CN102149137B - Cell access control method - Google Patents

Abstract

The invention discloses a cell access control method, relating to the technical field of mobile communication. The method comprises the following steps: S1, each PeNB (Pico evolved Node B) periodically obtains partial parameters of a neighbor base station; S2, each PeNB calculates an offset of the base station on an access threshold according to the updated parameter of the neighbor base station;S3, each PeNB broadcasts the offset of the base station to a user in the form of pilot frequency; S4, the user corrects a base station receiving power through overlapping the offset of the base station on a pilot frequency power of the base station to finish cell selection. The scheme of the invention can effectively balance loads of a hotspot overlay network, increases the edge spectrum utilization rate of the system and has the advantages of low complexity and stronger practicability.

Description

Community access control method

Technical field

The present invention relates to the mobile communication technology field, relate in particular to a kind of community access control method of outdoor focus overlay network.

Background technology

The 5D working group (WP5D) of international telecommunication Electricity Federation-wireless department (ITU-R) sends circular along with in January, 2008, collect the air interface technologies (RIT) of the 4th third-generation mobile communication system (IMT-Advanced), the competition of new round mobile communication standard and fusion beginning.IMT-Advanced has proposed higher technical need, reaches 7.5bps/Hz and 15bps/Hz respectively as the peaks spectrum efficient of up-downgoing, and require to support up to the bandwidth more than the 40MHz etc.In order to satisfy the demand of IMT-Advanced, improve constantly power system capacity and the service quality of radio communication, the multiple-input, multiple-output of enhancing (MIMO), carrier aggregation (CA), isomery are disposed multinomial key technologies such as (HetNet) and are emerged in large numbers in succession.

The isomery on-premise network will become one of main mode of future network deployment.The isomery on-premise network is on the basis that the legacy cellular macro base station covers, by increasing the network that new network node guarantees to cover, improve systematic function.On the one hand, well-known, in the high band communication, the radio wave propagation, under the influence of various factorss such as path loss, shadow fading, multipath interference, it is faster to decline, propagation distance is limited, and isomery is disposed and will be helped to remedy various covering blind spots, improves marginal user performance.On the other hand, investigation shows that will there be stronger concentration the spot of next generation wireless communication business, as indoor focuses such as office spaces, or outdoor focus such as shopping mall.The high speed data transmission service demand of hot zones also will effectively promote the increase that focus covers.According to the definition in the Long Term Evolution (3GPP LTE) of third generation partner program, isomery can be disposed and be divided into four types: relaying, distributed system (also being that radio frequency zooms out), focus cover and Home eNodeB.The know-why of different deployment types with towards deployment scenario difference to some extent.

Wherein, what the Home eNodeB covering was primarily aimed at is indoor covering and its a part of outdoor covering of booking reader, and the deployment of Home eNodeB has stronger not intellectual and randomness.By contrast, the siting of station that focus covers is normally finished by operator, towards near all indoor and outdoors users.Some research work show that the focus of this open access covers compares the coverage mode that limited subscriber inserts, and can obtain better system performance.It is to be noted, focus covers newly-increased microcell base station (Pico evolved Node B, PeNB, also abbreviate little base station as), be interface and traditional macrocell base stations (the Macro evolvedNode B by pre-defining, MeNB also abbreviates macro base station as) connect, interface specification observed.

In open focus covered, the user not only can be linked into MeNB, also can be linked in the middle of the PeNB.Under such background, (Cell Selection CS) will become an important problem to the selection of user residential quarter.Be mainly reflected in following two aspects:

One, the randomness of network causes the interference environment complexity.

The deployment that focus covers has stronger unpredictability.The development in certain area, user density increase, and make that at any time setting up a new PeNB becomes possibility.In the deployment that focus covers, to a certain extent, the quantity of PeNB, configuration parameter (power, antenna height etc.) and geographical position are that the character by hot zones determines.Generally, these attributes all have certain randomness.Therefore, the disturbed condition of focus covering is more more complicated than conventional cellular cell.Especially when an area newly-increased deployment occurs or closes existing deployment, these variations will produce a very large impact macro base station and near PeNB network environment, the choice of the edge customer under especially each covers.Pull one hair and move the whole body, the load balancing of whole network will once be adjusted dynamically.The hardware device that PeNB disposes is nonadjustable as position, power amplifier etc.The soft configurations such as method of having only Access Control Policy and resource to distribute that can adjust.

