Patent Application
20230081131
The present application relates to the field of wireless communication systems or networks, more specifically to a communication among user devices, UEs, using a sidelink, SL. Embodiments of the present invention concern assistance information messages, AIMs, to provide the UEs with one or more of resource allocation related assistance information, link related assistance information, distance related assistance information, geographical area related assistance information, group related assistance information, and relay related assistance information.
For data transmission a physical resource grid may be used. The physical resource grid may comprise a set of resource elements to which various physical channels and physical signals are mapped. For example, the physical channels may include the physical downlink channel, PDSCH, the physical uplink shared channel, PUSCH, and the physical sidelink shared channel, PSSCH, carrying user specific data, also referred to as downlink, uplink or sidelink payload data, the physical broadcast channel, PBCH, and the physical sidelink broadcast channel, PSBCH, carrying for example a master information block, MIB, and one or more of a system information block, SIB, one or more sidelink information blocks (SLIBs) if supported, the physical downlink control channel, PDCCH, the physical uplink control channel, PUCCH, and the physical sidelink control channels, PSSCH, carrying for example the downlink control information, DCI, the uplink control information, UCI, or the sidelink control information, SCI. The sidelink interface may also support a 2-stage SCI, which refers to a first control region containing some parts of the SCI, and, optionally, a second control region, which contains a second part of control information.
For the uplink, the physical channels may further include the physical random access channel, PRACH or RACH, used by UEs for accessing the network once a UE synchronized and obtained the MIB and SIB. The physical signals may comprise reference signals or symbols, RS, synchronization signals and the like. The resource grid may comprise a frame or radio frame having a certain duration in the time domain and having a given bandwidth in the frequency domain. The frame may have a certain number of subframes of a predefined length, e.g., 1 ms. Each subframe may include one or more slots of 12 or 14 OFDM symbols depending on the cyclic prefix, CP, length. A frame may also consist of a smaller number of OFDM symbols, e.g., when utilizing shortened transmission time intervals, sTTI, or a mini-slot/non-slot-based frame structure comprising just a few OFDM symbols.
The wireless communication system may be any single-tone or multicarrier system using frequency-division multiplexing, like the orthogonal frequency-division multiplexing, OFDM, system, the orthogonal frequency-division multiple access, OFDMA, system, or any other IFFT-based signal with or without CP, e.g., DFT-s-OFDM. Other waveforms, like non-orthogonal waveforms for multiple access, e.g., filter-bank multicarrier, FBMC, generalized frequency division multiplexing, GFDM, or universal filtered multi carrier, UFMC, may be used. The wireless communication system may operate, e.g., in accordance with the LTE-Advanced pro standard, or the 5G or NR, New Radio, standard, or the NR-U, New Radio Unlicensed, standard.
The wireless network or communication system depicted in
In mobile communication networks, for example in a network like that described above with reference to
When considering two UEs directly communicating with each other over the sidelink, both UEs may be served by the same base station so that the base station may provide sidelink resource allocation configuration or assistance for the UEs. For example, both UEs may be within the coverage area of a base station, like one of the base stations depicted in
When considering two UEs directly communicating with each other over the sidelink, e.g., using the PC5/PC3 interface, one of the UEs may also be connected with a BS, and may relay information from the BS to the other UE via the sidelink interface and vice-versa. The relaying may be performed in the same frequency band, in-band-relay, or another frequency band, out-of-band relay, may be used. In the first case, communication on the Uu and on the sidelink may be decoupled using different time slots as in time division duplex, TDD, systems.
The scheduling and/or interference management of the V2V traffic is assisted by the gNB via control signaling over the Uu interface, which is the radio interface between the base station and the UEs. In other words, the gNB provides SL resource allocation configuration or assistance for the UEs, and the gNB assigns the resources to be used for the V2V communication over the sidelink. This configuration is also referred to as a mode 1 configuration in NR V2X or as a mode 3 configuration in LTE V2X.
UEs directly communicating with each other are to a base station but the base station does not provide for the SL resource allocation configuration or assistance. Three vehicles 206, 208 and 210 are shown directly communicating with each other over a sidelink, e.g., using the PC5 interface. The scheduling and/or interference management of the V2V traffic is based on algorithms implemented between the vehicles. This configuration is also referred to as a mode 2 configuration in NR V2X or as a mode 4 configuration in LTE V2X. As mentioned above, the scenario in
Although
In a wireless communication system or network, like the one described above with reference to
In NR or 5G, in addition to the UE-to-Network relay, also a UE-to-UE relay is supported. In such a scenario, the destination 202 is another UE.
PC5 interface, and the relay UE and the other UE 202 may communicate using also the PC5 interface.
