CN102045753A - Centralized interference calculating method and device for orthogonal frequency division multiplexing network - Google Patents

Abstract

The invention provides a centralized interference calculating method and device for an orthogonal frequency division multiplexing (OFDM) network, belonging to interference methods and devices. The method comprises the following steps of: acquiring the channel measurement information, the transmitting power planned to be used and the target SINR (Signal to Interference plus Noise Ratio) of users served by each base station in a cell cluster of uplink business; and analyzing the transmitting power of the users according to the channel measurement information, the transmitting power planned to be used and the target SINR to obtain intracell interference to users. The invention increases the calculation accuracy of intracell interference and benefits increasing the multi-user diversity gain and the throughput of the system, so that the problems of low multi-user diversity gain and low throughput caused by inaccurate interference calculation in the prior art are solved.

Description

The centralized interference calculation method and the device that are used for OFDM networks

Technical field

The present invention relates to the communications field, in particular to a kind of centralized interference calculation method and device that is used for OFDM networks.

Background technology

In order to tackle the challenge of broadband access technology, simultaneously in order to satisfy novel business demand, the 3GPP of International Standards Organization (3rd Generation Partnership Project, third generation partner program) started the standardization effort of its Long Term Evolution (Long TermEvolution abbreviates LTE as) technology in the end of the year 2004.The LTE-Advanced working group meeting of holding in Shenzhen in April, 2008 has proposed objectives such as the following table to the LTE transmission system:

In order to reach like this high speed and the spectrum efficiency that LTE-Advanced requires, (the Signal Interference Noise Ratio of user's Signal to Interference plus Noise Ratio in the system, abbreviate SINR as) must be greatly improved, this just needs accurately predicting or control to disturb.Because the LTE system can guarantee between the user sub-district in well orthogonality, thereby has avoided interference (Inter-Cell Interference abbreviates ICI as) in the sub-district effectively.In OFDM (OrthogonalFrequency Division Multiplexing, OFDM) system, presence of intercell interference is to be produced by the user that other sub-districts take same sub-carrier, becomes the main interference source in the LTE system.Because interference source negligible amounts, equalization is insufficient, presence of intercell interference is non-albefaction in the OFDM network, so presence of intercell interference can produce fluctuation along with neighbor cell time-frequency domain scheduling, and there is big gap in the true SINR when this causes the SINR that estimates with scheduling.This error will significantly reduce the multi-user diversity gain that scheduling brings.

3GPP once proposed three class presence of intercell interference minimizing method, i.e. interference randomization, interference eliminated and interference coordinations.Interference randomization is meant a class technology of disturbing compacting by the randomize interference signal, as frequency hopping; Interference cancellation techniques is by utilize processing gain to disturb a class technology of compacting at user side, as interlacing multi-address; Interference coordination technique then is by in minizone reasonable distribution resource, makes used resource quadrature between neighbor cell as far as possible, thereby the interference of minizone is reduced, as soft-frequency reuse and partial frequency multiplexing.Defectives such as though these technology can alleviate the influence of ICI, it is responsive all to have a judgement, and it is higher to use complexity, and operability is relatively poor under the actual environment condition.

Therefore in the discussion of LTE-adv, centralized technology of uniting distribution based on many local resources has been proposed.The name of submitting to 3GPP in April, 2008 is called " CandidateEnabling Techniques for LTE-Advanced (candidate's Driving technique of LTE-A) " (motion number: point out in motion REV-080018), can carry out centralized scheduling by the application distribution antenna, promptly each base station all is distributed to the antenna website that a plurality of optical fiber connect in the sub-district.The sub-district be can obtain like this and gain and collaborative transmitting-receiving gain shunk.The name of submitting to 3GPP in April, 2008 is called " Consideration on Technical Candidates forIMT-Advanced (to the consideration of IMT-A candidate technologies) " (motion number: proposed multi-hop relay (Multi-hop Relaying) technology in motion REV-080019), be that center base station links to each other with IP network by wire link, telepoint base station then need pass through relay base station, and then inserts the Internet by center base station.All base stations all at first provide the user of coverage cell to insert; In addition, also provide the converging of telepoint base station business as relay base station, center base station then is responsible for the up-downgoing data dispatch of relaying and telepoint base station.The benefit of setting up relay base station is for can extended coverage range, improve throughput of system and open up novel business, also exist some shortcomings simultaneously, as strengthened system complexity, increase the spending of control signal or signaling, required a large amount of changes of current 3GPP LTE parameter in addition.

The inventor find to be used in the correlation technique OFDM network the centralized resources distribution method since presence of intercell interference calculate inaccurate, thereby cause multi-user diversity gain and throughput of system lower.

Summary of the invention

The present invention aims to provide a kind of centralized interference calculation method and device of the OFDM of being used for network, can solve the multi-user diversity gain and the lower problem of throughput of system that cause owing to interference calculation is inaccurate in the correlation technique.

To achieve these goals, according to an aspect of the present invention, a kind of centralized interference calculation method of the OFDM of being used for network is provided, has may further comprise the steps: obtain the user that each base station is served in the cell cluster of uplink service channel measurement information, intend the transmitting power and the target SINR that adopt; The transmitting power and the target SINR that adopt according to channel measurement information, plan analyze user's transmitting power, obtain the presence of intercell interference that the user is subjected to.

Preferably, in said method, root is analyzed user's transmitting power according to transmitting power and the target SINR that channel measurement information, plan adopt, obtaining the presence of intercell interference that the user is subjected to comprises: according to channel measurement information, the transmitting power and the target SINR that intend adopting user's transmitting power is carried out linear modelling, obtain first matrix equation; First matrix equation is carried out iterative, obtain the target transmit power of target SINR correspondence; Calculate the presence of intercell interference that the user is subjected to according to target transmit power.

