Method and apparatus for facilitating a hand-in of user equipment to femto cells

• US 9,204,349 B2
• Filed: 02/09/2010
• Issued: 12/01/2015
• Est. Priority Date: 02/10/2009
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Nagaraja, Sumeeth, Yavuz, Mehmet, Radulescu, Andrei D., Singh, Damanjit, Chen, Jen M., Rauber, Peter H., Gholmieh, Aziz, Nanda, Sanjiv, Zhao, Lijun
• Primary Examiner(s): Shen, Qun
• Application Number:
  US12/703,065
• Publication Number:
  US 20100203891A1
• Time in Patent Office: 2,121 Days
• Field of Search: 455/435.1, 455/435.2, 455/436, 455/444, 370/331
• US Class Current: 1/1
• CPC Class Codes: H04W 28/18 Negotiating wireless communication parameters
• CPC Class Codes: H04W 36/0055 Transmission or use of information for re-establishing the radio link
• CPC Class Codes: H04W 36/0061 of neighbour cell information
• CPC Class Codes: H04W 36/08 Reselecting an access point
• CPC Class Codes: H04W 36/26 by agreed or negotiated communication parameters
• CPC Class Codes: H04W 8/26 Network addressing or numbering for mobility support
• CPC Class Codes: H04W 84/045 using private Base Stations, e.g. femto Base Stations, home Node B

Abstract

Aspects are disclosed for facilitating a hand-in to a femto cell. An identifier is assigned to a femto cell in which the identifier is based on a scrambling parameter and a timing parameter. A relationship between the identifier and the femto cell is then communicated. In another embodiment, a user equipment report is received, which includes attributes related to a signal broadcast by a femto cell. An identifier associated with the femto cell is ascertained from an attribute included in the report. The femto cell is then identified based on the identifier. In a further embodiment, a timing parameter is received, and a scrambling parameter is set. A signal including the scrambling parameter is then broadcast according to an offset related to the timing parameter. In yet another embodiment, a femto cell is detected during an active call. An identifier associated with the femto cell is then ascertained and reported.

Claims

1. A method that facilitates a hand-in of a user equipment to a femto cell, comprising:

identifying, by a network entity, a macro node assigned for the femto cell;

assigning, by the network entity, a unique identifier to the femto cell, wherein the unique identifier is taken from a Cartesian product of a set of primary scrambling codes and a set of offset values, and the set of offset values is related to a timing parameter including a first system frame number of the macro node; and

transmitting an assignment of the unique identifier and the femto cell and the timing parameter to the femto cell for determining a second system frame number of the femto cell based on the first system frame number of the macro node and an offset value in the unique identifier, wherein the first and second system frame numbers are configured to synchronize with each other based on a periodic increment of the first system frame number received by the femto cell via a downlink channel to avoid time drifts, the periodic increment of the first system frame number is configured to be broadcast through a transport channel, and the transport channel is configured to be mapped to the downlink channel.

2. The method of claim 1, wherein the transmitting includes transmitting the relationship to an external entity.

3. The method of claim 1, wherein the transmitting includes transmitting the relationship to the femto cell.

4. The method of claim 1, further comprising ascertaining a primary scrambling code corresponding to the macro node.

5. The method of claim 4, wherein the ascertaining includes receiving a selection of at least one candidate primary scrambling code from the femto cell, the primary scrambling code being ascertained from the selection.

6. The method of claim 5, wherein the primary scrambling code ascertained from auxiliary macro cell information includes at least one of a path loss of a wireless channel between a pair of neighboring cells, a quality of a macro cell pilot signal, or a strength of a macro cell signal.

7. The method of claim 1, wherein the unique identifier is unique with respect to a localized area relative to the macro node associated with the femto cell.

