CN101908934A - Frequency spectrum sensing method, device and equipment of frequency spectrum sharing system - Google Patents

Abstract

The embodiment of the invention provides frequency spectrum sensing method, device and equipment of a frequency spectrum sharing system. The detection of the frequency spectrum sensing energy is carried out in a frequency domain; a whole frequency band is divided into a plurality of subbands; and a local sensing node measures the energy level of each subband and feeds back the energy level of each subband to a confluence center. Aiming at each subband, in all sensing nodes, the confluence center selects the energy level of the subband with a maximum energy level as the global energy level of the subband, and the energy levels of the subbands with the maximum value are averaged to obtain the global energy level of the whole frequency band. By using the cooperative sensing method, more local sensed information is sent to the confluence center, the maximum energy level of each subband can be selected among all cooperative sensing nodes, and the energy level of the deeply selectively faded subband does not contribute to the global energy level. By the mode, more user subsets can be obtained, the selective fade of the frequency is reduced, and the sensing performances are improved.

Description

The frequency spectrum sensing method of spectra sharing system, device and equipment

Technical field

The present invention relates to the communication technology, relate in particular to frequency spectrum sensing method, device and the equipment of spectra sharing system.

Background technology

Authorize in the frequency spectrum spectra sharing system down, main system and from the shared a certain frequency spectrum resource of system, when main system does not take this frequency spectrum resource, can this idling-resource of opportunistic use from system.Main system has privilege to the use of frequency spectrum, can insert at any time.From system is opportunistic use frequency spectrum, when main system is used this frequency spectrum, need dodge from system.For fear of main system is produced harmful interference, from the necessary periodic existence that detects main system of system, promptly periodically whether the perceived spectral resource is available for subsystem.If main system does not take this frequency spectrum resource, subsystem can use this frequency spectrum resource; When main system takies this frequency spectrum resource, subsystem just can not use this frequency spectrum resource.For improving the availability of frequency spectrum, subsystem should be found idle frequency spectrum as much as possible, and on the other hand, subsystem should be avoided main system is produced harmful interference.This frequency spectrum perception that just requires subsystem must be reliable.Therefore, frequency spectrum perception is the most basic requirement to spectrum systems, and accurate frequency spectrum perception is the basis that subsystem effectively inserts frequency spectrum, and frequency spectrum perception then can be avoided producing harmful interference to main system reliably.

Yet in real spectra sharing system environment, because main signal is often faint, frequency spectrum perception always is subjected to the influence of uncertain interference, fading channel, shade etc.For accuracy and the reliability that improves frequency spectrum perception, collaboration type frequency spectrum perception technology has been proposed.General frequency spectrum perception technology relies on single sensing node, and collaboration type frequency spectrum perception technology is then utilized a plurality of sensing nodes.In the collaboration type frequency spectrum perception technology, a plurality of sensing nodes are carried out sub-clustering, and when carrying out sub-clustering, the node that the geographical position is closed on mutually forms one bunch, with the identical main system signal of the cooperation sensing node perception of cluster,, the main system signal just arrives different sensing nodes although going through different paths.Sensing node in bunch must guarantee identical frequency spectrum judging result, otherwise sub-clustering will be inaccurate, need carry out sub-clustering again.With the distributed sensing node in the cluster perception report is fed back to fusion center (being generally the base station), fusion center merges these perception reports according to predetermined rule then, and makes the overall frequency spectrum judging of this bunch in view of the above.If the enough accurate words of perception, the frequency spectrum judging of all sensing nodes in same bunch is identical.How effectively to be used to has influenced perceptual performance to a great extent from the perception report of distributed sensing node.Therefore how to utilize the perception information of a plurality of sensing nodes to reach more accurate more reliable perception spectra sharing system is become extremely important.