Preferably, in said method, channel measurement information comprises: k travelling carriage is to h _lThe link gain of individual base station

Wherein, k=1,2 ... m, m are the number of users in the cell cluster, and m user corresponds respectively to m travelling carriage, l=1, and 2 ... m, and l travelling carriage belongs to h _lIndividual base station, h _l=1,2 ... n, n are the base station number in the cell cluster; L travelling carriage is to its affiliated base station h _lLink gain N the noise power η of base station in l travelling carriage frequency range _lM travelling carriage is to the occupied information of Resource Block.

Preferably, in said method, user's transmitting power is analyzed, obtained the presence of intercell interference that the user is subjected to and comprise according to channel measurement information, the transmitting power and the target SINR that intend to adopt: according to

η _l, occupied information and target

Transmitting power to the user is carried out linear modelling, obtains the first matrix equation P ^(m)=BP ^(m-1)+ F, wherein, B is that m * m maintains matrix number, the capable k column element of the l of B b _LkFor:

Wherein

P and F are m dimensional vector, P=[P ₁, P ₂..., P _m] ^T, F=[f ₁, f ₂..., f _m] ^T, wherein

The transmitting power that adopts according to m user's plan is expressed as vector form P ⁽⁰⁾According to P ⁽⁰⁾To P ^(m)=BP ^(m-1)+ F carries out iterative, obtains the target transmit power of target SINR correspondence; Calculate the presence of intercell interference that the user is subjected to according to target transmit power.

To achieve these goals, according to an aspect of the present invention, a kind of centralized interference calculation method of the OFDM of being used for network is provided, has may further comprise the steps: the channel measurement information, the initial interference power that receives and the target SINR that obtain the user that each base station is served in the cell cluster of downlink business; According to channel measurement information, initial interference power and target SINR, calculate the presence of intercell interference that the user is subjected to.

Preferably, in said method, according to channel measurement information, initial interference power and target SINR, calculating the presence of intercell interference that the user is subjected to comprises: according to channel measurement information, initial interference power and target SINR the interference power that the user receives is carried out linear modelling, obtain second matrix equation; Second matrix equation is carried out iterative, obtain the presence of intercell interference that the user is subjected to.

Preferably, in said method, channel measurement information comprises: k travelling carriage is to h _jThe link gain of individual base station

Wherein, k=1,2 ... m, m are the number of users in the cell cluster, and m user corresponds respectively to m travelling carriage, j=1, and 2 ... m, and j travelling carriage belongs to h _jIndividual base station, h _j=1,2 ... n, n are the base station number in the cell cluster; J travelling carriage is to its affiliated base station h _jLink gain

N the noise power η of base station in k travelling carriage frequency range _kM travelling carriage is to the occupied information of Resource Block.

Preferably, in said method,, calculate the presence of intercell interference that the user is subjected to and comprise according to channel measurement information, initial interference power and target SINR: according to

η _k, occupied information and target The interference power that the user receives is carried out linear modelling, obtain the second matrix equation I ^(m)=TI ^(m-1)+ E, wherein, T is that m * m maintains matrix number, the capable j column element of the k of T t _KjFor:

Wherein

I and E are m dimensional vector, I=[I ₁, I ₂..., I _m] ^T, E=[η ₁, η ₂..., η _m] ^TInitial interference power according to m user is expressed as vector form I ⁽⁰⁾According to I ⁽⁰⁾To I ^(m)=TI ^(m-1)+ E carries out iterative, obtains the presence of intercell interference that the user is subjected to.

To achieve these goals, according to an aspect of the present invention, a kind of centralized interference calculation device of the OFDM of being used for network is provided, comprise: first acquisition module, be used to obtain the user that each base station is served in the cell cluster of uplink service channel measurement information, intend the transmitting power and the target SINR that adopt; Analysis module is used for according to transmitting power and target SINR that channel measurement information, plan adopt user's transmitting power being analyzed, and obtains the presence of intercell interference that the user is subjected to.

To achieve these goals, according to an aspect of the present invention, a kind of centralized interference calculation device of the OFDM of being used for network is provided, comprise: second acquisition module is used to obtain the user's that each base station is served in the cell cluster of downlink business channel measurement information, the initial interference power that receives and target SINR; Computing module is used for calculating the presence of intercell interference that the user is subjected to according to channel measurement information, initial interference power and target SINR.

Parameters such as interference power, transmitting power, target SINR have been considered in the process that the foregoing description disturbs between calculation plot, so improved the computational accuracy of presence of intercell interference, help improving the multi-user diversity gain and the throughput of system of system, so overcome multi-user diversity gain and the lower problem of throughput of system that causes owing to interference calculation is inaccurate in the correlation technique.

Description of drawings

Accompanying drawing described herein is used to provide further understanding of the present invention, constitutes the application's a part, and illustrative examples of the present invention and explanation thereof are used to explain the present invention, do not constitute improper qualification of the present invention.In the accompanying drawings:

Fig. 1 shows the flow chart according to the interference calculation method of first embodiment of the invention;

Fig. 2 shows the schematic diagram according to the cell cluster of second embodiment of the invention;

Fig. 3 shows the flow chart according to the interference calculation method of third embodiment of the invention;

Fig. 4 shows the schematic diagram of communicating by letter in the cell cluster according to the interference calculation method of fourth embodiment of the invention;

Fig. 5 shows the flow chart according to the interference calculation method of fifth embodiment of the invention;

Fig. 6 shows the structure chart according to the interference calculation device of sixth embodiment of the invention;

Fig. 7 shows the structure chart according to the interference calculation device of seventh embodiment of the invention.

