8.5.3 MBMS Frequency Layer Convergence and Dispersion

34.123-13GPPPart 1: Protocol conformance specificationRelease 15TSUser Equipment (UE) conformance specification

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

8.5.3.1 MBMS Session Start (Frequency Layer Convergence)/Session Stop (Frequency Layer Dispersion) in Idle mode / MBMS Selected Service

8.5.3.1.1 Definition

This test is applicable for all UEs supporting MBMS broadcast services.

8.5.3.1.2 Conformance requirement

The UE shall perform the MBMS frequency layer selection procedure upon receiving the IE "MBMS Preferred frequency information" or when specified explicitly e.g. as in subclause 8.6.9.2, or when the priority for an MBMS service as indicated by upper layers changes.

The UE shall:

1> if there exist two or more preferred frequencies for services included in variable MBMS_ACTIVATED_SERVICES:

2> request from upper layers the priorities of the different MBMS services included in variable MBMS_ACTIVATED_SERVICES for which a preferred frequency has been received.

1> if the UE is in idle mode:

2> if a preferred frequency layer applies for a service included in variable MBMS_ACTIVATED_SERVICES:

3> select the preferred frequency indicated for the MBMS service(s) prioritised most by upper layers for which a preferred frequency exists as the preferred frequency.

….

1> if a preferred frequency has been selected:

2> if the UE is not in CELL_DCH state:

3> apply the cell-reselection procedure as described in [4], using the received "MBMS Preferred frequency information" applicable to the selected frequency:

4> if HCS is not used, and the IE "Qoffmbms" is not present for the MBMS preferred frequency:

5> consider the cells on the MBMS preferred frequency having a Qoffmbms equal to "infinity".

4> if HCS is used, and the IE "HCS_OFFmbms" is not present for the MBMS preferred frequency:

5> consider the cells on the MBMS preferred frequency having the highest HCS priority level.

3> if the UE re-selects to a cell on the indicated preferred frequency:

4> if the UE is in CELL_FACH, CELL_PCH or URA_PCH:

5> act according to subclause 8.3.1.2.

4> store the frequency information of the frequency on which the UE was operating prior to cell-reselection to the preferred frequency in the variable MBMS_PREV_FREQUENCY_INFORMATION.

4> apply the MCCH acquisition procedure, as specified in subclause 8.7.2.

…

If the IE "MBMS required UE action" is included and concerns an MBMS activated service the UE shall:

1> if the "MBMS required UE action" is set to ‘None’:

2> take no action with respect to this IE.

1> if the IE "MBMS required UE action" is set to ‘Acquire counting info’ or set to ‘Acquire counting info– PTM RBs unmodified’:

2> perform the MBMS counting procedure as specified in subclause 8.7.4;

NOTE: If upper layers indicate that an MBMS transmission has already been received correctly, the UE will continue as if the information about the concerned MBMS transmission was not included in the message. This implies that the UE does not respond to counting for a transmission already received correctly.

1> if the IE "MBMS required UE action" is set to ‘Acquire PTM RB info’; or

1> if the IE "MBMS required UE action" is set to ‘Acquire counting info– PTM RBs unmodified’ and the UE is not receiving a p-t-m RB for the concerned service:

2> continue acquiring the MBMS COMMON P-T-M RB INFORMATION, MBMS CURRENT CELL P-T-M RB INFORMATION and the MBMS NEIGHBOURING CELL P-T-M RB INFORMATION messages without delaying reading of MCCH until the next modification period and without stopping at the end of the modification period, in accordance with subclause 8.7.1.3

2> act upon the MBMS COMMON P-T-M RB INFORMATION, MBMS CURRENT CELL P-T-M RB INFORMATION and the MBMS NEIGHBOURING CELL P-T-M RB INFORMATION message, if received, in accordance with subclause 8.7.5;

…

1> if the IE "MBMS required UE action" is set to ‘Release PTM RB’:

2> stop receiving the concerned MBMS service;

2> if the UE is in a state other than CELL_DCH (for FDD) or if the UE is in Idle mode, URA_PCH or CELL_PCH state (for TDD); and

2> if the UE does not decide to receive an MBMS service; and

2> if the variable MBMS_PREV_FREQUENCY_INFO is not empty:

3> if any frequency in SIB11 or SIB12 has the same frequency stored in the variable MBMS_PREV_FREQUENCY_INFO:

4> select a suitable UTRA cell in that frequency.

4> if no suitable UTRA cell in that frequency is found:

5> select a suitable UTRA cell in another frequency.

3> if no frequency in SIB11 or SIB12 has the same frequency stored in the variable MBMS_PREV_FREQUENCY_INFO.

