PDCP UL split and pre-processing
According to an aspect, a UE in an uplink split-bearer configuration is configured to transmit PDUs by a first RLC entity via a first uplink transmission path and/or by a second RLC entity via a second uplink transmission path. The UE determines a total amount of data volume from PDCP data volume and RLC data volume pending for initial transmission in the two RLC entities. The UE decides whether submission of PDCP data volume is allowed to either of the two RLC entities or to only the first RLC entity, based on whether the total amount of data volume meets or exceeds a first threshold. The UE also reports the PDCP data volume to both the first and second uplink transmission paths or only the first uplink transmission path, based on whether the total amount of data volume meets or exceeds a first threshold.
1. A method by a user equipment (UE) configured to transmit packet data units (PDUs) by a first Radio Link Control (RLC) entity and/or by a second RLC entity, the method comprising:
determining a total amount of data volume pending for transmission, wherein the total amount of data volume comprises Packet Data Convergence Protocol (PDCP) data volume buffered for transmission and RLC data volume pending for initial transmission in the two RLC entities; and
indicating the PDCP data volume to at least a first uplink transmission path, based on whether the total amount of data volume meets or exceeds a first threshold, wherein the indicating comprises:
in response to determining that the total amount of data volume meets or exceeds the first threshold, indicating the PDCP data volume to both the first uplink transmission path and a second uplink transmission path; and
in response to determining that the total amount of data volume does not meet the first threshold, indicating the PDCP data volume to only the first uplink transmission path.
2. The method according to claim 1 , wherein:
the PDCP data volume comprises PDCP service data unit (SDU) and PDU data volume buffered for transmission; and
the RLC data volume comprises RLC SDU and PDU data volume pending for initial transmission.
3. The method according to claim 1 , wherein the first uplink transmission path is a prioritized uplink transmission path and the second uplink transmission path is an unprioritized uplink transmission path.
4. The method according to claim 1 , wherein the first RLC entity belongs to a Master Cell Group (MCG) and the second RLC entity belongs to a Secondary Cell Group (SCG).
5. The method according to claim 1 , further comprising, in response to determining that the total amount of data volume does not meet the first threshold, submitting PDCP data units only to the first RLC entity.
6. The method according to claim 1 , wherein the first uplink transmission path is associated with the first RLC entity, and wherein the second uplink transmission path is associated with the second RLC entity.
7. A user equipment (UE) configured to transmit packet data units (PDUs) by a first Radio Link Control (RLC) entity and/or by a second RLC entity, the UE comprising:
transceiver circuitry configured to send and receive radio signals; and
processing circuitry operatively associated with the transceiver circuitry and configured to:
determine a total amount of data volume pending for transmission, wherein the total amount of data volume comprises Packet Data Convergence Protocol (PDCP) data volume buffered for transmission and RLC data volume pending for initial transmission in the two RLC entities; and
indicate the PDCP data volume to at least a first uplink transmission path, based on whether the total amount of data volume meets or exceeds a first threshold, wherein the indicating comprises:
in response to determining that the total amount of data volume meets or exceeds the first threshold, indicating the PDCP data volume to both the first uplink transmission path and a second uplink transmission path, and
in response to determining that the total amount of data volume does not meet the first threshold, indicating the PDCP data volume to only the first uplink transmission path.
8. The UE according to claim 7 , wherein:
the PDCP data volume comprises PDCP service data unit (SDU) and PDU data volume buffered for transmission; and
the RLC data volume comprises RLC SDU and PDU data volume pending for initial transmission.
9. The UE according to claim 7 , wherein the first uplink transmission path is a prioritized uplink transmission path and the second uplink transmission path is an unprioritized uplink transmission path.
10. The UE according to claim 7 , wherein the first RLC entity belongs to a Master Cell Group (MCG) and the second RLC entity belongs to a Secondary Cell Group (SCG).
11. The UE according to claim 7 , wherein the processing circuitry is configured to, in response to determining that the total amount of data does not meet the first threshold, submit PDCP data units only to the first RLC entity.
12. The UE according to claim 7 , wherein the first uplink transmission path is associated with the first RLC entity, and wherein the second uplink transmission path is associated with the second RLC entity.