24.1.19 V2X Sidelink Communication / Pre-configured authorisation / Utilisation of the pre-configured resources / CBR measurement / Transmission based on CR limit

36.523-13GPPEvolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Packet Core (EPC)Part 1: Protocol conformance specificationRelease 17TSUser Equipment (UE) conformance specification

24.1.19.1 Test Purpose (TP)

(1)

with { UE being authorized for performing V2X sidelink Communication and preconfigured with Radio parameters for when the UE is "not served by E-UTRAN" }

ensure that {

when { congestion is introduced on V2X sidelink by SS-UEs and UE has measured CBR}

then { UE utilizes subchannels for data transmission as per the CR limit for the measured CBR}

24.1.19.2 Conformance requirements

References: The conformance requirements covered in the current TC are specified in: TS 23.285, clauses 4.4.1.1.1, 4.4.1.1.2, 4.4.2, 4.5.1, 5.3

[TS 23.285, clause 4.4.1.1.1]

The basic principles of service authorization for V2X communications over PC5 reference point:

– The UE gets authorization to use V2X communications over PC5 reference point on a per PLMN basis in the serving PLMN by the V2X Control Function in the HPLMN.

– The V2X Control Function in the HPLMN requests authorization information from the V2X Control Function of the serving PLMN.

– The V2X Control Function in the HPLMN merges authorization information from home and serving PLMNs and informs the UE of the final authorization information.

– The V2X Control Function in the VPLMN or HPLMN may revoke the authorization at any time. The V2X Control Function in the HPLMN shall be notified when authorization is revoked by the VPLMN.

[TS 23.285, clause 4.4.1.1.2]

The following information is provisioned to the UE for V2X communications over PC5 reference point:

1) Authorization policy:

– When the UE is "served by E-UTRAN":

– PLMNs in which the UE is authorized to perform V2X communications over PC5 reference point.

– When the UE is "not served by E-UTRAN":

– Indicates whether the UE is authorized to perform V2X communications over PC5 reference point when "not served by E-UTRAN".

2) Radio parameters for when the UE is "not served by E-UTRAN":

– Includes the radio parameters with Geographical Area(s) and an indication of whether they are "operator managed" or "non-operator managed. These radio parameters (e.g. frequency bands) are defined in TS 36.331 [9]. The UE uses the radio parameters to perform V2X communications over PC5 reference point when "not served by E-UTRAN" only if the UE can reliably locate itself in the corresponding Geographical Area. Otherwise, the UE is not authorized to transmit.

NOTE 1: Whether a frequency band is "operator managed" or "non-operator managed" in a given Geographical Area is defined by local regulations.

3) Policy/parameters:

– The mapping of Destination Layer-2 ID(s) and the V2X services, e.g. PSID or ITS-AIDs of the V2X application.

NOTE 1: PLMN operators coordinate to make sure Destination Layer-2 ID(s) for different V2X services are configured in a consistent manner.

NOTE 2: To pre-configure a UE with the provisioning parameters, at least the "not served by E-UTRAN" parameters of 1) and 2), and the parameters of 3) need to be included.

– The mapping of ProSe Per-Packet Priority and packet delay budget for V2X communication (autonomous resources selection mode).

– The list of V2X services, e.g. PSID or ITS-AIDs of the V2X applications, with Geographical Area(s) that require privacy support.

– The mapping of service types (e.g. PSID or ITS-AIDs) to V2X frequencies (see TS 36.300 [10] for further information) with Geographical Area(s).

[TS 23.285, clause 4.4.2]

PC5 reference point as defined in TS 23.303 [5] is used for the transmission and reception of V2X messages. The V2X communication over PC5 reference point supports roaming and inter-PLMN operations. V2X communication over PC5 reference point is supported when the UE is "served by E-UTRAN" and when the UE is "not served by E‑UTRAN".

A UE is authorized to transmit and receive V2X messages by the V2X Control Function in its home PLMN as described in clause 5.2.

