Method and system for obtaining an idle spectrum

• US 9,071,345 B2
• Filed: 03/27/2012
• Issued: 06/30/2015
• Est. Priority Date: 06/02/2011
• Status: Active Grant

• Current Assignee: Datang Mobile Communications Equipment Company Limited (China Information Communication Technology Group Co. Ltd.)
• Original Assignee: China Academy of Telecom Technology (China Information Communication Technology Group Co. Ltd.)
• Inventors: Bai, Wenling, Jiang, Chenggang, Li, Yuanyuan, Yang, Yu
• Primary Examiner(s): Kasraian, Allahyar
• Application Number:
  US14/122,618
• Publication Number:
  US 20140185653A1
• Time in Patent Office: 1,190 Days
• Field of Search: 455/434, 455450-455, 4554561-457, 455507-516, 455/179.1, 455/180.1, 455/185.1, 4551151-1154
• US Class Current: 1/1
• CPC Class Codes: H04B 1/713 using frequency hopping
• CPC Class Codes: H04B 17/27 for locating or positioning the transmitter
• CPC Class Codes: H04L 27/0006 Assessment of spectral gaps suitable for allocating digitally modulated signals, e.g. for carrier allocation in cognitive radio for spectrum sharing between different networks H04W16/14
• CPC Class Codes: H04W 16/14 Spectrum sharing arrangements between different networks
• CPC Class Codes: H04W 28/16 Central resource management; Negotiation of resources or communication parameters, e.g. negotiating bandwidth or QoS [Quality of Service]
• CPC Class Codes: H04W 52/0219 where the power saving management affects multiple terminals
• CPC Class Codes: H04W 52/0245 according to signal strength
• CPC Class Codes: H04W 84/18 Self-organising networks, e.g. ad-hoc networks or sensor networks
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

The present disclosure provides a method and an apparatus for obtaining an idle spectrum. The method includes: obtaining, by a central management unit, configuration information of a transmitter of an authorized system, and obtaining geographic location information of candidate sense nodes; selecting, by the central management unit, sense nodes from the candidate sense nodes according to the configuration information and the geographic location information, and informing the selected sense nodes to perform spectrum sensing; and receiving, by the central management unit, sensing results of the selected sense nodes, and obtaining information of an idle spectrum according to the sensing results.

Claims

1. A method for obtaining an idle spectrum, comprising:

obtaining, by a central management unit, configuration information of a transmitter of an authorized system, and obtaining geographic location information of candidate sense nodes;

wherein the configuration information comprises;

geographic location information of the transmitter of the authorized system, spectrum information of the transmitter of the authorized system and transmission power information of the transmitter of the authorized system;

selecting, by the central management unit from the candidate sense nodes, a designated number of sense nodes which are closest to the transmitter of the authorized system from the candidate sense nodes according to the configuration information and the geographic location information, and informing the selected sense nodes to perform spectrum sensing; and

receiving, by the central management unit, sensing results of the selected sense nodes, and obtaining information of an idle spectrum according to the sensing results;

wherein the obtaining the information of the idle spectrum according to the sensing results comprises;

combining, by the central management unit, the sensing results and determining whether the authorized system is currently transmitting signals on the spectrum; and

obtaining, by the central management unit, the information of the idle spectrum for a request node according to an idle spectrum request message of the request node and a determination result on whether the authorized system is currently transmitting signals on the spectrum;

wherein the idle spectrum request message carries maximum transmission power information of the request node;

the obtaining the information of the idle spectrum for the request node according to the idle spectrum request message of the request node and the determination results on whether the authorized system is currently transmitting signals on the spectrum comprises;

if the request node transmit using the maximum transmission power, calculating, by the central management unit, an interference level suffered by the authorized system transmitting on the spectrum;

if the interference level is lower than a preconfigured threshold, determining, by the central management unit, that the spectrum is not idle;

otherwise, determining, by the central management unit, that the spectrum is not idle.

2. The method of claim 1, wherein the configuration information comprises any one or any combination of:

geographic location information of the transmitter of the authorized system, spectrum information of the transmitter of the authorized system, and transmission power information of the transmitter of the authorized system;

the obtaining the configuration information of the transmitter of the authorized system comprises;

obtaining, by the central management unit, the configuration information through accessing a database, or through a spectrum measurement manner, or via assistance of the authorized system.

3. The method of claim 1, wherein the obtaining the geographic location information of the candidate sense nodes comprises:

receiving, by the central management unit, the geographic location information reported by each candidate sense node;

wherein each candidate sense node obtains its geographic location information by a geographic locating manner.

4. The method of claim 1, wherein

the selecting the designated number of sense nodes which are closet to the transmitter of the authorized system from the candidate sense nodes according to the configuration information and the geographic location information comprises:

calculating, by the central management unit, a maximum propagation loss L_max between the candidate sense nodes and the transmitter of the authorized system according to the transmitter power information P_S of the transmitter of the authorized system and a detecting threshold P_T;

calculating, by the central management unit, a maximum distance d_max between the candidate sense nodes and the transmitter of the authorized system according to the maximum propagation loss L_max; and

selecting, by the central management unit, the designated number of sense nodes which are closet to the transmitter of the authorized system from the candidate sense nodes for the transmitter of the authorized system according to the geographic location information of the transmitter of the authorized system, the geographic location information of the candidate sense nodes and the maximum distance d_max.

5. The method of claim 4, wherein the calculating the maximum propagation loss L_max between the candidate sense nodes and the transmitter of the authorized system according to the transmission power information P_S and the detecting threshold P_T comprises:

calculating, by the central management unit, L_max[dB]=P_S[dB]−

P_T[dB];

the calculating the maximum distance d_max between the candidate sense nodes and the transmitter of the authorized system according to the maximum propagation loss L_max comprises;

calculating, by the central management unit, d_max through solving W(d_max)=L_max, wherein W(.) denotes a wireless channel propagation model function.