Embodiment

Below with reference to the accompanying drawings and in conjunction with the embodiments, describe the present invention in detail.

Fig. 1 shows the flow chart according to the interference calculation method of first embodiment of the invention, and this method may further comprise the steps:

Step 101, obtain the user that each base station is served in the cell cluster of uplink service channel measurement information, intend the transmitting power and the target SINR that adopt;

Step 102, the transmitting power and the target SINR that adopt according to channel measurement information, plan analyze user's transmitting power, obtain the presence of intercell interference that the user is subjected to.

Present embodiment is the situation of uplink service, at first obtain this moment the user that each base station is served in the cell cluster of uplink service channel measurement information, intend the transmitting power and the target SINR that adopt, according to the above-mentioned information of obtaining the transmitting power of user in the cell cluster is analyzed then, thereby calculated the presence of intercell interference that the user is subjected to.Owing to considered parameters such as interference power, transmitting power, target SINR in the process of between calculation plot, disturbing, so improved the computational accuracy of presence of intercell interference, help improving the multi-user diversity gain and the throughput of system of system, so overcome multi-user diversity gain and the lower problem of throughput of system that causes owing to interference calculation is inaccurate in the correlation technique.

The interference calculation method of present embodiment is the discontinuity at the scheduling of OFDM minizone, on basis, propose based on many cell set Chinese style scheduling scheme, this method is based on the cell cluster notion, the geographic area that several base stations that cell cluster is meant and covers in the OFDM network continuously, quality is relevant are formed comprises 7～19 websites (can according to circumstances determine desirable every cell cluster website quantity) usually.The actual size of cell cluster is distinguished to some extent with the different communication environment, needs to consider geographic separation, base station density, user distribution, factors such as data processing and analysis tool.Each cell cluster is provided with a bunch of head.Fig. 2 shows the schematic diagram according to the cell cluster of second embodiment of the invention, and the cell cluster among Fig. 2 is made up of 7 sub-districts, and a bunch position as shown in the figure.

Preferably, in said method, step 102 comprises: the transmitting power and the target SINR that adopt according to channel measurement information, plan carry out linear modelling to user's transmitting power, obtain first matrix equation; First matrix equation is carried out iterative, obtain the target transmit power of target SINR correspondence; Calculate the presence of intercell interference that the user is subjected to according to target transmit power.

Present embodiment adopts the method for linear network modeling to carry out presence of intercell interference and calculates, and each excited users in the network is described with a linear equation, form a system of linear equations, and available alternative manner is found the solution.Do like this, in the multi-user diversity gain that improves system, estimated presence of intercell interference effectively, improved throughput.Owing to comprised parameters such as transmitting power, target SINR in the equation group, be a more accurate model; The account form of its iterative computation is accurate, is easy to use computer realization.

Preferably, in said method, channel measurement information comprises: k travelling carriage is to h _lThe link gain of individual base station Wherein, k=1,2 ... m, m are the number of users in the cell cluster, and m user corresponds respectively to m travelling carriage, l=1, and 2 ... m, and l travelling carriage belongs to h _lIndividual base station, h _l=1,2 ... n, n are the base station number in the cell cluster; L travelling carriage is to its affiliated base station h _lLink gain

N the noise power η of base station in l travelling carriage frequency range _lM travelling carriage is to the occupied information of Resource Block.

The Node-B that is positioned at bunch head in the present embodiment is by the communication between cell cluster Node-B, and each Node-B institute service-user arrives the channel measurement information between each Node-B in obtaining bunch, comprises

η _l, each travelling carriage is to the occupied information of Resource Block and path loss etc.Present embodiment has obtained the current channel measurement information of each user in the cell cluster, thereby has helped to improve the accuracy that presence of intercell interference is calculated.

Preferably, in said method, step 102 comprises: according to

η _l, occupied information v _LkWith target SINR γ _lTransmitting power to the user is carried out linear modelling, obtains first matrix equation:

P ^(m)＝BP ^(m-1)+F， (1)

Wherein, B is that m * m maintains matrix number, the capable k column element of the l of B b _LkFor:

$b_{\mathrm{lk}}=\left\{\begin{array}{cc}\frac{{\mathrm{\γ}}_l}{g_{h_{l}l}}{v}_{\mathrm{lk}}{g}_{h_{l}k},& k\≠l\\ 0,& k=l\end{array}\right.,---\left(2\right)$

Wherein, v _LkFor:

And P is the m dimensional vector, P=[P ₁, P ₂..., P _m] ^T, F is a m dimension constant vector, F=[f ₁, f ₂..., f _m] ^T, wherein

The transmitting power that adopts according to m user's plan is expressed as vector form P ⁽⁰⁾According to P ⁽⁰⁾To P ^(m)=BP ^(m-1)+ F carries out iterative, obtains the target transmit power of target SINR correspondence; Calculate the presence of intercell interference that the user is subjected to according to target transmit power.

Present embodiment is basis at first

η _l, v _LkWith γ _lObtain the first matrix equation P ^(m)=BP ^(m-1)The coefficient matrix B of+F and constant vector F bring B and F in first matrix equation into then, the equivalent vector form P of the transmitting power that adopts with m user's plan ⁽⁰⁾Iteration starting point as first matrix equation, it is carried out iterative, thereby obtain the target transmit power of target SINR correspondence, promptly be suitable for the optimal user transmitting power of current wireless environment, the conversion relation according to transmitting power and interference power obtains the presence of intercell interference that the user is subjected at last.Present embodiment is obtaining

η _l, v _Lk, γ _lIntend adopting parameter such as transmitting power with the user after, can directly bring equation into, and adopt the method for iterative computation to find the solution, be easy to use computer realization, thus not only easy but also improved computational accuracy.