Although
In the above-described scenarios of vehicular user devices, UEs, a plurality of such user devices may form a user device group, also referred to simply as group, and the communication within the group or among the group members may be performed via the sidelink interfaces between the user devices, like the PC5 interface. For example, the above-described scenarios using vehicular user devices may be employed in the field of the transport industry in which a plurality of vehicles being equipped with vehicular user devices may be grouped together, for example, by a remote driving application. Other use cases in which a plurality of user devices may be grouped together for a sidelink communication among each other include, for example, factory automation and electrical power distribution. In the case of factory automation, a plurality of mobile or stationary machines within a factory may be equipped with user devices and grouped together for a sidelink communication, for example for controlling the operation of the machine, like a motion control of a robot. In the case of electrical power distribution, entities within the power distribution grid may be equipped with respective user devices which, within a certain area of the system may be grouped together so as to communicate via a sidelink communication with each other so as to allow for monitoring the system and for dealing with power distribution grid failures and outages.
Naturally, in the above-mentioned use cases, sidelink communication is not limited to a communication within a group. Rather, the sidelink communication may be among any of UEs, like any pair of UEs.
Starting from the known technology as described above, there may be a need for enhancements or improvements for a sidelink communication by a UE, like an out-of-coverage UE.
An embodiment may have a user device, UE, for a wireless communication system, the wireless communication system including a plurality of user devices, UEs, wherein the UE is to communicate with one or more further UEs using a sidelink interface, SL, like a PC5 interface, wherein the UE is to send to the further UE one or more reports or assistance information messages, AIMs, to provide the further UE with one or more of the following:
Another embodiment may have a user device, UE, for a wireless communication system, the wireless communication system including a plurality of user devices, UEs, wherein the UE is to communicate with one or more further UEs using a sidelink, SL, and wherein the UE is to receive from another UE one or more reports or assistance information messages, AIMs, providing the UE with one or more of the following:
According to another embodiment, a wireless communication system may have a plurality of inventive user devices, UEs, as mentioned above and configured for a sidelink communication using, for example resources from a set of sidelink resources of the wireless communication system.
According to another embodiment, a method for operating a user device, UE, of a wireless communication system including a plurality of user devices, UEs, may have the steps of: operating the UE to communicate with one or more further UEs using a sidelink interface, SL, like a PC5 interface, and sending, by the UE, to the further UE one or more reports or assistance information messages, AIMs, to provide the further UE with one or more of the following:
According to still another embodiment, a method for operating a user device, UE, of a wireless communication system including a plurality of user devices, UEs, may have the steps of: operating the UE to communicate with one or more further UEs using a sidelink, SL, and receiving, at the UE, from another UE one or more reports or assistance information messages, AIMs, providing the UE with one or more of the following:
Another embodiment may have a non-transitory digital storage medium having stored thereon a computer program for performing a method for operating a user device, UE, of a wireless communication system including a plurality of user devices, UEs, having the steps of: operating the UE to communicate with one or more further UEs using a sidelink interface, SL, like a PC5 interface, and sending, by the UE, to the further UE one or more reports or assistance information messages, AIMs, to provide the further UE with one or more of the following:
Embodiments of the present invention are now described in further detail with reference to the accompanying drawings, in which:
Embodiments of the present invention are now described in more detail with reference to the accompanying drawings in which the same or similar elements have the same reference signs assigned.
In the wireless communication system or network, like the one described above with reference to
The above-mentioned drawbacks in conventional approaches may not only be associated with the resource allocation for the SL transmission. For the operation over the SL, the UE may need to obtain, in addition to the resource allocation information or instead of the resource allocation information, one or more of link related assistance information, distance related assistance information, geographical area related assistance information, group related assistance information, relay related assistance information. Obtaining any of this information by the UE may solve the above-mentioned problems.
For example, with regard to the link quality information, the UE may need to obtain one or more of:
For example, with regard to the distance related assistance information, the UE may need to obtain one or more of:
For example, with regard to the geographical area related assistance information, the UE may need to obtain one or more of:
For example, with regard to the group related assistance information, the UE may need to obtain one or more of:
For example, with regard to the relay related assistance information, the UE may need to obtain one or more of:
Embodiments of the present invention address the above drawbacks in conventional approaches by employing an inter-UE coordination for addressing the challenges for out-of-coverage UEs, like UEs operating in Mode 2. The inventive approach, by means of the inter UE coordination, addresses the above-mentioned problems and in accordance with embodiments, rather than obtaining the above-mentioned information by the UE, this information is provided to the UE using one or more reports or assistance information messages, AIMs, including one or more of the following:
Thereby, the present invention overcomes the above problems. For example, the inventive approach allows the SL UE to meet predefined reliability and latency requirements, as they are found, for example, in NR. Inter-UE coordination is basically to be seen as assistance provided by a first UE to a second UE. Embodiments of the present invention may be implemented in a wireless communication system as depicted in
User Device Providing an Assistance Information Message
The present invention provides (see for example claim 1) a user device, UE, for a wireless communication system, the wireless communication system including a plurality of user devices, UEs,
wherein the UE (UE-A) is to communicate with one or more further UEs (UE-B) using a sidelink interface, SL, like a PC5 interface,
wherein the UE (UE-A) is to send to the further UE (UE-B) one or more reports or assistance information messages, AIMs, to provide the further UE (UE-B) with one or more of the following:
AIM contents=resource allocation related assistance information
In accordance with embodiments (see for example claim 2), the resource allocation related assistance information indicates resources to be used by the further UE, wherein the indicated resources are in the form of, e.g., one or more of the following:
In accordance with embodiments (see for example claim 3),
In accordance with embodiments (see for example claim 4), the UE (UE-A) is to determine the set of resources by sensing, e.g., in case the UE is out-of-coverage or operating in Mode 2, or from resources provided to the UE by a base station of the wireless communication system directly, e.g., in case the UE is in Mode 1 or in-coverage, or indirectly via a relay, e.g., in case the UE is in Mode 2 or in- or out-of-coverage.