Its two, highdensity focus base station makes the inhomogeneous possibility of user distribution increase.

Traditional access control algorithm is by the maximum principle of large scale gain mostly, as the maximum base station (eNB) of direct selection large scale gain, or in the maximum several eNB that gain, select at random etc.Because the transmitted power of PeNB is (original intention of 3GPP design PeNB is exactly the newly-increased network node of low-power consumption) with certain upper limit, is distributed in the user that PeNB covers the edge, according to the maximum principle of large scale gain, will insert MeNB with bigger probability.Number of users in PeNB covers is (such as when user=2/3 of PeNB user/always) more for a long time, studies show that, the number of users of PeNB active service is much smaller than expection, also is that the edge customer of many PeNB overlay area is all discharged by PeNB and given MeNB.This can cause contention MeNB resource user quantity more, with having influence on the performance of MeNB user and even whole area of coverage intra domain user, as network throughput, edge customer throughput etc.

Therefore, when design PeNB, not only to consider the size of the original maximum transmit power of PeNB, more will consider when the inhomogeneous degree of user distribution increases, how dynamically to adjust the load that access strategy comes balance PeNB and MeNB.

In sum, at the focus overlay network, design a rational community access control method, take into full account above factor of overall importance, when guaranteeing that focus covers the central user performance, deal carefully with the access base station of edge customer, the performance of balance MeNB and PeNB, center of housing estate and cell edge is fully excavated the performance potential of network, improves effective utilization rate of resource, increase user satisfaction, become a major issue that needs to be resolved hurrily.

Summary of the invention

(1) technical problem that will solve

The technical problem to be solved in the present invention provides a kind of community access control method that is suitable for outdoor focus overlay network, can reach balancing network load effectively, improves the system edges availability of frequency spectrum, complexity is low, has stronger practicality.

(2) technical scheme

For solving the problems of the technologies described above, the invention provides a kind of community access control method, may further comprise the steps:

S1, each the little base station PeNB that is arranged in the residential quarter obtains the parameter of adjacent base station periodically;

S2, each PeNB be according to the parameter of the adjacent base station that obtains, and according to this base station of described calculation of parameter in the side-play amount that inserts on the thresholding;

S3, each PeNB is broadcast to the user with the side-play amount of this base station with the form of pilot tone;

S4, the user is superimposed upon on the pilot power of PeNB by the side-play amount of each PeNB that will receive, thereby the received power of PeNB is revised, and finishes the residential quarter and selects.

Wherein, described residential quarter is arranged in the focus overlay network, and each described residential quarter comprises a macro base station MeNB and some PeNB, and described adjacent base station is MeNB or PeNB.PeNB is the network element with complete Radio Resource control function, inserts backbone network by wired connection.Each PeNB carries out information interaction by adjacent with other PeNB with MeNB of interface of systemic presupposition.Each MeNB or PeNB carry out information interaction by interface and the upper level network element of systemic presupposition.

Wherein, PeNB uses omnidirectional antenna, and macro base station MeNB uses fan antenna or omnidirectional antenna.

Wherein, the mode of PeNB acquisition parameter is among the step S1: adjacent base station directly transmits parameter by interface, and perhaps, other base station or upper level network element are by the interface retransmitting paramater.

Wherein, among the step S1, the parameter that each PeNB obtains comprises: the geographical position of base station, transmitted power; The base station is to the channel large scale fading factor of this PeNB.

Wherein, among the step S1, set in advance the cycle that each PeNB obtains the parameter of adjacent base station according to network environment, and for geographical position, the transmitted power of base station, it is mutual only to carry out primary information, or initiates mutual according to request; For the channel large scale fading factor of base station to this PeNB, the mutual cycle is more than or equal to hundred Milliseconds.

