Wireless device, network node and methods therein, computer programs and computer-readable mediums comprising the computer programs, for cell monitoring for cell reselection

Patent metadata

Field	Value
Publication number	US-9565611-B2
Application number	US-201414409242-A
Country	US
Kind code	B2
Filing date	Nov 3, 2014
Priority date	Nov 4, 2013
Publication date	Feb 7, 2017
Grant date	Feb 7, 2017

Abstract

A wireless device obtains information associated with N layers, which may be used for cell reselection. The information comprises which M layers out of the N layers are to be used for monitoring according to detection and measurement requirements for absolute priority reselection. The wireless device monitors layers, of any priority, only out of the M layers, when one or more first signal measurements on a serving cell are below or equal to a first threshold, or when one or more second signal measurements on the serving cell are below or equal to a second threshold. The wireless device monitors layers with a priority higher than a priority of the serving layer out of the N layers when the one or more first signal measurements are above the first threshold, and when the one or more second signal measurements are above the signal threshold.

First claim

The invention claimed is:

1. A method performed by a wireless device of cell monitoring for cell reselection, the wireless device operating in a wireless communications network, the method comprising:
obtaining information associated with N layers, which information may be used by the wireless device for at least cell reselection, wherein the information comprises which M layers out of the N layers are to be used by the wireless device for monitoring according to detection and measurement requirements for absolute priority reselection, wherein each of the N layers, and a serving layer of the wireless device is assigned an absolute priority; and
monitoring layers, of any priority, only out of the M layers, when one or more first signal measurements on a serving cell of the wireless device are below or equal to a first signal threshold, or when one or more second signal measurements on the serving cell are below or equal to a second signal threshold, and
monitoring layers with a priority higher than a priority of the serving layer out of the N layers when the one or more first signal measurements on the serving cell are above the first signal threshold, and when the one or more second signal measurements on the serving cell are above the second signal threshold.

2. The method of claim 1 , wherein the information associated with the N layers comprising which M layers out of the N layers are to be used by the wireless device for monitoring according to detection and measurement requirements for absolute priority reselection, comprises an indication that N-M layers are to be used for monitoring only when the one or more first signal measurements on the serving cell are above the first signal threshold, and when the one or more second signal measurements on the serving cell are above the second signal threshold.

3. The method of claim 1 , wherein each layer is related to a respective carrier frequency.

4. The method of claim 1 , wherein the obtaining the information associated with the N layers, comprises receiving the information from a network node operating in the wireless communications network.

5. The method of claim 1 , wherein the obtaining the information associated with the N layers, is performed autonomously by the wireless device, based on internal information in the wireless device.

6. The method of claim 1 , wherein the obtaining the information associated with the N layers, is performed based on pre-defined rules or pre-defined values.

7. The method of claim 1 , further comprising:
performing cell reselection, on the monitored layers,
according to the detection and measurement requirements for absolute priority reselection when the one or more first signal measurements on the serving cell of the wireless device are below or equal to the first signal threshold, or when the one or more second signal measurements on the serving cell are below or equal to the second signal threshold, and
according to a higher priority search, when the one or more first signal measurements on the serving cell are above the first signal threshold, and when the one or more second signal measurements on the serving cell are above the second signal threshold.

8. The method of claim 1 , further comprising adjusting the obtained information based on at least one of: a speed of the wireless device and a state of a battery of the wireless device.

9. The method of claim 8 , further comprising receiving a configuration from a network node operating in the wireless communications network to adjust the obtained information based on the at least one of: the speed of the wireless device and the state of the battery of the wireless device.

10. The method of claim 1 , wherein the first signal threshold is a signal strength threshold and the second signal threshold is a signal quality threshold.

11. The method of claim 1 , wherein at least one of: the one or more first signal measurements and the one or more second signal measurements is one of: one or more signal strength measurements and one or more signal quality measurements.

12. The method of claim 1 , wherein the monitoring comprises one or more of: detecting a cell, measuring a cell and evaluating a cell for cell reselection.

13. A non-transitory computer readable medium storing software instructions executable by at least one processor of a wireless device, whereby the wireless device is operative to:
obtain information associated with N layers, which information may be used by the wireless device for at least cell reselection, wherein the information comprises which M layers out of the N layers are to be used by the wireless device for monitoring according to detection and measurement requirements for absolute priority reselection, wherein each of the N layers, and a serving layer of the wireless device is assigned an absolute priority; and
monitoring layers, of any priority, only out of the M layers, when one or more first signal measurements on a serving cell of the wireless device are below or equal to a first signal threshold, or when one or more second signal measurements on the serving cell are below or equal to a second signal threshold, and
monitoring layers with a priority higher than a priority of the serving layer out of the N layers when the one or more first signal measurements on the serving cell are above the first signal threshold, and when the one or more second signal measurements on the serving cell are above the second signal threshold.

14. A method performed by a network node for determining information for a wireless device to perform cell reselection, the network node and the wireless device operating in a wireless communications network, the method comprising:
determining information associated with N layers, which information may be used by the wireless device for at least cell reselection, wherein the information comprises:
which M layers out of the N layers are to be used by the wireless device for monitoring according to detection and measurement requirements for absolute priority reselection, wherein each of the N layers, and a serving layer of the wireless device is assigned an absolute priority, and wherein the absolute priority reselection, wherein layers, of any priority, only out of the M layers are monitored by the wireless device, is performed when one or more first signal measurements by the wireless device on a serving cell of the wireless device are below or equal to a first signal threshold, or when one or more second signal measurements by the wireless device on the serving cell are below or equal to a second signal threshold; and
which high priority layers out of the N layers are to be used by the wireless device for monitoring only during a higher priority search, which is performed when the one or more first signal measurements on the serving cell are above the first signal threshold, and when the one or more second signal measurements on the serving cell are above the second signal threshold, and

sending the information associated with the N layers, to the wireless device.

15. The method of claim 14 , wherein the information associated with the N layers comprising which M layers out of the N layers are to be used by the wireless device for monitoring according to detection and measurement requirements for absolute priority reselection, comprises an indication that N−M layers are to be used for monitoring only when the one or more first signal measurements on the serving cell are above the first signal threshold, and when the one or more second signal measurements on the serving cell are above the second signal threshold.

16.

Assignees

• Ericsson Telefon Ab L M

Inventors

• Callender Christopher
• Kazmi Muhammad

Classifications

• H04B17/318

  Received signal strength · CPC title

• H04W48/16 Primary

  Discovering, processing access restriction or access information · CPC title

• H04W36/32

  by location or mobility data, e.g. speed data · CPC title

• H04W36/30 Primary

  by measured or perceived connection quality data · CPC title

• H04W36/04

  Reselecting a cell layer in multi-layered cells · CPC title