7.29 Test method for V2X Services

36.523-33GPPEvolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Packet Core (EPC)Part 3: Test suitesRelease 17TSUser Equipment (UE) conformance specification

7.29.1 Synchronisation and SBCCH transmission

In coverage and out of coverage configurations defined in clause 7.27.2.1 apply with the exception that MIB-SL is replaced by MIB-SL-V2X. In addition, the SS-UE can be configured in GNSS/UTC time synchronised mode, in which case GNSS data and the SS-UE shall be UTC time synchronised. SS-UE shall calculate the DFN and Subframe in accordance with TS 36.331[19] clause 5.10.14.

7.29.2 Sidelink data transmission/reception

UE and SS-UE are configured with the same pool(s) of resources.

When configured in transmission, the SS-UE is configured with a layer 2 identity, corresponding to the source layer 2 identity and with the UE layer 2 identity corresponding to the service destination layer 2 identity; the SS-UE shall construct the MAC packets using these identities. The SS-UEs layer 2 identity is arbitrarily set to ‘0000BB’H for SS-E1 and ‘0B00EC’H for SS-UE2.

When configured in reception, the SS-UE is configured with a layer 2 identity, corresponding to the service destination layer 2 identity; SS-UE shall send to TTCN only the PDCP data packets received with the correct destination layer 2 identities in the MAC header. The source layer 2 identity, randomly and uniquely self-selected by UE, can be any value. SS-UE can be configured to enable/disable SCI format 1 in SL-DATA-IND.

UE can be configured in Transmit mode 3 or 4:

– When UE is configured in transmission mode 3 (i.e. scheduled), the sidelink Scheduling Grant is configured in SS by TTCN over system control port. On PDCCH, the SS informs the UE under test if it is allowed to make sidelink data transmission by transmitting ‘DCI format 5A’ including ‘SCI format 1’ parameters with the CRC scrambled by SL-V-RNTI. The UE under test will transmit on PSCCH/PSSCH as specified in the received DCI format 5A and ‘SCI format 1’. Sidelink SPS grant can be activated/deactivated in SS by TTCN with SL-SPS-V-RNTI scrambling. SS shall only react on reception of SR and grant allocation configured from the TTCN. The following sidelink grant allocation is configured:

– SS is configured to maintain PUCCH Synch.

– SS is configured to send automatically a ‘configured Grant’ to the UE on every reception of a Scheduling Request, exactly 10 subframes after reception of SL-BSR:

– the Carrier Indication and SL-Index are set as per test case prose

– the default Lowest index of the subchannel allocation to the initial transmission is set to 0

– the default configured grant for PSSCH in SCI format 1 is:

– Frequency resource location of initial transmission and retransmission is set to 30 for Bandwidth 10 and 10 for Bandwidth 20.

– Time gap = 0, no retransmission is applied

– SPS configuration index and Activation/Release are provided when SL-SPS is configured

– When UE is configured in transmission mode 4 (i.e. ue-Selected), UE selects autonomously the resources on PSCCH/PSSCH.

– When specified in the test case prose, when UE retransmits data on PSSCH, SS-UE sends to TTCN all PDCP data packets received on PSSCH independently whether this is a first transmission or a retransmission on PSSCH.

The SS-UE, when triggered to transmit data, is provided with timing either ‘timing now’ or ‘SFN/Subframe’ or ‘DFN/DSubframe’. Multiple STCH packets are transmitted every 20ms. Sensing is not applied to SS-UE. SS-UE is configured with a fixed SCI format 1 grant:

Priority = ‘100’B (arbitrary value)

Resource Reservation = 0

Frequency resource location of initial transmission and retransmission is set to 20 for Bandwidth 10 and 10 for Bandwidth 20

Time gap = 0, no retransmission is applied

MCS index = 8

7.29.3 Congestion

SS-UE is configured to transmit, over PSCCH/PSSCH, QPSK modulated uncorrelated pseudo random data on all RBs on a list of specified subchannels and subframes.

The congestion configuration is provided for one frame, it is repeated continuously or for a specific number of consecutive frames. When continuous transmission is configured the SS-UE shall transmit the congestion until a Deactivate command is received.

SS-UE is previously configured in transmission mode so that the necessary timing synchronisation, power level, frequency, bandwidth and subchannels are configured. When configured in transmission mode, only the resource pool is provided with all bits of the transmission subframe bitmap set to ‘1’B.

7.29.4 UE transmission/reception over Uu

When UE is receiving V2X data over Uu, SS-UE is not configured. SS can be configured for transmission of data either with:

– SC-PTM broadcasting with sc-mcch-RepetitionPeriod-v1430 and sc-mcch-ModificationPeriod-v1430

– MBMS broadcasting with mcch-RepetitionPeriod-v1430, mcch-ModificationPeriod-v1430 and mch-SchedulingPeriod-v1430.

When UE is transmitting V2X data over Uu, SS-UE is not configured. SS can be configured with multiple UL SPS.