Wireless communication device capable of scanning for available base stations using reduced bandwidth

• US 9,356,757 B2
• Filed: 09/28/2012
• Issued: 05/31/2016
• Est. Priority Date: 12/30/2011
• Status: Active Grant

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Broadcom Corporation (Broadcom, Inc.)
• Inventors: Stauffer, Erik, Lorenz, Robert Gustav, Rath, Kamlesh
• Primary Examiner(s): Elliott, IV, Benjamin H
• Assistant Examiner(s): Nowlin, Eric
• Application Number:
  US13/631,362
• Publication Number:
  US 20130170418A1
• Time in Patent Office: 1,341 Days
• Field of Search: 370/252, 370/329, 370/241, 370/254, 370/347, 370/311, 370/330, 370/332, 370/345, 455/434, 455/67.11, 455/226.1, 455/41.2, 455/423, 455/150.1, 455/161.1, 455/450, 455/452.2, 455/500, 455/73, 375/219
• US Class Current: 1/1
• CPC Class Codes: H04L 27/38 Demodulator circuits; Receiver circuits
• CPC Class Codes: H04L 5/0053 Allocation of signaling, i.e. of overhead other than pilot signals
• CPC Class Codes: H04W 48/16 Discovering, processing access restriction or access information
• CPC Class Codes: H04W 52/0229 where the received signal is a wanted signal
• CPC Class Codes: H04W 52/0232 according to average transmission signal activity
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A wireless communication device is disclosed that includes multiple antennas capable of being used for carrier aggregation, and that uses its additional antennas to scan for available base stations without interfering with connectivity to a current base station and/or while maximizing useable bandwidth. The wireless communication device may scan using multiple of the antennas to maximize scanning results and reduce scan time, and may scan for available base stations using some of its antennas while maintaining its connection to the current base station with its other antennas. The device can also analyze control channel portions of received signals to utilize periods of signal inactivity to scan for available base stations, such as DRX or SPS modes of operation. In addition, the device can measure various parameters to optimize its scanning capabilities.

Claims

1. A wireless communication device, comprising:

a plurality of transceiver modules configured to communicate with a current base station wherein at least one of the transceiver modules receives a signal from the current base station that includes a data sub-frame having a control channel portion and a payload portion, and wherein the control channel portion indicates to the wireless communication device that the payload portion includes at least one unallocated data symbol that has not been allocated to the wireless communication device; and

a scanning module configured to;

select one of the plurality of transceiver modules as a scanning transceiver module;

control the scanning transceiver module to scan for an available base station on different respective frequencies; and

control the scanning transceiver module to scan for the available base station during times corresponding to the at least one unallocated data symbol of the payload portion based on the indication of the control channel portion.

2. The wireless communication device of claim 1,

wherein during a measurement gap, the scanning module controls the scanning transceiver module and a second scanning transceiver module to scan for the available base station using the different respective frequencies.

14. The wireless communication device of claim 2, further comprising:

a multiplexer,

wherein the scanning module controls the scanning transceiver module to scan for the available base station one at a time in a round robin configuration, and

wherein the multiplexer combines data received by the scanning transceiver module.

15. The wireless communication device of claim 2, wherein the scanning module is configured to identify frequencies to be scanned, and

wherein the scanning module selects more than one scanning transceiver module that corresponds to the identified frequencies for performing the scan for the available base station.

3. A wireless communication device, comprising:

a plurality of transceiver modules configured to communicate with a current base station;

a measurement module configured to measure a signal characteristic of signals received from the current base station by each of the plurality of transceiver modules;

a controller module configured to;

compare the measured signal characteristic of each of the plurality of transceiver modules to a predetermined threshold, and

identify a scanning transceiver module from among the plurality of transceiver modules whose measured signal characteristic value is below the predetermined threshold and a communication transceiver module from among the plurality of transceiver modules whose measured signal characteristic value exceeds the predetermined threshold; and

a scanning module configured to control the scanning transceiver module to scan for an available base station and to control the communication transceiver module to simultaneously communicate with the current base station.

4. The wireless communication device of claim 3, wherein the scanning module controls multiple transceiver modules that are not scanning to communicate with the current base station.

5. The wireless communication device of claim 3, wherein at least one of the transceiver modules receives a signal from the current base station,

wherein the signal includes a data sub-frame having a plurality of resource elements that each have a frequency and time allocation, and

wherein the data sub-frame includes a control channel portion and a payload portion.

6. The wireless communication device of claim 5, wherein the scanning module controls fewer than all of the plurality of transceiver modules to decode the control channel portion of the data sub-frame, and controls at least one of a remainder of the transceiver modules to scan for the available base station.

7. The wireless communication device of claim 5,

wherein, when the measured signal characteristic of the signal exceeds the predetermined threshold, the scanning module controls fewer than all of the plurality of transceiver modules to decode the payload portion of the signal, and controls at least one of a remainder of the transceiver modules to scan for the available base station.

8. The wireless communication device of claim 5, wherein the scanning module controls a transceiver module of the plurality of transceiver modules to disregard a resource element of the signal, and to instead scan for the available base station during the time allocation associated with the resource element.

10. The wireless communication device of claim 5, wherein the control channel portion indicates to the wireless communication device that less than all data symbols of the payload portion have been allocated to the wireless communication device, and

wherein the scanning module controls the scanning transceiver module to scan for the available base station during the time corresponding to the unallocated data symbols.

11. The wireless communication device of claim 5, wherein the wireless communication device operates in Discontinuous Reception (DRX) mode, and

wherein the scanning module controls the scanning transceiver module to scan for the available base station during DRX periods of inactivity.

12. The wireless communication device of claim 5, wherein the control channel portion indicates to the wireless communication device that a portion of the payload portion has been allocated to the wireless communication device for a current sub-frame and for periodic future sub-frames as part of semi-persistent scheduling, and

wherein the scanning module controls at least one of the scanning transceiver module to scan for the available base station during the control channel portion of the periodic future sub-frames.

13. The wireless communication device of claim 3, wherein the scanning module causes transceiver modules with stronger signal characteristics to scan for the available base station more frequently than transceiver modules having weaker signal characteristics.

16. The wireless communications device of claim 3, wherein the measured signal characteristic is signal strength.

17. The wireless communication device of claim 3, wherein the comparing includes ranking the plurality of transceiver modules according to their respective measured signal characteristics, and

wherein the controller module is configured to identify as the scanning transceiver module the one of the plurality of transceiver modules that has the lowest ranking.

9. A wireless communication device, comprising:

a plurality of transceiver modules configured to communicate with a current base station, wherein at least one of the transceiver modules receives a signal from the current base station that includes a data sub-frame having a control channel portion and a payload portion, and wherein the control channel portion indicates to the wireless communication device that it is not necessary to monitor control channel portions of future data sub-frames, and

a scanning module configured to select a transceiver module as a scanning transceiver module and to control the scanning transceiver module to scan for an available base station, wherein the scanning module controls the scanning transceiver module to scan for the available base station during the time that otherwise would have been allocated to decoding control channel portions of the future data sub-frames while maintaining connection with the current base station,

wherein each of the future data sub-frames include a corresponding data allocation to be used by the wireless communication device.