5.29 Activation/Deactivation of SCG

38.3213GPPMedium Access Control (MAC) protocol specificationNRRelease 17TS

The network may activate and deactivate the configured SCG.

The MAC entity shall for the configured SCG:

1> if upper layers indicate that SCG is activated:

2> if BFI_COUNTER >= beamFailureInstanceMaxCount for the PSCell or the timeAlignmentTimer associated with PTAG is not running:

3> indicate to upper layers that a Random Access Procedure (as specified in clause 5.1.1) is needed for SCG activation.

2> else:

3> activate the SCG according to the timing defined in TS 38.133 [11] for direct SCG activation.

2> (re-)initialize any suspended configured uplink grants of configured grant Type 1 associated with this PSCell according to the stored configuration, if any, and to start in the symbol according to rules in clause 5.8.2.2;

2> apply normal SCG operation including:

3> SRS transmissions on the PSCell;

3> CSI reporting for the PSCell;

3> PDCCH monitoring on the PSCell;

3> PUCCH transmissions on the PSCell;

3> transmit on RACH on the PSCell;

3> initialize Bj for each logical channel to zero.

1> else if upper layers indicate that the SCG is deactivated:

2> deactivate all the SCells of the SCG according to clause 5.9;

2> deactivate SCG according to the timing defined in TS 38.133 [11];

2> clear any configured downlink assignment and any configured uplink grant Type 2 associated with the PSCell respectively;

2> suspend any configured uplink grant Type 1 associated with the PSCell;

2> reset MAC according to clause 5.12.

1> if the SCG is deactivated:

2> not transmit SRS on the PSCell;

2> not report CSI for the PSCell;

2> not transmit on UL-SCH on the PSCell;

2> not transmit PUCCH on the PSCell;

2> not transmit on RACH on the PSCell;

2> not monitor the PDCCH on the PSCell.