8.2.26 Information Exchange Initiation

25.4333GPPRelease 17TSUTRAN Iub interface Node B Application Part (NBAP) signalling

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

8.2.26.1 General

This procedure is used by a CRNC to request the initiation of information provisioning from a Node B.

8.2.26.2 Successful Operation

Figure 27L: Information Exchange Initiation procedure, Successful Operation

The procedure is initiated with the INFORMATION EXCHANGE INITIATION REQUEST message sent from the CRNC to the Node B using the Node B Control Port.

Upon reception, the Node B shall provide the requested information according to the Information Type Item IE. Unless specified below, the meaning of the parameters are given in other specifications.

If the Information Type IE contains a GANSS Generic Data IE, at least one of the GANSS Navigation Model And Time Recovery, GANSS Time Model GNSS-GNSS, GANSS UTC Model, GANSS Almanac, GANSS Real Time Integrity, GANSS Data Bit Assistance, GANSS Additional Navigation Models And Time Recovery, GANSS Additional UTC Models, GANSS Auxiliary Information, DBDS Corrections Request, BDS Ionospheric Grid Model Request IEs shall be present in the GANSS Generic Data IE.

– If the GANSS Generic Data IE does not contain the GANSS ID IE, the Node B shall assume that the corresponding GANSS is "Galileo".

Information Report Characteristics
The Information Report Characteristics IE indicates how the reporting of the information shall be performed.

If the Information Report Characteristics IE is set to "On Demand", the Node B shall report the requested information immediately.

If the Information Report Characteristics IE is set to "Periodic", the Node B shall immediately report the requested information and then shall periodically initiate the Information Reporting procedure for all the requested information, with the requested reporting frequency.

If the Information Report Characteristics IE is set to "On Modification", the Node B shall immediately report the requested information if available. If the requested information is not available at the moment of receiving the INFORMATION EXCHANGE INITIATION REQUEST message, but expected to become available after some acquisition time, the Node B shall initiate the Information Reporting procedure when the requested information becomes available. The Node B shall then initiate the Information Reporting procedure in accordance to the following conditions related to the Information Type IE:

1) If the Information Type Item IE is set to "DGPS Corrections", the Node B shall initiate the Information Reporting procedure when either the PRC has drifted from the previously reported value more than the threshold indicated in the PRC Deviation IE in the Information Threshold IE or a change has occurred in the IODE.

2) If the Information Type Item IE is set to "GPS Information" and the GPS Information Item IE includes "GPS Navigation Model & Time Recovery", the Node B shall initiate the Information Reporting procedure for this specific GPS Information Item when a change has occurred regarding either the IODC or the list of visible satellites, identified by the Sat ID IEs.

3) If the Information Type Item IE is set to "GPS Information" and the GPS Information Item IE includes "GPS Ionospheric Model", the Node B shall initiate the Information Reporting procedure for this specific GPS Information Item when any change has occurred.

4) If the Information Type Item IE is set to "GPS Information" and the GPS Information Item IE includes "GPS UTC Model", the Node B shall initiate the Information Reporting procedure for this specific GPS Information Item when a change has occurred in the t_ot or WN_t parameter.

5) If the Information Type Item IE is set to "GPS Information" and the GPS Information Item IE includes "GPS Almanac", the Node B shall initiate the Information Reporting procedure for this specific GPS Information Item when a change in the t_oa or WN_a parameter has occurred.

6) If the Information Type Item IE is set to "GPS Information" and the GPS Information Item IE includes "GPS Real-Time Integrity", the Node B shall initiate the Information Reporting procedure for this specific GPS Information Item when any change has occurred.

7) If the Information Type Item IE is set to "DGANSS Corrections", the Node B shall initiate the Information Reporting procedure when either the PRC has drifted from the previously reported value more than the threshold indicated in the PRC Deviation IE in the Information Threshold IE or a change has occurred in the IOD.

8) If the Information Type Item IE is set to "GANSS Information" and the GANSS Information IE includes the GANSS Navigation Model And Time Recovery IE, the Node B shall initiate the Information Reporting procedure for this specific GANSS Information item when a change has occurred regarding either the IOD or the list of visible satellites, identified by the Sat ID IEs.

9) If the Information Type Item IE is set to "GANSS Information" and the GANSS Information IE includes the GANSS Ionospheric Model IE, the Node B shall initiate the Information Reporting procedure for this specific GANSS Information item when any change has occurred.

