CN103442420B - High energy efficiency method for optimizing resources based on advance and retreat method and Fibonacci method - Google Patents

Abstract

The invention discloses a kind of high energy efficiency method for optimizing resources based on advance and retreat method and Fibonacci method, be included in and ensure that D2D user, under the optimum prerequisite of efficiency on shared frequency spectrum resource, has set up the Mathematical Modeling of D2D communication system efficiency; Find that by analysis this Mathematical Modeling can be decomposed into two-layer independently optimization problem: ground floor is power control, the second layer is that resource is distributed; In ground floor optimization problem, first consider that every group of D2D user is optimized self efficiency respectively in feasible resource separately, and prove that corresponding efficiency function has and successively decrease or first increase progressively the character of successively decreasing afterwards, just necessarily there is optimal solution in it, adopts advance and retreat method and Fibonacci method to try to achieve optimal solution; A kind of heuristic resource allocation algorithm has been proposed in second layer optimization problem. The present invention can improve mobile communication D2D system energy efficiency, meets green communications and extends the battery of mobile terminal requirement of service time.

Description

High energy efficiency method for optimizing resources based on advance and retreat method and Fibonacci method

Technical field

The present invention relates to mobile communication resources and distribute and power control techniques, relate in particular to the straight-through cellular communication of a kind of terminal systemHigh energy efficiency method for optimizing resources based on advance and retreat method and Fibonacci method in system.

Background technology

At present, for solving frequency spectrum resource anxiety and improving traffic rate, the common employing speed of people D2D high, low in energy consumption(device-to-device) technology, i.e. the straight-through technology of cellular terminal, but D2D technology has strengthened phone user to D2DUser's interference and D2D user disturb cellular link, thereby reduce the data transmission rate between communication.

Along with green communications receive people's concern day by day, how distribute by resource and power control to improve D2D systemThe efficiency of system is that current D2D technology is urgently to be resolved hurrily.

Summary of the invention

Goal of the invention: in order to overcome the deficiencies in the prior art, the invention provides the straight-through cellular communication of a kind of terminal systemHigh energy efficiency method for optimizing resources based on advance and retreat method and Fibonacci method in system, improves D2D system energy efficiency.

Technical scheme: for achieving the above object, the technical solution used in the present invention is:

High energy efficiency method for optimizing resources based on advance and retreat method and Fibonacci method, is included in and ensures that D2D user is certainly in instituteTake on frequency spectrum resource under the optimum prerequisite of efficiency, set up the Mathematical Modeling of D2D communication system efficiency; Send out by analysisNow this Mathematical Modeling can be decomposed into two-layer independently optimization problem: ground floor is power control, and the second layer is that resource is distributed;In ground floor optimization problem, first consider that every group of D2D user enters self efficiency respectively in feasible resource separatelyRow is optimized, and has proved that corresponding efficiency function has and successively decrease or first increase progressively the character of successively decreasing afterwards, and it is certain existence justExcellent solution, adopts advance and retreat method and Fibonacci method to try to achieve optimal solution; A kind of heuristic money has been proposed in second layer optimization problemSource allocation algorithm. Comprise the steps:

(1) set up the object function of efficiency, suc as formula (1)

$\max U_{EE}=\underset{i=1}{\overset{N_d}{\Σ}}\frac{\underset{j=1}{\overset{M}{\Σ}}{x}_{i,j}\·R\left(p_{i,j}\right)}{\underset{j=1}{\overset{M}{\Σ}}{x}_{i,j}\·p_{i,j}+P_C}---\left(1\right)$

This object function comprises following constraints:

1. every group of minimum transmission rate request that D2D is right, minimum transfer rate can not be less than γ_i, not D2D on the same groupRight minimum transfer rate can be different, to meet business need:

$R\left(p_{i,j}\right)\≥{\mathrm{\γ}}_i,\∀i,\∀j$

2. with one group of D2D to sharing the phone user of same resource block two D2D users' to this group D2D centeringJamming power must be less than certain value τ, and the interference of bearing due to reception user is larger, generally can think receiving userJamming power must be less than certain value τ:

$p_{I,k,i}\·h_{k,i}\≤\mathrm{\τ},\∀x_{i,j}=1$

③x_i,jGet 1 expression i group D2D multiplexing to selecting j Resource Block to carry out, x_i,jGet 0 expression i group D2DTo not selecting j Resource Block to carry out multiplexing:

$x_{i,j}\∈\{0,1\},\∀i,\∀j$

4. every group of D2D is to Resource Block that can and can only a multiplexing phone user:

$\underset{j=1}{\overset{M}{\Σ}}{x}_{i,j}=1,\∀i$

5. each phone user's Resource Block at most can only be by one group of D2D to multiplexing:

$\underset{i=1}{\overset{N_d}{\Σ}}{x}_{i,j}\≤1,\∀j$

6. D2D user's maximum transmission power limits:

$0\≤p_{i,j}\≤p_{max},\∀i,\∀j$

Every group of D2D centering comprises two D2D users, and one of them is for receiving user, and another is for sending user;

Wherein: N_dRepresent the right group number of D2D, M represents the number of allowable resource piece, and i represents i group D2D couple,J represents j Resource Block, and k represents the sequence number with the phone user of i group D2D to multiplexing same resource block; U_EETableShow the efficiency sum that all D2D are right;Represent that i group D2D is to multiplexingSpeed when j Resource Block; p_i,jRepresent that i group D2D is to the through-put power on j Resource Block, P_CRepresentThe power (not being subject to the impact of D2D on through-put power) that on mobile terminal, circuit consumes, w represents the bandwidth of Resource Block,h_D,iRepresent same group of D2D centering transmitting user and receive the channel gain between user, p_I,k,iRepresent and one group of D2DThe transmitting power of phone user to shared resource piece, h_k,iRepresent to share phone user and the D2D centering of same Resource BlockReception user between channel gain, σ²Represent the variance of white Gaussian noise;

(2) if x_i,jGet definite value, just removed D2D in former optimization problem between coupling, divide by object functionBecome two-layer independently optimization problem, wherein ground floor optimization problem is Power Control Problem, and second layer optimization problem is resourceAssignment problem;

(3), in ground floor optimization problem, every group of D2D is to the efficiency function U (p on fixed resource_i,j) be expressed as:

$U\left(p_{i,j}\right)=\frac{R\left(p_{i,j}\right)}{p_{i,j}+P_C}=\frac{w\·{\log }_2(1+\frac{p_{i,j}\·h_{D,i}}{p_{I,k,i}\·h_{k,i}+{\mathrm{\σ}}^2})}{p_{i,j}+P_C},\∀i,\∀j---\left(2\right)$

This efficiency function has and successively decreases or first increase progressively the character of successively decreasing afterwards, and every group of D2D is to adopting separately advance and retreat method and goldSplit plot design is tried to achieve optimal solution separately;

(4) in second layer optimization problem, adopt heuristic resource allocation algorithm to carry out resource distribution, determine every group of D2DTo multiplexing resource.

In described step (4), the Mathematical Modeling of second layer optimization problem is:

$max\underset{i=1}{\overset{N_d}{\Σ}}\underset{j=1}{\overset{M^{\′}}{\Σ}}{x}_{i,j}U\left(p_{i,j}^{*}\right)---\left(3\right)$

This Mathematical Modeling comprises following constraints:

$\underset{j=1}{\overset{M}{\Σ}}{x}_{i,j}=1,\∀i$

$\underset{i=1}{\overset{N_d}{\Σ}}{x}_{i,j}\≤1,\∀j$

$x_{i,j}\∈\{0,1\},\∀i,\∀j$

Wherein:Represent the optimum efficiency value obtaining in ground floor optimization problem, the result of utilizing ground floor to optimizeAdopt heuristic resource allocation algorithm to carry out resource distribution, specifically comprise the steps:

4a). by every group of D2D to the efficiency U (p in each available resources_i,j) sort from big to small;

4b). first allow every group of D2D all take and can imitate U (p_i,j) maximum resource;

4c). find out resource and the D2D couple of conflict;

4d). resource and the D2D centering of conflict, calculate every group of D2D to adopting efficiency U (p_i,j) the resource institute of taking second placeThe efficiency loss causing, distributes to efficiency by the resource of conflict and loses maximum D2D couple, and all the other D2D are to multiplexing efficiencyThe resource of taking second place;

4e). repeat 4c)～4d), until D2D does not conflict to multiplexing resource.