Wherein, the method of calculating side-play amount among the step S2 is subjected to adjacent base station by PeNB and disturbs stack level afterwards to determine that (each adjacent base station can form an interference region (also namely receiving SIR less than the zone of default thresholding) to this PeNB, the form of these zones with set stacked up, the zone gross area occupies the size of this PeNB area coverage, be exactly that this PeNB is subjected to adjacent base station interference stack " level " afterwards), specifically calculate according to following steps:

1. define user's reception signal interference ratio SIR thresholding λ _Th, as weighing the separation whether user can accept base station normal service level;

2. to current PeNB, select an one adjacent base station, only under the influence of this adjacent base station, user SIR thresholding is less than λ in the current PeNB coverage in calculating _ThInterference region; This zone is in the marginal position of PeNB overlay area usually;

3. select other adjacent base station of described current PeNB successively, calculate the only described interference region under the influence of selected adjacent base station, each interference region is asked union according to the mode of set, as total interference region of current PeNB; Total interference region is distributed in the marginal position that current PeNB covers;

4. occupy the size of current PeNB area coverage according to total interference region, calculate current PeNB access control side-play amount;

5. with constant of gained side-play amount stack, as the result of calculation of side-play amount.

Wherein, calculate the interference region when and if only if exists an adjacent base station, be divided into two classes:

1. when adjacent base station is the macro base station MeNB of use fan antenna, calculate by computer software;

2. when adjacent base station is omnidirectional antenna, calculate by closed solutions.

Wherein, the step process of calculating the access control side-play amount by total interference region in 4. comprises the steps:

Suppose that ideally total interference region is an annular section of current PeNB coverage edge, according to the area of total interference region, try to achieve the width of this annular section; Only serving annular section with current PeNB then is target with interior user, dwindles the covering radius of current PeNB, and improves the threshold value of access power, obtains corresponding access control side-play amount thus.

Wherein, step 5. in employed constant pre-defined by network terminal, and for all PeNB, this constant is consistent.

(3) beneficial effect

Compared with prior art, the present invention can produce following beneficial effect: the present invention is by analyzing the disturbed condition that different PeNB are subjected to, for it designs different access control side-play amounts, in selecting, the residential quarter takes into full account the concrete environment of each PeNB, therefore can under the prerequisite that keeps system's average frequency spectrum utilance, improve the data rate of edge customer effectively, make offered load more balanced, and computational complexity is low, has stronger practicality.

Description of drawings

Fig. 1 is total interference region schematic diagram that each PeNB of the embodiment of the invention is subjected to;

Fig. 2 is the interference region schematic diagram when interference base station is the MeNB sector of the embodiment of the invention;

Fig. 3 is the interference region schematic diagram when interference base station is the omnidirectional antenna base station of the embodiment of the invention;

Fig. 4 is the method flow diagram of the embodiment of the invention;

Fig. 5 is the method sequential chart of the embodiment of the invention;

Fig. 6 is that the method for the embodiment of the invention compares schematic diagram with user's large scale distribution of other typical method under 4 PeNB situations of every sector deployment;

Fig. 7 is that the method for the embodiment of the invention inserts the PeNB ratio than schematic diagram with the user of other typical method under 4 PeNB situations of every sector deployment;

Fig. 8 is that the method for the embodiment of the invention inserts the PeNB ratio than schematic diagram with the user of other typical method under 10 PeNB situations of every sector deployment;

Fig. 9 is that the method for the embodiment of the invention and the residential quarter average frequency spectrum utilance of other typical method compare schematic diagram;

Figure 10 is that the method for the embodiment of the invention and the cell edge availability of frequency spectrum of other typical method compare schematic diagram.

Embodiment

Below in conjunction with drawings and Examples, the specific embodiment of the present invention is described in further detail.Following examples are used for explanation the present invention, but are not used for limiting the scope of the invention.

