Supporting enhanced uplink transmission during soft handover

A wireless transmit/receive unit (WTRU), comprising:

• a transmitter;
• and
• a receiver,
• wherein when the WTRU is in a handover from a primary cell to a non-primary cell,
• the receiver receives scheduling information via the primary cell and not via the non-primary cell,
• the transmitter transmits, via the primary cell and the non-primary cell, enhanced uplink (EU) data according to the scheduling information to control interference at the primary cell and at the non-primary cell,
• the receiver receives hybrid automatic repeat request (HARQ) acknowledgements (ACKs) via the primary cell, and
• the receiver receives negative acknowledgements (NACKs) via the primary cell and not via the non-primary cell.

A wireless network comprising a plurality of Node-Bs configured to communicate with a wireless transmit/receiver unit (WTRU) during a handover from a first Node-B of the plurality of Node-Bs to a second Node-B of the plurality of Node-Bs by:

• transmitting scheduling information to the WTRU via the first Node-B;
• receiving enhanced uplink (EU) data from the WTRU via the first Node-B and the second Node-B according to the scheduling information to control interference at the first Node-B and at the second Node-B;
• transmitting hybrid automatic repeat request (HARQ) acknowledgements (ACKs) to the WTRU via the first Node-B;
• and
• transmitting negative acknowledgements (NACKs) to the WTRU via the first Node-B and not via the second Node-B.

A Node B comprising:

• at least one transceiver;
• and
• a processor;
• wherein, when the Node B is performing an intra-Node B handover for a wireless transmit/receive unit (WTRU) from a primary cell to a non-primary cell, the processor causes the at least one transceiver to:
• transmit, via the primary cell and not via the non-primary cell, scheduling information to the WTRU to schedule enhanced uplink (EU) data transmissions from the WTRU,
• receive, via the primary cell and the non-primary cell, EU data transmissions from the WTRU, wherein the EU data transmission from the WTRU are transmitted according to the scheduling information,
• transmit, via the primary cell, hybrid automatic repeat request (HARQ) acknowledgements (ACKs) to the WTRU, and
• transmit, via the primary cell but not via the non-primary cell, negative acknowledgements (NACKs) to the WTRU.

A wireless transmit/receive unit (WTRU), comprising:

• a transmitter;
• and
• a receiver,
• wherein when the WTRU is in a handover from a primary cell to a non-primary cell, the primary cell and the non-primary cell being associated with a Node-B,
• the receiver receives from the Node-B, via the primary cell and not via the non-primary cell, scheduling information,
• the transmitter transmits to the Node-B, via the primary cell and the non-primary cell, enhanced uplink (EU) data according to the scheduling information,
• the receiver receives from the Node-B, via the primary cell, hybrid automatic repeat request (HARQ) acknowledgements (ACKs), and
• the receiver receives from the Node-B, via the primary cell but not via the non-primary cell, negative acknowledgements (NACKs).

A wireless communication system comprising:

• a wireless transmit/receiver unit (WTRU);
• and
• a wireless network including a primary cell and a non-primary cell, the primary cell and the non-primary cell being associated with a Node-B,
• wherein, during a handover from the primary cell to the non-primary cell,
• the Node-B is configured to transmit scheduling information to the WTRU via the primary cell and not via the non-primary cell to schedule enhanced uplink (EU) data transmissions from the WTRU,
• the WTRU is configured to transmit EU data transmissions to the Node-B via the primary cell and the non-primary cell,
• the Node-B is configured to receive, via the primary cell and the non-primary cell, EU data transmissions from the WTRU according to the scheduling information,
• the Node-B is configured to transmit hybrid automatic repeat request (HARQ) acknowledgements (ACKs) via the primary cell, and
• the Node-B is configured to transmit negative acknowledgements (NACKs) via the primary cell and to not transmit the NACKs via the non-primary cell.