WO2014180219A1

WO2014180219A1 - Locating method, device and terminal and computer storage medium

Info

Publication number: WO2014180219A1
Application number: PCT/CN2014/075254
Authority: WO
Inventors: 谢思远; 韦薇; 李伟华
Original assignee: 中兴通讯股份有限公司
Priority date: 2013-10-21
Filing date: 2014-04-14
Publication date: 2014-11-13
Also published as: CN104581931A

Abstract

Disclosed are a locating method, device and terminal and a computer storage medium. The locating method comprises: receiving a locating request sent by a terminal to be located, wherein the locating request comprises a received signal strength indicator (RSSI) value of a wireless access point (AP) around the terminal to be located and a medium access control (MAC) address value (S101); in a pre-established fingerprint database, searching for a fingerprint list which is the same as the MAC address value sent by the terminal to be located (S102); calculating a fingerprint similarity between a fingerprint in the fingerprint list and a fingerprint sent by the terminal to be located, and selecting K fingerprints according to the order from high to low of the similarity (S103); and according to location coordinates of the saved K fingerprints in the fingerprint database, generating a plurality of circumcircles, wherein the coordinate of the circle centre of the minimum circumcircle is the location of the terminal to be located (S104).

Description

Positioning method, device, terminal and computer storage medium

The present invention relates to the field of communication technologies, and in particular, to a positioning method, apparatus, terminal, and computer storage medium. Background technique

With the popularity of location based services (LBS), users are increasingly demanding detailed locations. Although various positioning systems already have high accuracy, in cities, due to environmental comparisons. Complex, there are many buildings, the occlusion phenomenon on the floor is serious, which hinders the transmission of satellite signals. It is difficult for users to obtain accurate position information at any time. The traditional positioning system can no longer meet the needs of users. People urgently need an enhanced indoor Positioning technology for external positioning navigation services.

There are three main methods for current outdoor positioning methods:

1. Traditional positioning method based on Global Positioning System (GPS)

The advantage of GPS positioning is that the satellite coverage is large and the positioning is free. In the actual urban environment, due to the weak GPS signal, in the high-rise environment of the city, the building cannot be penetrated, resulting in inaccurate GPS positioning, sometimes even not searching. To the satellite signal.

2. Location technology based on mobile network

Positioning technology based on mobile network signaling has been in existence for many years. The positioning principle mainly uses cell identification code (Cell-ID), triangulation, time of arrival (TOA), time difference of arrival (TDOA, Time Difference of Arrival), The AA (Arrival of Angle) method is used to estimate the position of the user. The accuracy of these positioning methods can only reach 100 meters, and the base station needs to be modified based on the TOA, TDOA or AOA. to make This is higher and has not been widely applied at present.

3. Location technology based on wireless LAN

The WLAN-based positioning technology mainly includes the following methods: The first is that a wireless terminal with Wi-Fi (Wireless Fidelity) function establishes a connection with a wireless access node (AP, Access Point), The location of the wireless AP is used to estimate the location of the mobile terminal, but the location information of the wireless AP needs to be known in advance. Wi-Fi positioning technology in Google Maps uses this technology to scan wireless AP information and its current location information through a street view car. This method is costly and infringes on personal privacy. The car has now stopped publicly collecting user Wi-Fi. The second type is a fingerprint positioning technology based on Received Signal Strength Indication (RSSI), which requires pre-arranging a Wi-Fi hotspot device in a positioning scenario, and then dividing the grid to measure the signal strength of the positioning scene. The RSSI location fingerprint database estimates the location of the user according to the signal strength received by the user's terminal in the positioning. The positioning accuracy of this method mainly depends on the number of wireless APs and the division of the positioning scene grid. Currently, it is mainly used indoors. Positioning. However, in the outdoor field of the city, due to the limitation of the cost of installing Wi-Fi hotspots, it is difficult to deploy Wi-Fi hotspots in large cities, and the establishment of fingerprint databases is very difficult. This method is difficult to promote.

In the era of mobile Internet, more and more people are using smart terminal devices with Wi-Fi and satellite navigation, and Wi-Fi hotspots in cities have become very popular. Wi-Fi has been widely used in airports, hotels, homes, shopping malls. In places such as shops, it can be said that Wi-Fi information is everywhere in every corner of the city. How to use massive Wi-Fi information to help us better locate it becomes an urgent problem to be solved. Summary of the invention

In view of this, embodiments of the present invention are directed to providing a positioning method, apparatus, terminal, and computer storage medium that can utilize a large amount of Wi-Fi information to better achieve positioning.

