OSI mean Other SI (i.e, SIBs other than SIB1). The scheduling/broadcasting of OSI is specified as follows.

• PDCCH/DCI 1_0 SearchSpace for OSI is configured by searchSpaceOtherSystemInformation. If this IE is not configured, PDCCH/DCI 1_0 SearchSpace for OSI is assumed to be transmitted in the same CORESET (i.e, CORESET0) as SIB1.
• High Level Scheduling (e.g, Which OSI will be transmitted in which period etc is specified in si-SchedulingInfo IE in SIB1.   

36.331-f30

SIB1 ::=        SEQUENCE {

    cellSelectionInfo                   SEQUENCE {

        q-RxLevMin                          Q-RxLevMin,

        q-RxLevMinOffset                    INTEGER (1..8)      OPTIONAL,   -- Need R

        q-RxLevMinSUL                       Q-RxLevMin          OPTIONAL,   -- Need R

        q-QualMin                           Q-QualMin           OPTIONAL,   -- Need R

        q-QualMinOffset                     INTEGER (1..8)      OPTIONAL    -- Need R

    }    OPTIONAL,   -- Need S

    cellAccessRelatedInfo               CellAccessRelatedInfo,

    connEstFailureControl               ConnEstFailureControl   OPTIONAL,   -- Need R

    si-SchedulingInfo                   SI-SchedulingInfo       OPTIONAL,   -- Need R

    servingCellConfigCommon                ServingCellConfigCommonSIB    OPTIONAL,   -- Need R

    ims-EmergencySupport                ENUMERATED {true}             OPTIONAL,   -- Need R

    eCallOverIMS-Support                ENUMERATED {true}             OPTIONAL,   -- Cond Absent

    ue-TimersAndConstants               UE-TimersAndConstants         OPTIONAL,   -- Need R

    uac-BarringInfo                     SEQUENCE {

        uac-BarringForCommon                UAC-BarringPerCatList     OPTIONAL,   -- Need S

        uac-BarringPerPLMN-List             UAC-BarringPerPLMN-List   OPTIONAL,   -- Need S

        uac-BarringInfoSetList              UAC-BarringInfoSetList,

        uac-AccessCategory1-SelectionAssistanceInfo CHOICE {

            plmnCommon                      UAC-AccessCategory1-SelectionAssistanceInfo,

            individualPLMNList              SEQUENCE (SIZE (2..maxPLMN))

                                               OF UAC-AccessCategory1-SelectionAssistanceInfo

        }   OPTIONAL

    }     OPTIONAL,   -- Need R

    useFullResumeID                     ENUMERATED {true}    OPTIONAL,   -- Need N

    lateNonCriticalExtension            OCTET STRING         OPTIONAL,

    nonCriticalExtension                SEQUENCE{}           OPTIONAL

}

SI-SchedulingInfo ::= SEQUENCE {

   schedulingInfoList                  SEQUENCE (SIZE (1..maxSI-Message)) OF SchedulingInfo,

   si-WindowLength                      ENUMERATED {s5, s10, s20, s40, s80, s160, s320,

                                                    s640, s1280},

   si-RequestConfig                     SI-RequestConfig OPTIONAL, -- Cond MSG-1

   si-RequestConfigSUL                  SI-RequestConfig OPTIONAL, -- Cond SUL-MSG-1

   systemInformationAreaID              BIT STRING (SIZE (24)) OPTIONAL, -- Need R

   ...

