Multiple input multiple output (MIMO) based concurrent scan of neighbor cells

• US 8,730,915 B2
• Filed: 09/20/2011
• Issued: 05/20/2014
• Est. Priority Date: 09/20/2011
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Cheng, Steven D., Gurski, Remi J., Lee, Kuo-Chun, Chin, Tom, Shi, Guangming
• Primary Examiner(s): Chriss, Andrew
• Assistant Examiner(s): Rivas, Salvador E
• Application Number:
  US13/237,675
• Publication Number:
  US 20130072189A1
• Time in Patent Office: 973 Days
• Field of Search: None
• US Class Current: 370/331
• CPC Class Codes: H04B 1/1027 assessing signal quality or detecting noise/interference for the received signal
• CPC Class Codes: H04B 1/713 using frequency hopping
• CPC Class Codes: H04B 17/318 Received signal strength
• CPC Class Codes: H04B 17/382 for resource allocation, admission control or handover
• CPC Class Codes: H04B 3/38 for signals in two different frequency ranges transmitted in opposite directions over the same transmission path
• CPC Class Codes: H04B 7/0413 MIMO systems
• CPC Class Codes: H04B 7/0452 Multi-user MIMO systems
• CPC Class Codes: H04B 7/12 Frequency diversity
• CPC Class Codes: H04J 11/003 at the transmitter transmission to multiple receive units in multiple input multiple output [MIMO] H04B7/0452; transmit antenna weighting H04B7/0615
• CPC Class Codes: H04L 5/0023 Time-frequency-space
• CPC Class Codes: H04N 21/42676 for modulating an analogue carrier signal to encode digital information or demodulating it to decode digital information, e.g. ADSL or cable modem
• CPC Class Codes: H04W 36/00837 Determination of triggering parameters for hand-off
• CPC Class Codes: H04W 36/0094 Definition of hand-off measurement parameters
• CPC Class Codes: H04W 36/14 Reselecting a network or an air interface
• CPC Class Codes: H04W 36/302 due to low signal strength
• CPC Class Codes: H04W 40/02 Communication route or path selection, e.g. power-based or shortest path routing
• CPC Class Codes: H04W 40/36 due to handover
• CPC Class Codes: H04W 88/06 adapted for operation in multiple networks or having at least two operational modes, e.g. multi-mode terminals

Abstract

Methods, systems, and devices are described for concurrently performing handoff-related measurements for neighbor cells using multiple input multiple output (MIMO) antenna resources. In one example, a mobile device is in communication with a serving cell. Handoff-related measurements of first wireless signals from a first neighbor cell are performed. The first wireless signals are received at first MIMO antenna resources of a device. Handoff-related measurements of second wireless signals from a second neighbor cell are performed, as well. The second wireless signals are received at second MIMO antenna resources concurrently with the first wireless signals received at the first MIMO antenna resources. The first handoff-related measurements and the second handoff-related measurements may be performed during a scan interval. A type of handoff-related measurement to perform may be determined based on a determined length of the scan interval.

Claims

1. A method comprising:

determining whether a mobile device is in an idle mode; and

in response to determining that the mobile device is in the idle mode;

determining a length of a scan interval;

determining, by the mobile device, a type of handoff-related measurement to perform for a different frequency band than a frequency band of a serving cell based on the determined length of the scan interval;

performing first handoff-related measurements of first wireless signals from a first neighbor cell received at a first multiple input multiple output (MIMO) antenna resource of the mobile device, wherein the device is in communication with the serving cell, and wherein the first neighbor cell is in a same frequency band as the serving cell;

tuning a receiver associated with a second MIMO antenna resource from the frequency band of the serving cell to the different frequency band, wherein the different frequency band is a frequency band of a second neighbor cell;

performing second handoff-related measurements of second wireless signals from the second neighbor cell received at the second MIMO antenna resource of the mobile device, wherein the second handoff-related measurements are of the determined type of handoff-related measurement, the second wireless signals received at the second MIMO antenna resource concurrently with the first wireless signals being received at the first MIMO antenna resource;

determining, by the mobile device, to decode the second wireless signals based at least in part on the determined length of the scan interval;

decoding a second downlink message received at the second MIMO antenna resource from the second neighbor cell based on a determination to decode; and

tuning the receiver associated with the second MIMO antenna resource from the different frequency band to the frequency band of the serving cell.

2. The method of claim 1, further comprising:

performing the first handoff-related measurements and the second handoff-related measurements during the scan interval.

3. The method of claim 1, wherein,

the first handoff-related measurements and the second handoff-related measurements comprise a power measurement.

