Avoiding serving cell interruption

• US 9,742,533 B2
• Filed: 12/05/2013
• Issued: 08/22/2017
• Est. Priority Date: 01/18/2013
• Status: Active Grant

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Kazmi, Muhammad, Chapman, Thomas
• Primary Examiner(s): Wilson, Robert
• Application Number:
  US14/760,230
• Publication Number:
  US 20150341148A1
• Time in Patent Office: 1,356 Days
• CPC Class Codes: H04L 5/001 the frequencies being arranged in component carriers
• CPC Class Codes: H04L 5/0032 Distributed allocation, i.e. involving a plurality of allocating devices, each making partial allocation
• CPC Class Codes: H04L 5/0037 Inter-user or inter-terminal allocation
• CPC Class Codes: H04L 5/0039 Frequency-contiguous, i.e. with no allocation of frequencies for one user or terminal between the frequencies allocated to another
• CPC Class Codes: H04L 5/0041 Frequency-non-contiguous
• CPC Class Codes: H04L 5/0073 Allocation arrangements that take into account other cell interferences for intercell interference mitigation or co-ordination in orthogonal multiplex systems H04J11/005
• CPC Class Codes: H04L 5/0078 Timing of allocation
• CPC Class Codes: H04L 5/0091 Signaling for the administration of the divided path
• CPC Class Codes: H04L 5/0098 Signalling of the activation or deactivation of component carriers, subcarriers or frequency bands
• CPC Class Codes: H04W 24/08 Testing, supervising or monitoring using real traffic
• CPC Class Codes: H04W 72/1273 of downlink data flows

Abstract

Techniques for minimizing the loss of radio signals transmitted on and/or received from serving cells in a multi-carrier system by selectively adapting the time instance at which a wireless terminal: (1) changes its radio frequency (RF) bandwidth or activates a second RF chain or any additional RF chain for measuring on one or more secondary serving cells, and/or (2) performs setup or release of one or more secondary serving cells. An example method, implemented in a radio network node, comprises determining (510) a scheduling instance during which a wireless terminal is expected to be scheduled on at least one cell; and, determining (520) a timing at which to send a setup or release command for at least one secondary cell such that the requested set up or release procedure does not coincide with the scheduling instance.

Claims

1. A method in a radio network node adapted to serve a multi-carrier capable wireless terminal, characterized in that the method comprises:

determining a scheduling instance during which the wireless terminal is expected to be scheduled, but not currently scheduled, on at least one cell;

determining a timing at which to send a setup command or a release command for a secondary cell, based on the scheduling instance, such that a corresponding setup procedure or release procedure does not coincide with the scheduling instance; and

sending the setup command or release command at the determined timing.

2. The method of claim 1, wherein determining the timing is further based on one or more of:

knowledge at the radio network node of instances at which the wireless terminal performs measurements;

a type of service provided to the wireless terminal;

measurement reporting instances at the wireless terminal;

scheduling of data to the wireless terminal by the radio network node;

a scheduling request corresponding to the wireless terminal.

3. The method of claim 1, wherein the timing for sending the setup command or release command is delayed, based on whether an amount of buffered data for the wireless terminal exceeds a threshold amount.

4. The method of claim 1, wherein the timing for sending the setup command or release command is determined with respect to a reference time instance.

5. The method of claim 1, further comprising receiving a capability of the wireless terminal from the wireless terminal, which capability indicates that the wireless terminal is capable of adapting the time instances for performing one or more radio measurements on a deactivated secondary cell and/or adapting the time instance for applying a setup command or release command for a secondary cell, such that the timing does not coincide with the scheduling instance during which the wireless terminal is expected to be scheduled on at least one cell by a radio network node.

6. The method of claim 1, wherein the setup command or release command is any of:

configuration of the secondary cell, de-configuration of the secondary cell, activation of the secondary cell and deactivation of the secondary cell.

7. The method of claim 1, wherein the at least one cell on which the wireless terminal is expected to be scheduled is any cell other than the secondary cell for which the setup command or the release command is to be sent.

8. A method, in a multi-carrier-capable wireless terminal, characterized in that the method comprises:

determining a scheduling instance during which the wireless terminal is expected to be scheduled, but not currently scheduled, on at least one cell by a radio network node; and

determining a timing at which to change the radio-frequency, RF, bandwidth of a receiver, or to activate additional RF receiver circuitry, for performing one or more radio measurements on a deactivated secondary cell or for applying a setup command or release command for a secondary cell, such that the timing does not coincide with the scheduling instance; and

performing one or more radio measurements on the deactivated secondary cell or applying the setup command or release command at the determined timing.

