CN103596120B - D2D communication method in macro cell and small cell heterogeneous network - Google Patents

Abstract

The invention discloses a D2D communication method in a macro cell and small cell heterogeneous network. The D2D communication method puts forward five D2D communication modes which are composed of a dedication mode, a macro cell mode, a reused macro cell channel mode, a small cell mode and a reused small cell mode. A D2D user selects the D2D communication modes of highest system energy efficiency for communication. According to the D2D communication method, the small cell mode and the reused small cell mode are added into an existing D2D communication method, the quantity of the modes which can be selected by the D2D user is increased, and the freedom degree of selecting the D2D modes is enhanced. In addition, the working characteristics of the D2D communication method in the macro cell and small cell heterogeneous network are fully utilized, so that the use rate of a frequency spectrum is enhanced. Besides, due to the fact that the D2D user selects the D2D communication modes of the highest system energy efficiency for the communication, frequency spectrum efficiency and energy loss of D2D communication are comprehensively considered, and energy loss is reduced as much as possible while the frequency spectrum efficiency is enhanced.

Description

D2d communication means in macrocellular and cellulor heterogeneous network

Technical field

The present invention relates to the communications field, particularly to the d2d communication means in a kind of macrocellular and cellulor heterogeneous network.

Background technology

With the fast development of wireless communication system, existing single network system cannot meet two-forty, big letter Road capacity, the communicating requirement of high quality-of-service, the side that next generation wireless communication technology is just merging towards plurality of wireless networks isomery To development.Heterogeneous network refers to, in the range of macro base station covers, introduce other communication modes, targetedly strengthens given zone The covering in domain, forms a kind of network structure that multilamellar covers, and has network networking flexibly, maintenance cost is cheap, thus receives Widely pay close attention to.Introducing cellulor in single macrocellular network is to use relatively broad heterogeneous network, cellulor at present It is distributed in macrocellular, each cellulor has independent little base station (small cell base station, sbs).Cellulor Refer to that coverage covers less cellular network relative to macrocellular.The little base station of each cellulor can be by cellular network operator Or consumer disposes.Macrocellular load capacity can effectively be mitigated by introducing cellulor, improve user communication quality.

Terminal direct connection (device-to-device, d2d) communication is a kind of logical under the control of system it is allowed between terminal Cross the new technique that multiplexing honeycomb channel carries out direct-connected communication, it can increase the spectrum utilization efficiency of cellular system, mitigate honeybee The load of nest cell base station, reduction terminal transmission power, lift system entire throughput, solve radio communication to a certain extent The deficient problem of system spectral resources.

D2d communication pattern is a very important problem in d2d communication, by selecting suitable communication pattern, honeycomb The spectrum efficiency of network can be greatly improved.In single network, (i.e. d2d communicating pair, sends out d2d user including d2d Penetrate end and d2d receiving terminal) can be communicated using Three models:

(1) macrocellular pattern: as traditional cellular communication modes, d2d user is realized as relaying using macro base station Between information transfer, and using not by same cell other phone users use macrocellular channel, this channel is in d2d user When not communicating, can be used by macrocell user；

(2) dedicated mode: two users' direction communication, it is not necessary to be relayed by base station, is distributed exclusively for it using macrocellular Dedicated channel, the macrocellular channel that this dedicated channel is not used by other macrocell user, and can only being used by d2d user, This channel idle when d2d user does not communicate, can not be used by macrocell user；

(3) it is multiplexed macrocellular channelling mode: two users' direction communication.Different from dedicated channel pattern, multipling channel pattern Under, d2d user is used in conjunction with identical channel with the phone user that is re-used.

In macrocellular and cellulor heterogeneous network, the channel resource of honeycomb and single network are very different, cellulor Part macrocellular channel resource can be taken or using new channel resource.Therefore, under heterogeneous network, d2d model selection meeting Can be very different with the model selection under single macrocellular network, and due to introducing one in macrocellular and cellulor heterogeneous network The cellulor of fixed number amount, carries out channel multiplexing and improves the availability of frequency spectrum, but due to channel multiplexing, makes the interference of communication system Strengthen, and then lead to the energy consumption of whole heterogeneous network to increase, it can be considered that improving the availability of frequency spectrum and reducing energy consumption presence Certain contradiction.Reducing energy consumption as far as possible while improving the availability of frequency spectrum, solves contradiction therebetween, is macrocellular With the d2d communication major issue to be solved in cellulor heterogeneous network.And existing document does not consider macrocellular and little The d2d mode selection problem of the d2d communication in honeycomb heterogeneous network, does not consider to improve the availability of frequency spectrum and reducing energy consumption simultaneously Problem.

