CN106162724A - A kind of D2D method for discovering equipment based on social networks - Google Patents

Abstract

The invention discloses a kind of D2D method for discovering equipment based on social networks.First, obtained the social information of user, such as user's frequency of exposure, Connection Time etc. by base station, thus draw the social central value of user；Then proposing a kind of D2D based on social networks and find method, according to the social central value of user, user is carried out the packet of social by base station；The component that last base station is different joins different energy budgets so that the user that central value is high is assigned to the discovery for equipment of the higher energy budget.Implement the present invention, can reasonably distribute energy, thus the equipment significantly improving D2D communication finds ratio, promote whole system performance, and the complexity that scheme is implemented is also within controlled range in the case of energy budget is limited.

Description

A kind of D2D method for discovering equipment based on social networks

Technical field

The present invention relates to wireless communication technology field, particularly relate to a kind of D2D method for discovering equipment based on social networks.

Background technology

For now, along with the explosive increase of mobile communication flow, increasing power system capacity, promoting spectrum efficiency becomes The problem that communication network is in the urgent need to address.D2D (Device-to-Device) communication is a kind of under the control of system, The new technique directly communicated between the subscriber equipment of multiple support D2D functions, it can efficiently reduce system resource Take, increase frequency spectrum efficiency of cellular communication system, reduce terminal sending power consumption, and save network operation to a great extent This.Compared with the technology such as WLAN, Wifi, bluetooth, D2D communication can communicate with the mandate frequency spectrum resource of multiplexing cellular network, Having higher reliability and security, the working method of D2D based on Cellular Networks is as shown in Figure 1.

One important technology and the premise of D2D communication are the mutual discovery procedures between D2D subscriber equipment, i.e. D2D equipment is sent out Existing process.At present, current equipment finds to be broadly divided into two kinds, and a kind of is the discovery of network assistance, i.e. the gateway detection of base station is sent out Existing potential D2D communication is right, and the second is that equipment passes through to send the communication parter that the autonomous discovery of discovery signal is potential, Hou Zheyou In it precisely, the feature such as quickly, be the emphasis of current research.But both discovery strategies are all based on mobile communication system, by Being the most mobile in user side, this finds a challenge beyond doubt to equipment accurately.

There is social networks exchange mass data in and the using of surrounding user always inevitable in view of mobile subscriber, because of This mobile subscriber can form a social networks having stable social characteristic by mobile devices such as smart mobile phones.Mobile use Family constitutes different social colonies by different hobbies and interest.In these social colonies, user generally has similar Content interested, such as would generally share identical content between friend.It is generally in the user of same community body, all has There is more stable social networks, be safe the most each other, directly set up communication than traditional D2D communication system The safety of link is much higher, and therefore we can consider the concept of social networks to introduce D2D communication.

Summary of the invention

In view of this, it is an object of the invention to provide a kind of method for discovering equipment based on social networks, it is possible to controlling Under scheme complexity, the effective equipment that improves finds ratio, improves data delivery rate and improves with reducing mean transit delay The performance of whole system.

The present invention is by the techniques below means above-mentioned technical problem of solution:

Step one: the communication information of D2D user used in minute book community, base station, when such as user's frequency of exposure, connection Between etc., thus draw the social central value of user；

Step 2: user, according to the social information of the user known, is grouped by base station according to social central value；

Step 3: after packet, carries out the selection of beacon detection mode, and final selection two-course beacon detection mode is carried out Equipment finds；

Step 4: base station, under limited energy budget, is different grouping according to the height of the social central value of difference group Distribution energy finds for equipment.

As optimization, the social central value of described user can be expressed as:

WhereinIt is the factor of influence of social colony c,Represent that node i is in social activity With other node mean exposure rates, N in colony c_cRepresent the number of users of social colony c,Be D2D to contact rate,It is that D2D is to contact time interval CI_ijCumulative distribution function.

As optimization, user is grouped according to the size of social central value, can be expressed as:

User is divided into the irrelevance of the social central value of user and social central value average in G group, reduction group as far as possible, its Middle pi is g_iThe average of group user social contact central value.

