5.3.4 UE functionality when test loop is closed

38.5093GPP5GSRelease 17Special conformance testing functions for User Equipment (UE)TS

Tools: ARFCN - Frequency Conversion for 5G NR/LTE/UMTS/GSM

5.3.4.1 UE test loop mode A operation

UE test loop mode A provides loopback of PDCP SDUs for bi-directional data radio bearers while UE is operating in NR. The downlink PDCP SDUs received by the UE on each bi-directional data radio bearer are returned on the same radio bearer regardless of the PDCP SDU contents and of the QoS flow descriptions of the associated QoS Flow as specified in TS 24.501 [21].

Figures 5.3.4.1-1 and 5.3.4.1-2 show functional block diagrams of UE test loop function for the TMC entity and UE test loop mode A for the case when EN-DC or NGEN-DC with a MCG bearer and a SCG bearer is configured and for the case EN-DC or NGEN-DC with a MCG and a split bearer is configured.

Figures 5.3.4.1-3 shows functional block diagrams of UE test loop function for the TMC entity and UE test loop mode A for the case when standalone NR is configured Header compression / decompression block in NR PDCP covers ROCH and EHC protocols as described in TS 38.323 [19] clause 4.2.2.

Figures 5.3.4.1-4 and 5.3.4.1-5 show functional block diagrams of UE test loop function for the TMC entity and UE test loop mode A for the case when NE-DC with a MCG bearer and a SCG bearer is configured and for the case NE-DC with a MCG and a split bearer is configured.

NOTE 1: The number and the order of RB LB Entities in the functional block diagrams are provided for illustration only. No specific order or numbering is precluded.

Figure 5.3.4.1-1: Model for Test Mode Control and UE Test Loop Mode A on UE side when EN-DC or NGEN-DC with MCG bearer and SCG bearer is configured

Figure 5.3.4.1-2: Model for Test Mode Control and UE Test Loop Mode A on UE side when EN-DC or NGEN-DC with MCG and split bearer configured

Figure 5.3.4.1-3: Model for Test Mode Control and UE Test Loop Mode A on UE side when standalone NR is configured

Figure 5.3.4.1-4: Model for Test Mode Control and UE Test Loop Mode A on UE side when NE-DC with MCG and SCG bearers configured

Figure 5.3.4.1-5: Model for Test Mode Control and UE Test Loop Mode A on UE side when NE-DC with MCG and split bearers configured

UE test loop mode A is mandatory to all 5GS UEs.

Prior to closing the UE test loop mode A, thereby requesting the UE to start looping back the received data packets, at least one 5GS test mode bi-directional data radio bearer shall have been established between SS and UE. This implies that before the procedure for establishing the bi-directional data radio bearer takes place the SS needs to activate the UE test mode as specified in subclause 5.2.2.

The 5GS UE test loop mode A operation is the same as the one described in TS 36.509 [6], subclause 5.4.3 with the exception where E-UTRA is mentioned the same applies for NR, and, the understanding that the NB-IoT mode is out of the scope of the present specification.

5.3.4.2 UE test loop mode B operation

5.3.4.2.1 General

UE test loop mode B is mandatory to all 5GS UEs supporting one or more PDU session establishments.

5.3.4.2.2 UE test loop mode B operation for EN-DC and NGEN-DC

UE test loop mode B provides loopback of PDCP SDUs for bi-directional EPS bearers while UE is operated in NR or E-UTRA modes. When operating in NR or E-UTRA, the downlink PDCP SDUs or SNDCP PDUs received by the UE on all bi-directional data radio bearers are returned by the UE on the data radio bearer associated with an QoS Flow with a QoS flow descriptions matching the TCP/UDP/IP protocol information within the PDCP SDU or SNDCP SDU as specified in TS 24.501 [21].

NOTE 1: When multiple PDN connections are established (or multiple Primary PDP Contexts are active), it is assumed that different IP addresses are allocated to the UE by the SS on each PDN.

Figures 5.3.4.2.2-1 and 5.3.4.2.2-2 show functional block diagrams of UE test loop function for the TMC entity and UE test loop mode B for the case when EN-DC or NGEN-DC with a MCG bearer and a SCG bearer is configured and for the case EN-DC or NGEN-DC with a MCG and a split bearer is configured.

NOTE 2: The number and the order of RB LB Entities in the UE Test Loop Function in the functional block diagrams are provided for illustration only. No specific order or numbering is precluded.