Suppose that a center of housing estate has 3 macro base station MeNB, fan antenna has been installed respectively, be responsible for the covering of 120 degree scopes.There is N the focus base station PeNB that omnidirectional antenna has been installed in the zone of each MeNB, and parameters such as the position of each PeNB have certain randomness.For PeNB i, its covering radius is r _i, i=1,2 ... N.Under the prerequisite of only considering the large scale decline, for user in any one zone, it receives MeNB m and PeNB i pilot signal power can be expressed as respectively:

P _r，i＝P _p-a _i-b _plogd _i，(2)

Wherein, for MeNB m, P _mThe expression transmitted power, b _mThe expression user is to the path loss factor of MeNB, a _mThe expression user is to other large scale decline parameter (as shadow fading and other constant) of MeNB, d _mRepresent the user to the distance of MeNB,

The antenna mode gain of expression MeNB.Here only consider the horizontal gain of antenna.Similarly, for PeNB i, b _pThe expression user is to the path loss factor of PeNB, a _iThe expression user is to other large scale decline parameter (as shadow fading and other constant) of PeNB, d _mThe expression user only considers the situation of the transmitted power equalization of each PeNB here to the distance of PeNB, and its size is P _p

For each PeNB i, designed side-play amount β _i, represented by following formula:

β _i＝β _c+β _i，d. (3)

Wherein, β _cValue for all PeNB is consistent, is arranged and is adjusted by network terminal.β _{I, d}The difference that then reflects different PeNB side-play amounts, this difference are to be determined by the disturbed condition that each PeNB is subjected to.

In the residential quarter was selected, intuitively, if the base station of a high capacity is selected to insert certain user, after this user that must be that and if only if so inserted, its minimum essential requirement still can be satisfied by the resource of this base station.Otherwise, then should not insert this user.Usually, controversial like this user often is in the edge that the base station covers.The user that demand can not be met after those access base stations inserts, and this base station can insert thresholding by improving, reduce the overlay area realizes.

Defining such covering border district is interference region (IR): when the user is in this zone, inserts this base station and will cause user's average received signal interference ratio (SIR) can not satisfy a default thresholding λ _ThRequirement.In order to set up IR and designed side-play amount β _iRelation, IR is assumed to be a desirable regular annular section, shown in accompanying drawing 1 left-half, and think that this annular section is the result that whole zone is subjected to other interference base station comprehensive function.The β that proposes _iWidth Delta r with annulus _{I, I}Be closely-related.Therefore, should at first try to achieve the area of annulus, be designated as δ _i

In real network, the quantity of interference source is limited, shown in accompanying drawing 1 right half part.Actual IR will be an areas with irregular.In order to calculate the area of actual IR, suppose that at first ideally the area of annulus is consistent with irregular IR area in the real network.So problem is converted into finds the solution irregular IR area in the real network.

Being the area of IR in the realistic internet, also is desirable area δ _iValue, be several mutual incoherent subdivisions with this irregular IR Region Decomposition.Each part, η _{I, j}, expression ought only have an interference base station j, when i ≠ j exists, and the IR of PeNB i.Definition S (η _{I, j}) be regional η _{I, j}Area.Finally, the area that defines whole irregular IR is the area in the union zone of each mutual incoherent subdivision IR, is expressed as:

${\mathrm{\δ}}_i=S\left(\underset{j=0,j\≠i}{\overset{N}{\∪}}{\mathrm{\η}}_{i,j}\right).---\left(4\right)$

So far, problem is converted into when target P eNB has only an adjacent interference base station, how to obtain the IR of target P eNB.Specifically be divided into the situation that interference base station is MeNB and PeNB again.

1. interference base station is MeNB

For PeNB i, when having only one to disturb MeNB m, UE inserts PeNB i and SIR does not satisfy threshold requirement λ _ThCondition can be expressed as:

P _r，i-P _r，m≤λ _th. (5)

Formula (1) and (2) are updated to formula (5), obtain:

Wherein, λ ' _Th=P _p-P _m-(a _i-a _m)-λ _ThIsomery with reference to 3GPP LTE is disposed channel model, b _i=36.7, b _m=37.6, suppose b here _i=b _m=b,

Be defined as

A _m＝25dB，(7)

Wherein,

Be the user to the direct-view footpath of base station and the angle of antenna for base station main lobe direction, As shown in Figure 2.