The V2X communication over PC5 reference point is a type of ProSe Direct Communication with the following characteristics:

– The V2X communication over PC5 reference point is connectionless, and there is no signalling over PC5 control plane for connection establishment.

– V2X messages are exchanged between UEs over PC5 user plane.

– Both IP based and non-IP based V2X messages are supported.

– For IP based V2X messages, only IPv6 is used. IPv4 is not supported in this release.

The identifiers used in the V2X communication over PC5 reference point are described in clause 4.5.1.

[TS 23.285, clause 4.5.1]

Each UE has a Layer-2 ID for the V2X communication over PC5 reference point, which is included in the source Layer-2 ID field of every frame that it sends on the layer-2 link. The UE self-assigns the Layer-2 ID for the V2X communication over PC5 reference point.

When IP based V2X messages are supported, the UE auto-configures a link local IPv6 address to be used as the source IP address, as defined in clause 4.5.3 of TS 23.303 [5].

If the UE has an active V2X application that requires privacy support in the current Geographical Area, as identified by configuration described in clause 4.4.1.1.2, in order to ensure that a source UE (e.g. vehicle) cannot be tracked or identified by any other UEs (e.g. vehicles) beyond a certain short time-period required by the application, the source Layer-2 ID must be changed over time and randomized. For IP based V2X communication over PC5 reference point, the source IP address must be also changed over time and randomized. The change of the identifiers of a source UE must be synchronized across layers used for PC5, e.g. when application layer identifier changes, the source Layer-2 ID and the source IP address need to be changed.

The UE is configured with the destination Layer-2 ID(s) to be used for V2X services. The Layer-2 ID for a V2X message is selected based on the configuration as described in clause 4.4.1.1.

[TS 23.285, clause 5.3]

To perform V2X communication over PC5 reference point, the UE is configured with the related information as described in clause 4.4.1.1.

The procedure for one-to-many ProSe Direct Communication transmission described in clause 5.4.2 of TS 23.303 [5] is applied to V2X communication over PC5 reference point with following differences:

– The source Layer-2 ID is set to the Layer-2 ID described in clause 4.5.1.

– A UE shall be configured with a set of Layer-2 ID corresponding to different type of services.

The procedure for one-to-many ProSe Direct Communication reception described in clause 5.4.3 of TS 23.303 [5] is applied to V2X communication over PC5 reference point.

[TS 36.214, clause 5.1.30]

Channel busy ratio (CBR)

Definition

Channel busy ratio (CBR) measured in subframe n is defined as follows:

– For PSSCH, the portion of sub-channels in the resource pool whose S-RSSI measured by the UE exceed a (pre-)configured threshold sensed over subframes [n-100, n-1];

– For PSCCH, in a pool (pre)configured such that PSCCH may be transmitted with its corresponding PSSCH in non-adjacent resource blocks, the portion of the resources of the PSCCH pool whose S-RSSI measured by the UE exceed a (pre-)configured threshold sensed over subframes [n-100, n-1], assuming that the PSCCH pool is composed of resources with a size of two consecutive PRB pairs in the frequency domain.

Applicable for

RRC_IDLE intra-frequency,

RRC_IDLE inter-frequency,

RRC_CONNECTED intra-frequency,

RRC_CONNECTED inter-frequency

NOTE: The subframe index is based on physical subframe index

[TS 36.214, clause 5.1.31]

Channel occupancy ratio (CR)

Definition

Channel occupancy ratio (CR) evaluated at subframe n is defined as the total number of sub-channels used for its transmissions in subframes [n-a, n-1] and granted in subframes [n, n+b] divided by the total number of configured sub-channels in the transmission pool over [n-a, n+b].

Applicable for

RRC_IDLE intra-frequency,

RRC_IDLE inter-frequency,

RRC_CONNECTED intra-frequency,

RRC_CONNECTED inter-frequency

NOTE 1: a is a positive integer and b is 0 or a positive integer; a and b are determined by UE implementation with a+b+1 = 1000, a >= 500, and n+b should not exceed the last transmission opportunity of the grant for the current transmission.