To achieve the above objective, the technical solution of the embodiment of the present invention is implemented as follows: An embodiment of the present invention provides a positioning method, where the method includes:

Receiving a positioning request sent by the terminal to be located, where the positioning request includes an RSSI value and a media access control (MAC) address value of the wireless AP around the terminal to be located;

In the pre-established fingerprint database, searching for a fingerprint list with the same MAC address value sent by the terminal to be located;

Calculating a fingerprint similarity between the fingerprint in the fingerprint list and the fingerprint sent by the terminal to be located, and selecting K fingerprints according to the order of similarity from high to low; wherein K is a positive integer;

And generating a plurality of circumscribed circles according to the position coordinates of the K fingerprints stored in the fingerprint database, and determining a center coordinate of the minimum circumscribed circle, wherein a center coordinate of the minimum circumscribed circle is a position of the terminal to be located.

Preferably, the method further comprises establishing a fingerprint database.

Specifically, the establishing a fingerprint database includes:

Receiving, by the user terminal, an RSSI value, a MAC address value, and a longitude value and a latitude value of each current AP;

The RSSI value, the MAC address value, and the longitude value and the latitude value of the current location of each wireless AP are saved as a fingerprint to form a fingerprint database.

Preferably, when the saving is performed, the method further includes:

Calculating the fingerprint _ sent by the user terminal; and the fingerprint similarity with the fingerprint stored in the fingerprint database;

Determine whether the fingerprint similarity is greater than a preset threshold, and if so, combine the two fingerprints; /, into one fingerprint for saving; if not, save two fingerprints separately;

Preferably, the fingerprint similarity of the two fingerprints; / is calculated as:

SIM(f _ij ) = (∑ __ _l W _m )ln ; Where is the similarity of the mth pair of Wi-Fi signal pairs, the Wi-Fi signal pair refers to two fingerprints, two Wi-Fi signals with the same MAC address, and n is the number of Wi-Fi signal pairs; If the MAC address of one of the fingerprints _; or one of the Wi-Fi signals does not exist in the other fingerprint or _;, the Wi-Fi signal and 0 constitute a pair of Wi-Fi signals, and the _m value is 0;

The similarity w of two Wi-Fi signals in a Wi-Fi signal pair is calculated as follows:

Where r and r are the RSSI values of two Wi-Fi signals and wi ₂ respectively.

Preferably, the two fingerprints can be saved by combining the two fingerprints into one fingerprint: f{{rs _x , mac _i )...(rs _n , mac _n ), Ion, lai]

={( ¹ 2 ¹ , +lon ^J )/2, (laf +lat ^J )/2}

Where (r , ma _Cl )...(rs _n ', mac _n Ion', tot' is the RSSI value of the fingerprint, the MAC address value, and the longitude and latitude values of the current position; (rs(, ma _Cl ). ..(rs _n , mac _n lon lat ¹ is the fingerprint f

The RSSI value, the MAC address value, and the longitude and latitude values of the current location.

Preferably, the fingerprint similarity between the fingerprint in the fingerprint list and the fingerprint sent by the terminal to be located is calculated, as follows:

The fingerprint similarity calculation formula of the fingerprint in the fingerprint list and the fingerprint sent by the terminal to be located is:

SIM(f _{i ]} ) = (∑ __ _l W _m )ln; where is the similarity of the mth pair of Wi-Fi signal pairs, the Wi-Fi signal pair refers to two fingerprints _;, the two MAC addresses are the same Wi-Fi signal, n is the number of Wi-Fi signal pairs; if the MAC address of one of the fingerprints _; or one of the Wi-Fi signals does not exist in another fingerprint or _; 0 constitutes a pair of Wi-Fi signal pairs, the _M value of 0;

The similarity w of the two Wi-Fi signals in the Wi-Fi signal pair is calculated as follows:

w(w ,wL) = -2 ^rH \/2 ^s - Where r and r are the RSSI values of two Wi-Fi signals and wi ₂ respectively.