As shown in Figure 2, the coordinate of two eNB is respectively (0,0) and (p _x, p _y), the antenna main lobe direction of MeNB is the direction along the x axle.If the position of UE be (x, y).Then the distance of UE to two eNB has following relation:

$d_m^2=x^2+y^2,d_i^2={(x-p_x)}^2+{(y-p_y)}^2.---\left(8\right)$

When

The time, through deriving, the zone of formula (6) representative can be expressed as:

This is a transcendental inequality, and its feasible zone can't obtain by the mode of closed solutions.Therefore, select to estimate by computer software (as Matlab).

When

Similarly, can obtain:

Say hereinafter to show that this zone is a sector region.So far, η _{I, m}Can be in the hope of being:

${\mathrm{\η}}_{i,m}=(P_1\∪P_2)\∩\left\{(x,y)\right|x^2+y^2\≤r_i^2\}.---\left(11\right)$

2. interference base station is PeNB

For PeNB i, when having only an interference base station PeNB j, during j ≠ i, UE inserts PeNBi and SIR does not satisfy threshold requirement λ _ThCondition can be expressed as:

$P_{r,i}-P_{r,j}=(P_p-P_m)-(a_i-a_m)-b_p\log \frac{d_i}{d_j}\≤{\mathrm{\λ}}_{\mathrm{th}},---\left(12\right)$

Formula (12) can further be converted into:

$\frac{d_i^2}{d_j^2}\≥{10}^{\frac{2}{b_p}[(P_p-P_m)-(a_i-a_m)-{\mathrm{\λ}}_{\mathrm{th}}]}={\mathrm{\λ}}_{\mathrm{th}}^{\′\′}.---\left(13\right)$

As shown in Figure 3, the coordinate of two eNB is respectively (0,0) and (d, 0).If the position of UE be (x, y), then the zone of formula (13) representative can be expressed as:

$P=\left\{\begin{array}{cc}\left\{(x,y)\right|{(x-x_0)}^2+y^2<{\mathrm{<figure-callout\; id="0"\; label="R"\; filenames="HDA0000060526880000021.png,HDA0000060526880000032.png"\; state="\{\{state\}\}">R</figure-callout>}}_0^2\},& {\mathrm{\&lambda;}}_{\mathrm{th}}^{\&prime;\&prime;}<1,\\ \left\{(x,y)\right|x>d/2\},& {\mathrm{\&lambda;}}_{\mathrm{th}}^{\&prime;\&prime;}=1\\ \left\{(x,y)\right|{(x-x_0)}^2+y^2>{\mathrm{<figure-callout\; id="0"\; label="R"\; filenames="HDA0000060526880000021.png,HDA0000060526880000032.png"\; state="\{\{state\}\}">R</figure-callout>}}_0^2\},& {\mathrm{\&lambda;}}_{\mathrm{th}}^{\&prime;\&prime;}>1\end{array}\right.---\left(14\right)$

X wherein ₀=d/ (1-λ " _Th), As λ " _Th≠ 1 o'clock, this zone becomes one can find the solution border circular areas.Similarly, regional P above ₂,

It then is a sector region.So far, η _{I, j}Can be in the hope of being:

η _i，j＝P∩{(x，y)|x ²+y ²＜r _i ²}. (15)

This is the intersection of two circles, in like manner can get P ₂

To sum up, when target P eNB has only an adjacent MeNB or PeNB interference source, each independently interference region try to achieve.Can obtain total interference region by formula (4).Known desirable interference region area δ _iPrerequisite under, the width of annulus can be in the hope of being:

$\mathrm{\&Delta;}{r}_i=r_i-\sqrt{r_i^2-{\mathrm{\&delta;}}_i/\mathrm{\&pi;}}.---\left(16\right)$

Suppose that PeNB i reduces its covering radius to r _i-Δ r _i, guarantee the service quality of UE in the overlay area.This is equivalent to the access threshold that has improved the base station, has superposeed one in original base station pilot signals intensity and has born gain.The distinctive side-play amount of PeNB, β _{I, d}, can calculate accordingly:

${\mathrm{\&beta;}}_{i,d}=b_p\log (r_i-{\mathrm{\&Delta;r}}_i)-b_p\log r_i=b_p\log \frac{r_i-{\mathrm{\&Delta;r}}_i}{r_i}.---\left(17\right)$