As optimization, described selection suitable beacon detection mode, use periodic two-course beacon detection mode, i.e. Source node and destination node the most periodically send beacon and detect.

As optimization, described under limited energy budget, reasonably join different beacon detections for different components Rate, including:

The user that social central value is higher plays the part of prior role the most in a network, with surrounding user contact number of times Wanting many, find in order to equipment so more multiple resource should be distributed to, namely many energy budgets increase its look-in frequency, thus Realizing the reasonable distribution of energy, concrete distribution standard joins different energy for different components exactly, and criterion is as follows:

ε is total energy budget, wherein

ξ_i=Ng_iμ_i

ξ_iRepresent i-th group with μ_iDetectivity power consumption when detecting.

Beneficial effects of the present invention: the present invention D2D method for discovering equipment pair based on social networks by a kind of novelty Equipment in the case of fixed energies budget finds that scheme carries out rational resource distribution, it is possible under control program complexity, The effective equipment that improves finds ratio, improves data delivery rate and improves the property of whole system with reducing mean transit delay Energy.

Accompanying drawing explanation

Fig. 1 is the system model figure of the present invention；

Fig. 2 is the schematic flow sheet of the present invention.

Detailed description of the invention

Below with reference to accompanying drawing, the present invention is described in detail:

As shown in Figure 1-2:

Cellular system has certain coverage, a total of N number of user, user here refer to mobile phone user or its The equipment that he moves, position is becoming always, all of mobile subscriber is usedRepresenting, any user can pass through Base station communicates, it is also possible under the power in base station controls, communicate with the user that closes in its transmission range.For appointing Two mobile subscribers of meaningWhen in the transmission range that they move to each other, they can carry out D2D communication.Base In the system shown in Fig. 1, the invention discloses a kind of D2D method for discovering equipment based on social networks, as in figure 2 it is shown, based on The D2D method for discovering equipment of social networks may comprise steps of:

Step one: the communication information of D2D user used in minute book community, base station, when such as user's frequency of exposure, connection Between etc., thus draw the social central value of user；

Specific as follows:

1) relevant informations such as interval time of contact of any D2D user couple, contact rate, time of contact are known in base station:

When node i and node j move to each other outside transmission range, both arrive again at required in transmission range each other Time is that the time of contact of user is spaced by D2D, can be expressed as

D2D is to contact time interval, L_i(t)、L_iT () represents the position of node i, j respectively,Represent node i, the biography of j Defeated scope.

If node i, j are at time t_cIn the range of arrival communicates with one another, thenWith Represent t_cBefore.Time of contact is the time that node i, j leave before transmission range each other, for

CI_i,j=t-t_c (3)

CT_i,jBeing steady stochastic variable, its cumulative distribution function is F_CTi,j(x)。

Based on user's frequency of exposure within the persistent period in past, the contact rate of user is converted into contact by balance ground Figure, then divides social colony with colony algorithm K-CLIQUE, represents all of social colony, social colony with C after division Division be based on contact rate and the central value of user, so different social colony is different on the impact of whole network, use Social influence factor f represents the impact of colony, is f for the most social its factor of influence of colony c_c, represent in this social group The frequent degree of user's communication with one another in body, is that the mean exposure rate by all users obtains:

WhereinRepresent node i in societies c with other node mean exposure rates, N_cRepresent The number of users of colony c,It is that D2D is to contact rate.

The social central value of base station calculating:

WhereinIt is that D2D is to contact time interval CI_ijCumulative distribution function.、

Step 2: user, according to the social information of the user known, is grouped by base station according to social central value；

It is divided into G group according to following principle:

Wherein pi is the meansigma methods of gi group user social contact central value, and the meaning is just to try to the social center of user in reduction group Value and the irrelevance of central value average.