Always there is a unique through-put power p of global optimum for formula (2)_i,jMake U (p_i,j) reach maximum, proveProcess following (will using the concept of concavity in proof procedure):

Definition: one by n tie up DUAL PROBLEMS OF VECTOR MAPPING in real number convex set D become the function f of a real number be intend recessed, ifFor x arbitrarily₁,x₂∈ D and x₁≠x₂Have:

f(λx₁+(1-λ)x₂)>min{f(x₁),f(x₂)}

Wherein, 0 < λ < 1; First can be in the hope of R (p_i,j) second dervativeItsInSo known R (p_i,j) about p_i,jA strict concave function, definition U (p_i,j)Superlevel collection is as follows:

S_β＝{p_i,j>0|U(p_i,j)≥β}

If for any real number β, S_βA strict convex set, U (p_i,j) about p_i,jIt is a recessed letter of strict planNumber; In the time of β<0, on border, there is no some S in the time of β>=0_β＝{p_i,j>0|β·(p_i,j+P_{C_ave})-R_i(p_i,j)≤0}; CauseFor R (p_i,j) about p_i,jStrict concave function, S_βAbout p_i,jIt is Strict Convex; This has just proved U (p_i,j) be aboutp_i,jStrictly quasi-concave function; U (p again_i,j) first derivative as follows:

$\frac{dU\left(p_{i,j}\right)}{{\mathrm{dp}}_{i,j}}=w\&CenterDot;\&lsqb;\frac{y_i+y_c}{(1+y_i)\ln 2}-{\log }_2(1+y_i)\&rsqb;/{(p_{i,j}+P_C)}^2=\mathrm{\&theta;}\left(p_{i,j}\right)/{(p_{i,j}+P_C)}^2$

Wherein $y_c=\frac{P_C\&CenterDot;h_{i,i}}{p_{C,k,i}\&CenterDot;h_{k,i}+{\mathrm{\&sigma;}}^2},$ θ(p_i,j) first derivative be ${\mathrm{\&theta;}}^{\&prime;}\left(p_{i,j}\right)=-\frac{\mathrm{\&lambda;}(y_i+y_c)}{{(1+y_i)}^{2}ln2}<0,$ Thereforeθ(p_i,j) be monotone decreasing;Obvious, (1 °) whenTime, U (p_i,j) beFirst monotonic increase monotone decreasing again; (2 °) whenU(p_i,j) be monotone decreasing, so U (p_i,j)At p_i,j＝p_initialPoint is obtained maximum, so certainly exist a unique through-put power p of global optimum_i,jMakeU(p_i,j) reach maximum.

Beneficial effect: the high energy efficiency method for optimizing resources based on advance and retreat method and Fibonacci method provided by the invention, set upUnder ensureing that every group of D2D is to the optimum prerequisite of efficiency on shared frequency spectrum resource, all D2D users' Mathematical Modeling,And the complicated optimum problem of former coupling has been resolved into bilevel optimization problem, bring great convenience for solving; ConsideringWhen D2D user self efficiency, allow every group of D2D user all be operated in its efficiency optimum point; Considering to introduce every group of D2DWhen the corresponding efficiency of user, also take into account the efficiency of overall D2D system, and made by heuristic resource allocation algorithmObtain overall efficiency optimum.

Brief description of the drawings

Fig. 1 is principle flow chart of the present invention.

Detailed description of the invention

Below in conjunction with accompanying drawing, the present invention is further described.

Be illustrated in figure 1 a kind of high energy efficiency method for optimizing resources based on advance and retreat method and Fibonacci method, comprise in simple termsFollowing steps:

1) every group of D2D be to perception interference to it from phone user on different resource respectively, and it is little to select jamming powerIn the resource of certain threshold value, as feasible set of resources;

2) every group of D2D be to first obtaining by advance and retreat method the interval that comprises optimal power point respectively, then obtain by Fibonacci methodIts efficiency optimum point (being transmitting power) and corresponding efficiency value in feasible set of resources;

3) every group of D2D user by it efficiency optimum point in each feasible set of resources and corresponding efficiency value pass to base station.

