CN109391897A - Site selection method, device and storage medium towards the deployment of intensive small station - Google Patents
Site selection method, device and storage medium towards the deployment of intensive small station Download PDFInfo
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- CN109391897A CN109391897A CN201710651612.0A CN201710651612A CN109391897A CN 109391897 A CN109391897 A CN 109391897A CN 201710651612 A CN201710651612 A CN 201710651612A CN 109391897 A CN109391897 A CN 109391897A
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W4/00—Services specially adapted for wireless communication networks; Facilities therefor
- H04W4/02—Services making use of location information
- H04W4/025—Services making use of location information using location based information parameters
- H04W4/026—Services making use of location information using location based information parameters using orientation information, e.g. compass
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W36/00—Hand-off or reselection arrangements
- H04W36/0005—Control or signalling for completing the hand-off
- H04W36/0083—Determination of parameters used for hand-off, e.g. generation or modification of neighbour cell lists
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W36/00—Hand-off or reselection arrangements
- H04W36/08—Reselecting an access point
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W36/00—Hand-off or reselection arrangements
- H04W36/24—Reselection being triggered by specific parameters
- H04W36/30—Reselection being triggered by specific parameters by measured or perceived connection quality data
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W36/00—Hand-off or reselection arrangements
- H04W36/24—Reselection being triggered by specific parameters
- H04W36/32—Reselection being triggered by specific parameters by location or mobility data, e.g. speed data
Abstract
The invention discloses a kind of site selection method, device and storage mediums towards the deployment of intensive small station, to solve the problem of website handover failure and the excessively high handover overhead of the frequent bring of website in super-intensive network.The method includes: to estimate that user is in the first residence time of the overlay area of first object website for services sites；When first residence time is less than preset switching time thresholding, the first object website is rejected in website handoff procedure.The present invention, according to the residence time of estimation, carries out website selection, to reduce switching rate, and reduces the generation of unnecessary switching during website selects；To effectively solve the problems, such as the excessively high handover overhead of frequent switching bring in super-intensive network.
Description
Technical field
The present invention relates to field of mobile communication, more particularly to a kind of site selection method towards the deployment of intensive small station,
Device and storage medium.
Background technique
Future wireless network needs to meet the high data rate video traffic of explosive increase, and a large amount of different types are moved
The access demand of dynamic equipment.Super-intensive network (Ultra-Dense Networks, UDN) is to meet future 5G mobile data flow
The technical way of increased requirement, it realizes channeling by the density of increase base station deployment, especially low-power website
The tremendous increase of efficiency realizes the capacity boost of hundred times of orders of magnitude in local hot spot areas.On the one hand, Small cell (low function
The radio access node of rate) dense deployment can realize in hot spot region and shunt to the high speed of macro base station；On the other hand, big to having
The indoor scene of service distribution is measured, Small cell covering is more more efficient than macrocellular.Site deployment in super-intensive network can
To be planned by operator, can also be disposed according to actual needs by user.Therefore, the position of website is more in super-intensive network
Add randomization, the topological structure of network more dynamic.
Super-intensive network also brings a series of interference and mobility problem while significantly promoting network capacity.
Handover decision mechanism in existing LTE system is as follows, with the variation of channel condition and the movement of user, user from current
The received signal strength (RSRP) of services sites can change.When UE receive current service website (Source Site) order it
Afterwards, UE will in uplink periods send measurement report (MR) to current service website.If include in MR is any
The RSRP of website is more than switching lag difference (Offset) that Source Site is pre-set, and Source Site will send out the targeted sites
Switching is triggered after sending switching request, targeted sites to return to confirmation message.When purpose website RSRP than Source Site RSRP high
In Offset and when persistently meeting within the triggered time (TTT, Time-to-Trigger), user will be switched over.
In super-intensive network, since the coverage area in small station is smaller, the change frequency of user RSRP in moving process
It is higher, therefore user needs to carry out a large amount of measurement and reports work.Switching when meeting existing switch decision condition will occur,
Therefore the number for switching generation in super-intensive network greatly promotes.It needs to carry out a series of Signalling exchange in handoff procedure, because
This, frequent switching will bring excessively high handover overhead.
Summary of the invention
In view of the above drawbacks, discovery Producing reason is that existing website handover mechanism does not account for user's staying in website
Stay the time.
In view of above-mentioned discovery and in order to overcome drawbacks described above, the technical problem to be solved in the present invention is to provide one kind towards close
Site selection method, device and the storage medium for collecting small station deployment, to solve asking for website handover failure in super-intensive network
The problem of topic and the frequent bring of website excessively high handover overhead.
In order to solve the above technical problems, the site selection method that one of present invention is disposed towards intensive small station, described
Method is used for services sites, comprising:
Estimation user is in the first residence time of the overlay area of first object website；
When first residence time is less than preset switching time thresholding, described the is rejected in website handoff procedure
One targeted sites.
In order to solve the above technical problems, the website selection device that one of present invention is disposed towards intensive small station, including
Memory and processor, the memory are stored with the website towards the deployment of intensive small station and select computer program；The processing
When device executes the computer program, the step of to realize any one the method as above.
In order to solve the above technical problems, one of present invention computer readable storage medium, is stored with towards intensive small
The website disposed of standing selects computer program；When the computer program is executed by least one processor, such as taken up an official post with realizing
The step of the method for anticipating.