One of existing best cooperation cognition technology is a distributed energy level Merge Scenarios.In this cooperation aware scheme, each sensing node (also claiming local sensing node) applied energy in cognitive method detects, energy detection method is a kind of simple frequency spectrum sensing method, it detects the energy of certain frequency spectrum, if detected energy is higher than certain predetermined threshold value, just think that this frequency spectrum is occupied, otherwise this frequency spectrum is idle.Based on energy measuring, i sensing node measure its in whole bandwidth energy rank Ei and feed back to fusion center, in fusion center, thereby on average the energy rank collected of all sensing nodes obtains a total energy rank:

$E_{\mathrm{Global}}=\frac{1}{N}\underset{i=1}{\overset{N}{\mathrm{\Σ}}}{E}_i$

Wherein N is the quantity of cooperation sensing node.With total energy rank E _GlobalCompare with a predetermined thresholding T, if E _Global〉=T, then total frequency spectrum judging is to have the main system signal in the current shared system, if E _Global〉=T, then total frequency spectrum judging is not have the main system signal in the current shared system.Thresholding T is by false alarm rate P _FADecision.False alarm rate is existing well definition in etection theory, does not here go to live in the household of one's in-laws on getting married and chats.The schematic diagram of above-mentioned existing cooperation aware scheme as shown in Figure 1.

Summary of the invention

For solving above-mentioned shortcoming of the prior art, the present invention proposes frequency spectrum sensing method, device and the equipment of new spectra sharing system.

According to the present invention, the energy measuring in the frequency spectrum perception is carried out at frequency domain, and whole frequency band is divided into a plurality of subbands, and local sensing node is measured the energy rank of each subband and the energy rank of each subband is fed back to fusion center.At each subband, in all sensing nodes, fusion center is selected the global energy rank of other sub belt energy rank of ceiling capacity level as this subband, by all peaked sub belt energy ranks are asked on average, draws the global energy rank of whole frequency band.

Particularly, according to an embodiment of the invention, provide a kind of frequency spectrum sensing method of spectra sharing system, described spectra sharing system comprises main system and from system, comprises the base station from system, fusion center and sensing node, and described method comprises,

The perception request is initiated in the base station;

Sub-clustering is carried out to the sensing node in the sub-district in the base station, and the energy measuring thresholding that is provided with bunch is provided with the frequency spectrum perception parameter, and frequency band division is become a plurality of subbands;

Base station broadcast frequency spectrum perception parameter;

Sensing node is carried out energy measuring, measures the energy rank of all subbands at frequency domain, and the energy rank of all subbands is reported to fusion center;

Fusion center receives the energy rank report of sensing node, and the energy rank of all subbands of the sensing node report of same cluster is merged, the global energy rank that draws bunch;

Fusion center will bunch the energy measuring thresholding of global energy rank and this bunch compare the frequency spectrum judging that draws this bunch: if the global energy rank is greater than the energy measuring thresholding of this bunch, then judge on the frequency band of this bunch and have the main system signal, if less than the energy measuring thresholding of this bunch, then judging on the frequency band of this bunch, the global energy rank do not have the main system signal.

According to an optional embodiment of the present invention, wherein, the frequency spectrum perception parameter includes but not limited to sub band number N _Sub, detecting period, N _SubFor greater than 1 natural number.

According to an optional embodiment of the present invention, wherein, described fusion center merges the energy rank of all subbands of the sensing node of same cluster report, and the global energy rank that draws bunch is meant:

To compare with the sub belt energy rank of m subband of each sensing node of cluster, select the global energy rank of maximum sub belt energy rank, m=1...N as this m subband _Sub

Fusion center is with N _SubThe global energy rank of individual subband averages, and draws the global energy rank of this bunch.

According to an optional embodiment of the present invention, preferred, described fusion center can be the base station, and described sensing node can be an end user device.

According to an embodiment of the invention, a kind of frequency spectrum perception management devices is provided, be operated in spectra sharing system from system, the described base station that from system, comprises, sensing node, described device comprises:

Initiate the unit, be used to initiate the frequency spectrum perception request;

The unit is set, is used for the sensing node sub-clustering, the energy measuring thresholding that is provided with bunch further, is provided with the unit and also is used to be provided with the frequency spectrum perception parameter, and frequency band division is become a plurality of subbands;

Transmitting element is used for to sensing node broadcast spectrum perceptual parameters.

According to an optional embodiment of the present invention, described frequency spectrum perception parameter includes but not limited to sub band number N _Sub, detecting period, N _SubFor greater than 1 natural number.

According to an optional embodiment of the present invention, preferred, described device can be installed in the base station.

