8.6.9 MBMS specific information elements
25.3313GPPProtocol specificationRadio Resource Control (RRC)Release 17TS
The UE shall perform the generic actions defined in this subclause only for the information elements corresponding with services that are included in variable MBMS_ACTIVATED_SERVICES.
8.6.9.1 Continue MCCH Reading
If the "Continue MCCH Reading " is included the UE shall:
1> if the IE "Continue MCCH reading " is set to ‘TRUE’:
2> continue receiving the MBMS MODIFIED SERVICES INFORMATION from MCCH in the next modification period and act upon it as specified in subclause 8.7.3.4.
8.6.9.1a MBMS dynamic persistence level
If the IE "MBMS dynamic persistence level" is included the UE shall:
1> Apply the dynamic persistence level in place of that broadcast in SIB 7 for MBMS related PRACH transmissions that are made within the modification period in which this IE was received.
8.6.9.2 MBMS PL Service Restriction Information
The UE shall:
1> if the UE receives a Radio Bearer Control message or a CELL UPDATE CONFIRM message:
2> if the IE "MBMS PL Service Restriction Information" is included:
3> set the variable MBMS_PL_SERVICE_RESTRICTION_INFO_DEDICATED to TRUE.
2> else:
3> set the variable MBMS_PL_SERVICE_RESTRICTION_INFO_DEDICATED to FALSE.
1> if the UE receives a Radio Bearer Control message or a CELL UPDATE CONFIRM message or an MBMS GENERAL INFORMATION message:
2> perform the MBMS frequency selection procedure as specified in subclause 8.5.27.
8.6.9.3 MBMS L1 combining schedule
If the IE "MBMS L1 combining schedule" is included the UE may:
1> apply L1 combining between the concerned neighbouring cell’ S-CCPCH and the corresponding current cell’s S-CCPCH for the periods indicated by this IE.
8.6.9.3a MBMS Number of neighbour cells
The UE may:
1> apply the number of neighbour cells to identify if all MBMS NEIGHBOURING CELL P-T-M RB INFORMATION messages have been received from MCCH.
8.6.9.4 MBMS Preferred frequency information
If the IE "MBMS Preferred frequency information" is included the UE shall:
1> if HCS is not used, and the IE "Qoffmbms" is not present for the MBMS preferred frequency:
2> consider the cells on the MBMS preferred frequency having a Qoffmbms equal to "infinity".
1> if HCS is used, and the IE "HCS_OFFmbms" is not present for the MBMS preferred frequency:
2> consider the cells on the MBMS preferred frequency having the highest HCS priority level.
1> perform the MBMS frequency selection procedure as specified in subclause 8.5.27.
8.6.9.4a Void
8.6.9.4b MBMS p-t-m activation time
Upon reception of the IE "MBMS p-t-m activation time", for the services included in the IE "Modified service list" in the MBMS MODIFIED SERVICES INFORMATION message, and, if the IE "MBMS all unmodified p-t-m services" is included in the MBMS MODIFIED SERVICES INFORMATION message, for the services included in the IE "Unmodified services list" included in the MBMS UNMODIFIED SERVICES INFORMATION message, the UE shall:
1> if the IE "MBMS required UE action" for this service is set to "Acquire PTM RB info":
2> for the current cell:
3> stop using any old configuration on TTIs that are after or contain the time instant as indicated by the IE "MBMS p-t-m activation time";
3> start using the configuration for the S-CCPCH received for that p-t-m bearer in the same modification period as the IE "MBMS p-t-m activation time" on TTIs that are after or that contain the time instant as indicated by the IE "MBMS p-t-m activation time".
2> for neighbouring cells:
3> for the neighbouring cells for which the IE "MBMS transmission time difference" is included:
4> stop using any old configuration on TTIs corresponding to the TTIs of the cell wherein the UE is reading the MCCH from and where the new p-t-m radio bearer information is valid according to the above;
4>> start using the configuration for the S-CCPCH received for that p-t-m bearer in the same modification period as the IE "MBMS p-t-m activation time" on TTIs corresponding to the TTIs of the cell wherein the UE is reading the MCCH from and where the new p-t-m radio bearer information is valid according to the above.
