Radio White Space Sensing

• US 20110223877A1
• Filed: 03/09/2010
• Published: 09/15/2011
• Est. Priority Date: 03/09/2010
• Status: Active Grant

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Sundström, Lars, Tillman, Fredrik, Rosenqvist, Anders
• Granted Patent: US 8,311,483 B2
• Time in Patent Office: Days
• US Class Current: 455/226.2
• CPC Class Codes: H04W 16/14 Spectrum sharing arrangements between different networks
• CPC Class Codes: H04W 24/10 Scheduling measurement reports ; Arrangements for measurement reports

Abstract

User equipment comprising a receiver obtains information about a set of channels to be sensed in a sensing process, wherein each channel is associated with a respective one of a number of radio frequencies. The receiver obtains a radio frequency signal by simultaneously sensing two or more of the channels included in the set of channels. A total power level of the sensed two or more channels is measured, and a comparison result is generated by comparing the total power level of the sensed two or more channels with a predetermined power level. The user equipment is controlled based on the comparison result. For example, if the total power level is below a threshold, then the sensed channels can be considered to not be in use by external transmission equipment.

Claims

1. A method of operating a user equipment comprising a receiver, the method comprising:

obtaining information about a set of channels to be sensed in a sensing process, wherein each channel is associated with a respective one of a plurality of radio frequencies;

operating the receiver to obtain a radio frequency signal by simultaneously sensing two or more of the channels included in the set of channels;

measuring a total power level of the sensed two or more channels;

generating a comparison result by comparing the total power level of the sensed two or more channels with a predetermined power level; and

controlling the user equipment based on the comparison result.

2. The method of claim 1, wherein controlling the user equipment based on the comparison result comprises:

for the duration of the sensing process, inhibiting further sensing of the two or more channels if the total power level of the sensed two or more channels is less than the predetermined power level.

3. The method of claim 1, wherein controlling the user equipment based on the comparison result comprises:

sensing the two or more channels by means of a different sensing process if the total power level of the sensed two or more channels is not less than the predetermined power level.

4. The method of claim 3, wherein the different sensing process comprises:

measuring a total power level of at least one but fewer than all of the sensed two or more channels; and

comparing the total power level of the at least one but fewer than all of the sensed two or more channels with the predetermined power level.

5. The method of claim 1, wherein:

the information about the set of channels to be sensed is information that defines a contiguous range of frequencies spanning a bandwidth large enough to be associated with two or more channels; and

operating the receiver to obtain a radio frequency signal by simultaneously sensing two or more of the channels included in the set of channels comprises operating the receiver to obtain a radio frequency signal by simultaneously sensing the contiguous range of frequencies spanning the bandwidth large enough to be associated with the two or more channels.

6. The method of claim 5, wherein controlling the user equipment based on the comparison result comprises:

for the duration of the sensing process, inhibiting further sensing of the contiguous range of frequencies spanning the bandwidth large enough to be associated with the two or more channels if the total power level of the sensed contiguous range of frequencies spanning the bandwidth large enough to be associated with the two or more channels is less than the predetermined power level.

7. The method of claim 6, comprising:

indicating that the contiguous range of frequencies spanning the bandwidth large enough to be associated with the two or more channels is not in use by external transmission equipment if the total power level of the sensed contiguous range of frequencies spanning the bandwidth large enough to be associated with the two or more channels is less than the predetermined power level.

8. The method of claim 5, wherein controlling the user equipment based on the comparison result comprises:

if the total power level of the contiguous range of frequencies spanning the bandwidth large enough to be associated with the two or more channels is not less than the predetermined power level, then dividing the contiguous range of frequencies spanning the bandwidth large enough to be associated with the two or more channels into two or more smaller contiguous ranges of frequencies, each spanning a bandwidth large enough to be associated with at least one channel; and

sensing whether each of the smaller contiguous ranges of frequencies is associated with a received power level that is less than a respective one of a plurality of lower predetermined power levels.

9. The method of claim 8, wherein:

at least one of the smaller contiguous ranges of frequencies spans a bandwidth large enough to be associated with two or more channels; and

the method comprises, for each of the smaller contiguous ranges of frequencies that span a bandwidth large enough to be associated with two or more channels, operating the receiver to obtain a radio frequency signal by simultaneously sensing the smaller contiguous range of frequencies spanning the bandwidth large enough to be associated with the two or more channels.

10. The method of claim 5, wherein controlling the user equipment based on the comparison result comprises:

if the total power level of the contiguous range of frequencies spanning the bandwidth large enough to be associated with the two or more channels is not less than the predetermined power level, then dividing the contiguous range of frequencies spanning the bandwidth large enough to be associated with the two or more channels into two or more smaller contiguous ranges of frequencies, each spanning a bandwidth large enough to be associated with at least one channel; and

sensing whether each of the smaller contiguous ranges of frequencies is associated with a received power level that is less than a predetermined power level.

11. The method of claim 10, wherein:

at least one of the smaller contiguous ranges of frequencies spans a bandwidth large enough to be associated with two or more channels; and

the method comprises, for each of the smaller contiguous ranges of frequencies that span a bandwidth large enough to be associated with two or more channels, operating the receiver to obtain a radio frequency signal by simultaneously sensing the smaller contiguous range of frequencies spanning the bandwidth large enough to be associated with the two or more channels.