4> select a frequency randomly among the inter-frequencies indicated in SIB11 or SIB12.

5> select a suitable UTRA cell in the selected frequency

5> if no suitable UTRA cell in the selected frequency is found:

6> select a suitable UTRA cell in another frequency.

3> clear the variable MBMS_PREV_FREQUENCY_INFO.

2> clear all service specific information applicable for the concerned service.

NOTE: The UE is only required to acquire the relevant SIB11 or SIB12, according to what is specified in subclauses 8.1.1.6.11 and 8.1.1.6.12.

…

If the UE is receiving an MBMS service that is not included in variable MBMS_ACTIVATED_SERVICES and that is using a p-t-m radio bearer, the UE shall:

1> stop receiving the concerned MBMS service and clear all service specific information applicable for the concerned service.

Upon completing the reception of the MBMS MODIFIED SERVICES INFORMATION and the MBMS UNMODIFIED SERVICES INFORMATION messages, the UE shall

1> act as follows for each of the services included in these messages provided that the service is included in variable MBMS_ACTIVATED_SERVICES and upper layers indicate that the session has not yet been received correctly (referred to as ‘applicable services’);

1> act upon all received information elements as specified in subclause 8.6, unless specified otherwise in the following;

1> if one or more preferred frequency applies for the applicable services:

2> delay acting upon the "MBMS Preferred frequency information" until receiving the relevant MCCH information i.e. the MBMS GENERAL INFORMATION message;

2> act upon the "MBMS Preferred frequency information" as specified in subclause 8.6.9.4 for the service(s) that upper layers indicate to have highest priority.

1> perform MBMS frequency selection procedure as specified in subclause 8.5.27;

1> if the UE receives an MBMS service using a p-t-m radio bearer and the received messages do not contain an IE "MBMS required UE action" set to "Acquire PTM RB info" or set to "Acquire counting info– PTM RBs unmodified" for that service then the UE shall:

2> stop receiving the concerned MBMS service and clear all service specific information applicable for the concerned service.

…

The UE shall, in the transmitted RRC CONNECTION REQUEST message:

1> otherwise if the UE performs connection establishment for MBMS counting as specified in subclause 8.7.4; and

1> if one or more of the MBMS services for which the UE initiates the counting response concerns an MBMS Selected Service:

2> for each MBMS Selected Service that is indicated on MCCH and for which the UE initiates the counting response:

3> order the MBMS Selected Services such that those selected with a higher priority are listed in the IE "MBMS Selected Services Short" before those selected with a lower priority;

3> include the IE "MBMS Selected Service ID" within the IE "MBMS Selected Services Short" and set it to a value in accordance with subclause 8.6.9.8.

Reference

3GPP TS 25.331 clauses 8.5.27, 8.6.9.6, 8.7.2.4, 8.1.3.3.

8.5.3.1.3 Test purpose

To verify that in idle mode, the UE at session start, re-selects to the preferred Frequency Layer for the MBMS services it has activated.

To verify that at session stop the UE re-selects to the frequency where it has previously camped.

8.5.3.1.4 Method of test

Initial condition

System Simulator:

2 MBMS (Cell 21, Cell 24).

User Equipment:

The UE is in Idle Mode as specified in clause 7.6 of TS 34.108.

The UE is interested in the broadcast service to be provided by the SS (included in MBMS_ACTIVATED_SERVICES variable).

Related ICS/IXIT statements

– MBMS Broadcast service application available on UE Yes/No.

Test procedure

The UE receives, at notification via MCCH, an MBMS MODIFIED SERVICES INFORMATION message including a preferred frequency in the IE “MBMS preferred frequency”.

The UE shall consider this frequency as the preferred frequency layer for cell re-selection and re-select to Cell 24 at session start for the MBMS service it has activated. The UE shall store the frequency information of the frequency on which the UE was operating prior to cell-reselection to the preferred frequency in the variable MBMS_PREV_FREQUENCY_INFORMATION.

The UE shall perform the MCCH acquisition procedure on the new cell.

The SS transmits an MBMS MODIFIED SERVICE INFORMATION message which includes in the “Modified service list” for the MBMS activated service “MBMS required UE action” set to “Acquire counting info” and MBMS ACCESS INFORMATION message, which includes the MBMS Short Transmission ID associated to the MBMS activated service and “Access probability factor – Idle” set to 0 (corresponds to an actual Probability Factor = 1).

The UE shall transmit an RRC CONNECTION REQUEST message, with “Establishment cause” set to “MBMS reception”. The SS transmits a RRC CONNECTION SETUP. The UE establishes an RRC connection and transmits an RRC CONNECTION SETUP COMPLETE message.

