13.1.16 Emergency call setup from E-UTRAN RRC_IDLE / CS fallback to UTRAN with handover

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

13.1.16.1 Test Purpose (TP)

(1)

with { UE is in E-UTRA RRC_IDLE state }

ensure that {
when { the user initiates an emergency call }

then { UE transmits an RRCConnectionRequest message with establishmentCause set to "emergency" and an EXTENDED SERVICE REQUEST message with Service type IE set to "mobile originating CS fallback emergency call or 1xCS fallback emergency call" }

}

(2)

with { UE in E-UTRA RRC_CONNECTED state having requested an emergency call }

ensure that {
when { UE receives a MobilityFromEUTRACommand message including a cs-FallbackIndicator set to ‘true‘ and a targetRAT-Type set to ‘utra‘ }

then { UE transmits a HANDOVER TO UTRAN COMPLETE message and establishes the emergency call }

}

13.1.16.2 Conformance requirements

References: The conformance requirements covered in the present TC are specified in: TS 23.272, clause 4.6 and TS 36.331, clause 5.4.3.3.

[TS 23.272, clause 4.6]

When UE is performing CS fallback procedure for Mobile Originating Call for the purpose of emergency call, it shall indicate to the MME that this CS fallback request is for emergency purpose. MME also indicates to the E-UTRAN via the appropriate S1-AP message that this CS fallback procedure is for emergency purpose.

NOTE: E-UTRAN may use the emergency indication for selecting a particular radio access network (2G or 3G) for CS emergency handling.

[TS 36.331, clause 5.4.3.3]

The UE shall be able to receive a MobilityFromEUTRACommand message and perform a cell change order to GERAN, even if no prior UE measurements have been performed on the target cell.

The UE shall:

1> stop timer T310, if running;

1> if the MobilityFromEUTRACommand message includes the purpose set to ‘handover‘:

2> if the targetRAT-Type is set to ‘utra‘ or ‘geran‘:

3> consider inter-RAT mobility as initiated towards the RAT indicated by the targetRAT-Type included in the MobilityFromEUTRACommand message;

3> forward the nas-SecurityParamFromEUTRA to the upper layers;

3> access the target cell indicated in the inter-RAT message in accordance with the specifications of the target RAT;

3> if the targetRAT-Type is set to ‘geran‘:

4> use the contents of systemInformation, if provided for PS Handover, as the system information to begin access on the target GERAN cell;

NOTE 1: If there are DRBs for which no radio bearers are established in the target RAT as indicated in the targetRAT-MessageContainer in the message, the E-UTRA RRC part of the UE does not indicate the release of the concerned DRBs to the upper layers. Upper layers may derive which bearers are not established from information received from the AS of the target RAT.

13.1.16.3 Test description

13.1.16.3.1 Pre-test conditions

System Simulator:

– Cell 1 and Cell 5.

– System information combination 4 as defined in TS 36.508 [18] clause 4.4.3.1 is used in E-UTRA cell.

Table 13.1.16.3.1-1 shows the cell power levels after the preamble.

Table 13.1.16.3.1-1: Time instances of cell power level and parameter changes

Parameter name

Unit

Cell 1

Cell 5

T0

RS EPRE

dBm/15kHz

-85

CPICH_Ec

dBm/3.84 MHz

-70

P-CCPCH

dBm/1.28 MHz

-72

T1

RS EPRE

dBm/15kHz

Non-suitable “Off”

CPICH_Ec

dBm/3.84 MHz

-70

P-CCPCH

dBm/1.28 MHz

-72

UE:

None.

Preamble:

– The UE is in state Registered, Idle mode (state 2) on Cell 1 according to [18].

– The UE has a valid TMSI (TMSI-1) and is registered in LAI-1.

13.1.16.3.2 Test procedure sequence

Table 13.1.16.3.2-1: Main behaviour

St

Procedure

Message Sequence

TP

Verdict

U – S

Message

1

Cause the UE to originate emergency call. (see Note 1)

–

–

–

–

2

Check: Does the UE transmit an RRCConnectionRequest message on Cell 1?

–>

RRCConnectionRequest

1

P

3

The SS transmits an RRCConnectionSetup message on Cell 1.

<–

RRCConnectionSetup

–

–

4

Check: Does the UE transmit an RRCConnectionSetupComplete message on Cell 1 including an EXTENDED SERVICE REQUEST message with Service type IE set to "mobile originating CS fallback emergency call or 1xCS fallback emergency call"?

