Summary of the invention
In view of this, the purpose of this invention is to provide a kind of resource allocation method of taking into account the Home eNodeB of this sub-district and adjacent area transmission performance and signal interference ratio simultaneously, this method is not only considered the interference of Home eNodeB to this sub-district, simultaneously by interference prediction, guarantee that shared PRB is no more than the setting thresholding to the interference of adjacent area, take all factors into consideration and take into account the communications performance of this sub-district and adjacent area again, finally realize the prioritization of PRB, be used to instruct newly-built Home eNodeB to carry out resource distribution.
In order to reach the foregoing invention purpose, the invention provides a kind of resource allocation method of Home eNodeB, it is characterized in that: Home eNodeB predicts that at first it takies the interference of each Physical Resource Block PRB (Physical Resource Block) back to this sub-district and adjacent area generation, the maximum interference threshold of taking all factors into consideration this sub-district and adjacent area again and being allowed, judge whether each PRB is available, and on available PRB basis, try to achieve its corresponding transmission power; Based on these available PRB transmitting powers, calculate its signal interference ratio in this sub-district then, according to the signal interference ratio numerical values recited it is carried out the resource distribution that descending is used to instruct newly-built Home eNodeB again.
Accompanying method comprises following operating procedure:
(1) carries out initialization operation: system parameters is set and obtains the required neighboring BS information of resource distribution;
(2) predict the interference of this sub-district,, calculate the transmitting power lower limit of each PRB according to the interference threshold value that system is provided with;
(3) predict the interference of each adjacent area,, calculate the upper limit of emission power of each PRB according to the interference threshold value of each adjacent area;
(4) each PRB of calculating of comprehensive above-mentioned two steps screen available PRB and definite its transmitting power at the transmitting power lower limit and the upper limit of emission power of this sub-district;
(5) based on the transmitting power of available PRB, calculate the signal interference ratio of this available PRB in this sub-district, again that these are available PRB is according to the big or small descending of its signal interference ratio numerical value, promptly to available PRB execution priority ordering;
(6) Home eNodeB is according to the needed PRB quantity in this sub-district, select the available PRB of respective numbers successively according to prioritization, generate the relevant information table of this sub-district: the PRB of local Home eNodeB takies the PRB transmitting power table of table, local Home eNodeB and the interference threshold table of local Home eNodeB, upgrades the interference threshold table of adjacent area simultaneously.
The innovation part of the inventive method is: the notion of introducing the adjacent area interference prediction: each Home eNodeB is set up the interference threshold table, and it comprises the maximum interference threshold value of being tolerated on the shared PRB of this Home eNodeB.When new Home eNodeB is set up, can obtain this interference threshold table information by information interaction with the adjacent area, simultaneously by behind the shared PRB of prediction, must be to the interference that the adjacent area produces less than the corresponding requirements of this thresholding table, thereby try to achieve the upper limit of emission power on the corresponding PRB, with the additional conditions of this restrictive condition, just realized taking into account simultaneously the PRB prioritization techniques scheme under this sub-district and the adjacent area communication performance again as the conventional P RB selection scheme of only considering this area interference.
Embodiment
For making the purpose, technical solutions and advantages of the present invention clearer, the present invention is described in further detail below in conjunction with drawings and Examples.
As everyone knows, in the LTE-A communication system, the allocation unit of frequency resource is Physical Resource Block PRB, and promptly each PRB takies time slot, i.e. a 0.5ms on time domain; And on frequency domain, take 12 subcarriers, amount to 180khz.
The present invention is a kind of resource allocation method of Home eNodeB: after newly-built Home eNodeB predicts that at first it takies each PRB, interference to this sub-district and adjacent area generation, the maximum interference threshold of taking all factors into consideration this sub-district and adjacent area again and being allowed, screening and judge whether each PRB is available and is tried to achieve its corresponding transmission power on available PRB basis; Then based on the transmitting power of these available PRB, calculate its signal interference ratio in this sub-district,, it is carried out descending descending again according to signal interference ratio numerical value, promptly, be used to instruct the resource distribution of newly-built Home eNodeB to available PRB execution priority ordering.