In accordance with embodiments (see for example claim 5), the further UE (UE-B) is one or more of
In accordance with embodiments (see for example claim 6), the AIM includes resources to be used by the further UE (UE-B) for a transmission to one or more other further UEs (UE-C), the other further UE (UE-C) being different from the UE (UE-A).
In accordance with embodiments (see for example claim 7),
In accordance with embodiments (see for example claim 8), the plurality of resource pools includes any combination of one or more of the following resource pools:
In accordance with embodiments (see for example claim 9),
In accordance with embodiments (see for example claim 10), to categorize the available resources, the UE is to
In accordance with embodiments (see for example claim 11), the AIM indicates a resource set to be used by the further UE in any one of the following manners:
In accordance with embodiments (see for example claim 12),
In accordance with embodiments (see for example claim 13), the link related assistance information includes one or more of the following:
In accordance with embodiments (see for example claim 14), the distance related assistance information includes one or more of the following:
In accordance with embodiments (see for example claim 15), the geographical area related assistance information includes one or more of the following:
geographical information, e.g., GPS coordinates,
In accordance with embodiments (see for example claim 16), the group related assistance information includes one or more of:
In accordance with embodiments (see for example claim 17), the UE is a part of one or more groups of UEs, the group including one or more of the further UEs.
AIM Contents=Relay Related Assistance Information
In accordance with embodiments (see for example claim 18), the relay related assistance information includes one or more of:
Aspects Independent of AIM Contents
In accordance with embodiments (see for example claim 19), the UE is to send or transmit the one or more AIMs in one or more of the following methods:
In accordance with embodiments (see for example claim 20), when transmitting the one or more AIMs as a part of a control message, the UE is to transmit a first stage SCI indicating a second stage SCI format containing the AIM to be used by the further UE (UE-B).
In accordance with embodiments (see for example claim 21), when transmitting the one or more AIMs as a part of the data transmission, the indication in the control message may be one of the following:
In accordance with embodiments (see for example claim 22),
In accordance with embodiments (see for example claim 23), when transmitting the one or more AlMs as an information block which is part of a data transmission, the UE is to transmit the one or more SLIBs as a normal data transmission with feedback enabled, wherein the further UE (UE-B) provides feedback to the UE (UE-A) depending on whether or not the SLIB was successfully received.
In accordance with embodiments (see for example claim 24), when transmitting the one of more AIMs as an information block, the resources used for the transmission of the information block, like the SLIB, are indicated in a system information block, SIB, or a master information block, MIB, wherein the further UEs (UE-B) are aware of the support of SLIBs as well as the time and frequency resources used for transmission of the SLIB from the SIB or MIB.
In accordance with embodiments (see for example claim 25), the UE is to transmit the one or more AIMs in one or more of the following methods:
In accordance with embodiments (see for example claim 26), transmitting the one or more AIMs at periodic intervals, the UE is to transmit the one or more AIMs
In accordance with embodiments (see for example claim 27), when transmitting the one or more AIMs responsive to a request by the further UE (UE-B), the UE is to
In accordance with embodiments (see for example claim 28), the UE is to receive a request from the further UE (UE-B) in one or more of the following scenarios:
In accordance with embodiments (see for example claim 29), when transmitting the one or more AIMs responsive to one or more implicit events, the UE is to automatically send an AIM to the further UE (UE-B), when a certain event occurs.
In accordance with embodiments (see for example claim 30), the certain event includes one or more of the following:
In accordance with embodiments (see for example claim 31), to detect a possibility of consecutive packet collisions, the UE is to
In accordance with embodiments (see for example claim 32), when a CBR measured for the SL resource pool hits a pre-defined threshold of occupancy, the UE (UE-A) is to send an AIM including the remaining available resources in the given resource pool.
In accordance with embodiments (see for example claim 33),
In accordance with embodiments (see for example claim 34),
The present invention provides (see for example claim 35) a user device, UE, for a wireless communication system, the wireless communication system including a plurality of user devices, UEs,
In accordance with embodiments (see for example claim 36), the AIM includes resources to be used by the UE (UE-B) for a transmission to one or more of the further UEs (UE-C), the further UE (UE-C) being different from the other UE (UE-A).
In accordance with embodiments (see for example claim 37), the UE is to request the one or more AIMs from the other UE (UE-A).