The present invention has the beneficial effect that:
Method, apparatus and storage medium in the present invention, by estimating that user's subsequent time is stayed in potential targeted sites
The time is stayed, during website selection, according to the residence time of estimation, website selection is carried out, to reduce switching rate, and subtracts
The generation of unnecessary switching is lacked；To effectively solve the problems, such as the excessively high handover overhead of frequent switching bring in super-intensive network.
Detailed description of the invention
Fig. 1 is a kind of flow chart of the site selection method towards the deployment of intensive small station in the embodiment of the present invention；
Fig. 2 is method application scenarios schematic diagram in the embodiment of the present invention；
Fig. 3 is a user movement model schematic simplified in the embodiment of the present invention；
Fig. 4 is the probability density function of residence time and cumulative distribution function figure in the embodiment of the present invention；
Fig. 5 is the simplification figure of Fig. 3；
Fig. 6 is influence schematic diagram of the residence time thresholding to handover failure number in fixed-direction of the embodiment of the present invention；
Fig. 7 and Fig. 8 is influence signal of the website selection mechanism to UHO rate and PP rate in fixed-direction of the embodiment of the present invention
Figure；
Fig. 9 and Figure 10 be in fixed-direction of the embodiment of the present invention website selection mechanism to switching times and handover failure number
Influence schematic diagram；
Figure 11 is that moving direction changes schematic diagram in the embodiment of the present invention；
Figure 12 is lagrangian polynomial fit schematic diagram in the embodiment of the present invention；
Figure 13 is influence schematic diagram of the residence time thresholding to handover failure number in on-fixed of embodiment of the present invention direction；
Figure 14 and Figure 15 is that influence of the website selection mechanism to UHO rate and PP rate is shown in on-fixed of embodiment of the present invention direction
It is intended to；
Figure 16 and Figure 17 be in on-fixed of the embodiment of the present invention direction website selection mechanism to switching times and handover failure
The influence schematic diagram of number；
Figure 18 is a kind of structural schematic diagram of the website selection device towards the deployment of intensive small station in the embodiment of the present invention.
Specific embodiment
Since the coverage area of website in super-intensive network is much smaller than traditional macrocellular, user switches in moving process
The frequency of generation will greatly improve.The selection gist of targeted sites is mainly website load and signal strength in the prior art.
For example, the website selection mechanism based on access probability factor, meanwhile, sentence once the received signal strength of targeted sites meets switching
Certainly criterion, then switching will execute.
Website distribution randomness is larger in super-intensive network, and coverage area is small and irregular, and user is in the state of movement
When, if will be frequent switching according to the website selection mechanism in existing LTE system, frequent switching be will lead to not
Necessary resource consumption, while handover delay also will affect the experience of user.
Based on of the invention the study found that the reason of generating above-mentioned frequent switching phenomenon is, existing handover mechanism does not have
Consider the residence time of website.Specifically, for the user of high-speed mobile, if still using the handover decision mechanism under LTE,
Due to the presence of Offset and TTT, so that it is in the central area of cell that the moment, which occurs, for switching, user loses synchronous with Source Site
Probability will greatly improve, so as to cause the generation of handover failure.In addition, the coverage area of website is not advised in super-intensive network
Then, if according to existing LTE switch decision criterion, user may certain site residence time it is shorter, it is not necessary to switch
The frequency of generation will greatly improve.In view of above-mentioned discovery, the website selection mechanism based on residence time under super-intensive network is designed
There is essential meaning to reduce unnecessary switching.
Therefore, in view of above-mentioned discovery, and in order to solve the excessively high handover overhead of frequent switching bring in super-intensive network
Problem, the present invention provides a kind of site selection method, device and storage mediums towards the deployment of intensive small station, below in conjunction with attached
Figure and embodiment, the present invention will be described in further detail.It should be appreciated that specific embodiment described herein only to
It explains the present invention, does not limit the present invention.
Embodiment one
As shown in Figure 1, the embodiment of the present invention provides a kind of site selection method towards the deployment of intensive small station, the method
For services sites, comprising:
S101, estimation user are in the first residence time of the overlay area of first object website；
S102 is rejected in website handoff procedure when first residence time is less than preset switching time thresholding
The first object website；That is, user is not switched in first object website.
The embodiment of the present invention is by estimating that user is in the first residence time of the overlay area of first object website；Work as institute
When stating the first residence time less than preset switching time thresholding, the first object website is rejected in website handoff procedure,
To realize by estimation user's subsequent time residence time in potential targeted sites, if user is in the targeted sites
When residence time is less than switching time thresholding, then during website selection the targeted sites can be skipped, to reduce
Switching rate, and reduce the generation of unnecessary switching；It is cut so that effectively frequent switching bring is excessively high in solution super-intensive network
Change overhead issues.
Targeted sites are potential website in the embodiment of the present invention, show that user may during website selects
The website being switched to from services sites.
On the basis of the above embodiments, it is further proposed that the variant embodiment of above-described embodiment, needs to illustrate herein
It is, in order to make description briefly, the difference with above-described embodiment only to be described in each variant embodiment.
The prefixes such as " first ", " second " for distinguishing element, parameter are used in the embodiment of the present invention only for having
Conducive to explanation of the invention, itself there is no specific meaning.