Content of the invention

The deficiency that the d2d communication that the present invention is directed in existing macrocellular and cellulor heterogeneous network exists, there is provided one Plant the d2d communication means in macrocellular and cellulor heterogeneous network, the method can effectively improve the availability of frequency spectrum and reduce energy Consumption problem.

A kind of d2d communication means in macrocellular and cellulor heterogeneous network, described macrocellular and cellulor heterogeneous network Network has 5 kinds of alternative d2d communication patterns, respectively dedicated mode, macrocellular pattern, multiplexing macrocellular channelling mode, Cellulor pattern and multiplexing cellulor channelling mode,

Under cellulor pattern, d2d user is communicated with little base station for relaying, and using the minimum cellulor letter of interference Road,

Under multiplexing cellulor channelling mode, d2d user's direction communication, and it is multiplexed little to d2d receiving terminal interference minimum The channel of phone user；

Described d2d communication means includes:

(1) calculate the system energy efficiency of the d2d communication system under 5 kinds of d2d communication patterns respectively,

(2) relatively and determine system energy efficiency highest d2d communication pattern,

(3) d2d user is communicated using the d2d communication pattern that step (2) determines；

Described d2d communication system includes d2d user, the macrocell user that is re-used, be re-used cellulor user and being done Disturb cellulor user；

Described system energy efficiency is the overall channel capacity of all users and total bandwidth and total transmitting in d2d communication system The long-pending ratio of power.

The macrocell user that is re-used is defined as d2d using the grand honeybee with d2d users to share channel during multiplexing macrocellular pattern Nest user, the cellulor user that is re-used is defined as d2d using the cellulor with d2d users to share channel during multiplexing cellulor pattern User, disturbed cellulor user is defined as d2d and adopts the cellulor user with d2d users to share channel during cellulor pattern. The present invention, under any pattern, be re-used macrocell user, and be re-used cellulor user and disturbed cellulor are with depositing per family It is being considered d2d communication system.

The d2d communication means of the present invention with respect to the d2d communication means of existing single Cellular Networks, except existing 3 kinds D2d communication pattern (including dedicated mode, macrocellular pattern and multiplexing macrocellular channelling mode) outward, additionally provides cellulor pattern With multiplexing cellulor channelling mode, take full advantage of macrocellular and the feature of cellulor heterogeneous network, improve the availability of frequency spectrum. And invention also defines system energy efficiency, d2d user is led to using system energy efficiency highest d2d communication pattern Letter, considers the availability of frequency spectrum and the energy loss of d2d communication, during system energy efficiency highest, the availability of frequency spectrum and energy Loss all reaches optimum, so that the two is mutually balanced, efficiently solves contradiction therebetween.

The system energy efficiency of described macrocellular pattern and cellulor pattern can determine according to d2d user present position:

If d2d user is in the coverage of cellulor, the system energy efficiency making macrocellular pattern is 0；

Otherwise, the system energy efficiency making cellulor pattern is 0.

Wherein, judge whether d2d user is in the covering model of same cellulor according to the signal intensity that d2d user receives Enclose:

If the signal intensity of the macro base station that d2d user receives is less than the signal intensity from same little base station, judge D2d user is in same cellulor coverage；

Otherwise, it is determined that d2d user is in outside cellulor coverage.

D2d user is in same cellulor coverage, then carrying out communication using cellulor pattern must be than using grand System energy efficiency when honeycomb mode is communicated is low, conversely, carrying out communication using macrocellular pattern must adopt chalcid fly by ratio System energy efficiency when snap formula is communicated is low.Because d2d user selects the maximum d2d communication mould of system energy efficiency Whether formula, then be in same cellulor coverage according to d2d user and directly determine macrocellular pattern or cellulor pattern System energy efficiency is 0, can effectively reduce operand, improves traffic rate.

Described system energy efficiency is according to formula:

$\mathrm{\η}=\frac{c_1+c_2+c_3+c_4}{p\×w}$

Calculate, wherein:

c₁Represent the channel capacity of d2d user,

c₂Represent the channel capacity of the macrocell user that is re-used,

c₃Represent the overall channel capacity of all cellulor users that are re-used,

c₄Represent the overall channel capacity of all disturbed cellulor users,

P is the transmission power sum of all users in d2d communication system,

W is the channel width sum of all users in d2d communication system.