8. An apparatus of a network entity that facilitates a hand-in of a user equipment to a femto cell, the apparatus comprising:

a processor configured to execute computer executable components stored in memory, the components including;

an identification component configured to identify a macro node assigned for the femto cell;

an assignment component configured to assign a unique identifier to the femto cell, wherein the unique identifier is taken from a Cartesian product of a set of primary scrambling codes and a set of offset values, and the set of offset values is related to a timing parameter including a first system frame number of the macro node; and

a transmitting component configured to transmit an assignment of the unique identifier and the femto cell and the timing parameter to the femto cell for determining a second system frame number of the femto cell based on the first system frame number of the macro node and an offset value in the unique identifier, wherein the first and second system frame numbers are configured to synchronize with each other based on a periodic increment of the first system frame number received by the femto cell via a downlink channel to avoid time drifts, the periodic increment of the first system frame number is configured to be broadcast through a transport channel, and the transport channel is configured to be mapped to the downlink channel.

9. The apparatus of claim 8, wherein the transmitting component is configured to transmit the relationship to an external entity.

10. The apparatus of claim 8, wherein the transmitting component is configured to transmit the relationship to the femto cell.

11. The apparatus of claim 8, further comprising a code component configured to ascertain a primary scrambling code corresponding to the macro node.

12. The apparatus of claim 11, further comprising a receiving component configured to receive a selection of at least one candidate primary scrambling code from the femto cell.

13. A non-transitory computer-readable storage medium embedded thereon a computer executable program comprising code for facilitating a hand-in of a user equipment to a femto cell, the code causing at least one computer of a network entity to:

identify a macro node assigned to the femto cell;

assign a unique identifier to the femto cell, wherein the unique identifier is taken from a Cartesian product of a set of primary scrambling codes and a set of offset values, and the set of offset values is related to a timing parameter including a first system frame number of the macro node; and

transmit an assignment of the unique identifier and the femto cell and the timing parameter to the femto cell for determining a second system frame number of the femto cell based on the first system frame number of the macro node and an offset value in the unique identifier, wherein the first and second system frame numbers are configured to synchronize with each other based on a periodic increment of the first system frame number received by the femto cell via a downlink channel to avoid time drifts, the periodic increment of the first system frame number is configured to be broadcast through a transport channel, and the transport channel is configured to be mapped to the downlink channel.

14. An apparatus of a network entity that facilitates a hand-in of a user equipment to a femto cell, comprising:

means for identifying a macro node assigned to the femto cell;

means for assigning a unique identifier to the femto cell, wherein the unique identifier is taken from a Cartesian product of a set of primary scrambling codes and a set of offset values, and the set of offset values is related to a timing parameter including a first system frame number of the macro node; and

means for transmitting an assignment of the unique identifier and the femto cell, and the timing parameter to the femto cell for determining a second system frame number of the femto cell based on the first system frame number of the macro node and an offset value in the unique identifier, wherein the first and second system frame numbers are configured to synchronize with each other based on a periodic increment of the first system frame number received by the femto cell via a downlink channel to avoid time drifts, the periodic increment of the first system frame number is configured to be broadcast through a transport channel, and the transport channel is configured to be mapped to the downlink channel.

15. A method that facilitates performing a hand-in of a wireless terminal to a femto cell, comprising:

detecting, by the wireless terminal, a target femto cell during an active call, the wireless terminal being connected to a macro node;

ascertaining a global identifier associated with the target femto cell, wherein the global identifier is determined by a network entity and is taken from a Cartesian product of a set of primary scrambling codes and a set of offset values, and the set of offset values is related to a timing parameter including a first system frame number of the target femto cell; and

reporting the global identifier and the first system frame number of the target femto cell to an external entity, wherein the first system frame number is determined based on a second system frame number of the macro node and an offset value in the global identifier, wherein the first and second system frame numbers are configured to synchronize with each other based on a periodic increment of the first system frame number received by the femto cell via a downlink channel to avoid time drifts, the periodic increment of the first system frame number is configured to be broadcast through a transport channel, and the transport channel is configured to be mapped to the downlink channel.