According to an embodiment of the invention, provide a kind of frequency spectrum perception to converge device, the described device that converges comprises

Receiving element is used to receive the energy rank report from all subbands of sensing node;

Judging unit, be used to judge sensing node bunch, will with bunch the energy rank of all subbands of sensing node be classified as a set;

The subband selected cell, be used for with bunch the energy rank of m subband of each sensing node compare, select the global energy rank of maximum sub belt energy rank, m=1...N as this m subband _Sub, N _SubBeing the sub band number of frequency band, is the natural number greater than 1;

Computing unit is used for N _SubThe global energy rank of individual subband averages, and draws the global energy rank of this bunch;

Decision unit, be used for will bunch the energy measuring thresholding of global energy rank and this bunch compare the frequency spectrum judging that draws this bunch: if the global energy rank is greater than the energy measuring thresholding of this bunch, then judge on the frequency band of this bunch and have the main system signal, if less than the energy measuring thresholding of this bunch, then judging on the frequency band of this bunch, the global energy rank do not have the main system signal.

According to an optional embodiment of the present invention, preferred, the described device that converges can be installed in the base station.

According to an embodiment of the invention, a kind of base station is provided, described base station comprises that above-mentioned frequency spectrum perception management devices and above-mentioned frequency spectrum perception converge device.

According to an embodiment of the invention, a kind of frequency spectrum sensing device is provided, comprise

Receiving element is used for the received spectrum perceptual parameters, comprises sub band number N _SubAnd detecting period, N _SubFor greater than 1 natural number;

Energy detection unit is used for perceived spectral, carries out energy measuring, measures the energy rank of all subbands at frequency domain;

Feedback unit is used to feed back the energy rank of all subbands.

According to an optional embodiment of the present invention, preferred, described device is installed on the end user device.

Utilize cooperation cognitive method of the present invention, more local perception information sends to fusion center, can help fusion center to make more accurate perception judges, and the ceiling capacity rank of each subband is selected between all cooperation sensing nodes, by this mode, can obtain multi-user diversity, reduce frequency selective fading, improve perceptual performance.

Description of drawings

By below in conjunction with the description of the drawings, and along with understanding more comprehensively to of the present invention, other purposes of the present invention and effect will become clear more and easy to understand, wherein:

Fig. 1 represents the schematic diagram of existing cooperation aware scheme.

Fig. 2 represents the cooperation aware scheme schematic flow sheet that utilizes multi-user diversity according to an embodiment of the invention.

Fig. 3 represents the subband selection course schematic diagram according to an embodiment of the invention.

Fig. 4 represents the cooperation aware scheme schematic diagram that utilizes multi-user diversity according to an embodiment of the invention.

Fig. 5 represents the frequency spectrum perception management devices structural representation according to an embodiment of the invention.

Fig. 6 represents to converge the apparatus structure schematic diagram according to the frequency spectrum perception of an embodiment of the invention.

Fig. 7 represents the architecture of base station schematic diagram according to an embodiment of the invention.

Fig. 8 represents the frequency spectrum sensing device structural representation according to an embodiment of the invention.

Fig. 9 represents to survey according to omission of the present invention the performance simulation result schematic diagram of probability and sub band number.

Figure 10 represents to survey probability and signal-to-noise performance simulation result schematic diagram according to omission of the present invention.

In all above-mentioned accompanying drawings, identical label represents to have identical, similar or corresponding feature or function.

Embodiment

Specifically describe embodiments of the present invention below in conjunction with accompanying drawing.

Embodiments of the present invention realize based on spectra sharing system, are the description aspect, are example with the system of IEEE802.22 standard criterion, and spectra sharing system has multiple, and can both be applied to the present invention.Above-mentioned setting only is an exemplary illustration.

According to the present invention, the cooperation perception utilizes multi-user diversity to obtain frequency spectrum perception performance better.According to the cooperation aware scheme schematic flow sheet that utilizes multi-user diversity of an embodiment of the invention as shown in Figure 2, in the present embodiment, preferred, the base station is as frequency spectrum perception administrative center and frequency spectrum perception fusion center, end user device is as local sensing node.But the present invention is not limited thereto, it will be understood by those of skill in the art that the network side equipment in the subsystem, rationally is provided with through system, can be as frequency spectrum perception administrative center and/or frequency spectrum perception fusion center.

Concrete, at step S201 place, the frequency spectrum perception request is initiated in the base station, and the perception request is initiated perception once generally by the well-regulated initiation of BS such as each superframe.

