WO2015117477A1

WO2015117477A1 - Indoor positioning method and device, and computer storage medium

Info

Publication number: WO2015117477A1
Application number: PCT/CN2014/092667
Authority: WO
Inventors: 王�琦
Original assignee: 中兴通讯股份有限公司
Priority date: 2014-08-25
Filing date: 2014-12-01
Publication date: 2015-08-13
Also published as: CN105467358A

Abstract

An indoor positioning method and device, and a computer storage medium. The method comprises: distributing multiple beacon nodes having known coordinates (S102); on the basis of indoor RSSI distance measurement tests, establishing conversion relations between RSSI values and distances (S104); transmitting the coordinate data of one or multiple beacon nodes to an unknown node (S104); establishing the coordinate of the unknown node according to the RSSI values of the beacon nodes measured by the unknown node, the received coordinate data, and the conversion relations (S106).

Description

Indoor positioning method, device and computer storage medium

Technical field

The present invention relates to the field of wireless communication positioning technologies, and in particular, to an indoor positioning method, apparatus, and computer storage medium.

Background technique

With the rapid development of modern communication, network, Global Position System (GPS), pervasive computing, distributed information processing and other technologies, location-aware computing and location-based services (LBS) are in practical applications. It seems to be more and more important. The practicality and necessity of precise positioning technology in many indoor scenes has become increasingly prominent.

GPS is currently the most widely used and successful positioning technology. The basic principle is to use the instantaneous position of the satellite moving at high speed as the known raw data, and then calculate the distance from the receiver to each satellite according to the time when the microwave signal arrives at the receiver. Finally, the method of determining the point to be measured by using the spatial distance resection s position. Since microwaves are easily absorbed by dense forests, buildings, metal coverings, etc., GPS is only suitable for outdoor use. In indoor situations, GPS is not suitable due to the complicated channel environment, strong attenuation of microwave signals, and large measurement error.

In the prior art indoor positioning, a regional positioning method is generally adopted. Based on Radio Frequency Identification (RFID) technology, some readers with known coordinates are arranged indoors as beacon nodes. The wireless signal of the reader can cover a certain range. The unknown node is passive with its own ID information. The electronic tag, when the unknown node moves into the coverage of a certain card reader signal, the beacon card reader recognizes the ID information of the unknown node, and reports the coordinates of the unknown node to the upper computer monitoring system with its own coordinates. Such positioning accuracy is low, and can only be located in one area, and cannot be accurate to specific coordinates. To obtain high positioning accuracy, a large number of beacon nodes must be set, thereby increasing the system cost, and the unknown node itself is passive. Does not have data processing functions, The node itself cannot know the general location in the room.

In view of the low accuracy of the indoor positioning method in the related art, an effective solution has not been proposed yet.

Summary of the invention

In order to solve the existing technical problems, embodiments of the present invention provide an indoor positioning method, device, and computer storage medium.

According to an aspect of the embodiments of the present invention, an embodiment of the present invention provides an indoor positioning method, including: arranging a plurality of beacon nodes with known coordinates; and measuring a received signal strength (RSSI) based on indoors. From the experiment, establishing a conversion relationship between the RSSI value and the distance; transmitting coordinate data of one or more beacon nodes to the unknown node; according to the RSSI value of each beacon node detected by the unknown node, the received coordinate data, And the conversion relationship, determining the coordinates of the unknown node.

In the above solution, the determining the relationship between the RSSI value and the distance based on the indoor RSSI ranging experiment includes: setting a plurality of measurement points within a specified range of each beacon node; and receiving the beacons of each measurement point The average value of the RSSI value of the data transmitted by the node is determined as the RSSI value of the corresponding beacon node; the RSSI value and the distance are established based on the RSSI value received at each measurement point and the distance from each measurement point to the corresponding beacon node. Conversion relationship.

In the above solution, the conversion relationship between the RSSI value and the distance is expressed by the following formula: [p(d)] _dBm = A-10nlog(d); wherein p(d) represents the signal strength, d represents the distance, A and n is a constant.

In the above solution, determining the coordinates of the unknown node according to the RSSI value of each beacon node detected by the unknown node, the received coordinate data, and the conversion relationship, including: according to the conversion relationship, the unknown The RSSI value of each beacon node detected by the node is converted into the distance between the unknown node and each beacon node; based on the maximum likelihood positioning algorithm, according to the distance between the unknown node and each beacon node, and each beacon node Coordinate data, calculate the The coordinates of the unknown node.

