CN112986898B - Decentralized beacon positioning system - Google Patents
Decentralized beacon positioning system Download PDFInfo
- Publication number
- CN112986898B CN112986898B CN202110171457.9A CN202110171457A CN112986898B CN 112986898 B CN112986898 B CN 112986898B CN 202110171457 A CN202110171457 A CN 202110171457A CN 112986898 B CN112986898 B CN 112986898B
- Authority
- CN
- China
- Prior art keywords
- beacon
- fixed
- packet
- mobile
- ranging
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S1/00—Beacons or beacon systems transmitting signals having a characteristic or characteristics capable of being detected by non-directional receivers and defining directions, positions, or position lines fixed relatively to the beacon transmitters; Receivers co-operating therewith
Abstract
The invention provides a decentralized beacon positioning system, which comprises: a plurality of fixed beacons and mobile beacons, wherein the fixed beacons are in a calibration mode or a base station mode, and when in the calibration mode, a distance information table is established and the distance information between the fixed beacons and the surrounding fixed beacons is stored; providing ranging information and a range information table for the mobile beacon when in the base station mode; the mobile beacon is in a calibration mode or a positioning mode, and when the mobile beacon is in the calibration mode, a map information table is established and original point information of a coordinate system set by the mobile beacon and space coordinates of a fixed beacon communicated with the mobile beacon in the coordinate system are stored; when the mobile station is in the base station mode, the mobile station uses the ranging information, the distance information table and the map information table of the fixed beacon communicated with the mobile station to position the mobile station and the fixed beacon communicated with the mobile station, updates the map information table by using the positioning result of the fixed beacon, and outputs the positioning information of the mobile station.
Description
Technical Field
The invention relates to the field of beacon positioning, in particular to a decentralized beacon positioning system.
Background
The beacon positioning system is a system for obtaining three-dimensional or two-dimensional space coordinates of beacons through communication between the beacons so as to be used by other equipment. The beacon positioning system comprises two parts of a fixed beacon and a mobile beacon. Fixed beacons are mounted on walls, ceilings, or other mounting planes in the environment for providing positioning reference information. The mobile beacon is installed on the user equipment, receives the fixed tag signal, calculates the current space coordinate and provides the current space coordinate for the user equipment to use. The process of the beacon positioning system can be divided into two parts of map building and positioning; the mapping refers to establishing a coordinate system, and obtaining the space coordinates of all the fixed beacons under the coordinate system in a measuring or calibrating mode; the positioning means that the mobile beacon calculates the real-time space coordinate of the mobile beacon through communication with the fixed beacon; the positioning system can enter the positioning link to provide positioning information only after completing the map building link.
The existing beacon positioning system needs centralized nodes as the basis of system initialization, information communication, node coordination and data storage; the node can be a special device or a set of software deployed on a device with computing function; for positioning, the most important function of the centralized node is to specify a spatial coordinate system, establish and store spatial coordinates of all fixed beacons in the network, and generate a global positioning network map. The mobile beacon calculates self-positioning information by taking the global positioning network as a reference. Given that providing accurate positioning information would be an important infrastructure to support smart city construction, a challenge facing beacon positioning systems would be the intercity range of very large scale positioning networks.
The existing positioning system comprising the centralized node faces the following problems:
1. the stability is poor, once a central node has a problem, the system is paralyzed and cannot be normally used;
2. the expansibility is poor, any change of the system needs to be changed through a central node, and the larger the network scale is, the higher the change cost is;
3. the deployment is complex, a professional is required to initialize the whole positioning network, and the initialized quality directly determines the positioning accuracy;
4. the coverage area is limited, and the signal coverage range of the central node determines the use range of the system;
5. the throughput is small and the throughput of the central node limits the number of users in use in the coverage area.
Disclosure of Invention
The present invention is directed to overcome the above technical drawbacks, and provides a decentralized beacon positioning system, including: a plurality of fixed beacons, as well as mobile beacons,
the fixed beacon is in a calibration mode or a base station mode, and when the fixed beacon is in the calibration mode, a distance information table is established and the distance information between the fixed beacon and the surrounding fixed beacons is stored; providing ranging information and a range information table for the mobile beacon when in the base station mode;
the mobile beacon is in a calibration mode or a positioning mode, and when the mobile beacon is in the calibration mode, a map information table is established and original point information of a coordinate system set by the mobile beacon and space coordinates of a fixed beacon communicated with the mobile beacon in the coordinate system are stored; when the mobile station is in the base station mode, the mobile station uses the ranging information, the distance information table and the map information table of the fixed beacon communicated with the mobile station to position the mobile station and the fixed beacon communicated with the mobile station, updates the map information table by using the positioning result of the fixed beacon, and outputs the positioning information of the mobile station.