The UE receives an MBMS MODIFIED SERVICES INFORMATION message “MBMS required UE action” IE set to “Acquire PTM RB info”. The UE shall apply the MBMS p-t-m radio bearer configuration procedure to acquire the radio bearer configuration for the MBMS service provided by the SS.

The UE starts receiving the indicated p-t-m radio bearer.

The UE receives an MBMS MODIFIED SERVICES INFORMATION message with IE “MBMS required UE action” set to “Release PTM RB”. The UE shall stop receiving the concerned MBMS service. The variable MBMS_PREV_FREQUENCY_INFO is not empty, and any frequency in SIB11 or SIB12 has the same frequency stored in the variable MBMS_PREV_FREQUENCY_INFO, therefore the UE shall select Cell 21 (suitable UTRA cell in that frequency).

Expected sequence

Step	Direction		Message	Comments
Step	Direction		Message	Comments
Step	UE	SS	Message	Comments
1				The UE is in Idle mode on cell 21.
2			MBMS MODIFIED SERVICES INFORMATION	Service_id = service activated “MBMS required UE action is set to “none (FLC)” and PFL index is set to the index of the frequency of f2 in the preferred frequency list in MBMS GENERAL INFORMATION.
3			MBMS GENERAL INFORMATION	MBMS preferred frequency information is set to f2.
4				The UE re-selects to cell 24. The SS allows 2 modification periods for the UE to reselect before sending the following messages on cell 24.
5			MBMS MODIFIED SERVICES INFORMATION	“MBMS required UE action” IE is set to “Acquire counting info”.
6			MBMS GENERAL INFORMATION	MBMS preferred frequency information set without index into SIB11 neighbour list.
7			MBMS ACCESS INFORMATION	“MBMS short transmission ID” IE set to 1, “Access probability factor – Idle” set to 0 (corresponding to the actual probability factor value 1). SS sends MBMS ACCESS INFORMATION throughout the modification period as defined in 34.108 clause 11.1.2
8			RRC CONNECTION REQUEST	The UE transmits the message with Establishment cause set to “MBMS reception” and in case of MBMS Selected service with the “MBMS Selected Services Short” IE referring to the concerned MBMS Selected service and the corresponding Modification period identity.
9			RRC CONNECTION SETUP
10			RRC CONNECTION SETUP COMPLETE
10a			MBMS MODIFICATION REQUEST	The UE completing the RRC connection Setup procedure shall initiate the MBMS MODIFICATION REQUEST procedure in case of MBMS Selected service. This message may be received at any point after step 10 and before step 12.
11	UE			UE transmits SERVICE REQUEST, with IE "Service type" set to "MBMS Broadcast service Reception”.
12			RRC CONNECTION RELEASE
13			RRC CONNECTION RELEASE COMPLETE	The UE shall enter idle mode.
14	SS			The following MBMS messages sent on the MCCH will be received in the next Modification Period.
15			MBMS MODIFIED SERVICES INFORMATION	“MBMS required UE action” IE is set to "Acquire PTM RB info".
16			MBMS GENERAL INFORMATION	MBMS preferred frequency information set without index into SIB11 neighbour list.
17	SS			The following MBMS messages sent on the MCCH will be received in a new Modification Period.
18			VOID
19			MBMS MODIFIED SERVICES INFORMATION	“MBMS required UE action” IE is set to "Release PTM RB”.
20				The UE stops receiving the concerned MBMS service and reselects to Cell 21.
21			CALL C.1	If the test result of C.1 indicates that UE is in Idle Mode state, the test passes, otherwise it fails.

Specific message contents

All messages have the same content as defined in 34.108 clause 9.1.1 with the following exceptions:

MBMS MODIFIED SERVICES INFORMATION (Step 2)

Information Element	Value/remark
Modified service list	Only 1 entry
– MBMS Transmission identity	MBMS Transmission identity indicating MBMS activated service
– MBMS required UE action	None (FLC)
– MBMS preferred frequency
– PFL index	Index of the frequency of Cell 24 in the preferred frequency list

MBMS GENERAL INFORMATION(Step 3)

Information Element	Value/remark
MBMS preferred frequency information	Only 1 entry
MBMS preferred frequency list
– MBMS preferred frequency	Value N corresponds with the n^th frequency included in the IE New inter-frequency cells that is specified within SIB 11, corresponding to cell 24 frequency (f2).
– CHOICE Layer convergence information	No HCS
– Qoffmbms	Infinity

MBMS MODIFIED SERVICES INFORMATION (Step 5)