Optionally, described when first residence time is less than preset switching time thresholding, in website handoff procedure
After the middle rejecting first object website, comprising:
The user is switched to the second targeted sites from the services sites.
Optionally, before the first residence time of the overlay area that the estimation user is in first object website, comprising:
In the moving process of the user, the moving direction of the user is determined；
According to the moving direction, the first object website and second targeted sites are determined.
Before first residence time of the overlay area that the estimation user is in first object website, comprising:
In the moving process of the user, the moving direction of the user is determined；
According to the moving direction, the first object website and second targeted sites are determined.
It is optionally, described that the user is switched to the second targeted sites from the services sites, comprising:
Estimate that the user is in the second residence time of the overlay area of second targeted sites；
When second residence time is greater than or equal to the switching time thresholding, by the user from the service station
Point is switched to second targeted sites.
Optionally, described when first residence time is less than preset switching time thresholding, in website handoff procedure
It is middle to reject the first object website, comprising:
When first residence time is less than the switching time thresholding, determine that user described in middle position can receive
To the received signal strength of second targeted sites；
If the received signal strength is not less than receiving signal sensitivity, first mesh is rejected in website handoff procedure
Labeling station point；Wherein, the position among the services sites and second targeted sites is the middle position.
Optionally, the estimation user is in the first residence time of the overlay area of first object website, comprising:
Determine the overlay area of the first object website；
The user is calculated in the movement routine of the overlay area of the first object website；
Determine the length of the movement routine and the movement speed of the user；
According to the length and the movement speed, the residence time is determined.
Further, the overlay area of the determination first object website, comprising:
Divided according to Poisson Thiessen polygon, divides the overlay area of each website；Each website constitutes Poisson's point；
In the overlay area of division, the overlay area of the first object website is determined.
Wherein, each website is the radio access node for the low-power disposed towards intensive small station；Each website is at least
Including services sites, first object website and the second targeted sites.
Further, the movement routine of overlay area of the measuring and calculating user in the first object website, comprising:
Determine the moving direction of the user；
According to the moving direction, the motion track of the user is calculated；
Determine two intersection points of the motion track of measuring and calculating and the overlay area of the first object website, described two intersection points
Between motion track constitute the movement routine.
Wherein, the moving direction includes fixed-direction and on-fixed direction；
When the moving direction is on-fixed direction, the moving direction of the determination user, comprising:
By interpolation method, interpolation is carried out to the user location that at least two be obtained ahead of time are sequentially arranged, is obtained
Multinomial；
According to the polynomial tangent slope, the moving direction is determined.
Specifically, the interpolation method is Lagrange's interpolation；The multinomial is Lagrange interpolation polynomial.
Optionally, the method also includes:
Power control is carried out to the first object website, or
Shut down the first object website.
Detailed description of the present invention realization principle.
Sketch term and abbreviation involved in the embodiment of the present invention:
LTE Long Term Evolution long term evolution；
UE User Equipment user equipment；
UDN Ultra Dense Network super-intensive network；
RSRP Reference Signal Received Power Reference Signal Received Power；
PPP Poisson Point Process poisson process；
PVT Poisson-Voronoi Tessellations Poisson-Tyson segmentation；
SINR Signal to Interference and Noise Ratio Signal to Interference plus Noise Ratio；
PDF Probability Density Function probability density function；
CDF Cumulative Distribution Function cumulative distribution function；
RLF Radio Link Failure link failure；
HOF Handover Failure handover failure.
Primary concern is that the Small cells website of single layer in the embodiment of the present invention.Straight line with the arrow indicates in Fig. 2
It is the motion track of user.Poisson's point distribution, the coverage area of the Polygons Representation website where website are obeyed in the distribution of website
(i.e. overlay area).With the movement of user, user will be linked into different websites, and what L was indicated is user's motion track and clothes
The chord length (i.e. the length of movement routine) of business website coverage area polygon intersection.
Currently, there are mainly two types of the definition of super-intensive network: site density is greater than user density or site density is not low
In 1000 every sq-kms.Scene in this programme meets site density in super-intensive net definitions and often puts down not less than 1000
Square km.The position in small station has randomness.In view of actual application, the scene of small station dense distribution appears in the stream of people mostly
Measure larger, the more place of business demand, such as intensive block.
Small cell is the radio access node of low-power, can cover 10 meters to 200 meters of range, in contrast,
The coverage area of macrocellular can achieve several kilometers.
The key of method is to obtain user in the residence time of targeted sites, the embodiment of the present invention in the embodiment of the present invention
Convert the computational problem of residence time to the intersection problems of two-dimensional surface interior lines and polygon in geometry, what line indicated is to use
The motion track at family, Polygons Representation be website coverage area polygon.Therefore, the key solved the problems, such as is how to obtain
The motion track and website coverage area polygon of user.
The motion track of user can be fitted to obtain with passage path.Due to website in super-intensive network distribution randomness compared with
Greatly, therefore using poisson process to website distribution it models.Under the premise of website transmission power is equal, the covering of website
Area can be divided to obtain by Poisson-Thiessen polygon.Poisson-Thiessen polygon segmentation principle is based on two sampling points
Line makees perpendicular bisector, to ensure that the distance for arbitrarily putting sampling point in current polygon in polygon is nearest.Therefore,
The chord length (length of movement routine) that user's movement routine intersects with Thiessen polygon can be calculated on this basis, in conjunction with user
Current movement speed can be obtained by user in the residence time of the website.