3> for the neighbouring cells for which the IE "MBMS transmission time difference" is not included:
4> stop using any old configuration on TTIs that are after or contain the time instant as indicated by the IE "MBMS p-t-m activation time".
4> start using the configuration for the S-CCPCH received for that p-t-m bearer in the same modification period as the IE "MBMS p-t-m activation time" on TTIs that are after the time instant as indicated by the IE "MBMS p-t-m activation time".
8.6.9.5 MBMS RB list released to change transfer mode
If the IE "MBMS RB list released to change transfer mode" is included the UE shall:
1> perform the service prioritisation procedure as specified in subclause 8.5.26, taking into account that the MBMS service(s) for which the radio bearers are released will be provided via p-t-m radio bearer(s).
8.6.9.6 MBMS Required UE action
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 ‘Request PTP RB’:
2> if the UE is in idle mode:
3> indicate to upper layers that establishment of a PS signalling connection is required to receive the concerned MBMS [5], unless the UE has already requested p-t-p RB establishment in the current modification period, and use the establishment cause set to ‘MBMS ptp RB request’ in the RRC connection establishment procedure.
2> if the UE is in URA_PCH, CELL_PCH or CELL_FACH states:
3> indicate to upper layers to initiate a service request procedure [5] to receive the concerned MBMS service;
3> perform the cell update procedure with cause "MBMS ptp RB request", as specified in subclause 8.3.1.2, unless the UE has already requested p-t-p RB establishment in the current modification period.
2> if the UE is in CELL_DCH:
3> indicate to upper layers to initiate a service request procedure [5] to receive the concerned MBMS service.
1> if the IE "MBMS required UE action" is set to ‘Release PTM RB’:
2> stop receiving the concerned MBMS service;
2> for 1.28 Mcps TDD, if the IE "MBMS PTM RB Release Cause" is present to indicate the actual MBMS PTM RB release cause to UE:
3> pass the value of the IE "MBMS PTM RB Release Cause" to upper layers.
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 decides not to receive an MBMS service indicated on the MCCH; 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.
8.6.9.6a MBMS re- acquire MCCH
If the UE receives the IE " MBMS re- acquire MCCH", the UE shall:
1> perform the MCCH acquisition procedure as specified in subclause 8.7.2.
8.6.9.7 MBMS Service transmissions info list
If the UE receives the IE "MBMS Service transmissions info list", the UE may:
1> discontinue reception of the S-CCPCH on which the IE was received, except for the service transmissions indicated by this IE for the concerned scheduling period.
8.6.9.8 MBMS Short transmission ID
If the IE "MBMS short transmission ID" is included the UE shall:
1> if the value of the "MBMS short transmission ID" is less than or equal to the number of services identified by the IE "Modified services list" included in the MBMS MODIFIED SERVICES INFORMATION message acquired in the same modification period as the one in which the "MBMS short transmission ID" is received:
2> consider the "MBMS short transmission ID" to be an index to the list of services contained in the IE "Modified services list" and apply the MBMS transmission identity specified for this entry.
1> otherwise:
2> compile a list of available MBMS services, as included in the MBMS MODIFIED SERVICES INFORMATION and the MBMS UNMODIFIED SERVICES INFORMATION messages acquired in the same modification period as the one in which the "MBMS short transmission ID" is received:
3> concatenate the services contained in IE "Modified services list" included in the MBMS MODIFIED SERVICES INFORMATION and the services contained in IE "Unmodified services list" included in the MBMS UNMODIFIED SERVICES INFORMATION.
2> consider the ‘MBMS short transmission ID’ to be the index of the entry in the list of available services and apply the MBMS transmission identity specified for this entry.
8.6.9.9 MBMS Transmission identity
If the IE "MBMS transmission identity" is included the UE shall:
1> if upper layers indicate that the MBMS transmission has already been received correctly:
2> ignore the information about this MBMS transmission i.e. continue as if the information about the concerned MBMS transmission was not included in the message.
1> otherwise:
2> act upon the information about the concerned MBMS transmission as specified elsewhere.