As an improvement of the above system, the fixed beacon is provided with a first channel and a second channel,
the first channel is used for sending and monitoring a state information packet; the status information packet includes: a heartbeat packet, a synchronization packet, a ranging result packet, a trigger packet, a repeat packet and a confirmation packet;
the second channel is used for sending and monitoring a ranging packet in a calibration mode; in the base station mode, ranging packets, which are a series of encoded time sequences used to calculate the time of flight of the signal, are monitored.
As an improvement of the above system, the fixed beacon is provided with a monitoring module, configured to send a heartbeat packet including a fixed beacon ID number through a first channel; the fixed beacon is also used for monitoring heartbeat packets sent by other fixed beacons, and when the heartbeat packets of other beacons are received, whether the heartbeat packet is the first received heartbeat packet of the beacon is judged; if yes, entering a calibration mode; otherwise, continuously monitoring heartbeat packets sent by other fixed beacons.
As an improvement of the above system, a current fixed beacon is denoted as a fixed beacon a, and a fixed beacon receiving a first heartbeat packet is denoted as a fixed beacon B; when the fixed beacon A is in the calibration mode, the fixed base station A executes the following steps:
the fixed beacon A periodically sends a synchronization packet to the fixed beacon B through a first channel, and simultaneously sends a ranging packet to the fixed beacon B through a second channel;
after receiving the synchronization packet and the ranging packet, the fixed beacon B starts to calculate the distance between the fixed beacon B and the fixed beacon A;
after the calculation is successful, the fixed beacon B sends the ranging result to the fixed beacon A through a first channel of the fixed beacon B;
after receiving the ranging result of the fixed beacon B, the fixed beacon A sends a trigger packet through a first channel of the fixed beacon A;
after receiving the trigger packet, the fixed beacon B periodically transmits a synchronization packet to the fixed beacon A through a first channel of the fixed beacon B, and simultaneously transmits a ranging packet to the fixed beacon A through a second channel of the fixed beacon B;
after receiving the synchronization packet and the ranging packet, the fixed beacon A calculates the distance between the fixed beacon A and the fixed beacon B as a calculated ranging result;
the fixed beacon A judges whether the difference between the ranging result sent by the fixed beacon B and the calculated ranging result is smaller than a threshold value; if the judgment result is positive, sending a confirmation packet to the fixed beacon B, storing the calculated ranging result into a distance information table, and exiting the calibration mode; otherwise, sending a repeated packet and re-entering the calibration mode.
As an improvement of the above system, when the fixed beacon is in the base station mode, the fixed base station performs the following steps:
monitoring a synchronous packet sent by a mobile beacon in real time;
after receiving the synchronous packet of the mobile beacon, calculating the distance between the mobile beacon and the synchronous packet of the mobile beacon as a ranging result;
and sending the ranging result and the locally stored distance information table to the mobile beacon.
As an improvement of the above system, the mobile beacon is provided with a first channel and a second channel;
the first channel is used for sending a synchronization packet containing coding information and receiving an information packet containing a ranging result sent back by the fixed beacon; the coded information comprises the ID number and the time sequence number of the mobile beacon;
the second channel is used for transmitting a ranging packet containing codes; a ranging packet is a series of encoded ranging signals that contain a beacon ID.
As an improvement of the above system, when the mobile beacon is in the calibration mode, the mobile beacon performs the following steps:
step S1) sending a synchronization packet through the first channel, and sending a ranging packet through the second channel;
step S2), monitoring the ranging result packet of the fixed beacon through the first channel, and when the number of the received ranging results meets the positioning requirement: the number of three-dimensional positioning is more than 3, and the number of two-dimensional positioning is more than 2; proceeding to step S3);
step S3) configuring a coordinate origin and a coordinate system; calculating space coordinates of the mobile beacons and the fixed beacons under the coordinate system by adopting a triangular synchronous positioning algorithm according to ranging information sent by the fixed beacons and distance information among the fixed beacons in a distance information table;
step S4), calculating the coordinate position of the mobile beacon through the ranging information for a plurality of times, and checking whether the positioning precision meets the requirement; if yes, go to step S6), otherwise, go to step S5);
step S5) adds a fixed beacon around the mobile beacon or changes the position, and proceeds to step S2);
step S6) writes the coordinate position of the mobile beacon into the map information table as the origin of the coordinate system, and writes the space coordinate of the fixed beacon communicating with the mobile beacon into the map information table in the coordinate system, and shifts to the positioning mode.