Channel capacity refers to the maximum rate that channel is provided that, channel capacity is public according to Shannon (shannon) channel capacity Formula:

$c={\mathrm{wlog}}_2(1+\frac{s}{i+n})$

Calculate, wherein s, i, n are expressed as the signal intensity receiving, interference and the noise power of receiving terminal, and w represents For channel width, the s during channel capacity of calculating different user, the value of i with n is different.D2d transmitting terminal under 5 kinds of d2d communication patterns Transmission power:

(a) dedicated mode:

(b) macrocellular pattern:

(c) multiplexing macrocellular channelling mode:

(d) cellulor pattern:

(e) multiplexing cellulor channelling mode:

Wherein, p_dRepresent the transmission power of d2d transmitting terminal, γ_dthFor the Signal to Interference plus Noise Ratio thresholding of d2d communication link, n₀For making an uproar Power sound spectrum density, h_abFor the channel gain between d2d communicating pair, h_abIncrease for the channel between d2d transmitting terminal and macro base station Benefit,For d2d transmitting terminal and the channel gain between little base station, i belonging to it_mrFor the macrocell user that is re-used to d2d receiving terminal Interference,For the interference to base station little belonging to d2d user for the disturbed cellulor user, i_srUse for all cellulors that are re-used The interference to d2d receiving terminal for the family, w_dChannel width for d2d transmitting terminal.Due to during using cellulor pattern, d2d communicating pair (including transmitting terminal and receiving terminal) must be in same cellulor coverage, and now little base station belonging to d2d user is exactly that d2d connects Little base station belonging to receiving end.

Under different d2d communication patterns, the channel source of d2d user is as follows:

Under dedicated mode, the macrocellular channel that macro base station is not arbitrarily used by other macrocell user for d2d user's distribution, When d2d user does not adopt dedicated mode communication, this channel keeps idle condition, is not used by macrocell user, therefore this letter Road is considered as dedicated channel.Under this pattern: w_d=w_de, w_deBandwidth for dedicated channel；

Under multiplexing macrocellular channelling mode, the interference on macrocellular channel that the perception of d2d receiving terminal has been used, select dry The macrocellular channel disturbing minimum is multiplexed, under this pattern: w_d=w_mr, w_mrBandwidth for the channel that is re-used；

Under macrocellular channelling mode, the free time grand honeybee that macro base station is not arbitrarily used by this cell other users for d2d distribution Nest channel, and when d2d user does not adopt dedicated mode communication, this channel can be used by macrocell user, under this pattern: w_d =w_m, w_mDistribute to the channel width of d2d transmitting terminal for macrocellular；

Under cellulor channelling mode, belonging to d2d user, little base station perceives the interference on cellulor channel, is d2d transmitting terminal The minimum cellulor channel of distribution interference, this channel may also be used under this pattern by cellulor user the free time: w_d=w_s, w_sBandwidth for disturbed cellulor user；

During multiplexing cellulor channelling mode, the interference on cellulor channel that the perception of d2d receiving terminal has been used, select dry The cellulor channel disturbing minimum is multiplexed, and this channel is used by cellulor user, under this pattern: w_d=w_sr, w_srBe by The channel width note of multiplexing cellulor user.

D2d transmission power p_dSignal to Interference plus Noise Ratio threshold requirement according to receiving terminal determines, the d2d under any pattern receives termination The Signal to Interference plus Noise Ratio receiving is equal to a certain thresholding γ_dthIt may be assumed that

$sinr=\frac{p_d{h}_{ab}}{i+n_0}={\mathrm{\γ}}_{dth}$

Channel capacity c of d2d user₁According to shannon formula:

c₁=w_dlog₂(1+γ_dth)

Calculate.

Be re-used channel capacity c of macrocell user₂According to:

$c_2=w_{mr}{\log }_2(1+\frac{s_m}{i_{ab}+n_0{w}_{mr}})$

Calculate, wherein:

w_mrFor the channel width of the macrocell user that is re-used,

n₀For noise power spectral density,

s_mThe signal intensity from the macrocell user that is re-used receiving for macro base station,

i_abFor under the interference strength to macro base station for the d2d transmitting terminal, and multiplexing macrocellular channelling mode:

i_ab=p_dh_ab,

Under other patterns, d2d is not multiplexed macrocell user channel, therefore d2d user cellular system is not caused any Interference, meanwhile, d2d does not receive the interference that macrocell user brings yet, therefore, under remaining d2d communication pattern: i_ab=0.

