.
PCT/IB2017/050542 2016-02-04 2017-02-01 Réduction de latence pour des éléments de communication WO2017134578A1 (fr)

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WO2020018952A1 (fr) * 2018-07-20 2020-01-23 Qualcomm Incorporated Techniques destinées à faciliter la coexistence de technologies d'accès radio dans des communications sans fil
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WO2021068859A1 (fr) * 2019-10-11 2021-04-15 Qualcomm Incorporated Planification conjointe de liaisons latérale et uu
CN113038414B (zh) * 2019-12-25 2023-04-07 成都鼎桥通信技术有限公司 数据传输方法及装置
CN113038414A (zh) * 2019-12-25 2021-06-25 成都鼎桥通信技术有限公司 数据传输方法及装置
US11792770B2 (en) 2020-03-20 2023-10-17 Qualcomm Incorporated Channel restrictions for relayed sidelink communications
WO2021188644A1 (fr) * 2020-03-20 2021-09-23 Qualcomm Incorporated Planification de la transmission en liaison montante d'un relais
US11882588B2 (en) 2020-03-20 2024-01-23 Qualcomm Incorporated Scheduling sidelink transmission with relay
WO2022186945A1 (fr) * 2021-03-04 2022-09-09 Qualcomm Incorporated Techniques d'association de dispositifs assistée par liaison latérale
US20220287001A1 (en) * 2021-03-04 2022-09-08 Qualcomm Incorporated Vehicular and cellular wireless device colocation using uplink communications
US11778435B2 (en) 2021-03-04 2023-10-03 Qualcomm Incorporated Sidelink assisted cellular operation optimization
US11800581B2 (en) 2021-03-04 2023-10-24 Qualcomm Incorporated Techniques for sidelink assisted device association
US11825440B2 (en) * 2021-03-04 2023-11-21 Qualcomm Incorporated Vehicular and cellular wireless device colocation using uplink communications

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