Information Element	Value/remark
Modified service list	Only 1 entry
-MBMS Transmission identity	MBMS Transmission identity indicating MBMS activated service
-MBMS required UE action	Acquire counting info
– MBMS preferred frequency	–
– PFL index	Set to the index of the frequency of Cell 24 in the preferred frequency list

MBMS GENERAL INFORMATION (Steps 6 and 16)

Information Element	Value/remark
MBMS preferred frequency information	Only 1 entry
MBMS preferred frequency list
– MBMS preferred frequency	Not present (indicates PFL is current cell frequency)
– CHOICE Layer convergence information	No HCS
– Qoffmbms	Infinity

MBMS ACCESS INFORMATION (Step 7)

Information Element	Value/remark
Service list	Only 1 entry
– MBMS short transmission ID	Index to the MBMS transmission identity in the previous MBMS MODIFIED SERVICES INFORMATION
– Access probability factor – Idle	0 (corresponding to the actual probability factor value 1)
– Connected mode counting scope
– URA_PCH	FALSE
– CELL_PCH	FALSE
– CELL_FACH	FALSE

MBMS MODIFICATION REQUEST (steps 10a)

Information Element	Value/remark
MBMS preferred frequency request	Check that the IE is not present
MBMS RB list requested to be released	Check that the IE is not present
MBMS Selected Service Info
– CHOICE Status	Some
– MBMS Selected Services Full
– MBMS Selected Service ID	Only 1 entry
– MBMS Service ID	MBMS service ID of the activated MBMS service
– CHOICE PLMN identity	Check to see that one of the below choice element is present
– SameAs-MIB	(no data)
– explicitPLMN_Id	Check to see if it is set to the same value as "PLMN ID” in the Master Information block transmitted for the current serving cell.

MBMS MODIFIED SERVICES INFORMATION (Step 15)

Information Element	Value/remark
Modified service list	1
-MBMS Transmission identity	MBMS Transmission identity indicating MBMS activated service
-MBMS required UE action	Acquire PTM RB info
– MBMS preferred frequency	–
– PFL index	Set to the index of the frequency of Cell 24 in the preferred frequency list

MBMS MODIFIED SERVICES INFORMATION (Step 19)

Information Element	Value/remark
Modified service list	1
-MBMS Transmission identity	MBMS Transmission identity indicating MBMS activated service
-MBMS required UE action	‘Release PTM RB’

8.5.3.1.1.5 Test requirements

At step 8, the UE shall send an RRC CONNECTION REQUEST message on Cell 24 with Establishment cause set to “MBMS reception”.

At step 21, the test result of C.1 shall indicate that the UE is in idle mode on Cell 21.

8.5.3.1m MBMS Session Start (Frequency Layer Convergence)/Session Stop (Frequency Layer Dispersion) in Idle mode / MBMS Multicast Service

8.5.3.1m.1 Definition

This test is applicable for all UEs that support MBMS multicast services.

8.5.3.1m.2 Conformance requirement

Same conformance requirement as in clause 8.5.3.1.2

8.5.3.1m.3 Test purpose

Same test purpose as in clause 8.5.3.1.3.

8.5.3.1m.4 Method of test

Initial condition

System Simulator:

2 MBMS cells, Cell 21, Cell 24.

User Equipment:

The UE is in Idle Mode as specified in clause 7.6 of TS 34.108.

The UE has joined the multicast service to be provided by the SS (included in MBMS_ACTIVATED_SERVICES variable).

Related ICS/IXIT statements

– MBMS Multicast service application available on UE Yes/No.

Test procedure

Same test procedure as in clause 8.5.3.1.4, except that at step 11 UE transmits Service Request, with IE "Service type" set to "MBMS Multicast service Reception”.

Specific message contents

Same specific messages contents as in clause 8.5.3.1.4

8.5.3.1m.5 Test requirements

Same test requirement as in clause 8.5.3.1.5.

8.5.3.2 MBMS Session Start (Frequency Layer Convergence)/Session Stop (Frequency Layer Dispersion) in CELL_PCH / MBMS Broadcast Service

8.5.3.2.1 Definition

This test is applicable for all UEs supporting MBMS broadcast services.

8.5.3.2.2 Conformance requirement

The UE shall perform the MBMS frequency layer selection procedure upon receiving the IE "MBMS Preferred frequency information", when specified explicitly e.g. as in subclause 8.6.9.2, or when the preferred MBMS service changes.

The UE shall:

1> if there exist two or more preferred frequencies for services included in variable MBMS_ACTIVATED_SERVICES:

2> request from upper layers the priorities of the different MBMS services included in variable MBMS_ACTIVATED_SERVICES for which a preferred frequency has been received.

