CN104284404A - Method for lowering energy consumption of D2D system and macro base station - Google Patents

Abstract

The invention discloses a method for lowering the energy consumption of a D2D system and a macro base station. The method includes the steps that the macro base station receives geographic position information and service volume information, wherein the geographic position information and the service volume information are uploaded through a terminal; the macro base station obtains the dormancy threshold value of a small cell base station according to the geographic position information and the service volume information and sends the dormancy threshold value to the small cell base station so as to achieve dormancy or awakening for the small cell base station according to the load state of the small cell base station; the macro base station adjusts the ratio of the service volume information of a self-organization communication network to the service volume information of an auxiliary communication network according to the dormancy or the awakening of the small cell base station and the service volume information uploaded by the terminal. According to the method, by obtaining the geographic position coordinate information and the service volume information of the terminal, dormancy or awakening can be achieved for the small cell base station, the ratio of the service volume information of the self-organization communication network to the service volume information of the auxiliary communication network is adjusted, and by means of the method, the energy consumption of the system is lowered.

Description

Reduce method and the macro base station of D2D system energy consumption

Technical field

The present invention relates to communication technical field, be specifically related to a kind of method and the macro base station that reduce D2D system energy consumption.

Background technology

In the last few years, the fast development of wireless communication needs made the construction scale of its infrastructure huge, and its energy resource consumption produced and environmental pollution account for huge ratio in relevant data.According to statistics, in the whole world, annual consumed energy has accounted for 3 percent of all industry total amounts to industry to In-circiut tester (Information And Communications Technology is called for short ICT).As the result of energy resource consumption, its carbon dioxide isothermal chamber gas purging amount has also accounted for 2 percent.And increase fast with the growth rate of 10 five to percent two ten every year.

The energy consumption huge for communication network and potential energy-saving and emission-reduction space, the concept of " green radio communication " was proposed with industrial circle in recent years in academia, namely its object is by suitable network design and the network optimization, energy-saving and emission-reduction, reduces the power consumption of communication system.

Meanwhile, along with the day by day complicated of mobile radio network scale and the intelligent development of mobile terminal terminal, the requirement to system spectrum utilance and data rate is added.Therefore, a kind of terminal direct communication (D2D) recent years being different from conventional cellular communication pattern to obtain the extensive concern of 3GPP, and becomes LTE-R11, the discussion focus of LTE-R12.Lot of research for D2D communication shows, the D2D communication technology can greatly increase the spectrum reuse rate in community, thus increases power system capacity.But communication function can be concentrated on mobile phone terminal side by D2D communication to a greater degree, thus make its load larger, energy consumption is higher.Therefore, analyze the efficiency problem introduced under the cellular network of D2D scene and become very meaningful.

In addition, be different from traditional cell splitting strategy, in LTE and LTE-A, propose the concept of mixed networking.Namely, except traditional macro base station, coexist with the low power nodes of different stage in a network, to improve spatial frequency spectrum utilance, the especially capacity of hot spot region and speed.Wherein, the low-power operation node disposed in system can comprise as Microcell working terminal (Microcell), picocell working terminal (Picocell), Femto cell working terminal (Femtocell, also referred to as Home eNodeB), wireless relay working terminal (Relay) etc., the comparatively zonule, local of the covering macro cells of these low power nodes.

Solving the energy consumption problem in mobile communications network, with regard to needing, labor being carried out to the networking technology in current LTE-A.Along with the increase of traffic carrying capacity, network side needs constantly to expand its capacity, and before LTE, the method for employing is generally cell splitting, namely disposes macro base station with higher density.And the deployment very dense of current network node, make traditional cell splitting method critical constraints

Under current mobile communications network, except the uneven characteristic of distribution of traffic, it has great time variation toward contact, i.e. " tidal effect ".In a communications system, " tidal effect " refers at central business district (Central Business District, be called for short CBD), the region such as residential quarter, because terminal is regular or irregularly migrate mobile phenomenon on a large scale, in the mobile communication caused, telephone traffic is significantly shaken." tidal effect ", except bringing challenges to network burden, in efficiency, likely can cause the situation that specific cell underload is even unloaded.Due in practical communication system, most energy ezpenditure not at transmitting terminal, but consumes in base station static state, as new number process, and power supply, the aspects such as air-conditioning heat dissipation.If therefore base station operates to support small number of service, the situation that energy consumption loses more than gain can be caused.

Summary of the invention

For defect of the prior art, the invention provides a kind of method and the macro base station that reduce D2D system energy consumption, reach the object reducing system energy consumption.

First aspect, the invention provides a kind of method reducing D2D system energy consumption, comprising:

The geographical position coordinates information that macro base station receiving terminal is uploaded and traffic information;

Described macro base station is according to described geographical position coordinates information and traffic information, obtain the dormancy threshold values of small-cell base station, and sent to by described dormancy threshold values described small-cell base station to make described small-cell base station carry out dormancy according to the load condition of self or to wake up;

Described macro base station adjusts according to the dormancy of described small-cell base station or the traffic information that wakes up and upload according to the described terminal ratio to the traffic information of ad-hoc communication network and secondary communication path.

Optionally, the dormancy threshold values of described acquisition small-cell base station, and sent to by described dormancy threshold values described small-cell base station to make described small-cell base station carry out dormancy according to the load condition of self or to wake up, comprising:

Described small-cell base station periodicity or the acyclic load condition according to self carry out dormancy or wake up.

Optionally, the dormancy threshold values of described acquisition small-cell base station, and sent to by described dormancy threshold values described small-cell base station to make described small-cell base station carry out dormancy according to the load condition of self or to wake up, comprising:

Described small-cell base station carries out dormancy according to closedown expenditure power at a time and the closedown income power in this moment or wakes up.