Preferably, in said method, after step 102, also comprise: carry out inter-cell united resource allocation according to described presence of intercell interference.

Present embodiment carries out inter-cell united resource allocation according to these presence of intercell interference data again after calculating presence of intercell interference.Do like this, effectively utilized the result of calculation of presence of intercell interference, improved the multi-user diversity gain and the throughput of system of system.

Fig. 3 shows the flow chart according to the interference calculation method of third embodiment of the invention, and present embodiment is a upstream case, and this method may further comprise the steps:

Step 301, the Node-B that is positioned at bunch head is by the communication between cell cluster Node-B, in obtaining bunch under each Node-B service-user to the channel measurement metrical informations such as path loss between each Node-B, transmitting power that the user intends adopting (because present embodiment is a uplink service) and up target SINR information etc.;

Step 302, the service eNode-B that is positioned at bunch head is according to bunch other eNode-B feedacks, disturbance regime in the network is carried out linear modelling, each excited users in the cell cluster is described with a linear equation, the equation of m excited users is formed a system of linear equations, has comprised parameters such as path loss, transmitting power, target SINR in the equation group;

Step 303, utilize computer to carry out iterative: the method by iteration is found the solution first matrix equation, acquisition is suitable for the user emission power of current wireless environment and suffered interference power, and further analysis can obtain Modulation and Coding Scheme grade, relevant informations such as code rate.

Linear modelling in the step 302 comprises following substep again:

Step 3021, the system of setting up departments has n base station, and m travelling carriage for up link, has

$I_l=\underset{\underset{k\≠l}{k=1}}{\overset{m}{\mathrm{\Σ}}}{v}_{\mathrm{lk}}{g}_{h_{l}k}{P}_k+{\mathrm{\η}}_l,---\left(4\right)$

Wherein, l travelling carriage belongs to h _lIndividual base station, the set { h of all base stations ₁, h ₂... h _m∈ 1,2 ... and n}, because this bunch sub-district is a centralized distribution pattern, so this information is to concentrate distributor known (in the step 301).I _lBe base station h _lThe interference power that in l travelling carriage frequency range, receives, P _kBe the transmitting power of k travelling carriage,

Be that k travelling carriage is to h _lThe link gain of individual base station, η _lBe the noise power of base station in l travelling carriage frequency range, v _LkShown in above-mentioned (3) formula;

Step 3022, calculate transmitting power according to target SINR: the upstream sinr desired value of establishing l travelling carriage is γ _l, then have

$P_l=\frac{I_l{\mathrm{\γ}}_l}{g_{h_{l}l}},---\left(5\right)$

P wherein _lIt is the transmitting power of l travelling carriage;

Step 3023, according to bunch in each sub-district feedack, be predicted as and reach the required transmitting power of target SINR: bringing (4) formula into (5) formula can release:

$P_l=\frac{{\mathrm{\γ}}_l}{g_{h_{l}l}}(\underset{\underset{k\≠l}{k=1}}{\overset{m}{\mathrm{\Σ}}}{v}_{\mathrm{lk}}{g}_{h_{l}k}{P}_k+{\mathrm{\η}}_l);---\left(6\right)$

Step 3024 because l user chooses wantonly, therefore for each user, can provide the equation of similar (6) formula, and m user is corresponding to m equation, and m equation formed a system of linear equations, write as matrix form and is exactly

P＝BP+F； (7)

Wherein, P and F all are m dimensional vectors, are respectively P=[P ₁, P ₂..., P _m] ^T, F=[f ₁, f ₂..., f _m] ^T, f wherein _lFor

B is that m * m maintains matrix number, the capable k column element of its l b _LkShown in above-mentioned (2) formula; (7) iteration form of formula is:

P ^(m)＝BP ^(m-1)+F； (8)

(8) formula is first matrix equation that is used for iterative.

Present embodiment has solved each user's transmitting power by above step, and further analysis can obtain relevant informations such as presence of intercell interference that the user is subjected to, Modulation and Coding Scheme grade, code rate.System can dispatch system resource in view of the above.

For up matrix equation P=BP+F, can be write as (E-B) P=F, i.e. CP=F, C=E-B wherein, E is a unit matrix, and C is strict diagonally dominant matrix, this equation has stable solution, now proves as follows.

The element of C is a random number in real system, when proving convergence, gets its statistical value.

Proof: establish the 1st row of Matrix C, the element of k row is c _Lk, then have

$\underset{\underset{k\≠l}{k=1}}{\overset{m}{\mathrm{\Σ}}}\left|c_{\mathrm{lk}}\right|=\underset{\underset{k\≠l}{k=1}}{\overset{m}{\mathrm{\Σ}}}|-b_{\mathrm{lk}}|=\underset{\underset{k\≠l}{k=1}}{\overset{m}{\mathrm{\Σ}}}|-\frac{{\mathrm{\γ}}_l}{g_{h_{l}l}}{v}_{\mathrm{lk}}{g}_{h_{l}k}|,---\left(9\right)$

(9) in the formula, γ _l,

Separate, suppose A (γ _k)=γ is (promptly to γ _kBe averaged), this γ can think the Signal to Interference plus Noise Ratio that all user's uniform distribution power of each base station obtain, and then has