Figure 5.3.4.2.2-1: Model for Test Mode Control and UE Test Loop Mode B on UE side when EN-DC or NGEN-DC with MCG bearer and SCG bearer is configured

Figure 5.3.4.2.2-2: Model for Test Mode Control and UE Test Loop Mode B on UE side when EN-DC or NGEN-DC with MCG and split bearer configured

5.3.4.2.3 UE test loop mode B operation for Standalone NR

UE test loop mode B provides loopback of SDAP SDUs for bi-directional QoS Flows while UE is operated in standalone NR mode. Prior to closing the UE test loop mode B, thereby requesting the UE to start looping back the received data packets, at least one 5GS test mode bi-directional QoS Flow shall have been established between SS and UE. This implies that before the procedure for establishing the bi-directional QoS Flows takes place the SS needs to activate the UE test mode as specified in subclause 5.2.2

The downlink SDAP SDUs or IP PDU’s received by the UE on all bi-directional QoS Flows are returned by the UE without any modification of the IP header to the UL QoS flow descriptions handling SAP for transmission in uplink.

NOTE 1: When multiple PDU sessions are established, it is assumed that different IP addresses are allocated to the UE by the SS on each PDU session.

Figure 5.3.4.2.3-1 shows functional block diagrams of UE test loop function for the TMC entity and UE test loop mode B for the case when standalone NR is configured.

NOTE 2: The number and the order of QoS Flow LB Entities in the UE Test Loop Function in the functional block diagrams are provided for illustration only. No specific order or numbering is precluded.

The 5GS UE test loop mode B operation is the same as the one described in TS 36.509 [6], subclause 5.4.4 with the exception where E-UTRA is mentioned the same applies for NR, and, where PDCP SDU is mentioned the same applies for SDAP SDU.

Figure 5.3.4.2.3-1: Model for Test Mode Control and UE Test Loop Mode B on UE side when standalone NR is configured

5.3.4.2.4 UE test loop mode B operation for NE-DC

UE test loop mode B provides loopback of SDAP SDUs for bi-directional QoS Flows while UE is operated in NR or E-UTRA modes. Prior to closing the UE test loop mode B, thereby requesting the UE to start looping back the received data packets, at least one 5GS test mode bi-directional QoS Flow shall have been established between SS and UE. This implies that before the procedure for establishing the bi-directional QoS Flows takes place the SS needs to activate the UE test mode as specified in subclause 5.2.2

NOTE 1: When multiple PDU sessions are established, it is assumed that different IP addresses are allocated to the UE by the SS on each PDU session.

Figure 5.3.4.2.4-1 and 5.3.4.2.4-2 show functional block diagrams of UE test loop function for the TMC entity and UE test loop mode B for the case when NE-DC with a MCG and a SCG bearer is configured and for the case NE-DC with a MCG and a split bearer is configured.

NOTE 2: The number and the order of QoS Flow LB Entities in the UE Test Loop Function in the functional block diagrams are provided for illustration only. No specific order or numbering is precluded.

Figure 5.3.4.2.4-1: Model for Test Mode Control and UE Test Loop Mode B on UE side when NE-DC with MCG bearer and SCG bearers configured

Figure 5.3.4.2.4-2: Model for Test Mode Control and UE Test Loop Mode B on UE side when NE-DC with MCG bearer and split bearers configured

5.3.4.2A UE test loop mode C operation

5.3.4.2A.1 General

UE test loop mode C is mandatory for NR UEs supporting MBS.

UE test loop mode C provides counting of successfully received MBS Packets on one MRB (Multicast MRB or Broadcast MRB) while UE is operating in NR/5GC.

– For Multicast MRB configuration:

– Multicast MRB with DL only RLC-UM or bidirectional RLC-UM configuration for PTP transmission;

– Multicast MRB with RLC-AM entity configuration for PTP transmission;

– Multicast MRB with DL only RLC-UM entity for PTM transmission;

– Multicast MRB with two RLC-UM entities, one DL only RLC-UM entity for PTP transmission and the other DL only RLC-UM entity for PTM transmission;

– Multicast MRB with three RLC-UM entities, one DL RLC-UM entity and one UL RLC-UM entity for PTP transmission and the other DL only RLC-UM entity for PTM transmission;

– Multicast MRB with two RLC entities, one RLC-AM entity for PTP transmission and the other DL only RLC-UM entity for PTM transmission.

– For Broadcast MRB configuration:

– Broadcast MRB with one DL only RLC-UM entity for PTM transmission.

Figure 5.3.4.2A.1-1 shows a functional block diagram of UE test loop function for TC entity and UE test loop mode C for Multicast MRB. The MBMS Packet Counter function is configured to count successfully received MBS packets on one Multicast MRB configured by the SS when UE test loop mode C is activated.