NOTE 2: CR is evaluated for each (re)transmission.

NOTE 3: In evaluating CR, the UE shall assume the transmission parameter used at subframe n is reused according to the existing grant(s) in subframes [n+1, n+b] without packet dropping.

NOTE 4: The subframe index is based on physical subframe index.

NOTE 5: CR can be computed per priority level

[TS 36.213, clause 14.1.1.4B]

If the UE has a configured sidelink grant (described in [8]) in subframe with the corresponding PSCCH resource m (described in Subclause 14.2.4), the resource blocks and subframes of the corresponding PSSCH transmissions are determined according to 14.1.1.4C.

The number of subframes in one set of the time and frequency resources for transmission opportunities of PSSCH is given by  where = 10*SL_RESOURCE_RESELECTION_COUNTER [8] if configured else is set to 1.

If a set of sub-channels in subframe  is determined as the time and frequency resource for PSSCH transmission corresponding to the configured sidelink grant (described in [8]), the same set of sub-channels in subframes  are also determined for PSSCH transmissions corresponding to the same sidelink grant where j=1, 2,…, ,  , and  is determined by Subclause 14.1.5. Here,  is the resource reservation interval indicated by higher layers.

If a UE is configured with high layer parameter cr-Limit and transmits PSSCH in subframe n, the UE shall ensure the following limits for any priority value k;

where  is the CR evaluated in subframe n-4 for the PSSCH transmissions with “Priority” field in the SCI set to i, and  corresponds to the high layer parameter cr-Limit that is associated with the priority value k and the CBR range which includes the CBR measured in subframe n-4. It is up to UE implementation how to meet the above limits, including dropping the transmissions in subframe n.

24.1.19.3 Test description

24.1.19.3.1 Pre-test conditions

System Simulator:

SS-NW

– No E-UTRA cell configured

– 1 GNSS simulator

SS-UE

– SS-UE1: Preconfigured with V2X sidelink related parameters as per TS 36.508 Table 4.10.1.1-1, the sidelink bandwidth is set to 10MHz and configured for and operating as V2X sidelink Communication receiving device.

– SS-UE2: Preconfigured with V2X sidelink related parameters as per TS 36.508 Table 4.10.1.1-1, the sidelink bandwidth is set to 10MHz and configured for and operating as V2X sidelink Communication transmitting device simulating the congestion.

– Simulation of transmission on 65 subframes (fully occupied) out of 100 subframes (100 ms) in order to achieve 65% congestion. This equals one SS-UE transmitting on 6.5 (6 full subframes utilizing all RBs on all subchannels of the transmitting TTI and one subframe with only 5 subchannels fully occupied) out of 10 consecutive subframes, according to the transmit pattern shown in Table 24.1.19.3.1-1, and repeating continuously the same transmit pattern in subsequent frames. SS-UE transmits dummy random data on all RBs on the specified subchannels implying congestion on PSCCH and PSSCH.

Table 24.1.19.3.1-1: Transmit pattern for simulation of 65% congestion

65% Congestion

Subframe 0

Subframe 1

Subframe 2

Subframe 3

Subframe 4

Subframe 5

Subframe 6

Subframe 7

Subframe 8

Subframe 9

SC1

SC1

SC1

SC1

SC1

SC1

SC1

SC1

SC1

SC1

SC2

SC2

SC2

SC2

SC2

SC2

SC2

SC2

SC2

SC2

SC3

SC3

SC3

SC3

SC3

SC3

SC3

SC3

SC3

SC3

SC4

SC4

SC4

SC4

SC4

SC4

SC4

SC4

SC4

SC4

SC5

SC5

SC5

SC5

SC5

SC5

SC5

SC5

SC5

SC5

SC6

SC6

SC6

SC6

SC6

SC6

SC6

SC6

SC6

SC6

SC7

SC7

SC7

SC7

SC7

SC7

SC7

SC7

SC7

SC7

SC8

SC8

SC8

SC8

SC8

SC8

SC8

SC8

SC8

SC8

SC9

SC9

SC9

SC9

SC9

SC9

SC9

SC9

SC9

SC9

SC10

SC10

SC10

SC10

SC10

SC10

SC10

SC10

SC10

SC10

Note: SC stands for subchannel. Each column above represents one TTI of 1ms. Bold font means blocked due to transmission.