$\mathrm{\&gamma;}=A\left(\frac{\frac{P_{h_{l}l}}{g_{h_{l}l}}}{\underset{\underset{k\&NotEqual;l}{k=1}}{\overset{m}{\mathrm{\&Sigma;}}}{v}_{\mathrm{kl}}\frac{P_{h_{k}k}}{g_{h_{k}l}}+\mathrm{\&eta;}}\right)\&DoubleRightArrow;\mathrm{\&gamma;}<A\left(\frac{\frac{P_{h_{l}l}}{g_{h_{l}l}}}{\underset{\underset{k\&NotEqual;l}{k=1}}{\overset{m}{\mathrm{\&Sigma;}}}{v}_{\mathrm{kl}}\frac{P_{h_{k}k}}{g_{h_{k}l}}}\right)\&DoubleRightArrow;\mathrm{\&gamma;}\&CenterDot;A\left(\underset{\underset{k\&NotEqual;l}{k=1}}{\overset{m}{\mathrm{\&Sigma;}}}{v}_{\mathrm{kl}}\frac{P_{h_{k}k}}{g_{h_{k}l}}\right)<A\left(\frac{P_{h_{l}l}}{g_{h_{l}l}}\right),---\left(10\right)$

Because the transmitted power of each travelling carriage is equal,

Can get

$1>A\left(\underset{\underset{k\&NotEqual;l}{k=1}}{\overset{m}{\mathrm{\&Sigma;}}}\frac{{\mathrm{\&gamma;}}_l}{g_{h_{l}l}}{v}_{\mathrm{lk}}{g}_{h_{l}k}\right),---\left(11\right)$

And | c _Ll|=1, therefore can get

$A\left(\right|c_{\mathrm{ii}}\left|\right)>\left(\underset{\underset{j\&NotEqual;i}{j=1}}{\overset{n}{\mathrm{\&Sigma;}}}\right|c_{\mathrm{ij}}\left|\right),---\left(12\right)$

Therefore the C matrix is strict diagonally dominant matrix, when C is diagonally dominant matrix, for initial vector P arbitrarily ⁽⁰⁾, the Jucobi iterative method of formula CP=F can converge to stable solution.Formula P ^(m)=BP ^(m-1)+ F is the Jacobi iteration form of CP=F, that is to say, for initial vector P arbitrarily ⁽⁰⁾, formula P ^(m)=BP ^(m-1)+ F convergence.

Proof finishes.

Fig. 4 shows the schematic diagram of communicating by letter in the cell cluster according to the interference calculation method of fourth embodiment of the invention, and the method for present embodiment may further comprise the steps:

Step 1 as shown in Figure 4, is formed a cell cluster by 7 sub-districts, and the Node-B at cell cluster center is a bunch Node-B of this sub-district.A bunch Node-B can by bunch in Node-B between communication obtain bunch in other base stations information such as path loss G, transmitting power P, target SINR of the user (as MS1, MS2, MS3) of service down; Overstriking font representation numerical matrixs such as path loss G, transmitting power P, target SINR herein comprise the information such as path loss, transmitting power, target SINR of each user in the cell cluster respectively in the matrix;

Step 2, information such as path loss G, the transmitting power P that the Node-B of bunch head feeds back according to other Node-B in the cell cluster, target SINR are calculated interference level I and other system performance information in the cell cluster under this situation;

Step 3 according to the interference level I of step 2 acquisition and the target SINR of system, is calculated the parameters such as transmitting power P ' that the user desires to reach the required employing of this target SINR value.Obtainable in the hope of obtaining under this interference (I) situation near the transmitting power of target SINR;

Step 4, the Node-B that is positioned at bunch head calculates the interference I ' of (path loss is G) under this environment according to the new transmitting power P ' that calculates, i.e. execution in step two once more.After obtaining new interference I ',, calculate transmitting power P required under this situation according to aims of systems SINR ", i.e. execution in step three once more.Thereby obtain new interference I ' and the transmitting power P of a cover ", P herein " and I ' isoparametric formulations obtain as calculated, be different from the numerical matrix of P ' and I;

Step 5: the Node-B that is positioned at bunch head carries out rapid two processes to step 4 repeatedly, promptly carries out interative computation by computer, obtains optimum parameters such as user emission power.And the parameters such as user emission power that computing is tried to achieve are returned to other Node-B in the cell cluster.

Present embodiment adopts the linear modelling method of inter-cell united resource allocation on centralized scheduled basis, with system of linear equations ofdm system is carried out modeling, and available alternative manner is found the solution.This method can be estimated presence of intercell interference effectively in the multi-user diversity gain that improves system, improve throughput; And the account form of its iterative computation is accurate, is easy to use computer realization.

Fig. 5 shows the flow chart according to the interference calculation method of fifth embodiment of the invention, and this method may further comprise the steps:

Step 501 is obtained the user's that each base station is served in the cell cluster of downlink business channel measurement information, the initial interference power that receives and target SINR;

Step 502 according to channel measurement information, initial interference power and target SINR, calculates the presence of intercell interference that the user is subjected to.

Present embodiment is the situation of downlink business, at first obtain the user's that each base station is served in the cell cluster of downlink business channel measurement information, the initial interference power that receives and target SINR this moment, obtains the presence of intercell interference that the user is subjected to according to the above-mentioned information calculations of obtaining then.Owing to considered parameters such as interference power, target SINR in the process of between calculation plot, disturbing, so improved the computational accuracy of presence of intercell interference, help improving the multi-user diversity gain and the throughput of system of system, so overcome multi-user diversity gain and the lower problem of throughput of system that causes owing to interference calculation is inaccurate in the correlation technique.

