System Information Blocks (SIBs) in LTE

Михаил Якимов

SIB 1 - cell access and scheduling of other system information (1)

PLMN-Identity Consists of MCC and MNC. The first listed one is the Primary PLMN

p-Max

Value applicable for the cell. If absent the UE applies the maximum power according to the UE capability. If eNB configures the value more than the value supported by the UE then UE will set the max value aupported by the UE capability. Example UE Catagory 3 supports max 23 db

cellReservedForOperatorUse As defined by operator (Reserved/Not_reserved)

trackingAreaCode TAC which is common to the PLMN Identities

cellIdentity Identifies a cell within the PLMN

cellBarred If Barred then UE is not allowed to camp on the cell

intraFreqReselection If enabled, UE will be able to perform Cell-reselection to INTRA-frequency cells

q_RxLevMin Minimum required RX level in the cell

q_RxLevMinOffset

Actual value Qrxlevminoffset = IE value * 2 [dB]. only applied when a cell is evaluated for cell selection as a result of a periodic search for a higher priority PLMN while camped normally in a VPLMN [5]. During this periodic search for higher priority PLMN the UE may check the S criteria of a cell using parameter values stored from a different cell of this higher priority PLMN. Affects the minimum required Rx level in the cell.

SIB 1 (2)

freqBandIndicator indicates the E-UTRA operating band

schedulingInfoList information regarding the presence of SIB type; other than SIB1

si_Periodicity Periodicity of the SI-message in radio frames (SI will be transmitted within the specified radio frame)

sib_MappingInfo carries the List of the SIBs mapped. SIB2 is always present in the first element of schedulingInfoList

si_WindowLength

specifies that a SIB should be transmitted somewhere within the specified window length. Value is in ms. This window starts at the starting sub-frame of the mentioned si_periodicity. SIBs can be received in any of the sub-frame as mentioned in the WindowLength.

systemInfoValueTag

indicates if a change has occurred in the SI messages. UEs may use systemInfoValueTag, e.g. upon return from out of coverage, to verify if the previously stored SI messages are still valid. Additionally, the UE considers stored system information to be invalid after 3 hours from the moment it was successfully confirmed as valid, unless specified otherwise.Common for all SIBs other than MIB, SIB1, SIB10, SIB11 and SIB12.

SIB 2 - radio resource configuration information (1)

ac-BarringInfo Access Class Barring configuration

radioResourceConfig used to specify common radio resource configurations in the system information and in the mobility control information

numberOfRA_Preambles Number of non-dedicated random access preambles

preamblesGroupAConfig_existProvides the configuration for preamble grouping. If the field is not signalled, the size of the random access preambles group A is equal tonumberOfRA-Preambles

powerRampingParameters

powerRampingStep Power ramping factor

preambleInitialReceivedTargetPower Initial preamble power

ra_SupervisionInfo

preambleTransMax Maximum number of preamble transmission

ra_ResponseWindowSize Duration of the RA response window. Value in subframes. Value sf2 corresponds to 2 subframes

mac_ContentionResolutionTimer Timer for contention resolution. Value in subframes. Value sf8 corresponds to 8 subframes

maxHARQ_Msg3Tx 4 Maximum number of Msg3 HARQ transmissions, used for contention based random access

SIB 2 (2)

bcch_Config

modificationPeriodCoeff Actual modification period, expressed in number of radio frames= modificationPeriodCoeff * defaultPagingCycle. n2 corresponds to value 2

pcch_Config

defaultPagingCycle Default paging cycle, used to derive ‘T’. Value rf32 corresponds to 32 radio frames

nB is used as one of parameters to derive the Paging Frame and Paging Occasion

prach_Config used to specify the PRACH configuration in the system information and in the mobility control information

rootSequenceIndex

prach_ConfigIndex

mentions the:Preamble format: 0-4 (For frame structure 1 preamble format is 0-3 and for frame structure 2 it is 0-4) SFN: whether it will be EVEN no. frmae OR any framesubframe number: carrier the subframe no. within the SFN (Look for the table in TS36.211 - Table 5.7.1-2)

highSpeedFlag TRUE corresponds to Restricted set and FALSE to Unrestricted set

zeroCorrelationZoneConfig used for Preamble generation

SIB 2 (3)

pdsch_Config used to specify the common and the UE specific PDSCH configuration

pusch_Config used to specify the common PUSCH configuration and the reference signal configuration for PUSCH and PUCCH

pucch_Config used to specify the common and the UE specific PUCCH configuration

soundingRS_UL_Config used to specify the uplink Sounding RS configuration

uplinkPowerControl used to specify parameters for uplink power control in the system information and in the dedicated signalling

ue_TimersAndConstants Timer values

freqInfo UL carrier frequency and bandwidth

timeAlignmentTimerCommon used to control how long the UE is considered uplink time aligned. Value in subframes

SIB3: Cell-reselection parameters for INTRA-Frequency, INTER-Frequency and Inter-RAT (1)

cellReselectionInfoCommon Cell re-selection information common for cells

q_Hyst This specifies the hysteresis value for cell re-selection ranking criteria. The specified value is added to the serving cell RSRP measurement.