1> if the UE is in idle mode:

2> if a preferred frequency layer applies for a service included in variable MBMS_ACTIVATED_SERVICES:

3> select the preferred frequency indicated for the MBMS service(s) prioritised most by upper layers for which a preferred frequency exists as the preferred frequency.

1> if the UE is in CELL_FACH, CELL_PCH or URA_PCH state; and

1> if there exists one or more preferred frequencies for services included in variable MBMS_ACTIVATED_SERVICES and the variable MBMS_PL_SERVICE_RESTRICTION_INFO_DEDICATED is set to FALSE:

2>if the IE "RAB information" in the variable ESTABLISHED_RABS is not empty:

3> if the current frequency is the frequency corresponding with the preferred frequency indicated for the MBMS service(s) prioritised most by upper layers for which a preferred frequency exists:

4> select the current frequency as the preferred frequency.

3> else:

4> if there exists one or more preferred frequencies for services included in variable MBMS_ACTIVATED_SERVICES for which the IE "MBMS PL Service Restriction Information" has not been received in the MBMS GENERAL INFORMATION message:

5> select the preferred frequency indicated for the MBMS service(s) prioritised most by upper layers for which a preferred frequency exists for which the IE "MBMS PL Service Restriction Information" has not been received in the MBMS GENERAL INFORMATION message as the preferred frequency.

2> else:

3> select the preferred frequency indicated for the MBMS service(s) prioritised most by upper layers for which a preferred frequency exists as the preferred frequency.

…

1> if a preferred frequency has been selected:

2> if the UE is not in CELL_DCH state:

3> apply the cell-reselection procedure as described in [4], using the received "MBMS Preferred frequency information" applicable to the selected frequency:

4> if HCS is not used, and the IE "Qoffmbms" is not present for the MBMS preferred frequency:

5> consider the cells on the MBMS preferred frequency having a Qoffmbms equal to "infinity".

4> if HCS is used, and the IE "HCS_OFFmbms" is not present for the MBMS preferred frequency:

5> consider the cells on the MBMS preferred frequency having the highest HCS priority level.

3> if the UE re-selects to a cell on the indicated preferred frequency:

4> if the UE is in CELL_FACH, CELL_PCH or URA_PCH:

5> act according to subclause 8.3.1.2.

4> store the frequency information of the frequency on which the UE was operating prior to cell-reselection to the preferred frequency in the variable MBMS_PREV_FREQUENCY_INFORMATION.

4> apply the MCCH acquisition procedure, as specified in subclause 8.7.2.

1> else:

2> if the UE is not in CELL_DCH state:

3> stop applying any "MBMS Preferred frequency information".

…

If the IE "MBMS required UE action" is included and concerns an MBMS activated service the UE shall:

1> if the "MBMS required UE action" is set to ‘None’:

2> take no action with respect to this IE.

1> if the IE "MBMS required UE action" is set to ‘Acquire counting info’ or set to ‘Acquire counting info– PTM RBs unmodified’:

2> perform the MBMS counting procedure as specified in subclause 8.7.4;

1> if the IE "MBMS required UE action" is set to ‘Acquire PTM RB info’; or

1> if the IE "MBMS required UE action" is set to ‘Acquire counting info– PTM RBs unmodified’ and the UE is not receiving a p-t-m RB for the concerned service:

2> act upon the MBMS COMMON P-T-M RB INFORMATION, MBMS CURRENT CELL P-T-M RB INFORMATION and the MBMS NEIGHBOURING CELL P-T-M RB INFORMATION message, if received, in accordance with subclause 8.7.5;

…

1> if the IE "MBMS required UE action" is set to ‘Release PTM RB’:

2> stop receiving the concerned MBMS service;

2> if the UE is in a state other than CELL_DCH (for FDD) or if the UE is in Idle mode, URA_PCH or CELL_PCH state (for TDD); and

2> if the UE does not decide to receive an MBMS service; and

2> if the variable MBMS_PREV_FREQUENCY_INFO is not empty:

3> if any frequency in SIB11 or SIB12 has the same frequency stored in the variable MBMS_PREV_FREQUENCY_INFO:

4> select a suitable UTRA cell in that frequency.

4> if no suitable UTRA cell in that frequency is found:

5> select a suitable UTRA cell in another frequency.

3> if no frequency in SIB11 or SIB12 has the same frequency stored in the variable MBMS_PREV_FREQUENCY_INFO.

4> select a frequency randomly among the inter-frequencies indicated in SIB11 or SIB12.

5> select a suitable UTRA cell in the selected frequency.