In accordance with embodiments (see for example claim 38), the UE (UE-B) is to request the one or more AIMs only when the UE requires assistance.
In accordance with embodiments (see for example claim 39), the UE requires assistance in the resource allocation procedure in one or more of the following cases:
In accordance with embodiments (see for example claim 40), responsive to receiving the one or more AIMs, the UE is not to carry out sensing for available resources in the SL resource pool.
In accordance with embodiments (see for example claim 41),
In accordance with embodiments (see for example claim 42),
In accordance with embodiments (see for example claim 43), in case an AIM expires, the UE is to trigger an AIM request message, e.g., via the SL, using a unicast communication, a groupcast communication or a broadcast responsive to which the other UE responds with the AIM.
General
In accordance with embodiments (see for example claim 44), when being out-of-coverage, the UE
In accordance with embodiments (see for example claim 45), the UE comprise one or more of a power-limited UE, or a hand-held UE, like a UE used by a pedestrian, and referred to as a Vulnerable Road User, VRU, or a Pedestrian UE, P-UE, or an on-body or hand-held UE used by public safety personnel and first responders, and referred to as Public safety UE, PS-UE, or an IoT UE, e.g., a sensor, an actuator or a UE provided in a campus network to carry out repetitive tasks and requiring input from a gateway node at periodic intervals, or a mobile terminal, or a stationary terminal, or a cellular IoT-UE, or a vehicular UE, or a vehicular group leader (GL) UE, or an IoT or narrowband IoT, NB-IoT, device, or a ground based vehicle, or an aerial vehicle, or a drone, or a moving base station, or road side unit (RSU), or a building, or any other item or device provided with network connectivity enabling the item/device to communicate using the wireless communication network, e.g., a sensor or actuator, or any other item or device provided with network connectivity enabling the item/device to communicate using a sidelink the wireless communication network, e.g., a sensor or actuator, or any sidelink capable network entity.
The present invention provides (see for example claim 46) a wireless communication system, comprising a plurality of the inventive user devices, UEs, and configured for a sidelink communication using, for example resources from a set of sidelink resources of the wireless communication system.
In accordance with embodiments (see for example claim 47), the wireless communication system comprises one or more base stations, wherein the base station comprises one or more of a macro cell base station, or a small cell base station, or a central unit of a base station, or a distributed unit of a base station, or a road side unit (RSU), or a UE, or a group leader (GL), or a relay or a remote radio head, or an AMF, or an SMF, or a core network entity, or mobile edge computing (MEC) entity, or a network slice as in the NR or 5G core context, or any transmission/reception point, TRP, enabling an item or a device to communicate using the wireless communication network, the item or device being provided with network connectivity to communicate using the wireless communication network.
Methods
The present invention provides (see for example claim 48) a method for operating a user device, UE, of a wireless communication system including a plurality of user devices, UEs, the method comprising:
The present invention provides (see for example claim 49) a method for operating a user device, UE, of a wireless communication system including a plurality of user devices, UEs, the method comprising:
Computer Program Product
Embodiments of the present invention provide a computer program product comprising instructions which, when the program is executed by a computer, causes the computer to carry out one or more methods in accordance with the present invention.
Embodiments of the inventive approach using inter-UE coordination for supporting an out-of-coverage UE are now described in more detail.
In accordance with embodiments, UE-B may be out-of-coverage, or operating in mode 1, or operating in mode 2, or connected to a relay. UE-A may be in coverage, and UE-B may be in Mode 2, in coverage or out-of-coverage, and UE-B intends to transmit on the recommended resources to UE-C that may or may not be in coverage.
For example, when UE-A is in coverage, it may obtain the resource pool from the gNB, and provide resources within this pool to other UEs. UE-A may also be provided with a specific set of resources to be forwarded to UE-B. When UE-A is out of coverage, the UE-A carries out sensing and then forwards some or all of the sensing results, like resources, to UE-B. UE-B operates in Mode 2 and receives no assistance directly from the gNB. Therefore, UE-B relies on the AIMs received from UE-A, either solely or coupled with its own sensing, to decide on resources to transmit to UE-C.
Embodiments of the present invention concern the format of the assistance report or assistance information message, AIM, the way of transmitting the AIM from the UE-A to the UE-B and the format of the message itself.
AIM Contents=Resource Allocation Related Assistance Information
In accordance with embodiments of the present invention, the assistance provided by the inter-UE coordination is in the form of a set of resources that are determined by a first UE, like UE-A, to be available and/or not available for by a second UE, like UE-B, and a corresponding report, referred to as an assistance information message, is sent to the UE-B which, in turn, uses the report to decide the transmission resources the UE-B uses for a transmission over the sidelink, e.g., to UE-C. For example, UE-A may determine from a set of sidelink resources or from a sidelink resource pool of the wireless communication system a set of resources that are available and/or unavailable for usage by UE-B, and send to UE-B one or more AIMs including the determined set of resources, so as to allow the UE-B to decide transmission resources to be used.