Figure 5.3.4.2A.1-2 shows a functional block diagram of UE test loop function for TC entity and UE test loop mode C for Broadcast MRB. The MBMS Packet Counter function is configured to count successfully received MBS packets on one Broadcast MRB configured by the SS when UE test loop mode C is activated.

Figure 5.3.4.2A.1-1: Model for UE test loop mode C on UE side for Multicast MRB

Figure 5.3.4.2A.1-2: Model for UE test loop mode C on UE side for Broadcast MRB

5.3.4.2A.2 Reception of MBS packets

For Broadcast MRB, upon receiving a MBS packet on the Broadcast MRB with Identity of the logical channel of broadcast MTCH configured in CLOSE UE TEST LOOP when operating in RRC_IDLE or RRC_CONNECTED or RRC_INACTIVE mode with UE test loop mode C active the UE shall:

1> if UE test loop mode C is active;

2> increment MBMS_PACKET_COUNTER by 1:

1> else:

2> the UE behaviour is unspecified.

For Multicast MRB, upon receiving a MBS packet on the Multicast MRB with MRB Identity configured in CLOSE UE TEST LOOP when operating in RRC_CONNECTED mode with UE test loop mode C active the UE shall:

1> if UE test loop mode C is active;

2> increment MBMS_PACKET_COUNTER by 1:

1> else:

2> the UE behaviour is unspecified.

5.3.4.2A.3 Release of RRC connection

When the RRC connection is released then the UE shall:

1> if UE test loop mode C is active for Broadcast MRB:

2> keep UE test loop mode C active.

1> else

2> the UE behaviour is unspecified.

5.3.4.3 UE test loop mode E operation

5.3.4.3.0 General

UE test loop mode E is mandatory to all 5GS UEs supporting NR sidelink.

UE test loop mode E provides means for either transmit or receive of SDAP SDUs for PC5 QoS Flows while UE is operating in NR sidelink, as specified by the test loop mode E setup IE in the CLOSE UE TEST LOOP message.

For communication receive operation, UE test loop mode E provides counting of successfully received STCH PDCP SDUs, PSCCH PHY transport blocks and PSSCH PHY transport blocks while the UE is operating in NR sidelink communication mode.

For communication transmit operation, UE test loop mode E provides trigger for transmission of NR sidelink communication packets. For the V2X out-of-coverage scenarios this trigger utilises AT commands and requires an appropriate physical interface.

Figure 5.3.4.3.0-1 shows functional block diagrams of UE test loop function for the TMC entity and UE test loop mode E for the intra-frequency or inter-frequency concurrent operation case when Communication receive is indicated in UE test loop mode E setup IE.

Figure 5.3.4.3.0-2 shows functional block diagrams of UE test loop function for the TMC entity and UE test loop mode E for the PC5-only operation case when Communication receive is indicated in UE test loop mode E setup IE.

Figure 5.3.4.3.0-3 shows functional block diagrams of UE test loop function for the TMC entity and UE test loop mode E for the intra-frequency or inter-frequency concurrent operation case when Communication transmit is indicated in UE test loop mode E setup IE.

Figure 5.3.4.3.0-4 shows functional block diagrams of UE test loop function for the TMC entity and UE test loop mode E for the PC5-only operation case when Communication transmit is indicated in UE test loop mode E setup IE.

Figure 5.3.4.3.0-1: Model for Test Mode Control and UE Test Loop Mode E on UE side when UE is in intra-frequency or inter-frequency concurrent operation (Communication receive is indicated in UE test loop mode E setup IE)

Figure 5.3.4.3.0-2: Model for Test Mode Control and UE Test Loop Mode E on UE side when UE is in PC5-only operation (Communication receive is indicated in UE test loop mode E setup IE)

Figure 5.3.4.3.0-3: Model for Test Mode Control and UE Test Loop Mode E on UE side when UE is in intra-frequency or inter-frequency concurrent operation (Communication transmit is indicated in UE test loop mode E setup IE)

Figure 5.3.4.3.0-4: Model for Test Mode Control and UE Test Loop Mode E on UE side when UE is in PC5-only operation (when Communication transmit is indicated in UE test loop mode E setup IE)

The 5GS UE test loop mode E operation is the same as the one described in TS 36.509 [6], subclause 5.4.4c with the exceptions:

– where V2X is mentioned the same applies for NR sidelink.

– Subclause 5.4.4c.1 in TS 36.509 [6] is replaced by 5.3.4.3.1 in current specification.