–>

RRCConnectionSetupComplete

1

P

5

The SS transmits a SecurityModeCommand message on Cell 1.

<–

SecurityModeCommand

–

–

6

The UE transmits a SecurityModeComplete message on Cell 1.

–>

SecurityModeComplete

–

–

7

The SS transmits an RRCConnectionReconfiguration message on Cell 1.

<–

RRCConnectionReconfiguration

–

–

8

The UE transmits an RRCConnectionReconfigurationComplete message on Cell 1.

–>

RRCConnectionReconfigurationComplete

–

–

8A

The SS transmits a UECapabilityEnquiry message to request UE radio access capability information for E-UTRA and UTRA.

<–

UECapabilityEnquiry

–

–

8B

The UE transmits a UECapabilityInformation message on Cell 1.

NOTE: The start-PS values received, should be used to configure ciphering on cell 5.

–>

UECapabilityInformation

–

–

9

The SS transmits a MobilityFromEUTRACommand message on Cell 1.

<–

MobilityFromEUTRACommand

–

–

10

Check: Does the test result of CALL generic procedure [18] clause 6.4.3.7.7 indicate that the UE performs CS fallback to UTRAN with Handover / emergency call on Cell 5?

–

–

2

–

11

SS adjusts cell levels according to row T1 of table 13.1.16.3.1-1.

Note 1: The trigger in step 1 is the same as in the generic procedure in 36.508 clause 6.4.3.5.

13.1.16.3.3 Specific message contents

Table 13.1.16.3.3-1: RRCConnectionRequest (step 2, Table 13.1.16.3.2-1)

Derivation Path: 36.508, Table 4.6.1-16

Information Element

Value/remark

Comment

Condition

RRCConnectionRequest ::= SEQUENCE {

criticalExtensions CHOICE {

rrcConnectionRequest-r8 SEQUENCE {

establishmentCause

emergency

}

}

}

Table 13.1.16.3.3-2: EXTENDED SERVICE REQUEST (step 4, Table 13.1.16.3.2-1)

Derivation Path: TS 36.508, Table 4.7.2-14A

Information Element

Value/remark

Comment

Condition

Service type

‘0010’B

mobile originating CS fallback emergency call or 1xCS fallback emergency call

CSFB response

Not present

Table13.1.16.3.3-3: RRCConnectionReconfiguration (step 7, Table 13.1.16.3.2-1)

Derivation Path: 36.508 Table 4.6.1-8, condition SRB2-DRB(1, 0)

Table 13.1.16.3.3-4: MobilityFromEUTRACommand (step 9, Table 13.1.16.3.2-1)

Derivation Path: 36.508, Table 4.6.1-6

Information Element

Value/remark

Comment

Condition

MobilityFromEUTRACommand ::= SEQUENCE {

criticalExtensions CHOICE {

c1 CHOICE{

mobilityFromEUTRACommand-r8 SEQUENCE {

cs-FallbackIndicator

true

purpose CHOICE{

handover SEQUENCE {

targetRAT-Type

utra

targetRAT-MessageContainer

HANDOVER TO UTRAN COMMAND(UTRA RRC message)

nas-SecurityParamFromEUTRA

The 4 least significant bits of the NAS downlink COUNT value

systemInformation

Not present

}

}

}

}

}

}

Table 13.1.16.3.3-5: HANDOVER TO UTRAN COMMAND (Table 13.1.16.3.3-4)

Derivation Path: 36.508, Table 4.7B.1-1, condition UTRA PS RB

Table 13.1.16.3.3-6: UECapabilityEnquiry (step 8A, Table 13.1.16.3.2-1)

Derivation path: 36.508 clause 4.6.1 table 4.6.1-22

Information Element

Value/Remark

Comment

Condition

UECapabilityEnquiry ::= SEQUENCE {

criticalExtensions CHOICE {

c1 CHOICE {

ueCapabilityEnquiry-r8 SEQUENCE {

ue-CapabilityRequest SEQUENCE (SIZE (1..maxRAT-Capabilities)) OF SEQUENCE {

2 entry

RAT-Type[1]

eutra

RAT-Type[2]

utra

}

}

}

}

}

Table 13.1.16.3.3-7: ATTACH ACCEPT (Preamble)

Derivation Path: 36.508 Table 4.7.2-1

Information Element

Value/remark

Comment

Condition

EPS network feature support

Not present