38.3313GPPNRProtocol specificationRadio Resource Control (RRC)Release 15TS
Short Messages can be transmitted on PDCCH using P-RNTI with or without associated Paging message using Short Message field in DCI format 1_0 (see TS 38.212 , clause 22.214.171.124.1).
Table 6.5-1 defines Short Messages. Bit 1 is the most significant bit.
Table 6.5-1: Short Messages
If set to 1: indication of a BCCH modification other than SIB6, SIB7 and SIB8.
If set to 1: indication of an ETWS primary notification and/or an ETWS secondary notification and/or a CMAS notification.
3 – 8
Not used in this release of the specification, and shall be ignored by UE if received.