User has determined potential targeted sites set by moving direction in handoff procedure, can in the embodiment of the present invention
With the residence time using estimation user in targeted sites.If residence time of the user in targeted sites is less than preset
Switching time thresholding, so that it may the targeted sites be rejected, i.e., do not consider the website, during switching so as to avoid not
The generation of necessity switching, reduces switching times.
The principle of fixed-direction:
In super-intensive network, if user is linked into always apart from nearest website, user will appear in moving process
The frequent replacement of services sites, so as to cause unnecessary expense.According to the motion track of user, if user is in mobile mistake
Nearest website is not accessed in journey always, but the shorter website of residence time is skipped by residence time estimation, then can
To efficiently reduce the number of switching.
During the present invention is implemented, the desired value of residence time is theoretically analyzed first.In two-dimensional surface, random sites model
A unlimited point sequence { O can be used0,O1,O2,...,Oi... } and it is described, wherein OiIndicate i-th of site (website)
Position, O0Indicate start position.For given site Oi, next site Oi+1With appointing in current site and two-dimensional surface
Meaning point is mutually indepedent.The movement routine of user can be write as set φ={ χ1,χ2,…,χi..., wherein χiExpression two continuous
Site Oi-1, OiBetween line segment.viMovement speed indicating user from (i-1)-th to i-th point.
Switching betides the overlay area that user is moved to another website from the overlay area of services sites.Assuming that website
Density namely the intensity of poisson process be λ, according to the mathematical property of Poisson-Tyson segmentation, for given straight line l, l with
Thiessen polygon intersects the average value countedThat is, when user is in tiTime in the length that moves be |
χi| when, if user always accesses nearest website, the mathematic expectaion for the switching times that user occurs in this course
Are as follows:
So, the switching rate of user whithin a period of time are as follows:
When user at the uniform velocity moves, the switching rate of user are as follows:
The average residence time of user is equal to the inverse of user's switching rate, therefore:
As shown in figure 3, a kind of user movement model of simplification, i.e. user are linear uniform motion.Justify on straight line in figure
Point indicates user site, other dots indicate that website, straight line indicate the motion track of user.User's the first two site is in website
In the coverage area of A, i.e. website A is current service website.With the movement of user, the motion track and website of user covers model
There are intersection points for the polygon enclosed, namely are switched.It can be seen from the figure that user's motion track and website C coverage area
Polygon intersection chord length it is shorter, when user at the uniform velocity moves, residence time of the user in website C is shorter.
The residence time of website depends on the movement speed of user and user's motion track intersects with website coverage area
Chord length.In fact, chord length is a random variable after Poisson-Thiessen polygon segmentation, specific point is obeyed
Cloth can obtain user in the mathematic expectaion and cumulative distribution of the residence time of website by theory deduction.
User passes through the probability density function for the chord length that arbitrary Poisson Thiessen polygon is crossed over are as follows:
Wherein, And
It can be obtained according to the mathematical relationship between cumulative distribution function and probability density function:
When user at the uniform velocity moves, according toThe cumulative distribution function of available residence time T are as follows:
Therefore, the probability density function of residence time are as follows:
As shown in figure 4, from the probability density function (PDF) of residence time as can be seen that site density it is higher, PDF curve
It is narrow and high；Site density is lower, and PDF curve is wide and short.When site density is fixed, the speed of user is faster, residence time
Cumulative distribution function (CDF) tends to 1 fastlyer.
There is purpose therefore to obtain the moving direction of user by moving projection for the movement of user, can instruct to switch
Website selection in the process.Fig. 5 is simplified scene figure, and arrow line indicates the user's moving direction obtained by prediction in figure,
What dot indicated is website, and that square indicates is user.
The transmission power of website is equal in the implementation case, while Offset=0dB and TTT=in handoff procedure
0ms.According to Poisson-Thiessen polygon segmentation principle, when user movement to current service website and potential website A connecting line
Perpendicular bisector l2When, since user works as user to the distance of current service website and being equidistant to potential website A at this time
The overlay area of website A will be entered when continuing movement, switching will occur at this time.Meanwhile when potential website (i.e. Target Station
Point) topology such as Fig. 5 when, the perpendicular bisector l of potential website A and B connecting line1Above region is by covering for potential website B
Cover area.Therefore, the straight line on user's moving direction and perpendicular bisector l1And l2The line segment of intersection is user's motion track and dives
In the chord length of website A overlay area polygon intersection.If the current movement speed of user is it is known that so chord length L and mobile speed
The ratio of degree v is exactly the time that user is resident in website:
When user is when the residence time of website A is lower than preset thresholding, must also guarantee to use in the embodiment of the present invention
RSRP when family is moved to Q point (user's being equidistant to website S and B at this time) is greater than receiving signal sensitivity RSRPRS, that is, use
Family, which has access to website B, could consider to skip website A.Wherein, receiving signal sensitivity and working frequency and bandwidth have relationship.