Referring to Fig. 1, introduce each concrete operations step of the inventive method:
Step 1, newly-built Home eNodeB is carried out initialization operation: system parameters is set and obtains the required neighboring BS information of resource distribution.This step 1 comprises following content of operation (referring to shown in Figure 2):
(11) Home eNodeB start at first works in terminal pattern, and by adjacent area around inserting, the PRB that obtains each adjacent area takies the PRB transmitting power table of table, each adjacent area and the interference threshold table of each adjacent area.Wherein, the PRB of each adjacent area takies the character in the table (referring to Fig. 8)
Each adjacent area that is used to write down sub-district, Home eNodeB place takies the situation that sequence number is the PRB of k, and its expression formula is:
In the formula, natural number subscript k and subscript j are respectively the adjacent area sequence number of PRB sequence number and sub-district, Home eNodeB place, the maximum of k, are that available PRB adds up to K, and j is certain the adjacent area sequence number among the adjacent area set N.
Character in the PRB transmitting power table (referring to Fig. 9) of adjacent area
The adjacent area that is used for LSN and is j is the transmitting power on the PRB of k in sequence number.
Interference threshold value in the interference threshold table (referring to Figure 10) of adjacent area
The adjacent area that is used for LSN and is j is the maximum interference threshold that can tolerate on the PRB of k in sequence number.
(12) Home eNodeB works in base station mode, and following system parameters is set: the signal interference ratio lower limit STR of available PRB sum K, each PRB
MinMaximum transmission power p with each PRB
Max
(13) Home eNodeB takies situation according to the PRB of each adjacent area in the step (11), preferentially selects remaining idle PRB, and with its maximum transmission power p
MaxThe terminal of temporary transient service current area.
(14) Home eNodeB is added up according to the measurement parameter of each terminal to report in the setting-up time, obtains the average channel gain g in this sub-district, and the average channel gain g between this sub-district and the adjacent area j
j
(15) Home eNodeB finishes initialization operation, prepares to utilize the information of step (11), (12) and (14), begins to carry out the prioritization scheme of PRB.
Step 2, Home eNodeB are predicted the interference of this sub-district, again according to the interference threshold value of system's setting, calculate the transmitting power lower limit of each PRB under the prediction of this area interference.This step 2 comprises following content of operation:
(21) Home eNodeB begins each PRB of poll in regular turn from k=1: after promptly taking each PRB by prediction, the interference that this sub-district is produced is in the hope of the transmitting power lower limit of corresponding PRB, be each PRB transmitting power minimum value.
(22) with the sequence number be the transmitting power p of the PRB of k
kBe independent variable, calculate the signal interference ratio SIR of each PRB in this sub-district according to the following equation
kValue:
In the formula, g is the average channel gain of this sub-district, g
jBe the average channel gain between adjacent area j and this sub-district,
For sequence number is the transmitting power of the PRB of k at adjacent area j, and N is the set or the sum of all adjacent areas of this sub-district.
(23) according to the signal interference ratio lower limit SIR of each PRB of initial setting up
Min, the signal interference ratio computing formula in the integrating step (22) obtains following inequality:
And then try to achieve the transmitting power lower limit of each PRB of this sub-district
Step 3, Home eNodeB are predicted the interference of each adjacent area, according to the interference threshold value of each adjacent area, calculate the upper limit of emission power of each PRB.This step 3 comprises following content of operation:
(31) Home eNodeB each adjacent area j of poll in regular turn, (j ∈ N) promptly carries out following step (32) and (33) to each adjacent area circulation, until traveling through all adjacent areas; So that after predicting that this sub-district takies the PRB that sequence number is k, to the interference that each adjacent area j produces, finally trying to achieve this sub-district is on the PRB of k in sequence number, satisfy all adjacent area interference threshold values upper limit of emission power, be the transmitting power maximum.