In accordance with embodiments the resource allocation related assistance information includes one or more of the following:
The AIM may indicate a resource set to be used by UE-B in any one of the following manners:
The AIM may indicate the resource across time in any one of the following manners:
The AIM may indicate the resource across frequency in any one of the following manners:
In accordance with embodiments, the AIM indicates the resources across time and frequency in any one of the following manners:
For example, the matrix mentioned above may include a set of vectors or may be a matrix in dense or sparse representation. The number of time slots may be variable and may be defined using a parameter that indicates a duration of the AIM.
In accordance with embodiments, UE-A may determine the set of resources that are available and/or unavailable for use by UE-B by sensing operations in the sidelink resource pool of the wireless communication system, for example, in case the UE-A is also an out-of-coverage UE, i.e., obtains no assistance from a gNB with regard to the resource allocation for a communication over the sidelink. In accordance with other embodiments, UE-A may be in-coverage and obtain the resources to be included into the AIM directly from the gNB or indirectly from the gNB via a relay, e.g., in case UE-A is in Mode 2 or in- or out-of-coverage.
In accordance with further embodiments, there may be different types of assistance information messages, AIMs, for assisting UE-B in its resource allocation, and the UE-A may transmit one or more of the AIMs to the UE-B. In accordance with embodiments, the AIMs may be based on a type of a sidelink resource pool. The AIMs in accordance with embodiments of the present invention are intended for out-of-coverage UEs, for example, for Mode 2 UEs, and a plurality of sidelink resource pools may exist. UE-A may send only an AIM including resources of one of the resource pools, or for two or more or all of the plurality of resource pools, where each AIM contains resources pertaining to a single or a plurality of resource pools.
In accordance with embodiment, the plurality of resource pools includes
In accordance with other embodiments, the AIMs may be associated with or based on priority levels. For example, when the UE-A carries out sensing, it may compare the sidelink reference signal received power, SL-RSRP, on a given resource against a predefined
RSRP threshold based on a priority of an intended transmission as well as based on the on the priority of a received transmission on the given resource. UE-A may categorize the available resources based on the priority levels that may be transmitted using the resources, and based on the categorization, different AIMs pertaining to each of the priority levels may be transmitted to the UE-B. In other words, the RSRP threshold may be selected based on two aspects, the priority of the transmission which the UE intends to transmit, and the priority of the received transmission on the said resource, which is indicated in the received SCI.
AIM Contents=Link Related Assistance Information
In accordance with embodiments of the present invention, the assistance provided by the inter-UE coordination is in the form of link related assistance information. In this type of AIM, UE-A essentially provides link information between UE-B and UE-C, which includes one or more of the following:
AIM Contents=Distance Related Assistance Information
In accordance with embodiments of the present invention, the assistance provided by the inter-UE coordination is in the form of distance related assistance information. This information is the distance between UE-B and UE-C or relative distance of UE-B and UE-C to UE-A, which UE-B may utilize for one or more of the following:
AIM Contents=Geographical Area Related Assistance Information
In accordance with embodiments of the present invention, the assistance provided by the inter-UE coordination is in the form of geographical area related assistance information. This information is typically the location of UE-C and other UEs, which may help UE-B to assess its neighboring UEs. This information includes one or more of the following:
AIM Contents=Group Related Assistance Information
In accordance with embodiments of the present invention, the UEs, like UE-A and UE-B are part of a group of UEs, and the assistance provided by the inter-UE coordination is in the form of group related assistance information. These AIMs may assist UE-B with information regarding advanced group management, the content of which includes one or more of the following:
AIM Contents=Relay Related Assistance Information
In accordance with embodiments of the present invention, the assistance provided by the inter-UE coordination is in the form of relay related assistance information. In these types of AIMs, UE-A provides information to UE-B pertaining to its functioning with the presence of a relay node, which includes one or more of the following:
Transmitting the AIM
In accordance with embodiments, various approaches for transmitting the one or more AlMs may be employed.
In accordance with a first embodiment, UE-A, which intends to assist UE-B, may transmit the one or more AIMs in accordance with a first method using a configuration message, for example, using PC5 RRC signaling or a PC5 RRC configuration message or a MAC CE. The transmission may be in a unicast, groupcast/multicast or broadcast manner.
In accordance with a second embodiment, UE-A, which intends to assist UE-B, may transmit the one or more AIMs in accordance with a second method as part of a control message, for example, as part of the sidelink control information, SCI.
In accordance with other embodiments of the second method, rather than introducing an additional second stage SCI format to be indicated in the first stage SCI for the transmission of the AIM, also existing formats may be employed.
In accordance with further embodiments, the beta_offset_indicator in an existing SCI format may be used as an indicator for additional control and/or data. For example, the beta_offset_indicator in the first stage SCI may be set to a certain value so as to indicate the presence of the AIM in the data section of the transmission. Conventionally, the beta_offset_indicator indicates the size of control data that may be found in the data region. This may include the size of the AIM. Thus, when the AIMs employed for forwarding the above mentioned information have different sizes and the presence of an AIM, e.g., as part of a second stage SCI or as additional control information in the data section, is indicated by the first stage SCI and/or second stage SCI and/or higher layer signaling, the beta_offset_indicator in a first stage SCI may be set to a certain value indicating the presence and/or size of the AIM in a second stage SCI and/or in the PSSCH.