Overall channel capacity c of all cellulor users that are re-used₃According to formula:

$c_3=\underset{n=1}{\overset{n}{\σ}}{c}_s^n=\underset{n=1}{\overset{n}{\σ}}{w}_{sr}{\log }_2(1+\frac{s_n}{i_{as}^n+i_n+n_0{w}_{sr}})$

Calculate, wherein:

w_srFor the channel width of the cellulor user that is re-used,

N is to be re-used the number of cellulor user,

For the channel capacity of the cellulor user n that is re-used,

i_nCome from the cellulor user's that other are re-used for what the little base station belonging to cellulor user n that is re-used received Interference strength,

For d2d transmitting terminal and the channel gain between little base station belonging to cellulor user n that is re-used,

s_nThe signal from the cellulor user n that is re-used receiving for the little base station belonging to cellulor user n being re-used Intensity,

For the interference strength to the little base station belonging to cellulor user n that is re-used for the d2d transmitting terminal, and it is multiplexed cellulor channel During pattern:Under remaining pattern

The present invention considers that the cellulor user in different cellulors may adopt same cellulor channel, and the therefore present invention examines Consider the total n cellulor user being in different cellulors using the same cellulor channel that is re-used, that is, have n cellulor to use Family can be disturbed by d2d user.Under other patterns, d2d is not multiplexed these cellulor channels, therefore these cellulors user not Be subject to from d2d user multiplexing bring disturb, therefore

Overall channel capacity c of all disturbed cellulor users₄According to formula:

$c_4=\underset{r=1}{\overset{r}{\σ}}{c}_s^r=\underset{r=1}{\overset{r}{\σ}}{w}_s{\log }_2(1+\frac{s_r}{i_{as}^r+i_r+n_0{w}_s})$

Calculate, wherein:

R is the number of disturbed cellulor user,

For the channel capacity of disturbed cellulor user r,

i_rWhat little base station belonging to disturbed cellulor user r received comes from the dry of other disturbed cellulor users Disturb,

For d2d transmitting terminal and the channel gain between little base station belonging to disturbed cellulor user r,

s_rThe signal from disturbed cellulor user r that little base station belonging to disturbed cellulor user r receives is strong Degree,

For the interference strength to the little base station belonging to cellulor user r that is re-used for the d2d transmitting terminal, and it is multiplexed cellulor letter Under road pattern:

$i_{as}^r=p_d{h}_{as}^r,$

Under remaining d2d communication pattern:

With described previously, the present invention considers that the cellulor user in different cellulors may adopt same cellulor channel, Therefore the present invention considers that the total r cellulor user being in different districts adopts same cellulor channel, that is, have r cellulor User can be disturbed by d2d user.Under other patterns, d2d does not use these cellulor channels, therefore these cellulors user It is not subject to from disturbing that d2d brings, therefore

In described d2d communication system, the channel width sum of all users is:

Under dedicated mode: w=w_de+w_mr+w_sr+w_s,

Under macrocellular pattern: w=2w_m+w_mr+w_sr+w_s,

Under other d2d communication patterns: w=w_mr+w_sr+w_s.

Wherein, w_deDistribute to the bandwidth of the dedicated channel of d2d user, w for macrocellular_mDistribute to d2d for little macrocellular to send out Penetrate the channel width at end.When calculating channel width sum, the bandwidth not double counting of identical channel.In dedicated mode and grand honeybee Under snap formula, system needs in addition to distribute channel for d2d user, and under other patterns, system does not need in addition to divide for d2d transfer Allocating channel.Under macrocellular pattern, because d2d communication process is with little base station for relaying, therefore now d2d receiving terminal is also required to letter Road, its channel width is also w_m, so the now a width of 2w of the band of d2d user_m.

D2d communication means in the macrocellular of the present invention and cellulor heterogeneous network is with respect to existing single Cellular Networks D2d communication means is it is proposed that 5 kinds of d2d communication patterns: include dedicated mode, macrocellular pattern and multiplexing macrocellular channelling mode, Cellulor pattern and multiplexing cellulor channelling mode, enrich the pattern quantity that d2d user can select, increased d2d pattern The degree of freedom selecting, the cellulor pattern of introducing and multiplexing cellulor channelling mode take full advantage of macrocellular and cellulor isomery The feature of network, improves the availability of frequency spectrum.And defining system energy efficiency, d2d user adopts system energy efficiency highest D2d communication pattern communicated, consider d2d communication the availability of frequency spectrum and energy loss, improve the availability of frequency spectrum While reducing energy consumption as far as possible.

Brief description

Fig. 1 is the schematic diagram of 5 kinds of d2d communication patterns of the present invention；

Fig. 2 is the flow chart of the d2d communication means in the macrocellular and cellulor heterogeneous network of the present invention；

Fig. 3 is the calculation process of the system energy efficiency of d2d communication system under 5 kinds of d2d communication patterns；

Fig. 4 is the functional relationship that in the present embodiment, average system energy efficiency tires out with the distance between d2d communicating pair.