speedStateReselectionPars

Speed dependent reselection parameters. If this field is absent then mobility State Parameters is not present. If q_hystSF is present then it is added to q_hyst. Carrier (-) value so as to reduce the ranking of the serving cell and allows cellreselection to occur easily.

cellReselectionServingFreqInfo Information for Cell re-selection to inter-frequency and inter-RAT cells

s_NonIntraSearch

#used to trigger Interfrequency and IRATfrequency measurements for cell reselection when:- TARGET Interfreq. has lower or equal priority- IRAT freq. has a lower priority# specifies the Srxlev threshold (in dB) for E-UTRAN inter-frequency and inter-RAT measurements.#If the field s-NonIntraSearchP is present, the UE applies the value of s-NonIntraSearchP.# Otherwise if neither s-NonIntraSearch nor s-NonIntraSearchP is present, the UE applies the (default) value of infinity for SnonIntraSearchP.

threshServingLowThis specifies the Srxlev threshold (in dB) below which the serving cell must fall before reselecting towards a lower priority RAT/ frequency. Value in between 0-31dB. Actual value=signalled value*2

cellReselectionPriority

explains the absolute priority of the concerned serving cell frequency /set of frequencies (GERAN)/ bandclass (CDMA2000), as used by the cell reselection procedure. Corresponds with parameter "priority". Value is between 0-7 where 0 means: lowest priority.

SIB3 (2)

intraFreqCellReselectionInfo Cell re-selection information common for intra-frequency cells

q_RxLevMin Minimum required RSRP for cell reselection. value -70 - 22 dbm, Actual value=signalled value*2

s_IntraSearch

# used to trigger intrafreq. measurements# specifies the Srxlev threshold (in dB) for intra-frequency measurements.# If the field s-IntraSearchP is present, the UE applies the value of s-IntraSearchP instead. Otherwise if neither 09s-IntraSearch nor s-IntraSearchP is present, the UE applies the (default) value of infinity for SIntraSearchP.

presenceAntennaPort1is used to09 indicate whether all the neighbouring cells use 09Antenna Port 1. When set to TRUE, the UE may assume that at least two cell-specific antenna ports are used in all neighbouring cells.

neighCellConfig used to provide the information related to MBSFN and TDD UL/DL configuration of neighbour cells.

t_ReselectionEUTRA# specifies the cell reselection timer value# defines time to trigger for cell reselection# The parameter can be set per E-UTRAN frequency

p_Max# max. allowed UL transmit power for intra-frequency neighbouring E-UTRA cells. If absent the UE applies the maximum power according to the UE capability

SIB4: Cell-reselection parameters for Neighbouring INTRA-Frequency

intraFreqNeighCellList[1-16 instances]

List of intra-frequency neighbouring cells with specific cell re-selection parameters

IntraFreqNeighCellInfo

physCellId Physical CellID of the neighbour cell

q-OffsetCell specifies the offset between the two cells. Value -24 - +24dB

intraFreqBlackCellList[1-16 instances]

List of blacklisted intra-frequency neighbouring cells. These type of cells are not considered for cell re-selection

csg_PhysCellIdRange

Set of physical cell identities reserved for CSG cells on the frequency on which this field was received. The received csg-PhysCellIdRange applies if less than 24 hours has elapsed since it was received and it was received in the same primary PLMN. This field is Optional (mandatory for CSG cell)

intraFreqNeighCellList[1-16 instances]

List of intra-frequency neighbouring cells with specific cell re-selection parameters

SIB5: Cell-reselection parameters for INTER-Frequency

InterFreqCarrierFreqInfo can be specified upto 8 carrier frequenciesdl-CarrierFreq carrier frequency helps the UE to search the cells

q-RxLevMinminimum RSRP value of the inter-frequency cell. Value -70 to -22 dBm.Actual value: signalled value * 2

p-Max maximum allowed UL transmit power of the cellt-ReselectionEUTRA defines the time to trigger for cell reselection. Value 0 to 7 sec.t-ReselectionEUTRA-SF scaling factors for Medium and High mobility

threshX-High# Threshold (in dB) used by UE for cell re-selection to a HIGHER priority# The Srxlev of the candiate cell is greater then threshX_High# Value 0 to 31 dB. Actual value= Signaled value * 2

threshX-Low

# Threshold (in dB) used by UE for cell re-selection to a LOWER priority# Cell re-selection is allowed only when Srxlev of the candiate cell is greater then threshX_Low and RSRP of serving cell is less than the value of ThreshServingLowsingalled within SIB3# Value 0 to 31 dB. Actual value= Signaled value * 2

allowedMeasBandwidth defined in terms of Resouce blocks associated with a specific channel bandwidthcellReselectionPriority defines the Abolute priority of the frequency layerneighCellConfig information regarding the neighbouring cellsq-OffsetFreq defines the RSRP measurement offset, applied to all cells on the specified RF carrierinterFreqBlackCellList the mentioned cells are no considered for cell reselection