However, when the AIMs have a fixed size and the presence of an AIM, e.g., as part of a second stage SCI or as additional control information, or an additional second stage SCI, in the data section, is indicated by the first stage and/or second stage SCI and/or higher layer signaling, the beta_offset_indicator in a first stage SCI may be set to a certain value indicating the size only of the control information other than the AIM in the PSSCH, e.g., link reports, or a second 2nd stage SCI.
In accordance with other embodiments of the second method, a first stage or second stage SCI may contain a new parameter that informs UE-B about the presence of the AIM in the corresponding data transmission.
In accordance with a third embodiment, UE-A, which intends to assist UE-B, may transmit the one or more AIMs in accordance with a third method as a part of a data transmission, which is indicated by parameters in the accompanying control message, like a SCI. The unique aspect of this embodiment is that the AIM is transmitted as an information block, and is transmitted as if it were a data transmission. For example, UE-A may transmit the one or more sidelink information blocks, SLIBs, as a normal data transmission with a feedback enabled, and UE-B provides feedback to UE-A depending on whether or not the SLIB was successfully received. Transmitting the SLIB as a normal data transmission is advantageous as the size of the second stage SCI may be kept at a minimum, and it provides UE-A with the flexibility to inform UE-B about the SLIB on an ad-hoc basis.
In accordance with a fourth embodiment, UE-A, which intends to assist UE-B, may transmit the one or more AIMs in accordance with a fourth method as an information block, e.g., in the PSSCH or the resource pool as a sidelink information block, SLIB. Thus, rather than signaling the resources to be used for the transmission of the SLIB using, for example, the SCI as explained above with reference to
Transmitting the AIM at Certain Time Instances
In accordance with embodiments of the present invention, the one or more AIMs may be transmitted at certain time instances. The UE-A may send the one or more AIMs at specific instances of time, e.g., using one of the above described approaches for transmitting the AIM.
In accordance with embodiments, UE-A may transmit the one or more AIMs at periodic intervals. For example, UE may transmit the one or more AIMs using a configuration message, like a PC5 RRC configuration message or a MAC CE, in a unicast, multicast or broadcast manner, i.e., in accordance with the above described first embodiment for transmitting the one or more AIMS. In accordance with other examples, the UE may transmit the one or more AIMs as an information block, wherein the resources used for the transmission of the information block, like a SLIB, i.e., in accordance with the above described fourth embodiment for transmitting the one or more AIMS.
In accordance with other embodiments, the UE-A may transmit the one or more AIMs based on an implicit event. Responsive to the event, UE-A may transmit the one or more AIMs aperiodically, e.g., once following the event, or UE-A may transmit the one or more AIMs periodically, like n-times for a specified time period to increase reliability, e.g., due to the half-duplex issue, and to ensure the AIM is received. In accordance with embodiments, the above-described first to third embodiments for transmitting the AIM may be employed for sending the AIMs.
An implicit event may refer to consecutive packet collisions. In case UE-A detects that there is a possibility of consecutive packet collisions for a transmission to be carried out by UE-B, UE-A may provide an AIM for this purpose. For example, UE-A may detect the potential of collisions by listening to the SCIs being transmitted by other UEs. The SCIs contain not only current resource locations of a transmission, but also resource locations for future transmissions, for example, for up to two further future transmissions. When UE-A recognizes from the SCIs that they point to the same future transmission resources that also UE-B intends to use, UE-A may provide an AIM to UE-B in order to counter this. In other words, the AIM may be created on the basis of the current resources, the future resources and the intended resources. This addresses a situation of the UE-B not being able to receive the transmissions of the SCIs from other UEs, since it transmitted its own SCI at that time and, due to the half-duplex issue, missed the other SCIs.
In accordance with other embodiments, the implicit event may be based on a channel busy ratio, CBR, threshold. The CBR may be measured for the sidelink resource pool for indicating the congestion or occupancy of the resources. In case the CBR measured hits a predefined threshold of occupancy, UE-A may send an AIM including the remaining available resources in the given resource pool. In accordance with embodiments, such an AIM may be sent only for resource pools having PSFCH enabled, as the resource pool with such high-quality resources is basically only used for high reliability transmissions.
Further examples for the implicit event may include one or more of the following:
In accordance with yet other embodiments, a time instance when the AIM is to be transmitted from the UE-A to the UE-B may be triggered by the UE-B. In other words, a transmission of the AIM may be performed on request by the UE-B. The UE-B may explicitly request the UE-A to send an AIM to assist UE-B with its resource allocation. The UE-B may request UE-A for an AIM, for example using a PC5 RRC or MAC CE signaling. Responsive to the request, UE-A may transmit the AIM to the UE-B in accordance with one of the above-described first to third embodiments for transmitting the AIM. Responsive to the request, UE-A may transmit the AIMs aperiodically, e.g., once following the request, or UE-A may transmit the AIMs periodically, like n-times for a specified time period to increase reliability.