Specific embodiment

Below in conjunction with the drawings and specific embodiments, the present invention will be further described.

In the present embodiment:

Definition is with the user that frequency user is using same channel；

Definition be re-used macrocell user be d2d using multiplexing macrocellular channelling mode when with d2d share same channel Macrocell user；

Definition be re-used cellulor user be d2d using multiplexing cellulor channelling mode when with d2d share same channel Cellulor user；

Defining disturbed cellulor user is that d2d shares same channel using during cellulor channelling mode with d2d transmitting terminal Cellulor user；

Defining d2d user is the communicating pair needing to carry out direct-connected communication, including transmitting terminal a and receiving terminal b；

Definition system energy efficiency is the system that d2d user, disturbed macrocellular and the cellulor user that is re-used form The total transmission power of the overall channel capacity of (i.e. d2d communication system) and all users in this system and the long-pending ratio of shared bandwidth Value, unit is bps/mw/hz；

Definition signal intensity and the interference strength useful signal respectively receiving and the power disturbing.

The application scenarios of the d2d communication means in the present embodiment macrocellular and cellulor heterogeneous network are as follows:

Macrocellular covering radius r_mb=1000m, cellulor covering radius is r_sbBetween=100m, d2d user, distance is 50 ～250m；Be deployed with 6 macrocell user in one macrocellular, the nonoverlapping cellulor of 2 coverages have same can Distribution channel resource, each cellulor respectively has 2 cellulor users, the quantity of the cellulor that is re-used；Use in same cellulor Family uses different channels, there is not interference between the user in same cellulor, the user in different cellulors can make Use identical channel, and there is interference using between the different cellulor users of same channel, there is the free time being not used by little Honeycomb channel, that is, d2d user using cellulor pattern when do not disturb other cellulors user, therefore r=0；1 couple of d2d user needs Model selection to be carried out；D2d user sinr thresholding γ_dthIt is 15db, all users (include transmitting terminal a, receiving terminal b, grand honeybee Nest user and cellulor user) bandwidth is 1mhz；Noise power spectral density n₀For -174dbm/hz；The road of cellular communication link Footpath is lost as 128.1+37.6log10 (d), and unit is db, and wherein d represents the distance between communicating pair, and unit is km, shade The average of decline is 0, variance is 10db.

In d2d communication means in the macrocellular of the present embodiment and cellulor heterogeneous network, d2d user can be available for selecting at 5 kinds One kind is selected to carry out d2d communication in the d2d communication pattern selected.The mould as shown in figure 1, respectively 5 kinds alternative d2d communicate Formula: macrocellular pattern, cellulor pattern, multiplexing macrocellular channelling mode, multiplexing cellulor channelling mode and the showing of dedicated mode It is intended to, specific as follows:

Macrocellular pattern: as traditional cellular communication modes, to be realized between d2d user using macro base station as continuing Information transfer, and using the macrocellular channel not used by other phone users in same cell, this channel does not communicate in d2d user When, can be used by macrocell user；

Dedicated mode: two users' direction communication it is not necessary to be relayed by base station, using not used by other honeycombs in same cell The macrocellular channel that family uses, and this channel can only use by d2d user, this channel idle when d2d user does not communicate, can not Used by macrocell user；

Multiplexing macrocellular channelling mode: two users' direction communication.Different from dedicated channel pattern, under multipling channel pattern, D2d user is used in conjunction with identical channel with the phone user that is re-used；

Cellulor pattern: d2d user is communicated with little base station for relaying, and using the sky not used by cellulor user Idle channel；

Multiplexing cellulor channelling mode: d2d user's direction communication, and it is multiplexed the cellulor minimum to the interference of d2d receiving terminal The channel of user.

The workflow of the d2d communication means in the macrocellular of the present embodiment and cellulor heterogeneous network as indicated with 2, including Following steps:

(1) calculate the system energy efficiency of the d2d communication system under 5 kinds of d2d communication patterns respectively；

(2) relatively and determine system energy efficiency highest d2d communication pattern；

(3) d2d user is communicated using the d2d communication pattern that step (2) determines.

Calculate the system energy efficiency of the d2d communication system under 5 kinds of d2d communication patterns according to following methods in step (1), As shown in Figure 3, comprising:

S101, respectively obtain d2d communicating pair (i.e. d2d user: transmitting terminal a and receiving terminal b) receive from grand base Stand signal intensity and from all little base stations maximum signal,

S102, according to step s101 obtain signal intensity size judge whether d2d communicating pair is in same cellulor In coverage:

If the signal intensity from macro base station that transmitting terminal a and receiving terminal b receives is less than the letter from same little base station Number intensity, then judge that transmitting terminal a and receiving terminal b is in same cellulor coverage, makes the d2d under macrocellular pattern communicate The system energy efficiency of system is 0；

Otherwise, it is determined that transmitting terminal a and receiving terminal b is in outside cellulor coverage, the d2d under cellulor pattern is made to communicate The system energy efficiency of system is 0.