10) If the Information Type Item IE is set to "GANSS Information" and the GANSS Information IE includes the GANSS Time Model IE, the Node B shall initiate the Information Reporting procedure for this specific GANSS Information item when any change has occurred.

11) If the Information Type Item IE is set to "GANSS Information" and the GANSS Information IE includes the GANSS UTC Model IE, the Node B shall initiate the Information Reporting procedure for this specific GANSS Information item when a change has occurred in the t_ot or WN_t parameter.

12) If the Information Type Item IE is set to "GANSS Information" and the GANSS Information IE includes the GANSS Almanac IE, the Node B shall initiate the Information Reporting procedure for this specific GANSS Information item when a change in the T_oa, IOD_a or Week Number parameter has occurred.

13) If the Information Type Item IE is set to "GANSS Information" and the GANSS Information IE includes the GANSS Real Time Integrity IE, the Node B shall initiate the Information Reporting procedure for this specific GANSS Information item when any change has occurred

14) If the Information Type Item IE is set to "GANSS Information" and the GANSS Information IE includes the GANSS Data Bit Assistance IE, the Node B shall initiate the Information Reporting procedure for this specific GANSS Information item when any change has occurred.

15)If the Information Type Item IE is set to "GANSS Information" and the GANSS Information IE includes the GANSS Additional Navigation Models And Time Recovery IE, the Node B shall initiate the Information Reporting procedure for this specific GANSS Information item when a change has occurred regarding either the IOD or the list of visible satellites, identified by the Sat ID IEs.

16) If the Information Type Item IE is set to "GANSS Information" and the GANSS Information IE includes the GANSS Additional Ionospheric Model IE, the Node B shall initiate the Information Reporting procedure for this specific GANSS Information item when any change has occurred.

17) If the Information Type Item IE is set to "GANSS Information" and the GANSS Information IE includes the GANSS Additional UTC Models IE, the Node B shall initiate the Information Reporting procedure for this specific GANSS Information item when a change has occurred in the t_ot,WN_ot, WN_t, or N^A parameter.

18) If the Information Type Item IE is set to "GANSS Information" and the GANSS Information IE includes the GANSS Earth Orientation Parameters IE, the Node B shall initiate the Information Reporting procedure for this specific GANSS Information item when a change has occurred in the t_EOP parameter.

19) If the Information Type Item IE is set to "GANSS Information" and the GANSS Information IE includes the GANSS Auxiliary Information IE, the Node B shall initiate the Information Reporting procedure for this specific GANSS Information item when a change has occurred in the Signals Available or Channel Number IE parameter.

20) If the Information Type Item IE is set to "GANSS Information" and the GANSS Information IE includes the DBDS Corrections Request IE, the Node B shall initiate the Information Reporting procedure for this specific GANSS Information item when any change has occurred.

21) If the Information Type Item IE is set to "GANSS Information" and the GANSS Information IE includes the BDS Ionospheric Grid Model Request IE, the Node B shall initiate the Information Reporting procedure for this specific GANSS Information item when any change has occurred.

22) If any of the above Information Type IEs becomes temporarily unavailable, the Node B shall initiate the Information Reporting procedure for this specific Information Item by indicating "Information Not Available" in the Requested Data Value Information IE. If the Information becomes available again, the Node B shall initiate the Information Reporting procedure for this specific Information.

Response message
If the Node B is able to initiate the information provision requested by the CRNC, it shall respond with the INFORMATION EXCHANGE INITIATION RESPONSE message sent over the Node B Control Port. The message shall include the same Information Exchange ID that was included in the INFORMATION EXCHANGE INITIATION REQUEST message. When the Report Characteristics IE is set to "On Modification" or "Periodic", the INFORMATION EXCHANGE INITIATION RESPONSE message shall contain the requested data if the data are available. When the Report Characteristics IE is set to "On Demand", the INFORMATION EXCHANGE INITIATION RESPONSE message shall contain the Requested Data Value IE.

If the Requested Data Value IE contains the GANSS Common Data IE, at least one of the GANSS Ionospheric Model , GANSS RX Pos, GANSS Additional Ionospheric Model, or GANSS Earth Orientation Parameters IEs shall be present.