6. The method of claim 4, wherein the selecting the designated number of sense nodes which are closet to the transmitter of the authorized system for the transmitter of the authorized system according to the geographic location information of the transmitter of the authorized system, the geographic location information of the candidate location information and the maximum distance d_max comprises:

selecting, by the central management unit, the designated number of candidate sense nodes closest to the transmitter of the authorized system from the candidate sense nodes which have a distance not larger than d_max from the transmitter of the authorized system.

7. The method of claim 1, wherein the idle spectrum request message carries geographic location information of the request node;

the obtaining the information of the idle spectrum for the request node according to the idle spectrum request message of the request node and the determination result on whether the authorized system is currently transmitting signals on the spectrum comprises;

calculating, by the central management unit, a geographic distance d between the transmitter of the authorized system and the request node according to the geographic location information of the transmitter of the authorized system and the geographic location information of the request node;

calculating, by the central management unit, a receiving signal strength P_R from the transmitter of the authorized system to the request node to according to geographic distance d; and

if the receiving signal strength P_R is lower than a detecting threshold P_T, determining, by the central management unit, that the spectrum is idle;

otherwise, determining, by the central management unit, that the spectrum is not idle.

8. The method of claim 7, wherein the calculating the receiving signal strength P_R from the transmitter of the authorized system to the request node according to the geographic distance d comprises:

calculating, by the central management unit, P_R[dB]=P_S[dB]−

L[dB], wherein L=W(d), W(.) denotes a wireless channel propagation model function, P_S denotes the power transmission information.

9. The method of claim 1, wherein the idle spectrum request message carries a list of spectrums supported by the request node;

the obtaining the information of the idle spectrum for the request node according to the idle spectrum request message of the request node and the determination result on whether the authorized system is currently transmitting signals on the spectrum comprises;

determining, by the central management unit, a target spectrum set according to the list of spectrums supported by the request node, and determining whether each spectrum in the target spectrum set is idle.

10. An apparatus for obtaining an idle spectrum, comprising:

one or more processors;

a memory; and

one or more program modules stored in the memory and to be executed by the one or more processors, the one or more program modules comprise;

a first obtaining module, adapted to obtain configuration information of a transmitter of an authorized system and obtain geographic location information of candidate sense nodes;

wherein the configuration information comprises;

geographic location information of the transmitter of the authorized system;

spectrum information of the transmitter of the authorized system and transmission power information of the transmitter of the authorized system;

a selecting module, adapted to select a designated number of the sense nodes which are closet to the transmitter of the authorized system according to the configuration information and the geographic location information;

a transmitting module, adapted to inform the sense nodes to perform spectrum sensing;

a receiving module, adapted to receive sensing results of the sense nodes; and

a second obtaining module, adapted to determine information of an idle spectrum according to the sensing results;

wherein the second obtaining module is adapted to combine the sensing results to determine whether the authorized system is transmitting signals on the spectrum and obtain information of the idle spectrum according to an idle spectrum request message of a request node and a determination result on the authorized system is currently transmitting signals on the spectrum;

the idle spectrum request message carries the maximum transmission power of the request node;

the second obtaining modules is further adapted to

calculate, if the request node transmits using the maximum transmission power, an inference level suffered by the authorized system which is transmitting signals on the spectrum,

determine that the spectrum is idle if the interference level is lower than a predefined threshold; and

determine the spectrum is not idle if otherwise.

11. The apparatus of claim 10, wherein the selecting module is further adapted to

calculate a maximum propagation loss L_max between the candidate sense nodes and the transmitter of the authorized system according to the configured transmission power information P_S of the transmitter of the authorized system and a detecting threshold P_T;

calculate a maximum distance d_max between the candidate sense nodes and the transmitter of the authorized system according to the maximum propagation loss L_max;

select sense nodes for each transmitter of the authorized system according to the geographic location information of the transmitter of the authorized system, the geographic location information of each candidate sense node and the maximum distance d_max.

12. The apparatus of claim 11, wherein

the selecting module is further adapted to calculate L_max [dB]=P_S [dB]−

P_T[dB], and calculate d_max through solving W(d_max)=L_max, wherein W(.) denotes a function of a wireless channel propagation model.

13. The apparatus of claim 11, wherein

the selecting module is further adapted to select, from candidate sense nodes having a distance not larger than d_max from the transmitter of the authorized system, the designated number of candidate sense nodes most close to the transmitter of the authorized system as sense nodes.

14. The apparatus of claim 10, wherein the idle spectrum request message carries the geographic location information of the request node;

the second obtaining module is further adapted to

calculate a geographic distance d between the transmitter of the authorized system and the request node according to the geographic location information of the request node and the geographic location information of the transmitter of the authorized system which is transmitting signals on the spectrum;

calculate a receiving signal strength P_R from the transmitter of the authorized system to the request node according to the geographic distance d;

determine, if the receiving signal strength P_R is lower than a detecting threshold P_T, that the spectrum is idle; and

determine that the spectrum is not idle if otherwise.

15. The apparatus of claim 14, wherein

the second obtaining module is further adapted to calculate P_R[dB]=P_S[dB]−

L[dB], L=W(d);

wherein W(.) is a function of the wireless channel propagation model, P_S denotes the configured transmission power information.

16. The apparatus of claim 10, wherein the idle spectrum request message carries a list of spectrums supported by the request node;

the second obtaining module is further adapted to determine a target spectrum set according to the supported spectrum list and determine whether each spectrum in the target spectrum set is idle.