In accordance with embodiments, UE-B may request the AIM in case it requires assistance in its resource allocation procedure. For example, such a need for assistance may arise in case of the transmission of packets that require a high reliability and/or a low latency and/or high priority. This is to ensure that the packet is received by the intended recipient at the first attempt in order to maintain the low latency requirement, and using resources that are available so as to avoid any potential resource collisions. Another situation in which the UE may require assistance is when the UE obtains inadequate or no sensing results. For example, in case UE-B was not able to obtain adequate sensing results during a handover so that it has not enough sensing results for deciding on resources to be used for the sidelink transmission, it may request an AIM from the UE-A. In accordance with other embodiments, UE-B may not have any sensing results at all, for example due to a radio link failure, RLF, or because it is operating in a DRX mode. Also, in this case, the UE-B may request from UE-A the AIM for obtaining resources for the sidelink transmission to be used by UE-B.
Further examples for UE-B to request for an AIM from UE-A may include one or more of the following:
In accordance with other embodiments of the present invention, the one or more AIMs may be provided within a group. In case of groupcast communications, UE-A, which may be a group leader UE, may assist UE-B, which is a member UE of the group formed by UE-A, UE-B and potentially other UEs, by providing one or more AIMs. Thus, the one or more member UEs, like UE-B need not carry out operations, like sensing, to obtain the information, rather the information indicated in the AIM may be used for carrying out a transmission.
In accordance with the yet further embodiments of the present invention, a UE-B, that receives the AIM, may use the information included in the AIM together with its own sensing results, for example to fine-tune its resource selection process. This approach may be used when UE-B does not see certain UEs and their allocated resources, for example due to the near-far problem. In this situation, the respective resources of the invisible UEs are indicated in the AIM received from the UE-B. In accordance with embodiments, the UE-B may prioritize resources which, by its own sensing and by the AIM received from the UE-A, are expected to be free. The AIM may also indicate resources that are not to be used by UE-B for transmission to UE-C, and UE-B may use this information from the AIM to eliminate these resources during its sensing process. This type of reservation of resources via AIM may be utilized in case resource have to be reserved for high priority services or for emergency services.
Further embodiments of the present invention relate to the AIM propagation and global consistency. In accordance with such embodiments, procedures are provided to ensure that the assistance information is consistent for a plurality of UEs. Consistency means that the parameters defined in the AIM are reliably applied for all relevant UEs in space as well as in time. For example, parameters in the one or more AIMs may change dependent on the geographical area the UE is operating in, and an AIM may be applied only within a certain geographical area. Also, the one or more AIMs may change over time so that they may be applied only during a certain time period. Also switching between parameters defined in the one or more AIMs may be required to happen for all UEs at the same time, for example, in case the parameters are not compatible.
In accordance with embodiments, an AIM may have associated therewith a geographical area within which the AIM is valid. This means that when a UE is leaving the geographical area, the AIM needs to be disabled or refreshed.
In accordance with other embodiments, the one or more AIMs may have associated therewith an activation time. This allows the AIM to be transmitted multiple times to make sure that all receiving UEs successfully receive the AIM before it is actually activated. This may be applied when the AIM changed and needs to be updated at multiple UEs.
In accordance with yet further embodiments, an AIM may expire or may be missing, in response to such a situation, the UE may trigger an AIM request message. This may be done using a unicast or multicast/groupcast communication or a broadcast communication.
General
Embodiments of the present invention have been described in detail above, and the respective embodiments and aspects may be implemented individually or two or more of the embodiments or aspects may be implemented in combination.
In accordance with embodiments, the wireless communication system may include a terrestrial network, or a non-terrestrial network, or networks or segments of networks using as a receiver an airborne vehicle or a spaceborne vehicle, or a combination thereof.
In accordance with embodiments, the user device, UE, described herein may be one or more of a power-limited UE, or a hand-held UE, like a UE used by a pedestrian, and referred to as a Vulnerable Road User, VRU, or a Pedestrian UE, P-UE, or an on-body or hand-held UE used by public safety personnel and first responders, and referred to as Public safety UE, PS-UE, or an IoT UE, e.g., a sensor, an actuator or a UE provided in a campus network to carry out repetitive tasks and requiring input from a gateway node at periodic intervals, or a mobile terminal, or a stationary terminal, or a cellular IoT-UE, or a vehicular UE, or a vehicular group leader (GL) UE, or an IoT, or a narrowband IoT, NB-loT, device, or a WiFi non Access Point STAtion, non-AP STA, e.g., 802.11ax or 802.11be, or a ground based vehicle, or an aerial vehicle, or a drone, or a moving base station, or a road side unit, or a building, or any other item or device provided with network connectivity enabling the item/device to communicate using the wireless communication network, e.g., a sensor or actuator, or any other item or device provided with network connectivity enabling the item/device to communicate using a sidelink the wireless communication network, e.g., a sensor or actuator, or any sidelink capable network entity.
