Method and apparatus for cell update while in an enhanced Cell
A method and apparatus for cell update while in a Cell_FACH state are disclosed. After selecting a target cell, system information is read from the target cell including high speed downlink shared channel (HS-DSCH) common system information. A radio network temporary identity (RNTI) received in a source cell is cleared and a variable HS_DSCH_RECEPTION is set to TRUE. An HS-DSCH medium access control (MAC-hs) entity is configured based on the HS-DSCH common system information. High speed downlink packet access (HSDPA) transmission is then received in the target cell. A CELL UPDATE message is sent to notify of a cell change. The HSDPA transmission may be received using a common H-RNTI broadcast in the system information, a reserved H-RNTI as requested in a CELL UPDATE message, or a temporary identity which is a subset of a U-RNTI. The MAC-hs entity may be reset.
1. A method for performing cell reselection while in a Cell_FACH state, the method comprising:
initiating a cell update procedure with cause cell reselection while in the Cell_FACH state;
receiving system information including high speed downlink shared channel (HS-DSCH) common system information;
clearing a cell radio network temporary identity (C-RNTI);
clearing an HS-DSCH radio network temporary identity (H-RNTI);
resetting an HS-DSCH medium access control (MAC-ehs) entity; and
receiving a high speed downlink packet access (HSDPA) transmission using a common H-RNTI.
2. The method of claim 1 , wherein the common H-RNTI is selected following receipt of a CELL UPDATE CONFIRM RRC message.
3. The method of claim 1 , further comprising enabling HS-DSCH reception by setting an HS-DSCH reception variable to TRUE.
4. The method of claim 3 , wherein the common H-RNTI is selected when the HS-DSCH reception variable is set to TRUE.
5. The method of claim 3 , wherein the HS-DSCH reception variable is an HS_DSCH_RECEPTION_OF_CCCH_ENABLED variable.
6. The method of claim 1 , wherein a universal terrestrial radio access network (UTRAN) radio network temporary identity (U-RNTI) is assigned for DCCH transmissions.
7. The method of claim 6 , wherein the U-RNTI is included as a MAC-c header.
8. The method of claim 7 , wherein the U-RNTI is an identity of a wireless transmit receive unit (WTRU) in the MAC-c header.
9. The method of claim 1 , wherein the MAC-ehs entity is reset for both a common H-RNTI and a dedicated H-RNTI, if the common H-RNTI and the dedicated H-RNTI are configured with separate MAC-ehs entities.
10. The method of claim 1 , wherein the MAC-ehs entity is reset when cell reselection results in an inter-Node B cell change.
11. The method of claim 1 , further comprising sending a radio link control (RLC) status report upon cell reselection.
12. The method of claim 1 , further comprising stopping using the C-RNTI and the H-RNTI just cleared.
13. A wireless transmit receive unit (WTRU) for performing cell reselection while in a Cell_FACH state, the WTRU comprising:
a controller configured to, while in the Cell_FACH state, initiate a cell update procedure with cause cell reselection, receive system information including high speed downlink shared channel (HS-DSCH) common system information, clear a cell radio network temporary identity (C-RNTI), clear an HS-DSCH radio network temporary identity (H-RNTI), reset an HS-DSCH medium access control (MAC-ehs) entity, and receive a high speed downlink packet access (HSDPA) transmission using a common H-RNTI.
14. The WTRU of claim 13 , wherein the common H-RNTI is selected following receipt of a CELL UPDATE CONFIRM RRC message.
15. The WTRU of claim 13 , further comprising enabling HS-DSCH reception by setting an HS-DSCH reception variable to TRUE.
16. The WTRU of claim 15 , wherein the common H-RNTI is selected when the HS-DSCH reception variable is set to TRUE.
17. The WTRU of claim 15 , wherein the HS-DSCH reception variable is an HS_DSCH_RECEPTION_OF_CCCH_ENABLED variable.
18. The WTRU of claim 13 , wherein a universal terrestrial radio access network (UTRAN) radio network temporary identity (U-RNTI) is assigned for DCCH transmissions.
19. The WTRU of claim 18 , wherein the U-RNTI is included as a MAC-c header.
20. The WTRU of claim 19 , wherein the U-RNTI is an identity of the WTRU in the MAC-c header.
21. The WTRU of claim 13 , wherein the MAC-ehs entity is reset for both a common H-RNTI and a dedicated H-RNTI, if the common H-RNTI and the dedicated H-RNTI are configured with separate MAC-ehs entities.
22. The WTRU of claim 13 , wherein the MAC-ehs entity is reset when cell reselection results in an inter-Node B cell change.
23. The WTRU of claim 13 , further comprising sending a radio link control (RLC) status report upon cell reselection.
24. The WTRU of claim 13 , further comprising stopping using the C-RNTI and the H-RNTI just cleared.