Method and apparatus for handling soft buffer size with dual connectivity in wireless communication system

A user equipment (UE) configured to operate in a wireless communication system, wherein the UE is configured to be connected to both a first system and a second system in dual connectivity, the UE comprising:

• a memory;
• a transceiver;
• and
• a processor, operably coupled to the memory and the transceiver, that is configured to perform operations comprising:
• determining a first UE capability for the first system and a second UE capability for the second system;
• determining a total soft buffer size based on the first UE capability and the second UE capability;
• and
• sharing the total soft buffer size between the first system and the second system based on at least one of a maximum transport block size (TBS) per transmission time interval (TTI) and a number of carriers used in the second system,
• wherein the maximum TBS per TTI is defined per bandwidth part (BWP).