The embodiment of the invention further provides a positioning device, the device comprising:

The positioning request receiving module is configured to receive a positioning request sent by the terminal to be located, where the positioning request includes an RSSI value and a MAC address value of a wireless AP around the terminal to be located; and the fingerprint list searching module is configured to be in a pre-established fingerprint Searching, in the database, a fingerprint list with the same MAC address value sent by the terminal to be located;

The fingerprint selection module is configured to calculate a fingerprint similarity between the fingerprint in the fingerprint list and the fingerprint sent by the terminal to be located, and select K fingerprints according to the order of similarity from high to low; wherein K is a positive integer;

a positioning module, configured to generate a plurality of circumscribed circles according to position coordinates of the K fingerprints stored in the fingerprint database, and determine a center coordinate of the minimum circumscribed circle, wherein a center coordinate of the minimum circumscribed circle is a terminal to be located s position.

Preferably, the device further includes a fingerprint database establishing module, which is specifically configured to: receive an RSSI value, a MAC address value, and a longitude value and a latitude value of a current location of each wireless AP obtained by the user terminal;

Preferably, the fingerprint database establishing module is further configured as follows:

Calculate the fingerprint similarity of two fingerprints, f by the following formula: SIM(f _ij ) = (∑" _m __ ₁ W /n;

Where is the similarity of the mth pair of Wi-Fi signal pairs, the Wi-Fi signal pair refers to two fingerprints _;, two Wi-Fi signals with the same MAC address, and n is the number of Wi-Fi signal pairs If the MAC address of one of the fingerprints _; or one of the Wi-Fi signals does not exist in the other fingerprint or _;, the Wi-Fi signal and 0 constitute a pair of Wi-Fi signals, and the _M value is 0;

Where r and r are the RSSI values of two Wi-Fi signals and wi ₂ respectively.

The two fingerprints are merged into one fingerprint by the following formula:

/{(rs^ mac _i )...(rs _n , mac _n ), Ion, lai]

={( ¹ 2 ¹ , +lon ^J )/2, (laf +lat ^J )/2}

Where (r , ma _Cl )...(rs _n ^l , mac _n \ lon tot' is the RSSI value of the fingerprint _; the MAC address value and the longitude and latitude values of the current position; (rs(, ma _Cl ). ..(rs _n , mac _n lon is the RSSI value of the fingerprint f, the MAC address value, and the longitude and latitude values of the current position.

Preferably, the fingerprint selection module is further configured to:

The fingerprint similarity between the fingerprint in the fingerprint list and the fingerprint sent by the terminal to be located is calculated by the following formula:

SIM(f _{i ]} ) = (∑ __ _l W _m )ln;

Wherein, the similarity of the mth pair of Wi-Fi signal pairs, the Wi-Fi signal pair refers to two fingerprints; f) the two Wi-Fi signals with the same MAC address, and n is the pair of Wi-Fi signal pairs If the MAC address of one of the fingerprints _; or one of the Wi-Fi signals does not exist in the other fingerprint or _;, the Wi-Fi signal and 0 form a pair of Wi-Fi signals, and the _M value is 0. ;

Where r and r are the RSSI values of the two Wi-Fi signals and wi ₂ respectively.

The embodiment of the invention further provides a terminal, where the terminal includes:

a sending unit, configured to send a positioning request to the positioning device, where the positioning request includes an RSSI value and a MAC address value of the wireless AP around the terminal to be located;

The receiving unit is configured to receive the location information fed back by the positioning device, and display the information. Preferably, the sending unit is further configured to:

The RSSI value and the MAC address value of each of the surrounding wireless APs are transmitted to the positioning device, and the longitude value and the latitude value of the current location.

The embodiment of the invention further provides a computer storage medium, wherein the computer storage medium stores a computer program, and the computer program is used to execute the positioning method described above.

The positioning method, the device, the terminal and the computer storage medium provided by the embodiments of the present invention make full use of the existing mobile internet and Wi-Fi hotspot information to construct a fingerprint database, and pass the RSSI value and the MAC address value reported by the user terminal. The fingerprint similarity is calculated, and the circumscribed circle is constructed for positioning, which has the advantages of high positioning accuracy, low cost, and stable positioning. DRAWINGS

1 is a flowchart of a positioning method according to an embodiment of the present invention;

2 is a schematic diagram of determining a position of a terminal to be positioned by using a minimum circumscribed circle according to an embodiment of the present invention; FIG. 3 is a schematic structural diagram of a positioning apparatus according to an embodiment of the present invention;

4 is a schematic structural diagram of another positioning device according to an embodiment of the present invention;

FIG. 5 is a schematic diagram of positioning in an actual application provided by an embodiment of the present invention; FIG.