As an improvement of the above system, when the mobile beacon is in the positioning mode, the mobile beacon performs the following steps:
sending a synchronization packet through a first channel, and simultaneously sending a ranging packet through a second channel;
receiving a ranging result returned by the fixed beacon, and loading a coordinate value of the fixed beacon from a map information table;
taking the coordinate values and the ranging results of the loaded fixed beacons as initial values, and simultaneously calculating the space coordinates of the mobile beacons and the surrounding fixed beacons by adopting a triangular synchronous positioning algorithm;
and rewriting the space coordinates of the surrounding fixed beacons into a map information table, and outputting the positioning information of the mobile beacons.
As an improvement of the above system, the coordinate values and ranging results of the loaded fixed beacons are used as initial values, and a triangular synchronous positioning algorithm is adopted to simultaneously calculate the spatial coordinates of the mobile beacons and the surrounding fixed beacons; the method specifically comprises the following steps:
and (3) listing a distance equation between beacons, and subtracting the distance equation with the ranging result to obtain an error term:
wherein (x)0,y0,z0) To move the position of the coordinate, (x)i,yi,zi) I is more than or equal to 1 and less than or equal to N, and N is the number of the fixed beacons for sending the ranging result to the mobile coordinate; (x)0,y0,z0) And (x)i,yi,zi) Is a parameter to be solved; ranging result d between fixed beacon and mobile beaconi0Ranging result d between fixed beaconsijIs a known parameter, wherein the range d between fixed beaconsijObtaining the distance information through a distance information table;
to fix the actual distance between the beacon and the mobile beacon,
is an error;
is the actual distance between the ith and jth fixed beacons,
is an error;
solving N +1 space positions (x) satisfying the minimum sum of squares f of all error terms by using a nonlinear optimization method0,y0,z0)、(x1,y1,z1)、…、(xN,yN,zN)：
The coordinate values of the fixed beacons recorded in the map information table can be used as the initial iteration values, and the fixed beacons not recorded in the map information table can randomly generate a group of coordinate values as the initial iteration values.
The space coordinate (x) of the surrounding fixed beacon is calculated1,y1,z1)、…、(xN,yN,zN) Updating the information in the map information table and outputting the positioning information (x) of the mobile beacon0,y0,z0)。
The invention has the advantages that:
1. the stability is strong, the system operation does not depend on a certain beacon, and the positioning information can be provided only by meeting the requirement that more than 3 beacons are visible at the same time;
2. the installation and deployment are simple and convenient, the fixed labels are directly communicated, the distance information between the fixed labels is stored, the system does not need to be initialized, and the origin of the positioning system is calibrated;
3. the positioning network is flexible, the beacons in the network can be increased and decreased at any time, and the change does not influence the operation of the existing beacons in the network;
4. the beacon resources are shared, the beacons do not belong to any positioning system, and all fixed beacons in the coverage area of the mobile beacons can be used.
Drawings
Fig. 1 is a schematic diagram illustrating two states of beacon configuration and beacon positioning of the beacon positioning system of the present invention;
FIG. 2 is a schematic diagram of two modes of a fixed beacon of the present invention;
FIG. 3 is a schematic view of the installation of the fixed beacon of the present invention;
FIG. 4 is a flow chart of initialization of a fixed beacon of the present invention;
FIG. 5 is a timing diagram illustrating a fixed beacon calibration mode according to the present invention;
FIG. 6 is a flow chart of the fixed beacon base station mode of the present invention;
FIG. 7 is a schematic diagram of two modes of mobile beacons according to the present invention;
FIG. 8 is a flow chart of initialization of a mobile beacon of the present invention;
FIG. 9 is a timing diagram illustrating a mobile beacon calibration mode according to the present invention;
FIG. 10 is a flow chart of the mobile beacon location mode of the present invention;
FIG. 11 is a schematic diagram of a triangulation synchronization positioning algorithm.
Detailed Description
The technical solution of the present invention will be described in detail below with reference to the accompanying drawings.
The technical scheme principle of the invention is as follows: replacing the global coordinate system concept with the local coordinate system concept, and not establishing a global coordinate system in the image establishing link; the fixed beacon stores distance information with surrounding beacons, and the distance information replaces space coordinate information to be used as a medium for exchanging with the mobile beacon; the mobile beacon calculates the space coordinates of the mobile beacon and the fixed beacon at the same time by means of a triangular synchronous positioning algorithm.