At step S202 place, sub-clustering is carried out based on predetermined rule in the base station, and the local sensing node that the geographical position is closed on mutually forms one bunch, the energy measuring thresholding that is provided with bunch, the perceptual parameters that is provided with bunch: the sub band number N that comprises frequency band _Sub, detecting period etc., wherein N _SubFor greater than 1 natural number, detecting period refers to be used for the time interval of perceived spectral, and as a rule, the frequency spectrum perception time is long more, and perceived accuracy is high more, but the perception expense is also big more; Same, subband is cut apart many more, and the information of perception is many more, can bring higher multi-user diversity gain, but subband is many more, and transport overhead also increases.Spectra sharing system should rationally be provided with perceptual parameters according to concrete running situation.

At step S203 place, the base station comprises the sub band number N of frequency band to local sensing node broadcasting perceptual parameters _Sub, detecting period etc.

At step S204 place, local sensing node is carried out frequency spectrum perception, carries out energy measuring: measure all N _SubIndividual subband is at the energy rank of frequency domain, E _{I, m}Expression is from the energy rank of m subband of i local sensing node, and i=1...N represents the local sensing node number in this bunch, m=1...N _Sub, represent the sub band number of this bunch frequency band, same bunch local sensing results such as formula (1) expression:

$E=\left[\begin{array}{cccc}{\mathrm{<figure-callout\; id="1"\; label="E"\; filenames="H2009100526529E0000071.png"\; state="\{\{state\}\}">E</figure-callout>}}_{\mathrm{1,1}}& {\mathrm{<figure-callout\; id="1"\; label="E"\; filenames="H2009100526529E0000071.png"\; state="\{\{state\}\}">\; <figure-callout\; id="2"\; label="E"\; filenames="H2009100526529E0000031.png,H2009100526529E0000071.png"\; state="\{\{state\}\}">E</figure-callout>\; </figure-callout>}}_{\mathrm{1,2}}& ...& {\mathrm{<figure-callout\; id="1"\; label="E"\; filenames="H2009100526529E0000071.png"\; state="\{\{state\}\}">E</figure-callout>}}_{1,{\mathrm{<figure-callout\; id="2"\; label="N\; sub\; E"\; filenames="H2009100526529E0000031.png,H2009100526529E0000071.png"\; state="\{\{state\}\}">N</figure-callout>}}_{\mathrm{sub}}}& \\ E_{}{}_{\mathrm{2,1}}& {\mathrm{<figure-callout\; id="2"\; label="E"\; filenames="H2009100526529E0000031.png,H2009100526529E0000071.png"\; state="\{\{state\}\}">\; <figure-callout\; id="2"\; label="E"\; filenames="H2009100526529E0000031.png,H2009100526529E0000071.png"\; state="\{\{state\}\}">E</figure-callout>\; </figure-callout>}}_{\mathrm{2,2}}& ...& {\mathrm{<figure-callout\; id="2"\; label="E"\; filenames="H2009100526529E0000031.png,H2009100526529E0000071.png"\; state="\{\{state\}\}">E</figure-callout>}}_{2,N_{\mathrm{sub}}}\\ & ...& & \\ E_{N,1}& E_{N,2}& ...& E_{N,N_{\mathrm{sub}}}\end{array}\right]---\left(1\right)$

At step S205 place, local sensing node is the energy rank E of each subband with the frequency spectrum perception result _{I, m}Feed back to fusion center, fusion center is generally the base station.

At step S206 place, the base station is based on all sub belt energy ranks of all local sensing nodes of receiving, selection will with bunch the energy rank of m subband of all N sensing node compare, select the global energy rank E of maximum sub belt energy rank as m the subband of this bunch _m, m=1...N _Sub, N _SubBe the sub band number of frequency band, formulate is as follows:

$E_m=\underset{i}{\max }\left\{E_{i,m}\right\}$ i＝1...N (2)

The sensing node number of N in being bunch wherein.

The process that step S206 place carries out also claims the subband selection course, will be described in detail this process below.After subband was selected, the base station obtained the global energy rank of all subbands.