FIG. 6 is a flowchart of positioning in an actual application provided by an embodiment of the present invention. detailed description

The present invention will be further described in detail below in conjunction with the drawings and embodiments. It is understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

As shown in FIG. 1 , an embodiment of the present invention relates to a positioning method, where the method includes: Step S101: Receive a positioning request sent by a terminal to be located, where the positioning request includes an RSSI value of a wireless AP around a terminal to be located. MAC address value.

In this step, the terminal to be located sends a positioning request to the positioning device through the communication network, and simultaneously scans the surrounding wireless AP information (RSSI value and MAC value), and adds all the acquired wireless AP information to the positioning request, and sends the positioning information to the positioning device. The data format of the positioning request may be:

AP{(rs _l , mac^), (rs ₂ , mac ₂ )...(rs _p , mac _p )}.

Where p is the number of wireless APs acquired by the terminal to be located.

Step S102: In the pre-established fingerprint database, search for a fingerprint list with the same MAC address value sent by the terminal to be located.

In this step, according to the positioning request sent by the user, the related fingerprint is retrieved in the fingerprint database, and the fingerprint database contains the fingerprint list of the MAC address in the positioning request in the fingerprint database, that is:

Mac _x OR mac ₂ OR mac ₃ OR ... mac _n ;

Wherein the "OR" represents a logical or symbol.

Specifically, the fingerprint list may include one or more fingerprints.

Step S103: Calculate the similarity between the fingerprint in the fingerprint list and the fingerprint sent by the terminal to be located, and select K fingerprints according to the order of similarity from high to low.

Here, the K is a positive integer.

In this step, the two fingerprints; / / fingerprint similarity calculation formula is:

SIM(f _i ,f _j ) = (∑" _m __ ₁ W /n ; ( 1 ) Where is the similarity of the mth pair of Wi-Fi signal pairs, the Wi-Fi signal pair refers to two fingerprints _;, two Wi-Fi signals with the same MAC address, and n is the number of Wi-Fi signal pairs If the MAC address of one of the fingerprints _; or one of the Wi-Fi signals does not exist in the other fingerprint or _;, the Wi-Fi signal and 0 constitute a pair of Wi-Fi signals, and the _M value is 0;

2 ^rSl - 2 ^rs 2 12" ( 2 ) where , and r are the RSSI values of the two Wi-Fi signals and wi ₂ respectively.

After calculating the similarity of any two fingerprints, K fingerprints are selected in order of similarity from high to low.

Step S104: Generate a plurality of circumscribed circles according to position coordinates of the K fingerprints stored in the fingerprint database, and determine a center coordinate of the minimum circumscribed circle, where the center coordinate of the minimum circumscribed circle is the position of the terminal to be located.

In this step, preferably, the empirical value of K is between 3 and 5. Each fingerprint includes a position coordinate, that is, longitude and latitude. Therefore, each fingerprint is equivalent to one point, and each circumscribed circle can determine a circumcircle, so that a plurality of circumscribed circles can be determined, wherein the minimum circumscribed circle center For the final position of the user terminal to be located, the radius of the circle is a confidence interval, as shown in Figure 2.

In the above steps, the fingerprint database is pre-established, which mainly includes the following steps:

In the first step, the user terminal with the satellite navigation function and the Wi-Fi function scans the wireless APs in the vicinity thereof, and ensures that the number of wireless APs is more than one (including one), and then obtains the RSSI value and the MAC address value of each wireless AP. The satellite longitude and latitude values of the current location are uploaded to the positioning device through the mobile communication network of the user terminal.

Preferably, the uploaded data format is: mac , , (rs _n , mac , Ion, lat}. In the second step, the positioning device performs pre-processing on the fingerprint data uploaded by the user terminal, and completes data uploading and saving, and the specific method is :

The positioning device first preprocesses the uploaded data. Since each Wi-Fi signal has a signal The intensity value can be divided into two categories according to the signal strength, one is a normal signal, and the other is an abnormal signal; due to physical interference, a signal lower than -99dbm or higher than 66dbm is regarded as an abnormal signal, and is rejected. ; Normal signals are saved.

In addition, because a large number of user terminals upload fingerprint data, there may be multiple user terminals uploading the same or similar wireless AP information. If all of the data is not processed, there will be a lot of similar fingerprint data, which will occupy a large amount of data. The storage space is wasteful of storage space. In addition, it is not convenient to quickly retrieve and search the fingerprint list. Therefore, it is also necessary to perform similarity judgment on the fingerprint data uploaded by the user terminal and the data stored in the fingerprint database, and determine the similarity, merge and save, and determine the dissimilarity, and save separately; the specific steps are as follows:

The first step is the similarity calculation.