The beacon location system of the present invention can be divided into two categories of beacons: a fixed beacon and a mobile beacon; for convenience of description, the system can be divided into two states of beacon configuration and beacon positioning. These two states are self-cycling and independent, rather than being back-and-forth dependent.
The beacon configuration refers to the working state of a fixed beacon, and the main purpose is to measure the distance relation with the surrounding fixed beacons; when a fixed beacon is changed, such as operations of adding, replacing, reducing and the like, only the fixed beacon in the communication coverage area of the beacon is influenced, and other beacons are not influenced. Beacon positioning refers to the working state of a mobile beacon, and is mainly used for outputting the space coordinates of the mobile beacon and the information of a map for a user to use through communication with a fixed beacon. As shown in fig. 1.
There are two main modes of fixed beacons: a calibration mode and a base station mode, which communicate through two channels (channel 1 and channel 2); as shown in fig. 2.
And (3) calibration mode:
channel 1: sending and monitoring a state information packet;
and (3) a channel 2: sending and monitoring a ranging packet;
base station mode:
channel 1: sending and monitoring a state information packet;
and (3) a channel 2: monitoring a ranging packet;
the channel 1 needs to be normally opened, and a low-power-consumption communication mode can be adopted;
the channel 2 has large transmission power consumption, and a single receiving mode is adopted in the base station mode in order to prolong the service time;
the purpose of the state information packet is to coordinate the transceiving relation among the fixed tags, such as a heartbeat packet, a synchronization packet, a ranging result packet, a trigger packet, a repeat packet, an acknowledgement packet and the like;
a ranging packet is a series of encoded time series used to calculate the time of flight of a signal, such as a frequency modulated signal (FM), amplitude modulated signal (AM), code division multiple access signal (CDMA), etc.;
the fixed beacon needs to store a distance information table, and the table records the distance information with the surrounding fixed beacons;
TABLE 1 distance information Table
| Beacon | Distance between two adjacent plates |
| Fixed beacon 1 | |
| Fixed beacon 2 | |
| …… |
And (3) fixed beacon installation: for a three-dimensional positioning system, there are at least three and more other beacons around each beacon; for a two-dimensional positioning system, there are at least two and more other beacons around each beacon; direct visibility is ensured between beacons, and the middle part is not shielded; the inside of the convex polygon formed by the beacons belongs to a working area, and the provided positioning accuracy is high. As shown in fig. 3.
Fixed beacon initialization: after the fixed beacon is electrified, the fixed beacon enters an initialization state and waits for ID number allocation or ID number autonomous generation; starting to transmit a heartbeat packet containing a beacon ID number through a channel 1; and meanwhile, monitoring heartbeat packets sent by surrounding beacons. When receiving the heartbeat packets of other beacons, judging whether the heartbeat packet is received for the first time; if the first time of receiving, entering a calibration mode; otherwise, continuing to monitor the heartbeat packet; after exiting the calibration mode, judging whether the number of the confirmed distances between the labels and the surrounding labels meets the positioning requirement, namely the two-dimensional positioning is more than 2, and the three-dimensional positioning is more than 3; if yes, storing the information in a distance information table, and entering a base station mode; otherwise, the heartbeat packet is continuously monitored. As shown in fig. 4.
Fixed beacon calibration mode:
take 2 fixed beacons as an example, where beacon 2 newly joins the network; the beacon 2 finds the beacon 1 in the network through the heartbeat packet and enters a calibration mode; as shown in fig. 5.
Step 101) beacon 2 periodically sends synchronous packets through channel 1, and sends ranging packets through channel 2;
step 102), after receiving the synchronization packet and the ranging packet, the beacon 1 starts to calculate the distance to the beacon 2;
step 103), after the calculation is successful, the beacon 1 sends the ranging result to the beacon 2 through the channel 1;
step 104) after receiving the ranging result of the beacon 1, the beacon 2 sends a trigger packet;
step 105) after receiving the trigger packet, the beacon 1 starts to send a synchronization packet and a ranging packet;
step 106) after the beacon 2 receives the synchronization packet and the ranging packet, the distance between the beacon 2 and the beacon 1 is calculated;
step 107) determines whether the ranging result transmitted by the beacon 1 and the calculated ranging result match.