(32) with the sequence number be the transmitting power p of the PRB of k
kBe independent variable, calculate according to the following equation and take the interference that this PRB produces adjacent area j
(33) finding adjacent area j in the interference threshold table of each adjacent area from step (11) is the maximum interference threshold value that PRB tolerated of k in sequence number
Interference calculation formula in the integrating step (32) again
Obtain following inequality:
And then try to achieve maximum transmission power on the PRB that this sub-district that adjacent area j can tolerate is k in sequence number:
(34) calculate maximum transmission power on the PRB that this sub-district that can tolerate each adjacent area is k in sequence number after, choose wherein that this sub-district of conduct of numerical value minimum is the maximum transmission power that PRB allowed of k in sequence number, promptly obtain final upper limit of emission power: p
k Max=min{j → p
k Max, so that can satisfy the requirement of the interference threshold value of all adjacent areas.
Step 4, comprehensive above-mentioned two steps 2 and 3 each PRB that calculates are in the transmitting power lower limit and the upper limit of emission power of this sub-district, the transmitting power of screening available PRB and definite each available PRB.
This step 4 comprises following content of operation:
(41) judge that sequence number is the transmitting power lower limit p of PRB under the prediction of this area interference of k
k MinWith its maximum transmission power p under the interference prediction of adjacent area
k MaxAnd the maximum transmission power p of initial setting up in the step (12)
MaxNumerical values recited, if p
k MinSatisfy less than two upper limit: p simultaneously
k Min<p
k MaxAnd p
k Min<p
Max, promptly these three parameter values scopes have common factor and when not conflicting, and show that this sequence number is that the PRB of k is available PRB, then carries out subsequent step (42); Otherwise, show that this sequence number is that the PRB of k is unavailable, need return execution in step (2), the beginning poll next one (k+1) sequence number PRB;
(42) because of this sequence number is that the PRB of k is available PRB, trying to achieve this sequence number is the transmitting power p of the available PRB of k
k=min{p
k Max, p
Max.
Step 5 based on the transmitting power of available PRB, is calculated the signal interference ratio of this available PRB in this sub-district, and again that these are available PRB is according to the big or small descending of its signal interference ratio numerical value, promptly to available PRB execution priority ordering.This step 5 comprises following content of operation:
(51) sequence number that obtains based on above-mentioned steps is the transmitting power p of the available PRB of k
k, calculating this sequence number according to the following equation is the signal interference ratio of the available PRB of k for this sub-district
(52) all sequence numbers PRB that can use that judged whether poll promptly judge whether k=K, if then carry out subsequent step (53); Otherwise, return execution in step (2), beginning poll Next Sequence PRB.
(53) each is available PRB is according to its signal interference ratio SIR
kNumerical values recited carry out descending, promptly to each available PRB execution priority ordering.
Step 6, Home eNodeB be according to the needed PRB quantity in this sub-district, selects the available PRB of respective numbers successively according to prioritization, generates the relevant information table of this sub-district, upgrades the interference threshold table of adjacent area simultaneously.The relevant information table of this sub-district that this step generates comprises:
The PRB of local Home eNodeB takies table (referring to Fig. 3), and this form is the available PRB prioritization that calculates according to step 5, and the required PRB number in this sub-district obtains.
The PRB transmitting power table (referring to Fig. 4) of local Home eNodeB, this form is according to selected available PRB, the transmitting power of determining in the corresponding step 4 obtains.
The interference threshold table (referring to Fig. 5) of local Home eNodeB, interference threshold value I wherein
Max kRepresent that this sub-district is the interference maximum that can tolerate on the PRB of k in sequence number, this parameter-definition is:
If this sub-district does not take the PRB that this sequence number is k, then I
Max kBe infinity;
If this sub-district takies the PRB that sequence number is k, then I
Max kComputing formula be:
In the formula, SIR
kSystem parameters for initial setting in the step (12): the signal interference ratio lower limit of each PRB.