The base station, BS, described herein may be implemented as mobile or immobile base station and may be one or more of a macro cell base station, or a small cell base station, or a central unit of a base station, or a distributed unit of a base station, or a road side unit, or a UE, or a group leader (GL), or a relay, or a remote radio head, or an AMF, or an SMF, or a core network entity, or mobile edge computing entity, or a network slice as in the NR or 5G core context, or a WiFi AP STA, e.g., 802.11ax or 802.11be, or any transmission/reception point, TRP, enabling an item or a device to communicate using the wireless communication network, the item or device being provided with network connectivity to communicate using the wireless communication network.
Embodiments concern the following types of UEs communicating over a sidelink PC5:
Embodiments of the inventive approach are described for sidelink communications in the context of cellular communication systems, safety communication systems, campus networks. The present invention is not limited to this, rather, in accordance with further embodiments, the inventive approach may be employed in any kind of communication network, e.g., an ad-hoc communication network.
Although some aspects of the described concept have been described in the context of an apparatus, it is clear that these aspects also represent a description of the corresponding method, where a block or a device corresponds to a method step or a feature of a method step. Analogously, aspects described in the context of a method step also represent a description of a corresponding block or item or feature of a corresponding apparatus.
Various elements and features of the present invention may be implemented in hardware using analog and/or digital circuits, in software, through the execution of instructions by one or more general purpose or special-purpose processors, or as a combination of hardware and software. For example, embodiments of the present invention may be implemented in the environment of a computer system or another processing system.
The terms “computer program medium” and “computer readable medium” are used to generally refer to tangible storage media such as removable storage units or a hard disk installed in a hard disk drive. These computer program products are means for providing software to the computer system 500. The computer programs, also referred to as computer control logic, are stored in main memory 506 and/or secondary memory 508. Computer programs may also be received via the communications interface 510. The computer program, when executed, enables the computer system 500 to implement the present invention. In particular, the computer program, when executed, enables processor 502 to implement the processes of the present invention, such as any of the methods described herein. Accordingly, such a computer program may represent a controller of the computer system 500. Where the disclosure is implemented using software, the software may be stored in a computer program product and loaded into computer system 500 using a removable storage drive, an interface, like communications interface 510.
The implementation in hardware or in software may be performed using a digital storage medium, for example cloud storage, a floppy disk, a DVD, a Blue-Ray, a CD, a ROM, a PROM, an EPROM, an EEPROM or a FLASH memory, having electronically readable control signals stored thereon, which cooperate (or are capable of cooperating) with a programmable computer system such that the respective method is performed. Therefore, the digital storage medium may be computer readable.
Some embodiments according to the invention comprise a data carrier having electronically readable control signals, which are capable of cooperating with a programmable computer system, such that one of the methods described herein is performed.
Generally, embodiments of the present invention may be implemented as a computer program product with a program code, the program code being operative for performing one of the methods when the computer program product runs on a computer. The program code may for example be stored on a machine readable carrier.
Other embodiments comprise the computer program for performing one of the methods described herein, stored on a machine readable carrier. In other words, an embodiment of the inventive method is, therefore, a computer program having a program code for performing one of the methods described herein, when the computer program runs on a computer.
A further embodiment of the inventive methods is, therefore, a data carrier (or a digital storage medium, or a computer-readable medium) comprising, recorded thereon, the computer program for performing one of the methods described herein. A further embodiment of the inventive method is, therefore, a data stream or a sequence of signals representing the computer program for performing one of the methods described herein. The data stream or the sequence of signals may for example be configured to be transferred via a data communication connection, for example via the Internet. A further embodiment comprises a processing means, for example a computer, or a programmable logic device, configured to or adapted to perform one of the methods described herein. A further embodiment comprises a computer having installed thereon the computer program for performing one of the methods described herein.
In some embodiments, a programmable logic device (for example a field programmable gate array) may be used to perform some or all of the functionalities of the methods described herein. In some embodiments, a field programmable gate array may cooperate with a microprocessor in order to perform one of the methods described herein. Generally, the methods may be performed by any hardware apparatus.
While this invention has been described in terms of several embodiments, there are alterations, permutations, and equivalents which fall within the scope of this invention. It should also be noted that there are many alternative ways of implementing the methods and compositions of the present invention. It is therefore intended that the following appended claims be interpreted as including all such alterations, permutations and equivalents as fall within the true spirit and scope of the present invention.
| Number | Date | Country | Kind |
|---|---|---|---|
| 20164706.2 | Mar 2020 | EP | regional |
This application is a continuation of copending International Application No. PCT/EP2021/056932, filed Mar. 18, 2021, which is incorporated herein by reference in its entirety, and additionally claims priority from European Application No. 20164706.2, filed Mar. 20, 2020, which is also incorporated herein by reference in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/EP2021/056932 | Mar 2021 | US |
| Child | 17947821 | US |