UE:

– V2X sidelink related configuration

– Authorised to perform V2X Sidelink Communication

– The UE is equipped with below information in UE or in a USIM containing default values (as per TS 36.508) except for those listed in Table 24.1.19.3.1-1.

Table 24.1.19.3.1-1: UE/ USIM configuration

USIM field

Priority

Value

Access Technology Identifier

EFUST

Service n°119 (V2X) supported

EFVST

As per TS 36.508 [18] clause 4.9.3.4

EFV2X_CONFIG

SL-V2X-Preconfiguration field as defined in Table 24.1.19.3.3-1.

Geographical area field as defined in TS 36.508 [18] clause 4.9.3.1 and with the sidelink bandwidth set to 10 MHz

Preamble:

– The UE is in state V2X out of coverage (State 5-V2X) according to TS 36.508 [18].

– V2X sidelink communication is congestion free.

24.1.19.3.2 Test procedure sequence

Table 24.1.19.3.2-1: Main behaviour

St

Procedure

Message Sequence

TP

Verdict

U – S

Message

1

Trigger UE to activate UE test loop mode

NOTE: The activation of UE test loop mode may be performed by MMI or AT command (+CATM).

–

–

–

–

2

Void

–

–

–

–

3

Trigger the UE to reset UTC time.

NOTE: The UTC time reset may be performed by MMI or AT command (+CUTCR).

–

–

–

–

4

SS configures:

GNSS simulator is configured for Scenario #1: Scenario #1: static in Geographical area #1, and starts step 1 to simulate a location in the centre of Geographical area #1 as defined in TS 36.508 Table 4.11.1.2-2. Geographical area #1 is also pre-configured in the UE.

–

–

–

–

5

Trigger UE to transmit 919 bytes of data every 100ms on V2X sidelink communication.

(Note 1)(Note 2)

–>

STCH PDCP SDU packet

–

–

6

Wait for 1100ms to allow the UE to measure the congestion.

–

–

–

–

7

Check: Does the UE transmit data on the V2X sidelink communication utilizing 100 subchannels in 1 sec(10000 subchannels) as per the Tx parameters mentioned in clause 24.1.19.3.3?

NOTE: STCH PDCP SDU packet are received on SS-UE1

–>

STCH PDCP SDU packet

1

P

8

SS triggers UE to stop data transmission on V2X sidelink communication.

NOTE: UE may use AT command(+CV2XDTS) or MMI to stop data transmission

–

–

–

–

9

SS-UE2 is reconfigured to achieve 65% congestion continuously in consecutive timeframes according to the transmission pattern shown in Table 24.1.19.3.1-1.

–

–

–

–

10

Trigger UE to transmit 919 bytes of data every 100ms on V2X sidelink communication.

(Note 1) (Note 2)

–

–

–

–

11

Wait for 1100ms to allow the UE to measure the congestion.

–

–

–

–

12

Check: Does the UE transmit data on the V2X sidelink communication utilizing 50 subchannels in 1 sec(10000 subchannels) as per the Tx parameters mentioned in clause 24.1.19.3.3?

NOTE: STCH PDCP SDU packet are received on SS-UE1

–>

STCH PDCP SDU packet

1

P

13

SS triggers UE to stop data transmission on V2X sidelink communication.

NOTE: UE may use AT command(+CV2XDTS) or MMI to stop data transmission

–

–

–

–

14

Trigger UE to deactivate UE test loop mode.

