Method for handoff during connected mode of a multimode mobile station in a mixed deployment

• US 20100002653A1
• Filed: 07/07/2009
• Published: 01/07/2010
• Est. Priority Date: 07/07/2008
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Nigam, Arishuman, Agiwal, Anil, Vadlapudi, Tirumala Sree Hari Vara Prasad
• Granted Patent: US 9,173,138 B2
• Time in Patent Office: Days
• US Class Current: 370/331
• CPC Class Codes: H04W 36/0061 of neighbour cell information
• CPC Class Codes: H04W 36/08 Reselecting an access point
• CPC Class Codes: H04W 36/14 Reselecting a network or an air interface

Abstract

Methods for handoff of a multimode mobile station (MS). The MS, in connected mode, moves from a cell of a legacy base station to a cell of an ABS and scans base stations from a list of neighbouring base stations, wherein at least the ABS is listed as another legacy base station in the list of neighbouring base stations. The MS performs the handoff to connect to a legacy zone of the ABS. Further, the multimode MS switching from the legacy zone of the ABS to a advanced zone of the ABS based on a Zone Switch request or command is triggered by either the multimode MS or the ABS. The Zone Switch request is triggered after detecting capabilities of either the multimode MS or the ABS that they support advanced zone. The capabilities are detected by using MAC versions of the multimode MS and the ABS or an indicator for the advanced zone. The multimode MS can also performs handoff to the advanced zone from the cell of the legacy base station by receiving one or more information for ranging in the advanced zone from the ABS during the handoff.

Claims

1. A method for handoff of a multimode mobile station when the multimode mobile stationis moving from a cell of a first legacy base station to a neighbouring cell of an advanced base station (ABS), wherein the ABS including a legacy zone and a advanced zone, the method comprising:

scanning, by the multimode mobile station, a plurality of base stations from a list of neighbouring base stations, wherein the plurality of base stations includes at least the ABS; and

performing, by the multimode mobile station, the handoff from the first legacy base station to the legacy zone of the ABS.

2. The method according to claim 1, wherein scanning, by the multimode mobile station, the plurality of base stations from the list of neighbouring base stations comprises:

receiving, by the multimode mobile station, the list of neighbouring base stations from the first legacy base station through a neighbour advertisement message.

3. The method according to claim 1 further comprising:

triggering, by one of;

the multimode mobile station and the ABS, a Zone Switch request for switching of the multimode mobile station from the legacy zone of the ABS to the advanced zone of the ABS.

4. The method according to claim 3, wherein triggering the Zone Switch request by the multimode mobile station comprises:

detecting, by the multimode mobile station, a capability of the ABS, by using one of;

a MAC version of the ABS, and

an indicator for the advanced zone, wherein the capability of the ABS is to support the advanced zone; and

transmitting, by the multimode mobile station, the Zone Switch request to the ABS, based on the capability of the ABS.

5. The method according to claim 4, wherein detecting, by the multimode mobile station, the capability of the ABS by using the MAC version of the ABS comprises:

receiving, by the multimode mobile station, the MAC version of the ABS though a broadcast message from one of;

the legacy zone of the ABS; and

the first legacy base station, wherein the MAC version of the ABS indicates the capability of the ABS to support the advanced zone.

6. The method according to claim 5, wherein receiving, by the multimode mobile station, the MAC version of the ABS through an overhead message from the legacy zone of the ABS.

7. The method according to claim 5, wherein receiving, by the multimode mobile station, the MAC version of the ABS through a neighbor advertisement message from one of:

the legacy zone of the ABS, and

the first legacy base station.

8. The method according to claim 4, wherein detecting, by the multimode mobile station, the capability of the ABS by using the indicator for the advanced zone comprises:

receiving, by the multimode mobile station, the indicator for the advanced zone from the legacy zone of the ABS through a downlink parameter broadcast in FCH.

9. The method according to claim 4, wherein transmitting, by the multimode mobile station, the Zone Switch request to the ABS using a ranging request (RNG REQ) message.

10. The method according to claim 9, wherein transmitting, by the multimode mobile station, the Zone Switch request to the ABS by setting a ranging purpose indicator in the RNG REQ message to Zone Switch request.

11. The method according to claim 4 further comprising:

receiving, by the multimode mobile station, a response message to the Zone Switch request from the ABS; and

switching, by the multimode mobile station, to the advanced zone of the ABS from the legacy zone of the ABS, based on the response message received from the ABS.

12. The method according to claim 11, wherein switching, by the multimode mobile station, to the advanced zone of the ABS from the legacy zone of the ABS, by using at least one information when the response message includes the one or more information for the switching, wherein the response message includes at least one of:

a frame offset, and

a preamble information

13. The method according to claim 3, wherein triggering the Zone Switch request by the ABS comprises:

detecting, by the ABS, a capability of the multimode mobile station, by using a MAC version of the multimode mobile station, wherein the capability of the multimode mobile station is to support the advanced zone; and

transmitting, by the ABS, a Zone Switch command to the multimode mobile station, based on the capability of the multimode mobile station, wherein the Zone Switch command includes one or more information for the switching.