Since the city-level positioning requires a very dense index, the pressure on the platform server is very large, and the data submitted by the user terminal is largely duplicated, and the index quality needs to be improved. The similarity of two Wi-Fi signals ^, is calculated as follows:

_ 2

Call / 2 ⁸

The formula to be satisfied is that the MAC addresses of the two Wi-Fi signals must be the same. If they are different, the similarity is calculated by 0.

Each time the user terminal uploads information about its neighboring APs, it is recorded as a fingerprint. In a fingerprint data, there is multiple Wi-Fi information. Therefore, the fingerprint sent by the user terminal; and the fingerprint/fingerprint similarity stored in the fingerprint database are calculated as:

SIM(f _{i ]} ) = (∑ __ _l W _m )ln

Where ^ is the similarity of the mth Wi-Fi signal pair in the fingerprint, the Wi-Fi signal pair refers to two fingerprints _;, two Wi-Fi signals with the same MAC address, and n is a Wi-Fi signal pair If the MAC address of one of the fingerprints _; or one of the Wi-Fi signals does not exist in the other fingerprint or _;, the Wi-Fi signal and 0 form a pair of Wi-Fi signals, and the _M value thereof Is 0. If the number of wireless APs in the fingerprint signal uploaded by the user terminal twice before and after the same location changes, that is, some wireless APs in the fingerprint data uploaded by the current user terminal are temporarily turned off, or a part of the wireless AP is newly opened. In the case, it is indicated that there are incompletely matched Wi-Fi signal pairs in the two fingerprint signals, and the n value is the sum of the number of Wi-Fi signal pairs in the two fingerprints and the Wi-Fi number of different MAC addresses.

In the second step, after the user terminal submits the fingerprint data, according to formula (1), the similarity between the fingerprint data uploaded by the user and the fingerprint data stored in the fingerprint database is calculated, and compared with a preset threshold, the threshold can be simulated according to experience and simulation. To set it up, you can also adjust it continuously in the actual application to get the best value. For example, if the threshold is set to 0.97, if the similarity value is higher than 0.97, the two fingerprints are considered to be similar and can be merged with the original fingerprint. Otherwise, it is considered to be dissimilar and needs to be saved separately.

In the third step, the above two similar fingerprints are combined by the average position method, and the position fingerprint database is updated, and the calculation method is as follows:

/{(rs^ mac _i )...(rs _n , mac _n ), Ion, lai]

= {( ¹ 2 ¹ , + lon ^J ) / 2, (laf + lat ^J ) / 2}

Where (r , ma _Cl )...(rs _n ' , mac _n Ion' , tot' are the RSSI value of the fingerprint, the MAC address value, and the longitude and latitude values of the current position; the fingerprint; can be regarded as the original fingerprint The saved fingerprint in the database; (rs( , ma _Cl )...(rs _n , mac _n lon lat ¹ is the RSSI value of the fingerprint, the MAC address value, and the longitude and latitude values of the current position; the fingerprint/can be regarded as Is the fingerprint submitted by the user terminal.

Save the merged fingerprint to the fingerprint database; update the fingerprint database. In particular, if the MAC values of two similar fingerprints do not match exactly, you need to perform the processing in the first step, as shown in the following example:

The fingerprint in the original fingerprint database is:

{( 20, 4437E657F0A2 ), ( 50, 1134E657F1A3 ), ( 80, 3312E658FBA1 )} The user terminal uploads the fingerprint as: {( 10, 4437E657F0A2 ), ( 30, 1134E657F1A3 ), ( 60 , 3142EA58FAA1 )} The fingerprint update algorithm should have a value of 4, and the update formula is:

{ ( (20+10)/2, 4437E657F0A2 ), ( (50+30)/2, 1134E657F1A3 ), ( 80/2, 3312E658FBA1 ), ( 60/2, 3142EA58FAA1 ) }.

In addition, as shown in FIG. 3, an embodiment of the present invention further relates to a positioning apparatus for implementing the foregoing method, including:

The location request receiving module 301 is configured to receive a location request sent by the terminal to be located, where the location request includes an RSSI value and a MAC address value of a wireless AP around the terminal to be located; and the fingerprint list search module 302 is configured to be pre-established. In the fingerprint database, searching for a fingerprint list with the same MAC address value sent by the terminal to be located;

The fingerprint selection module 303 is configured to calculate a fingerprint similarity between the fingerprint in the fingerprint list and the fingerprint sent by the terminal to be located, and select K fingerprints according to the order of similarity from high to low; wherein K is a positive integer;

The positioning module 304 is configured to generate a plurality of circumscribed circles according to position coordinates of the K fingerprints stored in the fingerprint database, and determine a center coordinate of a minimum circumscribed circle, where a center coordinate of the minimum circumscribed circle is to be located The location of the terminal.