Optionally, described small-cell base station carries out dormancy according to closedown expenditure power at a time and the closedown income power in this moment or wakes up, comprising:

If when described closedown expenditure power is less than described closedown income power, then described small-cell base station carries out dormancy;

If when described closedown expenditure power is greater than described closedown income power, then described small-cell base station wakes up.

Optionally, described macro base station adjusts according to the dormancy of described small-cell base station or the traffic information that wakes up and upload according to the described terminal ratio to the traffic information of ad-hoc communication network and secondary communication path, comprising:

Described macro base station obtains the total traffic information that described terminal is uploaded and the traffic information born for described macro base station assisted cell;

The total traffic information that described macro base station is uploaded according to described terminal and the traffic information born for described macro base station assisted cell, obtain the ratio distributing to the traffic information of described ad-hoc communication network and secondary communication path;

Described macro base station according to described in distribute to the ratio of the traffic carrying capacity of described ad-hoc communication network and the traffic information of secondary communication path, obtain the energy consumption function of described macro base station and the apex coordinate of described energy consumption function;

According to the value of apex coordinate and the dormancy of small-cell base station of described energy consumption function or wake up, adjust the ratio of the traffic information of described ad-hoc communication network and secondary communication path.

Second aspect, present invention also offers a kind of macro base station, comprising:

Receiver module, the geographical position coordinates information uploaded for receiving terminal and traffic information;

Sending module, for according to described geographical position coordinates information and traffic information, obtain the dormancy threshold values of small-cell base station, and sent to by described dormancy threshold values described small-cell base station to make described small-cell base station carry out dormancy according to the load condition of self or to wake up;

Adjusting module, for adjusting according to the dormancy of described small-cell base station or the traffic information that wakes up and upload according to the described terminal ratio to the traffic information of ad-hoc communication network and secondary communication path.

Optionally, described sending module, also for:

Described small-cell base station periodicity or the acyclic load condition according to self carry out dormancy or wake up.

Optionally, described sending module, also for:

Described small-cell base station carries out dormancy according to closedown expenditure power at a time and the closedown income power in this moment or wakes up.

Optionally, described sending module, also for:

When described closedown expenditure power is less than described closedown income power, then described small-cell base station carries out dormancy;

When described closedown expenditure power is greater than described closedown income power, then described small-cell base station wakes up.

Optionally, described adjusting module, comprising:

First acquiring unit, for obtaining the total traffic information that described terminal is uploaded and the traffic information born for described macro base station assisted cell;

Second acquisition unit, for the total traffic information uploaded according to described terminal and the traffic information born for described macro base station assisted cell, obtains the ratio distributing to the traffic information of described ad-hoc communication network and secondary communication path;

3rd acquiring unit, for the ratio of the traffic information of the traffic carrying capacity and secondary communication path of distributing to described ad-hoc communication network described in basis, obtains the energy consumption function of described macro base station and the apex coordinate of described energy consumption function;

Adjustment unit, for according to the value of apex coordinate and the dormancy of small-cell base station of described energy consumption function or wake up, adjusts the ratio of the traffic information of described ad-hoc communication network and secondary communication path.

As shown from the above technical solution, the method of reduction D2D system energy consumption provided by the invention and macro base station, the method is by obtaining geographical position coordinates information and the traffic information of terminal, small-cell base station is made to carry out dormancy or wake up, and the ratio of the traffic information of ad-hoc communication network and secondary communication path is adjusted, the method greatly reduces the energy consumption of system.

In specification of the present invention, describe a large amount of detail.But can understand, embodiments of the invention can be put into practice when not having these details.In some instances, be not shown specifically known method, structure and technology, so that not fuzzy understanding of this description.

Those skilled in the art can understand, although embodiments more described herein to comprise in other embodiment some included feature instead of further feature, the combination of the feature of different embodiment means and to be within scope of the present invention and to form different embodiments.Such as, in the following claims, the one of any of embodiment required for protection can use with arbitrary compound mode.

Last it is noted that above each embodiment is only in order to illustrate technical scheme of the present invention, be not intended to limit; Although with reference to foregoing embodiments to invention has been detailed description, those of ordinary skill in the art is to be understood that: it still can be modified to the technical scheme described in foregoing embodiments, or carries out equivalent replacement to wherein some or all of technical characteristic; And these amendments or replacement, do not make the essence of appropriate technical solution depart from the scope of various embodiments of the present invention technical scheme, it all should be encompassed in the middle of the scope of claim of the present invention and specification.

Accompanying drawing explanation

The flow chart of the method for the reduction D2D system energy consumption that Fig. 1 provides for one embodiment of the invention;

The structural representation of the communication network that Fig. 2 provides for one embodiment of the invention;

The structural representation of the macro base station that Fig. 3 provides for one embodiment of the invention;

The structural representation of adjusting module in the macro base station that Fig. 4 provides for one embodiment of the invention.

Embodiment

Below in conjunction with accompanying drawing, the embodiment of invention is further described.Following examples only for technical scheme of the present invention is clearly described, and can not limit the scope of the invention with this.

The present invention is mainly under the isomery scene of existing cellular community, the problem of system energy consumption outstanding problem, the present invention is by carrying out dormancy to small-cell base station or waking up, and the ratio of the traffic information of ad-hoc communication network and secondary communication path is adjusted, greatly system energy consumption reduced and optimize.

Fig. 1 shows the schematic flow sheet of the method reducing D2D system energy consumption, and as shown in Figure 1, the method comprises the steps:

101, the geographical position coordinates information uploaded of macro base station receiving terminal and traffic information.

