Method and apparatus for migrating from licensed spectrum to unlicensed spectrum

• US 10,064,113 B2
• Filed: 12/30/2016
• Issued: 08/28/2018
• Est. Priority Date: 12/30/2016
• Status: Active Grant

• Current Assignee: T-Mobile USA, Inc. (Deutsche Telekom AG)
• Original Assignee: T-Mobile USA, Inc. (Deutsche Telekom AG)
• Inventors: Karimli, Yasmin, Nimbavikar, Gunjan
• Primary Examiner(s): Yao, Kwang B
• Assistant Examiner(s): Jeong, Moo Ryong
• Application Number:
  US15/396,089
• Publication Number:
  US 20180192340A1
• Time in Patent Office: 606 Days
• CPC Class Codes: H04B 17/336 Signal-to-interference ratio [SIR] or carrier-to-interference ratio [CIR]
• CPC Class Codes: H04W 16/14 Spectrum sharing arrangements between different networks
• CPC Class Codes: H04W 36/1446 wherein at least one of the networks is unlicensed
• CPC Class Codes: H04W 36/26 by agreed or negotiated communication parameters
• CPC Class Codes: H04W 36/302 due to low signal strength
• CPC Class Codes: H04W 48/16 Discovering, processing access restriction or access information
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]

Abstract

The systems, devices, and methods discussed herein are directed to migrating user equipment (UE) communication from an initially assigned channel in a licensed spectrum to an unlicensed spectrum available in a neighboring cell. As the UE is powered on, data connectivity between the UE and a carrier cell is checked, and if connected, an available neighbor cell in an unlicensed spectrum may be searched. If an available neighbor cell in the unlicensed spectrum is found, the carrier cell may hand off UE communication to the available neighbor cell in the unlicensed spectrum based on a type of the available neighbor cell and available quality for communication in the unlicensed spectrum.

Claims

1. A method for migrating a user equipment operating in a licensed spectrum to an unlicensed spectrum, the method comprising:

determining that a neighbor cell in the unlicensed spectrum is available;

determining a type of the available neighbor cell in the unlicensed spectrum;

determining that a signal quality of the available neighbor cell is below a type-specific predetermined threshold based on the type of the available neighbor cell;

determining that a carrier-licensed spectrum quality of the licensed spectrum is below a preselected value;

upon determining that the carrier-licensed spectrum quality of the licensed spectrum is below the preselected value, decrementing the type-specific predetermined threshold by a predetermined value and comparing the signal quality of the available neighbor cell to the decremented type-specific predetermined threshold until the signal quality of the available neighbor cell is equal to or above the decremented type-specific predetermined threshold; and

upon determining that the signal quality of the available neighbor cell in the unlicensed spectrum is equal to or above the decremented type-specific predetermined threshold, migrating to the available neighbor cell in the unlicensed spectrum.

2. A method of claim 1, wherein determining that the neighbor cell in the unlicensed spectrum is available comprises:

scanning for available neighbor cells in the unlicensed spectrum;

if a neighbor cell in the unlicensed spectrum is detected in response to the scanning, determining that the detected neighbor cell is the available neighbor cell; and

if no available neighbor cell in the unlicensed spectrum is detected in response to the scanning, waiting for a predetermined time period and repeating from the scanning for a predetermined number of times.

3. A method of claim 2, further comprising:

if no available neighbor cell in the unlicensed spectrum is detected in response to the scanning, and upon determining that the carrier-licensed spectrum quality is below the preselected value, moving to another channel within the carrier-licensed spectrum.

4. A method of claim 1, wherein determining the type of the available neighbor cell in the unlicensed spectrum comprises:

determining an associated network operator of the available neighbor cell; and

determining whether the available neighbor cell is a wireless local area network (WLAN) cell.

5. A method of claim 1, wherein the migrating is performed conditionally based on the neighbor cell not being utilized by another user equipment belonging to a same carrier as the user equipment.

6. A method of claim 1, wherein the signal quality of the available neighbor cell comprises a signal-to-noise ratio (SNR) of a detected signal in the unlicensed spectrum from the neighbor cell.