}

 SchedulingInfo ::= SEQUENCE { 

   si-BroadcastStatus                   ENUMERATED {broadcasting, notBroadcasting}, 

   si-Periodicity                       ENUMERATED {rf8, rf16, rf32, rf64, rf128, rf256, rf512}, 

   sib-MappingInfo                     SIB-Mapping 

} 

SIB-Mapping ::= SEQUENCE (SIZE (1..maxSIB)) OF SIB-TypeInfo

SIB-TypeInfo:= SEQUENCE { :

   type                                 ENUMERATED {sibType2, sibType3, sibType4, sibType5, :

                                                    sibType6, sibType7, sibType8, sibType9, :

                                                    spare8, spare7, spare6, spare5, spare4, :

                                                    spare3, spare2, spare1,... }, :

   valueTag                             INTEGER (0..31) OPTIONAL, -- Cond SIB-TYPE :

   areaScope                            ENUMERATED {true} OPTIONAL -- Need S :

}  :

SI-RequestConfig::= SEQUENCE {

   rach-OccasionsSI SEQUENCE {

      rach-ConfigSI                      RACH-ConfigGeneric,

      ssb-perRACH-Occasion               ENUMERATED {oneEighth, oneFourth, oneHalf, one, two,

                                                     four, eight, sixteen}

   } OPTIONAL, -- Need R

   si-RequestPeriod                      ENUMERATED {one, two, four, six, eight, ten, twelve,

                                                     sixteen} OPTIONAL,

   si-RequestResources                    SEQUENCE(SIZE (1..maxSI-Message)) OF SI-RequestResources

}

SI-RequestResources ::= SEQUENCE {

   ra-PreambleStartIndex                 INTEGER (0..63),

   ra-AssociationPeriodIndex             INTEGER (0..15) OPTIONAL, -- Need R

   ra-ssb-OccasionMaskIndex              INTEGER (0..15) OPTIONAL -- Need R

}

ServingCellConfigCommonSIB ::=      SEQUENCE {

    downlinkConfigCommon                DownlinkConfigCommonSIB,

    uplinkConfigCommon                  UplinkConfigCommonSIB   OPTIONAL,   -- Need R

    supplementaryUplink                 UplinkConfigCommonSIB   OPTIONAL,   -- Need R

    n-TimingAdvanceOffset               ENUMERATED { n0, n25560, n39936 }   OPTIONAL, -- Need S

    ssb-PositionsInBurst                    SEQUENCE {

        inOneGroup                          BIT STRING (SIZE (8)),

        groupPresence                       BIT STRING (SIZE (8))                                       OPTIONAL -- Cond Above6GHzOnly

    },

    ssb-PeriodicityServingCell          ENUMERATED {ms5, ms10, ms20, ms40, ms80, ms160},

    tdd-UL-DL-ConfigurationCommon       TDD-UL-DL-ConfigCommon    OPTIONAL, -- Cond TDD

    ss-PBCH-BlockPower                  INTEGER (-60..50),

    ...

}

DownlinkConfigCommonSIB ::=     SEQUENCE {

    frequencyInfoDL                 FrequencyInfoDL-SIB,

    initialDownlinkBWP              BWP-DownlinkCommon,

    bcch-Config                     BCCH-Config,

    pcch-Config                     PCCH-Config,

    ...

}

BWP-DownlinkCommon ::=      SEQUENCE {

    genericParameters   BWP,

    pdcch-ConfigCommon  SetupRelease { PDCCH-ConfigCommon }

    pdsch-ConfigCommon  SetupRelease { PDSCH-ConfigCommon }

    ...

}

PDCCH-ConfigCommon ::=                  SEQUENCE {

    commonControlResourcesSets      SEQUENCE (SIZE(1..2)) OF ControlResourceSet     OPTIONAL,

    commonSearchSpaces              SEQUENCE (SIZE(1..4)) OF SearchSpace            OPTIONAL, 

    searchSpaceSIB1                         SearchSpaceId             OPTIONAL, 

     searchSpaceOtherSystemInformation       SearchSpaceId             OPTIONAL,   

    pagingSearchSpace                       SearchSpaceId             OPTIONAL,  

    ra-ControlResourceSet                   ControlResourceSetId      OPTIONAL,   

    ra-SearchSpace                          SearchSpaceId             OPTIONAL,

    ...

}

Reference

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