As shown in FIG. 4, the positioning device further includes a fingerprint database establishing module 305, which is specifically configured to: receive an RSSI value, a MAC address value, and a longitude value and a latitude value of a current location of each wireless AP obtained by the user terminal;

Preferably, the fingerprint database establishing module 305 is further configured to:

Determine whether the fingerprint similarity of fingerprint, f is greater than a preset threshold, and if so, Two fingerprints; / are merged into one fingerprint for saving; if not, two fingerprints are saved separately;

Calculated by the following equation two fingerprints, fingerprint similarity _7:

The two fingerprints L, / are combined into one fingerprint for saving by the following formula:

/{(rs^ mac _i )...(rs _n , mac _n ), Ion, lai]

={( ¹ 2 ¹ , +lon ^J )/2, (laf +lat ^J )/2}

Where (r , ma _Cl )...(rs _n ^l , mac _n lori , tot' is the RSSI value of the fingerprint f!, the MAC address value, and the longitude and latitude values of the current position; (rs(, ma _Cl ) ...(rs _n , mac _n Ion) , lat ¹ is the RSSI value of the fingerprint, the MAC address value, and the longitude and latitude values of the current location.

The fingerprint selection module 303 is further configured to:

The fingerprint similarity between the fingerprint in the fingerprint list and the fingerprint sent by the terminal to be located is calculated by the following calculation formula:

SIM(f _{i ]} ) = (∑ __ _l W _m )ln; where is the similarity of the mth pair of Wi-Fi signal pairs, the Wi-Fi signal pair refers to two fingerprints _;, the two MAC addresses are the same Wi-Fi signal, n is the number of Wi-Fi signal pairs; if the MAC address of one of the fingerprints _; or one of the Wi-Fi signals does not exist in another fingerprint or _; In the case, the Wi-Fi signal and 0 constitute a pair of Wi-Fi signal pairs, and the _M value is 0;

w(wi _l , wi ₂ ) = l - - 2 ^rH \ / 2 ^s

In an actual application, the positioning request receiving module 301, the fingerprint list searching module 302, the fingerprint selecting module 303, the positioning module 304, and the fingerprint database establishing module 305 may be an application processor or a central processing unit (CPU) in a device or a server to which the positioning device belongs. , Central Processing Unit), Digital Signal Processor (DSP) or Field Programmable Gate Array (FPGA).

In addition, an embodiment of the present invention further relates to a terminal, where the terminal includes:

Here, the terminal may be a mobile phone, a tablet computer, a laptop computer, a navigation device, or the like. In a practical application, the sending unit and the receiving unit may be implemented by an application processor, a CPU, a DSP or an FPGA in the terminal; the sending unit may also be implemented by a transmitter, and the receiving unit may also be implemented by a receiver.

The embodiment of the present invention further describes a computer storage medium, wherein the computer storage medium stores a computer program, and the computer program is used to execute the positioning method shown in FIG. 1 in the embodiment of the present invention.

FIG. 5 is a schematic diagram of positioning in an actual application according to an embodiment of the present invention. As shown in FIG. 5, a mobile terminal has a GPS positioning function and supports a Wi-Fi function, and the mobile terminal will acquire the same. The RSSI value, the MAC address value of each surrounding wireless AP, and the longitude and latitude values of the current location are sent to the fingerprint database, and when the mobile terminal is in an environment without GPS signals or poor GPS signals, the positioning may be sent to the positioning device. The requesting device may return a positioning result to the mobile terminal according to the fingerprint data information stored in the fingerprint database.

FIG. 6 is a flowchart of positioning in an actual application according to an embodiment of the present invention. As shown in FIG. 6, a user terminal having a satellite navigation function and a Wi-Fi function scans a wireless AP in the vicinity thereof, and ensures that the number of wireless APs is one. The above (including one), and then obtaining the RSSI value, the MAC address value of each wireless AP, and the satellite longitude and latitude values of the current location, and uploading the fingerprint and location information to the positioning device through the mobile communication network of the user terminal; the positioning device to the user terminal The uploaded fingerprint data is pre-processed, and the data is uploaded and saved. The positioning terminal sends a positioning request to the positioning device, and the positioning device returns the positioning result to the terminal to be located according to the saved fingerprint data.