NOTE: The deactivation of UE test loop mode may be performed by MMI or AT command (+CATM)

–

–

–

–

Note 1: 935 bytes(TBS) of data is derived by using MCS = 9 and Nprb = 48 from TS 3GPP 36.213 Table 7.1.7.1-1 and Table 7.1.7.2.1-1 which gives TBS = 7480 bits/TTI. Step 2 and Step 7 mentions 919 bytes which is excluding headers.

Note 2: UE may use AT command(+CV2XDTS) or MMI to transmit data. Although the UE is expected to transmit continuously, only this STCH PDCP SDU packet is shown explicitly in the step sequence. Reception of this packet ensures that UE has acquired GNSS.

24.1.19.3.3 Specific message contents

Table 24.1.19.3.3-1: SL-V2X-Preconfiguration

Derivation Path: 36.508 [18] Table 4.10.1.1-1

Information Element

Value/remark

Comment

Condition

SL-V2X-Preconfiguration-r14 ::= SEQUENCE {

v2x-PreconfigFreqList-r14 SEQUENCE (SIZE (1..maxFreqV2X-r14)) OF SEQUENCE {

1 entry of SL-V2X-PreconfigFreqInfo-r14(Table 24.1.19.3.3-2)

}

anchorCarrierFreqList-r14

Not present

cbr-PreconfigList-r14 SEQUENCE {

cbr-RangeCommonConfigList-r14 SEQUENCE (SIZE (1..maxSL-V2X-CBRConfig2-r14)) OF SEQUENCE {

2 entries

SL-CBR-r14

60

SL-CBR-r14

70

}

sl-CBR-PSSCH-TxConfigList-r14 SEQUENCE (SIZE (1..maxSL-V2X-TxConfig2-r14)) OF SEQUENCE {

2 entries

cr-Limit-r14

10000

tx-Parameters-r14 {

minMCS-PSSCH-r14

9

maxMCS-PSSCH-r14

9

minSubChannel-NumberPSSCH-r14

10

maxSubchannel-NumberPSSCH-r14

10

allowedRetxNumberPSSCH-r14

n0

maxTxPower-r14

Not Present

}

}

cr-Limit-r14

50

tx-Parameters-r14 {

minMCS-PSSCH-r14

9

maxMCS-PSSCH-r14

9

minSubChannel-NumberPSSCH-r14

10

maxSubchannel-NumberPSSCH-r14

10

allowedRetxNumberPSSCH-r14

n0

maxTxPower-r14

Not Present

}

}

}

}

Table 24.1.19.3.3-2: SL-V2X-PreconfigFreqInfo-r14

Derivation Path: 36.508 [18] Table 4.6.3-20K

Information Element

Value/remark

Comment

Condition

SL-V2X-PreconfigFreqInfo-r14 ::= SEQUENCE {

v2x-CommPreconfigGeneral-r14 SEQUENCE {

SL-PreconfigGeneral-r12

maxTxPower-r12

23

additionalSpectrumEmission-r12

32

A-MPR doesn’t apply by default.

See TS 36.101 table 6.2.4-1

sl-bandwidth-r12

n50

reserved-r12

‘00000000 00000000 010’B

}

v2x-CommRxPoolList-r14 SEQUENCE (SIZE (1..maxSL-V2X-RxPoolPreconf-r14)) OF SL-V2X-PreconfigCommPool-r14 {

1 entry

SL-V2X-PreconfigCommPool-r14[1]

SL-V2X-PreconfigCommPool-r14 (Table 24.1.19.3.3-3)

}

}

Table 24.1.19.3.3-3: SL-V2X-PreconfigCommPool-r14

Derivation Path: 36.508 [18] Table 4.6.3-20J

Information Element

Value/remark

Comment

Condition

SL-V2X-PreconfigCommPool-r14 ::= SEQUENCE {

sl-Subframe-r14 {

bs20-r14

11111111111111111111

BITMAP_6

}

threshS-RSSI-CBR-r14

16

}