7. A system comprising:

one or more processors; and

a computer storage medium coupled to the one or more processors, the computer storage medium storing computer-readable instructions by the one or more processors, that when executed, cause the one or more processors to perform operations comprising;

determining that a neighbor cell in an unlicensed spectrum is available;

determining a type of the available neighbor cell in the unlicensed spectrum;

determining that a signal quality of the available neighbor cell is below a type-specific predetermined threshold based on the type of the available neighbor cell;

determining that a carrier-licensed spectrum quality is below a preselected value;

upon determining that the carrier-licensed spectrum quality is below the preselected value, decrementing the type-specific predetermined threshold by a predetermined value and comparing the signal quality of the available neighbor cell to the decremented type-specific predetermined threshold until the signal quality of the available neighbor cell is equal to or above the decremented type-specific predetermined threshold; and

upon determining that the available neighbor cell in the unlicensed spectrum is equal to or above the decremented type-specific predetermined threshold, migrating to the available neighbor cell in the unlicensed spectrum.

8. A system of claim 7, wherein determining that the neighbor cell in the unlicensed spectrum is available comprises:

scanning for available neighbor cells in the unlicensed spectrum;

if a neighbor cell in the unlicensed spectrum is detected in response to the scanning, determining that the detected neighbor cell is the available neighbor cell; and

if no available neighbor cell in the unlicensed spectrum is detected in response to the scanning, waiting for a predetermined time period and repeating from the scanning step for a predetermined times.

9. A system of claim 8, wherein the operations further comprise:

if no available neighbor cell in the unlicensed spectrum is detected in response to the scanning, and upon determining that the carrier-licensed spectrum quality is below the preselected value, moving to another channel within a carrier-licensed spectrum.

10. A system of claim 7, wherein determining the type of the available neighbor cell in the unlicensed spectrum comprises:

determining an associated network operator of the available neighbor cell; and

determining whether the available neighbor cell is a wireless local area network (WLAN) cell.

11. A system of claim 7, wherein the migrating is performed conditionally based on the neighbor cell not being utilized by another user equipment belonging to a same carrier as the user equipment.

12. A system of claim 7, wherein the signal quality of the available neighbor cell comprises a signal-to-noise ratio (SNR) of a detected signal in the unlicensed spectrum from the neighbor cell.

13. A non-transitory computer storage medium configured to store computer-readable instructions by a computer, that when executed, cause the computer to perform operations comprising:

determining that a neighbor cell in an unlicensed spectrum is available including scanning for available neighbor cells in the unlicensed spectrum, and

if a neighbor cell in the unlicensed spectrum is detected in response to the scanning, determining that the detected neighbor cell is the available neighbor cell, and

if no available neighbor cell in the unlicensed spectrum is detected in response to the scanning, waiting for a predetermined time period and repeating from the scanning step for a predetermined number of times;

determining a type of the available neighbor cell in the unlicensed spectrum;

determining that a signal quality of the available neighbor cell is below a type-specific predetermined threshold based on the type of the available neighbor cell;

determining that a carrier-licensed spectrum quality is below a preselected value;

upon determining that the carrier-licensed spectrum quality is below a preselected value, decrementing the type-specific predetermined threshold by a predetermined value and comparing the signal quality of the available neighbor cell to the decremented type-specific predetermined threshold until the signal quality of the available neighbor cell is equal to or above the decremented type-specific predetermined threshold; and

upon determining that the available neighbor cell in the unlicensed spectrum is equal to or above the decremented type-specific predetermined threshold, migrating to the available neighbor cell in the unlicensed spectrum.

14. A non-transitory computer storage medium of claim 13, wherein the operations further comprise:

if no available neighbor cell in the unlicensed spectrum is detected in response to the scanning, and upon determining that the carrier-licensed spectrum quality is below the preselected value, moving to another channel within a carrier-licensed spectrum.

15. A non-transitory computer storage medium of claim 13, wherein the

migrating is performed conditionally based on the neighbor cell not being utilized by another user equipment belonging to a same carrier as the user equipment.