In summary, the embodiment of the present invention fully utilizes the existing mobile internet and Wi-Fi hotspot information to construct a fingerprint database, and constructs a circumscribed circle by calculating the fingerprint similarity according to the RSSI value and the MAC address value reported by the user terminal. Positioning has the advantages of high positioning accuracy, low cost, and stable positioning.

While the preferred embodiments of the present invention have been disclosed for purposes of illustration, those skilled in the art will recognize that various modifications, additions and substitutions are possible, and the scope of the invention should not be limited to the embodiments described above. Any modifications, equivalents, and improvements made within the spirit and scope of the present invention are intended to be included within the scope of the present invention. Industrial applicability

In the embodiment of the present invention, the location request sent by the terminal to be located is received; in the fingerprint database that is pre-established, the fingerprint list with the same MAC address value sent by the terminal to be located is searched; the fingerprint in the fingerprint list is calculated and to be determined. a fingerprint similarity of the fingerprint sent by the bit terminal, selecting K fingerprints according to the order of similarity from high to low; generating a plurality of circumscribed circles according to the position coordinates of the K fingerprints stored in the fingerprint database, the minimum circumscribed circle The center coordinates of the circle are to be located The location of the terminal; in this way, it can utilize a large amount of Wi-Fi information to achieve better positioning.

Claims

claims

1. A positioning method, the positioning method includes:

Receive a positioning request sent by the terminal to be located, wherein the positioning request includes the received signal strength indication RSSI value and the medium access control MAC address value of the wireless access node AP around the terminal to be located;

In the pre-established fingerprint database, search for a fingerprint list with the same value as the MAC address sent by the terminal to be located;

Calculate the similarity between the fingerprints in the fingerprint list and the fingerprints sent by the terminal to be located, and select K fingerprints in order from high to low similarity; where K is a positive integer;

According to the position coordinates of K fingerprints saved in the fingerprint database, multiple circumscribed circles are generated, and the center coordinates of the smallest circumscribed circle are determined, where the center coordinates of the smallest circumscribed circle are the positions of the terminals to be located.

2. The positioning method according to claim 1, wherein the method further includes: establishing a fingerprint database;

The establishment of a fingerprint database includes:

Receive the RSSI values, MAC address values of various wireless APs around it obtained by the user terminal, and the longitude and latitude values of the current location;

The RSSI value, MAC address value, and longitude value and latitude value of the current location of each wireless AP are saved as a fingerprint to form a fingerprint database.

3. The positioning method according to claim 2, wherein the saving includes: calculating the fingerprint similarity between the fingerprint sent by the user terminal and the fingerprint saved in the fingerprint database;

Determine whether the fingerprint similarity of fingerprint_;,/ is greater than the preset threshold. If so, merge the two fingerprints;,/ into one fingerprint and save it; if not, save the two fingerprints separately;, f

4. The positioning method according to claim 3, wherein the fingerprint similarity calculation formula of two fingerprints is:

SIM(f _{i ]} ) = (∑ __ _l W _m )ln;

Among them, is the similarity of the m-th wireless fidelity Wi-Fi signal pair, and the Wi-Fi signal pair refers to two fingerprints; , the two Wi-Fi signals with the same MAC address, n is the Wi-Fi signal pair number; If the MAC address of a Wi-Fi signal in fingerprint _; or / does not exist in another fingerprint or f _x , then the Wi-Fi signal and 0 form a Wi-Fi signal pair, and its _M value is 0;

Among them, r and r are the RSSI values of the two Wi-Fi signals and wi ₂ respectively.

5. The positioning method according to claim 3 or 4, wherein two fingerprints are combined into one fingerprint for storage by the following formula:

/{(rs^ mac _i )...(rs _n , mac _n ), Ion, lai]

={( ¹ 2 ¹ , +lon ^J )/2, (laf +lat ^J )/2}

Among them, (r, ma _Cl )...(rs _n ^l , mac _n lori, tot' is the RSSI value, MAC address value of fingerprint f! and the longitude value and latitude value of the current location; (rs(, ma _Cl ) ...(rs _n , mac _n Ion], lat ¹ is the RSSI value of the fingerprint, the MAC address value, and the longitude and latitude values of the current location.

