CN102186178B - Intercell interference cooperation method for cooperation multipoint system - Google Patents

Intercell interference cooperation method for cooperation multipoint system Download PDF

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CN102186178B
CN102186178B CN 201110109593 CN201110109593A CN102186178B CN 102186178 B CN102186178 B CN 102186178B CN 201110109593 CN201110109593 CN 201110109593 CN 201110109593 A CN201110109593 A CN 201110109593A CN 102186178 B CN102186178 B CN 102186178B
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joint transmission
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residential quarter
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崔琪楣
陶小峰
杨姗
张平
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Beijing University of Posts and Telecommunications
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Abstract

The invention relates to the technical field of wireless communications, and provides an intercell interference cooperation method for a cooperation multipoint system. The method comprises the steps: users are divided into joint transmission users and non-joint transmission users according to the geographical positions of the users; each cell carries out initial resource scheduling respectively according to certain rules; pre-coded matrixes of all scheduled users are calculated according to an initial scheduling result of all the cells and the maximized signal-to-noise ratio; and all the cells update the scheduled and pre-coded results one by one in sequence according to a certain sequence, one-time updating of the scheduled and the pre-coded results of all the cells is taken as one-time iteration, and one-time or multi-time iteration can be carried out. In the intercell interference cooperation method, effective cooperation is carried out on intercell interference in the cooperation multipoint system, so that the performance of the system can be obviously enhanced and especially the service quality of edge users of the cells is improved.