SIB6: Cell-reselection parameters INTER RAT Frequency

carrierFreqListUTRA_FDD/TDD Information specified for up to 16 instances of RF carriers for FDD or TDDcarrierFreq carrier frequency helps the UE to seachcellReselectionPriority defines the absolute priority of the UMTS. Value 0-7, 0 is the lowest priority

threshX_High

# Threshold (in dB) used by UE for cell re-selection to a HIGHER priority UMTS frequency# The Srxlev of the candiate cell is greater then threshX_High# Value 0 to 31 dB. Actual value= Signaled value * 2

threshX_Low

# Threshold (in dB) used by UE for cell re-selection to a LOWER priority UMTS frequency# Cell re-selection is allowed only when Srxlev of the candiate cell is greater then threshX_Low and RSR of serving cell is less than the value of ThreshServingLowsingalled within SIB3# Value 0 to 31 dB. Actual value= Signaled value * 2

q_RxLevMin minimum RSCP requirement for candiate UMTS cell. Value -60 to -13 dB. Actual value= Signaled value * 2 +1

p_Max Value applicable for the intra-frequency neighbouring E-UTRA cells. If absent the UE applies the maximum power according to the UE capability

q_QualMin# minimum Ec/Io requirement for candiate UMTS cell. Value -24 to 0 dB# applicable for FDD only

t_ReselectionUTRA # defines the time to trigger cell re-selection# value 0 - 7 seconds

t_ReselectionUTRA_SF

# defines the time to trigger cell re-selection# value 0 - 7 seconds# Scaling factors used for Medium and High mobility# Scaling Factors value 0.25, 0.5, 0.75, 1.0. These values decrease the value of T_reselection which allows more rapid cell re-selections

SIB7: Cell-reselection parameters INTER RAT Frequency (GERAN)

t_ReselectionGERAN Time to trigger for reselection. Value 0 to 7 sec. carrierFreqsInfoList[0] carries upto 16 instances of GERAN freq.carrierFreqsstartingARFCN Start of the ARFCNbandIndicator dcs1800 or pcs1900

followingARFCNs ARFCN groups

cellReselectionPriority absolute priority of the GERAN layer. Value 0 to 7, whereas 0 is the lowest priority

ncc_Permitted Network Color Code. Is a bitmap valueq_RxLevMin minimum RSSI value required

p_MaxGERAN maximum allowed UL transmit power

threshX_High# Threshold (in dB) used by UE for cell re-selection to a HIGHER priority frequency# The Srxlev of the candiate cell is greater then threshX_High# Value 0 to 31 dB. Actual value= Signaled value * 2

threshX_Low

# Threshold (in dB) used by UE for cell re-selection to a LOWER priority frequency# Cell re-selection is allowed only when Srxlev of the candiate cell is greater then threshX_Low and RSRP of serving cell is less than the value of ThreshServingLowsingalled within SIB3# Value 0 to 31 dB. Actual value= Signaled value * 2

SIB9: Home eNB name

hnb-Name Carries the name of the home eNB

SIB10: ETWS primary notification

messageIdentifier Identifies the source and type of ETWS notification (earthquake, tsunami warning, any emergency or test message)

serialNumber

Identifies variations of an ETWS notification. -uses various mechanisms to alert the user (display message, play a tone or vibrate, location where the message is applicable, also contains an update number which specifies whether a change is in the message content or not)

warningType# Identifies the warning type of the ETWS primary notification (earthquake, tsunami, etc.) and # provides information on emergency user alert and UE popup

warningSecurityInfo # is optional, only applied when security is applied# Provides security information for the ETWS notification

SIB11: ETWS secondary notification

messageIdentifier Identifies the source and type of ETWS notification (earthquake, tsunami warning, any emergency or test message)

serialNumber

Identifies variations of an ETWS notification. -uses various mechanisms to alert the user (display message, play a tone or vibrate, location where the message is applicable, also contains an update number which specifies whether a change is in the message content or not)

warningMessageSegmentType[last/not last]

Indicates whether the included ETWS warning message segment is the last segment of the complete segment or not

warningMessageSegmentNumber

# allows oedering of the message segments# Segment number of the ETWS warning message segment contained in the SIB. A segment number of zero corresponds to the first segment, one corresponds to the second segment, and so on

warningMessageSegment carries actual segment of the message

dataCodingScheme Identifies the alphabet/coding and the language applied variations of an ETWS notification

SIB12: CMAS notification

messageIdentifier Identifies the source and type of CMAS notification

serialNumber Identifies variations of a CMAS notification

warningMessageSegmentType Indicates whether the included CMAS warning message segment is the last segment or not

warningMessageSegmentNumber

Segment number of the CMAS warning message segment contained in the SIB. A segment number of zero corresponds to the first segment, one corresponds to the second segment, and so on

warningMessageSegment Carries a segment of the Warning Message

dataCodingScheme Identifies the alphabet/coding and the language applied variations of a CMAS notification

SIB13: MBMS control information

Contains the information required to acquire the MBMS control information associated with one or more MBSFN areas • mbsfn-AreaInfoList