In the above solution, after determining the coordinates of the unknown node, the method further includes: displaying the coordinates of the unknown node in an electronic map form.

According to another aspect of the embodiments of the present invention, an embodiment of the present invention further provides an indoor positioning apparatus, where the apparatus includes: a relationship establishing module configured to arrange a plurality of beacon nodes with known coordinates; and based on the indoor RSSI Ranging experiment, establishing a conversion relationship between RSSI value and distance; a data sending module configured to send coordinate data of one or more beacon nodes to an unknown node; and a position determining module configured to detect each letter according to the unknown node The RSSI value of the target node, the received coordinate data, and the conversion relationship determine the coordinates of the unknown node.

In the above solution, the relationship establishing module includes: a signal strength determining unit configured to set a plurality of measurement points within a specified range of each beacon node; and transmit data of the beacon node received by each measurement point The average value of the RSSI value is determined as the RSSI value of the corresponding beacon node; the relationship establishing unit is configured to establish an RSSI value based on the RSSI value received at each measurement point and the distance from each measurement point to the corresponding beacon node. The conversion relationship of distance.

In the above solution, the location determining module includes: a converting unit configured to convert, according to the conversion relationship, an RSSI value of each beacon node detected by an unknown node into a distance between the unknown node and each beacon node; The coordinate calculation unit is configured to calculate the coordinates of the unknown node based on the distance between the unknown node and each beacon node and the coordinate data of each beacon node based on the maximum likelihood positioning algorithm.

In the above solution, the apparatus further includes: a display module configured to display coordinates of the unknown node in an electronic map form.

According to still another aspect of the embodiments of the present invention, an embodiment of the present invention further provides a computer storage medium, where the computer storage medium includes a set of instructions, when executed, causing at least one processor to perform the indoor positioning described above. method.

The beneficial effects of the embodiments of the present invention are as follows:

The indoor method proposed by the embodiment of the invention has high positioning precision and can locate specific coordinates, and the corresponding relationship between the RSSI value and the distance in the positioning ranging is obtained by collecting experimental data in an indoor scene that needs to be located, and is more in line with the indoor scene. The actual situation is more accurate than using the theoretical model of wireless signal propagation. At the same time, the positioning process is completed in the unknown node. The unknown node has powerful data processing capability, and can display the indoor geographic information map in real time, and the positioning coordinates are corresponding to the map, and there is an intuitive graphical user interface.

The above description is only an overview of the technical solutions of the present invention, and the above-described and other objects, features and advantages of the present invention can be more clearly understood. Specific embodiments of the invention are set forth below.

DRAWINGS

In the drawings, which are not necessarily to scale, the Like reference numerals with different letter suffixes may indicate different examples of similar components. The drawings generally illustrate the various embodiments discussed herein by way of example and not limitation.

1 is a flow chart of an indoor positioning method according to an embodiment of the present invention;

2 is a schematic diagram showing the composition of a beacon node according to an embodiment of the present invention;

3 is a schematic diagram showing the composition of an unknown node according to an embodiment of the present invention;

4 is a detailed flowchart of an indoor positioning method according to an embodiment of the present invention;

FIG. 5 is a block diagram showing the structure of an indoor positioning device according to an embodiment of the present invention.

detailed description

In order to solve the problem of the low accuracy of the indoor positioning method in the prior art, the embodiment of the present invention provides an indoor positioning method and device. The embodiments of the present invention are further described in detail below with reference to the accompanying 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.

This embodiment provides an indoor positioning method. FIG. 1 is a flowchart of an indoor positioning method according to an embodiment of the present invention. As shown in FIG. 1, the method includes the following steps (step S102 - step S106):

Step S102, arranging a plurality of beacon nodes with known coordinates; establishing a conversion relationship between the RSSI value and the distance based on the indoor RSSI ranging experiment;

Step S104, sending coordinate data of one or more beacon nodes to an unknown node;

Step S106: Determine coordinates of the unknown node according to the RSSI value of each beacon node detected by the unknown node, the received coordinate data, and the above conversion relationship.

