CN104602338A - Anchor point-based positioning method and device - Google Patents

Abstract

The invention provides an anchor point-based positioning method and device. The method comprises the following steps: acquiring a WIFI (Wireless Fidelity) signal set acquired by a to-be-positioned terminal and an anchor point set of the to-be-positioned terminal when receiving a positioning request transmitted by the to-be-positioned terminal, wherein the anchor point set of the to-be-positioned terminal comprises all anchor points which can receive an identity label of the to-be-positioned terminal; determining a position of the to-be-positioned terminal within a preset region range according to the WIFI signal set acquired by the to-be-positioned terminal, the anchor point set of the to-be-positioned terminal and an established fingerprint library, wherein information stored in the fingerprint library comprises the anchor point set of a test terminal, and the anchor point set of the test terminal comprises all the anchor points which can receive the identity label of the test terminal at any preset sample point position. The problem of positioning drift existing in the prior art can be avoided, and further the accuracy for terminal positioning is improved.

Description

A kind of localization method based on anchor point and device

Technical field

The present invention relates to terminal positioning technical field, particularly relate to a kind of localization method based on anchor point and device.

Background technology

Positional information plays important role in daily life, and its importance obtains great embodiment in personal management and location etc., and people also constantly strengthen for the demand of indoor positioning thereupon.Along with the fast development of WIFI (Wireless Fidelity, WLAN (wireless local area network)) technology, realize the major way location of target become in current indoor location technology based on WiFi technology.

Existing WIFI indoor positioning technologies, usually according to the WIFI signal group that mobile terminal collects, completes the inquiry to this mobile terminal present position from set up fingerprint base.But in the prior art because the motion of human body, the existence of shelter or router transmitting power such as to be undergone mutation at the existence of situation, then may cause drifting about to the position location of this mobile terminal, and then cannot the position residing for this mobile terminal be located accurately.

Concrete, as shown in Figure 1, suppose that the WIFI signal group that fingerprint base mid point a is corresponding is { (MAC1, VALUE1), (MAC2, VALUE2), (MAC3, VALUE3) }, the WIFI signal group putting b corresponding is { (MAC1, VALUE1), (MAC2, VALUE2+ Δ V), (MAC3, VALUE3) }.When mobile terminal is positioned at a some b, due to occur the motion of human body, the existence of shelter or router transmitting power to undergo mutation etc. situation impact under, mobile terminal is made to be { (MAC1 in the WIFI signal group that a b collects, VALUE1). (MAC2, VALUE2). (MAC3, VALUE3) }, so according to the record case in fingerprint base, the position location corresponding to this mobile terminal is for some a instead of put b.

Summary of the invention

The invention provides a kind of localization method based on anchor point and device, in order to solve location drifting problem existing when positioning terminal in prior art.

A kind of localization method based on anchor point that the embodiment of the present invention provides, be provided with anchor point within the scope of predeterminable area, described anchor point can receive the identify label of the terminal being positioned at this anchor point coverage, and the method comprises:

Receive terminal to be positioned when sending Location Request, obtain the collection of anchors of WIFI signal group that described terminal to be positioned collects and described terminal to be positioned, the collection of anchors of described terminal to be positioned comprises whole anchor points that can receive described terminal identity mark to be positioned;

According to WIFI signal group, the described collection of anchors of terminal to be positioned and the fingerprint base of foundation that described terminal to be positioned collects, determine the described position of terminal to be positioned within the scope of described predeterminable area, the information that described fingerprint base stores comprises the collection of anchors of test terminal, and the collection of anchors of described test terminal is included in all anchor points that arbitrary default sampling point position can receive test terminal identify label.

In described method, described fingerprint base is set up according to the sample information presetting sampling point position, specifically comprises:

Obtain the WIFI signal group that test terminal collects in arbitrary described sampling point position, and receive all anchor points of the identify label of described test terminal in this sampling point position;

All anchor point composition collection of anchors of the identify label of described test terminal will be received in this sampling point position;

Using the coordinate of this sampling point position, WIFI signal group that test terminal collects in this sampling point position and receive the identify label of described test terminal in this sampling point position collection of anchors as a WIFI fingerprint, and stored in described fingerprint base.

Embodiments provide a kind of method preferably setting up fingerprint base.

In described method, according to WIFI signal group, the described collection of anchors of terminal to be positioned and the fingerprint base of foundation that described terminal to be positioned collects, determine the described position of terminal to be positioned within the scope of described predeterminable area, specifically comprise:

All WIFI fingerprints comprising the collection of anchors of described terminal to be positioned are filtered out, the WIFI fingerprint group after composition screening from described fingerprint base;

According to the WIFI signal group that terminal to be positioned collects, and screening after WIFI fingerprint group in WIFI signal group and sampling point position, set up probabilistic model;

According to the probabilistic model set up, calculate the posterior probability of each sampling point position in the WIFI fingerprint group of described terminal to be positioned after screening;

According to the coordinate of the described posterior probability calculated and sampling point position, determine the coordinate of described terminal to be positioned within the scope of described predeterminable area.

When utilizing the WIFI fingerprint group after screening to calculate the position of terminal to be positioned within the scope of predeterminable area, reduce computer capacity, improve computational efficiency.