In the present invention, it is not necessary to switch (Unnecessary Handover, UHO) and be defined as after switching in Target Station
The residence time of point is lower than pre-set thresholding, it is not necessary to which switching rate is defined as the number that unnecessary switching occurs and total switching
The ratio of number:
Table tennis (Ping Pong, PP) rate is defined as the number of pingpang handoff and the ratio of total switching times:
Realize that embodiment method has the following effects that in the present invention based on fixed-direction principle.
Wherein, table 1 is simulation parameter
Table 1
| Parameter | Unit | Value |
| Site density | /km2 | 2000 |
| User velocity | m/s | 1,5 |
| Website transmission power | mW | 20 |
| TTT | ms | 0,80,160,320 |
| A3Offset | dB | 0,1,3 |
| Qin | dB | -6 |
| Qout | dB | -8 |
| Emulate area | m2 | 500*500 |
1) influence of the residence time thresholding to handover failure number:
Fig. 6 describes influence of the residence time thresholding to handover failure number, and user is the linear motion of 1m/s.It is based on
Offset=0dB, TTT=0ms in the website selection of RSRP.As can be drawn from Figure 6: a) with the increase of residence time thresholding,
Handover failure number tended to be steady before this, then was gradually increasing.The reason of causing this phenomenon is if certain potential website is resident
Time is longer, skips the potential website during website selection and is then easy to cause the generation of link failure, to cause to cut
It changes unsuccessfully.B) work as TthresholdIt will lead to the rising of handover failure number when > 7.
2) influence of the website selection mechanism to UHO rate and PP rate:
Fig. 7 is user velocity when being 1m/s, website selection mechanism based on residence time and different Offset and TTT configuration
Under the website selection mechanism based on RSRP PP rate and UHO rate compare.At this point, when the website that UHO is defined as after switching is resident
Between be lower than 5 seconds.
As can be drawn from Figure 7: a) UHO rate is mainly influenced by Offset value.B) work as Offset=0dB, TTT=0ms
When, the website selection scheme (Offset=0dB, TTT=0ms, similarly hereinafter) based on residence time can reduce 68% PP rate with
And 74% UHO rate.Work as Offset=0dB, the unnecessary switching of when TTT=0ms and PP switching are easy to occur, however, in mesh
Labeling station point select during by estimation user in latent residence time in the station, when camped between estimated value lower than preparatory
The potential website will be skipped when the thresholding of setting, therefore can be effectively reduced unnecessary switching and PP switching.C) work as Offset
When=3dB, TTT=320ms, the website selection scheme based on residence time can reduce 54% PP rate and 62% UHO
Rate.
Fig. 8 is user velocity when being 5m/s, website selection mechanism based on residence time and different Offset and TTT configuration
Under the website selection mechanism based on RSRP PP rate and UHO rate compare.At this time, it is not necessary to which switching is defined as the website after switching
Residence time is lower than 1 second.As can be drawn from Figure 8: a) work as Offset=0dB, when TTT=0ms, the website choosing based on residence time
The scheme of selecting can reduce 70% PP rate and 78% UHO rate.B) work as Offset=3dB, when TTT=320ms, based on resident
The website selection scheme of time can reduce 49% PP rate and 63% UHO rate.
3) influence of the website selection mechanism to switching times and handover failure number:
As shown in figure 9, it is 1m/s that (a), which is user velocity, TTT is fixed in the website selection based on RSRP and Offset changes
When with based on residence time website selection switching times compared with.As shown in figure 9, (b) be user velocity be 1m/s, be based on
RSRP website selection in Offset fix and TTT change when with based on residence time website selection handover failure number ratio
Compared with.
Therefrom in Fig. 9 (a) it can be seen that a) when TTT is fixed, the switching times of the website selection based on RSRP with
The increase of Offset and reduce.This is because switching is more difficult to occur, therefore switching times are declined when Offset increases.
B) when Offset value is respectively 0dB, 1dB, 3dB, the website selection based on residence time can reduce 29%, 18%, 9%
Switching times.Main cause is that the website selection based on residence time further reduces the hair of unnecessary switching and PP switching
It is raw.
In Fig. 9 (b) it can be seen that a) when Offset is fixed, the handover failure number of the website selection based on RSRP
Increase with the increase of TTT.This is because TTT is longer, it is easier to switch unsuccessfully during waiting TTT duration.
B) when TTT value is respectively 80ms, when 160ms, 320ms, the website selection based on residence time can reduce 19%, 25%,
28% handover failure number.Main cause is in the website selection based on residence time if the estimated value of residence time is greater than
Preset thresholding then user can be directly accessed the website and without waiting for TTT duration, therefore can reduce handover failure
Number.
As shown in Figure 10, it is 5m/s that (a), which is user velocity, and TTT is fixed in the website selection based on RSRP and Offset becomes
When change compared with the switching times of the website selection based on residence time.As shown in Figure 10, (b) be user velocity be 5m/s, base
In RSRP website selection in Offset fix and TTT change when with based on residence time website selection handover failure number
Compare.
From Figure 10 (a) it can be seen that a) when TTT is fixed, Offset value is respectively 0dB, when 1dB, 3dB, be based on
The website selection of residence time can reduce 27%, 17%, 7% switching times.B) compared with Fig. 9 (a), due to mentioning for speed
Rise the promotion for resulting in switching times.
