The present disclosure relates to sidelink communication, and more specifically relates to determining a resource availability during sidelink communication.
In LTE V2X, partial sensing is introduced for the Pedestrian-UE (P-UE) to perform sensing with reduced power consumption. The resource reservation periods may include {100, 200, 300, ..., 1000 ms}, therefore, if intending to select a resource in subframe y, the P-UE may sense the availability of subframe y at the following times: {y-100, y-200, y-300, ..., y-1000ms}.
In NR (new radio) the resource reservation periods may include {0, 1:99, 100, 200, 300, 400, 500, 600, 700, 800, 900, 1000 ms}, the short resource reservation periods ranging from 1 to 99 are further included for urgent data transmissions.
Therefore, sensing the availability of subframe y only at the times of y-100, y-200, y-300, ..., y-1000ms may not be enough to avoid resource collision with other UEs, which utilize short resource reservation periods, such as Vehicle UE (V-UE).
It is desirable to provide a solution to avoid the resource collision.
One embodiment of the present disclosure provides a method for determining a resource availability, which includes: selecting a plurality of resources from a resource selection window; determining a sensing window based on the plurality of resources selected; and determining availability of the plurality of resources based on sensing result in the sensing window.
Another embodiment of the present disclosure provides an apparatus, which includes: a non-transitory computer-readable medium having stored thereon computer-executable instructions; a receiving circuitry; a transmitting circuitry; and a processor coupled to the non-transitory computer-readable medium, the receiving circuitry and the transmitting circuitry, wherein the computer-executable instructions cause the processor to implement the method for determining a resource availability, comprising: selecting a plurality of resources from a resource selection window; determining a sensing window based on the plurality of resources selected; and determining availability of the plurality of resources based on sensing result in the sensing window.
The detailed description of the appended drawings is intended as a description of the preferred embodiments of the present invention, and is not intended to represent the only form in which the present invention may be practiced. It should be understood that the same or equivalent functions may be accomplished by different embodiments that are intended to be encompassed within the spirit and scope of the present invention.
Reference will now be made in detail to some embodiments of the present application, examples of which are illustrated in the accompanying drawings. To facilitate understanding, embodiments are provided under specific network architecture and new service scenarios, such as 3GPP 5G, 3GPP LTE Release 8 and so on. It is contemplated that along with developments of network architectures and new service scenarios, all embodiments in the present application are also applicable to similar technical problems; and moreover, the terminologies recited in the present application may change, which should not affect the principle of the present application.
UE(s) under NR V2X scenario may be referred to as V2X UE(s). A V2X UE, which transmits data according to sidelink resource(s) scheduled by a base station (BS), may be referred to as a UE for transmitting, a transmitting UE, a transmitting V2X UE, a Tx UE, a V2X Tx UE, a SL Tx UE, or the like. A V2X UE, which receives data according to sidelink resource(s) scheduled by a BS, may be referred to as a UE for receiving, a receiving UE, a receiving V2X UE, a Rx UE, a V2X Rx UE, a SL Rx UE, or the like. The V2X UEs may include Pedestrian UE, which has limited power, and also include Vehicle UE, which does not have power limit.
V2X UE(s) may include computing devices, such as desktop computers, laptop computers, personal digital assistants (PDAs), tablet computers, smart televisions (e.g., televisions connected to the Internet), set-top boxes, game consoles, security systems (including security cameras), vehicle on-board computers, network devices (e.g., routers, switches, and modems), internet of things (IoT) devices, or the like.
According to some embodiments of the present application, V2X UE(s) may include a portable wireless communication device, a smart phone, a cellular telephone, a flip phone, a device having a subscriber identity module, a personal computer, a selective call receiver, or any other device that is capable of sending and receiving communication signals on a wireless network.
According to some embodiments of the present application, V2X UE(s) includes wearable devices, such as smart watches, fitness bands, optical head-mounted displays, or the like. Moreover, V2X UE(s) may be referred to as a subscriber unit, a mobile, a mobile station, a user, a terminal, a mobile terminal, a wireless terminal, a fixed terminal, a subscriber station, a user terminal, or a device, or described using other terminology used in the art. V2X UE(s) may communicate directly with BS(s) via uplink (UL) communication signals.
A BS under NR V2X scenario may be referred to as a base unit, a base, an access point, an access terminal, a macro cell, a Node-B, an enhanced Node B (eNB), a gNB, a Home Node-B, a relay node, a device, a remote unit, or by any other terminology used in the art. A BS may be distributed over a geographic region. Generally, a BS is a part of a radio access network that may include one or more controllers communicably coupled to one or more corresponding base stations.
A BS is generally communicably coupled to one or more packet core networks (PCN), which may be coupled to other networks, like the packet data network (PDN) (e.g., the Internet) and public switched telephone networks, among other networks. These and other elements of radio access and core networks are not illustrated but are well known generally by those having ordinary skill in the art. For example, one or more BSs may be communicably coupled to a mobility management entity (MME), a serving gateway (SGW), and/or a packet data network gateway (PGW).