In described method, the computing formula of described posterior probability is:

$P\left(L_i\right|S)=\frac{P\left(S\right|L_i)\×P\left(L_i\right)}{P\left(S\right)}$

Wherein, L _ifor arbitrary sampling point position in the WIFI fingerprint group after screening, S is the WIFI signal group that described terminal to be positioned collects; P (L _i| S) be the posterior probability of arbitrary sampling point position in the WIFI fingerprint group of described terminal to be positioned after screening; P (S|L _i) for WIFI signal group corresponding to arbitrary sampling point position in the WIFI fingerprint group after screening be the probability of S; P (L _i) probability that occurs for sampling point position arbitrary in the WIFI fingerprint group of described terminal to be positioned after screening; P (S) for WIFI signal group that sampling point positions all in the WIFI fingerprint group of described terminal to be positioned after screening is corresponding be the probability sum of S.

In described method, the coordinate of the described posterior probability that described basis calculates and sampling point position, determine the coordinate of described terminal to be positioned within the scope of described predeterminable area, specifically comprise:

Using the weights of the posterior probability of each sampling point position in the WIFI fingerprint group of described terminal to be positioned after screening as this sampling point position coordinates;

By the coordinate weighted sum of each sampling point position in the WIFI fingerprint group after screening, obtain the coordinate of described terminal to be positioned within the scope of described predeterminable area;

The computing formula of the coordinate of described terminal to be positioned within the scope of described predeterminable area (x, y, z) is as follows:

$(x,y,z)=\underset{i=0}{\overset{m}{\mathrm{\Σ}}}P\left(\mathrm{Li}\right|S)\×(x_i,y_i,z_i)$

Wherein, m represents the number of WIFI fingerprint in the WIFI fingerprint group after screening, and i represents the arbitrary sampling point position in the WIFI fingerprint group after screening, (x _i, y _i, z _i) represent the coordinate of arbitrary sampling point position in the WIFI fingerprint group after screening.

Utilize the embodiment of the present invention, the position of the terminal to be positioned calculated can be made more accurate.

Present invention also offers a kind of positioner based on anchor point, be provided with anchor point within the scope of predeterminable area, described anchor point can receive the identify label of the terminal being positioned at this anchor point coverage, and this device comprises:

Acquiring unit, for receive terminal to be positioned send Location Request time, obtain the collection of anchors of WIFI signal group that described terminal to be positioned collects and described terminal to be positioned, the collection of anchors of described terminal to be positioned comprises whole anchor points that can receive described terminal identity mark to be positioned;

Determining unit, for the WIFI signal group collected according to described terminal to be positioned, the described collection of anchors of terminal to be positioned and the fingerprint base of foundation, determine the described position of terminal to be positioned within the scope of described predeterminable area, the information that described fingerprint base stores comprises the collection of anchors of test terminal, and the collection of anchors of described test terminal is included in all anchor points that arbitrary default sampling point position can receive test terminal identify label.

Preferably, this device also comprises:

Setting up unit, for obtaining the WIFI signal group that test terminal collects in arbitrary described sampling point position, and receiving all anchor points of the identify label of described test terminal in this sampling point position;

All anchor point composition collection of anchors of the identify label of described test terminal will be received in this sampling point position;

Using the coordinate of this sampling point position, WIFI signal group that test terminal collects in this sampling point position and receive the identify label of described test terminal in this sampling point position collection of anchors as a WIFI fingerprint, and stored in described fingerprint base.

Preferably, the determining unit in this device specifically for:

All WIFI fingerprints comprising the collection of anchors of described terminal to be positioned are filtered out, the WIFI fingerprint group after composition screening from described fingerprint base;

According to the WIFI signal group that terminal to be positioned collects, and screening after WIFI fingerprint group in WIFI signal group and sampling point position, set up probabilistic model;

According to the probabilistic model set up, calculate the posterior probability of each sampling point position in the WIFI fingerprint group of described terminal to be positioned after screening;

According to the coordinate of the described posterior probability calculated and sampling point position, determine the coordinate of described terminal to be positioned within the scope of described predeterminable area.

Preferably, in this device determining unit specifically for, adopt posterior probability described in following formulae discovery:

$P\left(L_i\right|S)=\frac{P\left(S\right|L_i)\×P\left(L_i\right)}{P\left(S\right)}$

Wherein, L _ifor arbitrary sampling point position in the WIFI fingerprint group after screening, S is the WIFI signal group that described terminal to be positioned collects; P (L _i| S) be the posterior probability of arbitrary sampling point position in the WIFI fingerprint group of described terminal to be positioned after screening; P (S|L _i) for WIFI signal group corresponding to arbitrary sampling point position in the WIFI fingerprint group after screening be the probability of S; P (L _i) probability that occurs for sampling point position arbitrary in the WIFI fingerprint group of described terminal to be positioned after screening; P (S) for WIFI signal group that sampling point positions all in the WIFI fingerprint group of described terminal to be positioned after screening is corresponding be the probability sum of S.