In the present embodiment, result of determination is: transmitting terminal a and receiving terminal b is in same cellulor coverage, corresponds to Little base station n₀, then the system energy efficiency of the d2d communication system under macrocellular pattern is 0.

Parameter needed for s103, acquisition computing system energy efficiency

A () obtains d2d communicating pair, i.e. channel gain h between transmitting terminal a and receiving terminal b_ab, transmitting terminal a is to macro base station Between channel gain h_ab, and transmitting terminal a and little base station n belonging to it₀Between channel gain

B () determines be re-used macrocell user and relevant parameter

The interference from all macrocell user being perceived according to d2d receiving terminal, selects the minimum honeycomb of multiplexing interference Subscriber channel, carries a width of w_mr, this jamming power intensity is designated as i_mr；

C () determines be re-used cellulor user and relevant parameter

(c1) dry from cellulor user on the cellulor channel that receiving terminal b perception has been used by cellulor user Disturb, the channel selecting interference minimum is multiplexed, and the interference on this channel is designated as i_sr,

(c2) the channel cellulor user minimum using interference is defined as the cellulor user that is re-used, and obtains:

Transmitting terminal a and each channel gain between little base station belonging to cellulor user that is re-used, are designated asWherein n table Show the cellulor Customs Assigned Number that is re-used, n=1 ... n, n represent the cellulor total number of users that is re-used, n=2 in this enforcement,

And the interference that receives on selected channel of each little base station belonging to cellulor user that is re-used and signal intensity, It is designated as i respectively_n, s_n, n=1 ... n；

D () determines disturbed user and relevant parameter

Little base station n according to belonging to d2d receiving terminal₀The interference of the cellulor user from other little base stations perceiving, choosing Select the minimum cellulor user channel allocations of interference to d2d transmitting terminal, carry a width of w_s, this least interference power level is designated as Cellulor user using this channel is disturbed cellulor user.

S104, the transmitting work(of d2d transmitting terminal under 5 kinds of d2d communication patterns is calculated respectively according to the parameter that step s103 obtains Rate:

(a) dedicated mode:

(b) macrocellular pattern:

(c) multiplexing macrocellular channelling mode:

(d) cellulor pattern:

(e) multiplexing cellulor channelling mode:

S105, according to formula:

$\mathrm{\η}=\frac{c_1+c_2+c_3+c_4}{p\×w}$

Calculate, wherein:

c₁Represent the channel capacity of d2d user, according to formula:

c₁=w_dlog₂(1+γ_dth)

It is calculated,

c₂Represent the channel capacity of the macrocell user that is re-used, according to formula:

$c_2=w_{mr}{\log }_2(1+\frac{s_m}{i_{ab}+n_0{w}_{mr}})$

Calculate, wherein, i_abFor under the interference strength to macro base station for the d2d transmitting terminal, and multiplexing macrocellular channelling mode: i_ab =p_dh_ab, under remaining pattern: i_ab=0；

c₃Represent the overall channel capacity of all cellulor users that are re-used, according to formula:

$c_3=\underset{n=1}{\overset{n}{\σ}}{c}_s^n=\underset{n=1}{\overset{n}{\σ}}{w}_{sr}{\log }_2(1+\frac{s_n}{i_{as}^n+i_n+n_0{w}_{sr}})$

Calculate,For the interference strength to the little base station belonging to cellulor user n that is re-used for the d2d transmitting terminal, and it is multiplexed chalcid fly During nest channelling mode:Under remaining pattern

c₄Represent the overall channel capacity of all disturbed cellulor users, according to formula:

$c_4=\underset{r=1}{\overset{r}{\σ}}{c}_s^r=\underset{r=1}{\overset{r}{\σ}}{w}_s{\log }_2(1+\frac{s_r}{i_{as}^r+i_r+n_0{w}_s})$

Calculate, wherein:

For the interference strength to the little base station belonging to cellulor user r that is re-used for the d2d transmitting terminal, and it is multiplexed cellulor channel During pattern:Under remaining patternR is the number of disturbed cellulor user, r=0 in the present embodiment；

P is be re-used macrocell user, the cellulor user that is re-used, disturbed cellulor user and d2d user Transmission power sum, the power of the macrocell user that is wherein re-used is by macrocellular acquisition, the cellulor user that is re-used, disturbed The power of cellulor user is fed back from above-mentioned user's own base station to macro base station；

W is the channel width sum of all users in d2d communication system, is expressed as under different d2d communication patterns:

Under dedicated mode: w=w_de+w_mr+w_sr+w_s,

Under macrocellular pattern: w=2w_m+w_mr+w_sr+w_s,

Under other d2d communication patterns: w=w_mr+w_sr+w_s,

Wherein, w_deDistribute to the bandwidth of the dedicated channel of d2d transmitting terminal, w for macrocellular_mDistribute to d2d for little macrocellular The channel width of user.