Preferably, in said method, step 502 comprises: according to channel measurement information, initial interference power and target SINR the interference power that the user receives is carried out linear modelling, obtain second matrix equation; Second matrix equation is carried out iterative, obtain the presence of intercell interference that the user is subjected to.

Present embodiment adopts the method for linear network modeling to carry out presence of intercell interference and calculates, and each excited users in the network is described with a linear equation, form a system of linear equations, and available alternative manner is found the solution.Do like this, in the multi-user diversity gain that improves system, estimated presence of intercell interference effectively, improved throughput.Owing to comprised parameters such as interference power, target SINR in the equation group, be a more accurate model; The account form of its iterative computation is accurate, is easy to use computer realization.

Preferably, in said method, channel measurement information comprises: k travelling carriage is to h _jThe link gain of individual base station

Wherein, k=1,2 ... m, m are the number of users in the cell cluster, and m user corresponds respectively to m travelling carriage, j=1, and 2 ... m, and j travelling carriage belongs to h _jIndividual base station, h _j=1,2 ... n, n are the base station number in the cell cluster; J travelling carriage is to its affiliated base station h _jLink gain

N the noise power η of base station in k travelling carriage frequency range _kM travelling carriage is to the occupied information of Resource Block.

The Node-B that is positioned at bunch head in the present embodiment is by the communication between cell cluster Node-B, and each Node-B institute service-user arrives the channel measurement information between each Node-B in obtaining bunch, comprises

η _k, each travelling carriage is to the occupied information of Resource Block and path loss etc.Present embodiment has obtained the current channel measurement information of each user in the cell cluster, thereby has helped to improve the accuracy that presence of intercell interference is calculated.

Preferably, in said method, step 502 comprises: according to

η _k, occupied information v _KjWith target SINR γ _jThe interference power that the user receives is carried out linear modelling, obtains second matrix equation:

I ^(m)＝TI ^(m-1)+E， (13)

Wherein, T is that m * m maintains matrix number, the capable j column element of the k of T t _KjFor:

$t_{\mathrm{kj}}=\left\{\begin{array}{cc}\frac{v_{\mathrm{kj}}{\mathrm{\&gamma;}}_j{g}_{h_{j}k}}{g_{h_{j}j}}& j\&NotEqual;k\\ 0,& j=k\end{array}\right.,---\left(14\right)$

Wherein, v _KjFor:

And I is the m dimensional vector, I=[I ₁, I ₂..., I _m] ^T, E is a m dimension constant vector, E=[η ₁, η ₂..., η _m] ^TInitial interference power according to m user is expressed as vector form I ⁽⁰⁾According to I ⁽⁰⁾To I ^(m)=TI ^(m-1)+ E carries out iterative, obtains the presence of intercell interference that the user is subjected to.

Present embodiment is basis at first

η _k, v _KjWith γ _jObtain the second matrix equation I ^(m)=TI ^(m-1)The coefficient matrix T of+E and constant vector E bring T and E in second matrix equation into then, with the equivalent vector form I of m user's initial interference power ⁽⁰⁾As the iteration starting point of second matrix equation, it is carried out iterative, thereby obtain the presence of intercell interference that the user is subjected to.Present embodiment is obtaining

η _l, v _Lk, γ _lAfter user's parameters such as initial interference power, can directly bring equation into, and adopt the method for iterative computation to find the solution, be easy to use computer realization, thus not only easy but also improved computational accuracy.

Preferably, in said method, after step 502, also comprise: carry out inter-cell united resource allocation according to described presence of intercell interference.

Present embodiment carries out inter-cell united resource allocation according to these presence of intercell interference data again after calculating presence of intercell interference.Do like this, effectively utilized the result of calculation of presence of intercell interference, improved the multi-user diversity gain and the throughput of system of system.

Down link linear modelling process and up link are similar, may further comprise the steps:

At first, the signal to noise ratio according to the user obtains

$P_{h_{k}k}=\frac{{\mathrm{\&gamma;}}_k{I}_k}{g_{h_{k}k}},---\left(16\right)$

Wherein, k represents k travelling carriage, is under the jurisdiction of h _kIndividual base station,

Be base station h _kTo the transmitting power of k travelling carriage, γ _kBe the descending SINR desired value of travelling carriage k,

Expression user k is to affiliated base station h _kChannel response.If the Background Noise Power of travelling carriage k is η _k, the interference I that is subjected to of down link travelling carriage k then _kFor:

$I_k=\underset{\underset{j\&NotEqual;k}{j=1}}{\overset{m}{\mathrm{\&Sigma;}}}{v}_{\mathrm{kj}}{P}_{h_{j}j}{g}_{h_{j}k}+{\mathrm{\&eta;}}_k,---\left(17\right)$

Wherein, v _KjIt is identical with up calculating,

Be base station h under j the user _jTo j user's transmitted power,

Expression user k is to the channel response of j user's affiliated base station hj;

(17) formula is further put in order, signal to noise ratio formula (i.e. (16) formula) substitution is got:

$I_k=\underset{\underset{j\&NotEqual;k}{j=1}}{\overset{m}{\mathrm{\&Sigma;}}}{I}_j\frac{v_{\mathrm{kj}}{\mathrm{\&gamma;}}_j{g}_{h_{j}k}}{g_{h_{j}j}}+{\mathrm{\&eta;}}_k,---\left(18\right)$

Because user k is for optional, therefore the interference that each user has corresponding reception to disturb can be shown as matrix form with this m user's interference table:

I＝TI+E， (19)

Wherein, I and E are the m dimensional vectors, are respectively I=[I ₁, I ₂..., I _m] ^T, E=[η ₁, η ₂..., η _m] ^T, T is that m * m maintains matrix number, wherein the element t of the capable j row of k _KjShown in above-mentioned (14) formula; (19) iteration form of formula is:

I ^(m)＝TI ^(m-1)+E， (20)

(20) formula is first matrix equation that is used for iterative;

The interference power I that receives according to the travelling carriage k that calculates _k, require γ in conjunction with the signal to noise ratio of travelling carriage _kAnd channel response Can calculate the transmitting power of its demand according to (16) formula.