Preferably, in this device determining unit specifically for:

Using the weights of the posterior probability of each sampling point position in the WIFI fingerprint group of described terminal to be positioned after screening as this sampling point position coordinates;

By the coordinate weighted sum of each sampling point position in the WIFI fingerprint group after screening, obtain the coordinate of described terminal to be positioned within the scope of described predeterminable area;

The computing formula of the coordinate of described terminal to be positioned within the scope of described predeterminable area (x, y, z) is as follows:

$(x,y,z)=\underset{i=0}{\overset{m}{\mathrm{\Σ}}}P\left(\mathrm{Li}\right|S)\×(x_i,y_i,z_i)$

Wherein, m represents the number of WIFI fingerprint in the WIFI fingerprint group after screening, and i represents the arbitrary sampling point position in the WIFI fingerprint group after screening, (x _i, y _i, z _i) represent the coordinate of arbitrary sampling point position in the WIFI fingerprint group after screening.

The localization method based on anchor point utilizing the embodiment of the present invention to provide and device have following beneficial effect: by arranging multiple anchor point within the scope of predeterminable area, thus predeterminable area is divided into multiple subregion, before determining the position of terminal to be positioned within the scope of predeterminable area, first determine the collection of anchors belonging to this terminal, thus the position of this terminal within the scope of predeterminable area is reduced into the predeterminable area that the collection of anchors belonging to this terminal covers, thus avoid the problem of the location drift existed in prior art, and then the accuracy that improve terminal positioning.

Accompanying drawing explanation

The location schematic diagram that Fig. 1 provides for prior art;

The localization method flow chart based on anchor point that Fig. 2 provides for the embodiment of the present invention;

The predeterminable area that Fig. 3 provides for the embodiment of the present invention and anchor point schematic diagram;

The method flow diagram setting up fingerprint base that Fig. 4 provides for the embodiment of the present invention;

The anchor point setting procedure figure that Fig. 5 provides for the embodiment of the present invention;

The WIFI signal group, the collection of anchors of terminal to be positioned and the fingerprint base of foundation that collect according to terminal to be positioned that Fig. 6 provides for the embodiment of the present invention, determine the method flow diagram of the position of terminal to be positioned within the scope of described predeterminable area;

The positioner schematic diagram based on anchor point that Fig. 7 provides for the embodiment of the present invention.

Embodiment

Below in conjunction with drawings and Examples, the localization method based on anchor point provided by the invention and device are illustrated in greater detail.

The embodiment of the present invention provides a kind of localization method based on anchor point, is provided with anchor point within the scope of predeterminable area, and described anchor point can receive the identify label of the terminal being positioned at this anchor point coverage, as shown in Figure 2, comprising:

Step 101, when receiving the Location Request that terminal to be positioned sends, obtain the collection of anchors of WIFI signal group that terminal to be positioned collects and terminal to be positioned, the collection of anchors of described terminal to be positioned comprises whole anchor points that can receive described terminal identity mark to be positioned.

Concrete, at least one router is had within the scope of predeterminable area, and multiple anchor point is set within the scope of predeterminable area, each anchor point can cover certain limit, the identify label of the signal that the all-router in this anchor point coverage and terminal send and all-router and terminal, can be received by this anchor point, the signal that router outside this anchor point coverage and terminal send, this anchor point cannot receive, preferably, the identify label of terminal is the MAC Address of this terminal, also can be other.

The scope covered between anchor point may have common factor also may not occur simultaneously.Wherein, any corner within the scope of predeterminable area is all covered by anchor point.As shown in Figure 3, rectangular area is predeterminable area scope, and point 1 is anchor point to point 6, and border circular areas is the coverage that each anchor point is corresponding.

Concrete, the any position of terminal within the scope of predeterminable area can receive the WIFI signal that router sends, a WIFI signal comprises: the WIFI signal intensity of this router that the MAC Address of router and terminal receive, WIFI signal group is made up of multiple WIFI signal.Any position of terminal within the scope of predeterminable area only may can receive the WIFI signal that a router sends, also may receive the WIFI signal that multiple router sends, the WIFI signal of all-router terminal any position within the scope of predeterminable area received here forms a WIFI signal group.

The collection of anchors of terminal to be positioned specifically refers to that terminal to be positioned can receive the set of whole anchor points of this terminal identity mark to be positioned in the position at its place.Concrete, this collection of anchors may be made up of multiple anchor point, also may be made up of an anchor point, and specifically comprising how many anchor points in collection of anchors is determined by the anchor point number receiving terminal identity to be positioned mark.Preferably, the corresponding mark of anchor point, collection of anchors is represented by the mark that anchor point is corresponding, such as collection of anchors P={1,2}, wherein 1,2 marks being respectively anchor point.

As shown in Figure 3, collection of anchors belonging to a of position is Pa={1,4}, collection of anchors belonging to the b of position is Pb={3}, visible, utilize the embodiment of the present invention positions different in same setting regions can be divided into less region, and in the localization method of prior art, can only know that position a and position b belongs to room area, further position a and position b can not be divided into less region.

Step 102, according to WIFI signal group, the described collection of anchors of terminal to be positioned and the fingerprint base of foundation that described terminal to be positioned collects, determine the described position of terminal to be positioned within the scope of predeterminable area, the information that described fingerprint base stores comprises the collection of anchors of test terminal, and the collection of anchors of described test terminal is included in all anchor points that arbitrary default sampling point position can receive test terminal identify label.