The indoor method proposed in this embodiment has high positioning accuracy, and can locate specific coordinates, and the corresponding relationship between the RSSI value and the distance in the positioning ranging is obtained by collecting experimental data in an indoor scene that needs to be located, and is more in line with the indoor scene. The actual situation is more accurate than using the theoretical model of wireless signal propagation. At the same time, the positioning process is completed in the unknown node. The unknown node has powerful data processing capability, and can display the indoor geographic information map in real time, and the positioning coordinates are corresponding to the map, and there is an intuitive graphical user interface.

In this embodiment, before the plurality of beacon nodes whose coordinates are known are arranged, the two-dimensional geographic information coordinate system may be established in the indoor environment to be located. According to the specific range of the indoor environment to be located and the expected positioning accuracy, the position of the origin of the coordinate system and the coordinate precision of the x and y directions are set.

In step S102, based on the indoor RSSI ranging experiment, establishing a conversion relationship between the RSSI value and the distance may be implemented by: setting a plurality of measurement points within a specified range of each beacon node; receiving each measurement point The average value of the RSSI value of the data transmitted by the beacon node is determined as the RSSI value of the beacon node; based on the RSSI value received at each measurement point, and the distance from each measurement point to the corresponding beacon node, establishing The conversion relationship between RSSI values and distances. The position of multiple measurement points can be determined according to actual operation conditions. The distance from each measurement point to the corresponding beacon node can be calculated from the coordinates of the beacon node and the measurement point. Through the foregoing implementation manner, the accuracy of the RSSI value can be improved, and the subsequent positioning of the unknown node is proposed. For the foundation.

In step S106, determining the coordinates of the unknown node according to the RSSI value of each beacon node detected by the unknown node, the received coordinate data, and the conversion relationship may be implemented by the following implementation manner: according to the conversion relationship, the unknown The RSSI value of each beacon node detected by the node is converted into the distance between the unknown node and each beacon node; based on the maximum likelihood localization algorithm, according to the distance between the unknown node and each beacon node, and the distance of each beacon node The coordinate data calculates the coordinates of the unknown node. With this embodiment, the positioning accuracy of the unknown node is improved. After that, the coordinates of the unknown node can be displayed as an electronic map. In an embodiment, it may also be displayed in the form of text information or the like. The specific display mode is determined according to the actual operation.

The beacon node and the unknown node in this embodiment are respectively explained below. 2 is a schematic diagram of the composition of a beacon node according to an embodiment of the present invention. As shown in FIG. 2, the main function of the beacon node is to transmit wireless data, and the data storage amount and processing requirements are not high, so the processor can use 8 bits 51. The MCU 21, the data storage can use the processor on-chip storage resources to meet the demand. The peripheral circuit has a clock 22, a power source 23, a switch 24, and the like. For the indoor environment, because the location area is limited, using the WIFI module 25 to wirelessly transmit and receive data can cover the location area.

FIG. 3 is a schematic diagram of the composition of an unknown node according to an embodiment of the present invention. As shown in FIG. 3, the main function of the unknown node is to receive data sent by the beacon node as a receiver, and process the data to realize positioning of itself. Specifically, the data sent by the beacon node is stored, the data is processed by the positioning algorithm to calculate its own coordinates, the positioning result is displayed in the form of a map, and the operation of zooming in and out of the map can be realized. Therefore, the function is complicated, the processor can select a 32-bit ARM processor 31, and the peripheral circuit can have a memory 32, a touch screen 33, an LCD display 34, a clock 35, a power supply 36, a switch 37, and a WIFI module 38.

The indoor positioning method of the present invention will be described in detail below through specific embodiments and the accompanying drawings.

4 is a detailed flowchart of an indoor positioning method according to an embodiment of the present invention, as shown in FIG. The flow includes the following steps (step S402 - step S412):

Step S402, establishing a two-dimensional geographic information coordinate system of the indoor environment to be located;

Here, the position of the coordinate origin and the coordinate precision of the x and y directions are set according to the specific range of the indoor environment to be located and the expected positioning accuracy.

In the embodiment of the invention, the positioning accuracy is set to be 0.1 m.