Step 108) if the measurement results are consistent, sending a confirmation packet and exiting the calibration mode; otherwise, sending a repeat packet and repeating the step 1);
step 109), after receiving the confirmation packet, the beacon 1 exits from the calibration mode; otherwise, go to step 102);
if heartbeat packets of a plurality of beacons are received at the same time, sequentially calibrating beacon distances;
fixed beacon base station mode:
after entering the base station mode, the beacon starts to provide service for the mobile beacon; as shown in fig. 6:
step 201) monitoring a synchronization packet sent by a mobile beacon in real time;
step 202), after receiving, starting to calculate the distance between the mobile beacon and the mobile beacon;
step 203), after the result is calculated, the ranging result and the stored distance information table are sent to the mobile beacon;
step 204) monitoring whether a newly added fixed tag exists; and if the newly added fixed tag exists, exiting the base station mode and entering a calibration mode.
Mobile beacon
The mobile beacon mainly has two modes (calibration and positioning) and communicates through two channels; as shown in fig. 7:
the channel 1 is used for sending a synchronization packet containing coding information and receiving an information packet containing a ranging result sent back by a fixed beacon; the coded information comprises beacon ID numbers and time sequence numbers for distinguishing;
channel 2 is used for transmitting a ranging packet containing codes; a ranging packet is a series of encoded ranging signals that contain a beacon ID. On one hand, the method is used for improving the distance measurement precision; on the other hand, for distinguishing from other mobile beacons;
the channel 1 adopts a low-power-consumption communication mode and needs to be normally opened; the channel 2 adopts a high-power communication mode, so that the distance measuring signal is ensured to be strong enough, and the positioning precision is improved;
a map information table is required to be stored in the mobile beacon, and the table comprises a coordinate system and origin information set by the mobile beacon and space coordinates of the fixed beacon under the coordinate system;
TABLE 2 map information Table
| Beacon | x | y | z |
| Origin point | |||
| Fixed beacon 1 | |||
| Fixed beacon 2 | |||
| …… |
Mobile beacon initialization: the purpose of the initialization stage of the mobile beacon is to determine whether the system needs to calibrate a coordinate system and an origin; after the beacon is electrified, whether the beacon is used for the first time is detected, namely whether a map information table exists in the beacon is judged; if not, directly entering a calibration mode; otherwise, inquiring whether to reset the coordinate system configuration; if not, directly entering a positioning mode; otherwise, entering a calibration mode; as shown in fig. 8.
Mobile beacon calibration mode: the purpose of the calibration mode is to calibrate the spatial coordinate system and the origin of the beacon, as shown in fig. 9, the calibration process is as follows:
step 301) sending a synchronization packet through a channel 1, and sending a ranging packet through a channel 2;
step 302) monitoring the ranging result packet of the fixed beacon through the channel 1, and waiting for the number of the received ranging results to meet the positioning requirement (the three-dimensional positioning is more than 3, and the two-dimensional positioning is more than 2);
step 303), when the number is satisfied, starting to configure a coordinate origin and a coordinate system, wherein the coordinate origin and the coordinate system can be specified by a user, and the position of the beacon can also be used as the origin;
step 304) calculating space coordinates of the mobile beacons and the fixed beacons under the coordinate system by adopting a triangular synchronous positioning algorithm according to ranging information sent by the fixed beacons and distance information among the fixed beacons;
step 305) calculating a coordinate position through multiple times of ranging information, and comparing whether a coordinate result is stable or not to check whether the positioning precision meets the requirement or not;
step 306), if the condition is not met, the problem can be solved by increasing the number of the fixed labels or replacing the positions, and the step 302) is carried out;
step 307) after the space coordinates of the mobile beacon are determined, recording a coordinate system and an origin point into a map information table, and enabling the beacon to enter a positioning mode;
as shown in fig. 10, mobile beacon positioning mode:
step 401) after entering the positioning mode, determining whether the coordinate system needs to be reset. If necessary, entering a calibration mode; otherwise, starting ranging;
step 402) starting real-time ranging, wherein the mobile beacon transmits a synchronization packet and a ranging packet in the ranging process, and a ranging result returned by the fixed tag is received;
step 403), loading the historical coordinates of the fixed beacon from the map information table as the initial value of the triangular synchronous positioning algorithm when the ranging result returned by the fixed beacon is received once;
step 404) calculating the space coordinates of the mobile beacon and the surrounding fixed beacons simultaneously by using a triangular synchronous positioning algorithm;
as shown in fig. 11, 5 fixed beacons: fixed beacon a, fixed beacon B, fixed beacon C, fixed beacon D, and fixed beacon E; the triangle synchronous positioning algorithm is based on triangle positioning and least square;
and (3) listing a distance equation between beacons, and subtracting the distance equation with the ranging result to obtain an error term:
wherein (x)1,y1,z1) To move the position of the coordinate, (x)a,ya,za) Coordinate value of fixed beacon A for sending ranging result to mobile coordinate; (x)1,y1,z1)、(xa,ya,za)、…、(xe,ye,ze) Is a parameter to be solved; the result of the ranging between the fixed beacon and the mobile beacon, the result of the ranging between the fixed beacons, is a known parameter, ea1Waiting for an error; e.g. of the typeabWaiting for an error;
solving 6 space positions (x) satisfying the minimum sum of squares f of all error terms by using a nonlinear optimization method (such as gradient descent, Newton iteration and conjugate gradient method)1,y1,z1)、(xa,ya,za)、…、(xe,ye,ze)：
The coordinate values of the fixed beacons recorded in the map information table can be used as the initial iteration values, and the fixed beacons not recorded in the map information table can randomly generate a group of coordinate values as the initial iteration values.
