How to test features which are not implemented or tested in early devices???
In order to solve this problem Feature Group Indicators ( FGI) are used for mandatory features which may not have been implemented and tested in early devices.
Where do you find FGI Information?
FGI are included within the 'UE EUTRA Capability' information element of the UE Capability Information message. (It is optional and FGI information is not always included in UE Capability information message.)
How FGI is Signalled?
FGI are signalled using a bitmap where each bit corresponds to specific area of functionality. The inclusion of FGI within the UE Capability Information message is optional. Excluding the FGI bitmap indicates that the UE supports all of the functionality associated with the set of supported radio access technologies.
Does 3GPP specify FGI bitmap?
Yes!!!
3GPP TS 36.331 specifies a first FGI bitmap for the release 8 version of the specification. Second FGI bitmap for the release 10 version of the specifications.
3GPP release 8 feature group indicators (FGI)
- Release 8 FGI bitmap has a length of 32 bits but only the first 30 bits are specified for use.
- Bit 31 and 32 should (are) always signalled with a value 0.
- Other bits are signalled with a value of 1 when the associated feature is implemented and tested
Overview of 3GPP release 8 FGI bitmap is shown in the Table below.
3GPP release 10 feature group indicators (FGI)
- Release 10 FGI bitmap also has a length of 32 bits but only the first 16 bits are specified for use.
- Bits 17 to 32 should (are) always be signalled with a value of 0.
- Other bits are signalled with a value of 1 when the associated feature is implemented and tested.
- Bits belonging to release 10 FGI bitmap are allocated indices which are numbered from 101 to 132.
Overview of 3GPP Release 10 FGI bitmap is shown in the Table below.
For Credits and references you can look into 3GPP TS 36.331.
In case if you have any questions, please comment below.