102, described macro base station is according to described geographical position coordinates information and traffic information, obtain the dormancy threshold values of small-cell base station, and sent to by described dormancy threshold values described small-cell base station to make described small-cell base station carry out dormancy according to the load condition of self or to wake up.

For example, described small-cell base station periodicity or the acyclic load condition according to self carry out dormancy or wake up;

Described small-cell base station carries out dormancy according to closedown expenditure power at a time and the closedown income power in this moment or wakes up;

Concrete, if when described closedown expenditure power is less than described closedown income power, then described small-cell base station carries out dormancy;

If when described closedown expenditure power is greater than described closedown income power, then described small-cell base station wakes up.

103, described macro base station adjusts according to the dormancy of described small-cell base station or the traffic information that wakes up and upload according to the described terminal ratio to the traffic information of ad-hoc communication network and secondary communication path.

Said method is by obtaining geographical position coordinates information and the traffic information of terminal, small-cell base station is made to carry out dormancy or wake up, and the ratio of the traffic information of ad-hoc communication network and secondary communication path is adjusted, the method greatly reduces the energy consumption of system.

In order to more clearly demonstrate the present invention, be described in detail by following embodiment.

As shown in Figure 2, above-mentioned steps 101 specifically comprises the steps:

1011, the transmitter of each communication terminal is by the geographical position coordinates information of self, CMT wireless network temporary code (Radio Network Tempory Identity the is called for short RNTI) information of antenna configuration information and receiver sends to macro base station by upstream data shared channel.

1012, the geographical position coordinates information of macro base station to communication terminal is normalized mapping, specifically comprises the steps:

Total M terminal in 1012A, community, wherein: the number of transmitter terminals is T, the number of receiver terminal is R.Then have: M=T+R.

In addition, the geographical position transverse and longitudinal coordinate corresponding to each transmitter is: <x _t, y _t>.Wherein: 1≤t≤T.

Similarly, the geographical position transverse and longitudinal coordinate corresponding to each receiver is: <x _r, y _r>.Wherein: 1≤r≤R.

1012B, macro base station are normalized mapping to T transmitter, then the transmitter transverse and longitudinal coordinate position after normalization is:

$<x^T,y^T>=<\frac{1}{T}\&times;\underset{i=1}{\overset{T}{\mathrm{\&Sigma;}}}{x}_i,\frac{1}{T}\&times;\underset{i=1}{\overset{T}{\mathrm{\&Sigma;}}}{y}_i>$

Similarly, macro base station is normalized mapping to R receiver, then the receiver transverse and longitudinal coordinate position after normalization is:

$<x^R,y^R>=<\frac{1}{R}\&times;\underset{i=1}{\overset{R}{\mathrm{\&Sigma;}}}{x}_i,\frac{1}{R}\&times;\underset{i=1}{\overset{R}{\mathrm{\&Sigma;}}}{y}_i>$

Through above step, T transmitter is mapped as 1 transmitter and carries out process operation by macro base station approx.

Through above step, R receiver is mapped as 1 receiver and carries out process operation by macro base station approx.

Above-mentioned steps 102 specifically comprises the steps:

1021, macro base station carried out discrete sampling to one day 24 hours, and sampling number is Sample, then the moment sequence obtained is:

T _sample＝＜t ₁,t ₂……t _sample＞

1022, macro base station is according to T _samplesequence, calculates the parameter Δ P of its correspondence at specific timing node _mt (), wherein t is T _samplean element in sequence.Wherein, Δ P _mt () needs the transmitted power additionally paid for small-cell base station.

Particularly:

$\mathrm{\&Delta;}{P}_M\left(t\right)={(d_M/d_S)}^{\mathrm{\&alpha;}}{\mathrm{\&xi;}}_{\mathrm{PA}}{P}_S^T\left(t\right).$

Wherein: d _mfor macro base station radius of society size.D _sfor small-cell base station radius size.α is path-loss factor.ξ _pAfor power amplifier factor parameter, be defined as ξ _pA=1/ η (t).And for small-cell base station is in the power loss of t.

1023, macro base station is according to T _samplesequence, calculates the Parameter δ P of its correspondence at specific timing node _st (), wherein t is T _samplean element in sequence.Wherein, δ P _s(t) performance number for being saved by small-cell base station dormancy.

Particularly:

$\mathrm{\&delta;}{P}_S\left(t\right)=P_S^{\mathrm{All}}\left(t\right)-P_S^{\mathrm{Sleep}}$

Wherein, for the power loss that small-cell base station wakes up in t, for small-cell base station carries out the power loss of closing in t.

Usually, have:

$P_{\mathrm{BS},k}^{\mathrm{All}}\left(t\right)=\frac{P_{\mathrm{BS},k}^T\left(t\right)}{\mathrm{\&eta;}\left(t\right)}+P_{\mathrm{BS},k}^{\mathrm{Const}}$

Wherein, for base station is in the transmitting power of t, the power amplifier that η (t) is embedded in base station in the efficiency of t, for the constant power loss of base station, that includes as Base-Band Processing, the energy ezpenditure that air-conditioning equipment etc. are irrelevant with concrete service bearer amount.

1024, macro base station alignment parameters Δ P _m(t) and δ P _s(t), and then to whether carrying out the dormancy of small-cell base station or wake up.

Particularly, if Δ P _m(t) < δ P _stime (t), illustrate that small-cell base station is closed the system energy consumption that brings and reduced and be greater than macro cell base station and carry the additional energy that its traffic carrying capacity needs discharged pay.Then small-cell base station carries out dormancy.

Particularly, if Δ P _m(t) > δ P _stime (t), illustrate that small-cell base station is closed the system energy consumption that brings and reduced and be less than macro cell base station and carry the additional energy that its traffic carrying capacity needs discharged pay.Then small-cell base station wakes up.