Step 405) will calculate the spatial coordinates (x) of the 5 fixed beaconsa,ya,za)、…、(xe,ye,ze) Updating the information in the map information table and outputting the positioning information (x) of the mobile beacon1,y1,z1)；
Finally, it should be noted that the above embodiments are only used for illustrating the technical solutions of the present invention and are not limited. Although the present invention has been described in detail with reference to the embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the spirit and scope of the invention as defined in the appended claims.
Claims (9)
1. A decentralized beacon location system comprising: a plurality of fixed beacons, and a mobile beacon,
the fixed beacon is in a calibration mode or a base station mode, and when the fixed beacon is in the calibration mode, a distance information table is established and the distance information between the fixed beacon and the surrounding fixed beacons is stored; providing ranging information and a range information table for the mobile beacon when in the base station mode;
the mobile beacon is in a calibration mode or a positioning mode, and when the mobile beacon is in the calibration mode, a map information table is established and original point information of a coordinate system set by the mobile beacon and space coordinates of a fixed beacon communicated with the mobile beacon in the coordinate system are stored; when the positioning mode is in, the self and the fixed beacon communicated with the self are positioned by using the ranging information, the distance information table and the map information table of the fixed beacon communicated with the self, the map information table is updated by using the positioning result of the fixed beacon, and the self positioning information is output.
2. The decentralized beacon locating system according to claim 1, wherein the fixed beacon is provided with a first channel and a second channel,
the first channel is used for sending and monitoring a state information packet; the status information packet includes: a heartbeat packet, a synchronization packet, a ranging result packet, a trigger packet, a repeat packet and a confirmation packet;
the second channel is used for sending and monitoring the ranging packet in a calibration mode; in the base station mode, ranging packets, which are a series of encoded time sequences used to calculate the time of flight of the signal, are monitored.
3. The decentralized beacon locating system according to claim 2, wherein the fixed beacon is configured to listen via the first channel to a heartbeat packet containing a fixed beacon ID number; the fixed beacon is also used for monitoring heartbeat packets sent by other fixed beacons, and when the heartbeat packets of other beacons are received, whether the heartbeat packet is the first received heartbeat packet of the beacon is judged; if yes, entering a calibration mode; otherwise, continuously monitoring heartbeat packets sent by other fixed beacons.
4. The decentralized beacon locating system according to claim 3, wherein the current fixed beacon is designated as fixed beacon A, and the fixed beacon receiving the first heartbeat packet is designated as fixed beacon B; when the fixed beacon a is in the scaling mode, the fixed beacon a performs the following steps:
the fixed beacon A periodically sends a synchronization packet to the fixed beacon B through a first channel, and simultaneously sends a ranging packet to the fixed beacon B through a second channel;
after receiving the synchronization packet and the ranging packet, the fixed beacon B starts to calculate the distance between the fixed beacon B and the fixed beacon A;
after the calculation is successful, the fixed beacon B sends the ranging result to the fixed beacon A through a first channel of the fixed beacon B;
after receiving the ranging result of the fixed beacon B, the fixed beacon A sends a trigger packet through a first channel of the fixed beacon A;
after receiving the trigger packet, the fixed beacon B periodically transmits a synchronization packet to the fixed beacon A through a first channel of the fixed beacon B, and simultaneously transmits a ranging packet to the fixed beacon A through a second channel of the fixed beacon B;
after receiving the synchronization packet and the ranging packet, the fixed beacon A calculates the distance between the fixed beacon A and the fixed beacon B as a calculated ranging result;
the fixed beacon A judges whether the difference between the ranging result sent by the fixed beacon B and the calculated ranging result is smaller than a threshold value; if the judgment result is positive, sending a confirmation packet to the fixed beacon B, storing the calculated ranging result into a distance information table, and exiting the calibration mode; otherwise, sending the repeated packet and re-entering the calibration mode.