4) base station adopts heuristic resource allocation algorithm finally to determine every group of resource that D2D user is multiplexing.

The specific implementation process of the method is as follows:

(1) set up the object function of efficiency, suc as formula (1)

$\max U_{EE}=\underset{i=1}{\overset{N_d}{\&Sigma;}}\frac{\underset{j=1}{\overset{M}{\&Sigma;}}{x}_{i,j}\&CenterDot;R\left(p_{i,j}\right)}{\underset{j=1}{\overset{M}{\&Sigma;}}{x}_{i,j}\&CenterDot;p_{i,j}+P_C}---\left(1\right)$

This object function comprises following constraints:

1. every group of minimum transmission rate request that D2D is right, minimum transfer rate can not be less than γ_i, not D2D on the same groupRight minimum transfer rate can be different, to meet business need:

$R\left(p_{i,j}\right)\&GreaterEqual;{\mathrm{\&gamma;}}_i,\&ForAll;i,\&ForAll;j$

2. with one group of D2D to sharing the phone user of same resource block two D2D users' to this group D2D centeringJamming power must be less than certain value τ, and the interference of bearing due to reception user is larger, generally can think receiving userJamming power must be less than certain value τ:

$p_{I,k,i}\&CenterDot;h_{k,i}\&le;\mathrm{\&tau;},\&ForAll;x_{i,j}=1$

③x_i,jGet 1 expression i group D2D multiplexing to selecting j Resource Block to carry out, x_i,jGet 0 expression i group D2DTo not selecting j Resource Block to carry out multiplexing:

$x_{i,j}\&Element;\{0,1\},\&ForAll;i,\&ForAll;j$

4. every group of D2D is to Resource Block that can and can only a multiplexing phone user:

$\underset{j=1}{\overset{M}{\&Sigma;}}{x}_{i,j}=1,\&ForAll;i$

5. each phone user's Resource Block at most can only be by one group of D2D to multiplexing:

$\underset{i=1}{\overset{N_d}{\&Sigma;}}{x}_{i,j}\&le;1,\&ForAll;j$

6. D2D user's maximum transmission power limits:

$0\&le;p_{i,j}\&le;p_{max},\&ForAll;i,\&ForAll;j$

Every group of D2D centering comprises two D2D users, and one of them is for receiving user, and another is for sending user;

Wherein: N_dRepresent the right group number of D2D, M represents the number of allowable resource piece, and i represents i group D2D couple,J represents j Resource Block, and k represents the sequence number with the phone user of i group D2D to multiplexing same resource block; U_EETableShow the efficiency sum that all D2D are right;Represent that i group D2D is to multiplexingSpeed when j Resource Block; p_i,jRepresent that i group D2D is to the through-put power on j Resource Block, P_CRepresentThe power (not being subject to the impact of D2D on through-put power) that on mobile terminal, circuit consumes, w represents the bandwidth of Resource Block,h_D,iRepresent same group of D2D centering transmitting user and receive the channel gain between user, p_I,k,iRepresent and one group of D2DThe transmitting power of phone user to shared resource piece, h_k,iRepresent to share phone user and the D2D centering of same Resource BlockReception user between channel gain, σ²Represent the variance of white Gaussian noise;

(2) if x_i,jGet definite value, just removed D2D in former optimization problem between coupling, divide by object functionBecome two-layer independently optimization problem, wherein ground floor optimization problem is Power Control Problem, and second layer optimization problem is resourceAssignment problem;

(3), in ground floor optimization problem, every group of D2D is to the efficiency function U (p on fixed resource_i,j) be expressed as:

$U\left(p_{i,j}\right)=\frac{R\left(p_{i,j}\right)}{p_{i,j}+P_C}=\frac{w\&CenterDot;{\log }_2(1+\frac{p_{i,j}\&CenterDot;h_{D,i}}{p_{I,k,i}\&CenterDot;h_{k,i}+{\mathrm{\&sigma;}}^2})}{p_{i,j}+P_C},\&ForAll;i,\&ForAll;j---\left(2\right)$

This efficiency function has and successively decreases or first increase progressively the character of successively decreasing afterwards, and every group of D2D is to adopting separately advance and retreat method and goldSplit plot design is tried to achieve optimal solution separately;

(4) in second layer optimization problem, adopt heuristic resource allocation algorithm to carry out resource distribution, determine every group of D2DTo multiplexing resource.