From Figure 10 (b) it can be seen that a) when Offset is fixed, TTT value is respectively 80ms, when 160ms, 320ms,
Website selection based on residence time can reduce 17%, 21%, 24% handover failure number.B) compared with Fig. 9 (b), speed
Degree promotes the promotion that will also result in handover failure number.
Based on the above principles, the embodiment of the present invention improves the website selection in existing LTE handoff procedure, different
Website selection mechanism in existing LTE handover decision mechanism, website of the embodiment of the present invention in handoff procedure are examined when selecting
User has been considered in latent residence time in the station.Firstly, being modeled using poisson process to website distribution, based on pool
Pine-Thiessen polygon principle divides the coverage area of website, passes through analysis user's motion track and website coverage area
The chord length of polygon intersection obtains residence time of the user in the website.If user estimates in latent residence time in the station
Evaluation is lower than preset thresholding, and the potential website will be selectively skipped in handoff procedure, to lose not increasing switching
The generation of unnecessary switching and pingpang handoff is reduced under the premise of losing number.
The principle in on-fixed direction:
The moving direction of user is not fixed in practical application scene.In existing literature, user's mobility model can be with
5 classes are greatly classified into, are purely random model respectively, Time Dependent model, space relies on model, geography relies on model and mixed
Molding type.For purely random model also without dependence, modeling process is unrestricted.Mainly include random walk model, with
Seat in the plane point model and random direction model.Random sites model has the characteristics that easy to accomplish and extensive practicability,
Benchmark as user's mobility model.Therefore, in the present invention program embodiment, we consider simplified random sites models
(Random Waypoint Model) estimates user in latent residence time in the station in conjunction with the direction prediction of user.
In the random sites model of standard, the angle of user's moving direction is obeyed in [0,2 π] to be uniformly distributed.However, with
Family has certain directionality and purpose, the less change that wide-angle occurs of the moving direction of user during actual motion
Change.In order to make mobility model be more in line with the actual situation of movement of user, random sites model of the embodiment of the present invention to standard
It improves, modified RWP model is known as Simplified RWP (SRWP) in embodiments of the present invention.The present invention is implemented
The moving direction of user is roughly divided into 4 directions in example, on this 4 directions, the variation range of user's moving direction is reduced
It is as shown in figure 11 for [0, π]:
Due to the moving direction of user be it is unknown, we consider first obtain user moving direction.User exists
The track formed in moving process has certain rule, we can use function indicate in certain between tracing point
Connection.We can be observed user location in practice, obtain corresponding observation in place several different, draw
Ge Lang interpolation method can find a multinomial, get the value observed in the point of each observation just, such multinomial
Formula is known as Lagrange interpolation polynomial.For from mathematical meaning, Lagrange's interpolation can provide one and pass through just
The polynomial function of several known points on two-dimensional surface, as shown in figure 12.
In two-dimensional coordinate system, it is known that it is n's that n+1 coordinate points can generate highest power by Lagrange's interpolation
Polynomial fitting:
It is available after simplification:
F (x)=K0+K1x+K2x2+……+Knxn (13)
The user path multinomial being fitted by Lagrange interpolation polynomial current location tangent slope just
It is the current moving direction of user:
After obtaining the moving direction of user, calculate user's motion track and website cover chord length that polygon intersects and
Residence time estimation is similar with fixed-direction principle, therefore repeats no more.
Realize that embodiment method has the following effects that in the present invention based on on-fixed orientation principle.
1) influence of the residence time thresholding to handover failure number:
Figure 13 describes influence of the residence time thresholding to handover failure number, and user is the SRWP model of 1m/s.Base
Offset=0dB, TTT=0ms in the website selection of RSRP.As can be drawn from Figure 13: a) with the increasing of residence time thresholding
Add, the variation tendency of handover failure number is similar with Fig. 6: handover failure number tended to be steady before this, was then gradually increasing.B) this
When, when Tthreshold > 5, will increase handover failure number.
2) influence of the website selection mechanism to UHO rate and PP rate:
Figure 14 is that user velocity is 1m/s, and the website selection mechanism based on residence time is configured from different Offset and TTT
Under the website selection mechanism based on RSRP PP rate and UHO rate compare.At this time, it is not necessary to which switching is defined as the website after switching
Residence time is lower than 5 seconds.As can be seen from Figure 14: a) work as Offset=0dB, when TTT=0ms, the website based on residence time
Selection scheme can reduce 45% PP rate and 38% UHO rate.B) work as Offset=3dB, when TTT=320ms, based on staying
Stay the website selection scheme of time that can reduce 16% PP rate and 19% UHO rate.C) compared with Fig. 7, when speed is identical,
Since the moving direction of user is not fixed, it is not necessary to which switching rate and PP rate are promoted.
Figure 15 is that user velocity is 5m/s, and the website selection mechanism based on residence time is configured from different Offset and TTT
Under the website selection mechanism based on RSRP PP rate and UHO rate compare.At this time, it is not necessary to which switching is defined as the website after switching
Residence time is lower than 1 second.As can be seen from Figure 15: a) work as Offset=0dB, when TTT=0ms, the website based on residence time
Selection scheme can reduce 52% PP rate and 36% UHO rate.B) work as Offset=3dB, when TTT=320ms, based on staying
Stay the website selection scheme of time that can reduce 17% PP rate and 14% UHO rate.C) Fig. 8 is compared, due to the shifting of user
Dynamic direction is not fixed, it is not necessary to which switching rate and Ping Pong rate are promoted.