Concrete, terminal to be positioned is constant in the collection of anchors that current location is corresponding, and the WIFI signal group S gathered in current location is constant, and the current location of terminal to be positioned is the position of terminal to be positioned within the scope of predeterminable area to be determined.Preferably, predeterminable area is room area.

The embodiment of the present invention by arranging multiple anchor point within the scope of predeterminable area, thus predeterminable area is divided into multiple subregion, before determining the position of terminal to be positioned within the scope of predeterminable area, first determine the collection of anchors belonging to this terminal, thus the position of this terminal within the scope of predeterminable area is reduced into the predeterminable area that the collection of anchors belonging to this terminal covers, thus avoid the problem of the location drift existed in prior art, and then improve the accuracy to terminal positioning.

The embodiment of the present invention, within the scope of predeterminable area, router quantity is more, and the positioning result treating locating terminal is more accurate.

Concrete, within the scope of predeterminable area, arrange multiple sampling point position, then described fingerprint base is set up according to the sample information presetting sampling point position, as shown in Figure 4, specifically comprises:

Step 201, obtains the WIFI signal group that test terminal collects in this arbitrary sampling point position, and receives all anchor points of the identify label of described test terminal in this sampling point position;

Step 202, will receive all anchor point composition collection of anchors of the identify label of described test terminal in this sampling point position;

Step 203, using the coordinate of this sampling point position, WIFI signal group that test terminal collects in this sampling point position and receive the identify label of described test terminal in this sampling point position collection of anchors as a WIFI fingerprint, and stored in described fingerprint base.Wherein, the coordinate of sampling point position is the coordinate of this sampling point within the scope of predeterminable area.

All sampling point positions for room area all perform step 201-step 203, by WIFI fingerprint corresponding for all sampling point positions stored in after fingerprint base, obtain fingerprint base.Wherein, by all for a sampling point in office anchor points that can receive test terminal identify label, as the collection of anchors of this sampling point position, the collection of anchors of described test terminal identify label is namely received in this sampling point position.

Wherein, presetting sampling point position comprises multiple, described fingerprint base is made up of multiple WIFI fingerprint, a WIFI fingerprint comprises: within the scope of described predeterminable area collection of anchors corresponding to coordinate corresponding to a sampling point position, this sampling point position, the WIFI signal group corresponding in this sampling point position, this sampling point position, sampling point position coordinates between WIFI fingerprint is different, a coordinate within the scope of a corresponding predeterminable area in sampling point position.

The present embodiment just sets up the one preferably execution mode of fingerprint base, also can set up fingerprint base according to other modes, not limit here.

Preferably, within the scope of predeterminable area, carry out anchor point setting, as shown in Figure 5, specifically comprise:

Step 301, the desired location within the scope of predeterminable area arranges first anchor point;

Step 302, according to the coverage of this anchor point self, detects the marginal position in anchor point self coverage, and whether this anchor point can receive the identify label of test terminal; If so, step 303 is performed; If can not, perform step 304;

Step 303, according to setting step-length, and apart from the coverage edge order from the near to the remote of this anchor point self, successively test terminal is placed on the position outside self coverage of this anchor point, position outside self coverage of this anchor point, when this anchor point can not receive the identify label of test terminal, place second anchor point in this position;

Step 304, places second anchor point at the marginal position of anchor point self coverage.

The method to set up of other anchor point is similar with the method to set up of second anchor point, repeats no more here.

Also can utilize other method that anchor point is set, such as just multiple anchor point is set within the scope of predeterminable area according to the coverage of anchor point self.After anchor point within the scope of predeterminable area is provided with, terminal any position within the scope of predeterminable area sends signal, has at least an anchor point can receive the identify label of this terminal.

Preferably, in a step 102, according to WIFI signal group, the described collection of anchors of terminal to be positioned and the fingerprint base of foundation that described terminal to be positioned collects, the described position of terminal to be positioned within the scope of described predeterminable area is determined, as shown in Figure 6, specifically comprise:

Step 401, filters out all WIFI fingerprints comprising the collection of anchors of described terminal to be positioned from described fingerprint base, the WIFI fingerprint group after composition screening.

Step 402, according to the WIFI signal group that terminal to be positioned collects, and screening after WIFI fingerprint group in WIFI signal group and sampling point position, set up probabilistic model.

Step 403, according to the probabilistic model set up, calculates the posterior probability of each sampling point position in the WIFI fingerprint group of described terminal to be positioned after screening.

Step 404, according to the coordinate of the described posterior probability calculated and sampling point position, determines the coordinate of described terminal to be positioned within the scope of described predeterminable area.

Concrete, according to the collection of anchors P of terminal to be positioned belonging to current location, all collection of anchors identical with this collection of anchors P are filtered out from fingerprint base, namely all WIFI fingerprints comprising the collection of anchors P of terminal to be positioned in fingerprint base are filtered out, WIFI fingerprint group after composition screening, thus when calculating the position of terminal to be positioned within the scope of predeterminable area (current location), reducing computer capacity, and then improve computational efficiency.