Step S404, performing an indoor RSSI ranging experiment in the indoor environment to be located, and fitting the collected experimental data to obtain a relationship formula between the RSSI value and the distance d;

The specific method can be:

Select a fixed location indoors, place the beacon node module transmitter, and set the output power of the transmitter. After the transmitter is fixed, the unknown node is set as the receiver. It is assumed that 100 measurement points are set within a range of 20 m from the transmitter at intervals of 20 cm, that is, 0.2 m, 0.4 m, ... 20 m from the transmitter. The receiver is programmed to set an RSSI value buffer to store the RSSI value of the received data packet. After receiving 100 data packets at each test point, average the 100 RSSI values, and then average the RSSI. The value is the signal strength received by the beacon node at that location.

Finally, the correspondence between the RSSI value and the distance d is recorded, and 100 sets of measurement data (RSSI _i , d _i ), i=1, 2, 3, . . . 100 are obtained, where RSSI _i represents the RSSI measurement value when the distance is d _i . According to the wireless signal transmission theory, the theoretical formula of the signal strength p(d) received by the receiving end when the transmitter is d is the RSSI in dBm is:

[p(d)] _dBm =A-10nlog(d) (1)

Among them, the parameters A and n need to be determined, and the measured parameters of the 100 sets of data are used to obtain the parameters A and n in the formula. This gives a conversion formula for the RSSI value and the distance d. The unknown node can calculate the distance from the beacon node from the received RSSI value.

Step S406, in the indoor environment to be located, a beacon node whose coordinates are known is arranged (in the actual operation, the operation may also be performed simultaneously in step S402), and the beacon node is set. The working mode is to send its own ID and coordinate information;

Specifically, a certain number of beacon nodes are placed in a location where a known coordinate is selected indoors, and the beacon node layout should cover the entire indoor to-be-positioned area, and the layout density should be reasonably selected. The more beacon layout, the higher the positioning accuracy. The hardware cost is also increased, and the positioning accuracy and cost should be comprehensively considered. In the embodiment of the present invention, the distance between the beacons is 5 m as an example.

The specific steps of the beacon node work include:

(1) Module initialization, set your own ID and coordinates.

(2) Set the communication mode to the transmitter.

(3) Set the WIFI module output power.

(4) Send data.

Step S408, the unknown node receives and stores the data sent by each beacon node, and detects the signal strength of each beacon node, and converts it into an RSSI value, and then converts the RSSI value into a distance d;

The specific steps include:

(1) Module initialization.

(2) Set the communication mode to the receiver.

(3) Receive the data packets sent by each beacon node and store them in the buffer area.

(4) Processing the data packet received in the buffer area, and extracting information such as the ID and coordinates of the beacon node. The WIFI wireless data packet has a corresponding field indicating the signal strength when the data packet is received, and extracting the field data from the received data packet is the RSSI value.

If the detected RSSI value has reached the RSSI value from the 10 beacon nodes, the reception of the data packet is stopped. The relationship fitted by the ranging experiment is used to convert the RSSI value into the distance d, thus obtaining the distance between the unknown node and 10 different beacon nodes. If not, the unknown node continues to receive the packet acquisition RSSI value.

Step S410, the unknown node uses the maximum likelihood localization algorithm to calculate the coordinates of the preset number of beacon nodes and the distance to the beacon nodes.

This step uses the existing positioning algorithm, and the calculation of the coordinates of the unknown nodes is directly derived from the formula of the algorithm.

In step S412, the unknown node displays its real-time location on the map.

Here, the unknown node has an LCD display system, and the indoor environment geographic information electronic map is implemented by software on the unknown node, the coordinate system of the map is consistent with the two-dimensional geographic information coordinate system established in step S402, and the unknown node calculates its own coordinates. After that, the positioning result is displayed and updated on the electronic map in real time by software control.

In this embodiment, the function of the beacon node is to transmit its own coordinates and ID data as a transmitter. The function of the unknown node is to receive the data sent by the beacon node as a receiver and process the data to achieve its own positioning. The indoor positioning method introduced in the embodiment solves the problem that the accuracy of the indoor positioning method in the related art is low.

Corresponding to the indoor positioning method introduced in the above embodiment, the present embodiment provides an indoor positioning device, which is used to implement the above embodiment. FIG. 5 is a structural block diagram of an indoor positioning apparatus according to an embodiment of the present invention. As shown in FIG. 5, the apparatus includes a relationship establishing module 10, a data sending module 20, and a position determining module 30. The structure is described in detail below.