In the present embodiment: w_de=1mhz, w_mr=1mhz, w_sr=1mhz, w_s=1mhz, w_m=1mhz.

Average system energy efficiency is expressed as the meansigma methodss of every 10000 analogue system energy efficiency samples.Due to chalcid fly Snap formula requires d2d communicating pair to be in same cellulor coverage, and the communication of not all d2d can be using single little Honeycomb mode, therefore single cellulor pattern does not possess comparability.Fig. 4 is that in 10000 emulation, all of d2d user adopts Different single-mode (respectively macrocellular pattern, multiplexing macrocellular channelling mode, cellulor pattern and multiplexing cellulor channel moulds Formula) function of distance between average system energy efficiency under communication and the communication of institute of the present invention extracting method and d2d communicating pair Relation.As can be seen that the mode selecting method being provided compares single-mode can provide bigger energy efficiency.

The above, the only specific embodiment of the present invention, but protection scope of the present invention is not limited thereto, and any Those familiar with the art the invention discloses technical scope in, the change or replacement that can readily occur in, all answer It is included within the scope of the present invention.

Claims (10)

1. the d2d communication means in a kind of macrocellular and cellulor heterogeneous network is it is characterised in that described macrocellular and chalcid fly Nest heterogeneous network has 5 kinds of alternative d2d communication patterns, respectively dedicated mode, macrocellular pattern, multiplexing macrocellular letter Road pattern, cellulor pattern and multiplexing cellulor channelling mode,

Under cellulor pattern, d2d user is communicated with little base station for relaying, and using the minimum cellulor channel of interference,

Under multiplexing cellulor channelling mode, d2d user's direction communication, and it is multiplexed the cellulor minimum to the interference of d2d receiving terminal The channel of user；

Described d2d communication means includes:

(1) calculate the system energy efficiency of the d2d communication system under 5 kinds of d2d communication patterns respectively,

(2) relatively and determine system energy efficiency highest d2d communication pattern,

(3) d2d user is communicated using the d2d communication pattern that step (2) determines；

Described d2d communication system includes d2d user, the macrocell user that is re-used, be re-used cellulor user and disturbed little Phone user；

Described system energy efficiency is the overall channel capacity of all users and total bandwidth and total transmission power in d2d communication system Long-pending ratio.

2. the d2d communication means in macrocellular as claimed in claim 1 and cellulor heterogeneous network is it is characterised in that described Macrocellular pattern and cellulor pattern system energy efficiency according to d2d user present position determine:

If d2d user is in the coverage of same cellulor, the system energy efficiency making macrocellular pattern is 0；

Otherwise, the system energy efficiency making cellulor pattern is 0.

3. the d2d communication means in macrocellular as claimed in claim 2 and cellulor heterogeneous network it is characterised in that according to The signal intensity that d2d user receives judges whether d2d user is in the coverage of same cellulor:

If the signal intensity of the macro base station that d2d user receives is less than the signal intensity from same little base station, judge that d2d uses Family is in same cellulor coverage；

Otherwise, it is determined that d2d user is in outside cellulor coverage.

4. the d2d communication means in macrocellular as claimed in claim 3 and cellulor heterogeneous network is it is characterised in that described System energy efficiency according to formula:

$\mathrm{\η}=\frac{c_1+c_2+c_3+c_4}{p\×w}$

Calculate, wherein:

c₁Represent the channel capacity of d2d user,

c₂Represent the channel capacity of the macrocell user that is re-used,

c₃Represent the overall channel capacity of all cellulor users that are re-used,

c₄Represent the overall channel capacity of all disturbed cellulor users,

P is the transmission power sum of all users in d2d communication system,

W is the channel width sum of all users in d2d communication system.