Description

A kind of inter-cell interference coordination method for Synergistic multi-point system
Technical field
The present invention relates to wireless communication field, particularly relate to a kind of inter-cell interference coordination method for Synergistic multi-point system.
Background technology
In 3GPP (3rd Generation Partnership Project, third generation partner program) LTE (long term evolution, Long Term Evolution) system, in order to improve spectrum efficiency, the multiplexing factor of system frequency is set at 1 or near 1.This means that all residential quarters all can transmit at identical running time-frequency resource, thereby cause serious presence of intercell interference.In order effectively to suppress presence of intercell interference, particularly improve community marginal user performance, (coordinated multiple point transmission/reception, CoMP) technology is by in the framework of the to LTE-Advanced (advanced LTE) for cooperative multipoint transmission/reception.Descending CoMP supports two kinds of transmission meanss: joint transmission (joint transmission, JT) and the coordinates beam figuration (coordinated beamforming, CB).
For JT, a plurality of residential quarters are arranged simultaneously to a user (UE) emission data, thereby can effectively strengthen the received signal quality of UE.But in the JT pattern, because a plurality of residential quarters all need to distribute identical resource to give a UE, the resource that this UE takies is along with number of cells promotes at double, the UE decreased number that system can serve at synchronization.Therefore, though JT can promote cell-edge performance, can not strengthen the residential quarter average throughput.
In the CB pattern, each UE is still by a residential quarter service, but the wave beam forming matrix of UE is coordinated to determine by a plurality of residential quarters.Adopt suitable CB scheme, can reduce presence of intercell interference, improve systematic function.But traditional CB precoding vector obtains by iterative manner, and its amount of calculation is very high, and is not suitable for actual LTE-Advanced system.How to design the CB algorithm, when systematic function was strengthened, effectively controlling computation complexity also was a vital problem.
Summary of the invention
(1) technical problem that will solve
Shortcoming at prior art, the present invention is in order to solve the problem that the joint transmission mode can not bring the residential quarter average throughput to gain in the prior art, proposition is carried out combination with the mode of joint transmission and coordinates beam figuration, to strengthen system cell average behavior and cell-edge performance simultaneously.
(2) technical scheme
For this reason, the present invention adopts following technical scheme to carry out particularly:
At first, the invention provides a kind of inter-cell interference coordination method for Synergistic multi-point system, described method comprises step:
According to the residing geographical position of user, it is divided into joint transmission user and non-joint transmission user;
The initial resource scheduling is carried out independently of one another according to certain criterion in each residential quarter;
Let out according to the initial schedule result of all residential quarters and maximization letter and to make an uproar than criterion, calculate all scheduled users' pre-coding matrix;
Scheduling result and precoding result are upgraded in certain sequence successively one by one in each residential quarter, and the scheduling result of all residential quarters and precoding result upgrade and once be considered as iteration one time, carry out the one or many iteration.
Preferably, described according to the residing geographical position of user, its step that is divided into joint transmission user and non-joint transmission user is specially:
Cell Edge User classifies as the joint transmission user, and joint transmission user is its transmitting data information by two above residential quarters;
Cell Center User classifies as non-joint transmission user, and non-joint transmission user is its transmitting data information by a residential quarter.
Preferably, the criterion of carrying out described scheduling of resource comprises: poll, equitable proportion and/or maximization signal interference ratio.
Preferably, described maximization letter is let out and is made an uproar than in the criterion:
Described letter is let out the ratio of making an uproar than referring to signal power and leakage power and noise power sum, and wherein, described signal power refers to the signal power that this residential quarter institute dispatched users receives; Described leakage power refers to the interference power sum that this cell downlink transmits other cell schedulings are caused to the user on the same asset; Described noise power is that thermal noise and receiving terminal interference coefficient are at the product of linear domain.
Preferably, the more fresh target of described scheduling result is, avoid as far as possible in the neighbor cell, two close users in geographical position are dispatched on the identical resource;
Described precoding result's more fresh target is according to the up-to-date scheduling result in each residential quarter, to recomputate the pre-coding matrix of current area.
Preferably, the calculation criterion of pre-coding matrix is that described maximization letter is let out to make an uproar and compared criterion in the described iteration.
(3) beneficial effect
In the method provided by the invention, carried out effective coordination at the presence of intercell interference in the cooperative multicast system, be specially adapted to significantly to strengthen the service quality of systematic function, particularly Cell Edge User in the descending CoMP system.
Description of drawings
Fig. 1 is for being used for the inter-cell interference coordination method flow chart of Synergistic multi-point system among the present invention;
Fig. 2 is the system schematic of joint transmission user and non-joint transmission user in the embodiments of the invention;
Fig. 3 is the system schematic when carrying out the coordinates beam figuration in the embodiments of the invention;
Fig. 4 a carries out iterative coordination scheduling system schematic before in the embodiments of the invention;
Fig. 4 b carries out iterative coordination scheduling system schematic afterwards in the embodiments of the invention.
Embodiment
Below in conjunction with the accompanying drawing in the embodiment of the invention, the technical scheme in the embodiment of the invention is clearly and completely described, obviously, described embodiment is a part of embodiment of the present invention, rather than whole embodiment.Based on the embodiment among the present invention, the every other embodiment that those of ordinary skills obtain under the prerequisite of not making creative work belongs to the scope of protection of the invention.
The objective of the invention is to propose a kind of inter-cell interference coordination method that is applicable to descending CoMP system, to improve systematic function, particularly Cell Edge User throughput.For achieving the above object, the invention provides the coordination approach of presence of intercell interference in a kind of effectively reduction system, comprising:
Step 1: according to the residing geographical position of UE, it is divided into JT UE and non-JT UE.
Wherein, Cell Edge User is JT UE, and JT UE is its transmitting data information by two or more residential quarters; Cell Center User is non-JT UE, and non-JT UE is its transmitting data information by a residential quarter.
Step 2: the initial resource scheduling is carried out independently of one another according to certain criterion in each residential quarter.
The criterion that scheduling of resource is carried out in the residential quarter can be poll, equitable proportion, maximization signal interference ratio etc.
Step 3: according to initial schedule result and maximization SLNR (letter is let out the ratio of making an uproar, the Signal to leakage and noise ratio) criterion of all residential quarters, calculate the pre-coding matrix of all UE that are scheduled.
Wherein, SLNR is the implementation of a kind of CB, and this scheme can obtain the linear predictive coding matrix of closed loop, when guaranteeing systematic function, can effectively reduce the processing complexity.SLNR refers to the ratio of signal power and leakage and noise power sum.Signal power refers to the signal power that UE that dispatch this residential quarter receives.Leakage power refers to that this cell downlink transmits, the interference power sum that other cell schedulings are caused to the UE on the same asset.Noise power is that thermal noise and receiving terminal interference coefficient are at the product of linear domain.
Step 4: scheduling and precoding result are upgraded in certain sequence successively one by one in each residential quarter.The scheduling of all residential quarters and precoding result upgrade and once are considered as iteration one time.Can carry out the one or many iteration.
Wherein, the target that scheduling result is upgraded is, avoid as far as possible in the neighbor cell, two close UE in geographical position are dispatched on the identical resource.
The target that the precoding result upgrades is according to the up-to-date scheduling result in each residential quarter, to recomputate the pre-coding matrix of current area.Its calculation criterion is with step 3.
Below in conjunction with each accompanying drawing the preferred embodiments of the present invention are described further.The flow chart of inter-cell interference coordination method proposed by the invention as shown in Figure 1, wherein each step further adopts following preferred mode to carry out:
Step 1: according to the residing geographical position of UE, it is divided into JT UE and non-JT UE.
Wherein, Cell Edge User is JT UE, and JT UE is its transmitting data information by two or more residential quarters; Cell Center User is non-JT UE, and non-JT UE is its transmitting data information by a residential quarter.As shown in Figure 2, UE1 is Cell Edge User, therefore classifies as JT UE, is its transmitting data information simultaneously by cell (residential quarter) 1 and cell2; UE2 is Cell Center User, classifies as non-JT UE, is its transmitting data information by cell 1.
For each UE, will be defined as the main plot with the best residential quarter of its channel status.Further, the sets definition that will constitute for all residential quarters of its service the CoMP transmission collection of UE for this reason.Use Att Enanchor, kExpression UE k is the fading channel between its main plot.Wherein, fading channel comprises path loss, shadow fading, penetration loss and fan antenna gain.Define two fading channel threshold value A tten Thre1And Atten Thre2:
If Atten Anchor, k〉=Atten Thre1, UEk is JT UE, in its CoMP transmission collection 3 residential quarters is arranged, and these 3 residential quarters be in all residential quarters with 3 residential quarters of UE k fading channel minimum;
If Atten Thre1＞Atten Anchor, k〉=Atten Thre2, UEk is JT UE, in its CoMP transmission collection 2 residential quarters is arranged, and these 2 residential quarters be in all residential quarters with 2 residential quarters of UE k fading channel minimum;
If Atten Anchor, k＜Atten Thre2, UE k is non-JT UE, in its CoMP transmission collection 1 residential quarter is arranged, and this residential quarter be in all residential quarters with the residential quarter of UE k fading channel minimum.
Step 2: the initial resource scheduling is carried out independently of one another according to certain criterion in each residential quarter.
The criterion that scheduling of resource is carried out in the residential quarter can be: poll, equitable proportion and/or maximization signal interference ratio etc.For JT UE, when being its Resources allocation, the same asset of all residential quarters in its CoMP transmission collection be distributed to this UE.
Step 3: according to initial schedule result and maximization SLNR (letter is let out the ratio of making an uproar, the Signal to leakage and noise ratio) criterion of all residential quarters, calculate the pre-coding matrix of all UE that are scheduled.
Wherein, SLNR is the implementation of a kind of CB, and this scheme can obtain the linear predictive coding matrix of closed loop, when guaranteeing systematic function, can effectively reduce the processing complexity.SLNR refers to the ratio of signal power and leakage and noise power sum.Signal power refers to the signal power that UE that dispatch this residential quarter receives.Leakage power refers to that this cell downlink transmits, the interference power sum that other cell schedulings are caused to the UE on the same asset.Noise power comprises thermal noise and receiving terminal interference coefficient.
Among the present invention, pre-coding matrix obtains by maximization SLNR.This scheme not only can strengthen received signal quality, also suppresses presence of intercell interference, embodiment as shown in Figure 3:
Suppose each cooperate concentrated have B residential quarter, K UE.If all UE receive only single layer data stream, then the reception signal of UE k can be expressed as:
y k = Σ b = 1 B H k , b w b s b + n k - - - ( 1 )
In the formula, y kBe UE K received signal vector, H K, bFor residential quarter b to the complex channel matrix between UE k, measured by down channel by UE; w bFor the pre-coding matrix of residential quarter b, ask for by SLNR; s bBe the descending transmission data of residential quarter b, n kThe expression variance is σ 2Additive white Gaussian noise.
The main plot of UE k is designated as residential quarter a, and for UE k, its received signal power is || H K, aw a|| 2With residential quarter b (b=1,2 ..., among the B, b ≠ a), the UE on the same wireless resource is designated as k with UE k scheduling bWhen then residential quarter a gives the transmission signal of UEk, to UE k bThe interference power that causes is
Figure BDA0000057632580000062
Thereby the SLNR of UEk is:
SLNR k = | | H k , a w a | | 2 Nσ 2 + Σ b = 1 , b ≠ a B | | H k b , a w a | | 2 - - - ( 2 )
Wherein, N is the reception antenna number of UE end.
Obtain the pre-coding matrix of residential quarter a (UE k) by the SLNR of maximization UE k
Figure BDA0000057632580000064
That is:
w a CB =arg max w a ∈ C M × 1 | | H k , a w a | | 2 Nσ 2 + Σ b = 1 , b ≠ a B | | H k b , a w a | | 2 - - - ( 3 )
Wherein, M is the number of transmit antennas of each residential quarter.w a∈ c M * 1Expression w aBe that size is the vector of M * 1.
Formula (3) can be rewritten into:
w a CB =arg max w a ∈ C M × 1 | | H k , a w a | | 2 Nσ 2 + | | H ~ k , a w a | | 2 - - - ( 4 )
In the formula,
Figure BDA0000057632580000073
Be not comprise H K, aThe integration channel matrix, () TThe transposition of representing matrix.
The solution of formula (4) is:
w a CB = max eigenvector ( ( Nσ 2 I + H ~ k , a H H ~ k , a ) + H k , a H H k , a ) - - - ( 5 )
Namely
Figure BDA0000057632580000075
Eigenvalue of maximum characteristic of correspondence vector.In the formula, I represents that size is the unit matrix of M * M, () HThe conjugate transpose of representing matrix, () +The pseudoinverse of representing matrix.
Step 4: scheduling and precoding result are upgraded in certain sequence successively one by one in each residential quarter.The scheduling of all residential quarters and precoding result upgrade and once are considered as iteration one time.Can carry out the one or many iteration.
Each time in the iteration, the target that scheduling result is upgraded is, avoid as far as possible in the neighbor cell, two close UE in geographical position are dispatched on the identical resource.As shown in Figure 4, Fig. 4 a is illustrated in the initial schedule stage (being step 2), and two neighboring edge UE (UE2 and UE 3) that are linked into different districts are scheduled on the identical resource (resource 1, namely Resource 1).Because stronger interference can be brought to UE 3 and UE 2 respectively in residential quarter 1 and residential quarter 2, the service quality of UE 2 and UE 3 is difficult to be guaranteed.By contrast, in iteration each time, because the scheduling of resource result is carried out when upgrading in the residential quarter, will consider the real-time disturbance regime of system.Thereby, avoid UE 2 and UE 3 are dispatched on the identical resource, shown in Fig. 4 b, UE 2 and UE 3 are scheduled for respectively on resource 1 and the resource 2.
The target that the precoding result upgrades is according to the up-to-date scheduling result in each residential quarter, to recomputate the pre-coding matrix of current area.Its calculation criterion is with step 3.Can be seen that by step 3 calculating of pre-coding matrix is not only relevant to the channel matrix of service UE with current area, is decided by that also current area is to the channel matrix of UE that dispatch other residential quarters.And in the iteration scheduling, the scheduling result of each residential quarter can change to some extent, therefore, need recomputate pre-coding matrix according to up-to-date scheduling result.
The presence of intercell interference that the present invention is directed in the cooperative multicast system is effectively coordinated, and can significantly strengthen the service quality of systematic function, particularly Cell Edge User.
Above execution mode only is used for explanation the present invention; and be not limitation of the present invention; the those of ordinary skill in relevant technologies field; under the situation that does not break away from the spirit and scope of the present invention; can also make a variety of changes and modification; therefore all technical schemes that are equal to also belong to category of the present invention, and invention protection range of the present invention should be defined by the claims.

Claims (5)

1. inter-cell interference coordination method that is used for Synergistic multi-point system is characterized in that described method comprises step:
According to the residing geographical position of user, it is divided into joint transmission user and non-joint transmission user;
The initial resource scheduling is carried out independently of one another according to certain criterion in each residential quarter;
Let out according to the initial resource scheduling result of all residential quarters and maximization letter and to make an uproar than criterion, calculate all scheduled users' pre-coding matrix;
Scheduling result and precoding result are upgraded in certain sequence successively one by one in each residential quarter, and the scheduling result of all residential quarters and precoding result upgrade and once be considered as iteration one time, carry out the one or many iteration;
The more fresh target of wherein said scheduling result is, avoid as far as possible in the neighbor cell, two close users in geographical position are dispatched on the identical resource;
Described precoding result's more fresh target is according to the up-to-date scheduling result in each residential quarter, to recomputate the pre-coding matrix of current area.
2. method according to claim 1 is characterized in that, and is described according to the residing geographical position of user, and its step that is divided into joint transmission user and non-joint transmission user is specially:
Cell Edge User classifies as the joint transmission user, and joint transmission user is its transmitting data information by two above residential quarters;
Cell Center User classifies as non-joint transmission user, and non-joint transmission user is its transmitting data information by a residential quarter.
3. method according to claim 1 is characterized in that, the criterion of carrying out described initial resource scheduling comprises: poll, equitable proportion and/or maximization signal interference ratio.
4. method according to claim 1 is characterized in that, described maximization letter is let out and made an uproar than in the criterion:
Described letter is let out the ratio of making an uproar than referring to signal power and leakage power and noise power sum, and wherein, described signal power refers to the signal power that this residential quarter institute dispatched users receives; Described leakage power refers to the interference power sum that this cell downlink transmits other cell schedulings are caused to the user on the same asset; Described noise power is the product of thermal noise and receiving terminal interference coefficient linear domain.
5. according to claim 1 or 4 described methods, it is characterized in that the calculation criterion of pre-coding matrix is that described maximization letter is let out to make an uproar and compared criterion in the described iteration.
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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2013029274A1 (en) * 2011-09-02 2013-03-07 富士通株式会社 Multi-user precoding method and device
CN103068056A (en) * 2012-07-23 2013-04-24 东南大学 Collaboration dispatching and beamforming method based on three-neighborhood collaboration cluster
CN103687035B (en) * 2012-09-03 2017-03-01 工业和信息化部电信传输研究所 The user scheduling method of cooperative multipoint transmission COMP technology
CN104619024B (en) * 2013-11-01 2019-01-04 中国移动通信集团公司 A kind of method, system and the equipment of dynamic cooperative communication
CN105992367B (en) * 2015-03-06 2019-07-12 普天信息技术有限公司 A kind of resource allocation methods for CoMP system
WO2017015802A1 (en) * 2015-07-25 2017-02-02 华为技术有限公司 Method and apparatus for allocating access and backhaul resources
CN107484177B (en) * 2017-08-08 2019-10-22 北京科技大学 A method of realizing heterogeneous network down collaboration multi-point

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101291515A (en) * 2008-06-06 2008-10-22 北京邮电大学 Interference suppressing method in wireless communication system
CN101784103A (en) * 2009-01-19 2010-07-21 大唐移动通信设备有限公司 Method for scheduling users in a plurality of communities and wireless access network equipment thereof
CN101888665A (en) * 2009-05-13 2010-11-17 普天信息技术研究院有限公司 Local scheduler-based multi-point cooperative transmission method

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8427978B2 (en) * 2009-07-16 2013-04-23 Futurewei Technologies, Inc. System and method for information feedback in a wireless communications system with coordinated multiple point transmission

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101291515A (en) * 2008-06-06 2008-10-22 北京邮电大学 Interference suppressing method in wireless communication system
CN101784103A (en) * 2009-01-19 2010-07-21 大唐移动通信设备有限公司 Method for scheduling users in a plurality of communities and wireless access network equipment thereof
CN101888665A (en) * 2009-05-13 2010-11-17 普天信息技术研究院有限公司 Local scheduler-based multi-point cooperative transmission method

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
《A Leakage-Based Precoding Scheme for Downlink Multi-User MIMO Channels》;Mirette Sadek;《IEEE Xplore》;20070531;第1713页，1715页 *
Mirette Sadek.《A Leakage-Based Precoding Scheme for Downlink Multi-User MIMO Channels》.《IEEE Xplore》.2007,

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