Above-mentioned steps 103 specifically comprises the steps:

1031, described macro base station obtains the total traffic information that described terminal is uploaded and the traffic information born for described macro base station assisted cell;

1032, the total traffic information uploaded according to described terminal of described macro base station and the traffic information born for described macro base station assisted cell, obtain the ratio distributing to the traffic information of described ad-hoc communication network and secondary communication path;

For example, above-mentioned steps comprises the steps:

1032A, the macro base station total traffic value obtained in whole community is Load.

1032B, macro base station are Load_BS by calculating the traffic value that can be used for assisted cell to bear, then defined parameters λ _minfor:

${\mathrm{\&lambda;}}_{\min }=\frac{\mathrm{Load}-\mathrm{Load}\_\mathrm{BS}}{\mathrm{Load}}$

Namely the traffic carrying capacity ratio distributing to ad-hoc communication network (D2D network) is needed to be λ _min, and the traffic carrying capacity ratio needing assisted cell, base station to bear is 1-λ _min.

In addition, macro base station determines that the traffic peak ratio allowing D2D network assumes in community is λ _max.

1033, described macro base station according to described in distribute to the ratio of the traffic carrying capacity of described ad-hoc communication network and the traffic information of secondary communication path, obtain the energy consumption function of described macro base station and the apex coordinate of described energy consumption function;

For example, macro base station calculates energy consumption function: f ₁(θ, λ)=(1-λ) × f (θ, λ)

Wherein: θ be terminal transmitter to macro base station, the angle formed between macro base station to terminal receiver.

Coordinate according to having calculated terminal transmitter in above-mentioned steps 1012B is: < x ^t, y ^t>.The coordinate of terminal receiver is: < x ^r, y ^r>.

The geographical position coordinates of macro base station is: < x ^bS, y ^bS>.

Set following parameter:

$d_1=\sqrt{{(x^T-x^R)}^2+{(y^T-y^R)}^2}$

$d_2=\sqrt{{(x^T-x^{\mathrm{BS}})}^2+{(y^T-y^{\mathrm{BS}})}^2}$

$d_3=\sqrt{{(x^{\mathrm{BS}}-x^R)}^2+{(y^{\mathrm{BS}}-y^R)}^2}$

Then according to the trigonometric function cosine law, can calculate:

$\cos \mathrm{\&theta;}=\frac{d_2^2+d_3^2-d_1^2}{2d_2{d}_3}$

And then can in the hope of the value of θ, wherein d ₁for the distance between transmitted from transmitter to receiver, d ₂for the distance between transmitter to macro base station, d ₃for the distance between receiver to macro base station.

Particularly:

F (θ, λ) is unfolded as follows:

$\begin{array}{c}f(\mathrm{\&theta;},\mathrm{\&lambda;})=[E_{\mathrm{TCM}}-f_3\left(\mathrm{\&lambda;}\right)]-[E_{\mathrm{TCM}}-f_1\left(\mathrm{\&lambda;}\right)-f_2(\mathrm{\&theta;},\mathrm{\&lambda;})]\\ ={\&Integral;}_{T_{\mathrm{Off}}\left(\mathrm{\&lambda;}\right)}^T(K_S\&times;(\mathrm{\&delta;}{P}_S(t,\mathrm{\&lambda;})-\mathrm{\&Delta;}{P}_M(t,\mathrm{\&lambda;})))\mathrm{dt}\\ +\mathrm{\&phi;}\left(\mathrm{\&theta;}\right){\&Integral;}_0^T(P_M^T(t,\mathrm{\&lambda;})+K_S\&times;P_S^T(t,\mathrm{\&lambda;}))\mathrm{dt}\\ -{\&Integral;}_{T_{\mathrm{Off}}(\mathrm{\&lambda;}=0)}^T(K_S\&times;(\mathrm{\&delta;}{P}_S\left(t\right)-\mathrm{\&Delta;}{P}_M\left(t\right)))\mathrm{dt}\end{array}$

Wherein, E _tCMfor the overall network energy consumption under legacy cellular pattern (without dormancy strategy, without D2D communication), f ₃(λ) for there being dormancy strategy, under not adopting D2D communication pattern, its energy consumption of saving relative to legacy cellular pattern.Similarly, f ₁(λ)+f ₂(θ, λ) for there being dormancy strategy, under adopting D2D communication pattern, its energy consumption can saved relative to legacy cellular pattern (without dormancy strategy, communicating without D2D).T _off(λ) for D2D traffic carrying capacity ratio be λ time, small-cell enters the moment of dormancy, in addition, K _sfor the quantity of small-cell base station, δ P _s(t, λ) and Δ P _m(t, λ) is as follows:

$\mathrm{\&Delta;}{P}_M\left(t\right)={(d_M/d_S)}^{\mathrm{\&alpha;}}{\mathrm{\&xi;}}_{\mathrm{PA}}{P}_S^T\left(t\right)$

$\mathrm{\&delta;}{P}_S\left(t\right)=P_S^{\mathrm{All}}\left(t\right)-P_S^{\mathrm{Sleep}}$

as follows:

$\mathrm{\&phi;}\left(\mathrm{\&theta;}\right)=\frac{P_{\mathrm{UE},D2D}^T}{P_{\mathrm{UE},\mathrm{TCM}}^T+P_{\mathrm{BS}}^T}=\frac{d_1^{-\mathrm{\&alpha;}}}{2\&times;d_3^{-\mathrm{\&alpha;}}}={(1-\cos \mathrm{\&theta;})}^{\mathrm{\&alpha;}/2}$

Wherein, with the transmitting power of terminal in base station and DUE-G respectively,

it is the transmitting power being operated in terminal under legacy cellular pattern.