12. The method of claim 1, comprising:

selecting the two or more channels to be simultaneously sensed by means of a selection process that includes determining that each of the two or more channels has a corresponding estimated channel power level below a predetermined threshold power level.

13. An apparatus for operating a user equipment comprising a receiver, the apparatus comprising:

circuitry configured to obtain information about a set of channels to be sensed in a sensing process, wherein each channel is associated with a respective one of a plurality of radio frequencies;

circuitry configured to operate the receiver to obtain a radio frequency signal by simultaneously sensing two or more of the channels included in the set of channels;

circuitry configured to measure a total power level of the sensed two or more channels;

circuitry configured to generate a comparison result by comparing the total power level of the sensed two or more channels with a predetermined power level; and

circuitry configured to control the user equipment based on the comparison result.

14. The apparatus of claim 13, wherein the circuitry configured to control the user equipment based on the comparison result comprises:

circuitry configured to inhibit further sensing of the two or more channels for the duration of the sensing process if the total power level of the sensed two or more channels is less than the predetermined power level.

15. The apparatus of claim 13, wherein the circuitry configured to control the user equipment based on the comparison result comprises:

circuitry configured to sense the two or more channels by means of a different sensing process if the total power level of the sensed two or more channels is not less than the predetermined power level.

16. The apparatus of claim 15, wherein the different sensing process comprises:

measuring a total power level of at least one but fewer than all of the sensed two or more channels; and

comparing the total power level of the at least one but fewer than all of the sensed two or more channels with the predetermined power level.

17. The apparatus of claim 13, wherein:

the information about the set of channels to be sensed is information that defines a contiguous range of frequencies spanning a bandwidth large enough to be associated with two or more channels; and

the circuitry configured to operate the receiver to obtain a radio frequency signal by simultaneously sensing two or more of the channels included in the set of channels comprises circuitry configured to operate the receiver to obtain a radio frequency signal by simultaneously sensing the contiguous range of frequencies spanning the bandwidth large enough to be associated with the two or more channels.

18. The apparatus of claim 17, wherein the circuitry configured to control the user equipment based on the comparison result comprises:

circuitry configured to inhibit further sensing of the contiguous range of frequencies spanning the bandwidth large enough to be associated with the two or more channels for the duration of the sensing process if the total power level of the sensed contiguous range of frequencies spanning the bandwidth large enough to be associated with the two or more channels is less than the predetermined power level.

19. The apparatus of claim 18, comprising:

circuitry configured to indicate that the contiguous range of frequencies spanning the bandwidth large enough to be associated with the two or more channels is not in use by external transmission equipment if the total power level of the sensed contiguous range of frequencies spanning the bandwidth large enough to be associated with the two or more channels is less than the predetermined power level.

20. The apparatus of claim 17, wherein the circuitry configured to control the user equipment based on the comparison result comprises:

circuitry configured to divide the contiguous range of frequencies spanning the bandwidth large enough to be associated with the two or more channels into two or more smaller contiguous ranges of frequencies, each spanning a bandwidth large enough to be associated with at least one channel, if the total power level of the contiguous range of frequencies spanning the bandwidth large enough to be associated with the two or more channels is not less than the predetermined power level; and

circuitry configured to sense whether each of the smaller contiguous ranges of frequencies is associated with a received power level that is less than a respective one of a plurality of lower predetermined power levels.

21. The apparatus of claim 20, wherein:

at least one of the smaller contiguous ranges of frequencies spans a bandwidth large enough to be associated with two or more channels; and

the apparatus comprises, circuitry configured to operate the receiver to obtain a radio frequency signal by simultaneously sensing the smaller contiguous range of frequencies spanning the bandwidth large enough to be associated with the two or more channels for each of the smaller contiguous ranges of frequencies that span a bandwidth large enough to be associated with two or more channels.

22. The apparatus of claim 17, wherein the circuitry configured to control the user equipment based on the comparison result comprises:

circuitry configured to divide the contiguous range of frequencies spanning the bandwidth large enough to be associated with the two or more channels into two or more smaller contiguous ranges of frequencies, each spanning a bandwidth large enough to be associated with at least one channel, if the total power level of the contiguous range of frequencies spanning the bandwidth large enough to be associated with the two or more channels is not less than the predetermined power level; and

circuitry configured to sense whether each of the smaller contiguous ranges of frequencies is associated with a received power level that is less than a predetermined power level.

23. The apparatus of claim 22, wherein:

at least one of the smaller contiguous ranges of frequencies spans a bandwidth large enough to be associated with two or more channels; and

the apparatus comprises circuitry configured to operate the receiver to obtain a radio frequency signal by simultaneously sensing the smaller contiguous range of frequencies spanning the bandwidth large enough to be associated with the two or more channels for each of the smaller contiguous ranges of frequencies that span a bandwidth large enough to be associated with two or more channels.

24. The apparatus of claim 13, comprising:

circuitry configured to select the two or more channels to be simultaneously sensed by means of a selection process that includes determining that each of the two or more channels has a corresponding estimated channel power level below a predetermined threshold power level.