A BS may serve a number of V2X UEs within a serving area, for example, a cell or a cell sector via a wireless communication link. A BS may communicate directly with one or more of V2X UEs via communication signals. For example, a BS may serve V2X UEs within a macro cell.
Sidelink communication between a Tx UE and a Rx UE under NR V2X scenario includes groupcast communication, unicast communication, or broadcast communication.
Embodiments of the present application may be provided in a network architecture that adopts various service scenarios, for example but is not limited to, 3GPP 3G, long-term evolution (LTE), LTE-Advanced (LTE-A), 3GPP 4G, 3GPP 5G NR, 3GPP LTE Release 12 and onwards, etc. It is contemplated that along with the 3GPP and related communication technology development, the terminologies recited in the present application may change, which should not affect the principle of the present application.
As shown in
In addition, although UE 101-A as shown in
According to some embodiments of
Alternatively, according to some other embodiments of
Both UE 101-A and UE 101-B in the embodiments of
BS 102 as illustrated and shown in
In case M resource reservation periods of {Po, P1, ..., PM-1} of resource pool are configured,, the UE may perform sensing and measurement in subframe at the following time periods, t0 - P0, to ty-1 - P0; t0 - P1, to ty-1 - P1; ..., and t0 - PM-1, to ty-1 -PM-1, so as to check the availability of the y subframes. The P-UE may not perform sensing between two time periods and in the interval ranges from the time n to the time t0, for the sake of power saving
The value of the resource reservation periods P0, P1, ..., PM-1 might be selected from the group of 100, 200, 300, ..., and 1000 ms, and the size of partial sensing window is 1000 ms. Although the partial sensing is repeated with a period of 100 ms in this embodiment, the partial sensing may be repeated with other periods if the configured or preconfigured resource reservation periods change. The time period from n to t0 may not be sensed.
In NR the resource reservation periods are configured from the set {0, [1:99], 100, 200, 300, 400, 500, 600, 700, 800, 900, 1000} ms. Other UEs, e.g., a V-UE, might be configured with a short resource reservation period, e.g., 5 ms. If the V-UE transmits a resource reservation request in the time period between n to t0, to reserve the resource after 5 ms, the resource requested by the V-UE may overlap the y resources selected by the P-UE. If the P-UE does not perform sensing in the time period from n to t0, the P-UE does not sense this reservation. Under this circumstance, resources collision might happen.
represents the time point when the plurality of resources start,
represents the time point when the plurality of resources end, and T2 is the size of the selection window. The resource at time
may further reserve the following resources.
When resource selection is triggered in time n, the UE shall determine the set of resources to be reported to higher layers for Physical Sidelink Shared Channel (PSSCH) transmission. In the time period from n-T0 to n-Tproc,0, the UE would perform sensing. The value of
is defined in slots in Table 1 below, where µSL is the sub-carrier spacing (SCS) configuration of the sidelink bandwidth part (BWP). depending on sub-carrier spacing
The size of T1 is up to UE implementation under the condition that 0 ≤ T1 ≤
where
is defined in slots in Table 2 below, and µSL is the SCS configuration of the BWP.
The value of T2 is determined based on T2min and the remaining packet delay budget in slots, where T2min is set to the corresponding value from higher layer parameter t2min SelectionWindow for the given value of L1 priority, prioTX.
If T2min is shorter than the remaining packet delay budget (in slots) then T2 is up to UE implementation subject to T2min ≤ T2 ≤ remaining packet budget (in slots); otherwise T2 is set to the remaining packet delay budget (in slots), that is, T2 = remaining packet budget.
To sum up, the UE determines a set of resources, which are located at
in the selection window by its implementation, which is within the time interval [n+T1,n+T2]. The value of T1 and T2 are determined based on UE implementations under the conditions T1 ≤ 4 and T2min(prioTX) ≤ T2 ≤ 100, if T2min(prioTX) is provided by higher layers for prioTX, otherwise 20 ≤ T2 ≤ 100. The selected value of T2 shall fulfil the latency requirement and the total number of resources, Y shall be greater than or equal to the high layer parameter of minimum candidate resources, minNumCandidateSF.
A set of possible resource reservation period is selected from a group including the values of: 0, [1:99], 100, 200, 300, 400, 500, 600, 700, 800, 900, 1000 ms. In the sidelink control information (SCI), less than or equal to 4 bits are used to indicate a period, and an actual set of values is configured or pre-configured.
