Method and apparatus for dynamic spectrum sharing

• US 7,450,947 B2
• Filed: 06/21/2005
• Issued: 11/11/2008
• Est. Priority Date: 06/21/2005
• Status: Expired due to Fees

• Current Assignee: Motorola Solutions, Inc.
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Peterson, Roger L., Visotsky, Eugene, Kuffner, Stephen L.
• Primary Examiner(s): Anderson; Matthew
• Assistant Examiner(s): HUANG, WEN WU
• Application Number:
  US11/157,764
• Publication Number:
  US 20060286934A1
• Time in Patent Office: 1,239 Days
• Field of Search: 455/447, 455/448, 455 411- 3, 455/67.11, 455/13, 455/454, 455/41, 455/67
• US Class Current: 455/447
• CPC Class Codes: H04W 16/14 Spectrum sharing arrangements between different networks

Abstract

A technique for dynamic spectrum sharing includes identifying (705) a plurality of radio nodes (115, 120), measuring (710) a local signal value (SV) at each radio node (110, 200), and determining (715) a transmit decision. Each radio node can measure a local signal value (SV) of a protected transmission and the radio nodes are within a uniform SV region of the protected transmission. The transmit decision is determined for at least one of the plurality of radio nodes based on the SV of each radio node in the plurality of radio nodes and at least one threshold value that is related to statistical characteristics of the protected transmission at an interference boundary (105) of the protected transmission and a desired probability of non-interference with the protected transmission at the interference boundary.

Claims

1. A method for dynamic spectrum sharing, comprising:

identifying a plurality of radio nodes, for which plurality each radio node can measure a local signal value (local SV) of a protected transmission and for which plurality the radio nodes are within a uniform SV region of the protected transmission, wherein the local signal value is based on a signal power of the protected transmission at a radio node;

measuring the local SV at each radio node; and

determining a transmit decision for at least one of the plurality of radio nodes based on the local SV of each radio node in the plurality of radio nodes and at least one threshold value that is related to statistical characteristics of the protected transmission at an interference boundary of the protected transmission and a desired probability of non-interference with the protected transmission at the interference boundary, wherein the uniform SV region is a region within which a mean of the protected transmission power level over time at any two points within the region differs by no more than ±

6 db.

2. The method for dynamic spectrum sharing according to claim 1, wherein the determining of the transmit decision further comprises:

generating a spatial covariance matrix of the local SV measurements for the set of radio nodes;

determining an estimated signal value of the protected transmission in the uniform SV region based on the spatial covariance matrix and the local SV measurement at each radio node; and

comparing the estimated signal value of the protected transmission to one of the at least one threshold values to determine the transmit decision for the plurality of radio nodes.

3. The method for dynamic spectrum sharing according to claim 2, wherein the generation of the spatial covariance matrix of the local SV measurements further comprises determining distances between each distinct pair of radio nodes.

4. The method for dynamic spectrum sharing according to claim 2, wherein the estimated signal value is determined as

5. The method for dynamic spectrum sharing according to claim 2, wherein one of the at least one threshold values is determined as

6. The method for dynamic spectrum sharing according to claim 2, wherein the generating of the spatial covariance matrix of the local SV the determining of an estimated signal value of the protected transmission in the uniform SV region, and the determining of a transmit decision for the set of radio nodes are all performed in at least one radio node of the plurality of radio nodes.

7. The method for dynamic spectrum sharing according to claim 1, further comprising:

determining a binary local threshold decision at each radio node based on the local SV and one of the least one threshold values; and

comparing a summation of the binary local threshold decisions determined at each radio node to a numerical value to determine the transmit decision for the at least one of the plurality of radio nodes.

8. The method for dynamic spectrum sharing according to claim 7, wherein the at one of the at least one threshold values is determined as T=μ

−

σ

×

Q<sup>−

1</sup>((1−

P_D)^1/n), wherein μ and

sigma are, respectively, an estimated mean and an estimated standard deviation of the protected transmission within the uniform SV region, PD is the desired probability of non-interference with the protected transmission, and Q is the a Gaussian probability upper tail function.

9. The method for dynamic spectrum sharing according to claim 7, further comprising generating a spatial covariance matrix of the local SV measurements for the set of radio nodes, wherein the determining of one of the at least one threshold values is further based on the spatial covariance matrix.

10. An electronic device, comprising:

means for obtaining a set of local evaluations, wherein each local evaluation in the set of local evaluations is based on a signal value (SV) measurement of a protected transmission made by a radio node of a plurality of radio nodes, and wherein the plurality of radio nodes are within a uniform SV region of the protected transmission, and wherein the signal value is based on a signal power of the protected transmission at a radio node; and

means for determining a transmit decision for at least one of the plurality of radio nodes based on the set of local evaluations and at least one threshold value that is related to statistical characteristics of the protected transmission at an interference boundary of the protected transmission and a desired probability of non-interference with the protected transmission at the interference boundary, wherein the uniform SV region is a region within which a mean of the protected transmission power level over time at any two points within the region differs by no more than ±

6 db.

11. The electronic device according to claim 10, wherein the means for obtaining comprises:

a radio receiver that receives and decodes a set of messages that provide the set of local evaluations; and

a memory that stores the set of local evaluations.

12. The electronic device according to claim 10, wherein each local evaluation in the set of local evaluations is a local signal value measurement of the protected transmission made by a radio node of the plurality of radio nodes, and wherein the means for determining a transmit decision comprises:

a means for obtaining distances between each distinct pair of radio nodes;

a means for generating a spatial covariance matrix of the local SV measurements based on distances between each distinct pair of radio nodes a means for determining an estimated signal value of the protected transmission in the uniform SV region based on the spatial covariance matrix and the local SV measurement at each radio node; and

a means for determining the transmit decision for the plurality of radio nodes by comparing the estimated signal value of the protected transmission to one of the at least one threshold values.

13. The electronic device according to claim 12, further comprising a function that determines one of the at least one threshold values as

14. The electronic device according to claim 10, wherein each local evaluation is a binary local threshold decision that is a result of a comparison of the local SV measurement of, the protected transmission to one of the at least one threshold value, and wherein the means for determining a transmit decision bases the transmit decision on a binary combination of the set of local evaluations.

15. The electronic device according to claim 14, further comprising a function that determines the one of the at least one threshold values as T=μ

−

σ

×

Q<sup>−

1</sup>((1−

P_D)^1/n), wherein μ and

sigma are, respectively, an estimated mean and an estimated standard deviation of the protected transmission within the uniform SV region, PD is the desired probability of non-interference with the protected transmission, and Q is a Gaussian probability upper tail function.

16. A processor having a set of program instructions stored therein for controlling the processor to perform dynamic spectrum sharing, the set of program instructions comprising:

instructions for identifying a plurality of radio nodes, for which plurality each radio node can measure a local signal value (local SV) of a protected transmission and for which plurality the radio nodes are within a uniform SV region of the protected transmission, wherein the local signal value is based on a signal power of the protected transmission at a radio node;

instructions for measuring the local SV at each radio node; and

instructions for determining a transmit decision for at least one of the plurality of radio nodes based on the local SV of each radio node in the plurality of radio nodes and at least one threshold value that is related to statistical characteristics of the protected transmission at an interference boundary of the protected transmission and a desired probability of non-interference with the protected transmission at the interference boundary, wherein the uniform SV region is a region within which a mean of the protected transmission power level over time at any two points within the region differs by no more than ±

6 db.