Thus, all user's in sub-district transmitting power in this bunch, disturb and all calculate clearly.

By stable solution being arranged with the also provable descending matrix equation I=TI+E of up similar method of proof.

Fig. 6 shows the structure chart according to the interference calculation device of sixth embodiment of the invention, and this device comprises:

First acquisition module 601, be used to obtain the user that each base station is served in the cell cluster of uplink service channel measurement information, intend the transmitting power and the target SINR that adopt;

Analysis module 602 is used for according to transmitting power and target SINR that channel measurement information, plan adopt user's transmitting power being analyzed, and obtains the presence of intercell interference that the user is subjected to.

Present embodiment is the situation of uplink service, the user's that interior each base station of cell cluster of at first adopting this moment first acquisition module 601 to obtain uplink service is served channel measurement information, transmitting power and the target SINR that plan adopts, adopt analysis module 602 transmitting power of user in the cell cluster to be analyzed then, thereby calculate the presence of intercell interference that the user is subjected to according to the above-mentioned information of obtaining.Owing to considered parameters such as interference power, transmitting power, target SINR in the process of between calculation plot, disturbing, so improved the computational accuracy of presence of intercell interference, help improving the multi-user diversity gain and the throughput of system of system, so overcome multi-user diversity gain and the lower problem of throughput of system that causes owing to interference calculation is inaccurate in the correlation technique.

Preferably, said apparatus also comprises: first resource distribution module is used for carrying out inter-cell united resource allocation according to described presence of intercell interference.

Present embodiment also adopts first resource distribution module to carry out inter-cell united resource allocation according to these presence of intercell interference data.Do like this, effectively utilized the result of calculation of presence of intercell interference, improved the multi-user diversity gain and the throughput of system of system.

Fig. 7 shows the structure chart according to the interference calculation device of seventh embodiment of the invention, and this device comprises:

Second acquisition module 701 is used to obtain the user's that each base station is served in the cell cluster of downlink business channel measurement information, the initial interference power that receives and target SINR;

Computing module 702 is used for calculating the presence of intercell interference that the user is subjected to according to channel measurement information, initial interference power and target SINR.

Present embodiment is the situation of downlink business, the user's that interior each base station of cell cluster of at first adopting this moment second acquisition module 701 to obtain downlink business is served channel measurement information, the initial interference power that receives and target SINR adopt computing module 702 to obtain the presence of intercell interference that the user is subjected to according to the above-mentioned information calculations of obtaining then.Owing to considered parameters such as interference power, target SINR in the process of between calculation plot, disturbing, so improved the computational accuracy of presence of intercell interference, help improving the multi-user diversity gain and the throughput of system of system, so overcome multi-user diversity gain and the lower problem of throughput of system that causes owing to interference calculation is inaccurate in the correlation technique.

Preferably, said apparatus also comprises: second resource distribution module is used for carrying out inter-cell united resource allocation according to described presence of intercell interference.

Present embodiment also adopts second resource distribution module to carry out inter-cell united resource allocation according to these presence of intercell interference data.Do like this, effectively utilized the result of calculation of presence of intercell interference, improved the multi-user diversity gain and the throughput of system of system.

As can be seen from the above description, the above embodiments of the present invention have improved the computational accuracy of presence of intercell interference, help improving the multi-user diversity gain and the throughput of system of system.

Obviously, those skilled in the art should be understood that, above-mentioned each module of the present invention or each step can realize with the general calculation device, they can concentrate on the single calculation element, perhaps be distributed on the network that a plurality of calculation element forms, alternatively, they can be realized with the executable program code of calculation element, thereby, they can be stored in the storage device and carry out by calculation element, perhaps they are made into each integrated circuit modules respectively, perhaps a plurality of modules in them or step are made into the single integrated circuit module and realize.Like this, the present invention is not restricted to any specific hardware and software combination.

The above is the preferred embodiments of the present invention only, is not limited to the present invention, and for a person skilled in the art, the present invention can have various changes and variation.Within the spirit and principles in the present invention all, any modification of being done, be equal to replacement, improvement etc., all should be included within protection scope of the present invention.

Claims (10)

1. a centralized interference calculation method that is used for OFDM networks is characterized in that, may further comprise the steps:

Obtain the user's that each base station is served in the cell cluster of uplink service channel measurement information, transmitting power and the target Signal to Interference plus Noise Ratio that described user intends adopting;

According to transmitting power and described target Signal to Interference plus Noise Ratio that described channel measurement information, described plan adopt described user's transmitting power is analyzed, obtained the presence of intercell interference that described user is subjected to.

2. method according to claim 1, it is characterized in that, according to transmitting power and described target Signal to Interference plus Noise Ratio that described channel measurement information, described plan adopt described user's transmitting power is analyzed, obtaining the presence of intercell interference that described user is subjected to comprises: the transmitting power and the described target Signal to Interference plus Noise Ratio that adopt according to described channel measurement information, described plan carry out linear modelling to described user's transmitting power, obtain first matrix equation;

Described first matrix equation is carried out iterative, obtain the target transmit power of described target Signal to Interference plus Noise Ratio correspondence;

Calculate the presence of intercell interference that described user is subjected to according to described target transmit power.