16. The method of claim 15, further comprising receiving a request to ascertain the global identifier, wherein the global identifier is ascertained in response to the request.

17. The method of claim 15, wherein the ascertaining is performed automatically upon a detection of the target femto cell.

18. An apparatus of a wireless terminal that facilitates performing a hand-in of the wireless terminal to a femto cell, the apparatus comprising:

a processor configured to execute computer executable components stored in memory, the components including;

a detection component configured to detect a target femto cell during an active call, the wireless terminal being connected to a macro node;

an identifier component configured to ascertain a global identifier associated with the target femto cell, wherein the global identifier is determined by a network entity and is taken from a Cartesian product of a set of primary scrambling codes and a set of offset values, and the set of offset values is related to a timing parameter including a first system frame number of the target femto cell; and

a transmitting component configured to report the global identifier and the first system frame number of the target femto cell to an external entity, wherein the first system frame number is determined based on a second system frame number of the macro node and an offset value in the global identifier, wherein the first and second system frame numbers are configured to synchronize with each other based on a periodic increment of the first system frame number received by the femto cell via a downlink channel to avoid time drifts, the periodic increment of the first system frame number is configured to be broadcast through a transport channel, and the transport channel is configured to be mapped to the downlink channel.

19. The apparatus of claim 18, further comprising a receiving component configured to receive a request to provide the global identifier, wherein the identifier component is configured to determine the global identifier in response to the request.

20. The apparatus of claim 18, wherein the identifier component is configured to automatically determine the global identifier upon a detection of the target femto cell.

21. The apparatus of claim 18, wherein the global identifier is received without an interruption of a source cell active mode traffic.

22. A non-transitory computer-readable storage medium embedded thereon a computer executable program comprising code for causing a wireless terminal to perform a hand-in to a femto cell, the code causing at least one computer of the wireless terminal to:

detect a target femto cell during an active call, the wireless terminal being connected to a macro node;

ascertain a global identifier associated with the target femto cell, wherein the global identifier is determined by a network entity and is taken from a Cartesian product of a set of primary scrambling codes and a set of offset values, and the set of offset values is related to a timing parameter including a first system frame number of the target femto cell; and

report the global identifier and the first system frame number of the target femto cell to an external entity, wherein the first system frame number is determined based on a second system frame number of the macro node and an offset value in the global identifier, wherein the first and second system frame numbers are configured to synchronize with each other based on a periodic increment of the first system frame number received by the femto cell via a downlink channel to avoid time drifts, the periodic increment of the first system frame number is configured to be broadcast through a transport channel, and the transport channel is configured to be mapped to the downlink channel.

23. The non-transitory computer-readable storage medium of claim 22, wherein the code further causes the at least one computer to:

receive a request to provide the global identifier, and determine the global identifier in response to the request.

24. An apparatus of a wireless terminal that facilitates performing a hand-in of the wireless terminal to a femto cell, comprising:

means for detecting a target femto cell during an active call, the wireless terminal being connected to a macro node;

means for ascertaining a global identifier associated with the target femto cell, wherein the global identifier is determined by a network entity and is taken from a Cartesian product of a set of primary scrambling codes and a set of offset values, and the set of offset values is related to a timing parameter including a first system frame number of the target femto cell; and

means for reporting the global identifier and the first system frame number of the target femto cell to an external entity, wherein the first system frame number is determined based on a second system frame number of the macro node and an offset value in the global identifier, wherein the first and second system frame numbers are configured to synchronize with each other based on a periodic increment of the first system frame number received by the femto cell via a downlink channel to avoid time drifts, the periodic increment of the first system frame number is configured to be broadcast through a transport channel, and the transport channel is configured to be mapped to the downlink channel.

25. The apparatus of claim 24, wherein the means for ascertaining comprises means for automatically ascertaining the global identifier upon a detection of the target femto cell.