At step S207 place, the base station by to bunch the global energy rank of all subbands ask on average the global energy rank E of the whole frequency band that obtains bunch _Global:

$E_{\mathrm{Global}}=\frac{1}{N_{\mathrm{sub}}}\underset{m=1}{\overset{N_{\mathrm{sub}}}{\mathrm{\&Sigma;}}}{E}_m---\left(3\right)$

At step S208 place, frequency spectrum judging is carried out in the base station, with E _GobalCompare with a predetermined thresholding.Thresholding T such as formula (4) definition:

$T=P_N[1+\frac{Q^{-1}\left(P_{\mathrm{FA}}\right)}{\sqrt{M}}]---\left(4\right)$

P wherein _NBe noise power, M is the hits that obtains, P _FAFalse alarm rate, Q (x) is the tail probability of normalization zero-mean Gaussian random variable

$Q\left(x\right)=\frac{1}{\sqrt{2\mathrm{\&pi;}}}{\&Integral;}_x^{\&infin;}{e}^{-{\mathrm{<figure-callout\; id="2"\; label="t"\; filenames="H2009100526529E0000031.png,H2009100526529E0000071.png"\; state="\{\{state\}\}">t</figure-callout>}}^2/2}\mathrm{dt}---\left(5\right)$

If E _Global〉=T, then making total frequency spectrum judging at step S209 place is to have the main system signal in the current shared system, if E _Global＜T, then making total frequency spectrum judging at step S210 place is not have the main system signal in the current shared system.

Describe the subband selection course in detail below in conjunction with Fig. 3.

The exemplary expression of Fig. 3 has the subband selection course of two sensing nodes.At local sensing node 1, the energy rank measured value of all subbands is expressed as:

$\begin{array}{cccc}{\mathrm{<figure-callout\; id="1"\; label="E"\; filenames="H2009100526529E0000071.png"\; state="\{\{state\}\}">E</figure-callout>}}_{\mathrm{1,1}}& {\mathrm{<figure-callout\; id="1"\; label="E"\; filenames="H2009100526529E0000071.png"\; state="\{\{state\}\}">\; <figure-callout\; id="2"\; label="E"\; filenames="H2009100526529E0000031.png,H2009100526529E0000071.png"\; state="\{\{state\}\}">E</figure-callout>\; </figure-callout>}}_{\mathrm{1,2}}& ...& {\mathrm{<figure-callout\; id="1"\; label="E"\; filenames="H2009100526529E0000071.png"\; state="\{\{state\}\}">E</figure-callout>}}_{1,N_{\mathrm{sub}}}\end{array}$ (6)

At local sensing node 2, the energy rank measured value of all subbands is expressed as:

$\begin{array}{cccc}{\mathrm{<figure-callout\; id="2"\; label="E"\; filenames="H2009100526529E0000031.png,H2009100526529E0000071.png"\; state="\{\{state\}\}">E</figure-callout>}}_{\mathrm{2,1}}& {\mathrm{<figure-callout\; id="2"\; label="E"\; filenames="H2009100526529E0000031.png,H2009100526529E0000071.png"\; state="\{\{state\}\}">\; <figure-callout\; id="2"\; label="E"\; filenames="H2009100526529E0000031.png,H2009100526529E0000071.png"\; state="\{\{state\}\}">E</figure-callout>\; </figure-callout>}}_{\mathrm{2,2}}& ...& {\mathrm{<figure-callout\; id="2"\; label="E"\; filenames="H2009100526529E0000031.png,H2009100526529E0000071.png"\; state="\{\{state\}\}">E</figure-callout>}}_{2,N_{\mathrm{sub}}}\end{array}$ (7)

The energy rank measured value of each subband is different.Because the transmission of main system signal arrives each sensing node through different paths, go through different frequency selective fadings, at each sensing node, the frequency response of measurement is also different.To first subband,

max{E _1，1，E _2，1}＝E _2，1 (8)

The global energy rank of first subband is E so _2,1.Other subbands are also followed above-mentioned rule and are selected its global energy rank.By the present invention, can obtain multi-user diversity gain, reduce frequency selective fading, because the ceiling capacity rank of each subband is selected between all cooperation sensing nodes, the sub belt energy rank of simultaneously dark selectivity decline is not made contributions to the global energy rank.This also is the main reason that the present invention has better perceptual performance.

Fig. 4 has provided the cooperation aware scheme schematic diagram that utilizes multi-user diversity according to an embodiment of the invention:

In wireless environment, same bunch N local sensing node is generally end user device, according to the perceptual parameters of default, carries out local perception, carries out the frequency domain energy measuring, measures the energy rank of each subband.Then, each local sensing node with local sensing results promptly the energy rank of all subbands feed back to fusion center.Fusion center is generally the base station, carries out subband and selects, and draws the global energy rank of each subband, asks on average by the global energy rank to all subbands, obtains the global energy rank of whole frequency band.Based on the global energy rank of whole frequency band, frequency spectrum judging is carried out in the base station.