5. The decentralized beacon locating system according to claim 3, wherein when the fixed beacon is in the base station mode, the fixed beacon performs the steps of:
monitoring a synchronous packet sent by a mobile beacon in real time;
after receiving the synchronous packet of the mobile beacon, calculating the distance between the mobile beacon and the synchronous packet of the mobile beacon as a ranging result;
and sending the ranging result and the locally stored distance information table to the mobile beacon.
6. The decentralized beacon locating system according to claim 5, wherein the mobile beacon is provided with a first channel and a second channel;
the first channel is used for sending a synchronization packet containing coding information and receiving an information packet containing a ranging result sent back by the fixed beacon; the coded information comprises the ID number and the time sequence number of the mobile beacon;
the second channel is used for transmitting a ranging packet containing codes; a ranging packet is a series of encoded ranging signals that contain a beacon ID.
7. The decentralized beacon locating system according to claim 6, wherein when the mobile beacon is in the targeting mode, the mobile beacon performs the steps of:
step S1) sending a synchronization packet through the first channel, and sending a ranging packet through the second channel;
step S2), monitoring the ranging result packet of the fixed beacon through the first channel, and when the number of the received ranging results meets the positioning requirement: the number of three-dimensional positioning is more than 3, and the number of two-dimensional positioning is more than 2; proceeding to step S3);
step S3) configuring a coordinate origin and a coordinate system; calculating space coordinates of the mobile beacons and the fixed beacons under the coordinate system by adopting a triangular synchronous positioning algorithm according to ranging information sent by the fixed beacons and distance information among the fixed beacons in a distance information table;
step S4), calculating the coordinate position of the mobile beacon through the ranging information for a plurality of times, and checking whether the positioning precision meets the requirement; if yes, go to step S6), otherwise, go to step S5);
step S5) adds a fixed beacon around the mobile beacon or changes the position, and proceeds to step S2);
step S6) writes the coordinate position of the mobile beacon into the map information table as the origin of the coordinate system, and writes the space coordinate of the fixed beacon communicating with the mobile beacon into the map information table in the coordinate system, and shifts to the positioning mode.
8. The decentralized beacon locating system according to claim 7, wherein when the mobile beacon is in the locate mode, the mobile beacon performs the steps of:
sending a synchronization packet through a first channel, and simultaneously sending a ranging packet through a second channel;
receiving a ranging result returned by the fixed beacon, and loading a coordinate value of the fixed beacon from a map information table;
taking the coordinate values and the ranging results of the loaded fixed beacons as initial values, and simultaneously calculating the space coordinates of the mobile beacons and the surrounding fixed beacons by adopting a triangular synchronous positioning algorithm;
and rewriting the space coordinates of the surrounding fixed beacons into a map information table, and outputting the positioning information of the mobile beacons.