4. The method of claim 1, wherein,

the first handoff-related measurements and the second handoff related measurements comprise a signal quality measurement.

5. The method of claim 4, wherein,

the signal quality measurement comprises a signal-to-noise ratio (SNR), a carrier to interference-plus-noise-ratio (CINR), a bit error ratio (BER), an energy per bit to noise power spectral density ratio (Eb/NO), or an energy per symbol per noise power spectral density ratio (ES/NO).

6. The method of claim 1, wherein,

the first handoff-related measurements comprise a power measurement and the second handoff-related measurements comprise a signal quality measurement.

7. The method of claim 1, further comprising:

decoding a first downlink message received at the first MIMO antenna resource from the first neighbor cell.

8. The method of claim 1, wherein,

the first neighbor cell comprises a first radio access technology (RAT);

and

the second neighbor cell comprises the first RAT.

9. The method of claim 8, wherein,

the serving cell comprises the first RAT.

10. The method of claim 1, wherein,

the first neighbor cell comprises a first radio access technology (RAT);

and

the second neighbor cell comprises a second RAT different from the first RAT.

11. A device comprising:

a plurality of multiple input multiple output (MIMO) antenna resources;

a transceiver coupled with the plurality of MIMO antenna resources;

a processor;

memory in electronic communication with the processor; and

instructions stored in the memory, the instructions being executable by the processor to;

determine whether the device is in an idle mode; and

in response to a determination that the device is in the idle mode;

determine a length of a scan interval;

determine a type of handoff-related measurement to perform for a different frequency band than a frequency band of a serving cell based on the determined length of the scan interval;

perform first handoff-related measurements of first wireless signals from a first neighbor cell received at a first MIMO antenna resource of the plurality of MIMO antenna resources, wherein the device is in communication with the serving cell, and wherein the first neighbor cell is in a same frequency band as the serving cell;

tune a receiver associated with a second MIMO antenna resource from the frequency band of the serving cell to the different frequency band, wherein the different frequency band is a frequency band of a second neighbor cell;

perform second handoff-related measurements of second wireless signals from the second neighbor cell received at the second MIMO antenna resource of the plurality of MIMO antenna resources, wherein the second handoff-related measurements are of the determined type of handoff-related measurement, the second wireless signals received at the second MIMO antenna resource concurrently with the first wireless signals being received at the first MIMO antenna resource;

determine to decode the second wireless signals based at least in part on the determined length of the scan interval;

decode a second downlink message received at the second MIMO antenna resource from the second neighbor cell based on a determination to decode; and

tune the receiver associated with the second MIMO antenna resource from the different frequency band to the frequency band of the serving cell.

12. The device of claim 11, wherein the instructions are executable by the processor to:

perform the first handoff-related measurements and the second handoff-related measurements during the scan interval.

13. The device of claim 11, wherein,

the first handoff-related measurements and the second handoff-related measurements comprise a power measurement.

14. The device of claim 11, wherein,

the first handoff-related measurements and the second handoff related measurements comprise a signal quality measurement.

15. The device of claim 11, wherein,

the first handoff-related measurements comprise a power measurement and the second handoff-related measurements comprise a signal quality measurement.

16. The device of claim 11, wherein, the instructions are executable by the processor to:

decode a first downlink message received at the first MIMO antenna resource from the first neighbor cell.

17. A computer program product comprising a non-transitory computer-readable medium, the non-transitory computer-readable medium comprising:

code for determining whether a device is in an idle mode; and

code for performing the following in response to determining that the device is in the idle mode;

determining a length of a scan interval;

determining a type of handoff-related measurement to perform for a different frequency band than a frequency band of a serving cell based on the determined length of the scan interval;

performing first handoff-related measurements of first wireless signals from a first neighbor cell received at a first multiple input multiple output (MIMO) antenna resource of the device, the device in communication with the serving cell, wherein the first neighbor cell is in a same frequency band as the serving cell;

tuning a receiver associated with a second MIMO antenna resource from the frequency band of the serving cell to the different frequency band, wherein the different frequency band is a frequency band of a second neighbor cell;

performing second handoff-related measurements of second wireless signals from the second neighbor cell received at the second MIMO antenna resource of the device, wherein the second handoff-related measurements are of the determined type of handoff-related measurement, the second wireless signals received at the second MIMO antenna resource concurrently with the first wireless signals being received at the first MIMO antenna resource;

determining to decode wireless signals based at least in part on the determined length of the scan interval;

decoding a second downlink message received at the second MIMO antenna resource from the second neighbor cell based on a determination to decode; and

tuning the receiver associated with the second MIMO antenna resource from the different frequency band to the frequency band of the serving cell.