The UE behaviour is unspecified if an MBMS transmission identity appears more than once in the combined list of transmissions i.e. the IE is included more than once in the MBMS MODIFIED SERVICES INFORMATION or in the MBMS UNMODIFIED SERVICES INFORMATION, or once in both message.
8.6.9.9a MBMS transmission time difference
The IE "MBMS transmission time difference" indicates the time difference between the transmissions on the current and the neighbour cell i.e. indicating the TTIs that can be L1- combined. The UE shall:
1> derive the parameter Neighbor_Start from the IE MBMS transmission time difference as follows:
MBMS transmission time difference = (Neighbor_Start / Max_TTI_Size) mod 4
where Neighbor_Start is the CFN of the first radio frame in a TTI on the neighbour cell that may be combined with the TTI on the current cell of which the CFN of the first radio frame equals 0 while Max_TTI_Size is the largest TTI size on the S-CCPCHs to be soft combined;
1> in case of partial soft combining, derive the CFN of the first radio frame in a TTI on the neighbour cell that may be combined assuming the same time difference applies.
The maximum delay between S-CCPCH clusters that the UE may combine is set by UE performance requirements.
NOTE: The MBMS transmission time difference is semi-static; it does not vary within or between L1 combining periods nor when full combining is used.
8.6.9.9ab MBSFN cluster frequency
If the cell is operating in MBSFN mode according to subclause 8.1.1.6.3 the UE shall:
1> if for two or more services included in variable MBMS_ACTIVATED_SERVICES the IE "MBSFN cluster frequency" is available:
2> request from upper layers the priorities of the different MBMS services included in variable MBMS_ACTIVATED_SERVICES for which the IE "MBSFN cluster frequency" is available;
2> if the IE "MBSFN cluster frequency" is available for the service with the highest priority included in variable MBMS_ACTIVATED_SERVICES:
3> tune to the frequency indicated in the IE "MBSFN cluster frequency" of that service.
8.6.9.9ac MBSFN frequency list
For FDD and 3.84/7.68 Mcps TDD this IE may be included in system information block 11 in a cell which is not providing MBMS service in MBSFN mode in order to provide information about frequencies providing MBMS service in MBSFN mode. For 1.28 Mcps TDD this IE shall be included in system information block 11 in a cell which is not providing MBMS service in MBSFN only mode but is associated with one or more cells in MBSFN only mode, in order to provide information about frequencies providing MBMS service in MBSFN only mode, and this IE also provides information about the secondary frequencies providing MBMS service in non-MBSFN only mode of current multi-frequency cell.
If the IE "MBSFN frequency list" is included in system information block 11, a UE may consider that all frequencies on which FDD or 3.84/7.68 Mcps TDD cells providing MBMS service in MBSFN mode are listed in the IE "MBSFN frequency list". If the IE "IMB indication" is included in the IE "MBSFN frequency list", the UE shall consider that the cells on the corresponding frequencies are 3.84 Mcps TDD IMB cells providing MBMS service in MBSFN mode.
If the IE "MBSFN frequency list" is included in system information block 11 and no frequency is included in the IE "MBSFN frequency list" a UE may consider that no cell operating in MBSFN mode is available.
For FDD and 3.84/7.68 Mcps TDD if the IE "MBSFN frequency list" is not included in system information block 11 and if services are listed in the variable MBMS_ACTIVATED_services a UE supporting reception of MBMS service in MBSFN mode shall search for cells providing MBMS service in MBSFN mode.
For 1.28 Mcps TDD the IE "Cell parameter ID" in the IE "MBSFN frequency list" included in system information block 11 indicates the cell which is providing MBMS service in MBSFN only mode on the corresponding frequency; if the IE "Cell parameter ID" is not included in the IE "MBSFN frequency list", a UE may consider that the corresponding frequency is the secondary frequency providing MBMS service in non-MBSFN only mode of current multi-frequency cell.