1034, according to the value of apex coordinate and the dormancy of small-cell base station of described energy consumption function or wake strategy up, the ratio of the traffic information of described ad-hoc communication network and secondary communication path is adjusted.

Concrete, curve f ₁the opening of (θ, λ) is upward constant, and f ₁(θ, 0)=0, then itself and λ axle have an intersection point (0,0) at least.Defined function f ₁the summit of (θ, λ) is: (λ _summit, f ₁(θ, λ _summit)), the value of its correspondence can obtain according to the computing formula of quadratic function.In addition, because function and λ axle have an intersection point (0,0) at least, the another one intersection point of definition quadratic function and λ axle is: (λ _x1, 0).

Then there are following three kinds of situations:

(1) λ is worked as _summitrepresent when≤0 that traffic value (Load_BS) that macro base station can be used for base station, assisted cell and bears is greater than macro base station and obtains total traffic value (Load) in whole community, function f ₁(θ, λ) be monotonic increase in the scope of the domain of definition [0,1] of λ, and function f ₁(θ, λ) value perseverance is greater than 0.Therefore, in this case, have dormancy strategy, the efficiency perseverance having D2D to communicate is better than dormancy strategy, without the efficiency of D2D communication.Then now the traffic carrying capacity ratio of D2D communication is λ in base station sets community _max.

(2) λ is worked as _summittime ∈ (0,1), in the scope of the domain of definition [0,1] of λ, function f ₁(θ, λ) first reduces to increase afterwards.

In addition, if λ _x1>=1, then there is dormancy strategy, will, always than there being dormancy strategy, having D2D communication efficiency good, because be always less than 0 in domain of definition inner function value without D2D communication.Then now, if λ _min≤ λ _summit≤ λ _max, in base station sets community, the traffic carrying capacity ratio of D2D communication is λ _summit.If λ _summit≤ λ _min≤ λ _max, then in base station sets community, the traffic carrying capacity ratio of D2D communication is λ _min.If λ _min≤ λ _max≤ λ _summit, then in base station sets community, the traffic carrying capacity ratio of D2D communication is λ _max.

If, λ _x1< 1, then functional value is at the domain of definition (λ _x1, 1) scope in will be greater than 0, show D2D communication be of value to Overall energy efficiency.Then now, in base station sets community, the traffic carrying capacity ratio of D2D communication is λ _summit, λ _maxthe minimum value of the system energy consumption that both are corresponding.

(3) λ is worked as _summitduring > 1, in the domain of definition, function f ₁the value of (θ, λ) is always less than 0, and therefore have dormancy strategy, without D2D communication always than there being dormancy strategy, the efficiency having D2D to communicate is good.In this case, from the angle of efficiency, D2D communication is not energy-conservation, then now the traffic carrying capacity ratio of D2D communication is λ in base station sets community _min.

Distance explanation is carried out below by with specific embodiment.

Suppose LTE isomery cellular network, comprise 1 macro base station, 5 small-cell (Small Cell) base stations, have 10 communication terminals in this LTE isomery cellular network.And communication object each other between 10 communication terminals.Macrocell radius is 250 meters, and the position coordinates of macro base station is (250,250).

Uploading of terminal positional information;

10 communication terminals are numbered:

UE1，UE2，……，UE10。

The CMT wireless network temporary code information of the geographical location information of self and receiver is fed back to macro base station by upstream data shared channel by the transmitter of each communication terminal.

Its reporting information is as shown in Table 1:

Table 1

Terminal number	RNTI	Location coordinate information
			UE1	12	(100,70)
UE2	16	(80,200)
			UE3	08	(400,260)
UE4	03	(130,60)
			UE5	02	(88,260)
UE6	07	(310,30)
			UE7	15	(10，250)
UE8	10	(280,280)
			UE9	06	(320,200)
UE10	01	(450,260)

The positional information of macro base station to communication terminal is normalized mapping;

Have 10 terminals in small-cell, wherein: the number of transmitter terminals is 5, the number of receiver is 5.The transmitting-receiving relation of communication is as follows:

5 transmitters: UE1, UE2, UE3, UE4, UE5;

5 corresponding receivers: UE6, UE7, UE8, UE9, UE10.

Macro base station is normalized mapping to 5 transmitters, then the transmitter transverse and longitudinal coordinate position after normalization is:

$<x^T,y^T>=<\frac{1}{T}\&times;\underset{i=1}{\overset{T}{\mathrm{\&Sigma;}}}{x}_i,\frac{1}{T}\&times;\underset{i=1}{\overset{T}{\mathrm{\&Sigma;}}}{y}_i>$

The transverse and longitudinal coordinate figure of UE1 to UE5 is substituted into above-mentioned formula, then has:

＜x ^T,y ^T＞＝<159.6,170>。

Similarly, macro base station is normalized mapping to 5 receivers (UE6 to UE10), then the receiver transverse and longitudinal coordinate position after normalization is:

＜x ^R,y ^R＞＝<274,204>

Through above step, 5 transmitters are mapped as 1 transmitter and carry out process operation by macro base station approx.

Through above step, 5 receivers are mapped as 1 receiver and carry out process operation by macro base station approx.

Macro base station carries out community switch according to own service amount loading condition and closes;

Macro base station carried out discrete sampling to one day 24 hours, and sampling number is Sample=240, and namely in one day, macro base station carries out 240 operations to small-cell base station dormancy or wake up, and in one day, 240 trials in base station carry out dynamic conditioning to traffic carrying capacity.The moment sequence then obtained is:

T _sample＝＜t ₁,t ₂……t ₂₄₀＞

Macro base station is according to T _samplesequence, calculates the parameter Δ P of its correspondence at 240 corresponding timing nodes _mt (), wherein t is T _samplean element in sequence.