9. The decentralized beacon positioning system according to claim 8, wherein the coordinate values and the ranging results of the loaded fixed beacons are used as initial values, and spatial coordinates of the mobile beacons and the surrounding fixed beacons are calculated simultaneously by using a triangulation synchronization positioning algorithm; the method specifically comprises the following steps:
and (3) listing a distance equation between beacons, and subtracting the distance equation with the ranging result to obtain an error term:
wherein (x)0,y0,z0) To move the position of the coordinate, (x)i,yi,zi) I is more than or equal to 1 and less than or equal to N, and N is the number of the fixed beacons for sending the ranging result to the mobile coordinate; (x)0,y0,z0) And (x)i,yi,zi) Is a parameter to be solved; ranging result d between fixed beacon and mobile beaconi0Ranging result d between fixed beaconsijIs a known parameter, wherein the range d between fixed beaconsijObtaining the distance information through a distance information table;
to fix the actual distance between the beacon and the mobile beacon,
is an error;
is the actual distance between the ith and jth fixed beacons,
is an error;
solving N +1 space positions (x) satisfying the minimum sum of squares f of all error terms by using a nonlinear optimization method0,y0,z0)、(x1,y1,z1)、…、(xN,yN,zN)：
The coordinate values of the fixed beacons which are recorded in the map information table can be used as the initial iteration values of the fixed beacons, and the coordinate values of the fixed beacons which are not recorded in the map information table can be randomly generated to be used as the initial iteration values of the fixed beacons;
the space coordinate (x) of the surrounding fixed beacon is calculated1,y1,z1)、…、(xN,yN,zN) Updating the information in the map information table and outputting the positioning information (x) of the mobile beacon0,y0,z0)。
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110171457.9A CN112986898B (en) | 2021-02-08 | 2021-02-08 | Decentralized beacon positioning system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110171457.9A CN112986898B (en) | 2021-02-08 | 2021-02-08 | Decentralized beacon positioning system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112986898A CN112986898A (en) | 2021-06-18 |
| CN112986898B true CN112986898B (en) | 2021-10-26 |
Family
ID=76347430
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110171457.9A Active CN112986898B (en) | 2021-02-08 | 2021-02-08 | Decentralized beacon positioning system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112986898B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116261216B (en) * | 2023-03-08 | 2023-10-20 | 无锡真源科技有限公司 | Automatic registration method and system for positioning beacon point |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101750598B (en) * | 2008-12-03 | 2012-06-27 | 中国科学院自动化研究所 | Wearable indoor positioning system based on radio frequency identification technology and method thereof |
| CN103200675A (en) * | 2013-03-25 | 2013-07-10 | 哈尔滨工业大学深圳研究生院 | Wireless sensor network target locating method and locating system without need of node self-localization |
| KR20170091811A (en) * | 2016-02-01 | 2017-08-10 | 목포대학교산학협력단 | An indoor positioning method using the weighting the RSSI of Bluetooth beacon and pedestrian pattern |
| US11448509B1 (en) * | 2018-12-22 | 2022-09-20 | Yoon Phil Kim | System and method for facilitating limited area GPS |
| CN111796238A (en) * | 2020-07-15 | 2020-10-20 | 长春奥普光电技术股份有限公司 | Positioning method and positioning system for indoor environment navigation |
| CN112147579B (en) * | 2020-09-24 | 2021-05-18 | 北京奥特雷柏科技有限公司 | Ultrasonic positioning system based on composite ultrasonic signal |
-
2021
- 2021-02-08 CN CN202110171457.9A patent/CN112986898B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN112986898A (en) | 2021-06-18 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102204372B (en) | Indoor localization system for locating electronic mobile device within indoor environment | |
| JP6940214B2 (en) | Positioning system | |
| JP4574945B2 (en) | Method and apparatus for position measurement | |
| Zhang et al. | Rass: A real-time, accurate, and scalable system for tracking transceiver-free objects | |
| Chenji et al. | Toward accurate mobile sensor network localization in noisy environments | |
| US9247388B2 (en) | Cooperative localization of radio apparatuses | |
| JP5420245B2 (en) | Client device auxiliary location data acquisition method | |
| WO2008115209A2 (en) | Cooperative localization for wireless networks | |
| Ahmadi et al. | Range free localization in wireless sensor networks for homogeneous and non-homogeneous environment | |
| CN101110713A (en) | Information anastomosing system performance test bed based on wireless sensor network system | |
| JP2018059932A (en) | Radio sensor network position specification system and method | |
| Mondinelli et al. | Self-localizing sensor network architectures | |
| EP1873978B1 (en) | Transmission range adjustment according to network conditions | |
| CN101635654B (en) | Method, device and system for measuring network traffic | |
| CN102215564A (en) | Method and system for positioning wireless sensor network | |
| CN101854716B (en) | Node locating method and communication device | |
| Sichitiu et al. | Simple Algorithm for Outdoor Localization of Wireless Sensor Networks with Inaccurate Range Measurements. | |
| CN112986898B (en) | Decentralized beacon positioning system | |
| CN102395198A (en) | Signal intensity-based node positioning method and device for wireless sensing network | |
| Dardari et al. | A sub-optimal hierarchical maximum likelihood algorithm for collaborative localization in ad-hoc network | |
| CN103402255B (en) | A kind of improvement DV-Hop localization method based on the weighting of corrected value error | |
| KR100940006B1 (en) | Apparatus and method for node localization in wireless networks | |
| CN112954591B (en) | Cooperative distributed positioning method and system | |
| Aruna et al. | Optimized path planning mechanism for localization in wireless sensor networks | |
| CN112379328A (en) | Robust TDOA (time difference of arrival) positioning method with low power consumption and robust median filter |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |