CN103648112A - Method for converting opening/closing state of base stations in micro cell in cellular network - Google Patents

Abstract

The invention relates to a method for scheduling opening or closing of base stations by a wireless resource manager according to system performance gains of the base station under different states (opening/closing) under the micro cell scene in a cellular network. The method includes that step1 the wireless resource manager transmits a down signal to open the base stations and transmits a finding signal to close the base stations to acquire channel information between the base stations and users, and the wireless resource manager schedules the information; step2 the wireless resource manager starts to calculate the performance of each base station under different states once the conditions are triggered; step3 the optimum closing or opening state of the base stations is scheduled according to effects of different states of the base stations on the system performance. By means of flexible scheduling of the states of the base stations, selection of each state of the base stations enables the performance gains to be maximum, and the whole system performance is improved accordingly.

Description

A kind of method of small-cell base station On/Off state conversion in cellular network

Technical field

What the present invention relates to is a kind of method of wireless communication technology field, specifically a kind of cellular network in, under the scene of small-cell, the performance gain that radio resource manager obtains under different conditions (On/Off) according to each base station, thereby obtain a kind of method of dispatching base station state, obtain the raising of systematic function.

Background technology

Along with the development of mobile wireless cellular network communication technology, a large amount of uses of intelligent terminal, people grow with each passing day for the demand of the transmission rate of cellular communication.In order to meet the growing rate requirement of people, the technology of wireless cellular network is ceaselessly in development.China has strengthened the supporting dynamics for cellular network in recent years, produced thus have independent intellectual property right the third generations such as TD-SCDMA, TD-LTE, the 4th generation mobile cellular network technology.3GPP is organized in following mobile cellular network technology standardization process, and small-cell scene has been shown to great concern.

Small-cell is lower powered radio access node, is operated in frequency spectrum mandate, unauthorized, can cover the scope of 10 meters to 200 meters, and by contrast, the coverage of macrocellular can reach several kilometers.Mobile operator is anxious for the data traffic increasing, and a lot of operators think that shunting Mobile data is the good method of effective use radio spectrum resources.Therefore they think that small-cell deployment scheme is the effective way of management LTE-A frequency spectrum, and just do not use macrocellular.It has merged Home eNodeB, picocell, Microcell and distributed wireless technology, as RRH.

In order to meet increasing data demand, the distance that shortens base station and terminal becomes the boosting power that small-cell scene is disposed, yet along with a large amount of deployment base station, causes the interference between base station to become one of subject matter under the scene of small-cell.

The method of an efficient scheduling base station state has been proposed in the present invention.Compare the state of base station standard-sized sheet, the present invention can improve systematic function effectively, and guarantees that the scheduling of each step base station state is all optimum.

Summary of the invention

The object of the invention is for there being small-cell deployment scenario, provide a kind of under the scene of small-cell the method for efficient scheduling cell status.A kind of method that specifically in cellular network, small-cell base station On/Off state is changed.

The present invention for achieving the above object, adopts following technical scheme:

First the state that we provide base station is closed from being opened to, and mainly comprises following step:

Step 1: the base station of unlatching sends reference signal downwards, the base station of closing is to issuing discovery signals, and user is according to these signals, and feedback channel situation is to base station.The base station that note is opened integrates as B, and the base station of closing integrates as C.Radio resource manager obtains channel conditions.

Step 2: certain base station number of user equipment detected and be less than λ _thor the mean data rate that certain community detected is lower than threshold value R _th.If do not met, use unlatching to integrate base station in B and serve as user, jump to step 1.

Step 3: first, calculate and open the total throughput in collection B small area, be designated as T;

Step 4: secondly, calculate each community in unlatching collection B and close situation.Suppose to select community j to close, the user of community j selects a B to concentrate the community access of channel maximum in residue base station, upgrades unlatching collection and closure set here, B ^new=B { j} and C ^new{ j} represents that B concentrates minimizing community j and C to concentrate and increases community j to=C ∪.Calculate again B ^newconcentrate the total throughput in community to be designated as

thereby the throughput before drawing the throughput of hypothesis j community after closing and closing is only poor, is designated as Δ T _j, so

Step 5: select max{ Δ T _j, return to maximum Δ T _maxwith community indication m.If Δ T _maxbe greater than zero, execution step 6.Otherwise integrate B by unlatching, as user, serve, jump to step 1.

Step 6: select community m to close, upgrade cell set B ^new=B { j} and C ^new=C ∪ { j}.Jump to step 3.

Preferably, described step 1 comprises as follows:

Downlink reference signal is sent out in each base station, and user feeds back to base station after measuring, and radio resource manager is passed to by information in base station, thereby obtains following parameter, and j base station i the user's in Dao Zhe community channel gain is designated as H _i,j, other k base station is designated as H to i user's channel _i,k, suppose that base station all sends with identical power, is designated as P _j=P _k=P, wherein user ID i ∈ U _j, the user of j community of expression.The base station that note is opened integrates as B, and the base station of closing integrates as C.

Preferably, described step 3 comprises as follows:

Step 3.1: radio resource manager calculates opens the total throughput in state Xia community that in collection B, is opening each base station:

Remember the throughput of j base station $T_j=\underset{i\∈U_j}{\mathrm{\Σ}}{\log }_2(1+{\mathrm{SINR}}_{i,j})$

Wherein

represent signal and interference and noise ratio that user i receives, N ₀represent noise;

Step 3.2: the throughput of Zong community is: $T=\underset{j\∈B}{\mathrm{\Σ}}\underset{i\∈U_j}{\mathrm{\Σ}}{\log }_2(1+{\mathrm{SINR}}_{i,j}).$

Preferably, described step 4 comprises as follows:

Step 4.1: the user of the inside, j community transfers to B and concentrates the inside, channel quality Hao community, upgrades B ^new=B { j} and C ^new=C ∪ { j}, B ^newin the user collection of k community be updated to

Step 4.2: according to step 4.1, then calculate B ^newconcentrate total throughput, note B ^newconcentrate the throughput of k community $T_k=\underset{i\∈U_k^{\mathrm{new}}}{\mathrm{\Σ}}{\log }_2(1+{\mathrm{SINR}}_{i,k}^{\mathrm{new}});$ Wherein ${\mathrm{SINR}}_{i,k}^{\mathrm{new}}=\frac{P_k{H}_{i,k}}{\underset{\underset{1\∈B^{\mathrm{new}}}{1\≠k}}{\mathrm{\Σ}}{P}_1{H}_{i,1}+N_0},$ Represent under the collection of new base station the signal that user i receives and interference and noise ratio, N ₀represent noise;

Step 4.3: the throughput of Zong community is: $T_j^{\mathrm{off}}=\underset{k\∈B^{\mathrm{new}}}{\mathrm{\Σ}}\underset{i\∈U_k^{\mathrm{new}}}{\mathrm{\Σ}}{\log }_2(1+{\mathrm{SINR}}_{i,k}^{\mathrm{new}});$

Step 4.4: can calculate according to step 3.2 and step 4.3

Next provides base station state from being closed to unlatching, mainly comprises following step:

Step 1: the step 1 of closing is identical with being opened to, and radio resource manager obtains channel conditions.

Step 2: number of user equipment is more than δ in base station being detected _thor user finds have base station to be greater than γ with the value of its place cell channel on its channel ratio in closure set C _th.If do not met, use unlatching to integrate base station in B and serve as user, jump to step 1.

Step 3: the step 3 of closing is identical with being opened to, calculates and opens the total throughput in collection B small area, is designated as T.

Step 4: select Yi Ge community in closure set C to open at every turn, suppose to select community j to open, channel ratio and place cell channel quality between user and j community are good, and user accesses j community.Upgrade B ^new=B ∪ { j} and C ^new=C { j}.Calculate again B ^newconcentrate the total throughput in community to be designated as

thereby the throughput before drawing throughput after open hypothesis different districts and closing is only poor, is designated as Δ T _j.

Step 5: select max{ Δ T _j, return to maximum Δ T _maxwith community indication m.If Δ T _maxbe greater than zero, perform step 6; Otherwise integrate B by unlatching, as user, serve, jump to step 1.

Step 6: select community m to open, upgrade cell set B ^new=B ∪ { j} and C ^new=C { j} jumps to step 3.

In step 4:

in being opened to and closing

computational methods are the same, Δ T _jcomputational methods also with to be opened to the computational methods of closing the same.

In step 5, the computational methods of return value are with to be opened to the computational methods of closing the same.

Compared with prior art, the present invention has following beneficial effect:

(1) in the present invention, radio resource manager calculates according to the impact on systematic function under different conditions of each base station, a base station selected state that makes performance gain maximum.Thereby guarantee the raising of entire throughput.

(2) in the present invention, base station is according to maximum gain, and efficient scheduling base station is opened and still closed, absolute gain that can guaranteed performance, and iteration is each time all local optimum, the base station state of having avoided choosing can make the situation of degradation.

(3) in the present invention, radio resource manager can walk the raising that optimum scheduling base station state obtains throughput by each.

Accompanying drawing explanation

Fig. 1 is that base station is from being opened to the flow process of closing.

Fig. 2 is that base station is from being closed to the flow process of unlatching.

Embodiment

As Fig. 1, below in conjunction with specific embodiment, the present invention is described in detail.Following examples will contribute to those skilled in the art further to understand the present invention, but not limit in any form the present invention.It should be pointed out that to those skilled in the art, without departing from the inventive concept of the premise, can also make some distortion and improvement.These all belong to protection scope of the present invention.

As shown in Figure 1, 2, the present invention be a kind of cellular network in, under the scene of small-cell, the performance gain that radio resource manager obtains under different conditions (On/Off) according to each base station, thereby obtain a kind of method of dispatching base station state, increase throughput of system.Key step is: open base station send out downstream signal and close that base station sends out that discovery signals is used for obtaining and user between channel information, radio resource manager is dispatched these information.Once trigger condition, radio resource manager starts to calculate each base station systematic function under different conditions.Impact according to the different state in base station on systematic function, the strategy of closing or opening of scheduling base station the best, effectively improves throughput of system.

Specific implementation step comprises following steps:

The first step, supposes to have 1 macro base station here, ensuring coverage.6 small-cell base stations, wherein 4 is to open base station, 2 is to close base station.Macro base station and small-cell base station alien frequencies are disposed, between do not disturb.Opening the number of users of altogether serving base station is 20, opens base station and sends out downlink reference signal to user, closes base station and sends discovery signals downwards, and user, according to these signals, feeds back to BTS channel information.B={1，2，4，5}，C={3，6}；

Second step, radio resource manager detects that in the base station of unlatching, to have the number of users of 1 base station service be 1 to be less than 2.

The 3rd step, first calculates B and concentrates total throughput to be

b={1 wherein, 2,4,5}.Then start to calculate B centralized base-station and when closing, bring respectively the throughput gain of system, circulation for the first time, B ^newand C ^newcomprise respectively 4 kinds of set, as base station 1, B while closing ^new={ 2,4,5} and C ^new={ 1,3,6}, the now discovery of the user in base station 1 is best with the channel of base station 4, selects to be linked into base station 4.Calculate B ^newthroughput during collection $T_j^{\mathrm{off}}=\underset{k\∈B^{\mathrm{new}}}{\mathrm{\Σ}}\underset{i\∈U_k^{\mathrm{new}}}{\mathrm{\Σ}}{\log }_2(1+{\mathrm{SINR}}_{i,k}^{\mathrm{new}}),$ Calculated gains obtains $\mathrm{\Δ}{T}_1=T_1^{\mathrm{off}}-T,$ Other situation criterions are the same.The gain of radio resource manager obtains respectively different base station while closing throughput of system, relatively show when the 4th base station closed, performance benefits is maximum, closes the 4th.

The 4th step, upgrades and now opens base station, has B={1, and open 2,5} base station, C={3, and 4,6} closes base station.Execution step three, circulation for the second time, concentrate to continue selects base station to close from B, finds that the 5th base station benefits maximum but be negative value, and end circulates.Use and open collection B={1,2,5} is user's service.

The 5th step, opens base station collection B={1,2,5} and closure set C={3, and 4,6}, opens base station and sends out downlink reference signal to user, closes base station and sends discovery signals downwards, and user, according to these signals, feeds back to BTS channel information.

The 6th step, the number of users that radio resource manager detects Zhong Youge base station, the base station service of unlatching be 8 more than 7.

The 7th step, the throughput while first calculating B collection, method is identical with step 3.Start to calculate C centralized base-station and when opening, bring respectively the throughput gain of system, circulation for the first time, B ^newand C ^newcomprise respectively 3 kinds of set, as B ^new={ 1,2,5,6} and C ^new=1,3}, and now by the channel quality between service-user and the 6th base station than and base station, place between the good user of channel quality be switched in the 6th base station, calculated performance gains to such an extent that method is identical with step 3, other situation criterions are the same.When radio resource manager obtains respectively different base station unlatching, the gain of throughput of system, relatively draws when the 3rd base station closed, and performance benefits is maximum, opens the 3rd.

The 8th step, upgrades and now opens base station, has B={1, and open 2,3,5} base station, C={4, and 6} closes base station.Execution step seven, circulation for the second time, concentrate to select base station to open from C, finds that the 4th base station benefits maximum but be negative value, and end circulates.Use and open collection B={1,2,3,5} is user's service.

Claims (4)

1. in cellular network, small-cell base station, from being opened to a method of closing, comprises the steps:

Step 1: the base station of unlatching sends reference signal downwards, the base station of closing sends discovery signals downwards, and user is according to these signals, and feedback channel situation is to base station; The base station that note is opened integrates as B, and the base station of closing integrates as C; Radio resource manager obtains channel conditions;

Step 2: certain base station number of user equipment detected and be less than λ _thor the mean data rate that certain community detected is lower than threshold value R _thif, do not meet, use unlatching to integrate base station in B and serve as user, jump to step 1;

Step 3: calculate and open the total throughput in collection B small area, be designated as T;

Step 4: calculate each community in unlatching collection B and close situation: suppose to select community j to close, the user of community j selects a B to concentrate the community of channel maximum in residue base station to access, and upgrades unlatching collection and closure set here, B ^new=B { j} and C ^new{ j}, represents that B concentrates minimizing community j and C to concentrate and increases community j to=C ∪; Calculate again B ^newconcentrate the total throughput in community to be designated as thereby the throughput before drawing the throughput of hypothesis j community after closing and closing is only poor, is designated as Δ T _j, so

Step 5: select max{ Δ T _j, return to maximum Δ T _maxwith community indication m; If Δ T _maxbe greater than zero, execution step 6; Otherwise integrate B by unlatching, as user, serve, jump to step 1;

Step 6: select community m to close, upgrade cell set B ^new=B { j} and C ^new=C ∪ { j}; Jump to step 3.

In cellular network according to claim 1 small-cell base station from being opened to the method for closing, it is characterized in that, described step 1 comprises as follows: downlink reference signal is sent out in each base station, user feeds back to base station after measuring, radio resource manager is passed to by information in base station, thereby obtain following parameter, j base station i the user's in Dao Zhe community channel gain is designated as H _i,j, other k base station is designated as H to i user's channel _i,k, suppose that base station all sends with identical power, is designated as P _j=P _k=P, wherein user ID i ∈ U _j, the user of j community of expression; The base station that note is opened integrates as B, and the base station of closing integrates as C.

The calculation procedure of described step 3 small area throughput is as follows:

Step 3.1: radio resource manager calculates opens the total throughput in state Xia community that in collection B, is opening each base station:

Remember the throughput of j base station $T_j=\underset{i\∈U_j}{\mathrm{\Σ}}{\log }_2(1+{\mathrm{SINR}}_{i,j})$

Wherein

represent signal and interference and noise ratio that user i receives, N ₀represent noise;

Step 3.2: the throughput of Zong community is: $T=\underset{j\∈B}{\mathrm{\Σ}}\underset{i\∈U_j}{\mathrm{\Σ}}{\log }_2(1+{\mathrm{SINR}}_{i,j}).$

Described step 4 comprises as follows:

Step 4.1: the user of the inside, j community transfers to B and concentrates the inside, channel quality Hao community, upgrades B ^new=B { j} and C ^new=C ∪ { j}, B ^newin the user collection of k community be updated to

Step 4.2: according to step 4.1, then calculate Bnew and concentrate total throughput, note Bnew concentrates the throughput of k community $T_k=\underset{i\∈U_k^{\mathrm{new}}}{\mathrm{\Σ}}{\log }_2(1+{\mathrm{SINR}}_{i,k}^{\mathrm{new}});$

Wherein

represent under the collection of new base station the signal that user i receives and interference and noise ratio, N ₀represent noise;

Step 4.3: the throughput of Zong community is: $T_j^{\mathrm{off}}=\underset{k\∈B^{\mathrm{new}}}{\mathrm{\Σ}}\underset{i\∈U_k^{\mathrm{new}}}{\mathrm{\Σ}}{\log }_2(1+{\mathrm{SINR}}_{i,k}^{\mathrm{new}});$

Step 4.4: can calculate according to step 3.2 and step 4.3

3. in cellular network, small-cell base station, from being closed to a method for unlatching, comprises the steps:

Step 1: the base station of unlatching sends reference signal downwards, the base station of closing sends discovery signals downwards, and user is according to these signals, and feedback channel situation is to base station; The base station that note is opened integrates as B, and the base station of closing integrates as C; Radio resource manager obtains channel conditions;

Step 2: number of user equipment is more than δ in base station being detected _thor user finds have base station to be greater than γ with the value of its place cell channel on its channel ratio in closure set C _th; If do not met, use unlatching to integrate base station in B and serve as user, jump to step 1;

Step 3: calculate and open the total throughput in collection B small area, be designated as T;

Step 4: select Yi Ge community in closure set C to open at every turn, suppose to select community j to open, channel ratio and place cell channel quality between user and j community are good, and user accesses j community; Upgrade B ^new=B ∪ { j} and C ^new=C { j}; Calculate again B ^newconcentrate the total throughput in community to be designated as

thereby the throughput before drawing throughput after open hypothesis different districts and closing is only poor, is designated as Δ T _j; So $\mathrm{\Δ}{T}_j=T_j^{\mathrm{on}}-T;$

Step 5: select max{ Δ T _j, return to maximum Δ T _maxwith community indication m.If Δ T _maxbe greater than zero, perform step 6; Otherwise integrate B by unlatching, as user, serve, jump to step 1;

Step 6: select community m to open, upgrade cell set B ^new=B ∪ { j} and C ^new=C { j} jumps to step 3.

4. in cellular network according to claim 3, small-cell base station, from being closed to the method for unlatching, is characterized in that:

The calculation procedure of described step 3 small area throughput is as follows:

Step 3.1: radio resource manager calculates opens the total throughput in state Xia community that in collection B, is opening each base station:

Remember the throughput of j base station $T_j=\underset{i\∈U_j}{\mathrm{\Σ}}{\log }_2(1+{\mathrm{SINR}}_{i,j})$

Wherein

represent signal and interference and noise ratio that user i receives, N ₀represent noise;

Step 3.2: the throughput of Zong community is: $T=\underset{j\∈B}{\mathrm{\Σ}}\underset{i\∈U_j}{\mathrm{\Σ}}{\log }_2(1+{\mathrm{SINR}}_{i,j}).$

Described step 4 comprises as follows:

Step 4.1: select community j to open from closure set C, channel ratio and place cell channel quality between user and j community are good, and user accesses j community.Upgrade B ^new=B ∪ { j} and C ^new=C { j}, B ^newin the user collection of k community be updated to

Step 4.2: according to step 4.1, then calculate B ^newconcentrate total throughput, note B ^newconcentrate the throughput of k community $T_k=\underset{i\∈U_k^{\mathrm{new}}}{\mathrm{\Σ}}{\log }_2(1+{\mathrm{SINR}}_{i,k}^{\mathrm{new}});$

Wherein

represent under the collection of new base station the signal that user i receives and interference and noise ratio, N ₀represent noise;

Step 4.3: the throughput of Zong community is: $T_j^{\mathrm{off}}=\underset{k\∈B^{\mathrm{new}}}{\mathrm{\Σ}}\underset{i\∈U_k^{\mathrm{new}}}{\mathrm{\Σ}}{\log }_2(1+{\mathrm{SINR}}_{i,k}^{\mathrm{new}});$ Step 4.4: can calculate according to step 3.2 and step 4.3

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