Accompanying drawing 4 has provided the method flow schematic diagram of the embodiment of the invention, and Fig. 5 has provided sequential chart, and the method includes the steps of:

1. each eNB sets up the database of an adjacent eNB parameter;

2. when a PeNB opens or closes, adjacent eNB is given notice;

3. each eNB periodic with the adjacent eNB interactive information, this information comprises the configuration parameter of self, also comprises the configuration parameter of other eNB forwarding in the database in case of necessity;

4. each PeNB upgrades the self database parameter, and calculates the access control side-play amount;

5. each PeNB informs UE in the zone with side-play amount with the pilot tone form;

6. UE finishes the residential quarter selection according to receiving signal strength signal intensity and side-play amount.

Distribute embodiment to verify the superiority of the present invention in the residential quarter access control of focus overlay network according to a concrete resource below.

In embodiments of the present invention, use 3GPP scene 1 as assessment scene, cell site spacing 500m, system bandwidth 10MHz, user moving speed 3kmph; Adopt hexagon rule cell deployment, dispose 7 residential quarters altogether, 3 sectors/cells are used the Wraparound algorithm, every sector deployment 4 or 10 PeNB (N=4 or 10); Every sector 60 users, 4 UE of the even dispenser of every PeNB wherein, the even dispenser of all the other 60-4N is in whole sector zone; Minimum spacing 40m between the PeNB, minimum spacing 75m between PeNB and the MeNB, minimum spacing 10m between PeNB and the UE, minimum spacing 35m between MeNB and the UE; The total transmitted power 46dBm of MeNB, the total transmitted power 30dBm of PeNB; UE is to MeNB path loss L=128.1+37.6log10 (R), and UE is to PeNB path loss L=140.7+36.7log10 (R), and R is unit with km; MeNB is to UE shadow fading standard deviation 8dB, and PeNB is 10dB to UE; The decline of ITU-UMi small scale, the antenna strategy is the 2x2 Single User MIMO, no antenna polarization; Usage ratio equity dispatching device; Frequently select PMI/CQI, the 5ms feedback cycle, the 6ms feedback delay, ideal communication channel is estimated; HARQ adopts and appends merging, retransmits for 3 times at the most; The MMSE receiver; Penetration loss 20dB, MeNB/PeNB antenna gain 14/5dBi, UE antenna gain 0dBi.

The typical method of contrast comprises: RSRP, also namely select serving BS according to strong cohesiveness collection of letters road intensity; The constant offset amount, also namely all PeNB use identical side-play amount.

Fig. 6 has shown under the 4PeNB/ sector, the UE large scale distribution results of designed method and typical method.As seen from Figure 6, along with the increase of constant offset amount, more UE selects to insert PeNB, and this part UE has been subjected to the loss in the large scale decline.

Fig. 7 and Fig. 8 shown respectively 4 and 10PeNB/ sector situation under, UE inserts the ratio of PeNB.

Fig. 9 and Figure 10 have contrasted institute's extracting method and the performance of other typical method on residential quarter average frequency spectrum utilance and the cell edge availability of frequency spectrum respectively.By assessment data as seen, contrast RSRP method, the inventive method has significantly improved the cell edge availability of frequency spectrum under the prerequisite that residential quarter average frequency spectrum utilance is lost slightly; Average and the cell edge availability of frequency spectrum is improved in the residential quarter for the method for contrast constant offset amount, the inventive method." constant offset amount " in Fig. 7～10 in " RE " presentation graphs 6, " design flow " are " the design side-play amount " among Fig. 6.

It is to be noted, though the assessment of embodiment is at cover specific focus overlay network framework and a system parameters and since the present invention program have very strong generality (be in particular in: one side on base station deployment quantity and the mode without limits; On the other hand, to eNB in configuration such as power, antenna also without limits), therefore, when method of the present invention was applied to have in the focus overlay network of heterogeneous networks framework and the system parameters, the present invention program still can embody superiority.