3) influence of the website selection mechanism to switching times and handover failure number:
As shown in figure 16, it is 1m/s that (a), which is user velocity, and TTT is fixed in the website selection based on RSRP and Offset becomes
When change compared with the switching times of the website selection based on residence time.As shown in figure 16, (b) be user velocity be 1m/s, base
In RSRP website selection in Offset fix and TTT change when with based on residence time website selection handover failure number
Compare.
(a) is it can be seen that when TTT is fixed, when Offset value is respectively 0dB, 1dB, 3dB, based on resident from Figure 16
The website selection of time can reduce 42%, 26%, 16% switching times.
(b) when TTT value is respectively 80ms, 160ms, 320ms, is based on it can be seen that when Offset is fixed from Figure 16
The website selection of residence time can reduce 21%, 24%, 27% handover failure number.
As shown in figure 17, it is 5m/s that (a), which is user velocity, and TTT is fixed in the website selection based on RSRP and Offset becomes
When change compared with the switching times of the website selection based on residence time.
As shown in figure 17, (b) be user velocity be 5m/s when, based on RSRP website selection in Offset fix and TTT
When variation compared with the handover failure number of the website selection based on residence time.
(a) is it can be seen that when TTT is fixed, when Offset value is respectively 0dB, 1dB, 3dB, based on resident from Figure 17
The website selection of time can reduce 35%, 22%, 14% switching times.
(b) when TTT value is respectively 80ms, 160ms, 320ms, is based on it can be seen that when Offset is fixed from Figure 17
The website selection of residence time can reduce 15%, 19%, 21% handover failure number.
Method in the embodiment of the present invention realized by on-fixed orientation principle passes through estimation user being resident in the station
Time instructs the selection of targeted sites in handoff procedure, it is necessary first to lagrangian polynomial fit user movement routine is utilized,
By obtaining the moving direction of user to path polynomial derivation, and then analysis user's motion track and website coverage area are polygon
The chord length of shape intersection obtains user in the residence time of the website.If website residence time is lower than set thresholding, switching
The website will be selectively skipped in journey, to reduce the generation of unnecessary switching, reduces switching times.
Website selection scheme based on residence time estimation in the embodiment of the present invention is in handoff procedure first according to user
Moving direction determine potential Website Hosting, the choosing of targeted sites is instructed in latent residence time in the station by estimation user
It selects, avoids the generation of unnecessary switching.By simulating, verifying, the website selection scheme based on residence time estimation can be not
Switching times can be effectively reduced under the premise of increasing handover failure number, while reducing unnecessary switching and PP switching
Occur.
Embodiment two
As shown in figure 18, the embodiment of the present invention provides a kind of website selection device towards the deployment of intensive small station, the dress
It sets including memory 10 and processor 12, the memory 10 is stored with the website towards the deployment of intensive small station and selects computer journey
Sequence；When the processor 12 executes the computer program, to realize such as the step of any one of embodiment one the method.
Embodiment three
The embodiment of the present invention provides a kind of computer readable storage medium, and the storage medium is stored with towards intensive small station
The website of deployment selects computer program；When the computer program is executed by least one processor, to realize such as embodiment
The step of any one of one the method.
Computer readable storage medium can be RAM memory, flash memory, ROM memory, EPROM in the embodiment of the present invention
Memory, eeprom memory, register, hard disk, mobile hard disk, CD-ROM or any other form known in the art
Storage medium.A kind of storage medium lotus root can be connected to processor, thus enable a processor to from the read information,
And information can be written to the storage medium；Or the storage medium can be the component part of processor.Processor and storage are situated between
Matter can be located in specific integrated circuit.
It should be noted that embodiment two and embodiment three are in specific implementation, can also have refering to embodiment one
There is the technical effect of embodiment instrument, this will not be repeated here.
Above-described specific embodiment has carried out further the purpose of the present invention, technical scheme and beneficial effects
It is described in detail, it should be understood that being not intended to limit the present invention the foregoing is merely a specific embodiment of the invention
Protection scope, all within the spirits and principles of the present invention, any modification, equivalent substitution, improvement and etc. done should all include
Within protection scope of the present invention.
Claims (14)
1. a kind of site selection method towards the deployment of intensive small station, which is characterized in that the method is used for services sites, packet
It includes:
Estimation user is in the first residence time of the overlay area of first object website；
When first residence time is less than preset switching time thresholding, first mesh is rejected in website handoff procedure
Labeling station point.
2. the method as described in claim 1, which is characterized in that described when first residence time is less than preset switching
Between thresholding when, after rejecting the first object website in website handoff procedure, comprising:
The user is switched to the second targeted sites from the services sites.
3. method according to claim 2, which is characterized in that the estimation user is in the overlay area of first object website
The first residence time before, comprising:
In the moving process of the user, the moving direction of the user is determined；
According to the moving direction, the first object website and second targeted sites are determined.
