CN105207758A - Method for selecting downlink, device for selecting downlinks and equipment - Google Patents

Abstract

The invention provides a method for selecting downlinks, a device for selecting downlinks and equipment. The method comprises the following steps that: channel information of a plurality of downlinks of one or more users is acquired; vectors in a plurality of ordered bases are determined as correlation vectors of the downlinks according to the channel information of the downlinks, correlation degree between the vectors and the downlinks satisfying a first predetermined condition, and ordered bases where the correlation vectors are located are determined as correlation ordered bases of the downlinks; the correlation degree between the correlation ordered bases of the downlinks is determined; and one or more downlinks of one or more users, used for MIMO spatial multiplexing, are selected from the plurality of downlinks according to the correlation vectors of the downlinks and the correlation degree between the correlation ordered bases of the downlinks. Compared with the prior art, and according to the method of the invention, the downlinks are selected based on the correlation vectors of the downlinks and the correlation degree between the correlation ordered bases of the downlinks, and therefore, inter-flow interference and inter-user interference can be decreased.

Description

A kind of for selecting the method for down link, device and equipment

Technical field

The present invention relates to down link and select field, particularly relate to a kind of in the base station of LTE network for selecting the method for down link, device and equipment.

Background technology

In a wireless communication system, transmitter and receiver uses multiple antenna, form multiple-input and multiple-output (MultiInputMultiOutput, MIMO) system, to improve the capacity of wireless communication system, improve communication quality.In mimo systems, consider interference and inter-user interference between stream, need to select suitable down link.And after have selected the multiple down links for MIMO, interference and inter-user interference between stream can be reduced by precoding technique.And how to select suitable down link to be a problem needing to solve.

Summary of the invention

The object of this invention is to provide a kind of in the base station of LTE for selecting method and the device of down link, and the base station of a kind of LTE.

According to an aspect of the present invention, there is provided a kind of in the base station of LTE for selecting the method for down link, wherein, this LTE network uses the code book comprising multiple multiple orderly bases of normal orthogonal, and be Linear Rotation transformation relation between described multiple orderly base, the method comprises the following steps:

-obtain the channel information of multiple down links of one or more user;

-according to the channel information of described each down link, for each down link determine in described multiple orderly base with the interconnection vector of the vector of this down link degree of correlation first predetermined condition as this down link, and the orderly base at this interconnection vector place is defined as the orderly base of association of this down link;

-determine described each down link the orderly base of each association between the degree of correlation;

-according to each interconnection vector of described each down link, and the degree of correlation between the orderly base of each association of described each down link, in described multiple down link, select one or more down links of the one or more users being used for MIMO space multi-way.

According to another aspect of the present invention, there is provided a kind of in the base station of LTE for selecting the device of down link, wherein, this LTE network uses the code book comprising multiple multiple orderly bases of normal orthogonal, and be Linear Rotation transformation relation between described multiple orderly base, this device comprises:

-for obtaining the device of the channel information of multiple down links of one or more user;

-for the channel information according to described each down link, for each down link determine in described multiple orderly base with the interconnection vector of the vector of this down link degree of correlation first predetermined condition as this down link, and the orderly base at this interconnection vector place is defined as the device of the orderly base of association of this down link;

-for determine described each down link the orderly base of each association between the device of the degree of correlation;

-for each interconnection vector according to described each down link, and the degree of correlation between the orderly base of each association of described each down link, in described multiple down link, select the device of one or more down links of the one or more users being used for MIMO space multi-way.

Compared with prior art, the present invention is based on the interconnection vector of each down link, and the degree of correlation between each orderly base selects down link, reduce interference and inter-user interference between stream.

Accompanying drawing explanation

By reading the detailed description done non-limiting example done with reference to the following drawings, other features, objects and advantages of the present invention will become more obvious:

Fig. 1 illustrates an exemplary topology figure according to LTE network of the present invention;

Fig. 2 illustrate according to one aspect of the invention in the base station of LTE for selecting the flow chart of the method for down link;

Fig. 3 illustrate according to a further aspect of the present invention in the base station of LTE for selecting the schematic diagram of the device of down link.

In accompanying drawing, same or analogous Reference numeral represents same or analogous parts.

Embodiment

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

Fig. 1 illustrates an exemplary topology figure according to LTE network of the present invention.In this embodiment, described LTE network comprises multiple base station 11, base station 12 ... base station 1M, and multiple subscriber equipment 21, subscriber equipment 22 ... subscriber equipment 2K.Predetermined code book C={C is preserved in each base station ₁, C ₂... C _l, predetermined code book can for comprising multiple multiple orderly base of normal orthogonal, and be any code book of Linear Rotation transformation relation between described multiple orderly base.Base station includes but not limited to eNodeB.A base station can be disposed in each community, and each base station can comprise several sector and the interface for transmission user business or service control can be used between the base stations to communicate mutually.Base station can directly or indirectly with each communications of user equipment.And each subscriber equipment can be any one can wirelessly directly or indirectly and the electronic equipment of base station communication, include but not limited to: mobile phone, PDA etc.In addition, as a kind of optimal way, each base station in this LTE network has many antennas, and each subscriber equipment also has many antennas.Thus, subscriber equipment 21, subscriber equipment, 22 ... subscriber equipment 2M, and base station forms the wireless communication system based on MIMO technology.Preferably, each subscriber equipment in this LTE network and base station adopt TDD mode (time-divisionduplexingmode, TDDmode) receive and send messages, but those skilled in the art should understand that, the pattern of each subscriber equipment and base station transceiver information is not limited with above-mentioned, such as this method principle can be applied in other equally, in the system of receiving and sending messages as adopted mode of frequency division duplexing (frequency-divisionduplexingmode, FDDmode).

Fig. 2 illustrate according to one aspect of the invention in the base station of LTE for selecting the flow chart of the method for down link.

Particularly, in step sl, base station obtains the channel information of each down link.In TDD network, utilize the reciprocity of up-downgoing channel, base station by obtaining the detectable signal that subscriber equipment sends, can estimate the channel information of this subscriber equipment to the up link of base station, and as the channel information of base station to the down link of subscriber equipment.This channel information can be preferably channel matrix.Wherein, for such as subscriber equipment 2i, Wo Menyong represent the channel matrix between base station and subscriber equipment 2i.The technology estimating channel information for base station and subscriber equipment according to the information received due to those skilled in the art is known, therefore is not described in detail in this.

In step s 2, base station is according to the channel information of described each down link, for each down link in each down channel determine in described multiple orderly base with the interconnection vector of the vector of this down link degree of correlation first predetermined condition as this down link, and the orderly base at this interconnection vector place is defined as the orderly base of association of this down link.In one embodiment, the first predetermined condition can be the highest with this down link degree of correlation.Further, in a preferred embodiment, described code book is designated as C={C ₁, C ₂... C _n, C _i∈ C ^[T*T]for the multiple orderly base of normal orthogonal of i-th in code book C, T is the antenna number of base station, C _i,kfor orderly base C _iin a kth base vector, for the channel matrix of the down channel to user j, arrange for carrying out the m after singular value decomposition to this channel matrix, it, for corresponding to the characteristic vector of the corresponding down link of m characteristic value to this user j, determines the vectorial C with this down link degree of correlation first predetermined condition according to following formula (1) _i,kinterconnection vector as this down link:

$C_{i,k}=\arg \underset{C_{i,k}\∈C}{\max }\left|\right|H_{i,m}^H{C}_{i,k}\left|\right|---\left(1\right)$

Further, base station is by C _i,kthe orderly base C at place _ibe defined as the orderly base of association of this down link.

It will be understood by those skilled in the art that herein, the description about the first predetermined condition is only exemplary and indefiniteness describes, exist various other implementation and do not deviate from spirit of the present invention or category, and be contained in this by reference.

Then, in step s3, the degree of correlation between the orderly base of each association of described each down link is determined in base station.In one embodiment, described code book is designated as C={C ₁, C ₂... C _n, C _i, C _j∈ C is i-th and a jth orderly base in code book C, C _{i, 1}for orderly base C _iin the 1st base vector, C _{j, 1}for orderly base C _jin the 1st base vector, calculate orderly base C according to following formula (2) _i, C _jbetween degree of correlation γ (C _{i, 1}, C _{j, 1}):

$\mathrm{\γ}(C_{i,1},C_{j,1})=\mathrm{Re}(C_{i,1}*C_{j,1}^H)---\left(2\right)$

Wherein, Re () represents the real part getting the multiplication of complex numbers.

In addition, in one embodiment, in advance the multiple orderly base in code book can also be arranged in a circle cyclic sequence by correlation size, guarantee there is larger correlation between adjacent orderly base, between the orderly base of spaced furthest, correlation is minimum.Herein, can according to this circle cyclic sequence determining orderly base by following formula (3):

$\underset{P}{\arg \min }\left\{\underset{i\∈N}{\mathrm{\Σ}}({\mathrm{\γ}}_{\left[i\right][i+n/2]}-{\mathrm{\γ}}_{\left[i\right][i-1]}-{\mathrm{\γ}}_{\left[i\right][i+1]})\right\}---\left(3\right)$

Wherein, P={N! All arrangements that the orderly base of N is possible }.

Further, two orderly base C of circle cyclic sequence sequence will can be pressed _iand C _jbetween distance L (C _i, C _j), i ≠ j is defined as following formula (4):

$L(C_i,C_j)=\left\{\begin{array}{c}\left|\right[i]-[j\left]\right|,1\&le;\left|\right[i]-[j\left]\right|\&le;N/2\\ N-\left|\right[i]-[j\left]\right|,N/2<\left|\right[i]-[j\left]\right|<N\end{array}\right.---\left(4\right)$

Wherein, [i] operates for mould N, and [i]-[j] is mould N subtraction.

Thus, during the degree of correlation between calculating two orderly bases, can directly draw according to the distance between two orderly bases.Distance is less, and be such as 1, then the degree of correlation is higher.Distance is larger, and be such as N/2, then the degree of correlation is less.

It will be understood by those skilled in the art that herein, the description about the degree of correlation determined between orderly base is only exemplary and indefiniteness describes, exist various other implementation and do not deviate from spirit of the present invention or category, and be contained in this by reference.

Then, in step s 4 which, base station is according to each interconnection vector of described each down link, and the degree of correlation between the orderly base of each association of described each down link, selects one or more down links of the one or more users being used for MIMO space multi-way in described multiple down link.

In one embodiment, base station first can according to certain strategy, and such as, poll, equitable proportion etc., select the first down link for MIMO, and wherein, the orderly base of association of this first down link is denoted as C _v1.Then, base station can according to each interconnection vector of described each down link, and the degree of correlation between the orderly base of association of described each down link, and described first down link, the one or more down links selecting to meet one or more users of following condition are continued in described multiple downlink relay:

The orderly base of association of selected down link and C _v1between degree of correlation second predetermined condition; And

Each is selected for the interconnection vector C of the down link of MIMO _{vi, Ki}at respective orderly base C _v1in the sequence number of residing the second subscript Ki different.

Herein, the second predetermined condition can be the orderly base of association and the C of selected down link _v1between relevance degree higher than certain threshold value.Preferably, the second predetermined condition also can be the orderly base of association and the C of selected down link _v1between relevance degree the highest.

It will be understood by those skilled in the art that herein, the description about the second predetermined condition is only exemplary and indefiniteness describes, exist various other implementation and do not deviate from spirit of the present invention or category, and be contained in this by reference.

In addition, in a preferred embodiment, after have selected the first down link for MIMO, base station selected the second down link for MIMO meeting above-mentioned condition, the orderly base of association of this second down link is denoted as C _v2.Then, base station can according to C _v1with C _v2between the degree of correlation, determine the down link number of MIMO.In one embodiment, C is worked as _v1with C _v2between the degree of correlation larger time, this down link number can be larger.Such as, by C _v1with C _v2between relevance degree be mapped to value in [0,1], when this relevance degree is 1, it can appear at such as C _v1with C _v2situation time identical, this down link number can be set to maximum, such as, be 4.When this relevance degree is less than 1 and is greater than the threshold value of certain setting, this down link number can be such as 2.When the threshold value of this relevance degree lower than this setting, this down link number can be such as 1.Preferably, the degree of correlation between each orderly base can also be precomputed and be stored as such as list, when carrying out down link and selecting, can directly inquire about this list thus avoid repeatedly double counting.Preferably, for each orderly base, by the degree of correlation of other orderly bases and this orderly base, other orderly bases can also be divided into groups.Such as, for orderly base C _v1, group 1 can comprise and C _v1the degree of correlation of orderly base is greater than the orderly base of certain setting threshold, and group 2 can comprise and C _v1the degree of correlation of orderly base is not more than the orderly base of certain setting threshold.Then work as C _v2during for organizing the orderly base in 1, this down link number can be set to larger value as 3; Work as C _v2during for organizing the orderly base in 2, this down link number can be set to less value as 2., each threshold value can be set according to such as empirical value or historical statistics value herein, and corresponding down link number.Further, preferably, threshold value and arranging of down link number can according to actual conditions dynamic conditioning such as system loads.It will be understood by those skilled in the art that herein, about determining the description of down link number to be only exemplary, indefiniteness describes, exist various other implementation and do not deviate from spirit of the present invention or category, and be contained in this by reference.

Then, base station is according to the interconnection vector of described each down link, and the degree of correlation between the orderly base of the association of each down link, and according to the first down link and the second down link, continue selector in multiple downlink relay to close one or more down links of condition of stating, and the number of selected all down links for MIMO is not more than down link number.Such as, when down link number is 4, except the first down link and the second down link, 2 down links also can be selected in base station, and selected down link meets above-mentioned condition.

In a preferred embodiment, after selecting the one or more down links for one or more users of MIMO, selected down link is designated as { L ₁, L ₂... Ln}, for { L ₁, L ₂... each down link Li in Ln}, its interconnection vector is denoted as C _{vi, Ki}, it is orderly base C _viki row, and orderly for the association of the first down link base is denoted as C _v1.Pre-coding matrix then for MIMO can by C _{v1, K1}, C _{v1, K2}... C _{v1, Kn}composition, wherein C _{v1, Ki}the orderly base C of association for described first down link _v1k _irow.Also namely, as the interconnection vector of down link selected be C _{vi, Ki}, it associates orderly base is C _vi, it is different from C _v1time, use C _{v1, Ki}be similar to and replace C _{vi, Ki}using as the vector in pre-coding matrix.Such as, the down link selected be { L ₁, L ₂, L ₃, L ₄, its interconnection vector is { C _5,1, C _5,2, C _2,3, C _4,5, wherein the first link is L ₁, its interconnection vector is C _5,1, it associates orderly base is C ₅.Then pre-coding matrix will for by column vector C _5,1, C _5,2, C _5,3, C _5,5the matrix of composition, wherein uses C _5,3, C _5,5approximate replacement C _2,3, C _4,5.Due to as mentioned above, be Linear Rotation transformation relation between each orderly base, and the orderly base C of the association of selected each down link _viwith the first down link associate orderly base C _v1degree of correlation second predetermined condition, preferably, its can be the degree of correlation higher than certain threshold value, then use C _{v1, Ki}be similar to and replace C _{vi, Ki}the energy loss that composition pre-coding matrix causes is less.And due to C _{vi, Ki}can by C _{v1, Ki}approximate substitution, due to as previously mentioned, the interconnection vector C of selected each down link _{vi, Ki}the sequence number of the second subscript Ki residing in respective orderly base is different, also, can use C _v1in there is different second time target vector to each C of approximate substitution respectively _{vi, Ki}.Due to as previously mentioned, the orderly base in code book is the multiple orderly base of normal orthogonal, also i.e. C _v1in there is different second time target vector C _{v1, Ki}orthogonal, also, each interconnection vector C of its approximate substitution _{vi, Ki}nearly orthogonal each other, therefore when carrying out MIMO, its interference is to each other less.Due to said method, pre-coding matrix can according to the interconnection vector of selected down link with associate orderly base and draw fast, thus avoid complicated pre-coding matrix and calculate, improve systematic function.

Fig. 3 illustrate according to a further aspect of the present invention in the base station of LTE for selecting the schematic diagram of the device of down link.

Particularly, the device of the channel information for obtaining each down link of base station, hereinafter referred to as the first acquisition device 31, obtains the channel information of each down link.In TDD network, utilize the reciprocity of up-downgoing channel, first acquisition device 31 by obtaining the detectable signal that subscriber equipment sends, can estimate the channel information of this subscriber equipment to the up link of base station, and as the channel information of base station to the down link of subscriber equipment.This channel information can be preferably channel matrix.Wherein, for such as subscriber equipment 2i, Wo Menyong represent the channel matrix between base station and subscriber equipment 2i.The technology estimating channel information for base station and subscriber equipment according to the information received due to those skilled in the art is known, therefore is not described in detail in this.

Then, base station for the channel information according to described each down link, for each down link in each down channel determine in described multiple orderly base with the interconnection vector of the vector of this down link degree of correlation first predetermined condition as this down link, and the orderly base at this interconnection vector place is defined as the device of the orderly base of association of this down link, determine the interconnection vector of each down link hereinafter referred to as association determining device 32 and associate orderly base.In one embodiment, the first predetermined condition can be the highest with this down link degree of correlation.Further, in a preferred embodiment, described code book is designated as C={C ₁, C ₂... C _n, C _i∈ C ^[T*T]for the multiple orderly base of normal orthogonal of i-th in code book C, T is the antenna number of base station, C _i,kfor orderly base C _iin a kth base vector, for the channel matrix of the down channel to user j, arrange for carrying out the m after singular value decomposition to this channel matrix, it is for corresponding to the characteristic vector of the corresponding down link of m characteristic value to this user j, and association determining device 32 determines the vectorial C with this down link degree of correlation first predetermined condition according to following formula (1) _i,kinterconnection vector as this down link:

$C_{i,k}=\arg \underset{C_{i,k}\&Element;C}{\max }\left|\right|H_{i,m}^H{C}_{i,k}\left|\right|---\left(1\right)$

Further, base station is by C _i,kthe orderly base C at place _ibe defined as the orderly base of association of this down link.

It will be understood by those skilled in the art that herein, the description about the first predetermined condition is only exemplary and indefiniteness describes, exist various other implementation and do not deviate from spirit of the present invention or category, and be contained in this by reference.

Then, base station for determine described each down link the orderly base of each association between the device of the degree of correlation, the degree of correlation between the orderly base of each association determining each down link hereinafter referred to as degree of correlation determining device 33.In one embodiment, described code book is designated as C={C ₁, C ₂... C _n, C _i, C _j∈ C is i-th and a jth orderly base in code book C, C _{i, 1}for orderly base C _iin the 1st base vector, C _{j, 1}for orderly base C _jin the 1st base vector, degree of correlation determining device 33 calculates orderly base C according to following formula (2) _i, C _jbetween degree of correlation γ (C _{i, 1}, C _{j, 1}):

$\mathrm{\&gamma;}(C_{i,1},C_{j,1})=\mathrm{Re}(C_{i,1}*C_{j,1}^H),---\left(2\right)$

Wherein, Re () represents the real part getting the multiplication of complex numbers.

In addition, in one embodiment, multiple orderly base in code book can also be arranged in a circle cyclic sequence by correlation size by degree of correlation determining device 33 in advance, and guarantee there is larger correlation between adjacent orderly base, between the orderly base of spaced furthest, correlation is minimum.Herein, degree of correlation determining device 33 can according to this circle cyclic sequence determining orderly base by following formula (3):

$\underset{P}{\arg \min }\left\{\underset{i\&Element;N}{\mathrm{\&Sigma;}}({\mathrm{\&gamma;}}_{\left[i\right][i+n/2]}-{\mathrm{\&gamma;}}_{\left[i\right][i-1]}-{\mathrm{\&gamma;}}_{\left[i\right][i+1]})\right\}---\left(3\right)$

Wherein, P={N! All arrangements that the orderly base of N is possible }.

Further, degree of correlation determining device 33 can will press two orderly base C of circle cyclic sequence sequence _iand C _jbetween distance L (C _i, C _j), i ≠ j is defined as following formula (4):,

$L(C_i,C_j)=\left\{\begin{array}{c}\left|\right[i]-[j\left]\right|,1\&le;\left|\right[i]-[j\left]\right|\&le;N/2\\ N-\left|\right[i]-[j\left]\right|,N/2<\left|\right[i]-[j\left]\right|<N\end{array}\right.---\left(4\right)$

Wherein, [i] operates for mould N, and [i]-[j] is mould N subtraction.

Thus during the degree of correlation between calculating two orderly bases, degree of correlation determining device 33 can directly draw according to the distance between two orderly bases.Distance is less, and be such as 1, then the degree of correlation is higher.Distance is larger, and be such as N/2, then the degree of correlation is less.

It will be understood by those skilled in the art that herein, the description about the degree of correlation determined between orderly base is only exemplary and indefiniteness describes, exist various other implementation and do not deviate from spirit of the present invention or category, and be contained in this by reference.

Then, base station for each interconnection vector according to described each down link, and the degree of correlation between the orderly base of each association of described each down link, in described multiple down link, select the device of one or more down links of the one or more users being used for MIMO space multi-way, select hereinafter referred to as choice device 34 down link being used for MIMO.

In one embodiment, choice device 34 first can according to certain strategy, and such as, poll, equitable proportion etc., select the first down link for MIMO, and wherein, the orderly base of association of this first down link is denoted as C _v1.Then, choice device 34 can according to each interconnection vector of described each down link, and the degree of correlation between the orderly base of association of described each down link, and described first down link, the one or more down links selecting to meet one or more users of following condition are continued in described multiple downlink relay:

The orderly base of association of selected down link and C _v1between degree of correlation second predetermined condition; And

Each is selected for the interconnection vector C of the down link of MIMO _{vi, Ki}at respective orderly base C _v1in the sequence number of residing the second subscript Ki different.

Herein, the second predetermined condition can be the orderly base of association and the C of selected down link _v1between relevance degree higher than certain threshold value.Preferably, the second predetermined condition also can be the orderly base of association and the C of selected down link _v1between relevance degree the highest.

It will be understood by those skilled in the art that herein, the description about the second predetermined condition is only exemplary and indefiniteness describes, exist various other implementation and do not deviate from spirit of the present invention or category, and be contained in this by reference.

In addition, in a preferred embodiment, after have selected the first down link for MIMO, choice device 34 selector closes second down link for MIMO of condition of stating, and the orderly base of association of this second down link is denoted as C _v2.Then, choice device 34 can according to C _v1with C _v2between the degree of correlation, determine the down link number of MIMO.In one embodiment, C is worked as _v1with C _v2between the degree of correlation larger time, this down link number can be larger.Such as, by C _v1with C _v2between relevance degree be mapped to value in [0,1], when this relevance degree is 1, it can appear at such as C _v1with C _v2situation time identical, this down link number can be set to maximum, such as, be 4.When this relevance degree is less than 1 and is greater than the threshold value of certain setting, this down link number can be such as 2.When the threshold value of this relevance degree lower than this setting, this down link number can be such as 1.Preferably, the degree of correlation between each orderly base can also be precomputed and be stored as such as list, when carrying out down link and selecting, can directly inquire about this list thus avoid repeatedly double counting.Preferably, for each orderly base, by the degree of correlation of other orderly bases and this orderly base, other orderly bases can also be divided into groups.Such as, for orderly base C _v1, group 1 can comprise and C _v1the degree of correlation of orderly base is greater than the orderly base of certain setting threshold, and group 2 can comprise and C _v1the degree of correlation of orderly base is not more than the orderly base of certain setting threshold.Then work as C _v2during for organizing the orderly base in 1, this down link number can be set to larger value as 3; Work as C _v2during for organizing the orderly base in 2, this down link number can be set to less value as 2., each threshold value can be set according to such as empirical value or historical statistics value herein, and corresponding down link number.Further, preferably, threshold value and arranging of down link number can according to actual conditions dynamic conditioning such as system loads.It will be understood by those skilled in the art that herein, about determining the description of down link number to be only exemplary, indefiniteness describes, exist various other implementation and do not deviate from spirit of the present invention or category, and be contained in this by reference.

Then, choice device 34 is according to the interconnection vector of described each down link, and the degree of correlation between the orderly base of the association of each down link, and according to the first down link and the second down link, continue selector in multiple downlink relay to close one or more down links of condition of stating, and the number of selected all down links for MIMO is not more than down link number.Such as, when down link number is 4, except the first down link and the second down link, choice device 34 also can select 2 down links, and selected down link meets above-mentioned condition.

In a preferred embodiment, after selecting the one or more down links for one or more users of MIMO, selected down link is designated as { L ₁, L ₂... Ln}, for { L ₁, L ₂... each down link Li in Ln}, its interconnection vector is denoted as C _{vi, Ki}, it is orderly base C _viki row, and orderly for the association of the first down link base is denoted as C _v1.Then choice device 34 can use C _{v1, K1}, C _{v1, K2}... C _{v1, Kn}composition is used for the pre-coding matrix of MIMO, wherein C _{v1, Ki}the orderly base C of association for described first down link _v1ki row.Also namely, as the interconnection vector of down link selected be C _{vi, Ki}, it associates orderly base is C _vi, it is different from C _v1time, use C _{v1, Ki}be similar to and replace C _{vi, Ki}using as the vector in pre-coding matrix.Such as, the down link selected be { L ₁, L ₂, L ₃, L ₄, its interconnection vector is { C _5,1, C _5,2, C _2,3, C _4,5, wherein the first link is L ₁, its interconnection vector is C _5,1, it associates orderly base is C ₅.Then pre-coding matrix will for by column vector C _5,1, C _5,2, C _5,3, C _5,5the matrix of composition, wherein uses C _5,3, C _5,5approximate replacement C _2,3, C _4,5.Due to as mentioned above, be Linear Rotation transformation relation between each orderly base, and the orderly base C of the association of selected each down link _viwith the first down link associate orderly base C _v1degree of correlation second predetermined condition, preferably, its can be the degree of correlation higher than certain threshold value, then use C _{v1, Ki}be similar to and replace C _{vi, Ki}the energy loss that composition pre-coding matrix causes is less.And due to C _{vi, Ki}can by C _{v1, Ki}approximate substitution, due to as previously mentioned, the interconnection vector C of selected each down link _{vi, Ki}the sequence number of the second subscript Ki residing in respective orderly base is different, also, can use C _v1in there is different second time target vector to each C of approximate substitution respectively _{vi, Ki}.Due to as previously mentioned, the orderly base in code book is the multiple orderly base of normal orthogonal, also i.e. C _v1in there is different second time target vector C _{v1, Ki}orthogonal, also, each interconnection vector C of its approximate substitution _{vi, Ki}nearly orthogonal each other, therefore when carrying out MIMO, its interference is to each other less.Due to said method, pre-coding matrix can according to the interconnection vector of selected down link with associate orderly base and draw fast, thus avoid complicated pre-coding matrix and calculate, improve systematic function.

It will be understood by those skilled in the art that each device above-mentioned or module can be the devices be separated, also can be partly or entirely in one apparatus integrated.

It should be noted that the present invention can be implemented in the assembly of software and/or software restraint, such as, application-specific integrated circuit (ASIC) (ASIC), general object computer or any other similar hardware device can be adopted to realize.In one embodiment, software program of the present invention can perform to realize step mentioned above or function by processor.Similarly, software program of the present invention (comprising relevant data structure) can be stored in computer readable recording medium storing program for performing, such as, and RAM memory, magnetic or CD-ROM driver or floppy disc and similar devices.In addition, steps more of the present invention or function can adopt hardware to realize, such as, as coordinating with processor thus performing the circuit of each step or function.

In addition, a part of the present invention can be applied to computer program, such as computer program instructions, when it is performed by computer, by the operation of this computer, can call or provide according to method of the present invention and/or technical scheme.And call the program command of method of the present invention, may be stored in fixing or moveable recording medium, and/or be transmitted by the data flow in broadcast or other signal bearing medias, and/or be stored in the working storage of the computer equipment run according to described program command.At this, comprise a device according to one embodiment of present invention, this device comprises the memory for storing computer program instructions and the processor for execution of program instructions, wherein, when this computer program instructions is performed by this processor, trigger this plant running based on the aforementioned method according to multiple embodiment of the present invention and/or technical scheme.

To those skilled in the art, obviously the invention is not restricted to the details of above-mentioned one exemplary embodiment, and when not deviating from spirit of the present invention or essential characteristic, the present invention can be realized in other specific forms.Therefore, no matter from which point, all should embodiment be regarded as exemplary, and be nonrestrictive, scope of the present invention is limited by claims instead of above-mentioned explanation, and all changes be therefore intended in the implication of the equivalency by dropping on claim and scope are included in the present invention.Any Reference numeral in claim should be considered as the claim involved by limiting.In addition, obviously " comprising " one word do not get rid of other unit or step, odd number does not get rid of plural number.Multiple devices of stating in device claim also can be realized by software or hardware by a device.First, second word such as grade is used for representing title, and does not represent any specific order.

Claims (13)

1. in the base station of LTE network for selecting a method for down link, wherein, this LTE network uses the code book comprising multiple multiple orderly bases of normal orthogonal, and is Linear Rotation transformation relation between described multiple orderly base, and the method comprises:

-obtain the channel information of multiple down links of one or more user;

-according to the channel information of described each down link, for each down link determine in described multiple orderly base with the interconnection vector of the vector of this down link degree of correlation first predetermined condition as this down link, and the orderly base at this interconnection vector place is defined as the orderly base of association of this down link;

-determine described each down link the orderly base of each association between the degree of correlation;

-according to each interconnection vector of described each down link, and the degree of correlation between the orderly base of each association of described each down link, in described multiple down link, select one or more down links of the one or more users being used for MIMO space multi-way.

2. method according to claim 1, wherein, according to the channel information of described each down link, for each down link determine in described multiple orderly base with the interconnection vector of the vector of this down link degree of correlation first predetermined condition as this down link, and the step orderly base at this interconnection vector place being defined as the orderly base of association of this down link comprises:

-described code book is C={C ₁, C ₂... C _n, C _i∈ C ^[T*T]for the multiple orderly base of normal orthogonal of i-th in code book C, T is the antenna number of described base station, C _i,kfor orderly base C _iin a kth base vector, for the channel matrix of the down channel to user j, arrange for carrying out the m after singular value decomposition to this channel matrix, it is the characteristic vector of the corresponding down link of m characteristic value corresponded to this user j, determines the vectorial C with this down link degree of correlation first predetermined condition according to following formula _i,kinterconnection vector as this down link:

$C_{i,k}=\arg \underset{C_{i,k}\&Element;C}{\max }\left|\right|H_{i,m}^H{C}_{i,k}\left|\right|;$

-according to determined this interconnection vector C _i,k, by the orderly base C at this vectorial place _ibe defined as the orderly base of association of this down link.

3. method according to claim 1 and 2, wherein, the step of the degree of correlation between the described orderly base of each association determining described each down link comprises:

-described code book is C={C ₁, C ₂... C _n, C _i, C _j∈ C is i-th and a jth orderly base in code book C, C _{i, 1}for orderly base C _iin the 1st base vector, C _{j, 1}for orderly base C _jin the 1st base vector, according to the orderly base C of following formulae discovery _i, C _jbetween degree of correlation γ (C _{i, 1}, C _{j, 1}):

wherein, Re () represents the real part getting the multiplication of complex numbers.

4. according to the method in any one of claims 1 to 3, wherein, according to each interconnection vector of described each down link, and the degree of correlation between the orderly base of each association of described each down link, in described multiple down link, select the step of one or more down links of the one or more users being used for MIMO to comprise:

-select the first down link being used for MIMO, wherein, the orderly base of association of this first down link is designated as C _v1;

-according to each interconnection vector of described each down link, and the degree of correlation between the orderly base of association of described each down link, and described first down link, the one or more down links selecting to meet one or more users of following condition are continued in described multiple downlink relay:

The orderly base of association of selected down link and C _v1between degree of correlation second predetermined condition; And

Each is selected for the interconnection vector C of the down link of MIMO _{vi, Ki}the sequence number of the second subscript Ki residing in respective orderly base is different.

5. according to the method described in claim 4, wherein, according to each interconnection vector of described each down link, and the degree of correlation between the orderly base of association of described each down link, and described first down link, continue in described multiple downlink relay the step selecting to meet one or more down links of one or more users of described condition and comprise:

-select the second down link for MIMO meeting described condition;

-according to the orderly base of association of described first down link and the degree of correlation associated between orderly base of described second down link, determine the down link number of MIMO;

-according to the interconnection vector of described each down link, and the degree of correlation between the orderly base of association of described each down link, and according to described first down link and the second down link, continue the one or more down links selecting to meet described condition in described multiple downlink relay, and the number of selected all down links for MIMO is not more than described down link number.

6. the method according to any one of claim 4 to 5, wherein, also comprises:

-after selecting the one or more down links for one or more users of MIMO, the down link selected be designated as { L ₁, L ₂... Ln}, for { L ₁, L ₂... each down link Li in Ln}, its interconnection vector is denoted as C _{vi, Ki}, it is orderly base C _viki row, then for the pre-coding matrix of MIMO by C _{v1, K1}, C _{v1, K2}... C _{v1, Kn}composition, wherein C _{v1, Ki}the orderly base C of association for described first down link _v1k _irow.

7. in the base station of LTE network for selecting a device for down link, wherein, this LTE network uses the code book comprising multiple multiple orderly bases of normal orthogonal, and is Linear Rotation transformation relation between described multiple orderly base, and this device comprises:

-for obtaining the device of the channel information of multiple down links of one or more user;

-for the channel information according to described each down link, for each down link determine in described multiple orderly base with the interconnection vector of the vector of this down link degree of correlation first predetermined condition as this down link, and the orderly base at this interconnection vector place is defined as the device of the orderly base of association of this down link;

-for determine described each down link the orderly base of each association between the device of the degree of correlation;

-for each interconnection vector according to described each down link, and the degree of correlation between the orderly base of each association of described each down link, in described multiple down link, select the device of one or more down links of the one or more users being used for MIMO space multi-way.

8. device according to claim 7, wherein, for the channel information according to described each down link, for each down link determine in described multiple orderly base with the interconnection vector of the vector of this down link degree of correlation first predetermined condition as this down link, and the device orderly base at this interconnection vector place being defined as the orderly base of association of this down link is used for:

-described code book is C={C ₁, C ₂... C _n, C _i∈ C ^[T*T]for the multiple orderly base of normal orthogonal of i-th in code book C, T is the antenna number of described base station, C _i,kfor orderly base C _iin a kth base vector, for the channel matrix of the down channel to user j, arrange for carrying out the m after singular value decomposition to this channel matrix, it is the characteristic vector of the corresponding down link of m characteristic value corresponded to this user j, determines the vectorial C with this down link degree of correlation first predetermined condition according to following formula _i,kinterconnection vector as this down link:

$C_{i,k}=\arg \underset{C_{i,k}\&Element;C}{\max }\left|\right|H_{i,m}^H{C}_{i,k}\left|\right|;$

-according to determined this interconnection vector C _i,k, by the orderly base C at this vectorial place _ibe defined as the orderly base of association of this down link.

9. the device according to claim 7 or 8, wherein, the device of the degree of correlation between the described orderly base of each association for determining described each down link for:

-described code book is C={C ₁, C ₂... C _n, C _i, C _j∈ C is i-th and a jth orderly base in code book C, C _{i, 1}for orderly base C _iin the 1st base vector, C _{j, 1}for orderly base C _jin the 1st base vector, according to the orderly base C of following formulae discovery _i, C _jbetween degree of correlation γ (C _{i, 1}, C _{j, 1}):

wherein, Re () represents the real part getting the multiplication of complex numbers.

10. the device according to any one of claim 7 to 9, wherein, for each interconnection vector according to described each down link, and the degree of correlation between the orderly base of each association of described each down link, in described multiple down link, select the device of one or more down links of the one or more users being used for MIMO to be used for:

-select the first down link being used for MIMO, wherein, the orderly base of association of this first down link is designated as C _v1;

-according to each interconnection vector of described each down link, and the degree of correlation between the orderly base of association of described each down link, and described first down link, the one or more down links selecting to meet one or more users of following condition are continued in described multiple downlink relay:

The orderly base of association of selected down link and C _v1between degree of correlation second predetermined condition; And

Each is selected for the interconnection vector C of the down link of MIMO _{vi, Ki}the second subscript K residing in respective orderly base _isequence number different.

11. according to the device described in claim 10, wherein, for each interconnection vector according to described each down link, and the degree of correlation between the orderly base of association of described each down link, and described first down link, continue in described multiple downlink relay the device selecting to meet one or more down links of one or more users of described condition for:

-select the second down link for MIMO meeting described condition;

-according to the orderly base of association of described first down link and the degree of correlation associated between orderly base of described second down link, determine the down link number of MIMO;

-according to the interconnection vector of described each down link, and the degree of correlation between the orderly base of association of described each down link, and according to described first down link and the second down link, continue the one or more down links selecting to meet described condition in described multiple downlink relay, and the number of selected all down links for MIMO is not more than described down link number.

12. according to claim 10 to the device according to any one of 11, wherein for each interconnection vector according to described each down link, and the degree of correlation between the orderly base of association of described each down link, and described first down link, described multiple downlink relay continue the device selecting to meet one or more down links of one or more users of described condition also for:

-after selecting the one or more down links for one or more users of MIMO, the down link selected be designated as { L ₁, L ₂... Ln}, for { L ₁, L ₂... each down link Li in Ln}, its interconnection vector is denoted as C _{vi, Ki}, it is orderly base C _viki row, then for the pre-coding matrix of MIMO by C _{v1, K1}, C _{v1, K2}... C _{v1, Kn}composition, wherein C _{v1, Ki}the orderly base C of association for described first down link _v1ki row.

13. 1 kinds of base stations comprising the LTE network of device according to any one of claims call 7-12.