Particularly:

$\mathrm{\&Delta;}{P}_M\left(t\right)={(d_M/d_S)}^{\mathrm{\&alpha;}}{\mathrm{\&xi;}}_{\mathrm{PA}}{P}_S^T\left(t\right).$

Wherein: d _mfor macro base station radius of society size.D _sfor small-cell base station radius size.α is path-loss factor.ξ _pAfor power amplifier factor parameter, be defined as ξ _pA=1/ η (t).And for small-cell base station is in the power loss of t.

In the present embodiment, with t ₁moment is example, d _m=250, d _s=50.Path-loss factor α=1.0.In this moment, efficiency power amplifier η (t ₁)=0.5, then power amplifier factor parameter is ξ _pA=2.0.In addition,

Then, can obtain through calculating:

$\mathrm{\&Delta;}{P}_M\left(t\right)={(d_M/d_S)}^{\mathrm{\&alpha;}}{\mathrm{\&xi;}}_{\mathrm{PA}}{P}_S^T\left(t\right)=5*2.0*10=100$

Macro base station is according to T _samplesequence, calculates the parameter base station calculating parameter δ P of its correspondence at specific timing node _st (), wherein t is T _samplean element in sequence.

Particularly:

$\mathrm{\&delta;}{P}_S\left(t\right)=P_S^{\mathrm{All}}\left(t\right)-P_S^{\mathrm{Sleep}}$

Wherein, for the power loss that small-cell base station wakes up in t, for small-cell base station to carry out the power loss of dormancy in t.

Usually, have:

$P_{\mathrm{BS},k}^{\mathrm{All}}\left(t\right)=\frac{P_{\mathrm{BS},k\left(t\right)}^T}{\mathrm{\&eta;}\left(t\right)}+P_{\mathrm{BS},k}^{\mathrm{Const}}$

Wherein, for base station is in the transmitting power of t, the power amplifier that η (t) is embedded in base station in the efficiency of t, for the constant power loss of base station, that includes as Base-Band Processing, the energy ezpenditure that air-conditioning equipment etc. are irrelevant with concrete service bearer amount.

In the present embodiment, with t ₁moment is example, now, has:

Efficiency power amplifier η (t ₁)=0.5, $P_S^T\left(t_1\right)=10,P_S^{\mathrm{Const}}=2.0,P_S^{\mathrm{Sleep}}=1.0$

Then can calculate:

$P_S^{\mathrm{All}}\left(t_1\right)=10/0.5+2.0=22.$

Further, have:

$\mathrm{\&delta;}{P}_S\left(t\right)=P_S^{\mathrm{All}}\left(t\right)-P_S^{\mathrm{Sleep}}=21$

Macro base station alignment parameters Δ P _m(t) and δ P _s(t), and then wake up or dormancy whether carrying out small-cell base station.

In the present embodiment, have

ΔP _M(t)＝100

δP _S(t)＝21

Then there is Δ P _m(t) > δ P _st (), illustrates that small-cell base station is closed the system energy consumption that brings and reduced and be less than macro cell base station and carry the additional energy that its traffic carrying capacity needs discharged pay.Then small-cell base station is original is closed condition, then wake decision-making up to it, if small-cell base station original be exactly opening, then do not operate on it.

Macro base station carries out traffic carrying capacity adjustment between auxiliary cellular network and self-organizing cellular network, to make energy consumption more excellent;

The macro base station total traffic value obtained in whole community is Load=100.

Macro base station is Load_BS=50 by calculating the traffic value that can be used for assisted cell to bear, then defined parameters λ _minfor:

${\mathrm{\&lambda;}}_{\min }=\frac{\mathrm{Load}-\mathrm{Load}\_\mathrm{BS}}{\mathrm{Load}}=\frac{100-50}{100}=0.5$

Namely the traffic carrying capacity ratio distributing to ad-hoc communication network (D2D network) is needed to be λ _min=0.5, and the traffic carrying capacity ratio needing assisted cell, base station to bear is 1-λ _min=0.5.

In addition, macro base station determines that the traffic peak ratio allowing D2D network assumes in community is λ _max=0.8.

Macro base station calculates energy consumption function: f ₁(θ, λ)=(1-λ) × f (θ, λ)

Wherein: θ be terminal transmitter to base station, the angle formed between base station to terminal receiver.

In above-mentioned steps, the coordinate having calculated terminal transmitter is:

＜x ^T,y ^T＞＝<159.6,170>。

The coordinate of terminal receiver is:

＜x ^R,y ^R＞＝<274,204>

The geographical position coordinates of macro base station is: < x ^bS, y ^bS>=<250,250>.

Set following parameter:

$d_1=\sqrt{{(x^T-x^R)}^2+{(y^T-y^R)}^2}=119.3455$

$d_2=\sqrt{{(x^T-x^{\mathrm{BS}})}^2+{(y^T-y^{\mathrm{BS}})}^2}=120.7152$

$d_3=\sqrt{{(x^{\mathrm{BS}}-x^R)}^2+{(y^{\mathrm{BS}}-y^R)}^2}=51.8845$

Then according to the trigonometric function cosine law, can calculate:

$\cos \mathrm{\&theta;}=\frac{d_2^2+d_3^2-d_1^2}{2d_2{d}_3}=0.2149$

And then can be in the hope of the value of θ:

θ＝77.6293

Particularly:

F (θ, λ) is unfolded as follows:

$\begin{array}{c}f(\mathrm{\&theta;},\mathrm{\&lambda;})=[E_{\mathrm{TCM}}-f_3\left(\mathrm{\&lambda;}\right)]-[E_{\mathrm{TCM}}-f_1\left(\mathrm{\&lambda;}\right)-f_2(\mathrm{\&theta;},\mathrm{\&lambda;})]\\ ={\&Integral;}_{T_{\mathrm{Off}}\left(\mathrm{\&lambda;}\right)}^T(K_S\&times;(\mathrm{\&delta;}{P}_S(t,\mathrm{\&lambda;})-\mathrm{\&Delta;}{P}_M(t,\mathrm{\&lambda;})))\mathrm{dt}\\ +\mathrm{\&phi;}\left(\mathrm{\&theta;}\right){\&Integral;}_0^T(P_M^T(t,\mathrm{\&lambda;})+K_S\&times;P_S^T(t,\mathrm{\&lambda;}))\mathrm{dt}\\ -{\&Integral;}_{T_{\mathrm{Off}}(\mathrm{\&lambda;}=0)}^T(K_S\&times;(\mathrm{\&delta;}{P}_S\left(t\right)-\mathrm{\&Delta;}{P}_M\left(t\right)))\mathrm{dt}\end{array}$

Wherein, E _tCMfor the overall network energy consumption under legacy cellular pattern (without dormancy strategy, without D2D communication), f ₃(λ) for there being dormancy strategy, under not adopting D2D communication pattern, its energy consumption of saving relative to legacy cellular pattern.Similarly, f ₁(λ)+f ₂(θ, λ) for there being dormancy strategy, under adopting D2D communication pattern, its energy consumption can saved relative to legacy cellular pattern (without dormancy strategy, communicating without D2D).T _off(λ) for D2D traffic carrying capacity ratio be λ time, small-cell enters the moment of dormancy, specifically can be obtained by step 3.In addition, K _sfor the quantity of small-cell, in the present embodiment, its value is 5.δ P _s(t, λ) and Δ P _m(t, λ) is as follows:

$\mathrm{\&Delta;}{P}_M\left(t\right)={(d_M/d_S)}^{\mathrm{\&alpha;}}{\mathrm{\&xi;}}_{\mathrm{PA}}{P}_S^T\left(t\right)$

$\mathrm{\&delta;}{P}_S\left(t\right)=P_S^{\mathrm{All}}\left(t\right)-P_S^{\mathrm{Sleep}}$

as follows:

$\mathrm{\&phi;}\left(\mathrm{\&theta;}\right)=\frac{P_{\mathrm{UE},D2D}^T}{P_{\mathrm{UE},\mathrm{TCM}}^T+P_{\mathrm{BS}}^T}=\frac{d_1^{-\mathrm{\&alpha;}}}{2\&times;d_3^{-\mathrm{\&alpha;}}}={(1-\cos \mathrm{\&theta;})}^{\mathrm{\&alpha;}/2}$

Wherein, with the transmitting power of terminal in macro base station and DUE-G respectively, it is the transmitting power being operated in terminal under legacy cellular pattern.

Then in the present embodiment, through calculating, energy consumption function: f ₁the expression formula of (θ, λ)=(1-λ) × f (θ, λ) is:

f ₁(θ＝77.6293,λ)＝3λ ²-4λ

Macro base station carries out relative adjustment to ad-hoc communication network side with the traffic value of secondary communication path side, base station, makes efficiency more excellent.Concrete method of adjustment is as follows:

Curve f ₁the opening of (θ, λ) is upward constant.In addition, due to f ₁(θ, 0)=0, then itself and λ axle have an intersection point (0,0) at least.Then our defined function f ₁the summit of (θ, λ) is: (λ _summit, f ₁(θ, λ _summit)), the value of its correspondence can obtain according to the computing formula of quadratic function.In addition, because function and λ axle have an intersection point (0,0) at least, the another one intersection point of definition quadratic function and λ axle is: (λ _x1, 0).

Then:

In the present embodiment, function f can be calculated ₁the summit of (θ, λ) is: (λ _summit, f ₁(θ, λ _summit))=(0.6667 ,-1.3333), the another one intersection point of itself and λ axle is: (1.3333,0).

Then have, in the present embodiment:

λ _summit∈ (0,1), in the scope of the domain of definition [0,1] of λ, function f ₁(θ, λ) first reduces to increase afterwards.

And have, λ _x1> 1, then have dormancy strategy, will, always than there being dormancy strategy, have D2D communication efficiency good, because be always less than 0 in domain of definition inner function value without D2D communication.Then now, due to λ _min≤ λ _summit≤ λ _max, then in base station sets community, the traffic carrying capacity ratio of D2D communication is λ _summit=0.6667.

Fig. 3 shows a kind of macro base station, and as shown in Figure 3, above-mentioned macro base station comprises: receiver module 31, sending module 32 and adjusting module 33;

Receiver module 31, the geographical position coordinates information uploaded for receiving terminal and traffic information;

Sending module 32, for according to described geographical position coordinates information and traffic information, obtain the dormancy threshold values of small-cell base station, and sent to by described dormancy threshold values described small-cell base station to make described small-cell base station carry out dormancy according to the load condition of self or to wake up;

Adjusting module 33, for adjusting according to the dormancy of described small-cell base station or the traffic information that wakes up and upload according to the described terminal ratio to the traffic information of ad-hoc communication network and secondary communication path.

Described sending module, also for:

Described small-cell base station periodicity or the acyclic load condition according to self carry out dormancy or wake up.

Described sending module, also for:

Described small-cell base station carries out dormancy according to closedown expenditure power at a time and the closedown income power in this moment or wakes up.