Concrete, according to the WIFI signal group that terminal to be positioned collects in step 402, and screening after WIFI fingerprint group in WIFI signal group and sampling point position, set up in probabilistic model, the foundation of probabilistic model according to existing algorithm realization, can not limit here.

Concrete, in step 403, in the WIFI fingerprint group of terminal to be positioned after screening, the posterior probability of each sampling point position refers to: when the WIFI signal group that terminal to be positioned collects is S, the position of terminal to be positioned within the scope of predeterminable area is the probability of the arbitrary sampling point position in the WIFI fingerprint group after screening, this posterior probability P (L _i| S) computing formula as follows:

$P\left(L_i\right|S)=\frac{P\left(S\right|L_i)\×P\left(L_i\right)}{P\left(S\right)}$

Wherein, L _irepresent arbitrary sampling point position in the WIFI fingerprint group after screening, S is the WIFI signal group that terminal to be positioned collects, P (S|L _i) for WIFI signal group corresponding to arbitrary sampling point position in the WIFI fingerprint group after screening be the probability of S, P (L _i) probability that occurs for sampling point position arbitrary in the WIFI fingerprint group of terminal to be positioned after screening, P (S) for WIFI signal group that sampling point positions all in the WIFI fingerprint group of terminal to be positioned after screening is corresponding be the probability sum of S.

Wherein, in fingerprint base, the sampling point place of each WIFI fingerprint can collect a WIFI signal group.

Concrete, P (L _i) account form as follows:

wherein, 0≤i≤m, m represents the number of WIFI fingerprint in the WIFI fingerprint group after screening.

Suppose that WIFI signal group S is { s ₁, s ₂..., s _j... s _n, wherein, s _jrepresent the WIFI signal intensity of the router j that terminal to be positioned arrives in the station acquisition at its place, n represents the number (number of router) that in WIFI signal group S, signal is strong, P (S|L _i) account form as follows:

P (S|L _i)=Π P (s _j| L _i), wherein, 0≤i≤m, 0≤j≤n, m represents the number of WIFI fingerprint in the WIFI fingerprint group after screening, P (s _j| L _i) represent screening after WIFI fingerprint group in the WIFI signal intensity of router j that collects of sampling point position i be s _jprobability.

Concrete, the account form of P (S) is as follows:

$P\left(S\right)=\underset{i=0}{\overset{m}{\mathrm{\Σ}}}P\left(S\right|L_i)\×P\left(L_i\right)$

Concrete, above-mentioned P (s _j| L _i) computing formula as follows:

$P\left(s_j\right|L_i)=\frac{1}{\sqrt{2\mathrm{\π}}\·{\mathrm{\δ}}_j}{e}^{-\frac{{(s_j-{\mathrm{\μ}}_j)}^2}{2{{\mathrm{\δ}}_j}^2}}$

Wherein, s _jrepresent the WIFI signal intensity of the router j that terminal to be positioned arrives in the station acquisition at its place, μ _jrepresent the average of the signal strength signal intensity of router j in the WIFI signal group S' that in the WIFI fingerprint group after screening, sampling point position i is corresponding, δ _jrepresent the variance of the signal strength signal intensity of router j in the WIFI signal group S' that in the WIFI fingerprint group after screening, sampling point position i is corresponding.

Concrete body, when setting up fingerprint base, testing equipment carries out multi collect when the signal strength signal intensity of each router of each sampling point station acquisition, then calculate average and the variance of this router signal strength signal intensity corresponding in this sampling point position to the signal strength signal intensity of this router according to multi collect, suppose, for arbitrary sampling point position, the signal strength signal intensity of the arbitrary router of multi collect is respectively: { sig ₁, sig ₂..., sig _k..., sig _q, wherein, q represents the number of times of the signal strength signal intensity at the arbitrary router of same sampling point station acquisition, then average μ account form is:

$\mathrm{\μ}=\frac{\underset{k=1}{\overset{q}{\mathrm{\Σ}}}\mathrm{si}{g}_k}{q}$

The account form of variance δ is:

$\mathrm{\δ}=\sqrt{\frac{\underset{k=1}{\overset{q}{\mathrm{\Σ}}}{({\mathrm{sig}}_k-\mathrm{\μ})}^2}{q}}$

In step 404, according to the coordinate of the described posterior probability calculated and sampling point position, determine the coordinate of described terminal to be positioned within the scope of described predeterminable area, specifically comprise:

Using the weights of the posterior probability of each sampling point position in the WIFI fingerprint group of described terminal to be positioned after screening as this sampling point position coordinates;

By the coordinate weighted sum of each sampling point position in the WIFI fingerprint group after screening, obtain the coordinate of described terminal to be positioned within the scope of described predeterminable area;

The computing formula of the coordinate of described terminal to be positioned within the scope of described predeterminable area (x, y, z) is as follows:

$(x,y,z)=\underset{i=0}{\overset{m}{\mathrm{\Σ}}}P\left(\mathrm{Li}\right|S)\×(x_i,y_i,z_i)$

Wherein, m represents the number of WIFI fingerprint in the WIFI fingerprint group after screening, and i represents the arbitrary sampling point position in the WIFI fingerprint group after screening, (x _i, y _i, z _i) represent the coordinate of arbitrary sampling point position in the WIFI fingerprint group after screening.

