Enhanced uplink operation in soft handover
A method and system for an enhanced uplink (EU) operation in a wireless communication system during soft handover. The system comprises a wireless transmit/receive unit (WTRU), at least two Node-Bs, and a radio network controller (RNC). One Node-B may be designated as a primary Node-B, and the primary Node-B may control EU operation during soft handover including uplink scheduling and hybrid automatic repeat request (H-ARQ). Soft buffer corruption is avoided during soft handover by controlling H-ARQ by the primary Node-B. Alternatively, an RNC may control EU operation during soft handover including H-ARQ. In this case, an RNC generates final acknowledge/non-acknowledge (ACK/NACK) decision based on the error check results of the Node-Bs.
1. A wireless transmit/receive unit (WTRU) comprising:
a wireless transceiver; and
a processor,
wherein the processor causes the WTRU during a softer handover procedure to:
communicate, using the wireless transceiver, via a primary cell and a non-primary cell, wherein both of the primary cell and the non-primary cell are controlled by a Node-B;
receive, using the wireless transceiver, a message via the primary cell and not via the non-primary cell, wherein the received message includes information identifying a shared downlink data channel of the non-primary cell;
read the received message including the information identifying the shared downlink data channel of the non-primary cell; and
receive, using the wireless transceiver, downlink data over the identified shared downlink data channel.
2. The WTRU of claim 1 , wherein the information identifying the shared downlink data channel is control information included in the received message, and wherein the received message is received over a shared downlink control channel via the primary cell and not via the non-primary cell.
3. The WTRU of claim 2 , wherein the identified shared downlink control channel is one of a plurality of shared downlink control channels of the primary cell.
4. The WTRU of claim 2 , wherein the processor further causes the WTRU to read the control information.
5. The WTRU of claim 1 , wherein the received message further includes information identifying a plurality of shared downlink data channels of the non-primary cell.
6. The WTRU of claim 5 , wherein the WTRU receives, using the wireless transceiver, downlink data over each of the identified plurality of shared downlink data channels.
7. A method comprising:
communicating, using a wireless transmit/receive unit (WTRU) during a softer handover, via a primary cell and a non-primary cell, wherein both of the primary cell and the non-primary cell are controlled by a Node-B;
receiving, using the wireless transceiver, a message via the primary cell and not via the non-primary cell, wherein the received message includes information identifying a shared downlink data channel of the non-primary cell;
reading, by the WTRU, the received message including the information identifying the shared downlink data channel of the non-primary cell; and
receiving, by the WTRU, downlink data over the identified shared downlink data channel.
8. A method comprising:
communicating, using a wireless transmit/receive unit (WTRU) during a softer handover procedure, via a primary cell and a non-primary cell, wherein both of the primary cell and the non-primary cell are controlled by a Node-B;
receiving, using the wireless transceiver, a message via the primary cell and not via the non-primary cell, wherein the received message includes information identifying a shared downlink data channel of the non-primary cell;
reading, by the WTRU, the received message including the information identifying the shared downlink data channel of the non-primary cell; and
receiving, by the WTRU, downlink data over the identified shared downlink data channel.
9. The method of claim 8 , further comprising:
receiving, by the WTRU, the control information over one of a plurality of shared downlink control channels of the primary cell.
10. The method of claim 8 , further comprising:
reading the control information.
11. The method of claim 7 , wherein the received message further includes information identifying a plurality of shared downlink data channels of the non-primary cell.
12. The method of claim 11 , wherein the downlink data is received via each of the identified plurality of shared downlink data channels.
13. A wireless transmit/receive unit (WTRU) comprising:
a wireless transceiver; and
a processor,
wherein the processor causes the WTRU during a softer handover to:
communicate, using the wireless transceiver, via a primary cell and a plurality of non-primary cells, wherein both of the primary cell and the plurality of non-primary cells are controlled by a Node-B;
receive, using the wireless transceiver, a message via the primary cell and not via any of the plurality of non-primary cell, wherein the received message includes information identifying a shared downlink data channel of the non-primary cell;
read the received message including the information identifying the shared downlink data channel of a corresponding one of the non-primary cells; and
receive, using the wireless transceiver, downlink data over the identified shared downlink data channel.
14. The WTRU of claim 13 , wherein the information identifying the shared downlink data channel is control information included in the received message, and wherein the received message is received over a shared downlink control channel via the primary cell and not via any of the plurality of non-primary cells.
15. A wireless transmit/receive unit (WTRU) comprising:
a wireless transceiver; and
a processor,
wherein the processor causes the WTRU during a softer handover procedure to:
communicate, using the wireless transceiver, via a primary cell and a plurality of non-primary cells, wherein both of the primary cell and the plurality of non-primary cells are controlled by a Node-B;
receive, using the wireless transceiver, a message via the primary cell and not via any of the plurality of non-primary cell, wherein the received message includes information identifying a shared downlink data channel of the non-primary cell;
read the received message including the information identifying the shared downlink data channel of a corresponding one of the non-primary cells; and
receive, using the wireless transceiver, downlink data over the identified shared downlink data channel.
16. The WTRU of claim 14 , wherein the processor further causes the WTRU to read the control information.
17. The WTRU of claim 13 , wherein the received message further includes information identifying a plurality of shared data downlink channels of corresponding ones of the plurality of non-primary cells.
18. The WTRU of claim 17 , wherein the WTRU receives, using the wireless transceiver, downlink data over each of the identified plurality of downlink data channels.
19. A method comprising:
communicating, by a wireless transmit/receive unit (WTRU) during a softer handover, via a primary cell and a plurality of non-primary cells, wherein both of the primary cell and the plurality of non-primary cell are controlled by a first Node-B;
receiving, using the wireless transceiver, a message via the primary cell and not via any of the plurality of non-primary cell, wherein the received message includes information identifying a shared downlink data channel of the non-primary cell;
reading, by the WTRU, the received message including the information identifying the shared downlink data channel of a corresponding one of the plurality of non-primary cells; and
receiving, by the WTRU, information over the downlink data shared downlink data channel.
20. The method of claim 19 , wherein the information identifying the shared downlink data channel is control information included in the received message, and wherein the received message is received over a shared downlink control channel via the primary cell and not via any of the plurality of non-primary cells.
21. The method of claim 20 , further comprising:
receiving, by the WTRU, the control information over a plurality of shared downlink control channels of the primary cell.
22. The method of claim 20 , further comprising:
reading the control information.
23. A method comprising:
communicating, by a wireless transmit/receive unit (WTRU) during a softer handover procedure, via a primary cell and a plurality of non-primary cells, wherein both of the primary cell and the plurality of non-primary cell are controlled by a Node-B;
receiving, using the wireless transceiver, a message via the primary cell and not via any of the plurality of non-primary cell, wherein the received message includes information identifying a shared downlink data channel of the non-primary cell;
reading, by the WTRU, the received message including the information identifying the shared downlink data channel of a corresponding one of the plurality of non-primary cells; and
receiving, by the WTRU, information over the downlink data shared downlink data channel.
24. The method of claim 23 , wherein the WTRU receives the downlink data via each of the identified plurality of downlink data channels.