Fig. 5 has provided the frequency spectrum perception management devices structural representation according to an embodiment of the invention.

In the embodiments of the present invention, frequency spectrum perception management devices 500 is used to initiate the frequency spectrum perception request, and parameter is set comprises the frequency spectrum perception parameter, and the broadcast spectrum perceptual parameters.Frequency spectrum perception management devices 500 comprises initiates unit 501, and unit 502 and transmitting element 503 are set.General, frequency spectrum perception management devices 500 can be installed in the base station, also can be installed in other wireless network management devices.

Concrete, to initiate unit 501 and be configured to initiate the frequency spectrum perception request, the frequency spectrum perception request is initiated perception once generally by the well-regulated initiation of frequency spectrum perception management devices such as each superframe.

Unit 502 is set in a single day receives the frequency spectrum perception request, just with the local sensing node in the sub-district, be generally the end user device sub-clustering, the principle front of sub-clustering is existing to be described, and repeats no more here.Be provided with the unit with local sensing node sub-clustering after, the energy measuring thresholding that is provided with bunch; Further, the frequency spectrum perception parameter is set, comprises spectrum division is become a plurality of subbands, sub band number is N _Sub, also comprise detecting period.N wherein _SubFor greater than 1 natural number, detecting period refers to be used for the time interval of perceived spectral, and as a rule, the frequency spectrum perception time is long more, and perceived accuracy is high more, but the perception expense is also big more; Same, subband is cut apart many more, and the information of perception is many more, can bring higher multi-user diversity gain, but subband is many more, and transport overhead also increases.Spectra sharing system should rationally be provided with perceptual parameters according to concrete running situation.

Transmitting element 503 is configured to comprise that with the parameter that unit 502 sets is set the frequency spectrum perception parameter sends to local perception center with the form of broadcasting.

Fig. 6 provides according to the frequency spectrum perception of an embodiment of the invention and converges the apparatus structure schematic diagram.

In the embodiments of the present invention, frequency spectrum perception is converged the sensing results report that device 600 is used to receive local sensing node feedback, the i.e. energy rank of all subbands report is carried out the subband selection and is drawn the global energy rank, carries out frequency spectrum judging based on the global energy rank.Frequency spectrum perception is converged device 600 and is comprised receiving element 601, judging unit 602, subband selected cell 603, computing unit 604, decision unit 605 and memory cell 606.General, frequency spectrum perception is converged device 600 and can be installed in the base station, also can be installed in other wireless network management devices.

Concrete, receiving element 601 is configured to receive from the energy rank report of all subbands of sensing node and is stored in memory cell 606.

Judging unit 602 is configured to the information according to receiving element 601, judge sensing node bunch, and the data of reading cells 606 storage in view of the above, will with bunch the energy rank of all subbands of sensing node be classified as a set, the data of this set also are stored in memory cell 606;

Subband selected cell 603 is configured to the information according to judging unit 602, reading cells 606, will with bunch the energy rank of m subband of each sensing node compare, select the global energy rank of maximum sub belt energy rank, m=1...N as this m subband _Sub, N _SubBeing the sub band number of frequency band, is the natural number greater than 1, the subband selection course as described in Figure 3, the N as a result that subband is selected _SubThe global energy rank of individual subband also is stored in memory cell 606;

Computing unit 604 is configured to the information according to subband selected cell 603, and reading cells 606 is with N _SubThe global energy rank of individual subband averages, and draws the global energy rank E of this bunch _Global

Decision unit 605, be configured to computing unit draw bunch the energy measuring thresholding of global energy rank and this bunch compare judgement, draw the frequency spectrum judging of this bunch: if the global energy rank is greater than the energy measuring thresholding of this bunch, then judge on the frequency band of this bunch and have the main system signal, if less than the energy measuring thresholding of this bunch, then judging on the frequency band of this bunch, the global energy rank do not have the main system signal.

Memory cell 606 is configured to store various kinds of data.

According to an optional embodiment of the present invention, preferred, the described device that converges can be installed in the base station.

Fig. 7 provides the architecture of base station schematic diagram according to an embodiment of the invention.

In the embodiments of the present invention, base station 700 comprises frequency spectrum perception management devices 500 and frequency spectrum perception is converged device 600, carries out frequency spectrum perception management as described above and frequency spectrum perception and converges.Concrete structure repeats no more as shown in Figure 7 here.