3. method according to claim 1 is characterized in that, described channel measurement information comprises:

K travelling carriage is to h _lThe link gain of individual base station

Wherein, k=1,2 ... m, m are the number of users in the described cell cluster, and a described m user corresponds respectively to m travelling carriage, l=1, and 2 ... m, and l travelling carriage belongs to h _lIndividual base station, h _l=1,2 ... n, n are the base station number in the described cell cluster;

L travelling carriage is to its affiliated base station h _lLink gain

The noise power η of a described n base station in l travelling carriage frequency range _l

A described m travelling carriage is to the occupied information of Resource Block.

4. method according to claim 3, it is characterized in that, according to transmitting power and described target Signal to Interference plus Noise Ratio that described channel measurement information, described plan adopt described user's transmitting power is analyzed, is obtained the presence of intercell interference that described user is subjected to and comprise:

According to η _l, described occupied information and described target Signal to Interference plus Noise Ratio γ _lTransmitting power to described user is carried out linear modelling, obtains first matrix equation

P ^(m)＝BP ^(m-1)+F，

Wherein, B is that m * m maintains matrix number, the capable k column element of the l of B b _LkFor:

$b_{\mathrm{lk}}=\left\{\begin{array}{cc}\frac{{\mathrm{\&gamma;}}_l}{g_{h_{l}l}}{v}_{\mathrm{lk}}{g}_{h_{l}k},& k\&NotEqual;l\\ 0,& k=l\end{array}\right.,$ Wherein

P and F are m dimensional vector, P=[P ₁, P ₂..., P _m] ^T, F=[f ₁, f ₂..., f _m] ^T, wherein

The transmitting power that adopts according to a described m user's plan is expressed as vector form P ⁽⁰⁾

According to P ⁽⁰⁾To P ^(m)=BP ^(m-1)+ F carries out iterative, obtains the target transmit power of described target Signal to Interference plus Noise Ratio correspondence;

Calculate the presence of intercell interference that described user is subjected to according to described target transmit power.

5. a centralized interference calculation method that is used for OFDM networks is characterized in that, may further comprise the steps:

Obtain the user's that each base station is served in the cell cluster of downlink business channel measurement information, the initial interference power that receives and target Signal to Interference plus Noise Ratio;

According to described channel measurement information, described initial interference power and described target Signal to Interference plus Noise Ratio, calculate the presence of intercell interference that described user is subjected to.

6. method according to claim 5 is characterized in that, according to described channel measurement information, described initial interference power and described target Signal to Interference plus Noise Ratio, calculates the presence of intercell interference that described user is subjected to and comprises:

According to described channel measurement information, described initial interference power and described target Signal to Interference plus Noise Ratio the interference power that described user receives is carried out linear modelling, obtain second matrix equation;

Described second matrix equation is carried out iterative, obtain the presence of intercell interference that described user is subjected to.

7. method according to claim 5 is characterized in that, described channel measurement information comprises:

K travelling carriage is to h _jThe link gain of individual base station Wherein, k=1,2 ... m, m are the number of users in the described cell cluster, and a described m user corresponds respectively to m travelling carriage, j=1, and 2 ... m, and j travelling carriage belongs to h _jIndividual base station, h _j=1,2 ... n, n are the base station number in the described cell cluster;

J travelling carriage is to its affiliated base station h _jLink gain

The noise power η of a described n base station in k travelling carriage frequency range _k

A described m travelling carriage is to the occupied information of Resource Block.

8. method according to claim 7 is characterized in that, according to described channel measurement information, described initial interference power and described target Signal to Interference plus Noise Ratio, calculates the presence of intercell interference that described user is subjected to and comprises:

According to

η _k, described occupied information and described target Signal to Interference plus Noise Ratio γ _jThe interference power that described user receives is carried out linear modelling, obtain second matrix equation

I ^(m)＝TI ^(m-1)+E，

Wherein, T is that m * m maintains matrix number, the capable j column element of the k of T t _KjFor:

$t_{\mathrm{kj}}=\left\{\begin{array}{cc}\frac{v_{\mathrm{kj}}{\mathrm{\&gamma;}}_j{g}_{h_{j}k}}{g_{h_{j}j}}& j\&NotEqual;k\\ 0,& j=k\end{array}\right.,$ Wherein

I and E are m dimensional vector, I=[I ₁, I ₂..., I _m] ^T, E=[η ₁, η ₂..., η _m] ^T

Initial interference power according to a described m user is expressed as vector form I ⁽⁰⁾

According to I ⁽⁰⁾To I ^(m)=TI ^(m-1)+ E carries out iterative, obtains the presence of intercell interference that described user is subjected to.

9. a centralized interference calculation device that is used for OFDM networks is characterized in that, comprising:

First acquisition module, be used to obtain the user that each base station is served in the cell cluster of uplink service channel measurement information, intend the transmitting power and the target Signal to Interference plus Noise Ratio that adopt;

Analysis module is used for according to transmitting power and described target Signal to Interference plus Noise Ratio that described channel measurement information, described plan adopt described user's transmitting power being analyzed, and obtains the presence of intercell interference that described user is subjected to.

10. a centralized interference calculation device that is used for OFDM networks is characterized in that, comprising:

First acquisition module is used to obtain the user's that each base station is served in the cell cluster of downlink business channel measurement information, the initial interference power that receives and target Signal to Interference plus Noise Ratio;

Computing module is used for calculating the presence of intercell interference that described user is subjected to according to described channel measurement information, described initial interference power and described target Signal to Interference plus Noise Ratio.

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