In described step (4), the Mathematical Modeling of second layer optimization problem is:

$max\underset{i=1}{\overset{N_d}{\&Sigma;}}\underset{j=1}{\overset{M^{\&prime;}}{\&Sigma;}}{x}_{i,j}U\left(p_{i,j}^{*}\right)---\left(3\right)$

This Mathematical Modeling comprises following constraints:

$\underset{j=1}{\overset{M}{\&Sigma;}}{x}_{i,j}=1,\&ForAll;i$

$\underset{i=1}{\overset{N_d}{\&Sigma;}}{x}_{i,j}\&le;1,\&ForAll;j$

$x_{i,j}\&Element;\{0,1\},\&ForAll;i,\&ForAll;j$

Wherein:Represent the optimum efficiency value obtaining in ground floor optimization problem, the result of utilizing ground floor to optimizeAdopt heuristic resource allocation algorithm to carry out resource distribution, specifically comprise the steps:

4a). by every group of D2D to the efficiency U (p in each available resources_i,j) sort from big to small;

4b). first allow every group of D2D all take and can imitate U (p_i,j) maximum resource;

4c). find out resource and the D2D couple of conflict;

4d). resource and the D2D centering of conflict, calculate every group of D2D to adopting efficiency U (p_i,j) the resource institute of taking second placeThe efficiency loss causing, distributes to efficiency by the resource of conflict and loses maximum D2D couple, and all the other D2D are to multiplexing efficiencyThe resource of taking second place;

4e). repeat 4c)～4d), until D2D does not conflict to multiplexing resource.

The above is only the preferred embodiment of the present invention, is noted that for those skilled in the art, under the premise without departing from the principles of the invention, can also make some improvements and modifications, these improvements and modifications are alsoShould be considered as protection scope of the present invention.

Claims (2)

1. the high energy efficiency method for optimizing resources based on advance and retreat method and Fibonacci method, is characterized in that: comprise the steps:

(1) set up the object function of efficiency, suc as formula (1)

${\mathrm{maxU}}_{EE}=\underset{i=1}{\overset{N_d}{\&Sigma;}}\frac{\underset{j=1}{\overset{M}{\&Sigma;}}{x}_{i,j}\&CenterDot;R\left(p_{i,j}\right)}{\underset{j=1}{\overset{M}{\&Sigma;}}{x}_{i,j}\&CenterDot;p_{i,j}+P_C}---\left(1\right)$

This object function comprises following constraints:

1. every group of minimum transmission rate request that D2D is right, minimum transfer rate can not be less than γ_i, not D2D on the same groupRight minimum transfer rate is identical or different:

$R\left(p_{i,j}\right)\&GreaterEqual;{\mathrm{\&gamma;}}_i,\&ForAll;i,\&ForAll;j$

2. with one group of D2D to sharing the phone user of same resource block two D2D users' to this group D2D centeringJamming power must be less than certain value τ:

$p_{I,k,i}\&CenterDot;h_{k,i}\&le;\mathrm{\&tau;},\&ForAll;x_{i,j}=1$

③x_i,jGet 1 expression i group D2D multiplexing to selecting j Resource Block to carry out, x_i,jGet 0 expression i group D2DTo not selecting j Resource Block to carry out multiplexing:

$x_{i,j}\&Element;\{0,1\},\&ForAll;i,\&ForAll;j$

4. every group of D2D is to Resource Block that can and can only a multiplexing phone user:

$\underset{j=1}{\overset{M}{\&Sigma;}}{x}_{i,j}=1,\&ForAll;i$

5. each phone user's Resource Block at most can only be by one group of D2D to multiplexing:

$\underset{i=1}{\overset{N_d}{\&Sigma;}}{x}_{i,j}\&le;1,\&ForAll;j$

6. D2D user's maximum transmission power limits:

$0\&le;p_{i,j}\&le;p_{max},\&ForAll;i,\&ForAll;j$

Every group of D2D centering comprises two D2D users, and one of them is for receiving user, and another is for sending user;

Wherein: N_dRepresent the right group number of D2D, M represents the number of allowable resource piece, and i represents i group D2D couple,J represents j Resource Block, and k represents the sequence number with the phone user of i group D2D to multiplexing same resource block; U_EETableShow the efficiency sum that all D2D are right;Represent that i group D2D is to multiplexingSpeed when j Resource Block; p_i,jRepresent that i group D2D is to the through-put power on j Resource Block, P_CRepresentThe power that on mobile terminal, circuit consumes, w represents the bandwidth of Resource Block, h_D,iRepresent same group of D2D centering transmitting useChannel gain between family and reception user, p_I,k,iRepresent the transmitting with the phone user of one group of D2D to shared resource piecePower, h_k,iRepresent to share the channel gain between the phone user of same Resource Block and the reception user of D2D centering, σ²TableShow the variance of white Gaussian noise;

(2) if x_i,jGet definite value, just removed D2D in former optimization problem between coupling, divide by object functionBecome two-layer independently optimization problem, wherein ground floor optimization problem is Power Control Problem, and second layer optimization problem is resourceAssignment problem;

(3), in ground floor optimization problem, every group of D2D is to the efficiency function U (p on fixed resource_i,j) be expressed as:

$U\left(p_{i,j}\right)=\frac{R\left(p_{i,j}\right)}{p_{i,j}+P_C}=\frac{w\&CenterDot;{\log }_2\left(1+\frac{p_{i,j}\&CenterDot;h_{D,i}}{p_{I,k,i}\&CenterDot;h_{k,i}{\mathrm{\&sigma;}}^2}\right)}{p_{i,j}+P_C},\&ForAll;i,\&ForAll;j---\left(2\right)$

This efficiency function has and successively decreases or first increase progressively the character of successively decreasing afterwards, and every group of D2D is to adopting separately advance and retreat method and goldSplit plot design is tried to achieve optimal solution separately;

(4) in second layer optimization problem, adopt heuristic resource allocation algorithm to carry out resource distribution, determine every group of D2DTo multiplexing resource.

2. the high energy efficiency method for optimizing resources based on advance and retreat method and Fibonacci method according to claim 1, its spyLevy and be: in described step (4), the Mathematical Modeling of second layer optimization problem is:

$max\underset{i=1}{\overset{N_d}{\&Sigma;}}\underset{j=1}{\overset{M^{\&prime;}}{\&Sigma;}}{x}_{i,j}U\left(p_{i,j}^{*}\right)---\left(3\right)$

This Mathematical Modeling comprises following constraints:

$\underset{j=1}{\overset{M}{\&Sigma;}}{x}_{i,j}=1,\&ForAll;i$

$\underset{i=1}{\overset{N_d}{\&Sigma;}}{x}_{i,j}\&le;1,\&ForAll;j$

$x_{i,j}\&Element;\{0,1\},\&ForAll;i,\&ForAll;j$

Wherein:Represent the optimum efficiency value obtaining in ground floor optimization problem, the result of utilizing ground floor to optimizeAdopt heuristic resource allocation algorithm to carry out resource distribution, specifically comprise the steps:

4a). by every group of D2D to the efficiency U (p in each available resources_i,j) sort from big to small;

4b). first allow every group of D2D all take and can imitate U (p_i,j) maximum resource;

4c). find out resource and the D2D couple of conflict;

4d). resource and the D2D centering of conflict, calculate every group of D2D to adopting efficiency U (p_i,j) the resource institute of taking second placeThe efficiency loss causing, distributes to efficiency by the resource of conflict and loses maximum D2D couple, and all the other D2D are to multiplexing efficiencyThe resource of taking second place;

4e). repeat 4c)～4d), until D2D does not conflict to multiplexing resource.