Fig. 8 provides the frequency spectrum sensing device structural representation according to an embodiment of the invention.

In the embodiments of the present invention, frequency spectrum sensing device 800 is used for carrying out frequency spectrum perception according to the information that receives, and carries out spectrum energy and detects and the detection feedback result.Frequency spectrum sensing device 800 comprises receiving element 801, energy detection unit 802 and feedback unit 803.

Concrete, receiving element 801 is configured to the received spectrum perceptual parameters, comprises receiving element, is used for the received spectrum perceptual parameters, comprises sub band number N _SubAnd detecting period, N _SubFor greater than 1 natural number;

Energy detection unit 802 is configured to the information according to receiving element 801 inputs, carries out perceived spectral in the frequency spectrum perception time, carries out energy measuring, measures all N _SubIndividual subband is in the energy rank of frequency domain;

Feedback unit 803 is configured to all N that energy detection unit 802 is detected _SubIndividual subband feeds back to frequency spectrum perception in the energy rank of frequency domain and converges device.

Mandatory declaration be, in the above-described embodiment, the independent frequency spectrum perception of carrying out of each bunch, but the perception request is at all bunches in the sub-district, because in 802.22 systems, defined synchronous execution frequency spectrum perception, therefore generally require each bunch to carry out frequency spectrum perception simultaneously, can avoid the phase mutual interference like this, cause the perception mistake.But application of the present invention is not limited, and the perception request can be bunch to be that unit initiates, and the parameter of each bunch is separate, can be the same or different the frequency spectrum perception request separately of each bunch basis, the independent frequency spectrum perception of carrying out.

Utilize cooperation cognitive method of the present invention, more local perception information sends to fusion center, can help fusion center to make more accurate perception judges, and the ceiling capacity rank of each subband is selected between all cooperation sensing nodes, and the sub belt energy rank of simultaneously dark selectivity decline is not made contributions to the global energy rank.By this mode, can obtain multi-user diversity, reduce frequency selective fading, improve perceptual performance.

By the perceptual performance of the cooperation perception of multi-user diversity that utilizes of the present invention is carried out Computer Simulation, can intuitively obtain technical performance of the present invention.

In emulation, suppose that frequency selective fading channels has 6 independent pathways, the amplitude A k Rayleigh distributed of k paths, power delay profile is

The phase deviation of every paths [0,2 π) between evenly distribute.Separate between the Selective Fading Channel of different sensing nodes.At local sensing node, detecting period T _Sensing=1ms, false alarm rate is: PFA=10%.

Fig. 9 represents to survey according to omission of the present invention the performance simulation result schematic diagram of probability and sub band number.Wherein the average SNR of local sensing node is-12dB.From above-mentioned simulation result, can obtain along with sub band number and sensing node number increase, omission is surveyed probability and is reduced.The above-mentioned proof more cut apart subband and many more sensing nodes can bring a higher multi-user diversity gain more, but on the other hand, subband is many more, and the feedback information that feeds back to fusion center is many more, and this also causes the transmission quantity expense to increase.Therefore, spectra sharing system should reasonably be provided with number of sub-bands with the satisfaction need for understanding.

Figure 10 represents to survey probability and signal-to-noise performance simulation result schematic diagram according to omission of the present invention, proves bigger sub band number and more sensing node, can reduce omission and survey probability.As a comparison, Figure 10 also is given in existing cooperation perception algorithm performance under the situation of same channel conditions and perceptual parameters to show comparison.Can know and find out that the omission of the traditional algorithm during N=3 is surveyed probability even than N=2 and N of the present invention _SubIt is taller that probability is surveyed in omission under=1 the condition, the improvement in performance of 4dB.Proof the present invention can bring obvious multi-user diversity gain, effectively contrary frequency selectivity decline.

The present invention can realize with hardware, software, firmware and their combination.One skilled in the art would recognize that also in can be on the signal bearing medium that uses for any suitable data treatment system set computer program and embody the present invention.The sort signal bearing medium can be transmission medium or the recordable media that is used for machine sensible information, comprises magnetizing mediums, light medium or other suitable media.The example of recordable media comprises: disk in the hard disk drive or floppy disk, the CD that is used for CD-ROM drive, tape, and thinkable other media of those skilled in the art.One skilled in the art would recognize that any communication equipment with suitable programmed device all can carry out the step as the inventive method that embodies in the program product.