Concrete, the coordinate of any position within the scope of predeterminable area can be expressed as (x, y, z), wherein x, y represent that terminal is at the abscissa of predeterminable area and ordinate respectively, when described predeterminable area is room area, z represents the layer that terminal is positioned at, and namely when room area is divided into multilayer in the vertical direction, z represents wherein any layer.

Corresponding P (the L in each sampling point position _i| S), the P (L that in the WIFI fingerprint group after screening, all sampling point positions are corresponding _i| S) as the weights of this position sampling point coordinate, by all positions sampling point coordinate weighted sum in the WIFI fingerprint group after screening, obtain the coordinate of terminal to be positioned within the scope of predeterminable area, that is, the position of terminal to be positioned within the scope of predeterminable area.

Present invention also offers a kind of positioner based on anchor point, as shown in Figure 7, be provided with anchor point within the scope of predeterminable area, described anchor point can receive the identify label of the terminal being positioned at this anchor point coverage, and this device comprises:

Acquiring unit 501, for receive terminal to be positioned send Location Request time, obtain the collection of anchors of WIFI signal group that described terminal to be positioned collects and described terminal to be positioned, the collection of anchors of described terminal to be positioned comprises whole anchor points that can receive described terminal identity mark to be positioned;

Determining unit 502, for the WIFI signal group collected according to described terminal to be positioned, the described collection of anchors of terminal to be positioned and the fingerprint base of foundation, determine the described position of terminal to be positioned within the scope of described predeterminable area, the information that described fingerprint base stores comprises the collection of anchors of test terminal, and the collection of anchors of described test terminal is included in all anchor points that arbitrary default sampling point position can receive test terminal identify label.

Preferably, this device also comprises:

Setting up unit 503, for obtaining the WIFI signal group that test terminal collects in arbitrary described sampling point position, and receiving all anchor points of the identify label of described test terminal in this sampling point position;

All anchor point composition collection of anchors of the identify label of described test terminal will be received in this sampling point position;

Using the coordinate of this sampling point position, WIFI signal group that test terminal collects in this sampling point position and receive the identify label of described test terminal in this sampling point position collection of anchors as a WIFI fingerprint, and stored in described fingerprint base.

Preferably, the determining unit in this device specifically for:

All WIFI fingerprints comprising the collection of anchors of described terminal to be positioned are filtered out, the WIFI fingerprint group after composition screening from described fingerprint base;

According to the WIFI signal group that terminal to be positioned collects, and screening after WIFI fingerprint group in WIFI signal group and sampling point position, set up probabilistic model;

According to the probabilistic model set up, calculate the posterior probability of each sampling point position in the WIFI fingerprint group of described terminal to be positioned after screening;

According to the coordinate of the described posterior probability calculated and sampling point position, determine the coordinate of described terminal to be positioned within the scope of described predeterminable area.

Preferably, in this device determining unit specifically for, adopt posterior probability described in following formulae discovery:

$P\left(L_i\right|S)=\frac{P\left(S\right|L_i)\×P\left(L_i\right)}{P\left(S\right)}$

Wherein, L _ifor arbitrary sampling point position in the WIFI fingerprint group after screening, S is the WIFI signal group that described terminal to be positioned collects; P (L _i| S) be the posterior probability of arbitrary sampling point position in the WIFI fingerprint group of described terminal to be positioned after screening; P (S|L _i) for WIFI signal group corresponding to arbitrary sampling point position in the WIFI fingerprint group after screening be the probability of S; P (L _i) probability that occurs for sampling point position arbitrary in the WIFI fingerprint group of described terminal to be positioned after screening; P (S) for WIFI signal group that sampling point positions all in the WIFI fingerprint group of described terminal to be positioned after screening is corresponding be the probability sum of S.

Preferably, in this device determining unit specifically for:

Using the weights of the posterior probability of each sampling point position in the WIFI fingerprint group of described terminal to be positioned after screening as this sampling point position coordinates;

By the coordinate weighted sum of each sampling point position in the WIFI fingerprint group after screening, obtain the coordinate of described terminal to be positioned within the scope of described predeterminable area;

The computing formula of the coordinate of described terminal to be positioned within the scope of described predeterminable area (x, y, z) is as follows:

$(x,y,z)=\underset{i=0}{\overset{m}{\mathrm{\Σ}}}P\left(\mathrm{Li}\right|S)\×(x_i,y_i,z_i)$

Wherein, m represents the number of WIFI fingerprint in the WIFI fingerprint group after screening, and i represents the arbitrary sampling point position in the WIFI fingerprint group after screening, (x _i, y _i, z _i) represent the coordinate of arbitrary sampling point position in the WIFI fingerprint group after screening.

The localization method based on anchor point utilizing the embodiment of the present invention to provide and device have following beneficial effect: by arranging multiple anchor point within the scope of predeterminable area, thus predeterminable area is divided into multiple subregion, before determining the position of terminal to be positioned within the scope of predeterminable area, first determine the collection of anchors belonging to this terminal, thus the position of this terminal within the scope of predeterminable area is reduced into the predeterminable area that the collection of anchors belonging to this terminal covers, thus avoid the problem of the location drift existed in prior art, and then the accuracy that improve terminal positioning.

