Method of generating protocol data units in split mode

A method of generating protocol data units (PDU) in a system having a radio link control (RLC) layer, a media access control (MAC) layer, and a physical (PHY) layer, the method comprising the steps of:

• (a) producing a payload unit by segmenting or concatenating one or more service data units transmitted from a higher layer;
• (b) generating a first PDU which includes a sequence number corresponding to said payload unit and a second PDU which includes said payload unit;
• (c) transmitting said first and second PDUs to said MAC layer;
• (d) generating a first transport block by attaching a MAC header to said first PDU and a second transport block by attaching said MAC header to said second PDU;
• (e) transmitting said first and second transport blocks to aid PHY layer;
• and
• (g) transmitting said first and second transport blocks to a receiving system after attaching a cyclic redundancy check to each of said first and second transport blocks.