5. the d2d communication means in macrocellular as claimed in claim 4 and cellulor heterogeneous network is it is characterised in that 5 kinds The transmission power of d2d transmitting terminal under d2d communication pattern:

(a) dedicated mode:

(b) macrocellular pattern:

(c) multiplexing macrocellular channelling mode:

(d) cellulor pattern:

(e) multiplexing cellulor channelling mode:

Wherein, p_dRepresent the transmission power of d2d transmitting terminal, γ_dthFor the Signal to Interference plus Noise Ratio thresholding of d2d communication link, n₀For noise work( Rate spectrum density, h_abFor the channel gain between d2d user, h_abFor the channel gain between d2d transmitting terminal and macro base station,For D2d transmitting terminal and the channel gain between little base station, i belonging to it_mrFor the interference to d2d receiving terminal for the macrocell user that is re-used,For the interference to base station little belonging to d2d user for the disturbed cellulor user, i_srFor all cellulor users that are re-used to d2d The interference of receiving terminal, w_dChannel width for d2d transmitting terminal.

6. the d2d communication means in macrocellular as claimed in claim 5 and cellulor heterogeneous network is it is characterised in that d2d uses The channel capacity at family is according to formula:

c₁=w_dlog₂(1+γ_dth)

Calculate.

7. the d2d communication means in macrocellular as claimed in claim 6 and cellulor heterogeneous network is it is characterised in that answered Channel capacity c with macrocell user₂According to:

$c_2=w_{mr}{\log }_2(1+\frac{s_m}{i_{ab}+n_0{w}_{mr}})$

Calculate, wherein:

w_mrFor the channel width of the macrocell user that is re-used,

n₀For noise power spectral density,

s_mThe signal intensity from the macrocell user that is re-used receiving for macro base station,

i_abFor under the interference strength to macro base station for the d2d transmitting terminal, and multiplexing macrocellular channelling mode:

i_ab=p_dh_ab,

Under remaining d2d communication pattern: i_ab=0.

8. the d2d communication means in macrocellular as claimed in claim 7 and cellulor heterogeneous network is it is characterised in that own Be re-used cellulor user overall channel capacity according to formula:

$c_3=\underset{n=1}{\overset{n}{\σ}}{c}_s^n=\underset{n=1}{\overset{n}{\σ}}{w}_{sr}{\log }_2(1+\frac{s_n}{i_{as}^n+i_n+n_0{w}_{sr}})$

Calculate, wherein:

w_srFor the channel width of the cellulor user that is re-used,

N is to be re-used the number of cellulor user,

For the channel capacity of the cellulor user n that is re-used,

i_nThe interference coming from the cellulor user that other are re-used receiving for the little base station belonging to cellulor user n that is re-used Intensity,

For d2d transmitting terminal and the channel gain between little base station belonging to cellulor user n that is re-used,

s_nThe signal intensity from the cellulor user n that is re-used receiving for the little base station belonging to cellulor user n being re-used,

For the interference strength to the little base station belonging to cellulor user n that is re-used for the d2d transmitting terminal, and it is multiplexed cellulor channelling mode Under:

$i_{as}^n=p_d{h}_{as}^n,$

Under remaining d2d communication pattern:

9. the d2d communication means in macrocellular as claimed in claim 8 and cellulor heterogeneous network is it is characterised in that own The overall channel capacity of disturbed cellulor user is according to formula:

$c_4=\underset{r=1}{\overset{r}{\σ}}{c}_s^r=\underset{r=1}{\overset{r}{\σ}}{w}_s{\log }_2(1+\frac{s_r}{i_{as}^r+i_r+n_0{w}_s})$

Calculate, wherein:

w_sFor the channel width of disturbed cellulor user,

R is the number of disturbed cellulor user,

For the channel capacity of disturbed cellulor user r,

i_rThe interference coming from other disturbed cellulor users that little base station belonging to disturbed cellulor user r receives,

For d2d transmitting terminal and the channel gain between little base station belonging to disturbed cellulor user r,

s_rThe signal intensity from disturbed cellulor user r that little base station belonging to disturbed cellulor user r receives,

For the interference strength to the little base station belonging to cellulor user r that is re-used for the d2d transmitting terminal, and it is multiplexed cellulor channelling mode Under:

$i_{as}^r=p_d{h}_{as}^r,$

Under remaining d2d communication pattern:

10. the d2d communication means in macrocellular as claimed in claim 9 and cellulor heterogeneous network is it is characterised in that described D2d communication system in the channel width sum of all users be:

Under dedicated mode: w=w_de+w_mr+w_sr+w_s,

Under macrocellular pattern: w=2w_m+w_mr+w_sr+w_s,

Under other d2d communication patterns: w=w_mr+w_sr+w_s,

Wherein, w_deFor the bandwidth of the dedicated channel of d2d user, w_mDistribute to the channel width of d2d transmitting terminal for macrocellular.