The relationship establishing module 10 is configured to arrange a plurality of beacon nodes with known coordinates; and establish a conversion relationship between the RSSI value and the distance based on the indoor received signal strength RSSI ranging experiment;

The data sending module 20 is connected to the relationship establishing module 10, and configured to send coordinate data of one or more beacon nodes to the unknown node;

The location determining module 30 is coupled to the data sending module 20, and configured to determine coordinates of the unknown node according to the RSSI value of each beacon node detected by the unknown node, the received coordinate data, and the conversion relationship.

According to the indoor positioning device provided in this embodiment, indoor positioning is performed, the positioning accuracy is high, and specific coordinates can be located, and the corresponding relationship between the RSSI value and the distance in the positioning ranging is obtained by collecting experimental data in an indoor scene that needs to be positioned. Out, more in line with the actual situation of the indoor scene, More accurate than using a wireless signal propagation theory model. At the same time, the positioning process is completed in the unknown node. The unknown node has powerful data processing capability, and can display the indoor geographic information map in real time, and the positioning coordinates are corresponding to the map, and there is an intuitive graphical user interface.

In order to improve the positioning accuracy, the present embodiment provides a specific implementation manner, and the specific determination process of the conversion relationship between the RSSI value and the distance is described in detail, that is, the relationship establishing module 10 may include:

a signal strength determining unit configured to set a plurality of measurement points within a specified range of each beacon node; determining an average value of RSSI values of data transmitted by the beacon node received by each measurement point as the beacon node RSSI value;

The relationship establishing unit is configured to establish a conversion relationship between the RSSI value and the distance based on the RSSI value received at each measurement point and the distance from each measurement point to the corresponding beacon node.

In order to improve the positioning accuracy, the embodiment provides a specific implementation manner, and details the coordinate calculation process of the unknown node, that is, the location determining module 30 may include:

a converting unit, configured to convert, according to the conversion relationship, an RSSI value of each beacon node detected by an unknown node into a distance between the unknown node and each beacon node;

The coordinate calculation unit is configured to calculate the coordinates of the unknown node based on the distance between the unknown node and each beacon node and the coordinate data of each beacon node based on the maximum likelihood positioning algorithm.

In order to improve the user experience, the embodiment further provides an implementation manner, that is, the foregoing apparatus further includes: a display module configured to display coordinates of the unknown node in an electronic map form.

In practical applications, the relationship establishing module 10, the relationship establishing unit, and the coordinate calculating unit may be a central processing unit (CPU), a microprocessor (MCU, a digital control unit), a digital signal processor in an indoor positioning device. (DSP, Digital Signal Processor) or a programmable logic array (FPGA); the data transmitting module 30 can be implemented by a transmitter in an indoor positioning device, the position determining module 30, the signal strength The determining unit and the converting unit may be in the indoor positioning device The CPU, MCU, DSP or FPGA implementation is implemented in conjunction with the receiver.

With the technical solution described in the embodiment of the present invention, an indoor positioning method with high positioning accuracy is realized, and the specific process is as follows:

(1) establishing a two-dimensional geographic information coordinate system of the indoor environment to be located;

(2) Performing a range-based experiment based on the RSSI value in the indoor environment to be located, and fitting the experimental data to obtain a relationship formula between the RSSI value and the distance d;

(3) arranging beacon nodes with known coordinates in the room, and setting the working mode of the beacon node to transmit its own ID and coordinate information;

(4) The unknown node to be located receives and stores the data sent by each beacon node, and detects the RSSI value of each beacon node, and converts the RSSI value into a distance;

(5) The unknown node uses the maximum likelihood localization algorithm to calculate its own coordinates from the preset number of beacon coordinates collected and the distance to these beacon nodes;

(6) The unknown node displays its real-time location on the map.

Based on the above process, better indoor positioning can be achieved, which is more accurate than using the wireless signal propagation theory model. At the same time, the positioning coordinates are mapped on the map, and an intuitive graphical user interface is provided to improve the user experience.

Those skilled in the art will appreciate that embodiments of the present invention can be provided as a method, system, or computer program product. Accordingly, the present invention can take the form of a hardware embodiment, a software embodiment, or a combination of software and hardware. Moreover, the invention can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage and optical storage, etc.) including computer usable program code.

The present invention has been described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (system), and computer program products according to embodiments of the invention. It will be understood that each flow and/or block of the flowchart illustrations and/or FIG. These computer program instructions can be provided to a general purpose computer, a special purpose computer, An processor of an embedded processor or other programmable data processing device to generate a machine such that instructions executed by a processor of a computer or other programmable data processing device are generated for implementation in a flow or a flow of flowcharts and/or Or a block diagram of a device in a box or a function specified in a plurality of boxes.