5.3.4.3.1 Receive or Transmit NR sidelink Communication

When operating in NR idle or connected or any cell selection state or out-of-coverage state for NR sidelink test scenarios, with UE test loop mode E active, the UE shall be able to either receive or transmit NR sidelink communication packets based on the TEST_LOOP_MODE_E_TRIGGER being set as either RECEIVE or TRANSMIT, respectively. The UE shall:

1> if TEST_LOOP_MODE_E_ACTIVE is set to TRUE:

2> if TEST_LOOP_MODE_E_TRIGGER is set to RECEIVE;

3> upon successful reception of a SDAP SDU for NR sidelink communication data packet:

4> set MATCH to zero;

4> if PROSE_COMMUNICATION_MONITOR_N > 0

5> for SL_ID = 0…(PROSE_COMMUNICATION_MONITOR_N-1):

6> if Destination Layer-2 ID corresponding to the SDAP SDU equals PROSE_COMMUNICATION_DEST_ID(SL_ID):

7> increment STCH_PACKET_COUNTER(SL_ID) by 1;

7> set MATCH to one.

4> if MATCH equal zero:

5> increment STCH_PACKET_COUNTER(PROSE_COMMUNICATION_MONITOR_N) by 1.

3> upon successful reception of a PSCCH PHY transport block for NR sidelink communication control packet:

4> increment PSCCH_PACKET_COUNTER(PROSE_COMMUNICATION_MONITOR_N) by 1.

3> upon successful reception of a PSSCH PHY transport block for NR sidelink communication data packet:

4> set MATCH to zero;

4> for SL_ID = 0…(PROSE_COMMUNICATION_MONITOR_N-1):

5> if, in the received PSSCH PHY transport block, Destination Layer-2 ID for NR sidelink communication equals PROSE_COMMUNICATION_DEST_ID(SL_ID):

6> increment PSSCH_PACKET_COUNTER(SL_ID) by 1;

6> set MATCH to one.

4> if MATCH equal zero:

5> increment PSSCH_PACKET_COUNTER (PROSE_COMMUNICATION_MONITOR_N) by 1.

2> else if TEST_LOOP_MODE_E_TRIGGER is set to TRANSMIT;

3> consider that a request from upper layers to transmit the packet for V2X service over PC5 has been received.

4> use ’00 00 00 01’H as the V2X service identifier provided by upper layer as specified in TS 24.587 [26] subclause 8.4.3.

4> use ’00 00 01 00’H as the application layer ID provided by upper layer as specified in TS 24.587 [26] subclause 8.4.4, if needed.

4> create the SDAP SDU with payload size and contents as specified below, see Figure 5.3.4.3.1-1 and Table 5.3.4.3.1-1, consider the SDAP SDU as the packet corresponding to the V2X service identifier above, and provide it as the input of PQF handling depiced in Figure 5.3.4.3.0-3 or Figure 5.3.4.3.0-4 for transmission in every PSSCH duration according to subclause 5.22.1.1 of TS 38.321 [23] for NR sidelink communication.

2> else if TEST_LOOP_MODE_E_TRIGGER is set to TRANSMIT_SL_MIMO;

3> consider that a request from upper layers to transmit the packet for V2X service over PC5 has been received.

4> use ’00 00 00 01’H as the V2X service identifier provided by upper layer as specified in TS 24.587 [26] subclause 8.4.3.

4> use ’00 00 01 00’H as the application layer ID provided by upper layer as specified in TS 24.587 [26] subclause 8.4.4, if needed.

4> transmit PSSCH in SL-MIMO mode with 2-layer precoding matrix specified in TS 38.211 [25] subclause 8.3.1.4.

NOTE: The same SDAP SDU (1 packet) is transmitted (if permitted by test specific Layer 1 and Layer 2 configuration) by the UE in every PSSCH duration for NR sidelink communication during the entire duration test loop mode E is closed.

2> else:

3> the UE behaviour is unspecified.

1> else:

2> the UE behaviour is unspecified.

The SDAP SDU payload for NR sidelink communication packet when UE test loop mode E is active shall be as specified in Figure 5.3.4.3.1-1 and Table 5.3.4.3.1-1. The UE shall also transmit the corresponding SCI control information on PSCCH accordingly in the same slot on which the SDAP SDU is transmitted for NR sidelink Communication.

Figure 5.3.4.3.1-1: NR sidelink communication Transmit operation in UE test loop mode E

Table 5.3.4.3.1-1: SDAP SDU payload contents for NR sidelink communication transmit operation in UE test loop mode E

Parameter	Value
Size (N)	300 bytes
Payload	00…00