14. The method according to claim 13, wherein detecting, by the ABS, the multimode mobile station comprises:

receiving, by the ABS, the MAC version of the multimode mobile station from one of;

the first legacy base station, wherein the MAC version of the multimode mobile station is received over a backhaul network, and

the multimode mobile station, wherein the MAC version of the multimode mobile station is received through a signaling message from the multimode mobile station.

15. The method according to claim 13, wherein transmitting, by the ABS, the Zone Switch command to the multimode mobile station by using one of:

a command signaling message, and

a ranging response (RNG RSP) message.

16. The method according to claim 15, wherein transmitting, by the ABS, the Zone Switch command, by using the RNG RSP message when the ABS receives a ranging request (RNG REQ) message from the multimode mobile station.

17. The method according to claim 13 further comprising:

receiving, by the multimode mobile station, the Zone Switch command from the ABS; and

switching, by the multimode mobile station, to the advanced zone of the ABS from the legacy zone of the ABS, using the one or more information for the switching received from the ABS, wherein the response message includes at least one of;

a frame offset, and

a preamble information.

18. A method for handoff of a multimode mobile station when the multimode mobile stationis moving from a cell of a first legacy base station to a neighbouring cell of an advanced base station (ABS), wherein the ABS is having a legacy zone and a advanced zone, the method comprising:

scanning, by the multimode mobile station, a plurality of base stations from a list of neighbouring base stations, wherein the plurality of base stations includes at least the ABS;

indicating, by the multimode mobile station, a capability of the multimode mobile station to the first legacy base station, by using a MAC version of the multimode mobile station, wherein the capability of the multimode mobile station is to support the advanced zone;

performing, by the multimode mobile station, a handoff into the legacy zone of the ABS; and

detecting, by the multimode mobile station, a capability of the ABS, by using one of;

a MAC version of the ABS,

an indicator for the advanced zone, wherein the capability of the ABS is to support the advanced zone; and

switching, by the multimode mobile station, from the legacy zone to the advanced zone by using one or more information for ranging in the advanced zone, based on the capability of the ABS.

19. The method according to claim 18, wherein scanning, by the multimode mobile station, the plurality of base stations from the list of neighbouring base stations comprises:

receiving, by the multimode mobile station, the list of neighbouring base stations from the first legacy base station through a neighbour advertisement message.

20. The method according to claim 18, wherein performing, by the multimode mobile station, the handoff into the legacy zone comprises:

transmitting, by the multimode mobile station, a handoff request to the first legacy base station;

receiving, a response to the handoff request from the first legacy base station, wherein the response includes the one or more information for ranging in the advanced zone of the ABS based on the capability of the multimode mobile station;

synchronizing, by the multimode mobile station, to the legacy zone of the ABS.

21. The method according to claim 20, wherein synchronizing, by the multimode mobile station, to the legacy zone of the ABS comprises:

obtaining, by the multimode mobile station, one or more downlink and uplink parameters of the legacy zone through a broadcast message from the legacy zone.

22. The method according to claim 18, wherein detecting, by the multimode mobile station, the capability of the ABS by using the MAC version of the ABS comprises:

receiving, by the multimode mobile station, the MAC version of the ABS though a broadcast message from one of;

the legacy zone of the ABS, and

the first legacy base station, wherein the MAC version of the ABS indicates the capability of the ABS.

23. The method according to claim 22, wherein receiving, by the multimode mobile station, the MAC version of the ABS through an overhead message from the legacy zone of the ABS.

24. The method according to claim 22, wherein receiving, by the multimode mobile station, the MAC version of the ABS through a neighbour advertisement message from one of:

the legacy zone of the ABS, and

the first legacy base station.

25. The method according to claim 18, wherein detecting, by the multimode mobile station, the capability of the ABS by using the indicator for the advanced zone comprises:

receiving, by the multimode mobile station, the indicator for the advanced zone from the legacy zone of the ABS through a downlink parameter broadcast in FCH.

26. A method for handoff of a multimode mobile station when the multimode mobile stationis moving from a cell of a legacy base station to a neighbouring cell of an advanced base station (ABS), wherein the ABS is having a legacy zone and a advanced zone, the method comprising:

receiving, by the ABS, a MAC version of the multimode mobile station from the legacy base station, wherein the MAC version of the multimode mobile station indicates a capability of the multimode mobile station, wherein the capability of the multimode mobile station is to support the 16m zone;

receiving, by the ABS, a handoff request from the legacy base station;

broadcasting, by the ABS, a MAC version of the ABS to the legacy base station and the legacy zone; and

transmitting, by the ABS, a response message to the handoff request to the legacy base station, wherein the response message includes at least a ranging resource for ranging of the multimode mobile station in the advanced zone when the ABS detects the capability of the multimode mobile station.