8.6.9.9ad MBSFN inter frequency neighbour list
For FDD, 3.84 Mcps TDD IMB and 3.84/7.68 Mcps TDD, this IE may be signalled in the "MBMS GENERAL INFORMATION" message received in the cells providing MBMS service in MBSFN mode. If the IE "MBSFN inter frequency neighbour list" is included and the UE does not receive a service from this MBSFN cluster, the UE shall:
1> consider that MBMS services transmitted in MBSFN mode are available on these frequencies;
1> if IE "IMB indication" is included:
2> consider that the cells on the corresponding frequencies are 3.84 Mcps TDD IMB cells providing MBMS service in MBSFN mode.
1> if "MBSFN services notified" is indicated for a frequency listed in the IE "MBSFN inter frequency neighbour list":
2> consider that available services provided on this frequency are notified on the current frequency.
1> if at least one frequency is listed for which "MBSFN services not notified" is indicated in the IE "MBSFN inter frequency neighbour list":
2> if the IE "All MBSFN services notified" is included for one frequency, as defined in [21] for FDD and [22] for TDD, on which the UE supports reception in MBSFN mode:
3> attempt to receive notifications on one of the frequencies for which the IE "All MBSFN services notified" is included according to subclause 8.7.3.
2> else:
3> attempt to receive notifications on all frequencies for which the IE “MBSFN services not notified” is indicated as specified in subclause 8.7.3 on that band.
NOTE 1: The UE may not be able to receive frequencies listed in the IE "MBSFN inter frequency neighbour list" on a different band compared to the band on which the information is sent (this depends on UE capabilities).
NOTE 2: The indications for different frequencies (i.e. "MBSFN services notified", "MBSFN services not notified", "All MBSFN services notified") in the MBMS GENERAL INFORMATION message can be different depending on the frequency in which the MBMS GENERAL INFORMATION message has been received.
8.6.9.9ae MBSFN TDM Information
If the IE "MBSFN TDM Information List" is included, the UE shall:
1> assume that the MBMS service identitfied in IE "MBMS short transmission ID" can be received only in frame(s) with the CFN fulfilling the following equation:
(CFN div N) mod TDM_Rep = TDM_Offset + i, i = 0 to TDM_Length – 1
where
– N is the TTI (in number of 10ms frames) of the FACH
– TDM_Rep is the repetition period
– TDM_Offset is the offset
– TDM_Length is the number of TTIs the MBMS Service is transmitted, starting from TDM _Offset
– CFN is set according to subclause 8.5.15.3 (Initialisation for CELL_FACH).
8.6.9.9b MCCH configuration information
If the IE "MCCH configuration information" is included the UE shall:
1> Consider an access information period to start from the frame with the SFN value fulfilling the following equation (where m is the modification period coefficient and a is the access info period coefficient):
SFN mod 2(m – a) = 0
1> Consider a repetition period to start from the frame with the SFN value fulfilling the following equation (where m is the modification period coefficient and r is the repetition period coefficient):
SFN mod 2(m – r) = 0
1> Consider a modification period to start from the frame with the SFN value fulfilling the following equation (where m is the modification period coefficient):
SFN mod 2m = 0
1> configure the RLC entity in the UE used for receiving MCCH in accordance with 8.6.4.9;
1> configure the MAC entity in the UE, used for receiving MCCH, for receiving TCTF field unless the IE ‘TCTF presence’ is received;
8.6.9.10 Next scheduling period
If the IE "Next scheduling period" is included for an MBMS service the UE may:
1> discontinue reception of the given MBMS service for the number of scheduling periods indicated by this IE.
8.6.9.11 TDD MBSFN Information
For TDD if the UE receives "TDD MBSFN Information" (via System Information Block type 5) then the UE shall assume that any CCTrCH configured to use the timeslots indicated by this IE shall use MBSFN Burst Type.
8.6.9.12 Network Standard Time Information
For 1.28Mcps TDD, when UE receives "Network Standard Time Information" via MBMS general information, the UE can adjust its local time settings according to the values in "Network Standard Time Information". The adjustment process is as following:
1) Compare currently SFN and "Correlative SFN", get a difference;
2) Add this difference to "Network Standard Time"
The result is the precise standard time in currently SFN, and then UE can maintain this standard time. How often does UE do this adjustment is a UE implementation.