The present invention describes with reference to according to the flow chart of the method for the embodiment of the present invention, equipment (system) and computer program and/or block diagram.Should understand can by the combination of the flow process in each flow process in computer program instructions realization flow figure and/or block diagram and/or square frame and flow chart and/or block diagram and/or square frame.These computer program instructions can being provided to the processor of all-purpose computer, special-purpose computer, Embedded Processor or other programmable data processing device to produce a machine, making the instruction performed by the processor of computer or other programmable data processing device produce device for realizing the function of specifying in flow chart flow process or multiple flow process and/or block diagram square frame or multiple square frame.

These computer program instructions also can be stored in can in the computer-readable memory that works in a specific way of vectoring computer or other programmable data processing device, the instruction making to be stored in this computer-readable memory produces the manufacture comprising command device, and this command device realizes the function of specifying in flow chart flow process or multiple flow process and/or block diagram square frame or multiple square frame.

These computer program instructions also can be loaded in computer or other programmable data processing device, make on computer or other programmable devices, to perform sequence of operations step to produce computer implemented process, thus the instruction performed on computer or other programmable devices is provided for the step realizing the function of specifying in flow chart flow process or multiple flow process and/or block diagram square frame or multiple square frame.

Although describe the preferred embodiments of the present invention, those skilled in the art once obtain the basic creative concept of cicada, then can make other change and amendment to these embodiments.So claims are intended to be interpreted as comprising preferred embodiment and falling into all changes and the amendment of the scope of the invention.

Obviously, those skilled in the art can carry out various change and modification to the present invention and not depart from the spirit and scope of the present invention.Like this, if these amendments of the present invention and modification belong within the scope of the claims in the present invention and equivalent technologies thereof, then the present invention is also intended to comprise these change and modification.

Claims (10)

1. based on a localization method for anchor point, it is characterized in that, be provided with anchor point within the scope of predeterminable area, described anchor point can receive the identify label of the terminal being positioned at this anchor point coverage, and the method comprises:

Receive terminal to be positioned when sending Location Request, obtain the collection of anchors of WIFI signal group that described terminal to be positioned collects and described terminal to be positioned, the collection of anchors of described terminal to be positioned comprises whole anchor points that can receive described terminal identity mark to be positioned;

According to WIFI signal group, the described collection of anchors of terminal to be positioned and the fingerprint base of foundation that described terminal to be positioned collects, determine the described position of terminal to be positioned within the scope of described predeterminable area, the information that described fingerprint base stores comprises the collection of anchors of test terminal, and the collection of anchors of described test terminal is included in all anchor points that arbitrary default sampling point position can receive test terminal identify label.

2. the method for claim 1, is characterized in that, described fingerprint base is set up according to the sample information presetting sampling point position, specifically comprises:

Obtain the WIFI signal group that test terminal collects in arbitrary described sampling point position, and receive all anchor points of the identify label of described test terminal in this sampling point position;

All anchor point composition collection of anchors of the identify label of described test terminal will be received in this sampling point position;

Using the coordinate of this sampling point position, WIFI signal group that test terminal collects in this sampling point position and receive the identify label of described test terminal in this sampling point position collection of anchors as a WIFI fingerprint, and stored in described fingerprint base.

3. the method as described in as arbitrary in claim 1-2, it is characterized in that, according to WIFI signal group, the described collection of anchors of terminal to be positioned and the fingerprint base of foundation that described terminal to be positioned collects, determine the described position of terminal to be positioned within the scope of described predeterminable area, specifically comprise:

All WIFI fingerprints comprising the collection of anchors of described terminal to be positioned are filtered out, the WIFI fingerprint group after composition screening from described fingerprint base;

According to the WIFI signal group that terminal to be positioned collects, and screening after WIFI fingerprint group in WIFI signal group and sampling point position, set up probabilistic model;

According to the probabilistic model set up, calculate the posterior probability of each sampling point position in the WIFI fingerprint group of described terminal to be positioned after screening;

According to the coordinate of the described posterior probability calculated and sampling point position, determine the coordinate of described terminal to be positioned within the scope of described predeterminable area.

4. method as claimed in claim 3, it is characterized in that, the computing formula of described posterior probability is:

$P\left(L_i\right|S)=\frac{P\left(S\right|L_i)\×P\left(L_i\right)}{P\left(S\right)}$

Wherein, L _ifor arbitrary sampling point position in the WIFI fingerprint group after screening, S is the WIFI signal group that described terminal to be positioned collects; P (L _i| S) be the posterior probability of arbitrary sampling point position in the WIFI fingerprint group of described terminal to be positioned after screening; P (S|L _i) for WIFI signal group corresponding to arbitrary sampling point position in the WIFI fingerprint group after screening be the probability of S; P (L _i) probability that occurs for sampling point position arbitrary in the WIFI fingerprint group of described terminal to be positioned after screening; P (S) for WIFI signal group that sampling point positions all in the WIFI fingerprint group of described terminal to be positioned after screening is corresponding be the probability sum of S.