In
respectively. The UE then determine the sensing window. The sensing window includes two parts, one is the primary sensing window, which ranges from the time n - T0 to the time n - Tproc,0. T0 may be preconfigured, and the time interval Tproc,0 is the time required for the UE to process the sensed data. The other sensing window is an additional sensing window, which ranges from the time n - Tproc,0 to the time
The configured short reservation periods may be 1, 2, ..., or 99 ms. The UE may perform full sensing in the additional sensing window ranges from the time n - Tproc,0 to the time
That is, the UE senses in each resource in the additional sensing window ranges from the time n - Tproc,0 to the time
Tproc,0, so as to determine the availability of the selected resources at time
Alternatively, the UE may perform partial sensing in the additional sensing window based on the configured reservation periods. In the primary sensing window, the UE may perform full sensing, or partial sensing depending on the practical requirements.
The UE can determine whether to perform sensing in the additional sensing window based on the Y selected resources and the values of short resource reservation periods configured with the resource pool.
According to
Tproc,0), which equals to
The smallest resource reservation period should be larger than or equal to the time of the first resource in the set of selected resources minus the ending time of the additional sensing window, which is represented as:
In conclusion, when there is one resource reservation period in the resource reservation period set has a value ranges from
to
0, the UE needs to perform sensing in the additional sensing window, otherwise, the UE may not perform the sensing in the additional sensing window.
In
respectively. The UE then determine that the sensing window ranges from
to
Define
and the sensing window is defined by the range from n′ - T0 to n′ -Tproc,0.
In
compared with the sensing solution in
The higher layer may also trigger the UE to report the availability of the subset of resources at time
to higher layer for Physical Sidelink Control Channel (PSCCH) or PSSCH transmission. After receiving the trigger the UE should report the subset of resource during the time interval from n to n + Ti. In the solutions of
The UE may report the subset of resources to higher layer during the time interval from the time n′ to n′ + T1.
The actually sensing recourses are determined by the configured parameter, sl-ResourceReservePeriodList-r16, of the resource pool. There are up to 16 resource reservation periods can be configured from {0, 1:99, 100, 200, ..., 1000} ms. Assuming sl-ResourceReservePeriodList-r16 contains the values in the group of {0, P1, P2, ..., PM}. For each resource located at the time of
in the selected Y resources, the UE should perform sensing in resource at the time of
to check whether the resource at time
could be the candidate resource for the UE, wherein i = 1, .. M.
For example, for the first resource in the Y resources, which located at time
the UE perform sensing in resource at times of
Full sensing is not required in these embodiments.
In step 701, the UE selects a plurality of resources from a resource selection window, for example, in
In
The additional sensing window is determined based on the selected resources and a set of resource reservation periods of a resource pool. More specifically speaking, the starting time of the second sensing window is determined based on the trigger of resource selection, namely, based on the time n in
in
T1 - Tproc,0.
When there is no resource reservation request will be received in the additional sensing window depicted in
to
the UE shall perform sensing in the additional sensing window. The availability of the y selected resources is determined after the additional sensing window and before the plurality of resources, for example, between the time
to the time
The ending time of the sensing window is determined based on a starting time of the plurality of resources selected. For example, both the sensing windows in
In
to
The UE may further receives a set of resource reservation periods, for example, the parameter: sl-ResourceReservePeriodList-r16, and determines the availability of the plurality of resources by sensing in a plurality of time intervals, derived based on the set of resource reservation periods, when a resource reservation request may be received. For example, in
to
The method of the present disclosure can be implemented on a programmed processor. However, controllers, flowcharts, and modules may also be implemented on a general purpose or special purpose computer, a programmed microprocessor or microcontroller and peripheral integrated circuit elements, an integrated circuit, a hardware electronic or logic circuit such as a discrete element circuit, a programmable logic device, or the like. In general, any device that has a finite state machine capable of implementing the flowcharts shown in the figures may be used to implement the processing functions of the present disclosure.
While the present disclosure has been described with specific embodiments thereof, it is evident that many alternatives, modifications, and variations will be apparent to those skilled in the art. For example, various components of the embodiments may be interchanged, added, or substituted in other embodiments. Also, all of the elements shown in each figure are not necessary for operation of the disclosed embodiments. For example, one skilled in the art of the disclosed embodiments would be capable of making and using the teachings of the present disclosure by simply employing the elements of the independent claims. Accordingly, the embodiments of the present disclosure as set forth herein are intended to be illustrative, not limiting. Various changes may be made without departing from the spirit and scope of the present disclosure.
In this disclosure, relational terms such as “first,” “second,” and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. The terms “comprises,” “comprising,” or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. An element proceeded by “a,” “an,” or the like does not, without more constraints, preclude the existence of additional identical elements in the process, method, article, or apparatus that comprises the element. Also, the term “another” is defined as at least a second or more. The terms “including,” “having,” and the like, as used herein, are defined as “comprising.”
Filing Document | Filing Date | Country | Kind |
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PCT/CN2020/106250 | 7/31/2020 | WO |