Concrete, when described closedown expenditure power is less than described closedown income power, then described small-cell base station carries out dormancy;

When described closedown expenditure power is greater than described closedown income power, then described small-cell base station wakes up.

Above-mentioned adjusting module as shown in Figure 4, comprising: the first acquiring unit 41, second acquisition unit 42, the 3rd acquiring unit 43 and adjustment unit 44.

First acquiring unit 41, for obtaining the total traffic information that described terminal is uploaded and the traffic information born for described macro base station assisted cell;

Second acquisition unit 42, for the total traffic information uploaded according to described terminal and the traffic information born for described macro base station assisted cell, obtains the ratio distributing to the traffic information of described ad-hoc communication network and secondary communication path;

3rd acquiring unit 43, for the ratio of the traffic information of the traffic carrying capacity and secondary communication path of distributing to described ad-hoc communication network described in basis, obtains the energy consumption function of described macro base station and the apex coordinate of described energy consumption function;

Adjustment unit 44, for according to the value of apex coordinate and the dormancy of small-cell base station of described energy consumption function or wake up, adjusts the ratio of the traffic information of described ad-hoc communication network and secondary communication path.

Claims (10)

1. reduce a method for D2D system energy consumption, it is characterized in that, comprising:

The geographical position coordinates information that macro base station receiving terminal is uploaded and traffic information;

Described macro base station is according to described geographical position coordinates information and traffic information, obtain the dormancy threshold values of small-cell base station, and sent to by described dormancy threshold values described small-cell base station to make described small-cell base station carry out dormancy according to the load condition of self or to wake up;

Described macro base station adjusts according to the dormancy of described small-cell base station or the traffic information that wakes up and upload according to the described terminal ratio to the traffic information of ad-hoc communication network and secondary communication path.

2. method according to claim 1, is characterized in that, the dormancy threshold values of described acquisition small-cell base station, and is sent to by described dormancy threshold values described small-cell base station to make described small-cell base station carry out dormancy according to the load condition of self or to wake up, comprising:

Described small-cell base station periodicity or the acyclic load condition according to self carry out dormancy or wake up.

3. method according to claim 2, is characterized in that, the dormancy threshold values of described acquisition small-cell base station, and is sent to by described dormancy threshold values described small-cell base station to make described small-cell base station carry out dormancy according to the load condition of self or to wake up, comprising:

Described small-cell base station carries out dormancy according to closedown expenditure power at a time and the closedown income power in this moment or wakes up.

4. method according to claim 3, is characterized in that, described small-cell base station carries out dormancy according to closedown expenditure power at a time and the closedown income power in this moment or wakes up, comprising:

If when described closedown expenditure power is less than described closedown income power, then described small-cell base station carries out dormancy;

If when described closedown expenditure power is greater than described closedown income power, then described small-cell base station wakes up.

5. method according to claim 1, it is characterized in that, described macro base station adjusts according to the dormancy of described small-cell base station or the traffic information that wakes up and upload according to the described terminal ratio to the traffic information of ad-hoc communication network and secondary communication path, comprising:

Described macro base station obtains the total traffic information that described terminal is uploaded and the traffic information born for described macro base station assisted cell;

The total traffic information that described macro base station is uploaded according to described terminal and the traffic information born for described macro base station assisted cell, obtain the ratio distributing to the traffic information of described ad-hoc communication network and secondary communication path;

Described macro base station according to described in distribute to the ratio of the traffic carrying capacity of described ad-hoc communication network and the traffic information of secondary communication path, obtain the energy consumption function of described macro base station and the apex coordinate of described energy consumption function;

According to the value of apex coordinate and the dormancy of small-cell base station of described energy consumption function or wake up, adjust the ratio of the traffic information of described ad-hoc communication network and secondary communication path.

6. a macro base station, is characterized in that, comprising:

Receiver module, the geographical position coordinates information uploaded for receiving terminal and traffic information;

Sending module, for according to described geographical position coordinates information and traffic information, obtain the dormancy threshold values of small-cell base station, and sent to by described dormancy threshold values described small-cell base station to make described small-cell base station carry out dormancy according to the load condition of self or to wake up;

Adjusting module, for adjusting according to the dormancy of described small-cell base station or the traffic information that wakes up and upload according to the described terminal ratio to the traffic information of ad-hoc communication network and secondary communication path.

7. macro base station according to claim 6, is characterized in that, described sending module, also for:

Described small-cell base station periodicity or the acyclic load condition according to self carry out dormancy or wake up.

8. macro base station according to claim 7, is characterized in that, described sending module, also for:

Described small-cell base station carries out dormancy according to closedown expenditure power at a time and the closedown income power in this moment or wakes up.

9. macro base station according to claim 8, is characterized in that, described sending module, also for:

When described closedown expenditure power is less than described closedown income power, then described small-cell base station carries out dormancy;

When described closedown expenditure power is greater than described closedown income power, then described small-cell base station wakes up.

10. macro base station according to claim 6, is characterized in that, described adjusting module, comprising:

First acquiring unit, for obtaining the total traffic information that described terminal is uploaded and the traffic information born for described macro base station assisted cell;

Second acquisition unit, for the total traffic information uploaded according to described terminal and the traffic information born for described macro base station assisted cell, obtains the ratio distributing to the traffic information of described ad-hoc communication network and secondary communication path;

3rd acquiring unit, for the ratio of the traffic information of the traffic carrying capacity and secondary communication path of distributing to described ad-hoc communication network described in basis, obtains the energy consumption function of described macro base station and the apex coordinate of described energy consumption function;

Adjustment unit, for according to the value of apex coordinate and the dormancy of small-cell base station of described energy consumption function or wake up, adjusts the ratio of the traffic information of described ad-hoc communication network and secondary communication path.