4. method according to claim 2, which is characterized in that described that the user is switched to second from the services sites
Targeted sites, comprising:
Estimate that the user is in the second residence time of the overlay area of second targeted sites；
When second residence time is greater than or equal to the switching time thresholding, the user is cut from the services sites
Change to second targeted sites.
5. method according to claim 2, which is characterized in that described when first residence time is less than preset switching
Between thresholding when, the first object website is rejected in website handoff procedure, comprising:
When first residence time is less than the switching time thresholding, determine that user described in middle position can receive institute
State the received signal strength of the second targeted sites；
If the received signal strength is not less than receiving signal sensitivity, the first object station is rejected in website handoff procedure
Point；Wherein, the position among the services sites and second targeted sites is the middle position.
6. method according to claim 2, which is characterized in that the estimation user is in the overlay area of first object website
The first residence time, comprising:
Determine the overlay area of the first object website；
The user is calculated in the movement routine of the overlay area of the first object website；
Determine the length of the movement routine and the movement speed of the user；
According to the length and the movement speed, the residence time is determined.
7. method as claimed in claim 6, which is characterized in that the overlay area of the determination first object website, packet
It includes:
Divided according to Poisson Thiessen polygon, divides the overlay area of each website；Each website constitutes Poisson's point；
In the overlay area of division, the overlay area of the first object website is determined.
8. the method for claim 7, which is characterized in that each website is the nothing for the low-power disposed towards intensive small station
Line access node；Each website includes at least services sites, first object website and the second targeted sites.
9. the method for claim 7, which is characterized in that measuring and calculating user's covering in the first object website
The movement routine of cover area, comprising:
Determine the moving direction of the user；
According to the moving direction, the motion track of the user is calculated；
Two intersection points for determining the motion track of measuring and calculating and the overlay area of the first object website, between described two intersection points
Motion track constitutes the movement routine.
10. the method as described in claim 3 or 9, which is characterized in that the moving direction includes fixed-direction and on-fixed side
To；
When the moving direction is on-fixed direction, the moving direction of the determination user, comprising:
By interpolation method, interpolation is carried out to the user location that at least two be obtained ahead of time are sequentially arranged, is obtained multinomial
Formula；
According to the polynomial tangent slope, the moving direction is determined.
11. method as claimed in claim 10, which is characterized in that the interpolation method is Lagrange's interpolation；It is described multinomial
Formula is Lagrange interpolation polynomial.
12. the method as described in any one of claim 1-9, which is characterized in that the method also includes:
Power control is carried out to the first object website, or
Shut down the first object website.
13. a kind of website selection device towards the deployment of intensive small station, which is characterized in that described device includes memory and processing
Device, the memory are stored with the website towards the deployment of intensive small station and select computer program；The processor executes the meter
When calculation machine program, to realize such as the step of any one of claim 1-12 the method.
14. a kind of computer readable storage medium, which is characterized in that the storage medium is stored with towards the deployment of intensive small station
Website selects computer program；When the computer program is executed by least one processor, to realize such as claim 1-12
Any one of the method the step of.
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Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE60204381D1 (en) * | 2001-03-26 | 2005-07-07 | Ntt Docomo Inc | Method and device for handover control, and mobile communication system |
| CN102026232A (en) * | 2010-09-29 | 2011-04-20 | 新邮通信设备有限公司 | Cooperative measurement and switching setting optimization method among multiple cells in mobile communication network |
| CN102958123A (en) * | 2011-08-30 | 2013-03-06 | 阿尔卡特朗讯公司 | Method, wireless communication system and device for switching mobile terminal into target cell |
| CN103004257A (en) * | 2011-07-21 | 2013-03-27 | 华为技术有限公司 | Method and device for target cell prediction |
| CN103796268A (en) * | 2014-01-14 | 2014-05-14 | 北京邮电大学 | Network switch control method and device |
| CN103874149A (en) * | 2012-12-10 | 2014-06-18 | 索尼公司 | Mobile switching management method, equipment and system in wireless communication network |
| CN107302778A (en) * | 2017-08-23 | 2017-10-27 | 河海大学常州校区 | A kind of vertically downward switch determining method between macro base station and Home eNodeB |
-
2017
- 2017-08-02 CN CN201710651612.0A patent/CN109391897A/en not_active Withdrawn
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE60204381D1 (en) * | 2001-03-26 | 2005-07-07 | Ntt Docomo Inc | Method and device for handover control, and mobile communication system |
| CN102026232A (en) * | 2010-09-29 | 2011-04-20 | 新邮通信设备有限公司 | Cooperative measurement and switching setting optimization method among multiple cells in mobile communication network |
| CN103004257A (en) * | 2011-07-21 | 2013-03-27 | 华为技术有限公司 | Method and device for target cell prediction |
| CN102958123A (en) * | 2011-08-30 | 2013-03-06 | 阿尔卡特朗讯公司 | Method, wireless communication system and device for switching mobile terminal into target cell |
| CN103874149A (en) * | 2012-12-10 | 2014-06-18 | 索尼公司 | Mobile switching management method, equipment and system in wireless communication network |
| CN103796268A (en) * | 2014-01-14 | 2014-05-14 | 北京邮电大学 | Network switch control method and device |
| CN107302778A (en) * | 2017-08-23 | 2017-10-27 | 河海大学常州校区 | A kind of vertically downward switch determining method between macro base station and Home eNodeB |
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