As can be seen from the above embodiments, community access control method of the present invention by analyzing the disturbed condition that different PeNB are subjected to, for it designs different access control side-play amounts, has taken into full account the concrete environment of each PeNB in the residential quarter is selected.This method can effectively improve the data rate of edge customer under the prerequisite that keeps system's average frequency spectrum utilance, make offered load more balanced, and computational complexity is low, has stronger practicality

The above only is embodiments of the present invention; should be pointed out that for those skilled in the art, under the prerequisite that does not break away from the technology of the present invention principle; can also make some improvement and modification, these improve and modification also should be considered as protection scope of the present invention.

Claims (9)

1. a community access control method is characterized in that, may further comprise the steps:

S1, each the little base station PeNB that is arranged in the residential quarter obtains the parameter of adjacent base station periodically;

S2, each PeNB be according to the parameter of the adjacent base station that obtains, and according to this base station of described calculation of parameter in the side-play amount that inserts on the thresholding;

S3, each PeNB is broadcast to the user with the side-play amount of this base station with the form of pilot tone;

S4, the user is superimposed upon on the pilot power of PeNB by the side-play amount of each PeNB that will receive, thereby the received power of PeNB is revised, and finishes the residential quarter and selects;

The method of calculating side-play amount among the step S2 is subjected to adjacent base station by PeNB and disturbs stack level afterwards to determine, specifically calculates according to following steps:

1. define user's reception signal interference ratio SIR thresholding λ _Th, as weighing the separation whether user can accept base station normal service level;

2. to current PeNB, select an one adjacent base station, only under the influence of this adjacent base station, user SIR thresholding is less than λ in the current PeNB coverage in calculating _ThInterference region;

3. select other adjacent base station of described current PeNB successively, calculate the only described interference region under the influence of selected adjacent base station, each interference region is asked union according to the mode of set, as total interference region of current PeNB;

4. occupy the size of current PeNB area coverage according to total interference region, calculate current PeNB access control side-play amount;

5. with constant of gained side-play amount stack, as the result of calculation of side-play amount.

2. community access control method as claimed in claim 1 is characterized in that, described residential quarter is arranged in the focus overlay network, and each described residential quarter comprises a macro base station MeNB and some PeNB, and described adjacent base station is MeNB or PeNB.

3. community access control method as claimed in claim 2 is characterized in that, PeNB uses omnidirectional antenna, and macro base station MeNB uses fan antenna or omnidirectional antenna.

4. community access control method as claimed in claim 1 is characterized in that, the mode of PeNB acquisition parameter is among the step S1: adjacent base station directly transmits parameter by interface, and perhaps, other base station or upper level network element are by the interface retransmitting paramater.

5. community access control method as claimed in claim 1 is characterized in that, among the step S1, the parameter that each PeNB obtains comprises: the geographical position of base station, transmitted power; The base station is to the channel large scale fading factor of this PeNB.

6. community access control method as claimed in claim 5 is characterized in that, among the step S1, set in advance the cycle that each PeNB obtains the parameter of adjacent base station according to network environment, and for geographical position, the transmitted power of base station, it is mutual only to carry out primary information, or initiates mutual according to request; For the channel large scale fading factor of base station to this PeNB, the mutual cycle is more than or equal to hundred Milliseconds.

7. community access control method as claimed in claim 1 is characterized in that, calculates the interference region when and if only if exists an adjacent base station, is divided into two classes:

1. when adjacent base station is the macro base station MeNB of use fan antenna, use computer software to calculate;

2. when adjacent base station is omnidirectional antenna, calculate by closed solutions.

8. community access control method as claimed in claim 1 is characterized in that, the process that step is calculated the access control side-play amount by total interference region in 4. comprises the steps:

Suppose that ideally total interference region is an annular section of current PeNB coverage edge, according to the area of total interference region, try to achieve the width of this annular section; Only serving annular section with current PeNB then is target with interior user, dwindles the covering radius of current PeNB, and improves the threshold value of access power, obtains corresponding access control side-play amount thus.

9. as claim 1,7 ~ 8 each described community access control methods is characterized in that, step 5. in employed constant pre-defined by network terminal, and for all PeNB, this constant is consistent.

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