Step 3: after carrying out playing the packet of social, need user to send beacon to detect neighbor user the most exactly, Need to carry out the selection of detection mode.Specific as follows: detection mode has two kinds, unidirectional detection and bi-directional probing.Unidirectional detection is just It is that purpose joint transmission beacon detects, if destination node is not detected by the beacon of source node, is considered as the detection of this beacon Failure, in order to reduce the false dismissal probability of device discovery procedure, this use novel employing two-course beacon detects, it is simply that dock at D2D In tactile time interval, purpose source node and destination node send beacon simultaneously and detect.To sum up, adhoc formula two-course beacon is used Detection mode, i.e. source node and destination node periodically send beacon and carry out detection each other.

Step 4: the decision-making of beacon detectivity, it is simply that under limited energy budget, reasonably joins not for different components Same beacon detectivity, specific as follows: the user that social central value is higher plays prior role the most in a network, with The contact of surrounding user is more frequent, for avoiding blocking up, it should distribute more resource in order to set to the user that central value is higher Preparation is existing, and namely more energy budget, increases the frequency of its detection.

Assume that i-th group is with μ_iLook-in frequency when detecting, then i-th group number can be:

ξ_i=Ng_iμ_i (8)

Concrete distribution standard joins different energy for different components exactly, and criterion is as follows:

I.e. we are the sizes of interior customer center value according to group, pro rata distribute energy budget, difference with traditional not Considering that user's centrad in a network unifies the pattern of beacon look-in frequency, we achieve the distribution that energy is relatively reasonable.

Above example is only in order to illustrate technical scheme and unrestricted, although with reference to preferred embodiment to this Invention has been described in detail, and it will be understood by those within the art that, can repair technical scheme Changing or equivalent, without deviating from objective and the scope of technical solution of the present invention, its right that all should contain in the present invention is wanted Ask in the middle of scope.

Claims (6)

1. a D2D method for discovering equipment based on social networks, for mobile communication terminal, it is characterised in that include Step:

Step one: the communication information of D2D user used in minute book community, base station, such as user's frequency of exposure, Connection Time etc., Thus draw the social central value of user；

Step 2: user, according to the social information of the user known, is grouped by base station according to social central value；

Step 3: after packet, carries out the selection of beacon detection mode, and final selection two-course beacon detection mode carries out equipment Find；

Step 4: base station, under limited energy budget, is different grouping distribution according to the height of the social central value of difference group Energy finds for equipment.

A kind of D2D method for discovering equipment based on social networks the most according to claim 1, the meter of described social central value Calculation formula is as follows:

WhereinIt is the factor of influence of social colony c,Represent that node i is in social colony With other node mean exposure rates, N in c_cRepresent the number of users of social colony c,It is that D2D is to contact time interval CI_ij Cumulative distribution function.

A kind of D2D method for discovering equipment based on social networks the most according to claim 1, it is characterised in that by user Being divided into G group according to social central value, the principle of packet is:

$min\underset{i=1}{\overset{G}{\Σ}}\underset{S_j\∈g_i}{\Σ}\left|\right|S_j-pi|{|}^2$

Wherein pi is the average of gi group user social contact central value.

A kind of D2D method for discovering equipment based on social networks the most according to claim 1, it is characterised in that described double It is that source node and destination node the most periodically send beacon and detect to beacon detection mode.

A kind of D2D method for discovering equipment based on social networks the most according to claim 1, it is characterised in that limited Energy budget under, reasonably join different beacon detectivitys for different components, user's component that central value is high joins many energy Amount budget, the highest beacon detection rate, it is assigned to high energy budget.

A kind of D2D method for discovering equipment based on social networks the most according to claim 5, it is characterised in that distribution standard As follows:

$\begin{array}{c}{\mathrm{\ξ}}_G:{\mathrm{\ξ}}_{G-1}:...{\mathrm{\ξ}}_2:{\mathrm{\ξ}}_1=G:(G-1):...2:1\\ \begin{array}{cc}s.t.& \underset{i=1}{\overset{G}{\mathrm{\Σ}}}{\mathrm{\ξ}}_i=\mathrm{\ϵ}\end{array}\end{array}$

ε is total energy budget, wherein

ξ_i=Ng_iμ_i

ξ_iRepresent i-th group with μ_iDetectivity power consumption when detecting.