5. method as claimed in claim 4, is characterized in that, according to the coordinate of the described posterior probability calculated and sampling point position, determines the coordinate of described terminal to be positioned within the scope of described predeterminable area, specifically comprises:

Using the weights of the posterior probability of each sampling point position in the WIFI fingerprint group of described terminal to be positioned after screening as this sampling point position coordinates;

By the coordinate weighted sum of each sampling point position in the WIFI fingerprint group after screening, obtain the coordinate of described terminal to be positioned within the scope of described predeterminable area;

The computing formula of the coordinate of described terminal to be positioned within the scope of described predeterminable area (x, y, z) is as follows:

$(x,y,z)=\underset{i=0}{\overset{m}{\mathrm{\Σ}}}P\left(\mathrm{Li}\right|S)\×(x_i,y_i,z_i)$

Wherein, m represents the number of WIFI fingerprint in the WIFI fingerprint group after screening, and i represents the arbitrary sampling point position in the WIFI fingerprint group after screening, (x _i, y _i, z _i) represent the coordinate of arbitrary sampling point position in the WIFI fingerprint group after screening.

6. based on a positioner for anchor point, it is characterized in that, be provided with anchor point within the scope of predeterminable area, described anchor point can receive the identify label of the terminal being positioned at this anchor point coverage, and this device comprises:

Acquiring unit, for receive terminal to be positioned send Location Request time, obtain the collection of anchors of WIFI signal group that described terminal to be positioned collects and described terminal to be positioned, the collection of anchors of described terminal to be positioned comprises whole anchor points that can receive described terminal identity mark to be positioned;

Determining unit, for the WIFI signal group collected according to described terminal to be positioned, the described collection of anchors of terminal to be positioned and the fingerprint base of foundation, determine the described position of terminal to be positioned within the scope of described predeterminable area, the information that described fingerprint base stores comprises the collection of anchors of test terminal, and the collection of anchors of described test terminal is included in all anchor points that arbitrary default sampling point position can receive test terminal identify label.

7. device as claimed in claim 6, is characterized in that, also comprise:

Setting up unit, for obtaining the WIFI signal group that test terminal collects in arbitrary described sampling point position, and receiving all anchor points of the identify label of described test terminal in this sampling point position;

All anchor point composition collection of anchors of the identify label of described test terminal will be received in this sampling point position;

Using the coordinate of this sampling point position, WIFI signal group that test terminal collects in this sampling point position and receive the identify label of described test terminal in this sampling point position collection of anchors as a WIFI fingerprint, and stored in described fingerprint base.

8. the device as described in as arbitrary in claim 6-7, is characterized in that, described determining unit specifically for:

All WIFI fingerprints comprising the collection of anchors of described terminal to be positioned are filtered out, the WIFI fingerprint group after composition screening from described fingerprint base;

According to the WIFI signal group that terminal to be positioned collects, and screening after WIFI fingerprint group in WIFI signal group and sampling point position, set up probabilistic model;

According to the probabilistic model set up, calculate the posterior probability of each sampling point position in the WIFI fingerprint group of described terminal to be positioned after screening;

According to the coordinate of the described posterior probability calculated and sampling point position, determine the coordinate of described terminal to be positioned within the scope of described predeterminable area.

9. device as claimed in claim 8, is characterized in that, described determining unit specifically for, adopt posterior probability described in following formulae discovery:

$P\left(L_i\right|S)=\frac{P\left(S\right|L_i)\×P\left(L_i\right)}{P\left(S\right)}$

Wherein, L _ifor arbitrary sampling point position in the WIFI fingerprint group after screening, S is the WIFI signal group that described terminal to be positioned collects; P (L _i| S) be the posterior probability of arbitrary sampling point position in the WIFI fingerprint group of described terminal to be positioned after screening; P (S|L _i) for WIFI signal group corresponding to arbitrary sampling point position in the WIFI fingerprint group after screening be the probability of S; P (L _i) probability that occurs for sampling point position arbitrary in the WIFI fingerprint group of described terminal to be positioned after screening; P (S) for WIFI signal group that sampling point positions all in the WIFI fingerprint group of described terminal to be positioned after screening is corresponding be the probability sum of S.

10. device as claimed in claim 9, is characterized in that, described determining unit specifically for:

Using the weights of the posterior probability of each sampling point position in the WIFI fingerprint group of described terminal to be positioned after screening as this sampling point position coordinates;

By the coordinate weighted sum of each sampling point position in the WIFI fingerprint group after screening, obtain the coordinate of described terminal to be positioned within the scope of described predeterminable area;

The computing formula of the coordinate of described terminal to be positioned within the scope of described predeterminable area (x, y, z) is as follows:

$(x,y,z)=\underset{i=0}{\overset{m}{\mathrm{\Σ}}}P\left(\mathrm{Li}\right|S)\×(x_i,y_i,z_i)$

Wherein, m represents the number of WIFI fingerprint in the WIFI fingerprint group after screening, and i represents the arbitrary sampling point position in the WIFI fingerprint group after screening, (x _i, y _i, z _i) represent the coordinate of arbitrary sampling point position in the WIFI fingerprint group after screening.