Should be appreciated that from foregoing description, under the situation that does not break away from spirit of the present invention, can make amendment and change each execution mode of the present invention.Description in this specification is only used for illustrative, and should not be considered to restrictive.Scope of the present invention only is subjected to the restriction of claims.

Claims (12)

1. the frequency spectrum sensing method of a spectra sharing system, described spectra sharing system comprises main system and from system, comprises the base station from system, fusion center and sensing node, described method comprises,

The perception request is initiated in the base station;

Sub-clustering is carried out to the sensing node in the sub-district in the base station, and the energy measuring thresholding that is provided with bunch is provided with the frequency spectrum perception parameter, and frequency band division is become a plurality of subbands;

Base station broadcast frequency spectrum perception parameter;

Sensing node is carried out energy measuring, measures the energy rank of all subbands at frequency domain, and the energy rank of all subbands is reported to fusion center;

Fusion center receives the energy rank report of sensing node, and the energy rank of all subbands of the sensing node report of same cluster is merged, the global energy rank that draws bunch;

Fusion center will bunch the energy measuring thresholding of global energy rank and this bunch compare the frequency spectrum judging that draws this bunch: if the global energy rank is greater than the energy measuring thresholding of this bunch, then judge on the frequency band of this bunch and have the main system signal, if less than the energy measuring thresholding of this bunch, then judging on the frequency band of this bunch, the global energy rank do not have the main system signal.

2. method according to claim 1, wherein, the frequency spectrum perception parameter includes but not limited to sub band number N _Sub, detecting period, N _SubFor greater than 1 natural number.

3. method according to claim 2, wherein, described fusion center merges the energy rank of all subbands of the sensing node of same cluster report, and the global energy rank that draws bunch is meant:

To compare with the sub belt energy rank of m subband of each sensing node of cluster, select the global energy rank of maximum sub belt energy rank, m=1...N as m subband _Sub

Fusion center is with N _SubThe global energy rank of individual subband averages, and draws the global energy rank of this bunch.

4. according to the described method of claim 1-3, wherein, described fusion center can be the base station, and described sensing node can be an end user device.

5. frequency spectrum perception management devices, be operated in spectra sharing system from system, the described base station that from system, comprises, sensing node, described device comprises:

Initiate the unit, be used to initiate the frequency spectrum perception request;

The unit is set, is used for the sensing node sub-clustering, the energy measuring thresholding that is provided with bunch further, is provided with the unit and also is used to be provided with the frequency spectrum perception parameter, and frequency band division is become a plurality of subbands;

Transmitting element is used for to sensing node broadcast spectrum perceptual parameters.

6. device according to claim 5, described frequency spectrum perception parameter includes but not limited to sub band number N _Sub, detecting period, N _SubFor greater than 1 natural number.

7. device according to claim 6, described device can be installed in the base station.

8. a frequency spectrum perception is converged device, and the described device that converges comprises

Receiving element is used to receive the energy rank report from all subbands of sensing node;

Judging unit, be used to judge sensing node bunch, will with bunch the energy rank of all subbands of sensing node be classified as a set;

The subband selected cell, be used for with bunch the energy rank of m subband of each sensing node compare, select the global energy rank of maximum sub belt energy rank, m=1...N as this m subband _Sub, N _SubBeing the sub band number of frequency band, is the natural number greater than 1;

Computing unit is used for N _SubThe global energy rank of individual subband averages, and draws the global energy rank of this bunch;

Decision unit, be used for will bunch the energy measuring thresholding of global energy rank and this bunch compare the frequency spectrum judging that draws this bunch: if the global energy rank is greater than the energy measuring thresholding of this bunch, then judge on the frequency band of this bunch and have the main system signal, if less than the energy measuring thresholding of this bunch, then judging on the frequency band of this bunch, the global energy rank do not have the main system signal.

9. the device that converges according to claim 7, the described device that converges can be installed in the base station.

10. base station, described base station comprises described device of claim 7 and the described device of claim 9.

11. a frequency spectrum sensing device comprises

Receiving element is used for the received spectrum perceptual parameters, comprises sub band number N _SubAnd detecting period, N _SubFor greater than 1 natural number;

Energy detection unit is used for perceived spectral, carries out energy measuring, measures the energy rank of all subbands at frequency domain;

Feedback unit is used to feed back the energy rank of all subbands.

12. frequency spectrum sensing device according to claim 11, described device is installed on the end user device.

Images