9. The method of claim 8, wherein determining the timing is performed autonomously by the wireless terminal, based on one or more pre-determined rules.

10. The method of claim 8, wherein the pre-determined rules comprise one or more of:

the wireless terminal is allowed to apply the received setup command or release command with a particular delay;

the wireless terminal is allowed to apply the received setup command or release command during a time when it is not scheduled by the radio network node or a particular time after has been scheduled.

11. The method of claim 8, wherein determining the timing is based on a timing indication received from the radio network node.

12. The method of claim 8, wherein the method further comprises one or more of:

adapting the time instances at which the wireless terminal performs measurements, based on the respective determined timing; and

adapting the time instance at which the wireless terminal applies the setup command or release command based on the respective determined timing.

13. The method of claim 12, wherein the method further comprises adapting one or more measurement operations to meet one or more pre-defined requirements for the one or more radio measurements.

14. The method of claim 13, wherein adapting one or more measurement operations comprises one or more of:

adapting a radio measurement sampling rate;

adapting a length of radio measurement samples; and

adapting an instance of obtaining measurement samples.

15. The method of claim 13, wherein the one or more pre-defined requirements comprise one or more of:

cell identification delay;

CGI reporting delay;

measurement period;

measurement reporting delay;

measurement reporting time;

wireless terminal transmit timing accuracy;

measurement accuracy;

evaluation period of out-of-sync in RLM; and

evaluation period of in sync in RLM.

16. The method of claim 8, further comprising signaling a capability for the wireless terminal to the radio network node, which capability indicates that the wireless terminal is capable of adapting the time instances for performing one or more radio measurements on a deactivated secondary cell and/or adapting the time instance for applying a setup command or release command for a secondary cell, such that the timing does not coincide with the scheduling instance during which the wireless terminal is expected to be scheduled on at least one cell by a radio network node.

17. The method of claim 8, wherein the setup command or release command is any of:

configuration of the secondary cell, de-configuration of the secondary cell, activation of the secondary cell and deactivation of the secondary cell.

18. The method of claim 8, wherein the at least one cell on which the wireless terminal is expected to be scheduled is any cell other than the secondary cell for which the setup command or the release command is to be applied.

19. A radio network node adapted to serve a multi-carrier capable wireless terminal, the radio network node comprising a communication interface circuit and a processing circuit, characterized in that the processing circuit is configured to:

determine a scheduling instance during which the wireless terminal is expected to be scheduled, but not currently scheduled, on at least one cell;

determine a timing at which to send a setup command or a release command for a secondary cell, based on the scheduling instance, such that a corresponding setup procedure or release procedure does not coincide with the scheduling instance; and

wherein the communication interface circuit is configured to send the setup command or release command at the determined timing.

20. The radio network node of claim 19, wherein the processing circuit is configured to determine the timing based further on one or more of:

knowledge at the radio network node of instances at which the wireless terminal performs measurements;

a type of service provided to the wireless terminal;

measurement reporting instances corresponding to the wireless terminal;

scheduling of data to the wireless terminal by the radio network node; and

a scheduling request corresponding to the wireless terminal.

21. The radio network node of claim 19, wherein the processing circuit is configured to delay the timing for sending the setup command or release command, based on whether an amount of buffered data for the wireless terminal exceeds a threshold amount.

22. The radio network node of claim 19, wherein the processing circuit is further configured to receive, via the communication interface circuit, a capability of the wireless terminal from the wireless terminal, which capability indicates that the wireless terminal is capable of adapting the time instances for performing one or more radio measurements on a deactivated secondary cell and/or adapting the time instance for applying a setup command or release command, such that the timing does not coincide with the scheduling instance during which the wireless terminal is expected to be scheduled on at least one cell by a radio network node.

23. A wireless terminal adapted for multi-carrier operation and comprising a communication interface circuit and a processing circuit, characterized in that the processing circuit is configured to:

determine a scheduling instance during which the wireless terminal is expected to be scheduled, but not currently scheduled, on at least one cell by a radio network node;

determine a timing at which to change the radio-frequency, RF, bandwidth of a receiver, or to activate additional RF receiver circuitry, for performing one or more radio measurements on a deactivated secondary cell or for applying a setup command or release command on a secondary cell, such that the timing does not coincide with the scheduling instance; and

wherein the communication interface circuit is configured to perform one or more radio measurements on the deactivated secondary cell or apply the setup command or release command at the determined timing.

24. The wireless terminal of claim 23, wherein the processing circuit is configured to determine the timing autonomously, based on one or more pre-determined rules.

25. The wireless terminal of claim 23, wherein the processing circuit is configured to determine the timing based on a timing indication received from the radio network node.