6. The positioning method according to claim 1, wherein the fingerprint similarity between the fingerprints in the fingerprint list and the fingerprints sent by the terminal to be located is calculated, specifically as follows:

The fingerprint similarity calculation formula between the fingerprints in the fingerprint list and the fingerprints sent by the terminal to be located is:

SIM(f _{i ]} ) = (∑ __ _l W _m )ln;

Among them, is the similarity of the m-th Wi-Fi signal pair, and the Wi-Fi signal pair refers to two There are two Wi-Fi signals with the same MAC address in fingerprint_;, n is the number of Wi-Fi signal pairs; if the MAC address of one Wi-Fi signal in fingerprint_; or in another fingerprint or _; does not exist, then the Wi-Fi signal and 0 form a Wi-Fi signal pair, and its _M value is 0;

7. A positioning device, the positioning device includes:

The positioning request receiving module is configured to receive a positioning request sent by the terminal to be located, wherein the positioning request includes the received signal strength indication RSSI value and the medium access control MAC address value of the wireless access node AP around the terminal to be located;

The fingerprint list search module is configured to search in a pre-established fingerprint database for a fingerprint list with the same MAC address value sent by the terminal to be located;

The fingerprint selection module is configured to calculate the fingerprint similarity between the fingerprints in the fingerprint list and the fingerprints sent by the terminal to be located, and select K fingerprints in order from high to low similarity; where K is a positive integer;

The positioning module is configured to generate a plurality of circumscribed circles based on the position coordinates of the K fingerprints saved in the fingerprint database, and determine the center coordinates of the minimum circumscribed circle, where the center coordinates of the minimum circumscribed circle are the terminal to be located. s position.

8. The positioning device according to claim 7, wherein the device further includes a fingerprint database establishment module configured as:

Receive the RSSI values, MAC address values, and the longitude and latitude values of the current location obtained by the user terminal of each wireless AP around it;

9. The positioning device according to claim 8, wherein: the fingerprint database establishing module, ¾JJ:

Calculate the fingerprint similarity between the fingerprint sent by the user terminal and the fingerprint saved in the fingerprint database;

Determine whether the fingerprint similarity of fingerprint ;, / is greater than the preset threshold. If so, merge the two fingerprints ;, / into one fingerprint and save it; if not, save the two fingerprints ;, f

10. The positioning device according to claim 9, wherein the fingerprint database establishment module is further configured to:

Calculate the fingerprint similarity of two fingerprints, ₇ , by the following formula:

SIM(f _{i ]} ) = (∑ __ _l W _m )ln;

Among them, is the similarity of the m-th Wi-Fi signal pair, and the Wi-Fi signal pair refers to two fingerprints_;, two Wi-Fi signals with the same MAC address in , n is the number of Wi-Fi signal pairs ; If the MAC address of one Wi-Fi signal in the fingerprint _; or does not exist in the other fingerprint or _, then the Wi-Fi signal and 0 form a Wi-Fi signal pair, and its _M value is 0;

11. The positioning device according to claim 9 or 10, wherein the fingerprint database establishment module is further configured to:

The two fingerprints L, / are combined into one fingerprint and saved by the following formula:

/{(rs^ mac _i )...(rs _n , mac _n ), Ion, lai]

={( ¹ 2 ¹ , +lon ^J )/2, (laf +lat ^J )/2}

Among them (r, ma _Cl )...(rs _n ^l , mac _n lori, tot' is the RSSI value, MAC address value of fingerprint_; and the longitude value and latitude value of the current location; (rs(, ma _Cl ). ..(rs _n , mac _n lon ^] , is the RSSI of fingerprint/. value, MAC address value, and longitude and latitude values of the current location.

12. The positioning device according to claim 7, wherein the fingerprint selection module is further configured to:

The fingerprint similarity between the fingerprints in the fingerprint list and the fingerprints sent by the terminal to be located is calculated by the following formula:

SIM(f _{i ]} ) = (∑ __ _l W _m )ln ;

13. A terminal, including:

The sending unit is configured to send a positioning request to the positioning device, wherein the positioning request includes the received signal strength indication RSSI value and the medium access control MAC address value of the wireless access node AP around the terminal to be located;

The receiving unit is configured to receive the position information fed back by the positioning device and display it.

14. The terminal according to claim 13, wherein the sending unit is further configured to: send to the positioning device the RSSI value and MAC address value of each wireless AP around it, as well as the longitude value and latitude value of its current location.

15. A computer storage medium in which computer-executable instructions are stored, and the computer-executable instructions are used to execute the method described in any one of claims 1 to 6.