Configuration of HS-DSCH serving cell change improvements
A cell change procedure for user equipment (UE) situated in a serving cell. An active set of cells comprises a list of cells to which the UE can move from the serving cell. The UE sends a request to a network controller to add at least one further cell to the active set. The UE then receives the requested active set update from the network controller with the further cell and a list of cells to which a modified cell change procedure shall be used for handover. A neighbor cell which is stronger than a current serving cell is detected. This detected stronger neighbor cell is matching with the received list of modified cell change procedure cells, and the modified cell change procedure for the handover to the stronger neighbor cell is applied if the stronger neighbor cell is found matching a cell on the list.
1. A method in a user equipment for configuring a cell change procedure to be used for handover in a wireless communication network, the user equipment being situated in a serving cell and utilizing a list of cells belonging to an active set, said list including cells to which the user equipment can move from the serving cell, the method comprising:
sending a measurement report to a network controller in the wireless communication network that informs the network controller to add at least one further cell to the active set;
receiving, responsive to said measurement report, an active set update from the network controller, the active set update comprising information about the at least one further cell to be added to the active set and an information element indicating whether the at least one further cell is to be added to a list of cells for which a modified cell change procedure shall be used for hand over;
detecting a neighbor cell which is stronger than the serving cell;
determining whether the neighbor cell matches a cell in the list of cells for which the modified cell change procedure shall be used; and
applying the modified cell change procedure for handover to the neighbor cell if the neighbor cell matches a cell on that list.
2. A method according to claim 1 , wherein the method further comprises applying a regular cell change procedure for the handover if the neighbor cell does not match a cell on said list of cells for which a modified cell change procedure shall be used.
3. A method according to claim 1 , wherein the modified cell change procedure comprises sending a cell change command over the neighbor cell.
4. A method according to claim 1 , wherein the active set update message is transmitted via radio resource control signaling.
5. A method according to claim 1 , wherein the cells to which a modified cell change procedure is applied is signaled by including an information element “Target cell preconfiguration information” to the corresponding “Radio link addition information”.
6. A method according to claim 1 , wherein detecting a neighbor cell which is stronger than the serving cell comprises measuring a higher signal strength in the neighbor cell compared to that of the current serving cell.
7. A method according to claim 6 , where the measured signal is a common pilot.
8. A method according to claim 1 , wherein the cell change procedure is a high speed serving cell change procedure.
9. A method in a network controller for configuring a cell change procedure to be used for handover in a wireless communication network, the network controller arranged to be connected to a user equipment situated in a serving cell, and the user equipment utilizing a list of cells belonging to an active set, said list including cells to which the user equipment can move from the serving cell, the method comprising:
receiving a measurement report from a user equipment informing the network controller to add at least one further cell to an active set; and
sending an active set update to the user equipment, the active set update comprising information about the at least one further cell to be added to the active set and an information element indicating whether the at least one further cell is to be added to a list of cells for which a modified cell change procedure shall be used for handover.
10. A method according to claim 9 , wherein the cell change procedure is a high speed serving cell change procedure.
11. A user equipment in a wireless communication network adapted to configure a cell change procedure to be used for handover in the network, the user equipment utilizing a list of cells belonging to an active set, said list including cells to which the user equipment can move from the serving cell, the user equipment comprising:
a sender configured to send a measurement report to a network controller through an interface informing the network controller to add at least one further cell to the active set;
a receiver configured to receive an active set update from the network controller, the active set update comprising information about the at least one further cell to be added to the active set and an information element indicating whether the at least one further cell is to be added to a list of cells for which a modified cell change procedure shall be used for handover;
a detector configured to detect a neighbor cell which is stronger than a serving cell in which the user equipment is situated; and
a processor configured to determine whether the neighbor cell matches a cell in the list of cells for which the modified cell change procedure shall be used, and to apply the modified cell change procedure for handover to the neighbor cell if the neighbor cell matches a cell on that list.
12. A user equipment according to claim 11 , wherein the processor is further configured to apply a regular cell change procedure for the handover if the neighbor cell does not match a cell on said list of cells for which a modified cell change procedure shall be used.
13. A user equipment according to claim 11 , wherein the modified cell change procedure comprises sending a cell change command over the neighbor cell.
14. A user equipment according to claim 11 , wherein the active set update message is transmitted via radio resource control signaling.
15. A user equipment according to claim 11 , wherein the cells to which a modified cell change procedure is applied is signaled by including an information element “Target cell preconfiguration information” to the corresponding “Radio link addition information”.
16. A user equipment according to claim 11 , wherein the detector is configured to detect a neighbor cell which is stronger than the serving cell by measuring a higher signal strength in the neighbor cell compared to that of the serving cell.
17. A user equipment according to claim 16 , where the measured signal is a common pilot.
18. A user equipment according to claim 11 , wherein the cell change procedure is a high speed serving cell change procedure.
19. A network controller in a wireless communication network adapted to configure a cell change procedure to be used for handover in the network, the network controller also adapted to connect to a user equipment situated in a serving cell, the user equipment utilizing a list of cells belonging to an active set, said list including cells to which the user equipment can move from the serving cell, the network controller comprising
a receiver configured to receive a measurement report from the user equipment informing the network controller to add at least one further cell to an active set; and
a sender configured to send an active set update to the user equipment, the active set update comprising information about the at least one further cell to be added to the active set and an information element indicating whether the at least one further cell is to be added to a list of cells for which a modified cell change procedure shall be used for handover.
20. The network controller according to claim 19 , wherein the cell change procedure is a high speed serving cell change procedure.
21. A computer program product stored in a non-transitory computer-readable memory and comprising a stored computer program for use in a node in a wireless communication network, the program being arranged to configure a cell change procedure to be used for handover in the wireless communication network, the program comprising instruction sets for:
sending a measurement report that informs a network controller in the network to add at least one further cell to an active set;
receiving an active set update from the network controller, the active set update comprising information about the at least one further cell to be added to the active set and an information element indicating whether the at least one further cell is to be added to a list of cells for which a modified cell change procedure shall be used for handover;
detecting a neighbor cell which is stronger than a serving cell in which the node is situated;
determining whether the neighbor cell matches a cell in the list of cells for which a modified cell change procedure shall be used; and for
applying the modified cell change procedure for hand over to the neighbor cell if the neighbor cell matches a cell on that list.