Any GANSS Generic Data IE associated with a given GANSS included in the Requested Data Value IE shall contain at least one of the DGANSS Corrections, GANSS Navigation Model And Time Recovery, GANSS Time Model, GANSS UTC Model, GANSS Almanac, GANSS Real Time Integrity, GANSS Data Bit Assistance, GANSS Additional Time Models, GANSS Additional Navigation Models And Time Recovery, GANSS Additional UTC Models, GANSS Auxiliary Information, DBDS Corrections, or BDS Ionospheric Grid Model IEs.

– If the GANSS Generic Data IE does not contain the GANSS ID IE, the corresponding GANSS is "Galileo".

– The DGANSS Corrections IE contains one or several DGANSS Information IE(s), each of them associated with a GANSS Signal. A DGANSS Information IE for a particular GANSS that does not contain the GANSS Signal ID IE is by default associated with the default signal defined in TS 25.331 [18], clause 10.3.3.45a.

– The DBDS Corrections IE contains one or several DBDS information IE(s), each of them associated with a GANSS Signal. A DBDS information IE for a particular GANSS that does not contain the GANSS Signal ID IE is by default associated with the default signal defined in TS 25.331 [18], clause 10.3.3.45a.

– The GANSS Real Time Integrity IE contains one or several Satellite Information IEs, each of them associated with a satellite and a GANSS Signal. A Satellite Information IE for a particular GANSS that does not contain the Bad GANSS Signal ID IE is by default associated with all the signals of the corresponding satellite (see [39, 43, 44, 45, 46, 47 48]).

If the Information Type Item IE is set to "GANSS Information" and the GANSS Information IE includes the GANSS Time Model GNSS-GNSS IE with exactly one bit set to value "1", the Node B shall include the GANSS Time Model IE in the Requested Data Value IE with the requested time information.

If the Information Type Item IE is set to "GANSS Information" and the GANSS Information IE includes the GANSS Time Model GNSS-GNSS IE with more than one bit set to value "1, the Node B shall include the GANSS Additional Time Models IE in Requested Data Value IE with the requested time information for each GANSS.

If the Information Type Item IE is set to "DGPS Corrections", the Node B shall include the DGPS Corrections IE in Requested Data Value IE with the DGNSS Validity Period IE included, if available.

If the Information Type Item IE is set to "DGANSS Corrections", the Node B shall include the DGANSS Corrections IE in Requested Data Value IE with the DGNSS Validity Period IE included, if available.

If the Information Type Item IE is set to "GPS Almanac", the Node B shall include the GPS Almanac IE in Requested Data Value IE with the Complete Almanac Provided IE included, if available.

If the Information Type Item IE is set to "GANSS Almanac", the Node B shall include the GANSS Almanac IE in Requested Data Value IE with the Complete Almanac Provided IE included, if available.

If the Information Type Item IE is set to "GANSS Time Model GNSS-GNSS", the Node B shall include the GANSS Time Model IE in Requested Data Value IE with the Delta_T IE included, if available.

8.2.26.3 Unsuccessful Operation

Figure 27M: Information Exchange Initiation procedure, Unsuccessful Operation

If the Information Type Item received in the Information Type Item IE indicates a type of information that cannot be provided, the Node B shall regard the Information Exchange Initiation procedure as failed.

If the requested information provision cannot be initiated, the Node B shall send the INFORMATION EXCHANGE INITIATION FAILURE message over the Node B control port. The message shall include the same Information Exchange ID that was used in the INFORMATION EXCHANGE INITIATION REQUEST message and the Cause IE set to an appropriate value.

Typical cause values are as follows:

Radio Network Layer Cause

– Information temporarily not available.

– Information Provision not supported for the object.

8.2.26.4 Abnormal Conditions

If the Information Report Characteristics IE is set to "On Modification", and the Information Type Item IE is set to "DGPS Corrections", or "DGANSS Corrections", but the Information Threshold IE is not received in the INFORMATION EXCHANGE INITIATION REQUEST message, the Node B shall regard the Information Exchange Initiation procedure as failed.

If the Information Type Item IE is not set to "DGPS Correction" or "DGANSS Corrections", the Information Report Characteristics IE is set to "On Modification" and the Information Threshold IE is included in the INFORMATION EXCHANGE INITIATION REQUEST message, the Node B shall regard the Information Exchange Initiation procedure as failed.