The computer program instructions can also be stored in a computer readable memory that can direct a computer or other programmable data processing device to operate in a particular manner, such that the instructions stored in the computer readable memory produce an article of manufacture comprising the instruction device. The apparatus implements the functions specified in one or more blocks of a flow or a flow and/or block diagram of the flowchart.

These computer program instructions can also be loaded onto a computer or other programmable data processing device such that a series of operational steps are performed on a computer or other programmable device to produce computer-implemented processing for execution on a computer or other programmable device. The instructions provide steps for implementing the functions specified in one or more of the flow or in a block or blocks of a flow diagram.

Based on this, an embodiment of the present invention further provides a computer storage medium, the computer storage medium comprising a set of instructions, when executed, causing at least one processor to perform the indoor positioning method.

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.

Claims

An indoor positioning method, the method comprising:

Arranging a plurality of beacon nodes with known coordinates; establishing a conversion relationship between the RSSI value and the distance based on the indoor received signal strength RSSI ranging experiment;

Sending coordinate data of one or more beacon nodes to an unknown node;

The coordinates of the unknown node are determined according to the RSSI value of each beacon node detected by the unknown node, the received coordinate data, and the conversion relationship.
The method of claim 1 wherein said establishing an RSSI value to a distance based on an indoor RSSI ranging experiment comprises:

Setting a plurality of measurement points within a specified range of each beacon node;

Determining an average value of RSSI values of data transmitted by the beacon node received by each measurement point as an RSSI value corresponding to the beacon node;

The conversion relationship between the RSSI value and the distance is established based on the RSSI value received at each measurement point and the distance from each measurement point to the corresponding beacon node.
The method according to claim 1 or 2, wherein the conversion relationship between the RSSI value and the distance is expressed by the following formula:

[p(d)] dBm = A-10n log(d); where p(d) represents the signal strength, d represents the distance, and A and n are constants.
The method of claim 1, wherein the determining the coordinates of the unknown node based on the RSSI value of each beacon node detected by the unknown node, the received coordinate data, and the conversion relationship comprises:

And converting, according to the conversion relationship, an RSSI value of each beacon node detected by the unknown node to a distance between the unknown node and each beacon node;

Based on the maximum likelihood localization algorithm, the coordinates of the unknown node are calculated according to the distance between the unknown node and each beacon node and the coordinate data of each beacon node.
The method of claim 1, wherein after determining the coordinates of the unknown node, the method further comprises:

The coordinates of the unknown node are displayed as an electronic map.
An indoor positioning device, the device comprising:

a relationship establishing module configured to arrange a plurality of beacon nodes with known coordinates; and based on an indoor received signal strength RSSI ranging experiment, establishing a conversion relationship between the RSSI value and the distance;

a data sending module configured to send coordinate data of one or more beacon nodes to an unknown node;

The location determining module is configured to determine coordinates of the unknown node according to the RSSI value of each beacon node detected by the unknown node, the received coordinate data, and the conversion relationship.
The apparatus of claim 6, wherein the relationship establishing module comprises:

a signal strength determining unit configured to set a plurality of measurement points within a specified range of each beacon node; and determine an average value of RSSI values of data transmitted by the beacon node received by each measurement point as a corresponding beacon The RSSI value of the node;

The relationship establishing unit is configured to establish a conversion relationship between the RSSI value and the distance based on the RSSI value received at each measurement point and the distance from each measurement point to the corresponding beacon node.
The apparatus of claim 6 wherein said location determining module comprises:

a converting unit, configured to convert, according to the conversion relationship, an RSSI value of each beacon node detected by an unknown node into a distance between the unknown node and each beacon node;

The coordinate calculation unit is configured to calculate the coordinates of the unknown node based on the distance between the unknown node and each beacon node and the coordinate data of each beacon node based on the maximum likelihood positioning algorithm.
The device of claim 6 wherein said device further comprises:

A display module configured to display coordinates of unknown nodes in an electronic map.
A computer storage medium, the computer storage medium comprising a set of instructions When the instructions are executed, at least one processor is caused to perform the indoor positioning method according to any one of claims 1 to 5.