This step also will be upgraded the interference threshold table (referring to Figure 10) of adjacent area, threshold value wherein simultaneously
Represent the real-time interference maximum that each adjacent area can be tolerated on each PRB, the real-time update process of this parameter is: calculate the interference of each shared PRB of this sub-district to the adjacent area respectively earlier: finding this adjacent area j at adjacent area interference threshold table is the maximum interference threshold value that can tolerate on the PRB of k in sequence number
This sub-district of poll is the interference that produces on the PRB of k in sequence number to each adjacent area j respectively again
Find the solution then
Poor, be the real-time interference threshold value in adjacent area after the renewal.
The various resource data information tables among following brief description Fig. 3~Figure 10 and the situation of accompanying drawing:
PRB referring to local Home eNodeB shown in Figure 3 takies table, row in the form (PRB) represent each available PRB:PRB1, PRB2 ..., PRBK, row (C) is represented the sign ID of this sub-district, ρ in the middle of (row in the form among following Fig. 4 and Fig. 5 are identical therewith with the connotation of row, repeat no more)
kRepresent whether this sub-district takies the PRB of sequence number for row k, and parameter-definition is as follows:
Referring to the PRB transmitting power table of local Home eNodeB shown in Figure 4, middle p
kRepresent that this sub-district is the transmitting power on the available PRB of k in sequence number.
Referring to the interference threshold table of local Home eNodeB shown in Figure 5, middle I
Max kRepresent that this sub-district is the maximum interference that can tolerate on the PRB of k in sequence number.
Referring to Fig. 6, left figure (A) is a three-dimensional scenic of describing Home eNodeB embodiment, the situation that the Home eNodeB multilayer was disposed during it was more realistic; Right figure (B) has set forth under the multilayer deployment scenario, the notion of Home eNodeB adjacent area: suppose that newly-built Home eNodeB is that number in the figure is 7 sub-district, the sub-district of then corresponding label 1~6 is each adjacent area of sub-district 7, and 1-7 wherein is each sub-district ID.In actual scene, judge that the index of adjacent area can be the average channel gain of minizone, promptly set a threshold value, be higher than the adjacent area that is of this threshold value, otherwise be non-adjacent area, the physical significance of adjacent area and non-adjacent area is:
Non-adjacent area: take with the same interference that PRB produced in this sub-district and can ignore, promptly channel gain is lower than and sets thresholding and can think the right and wrong adjacent area.
The adjacent area: take with the same interference that PRB produced in this sub-district and can not ignore, but as long as disturb and setting below the thresholding, can shared this PRB.Be that channel gain is higher than and sets thresholding and just think the adjacent area.
Referring to newly-built Home eNodeB shown in Figure 7 and the average channel gain table of neighboring interval: C
jThe ID that represents corresponding adjacent area; g
jAverage channel gain between expression adjacent area j and this sub-district, because in the present embodiment, the adjacent area of sub-district 7 is 1~6, can get table shown in Figure 7 thus.
The PRB that obtains the adjacent area referring to newly-built Home eNodeB shown in Figure 8 takies table, and this table is the set that the PRB of all adjacent areas is taken table (being table shown in Figure 3).
Obtain the PRB transmitting power table of adjacent area referring to newly-built Home eNodeB shown in Figure 9: this table is the set of the PRB transmitting power table (being table shown in Figure 4) to all adjacent areas.
Referring to the interference threshold table of newly-built Home eNodeB acquisition adjacent area shown in Figure 10, this table is the set of the interference threshold table (being table shown in Figure 5) to all adjacent areas.
The above only is preferred embodiment of the present invention, and is in order to restriction the present invention, within the spirit and principles in the present invention not all, any modification of being made, is equal to replacement, improvement etc., all should be included within the scope of protection of the invention.