RU2540799C1 - Method of determining coordinates of mobile object in closed facilities - Google Patents

Abstract

FIELD: physics.

SUBSTANCE: method of determining coordinates of a mobile object in closed facilities relates to automation and computer engineering and can be used in systems for determining coordinates of mobile objects - warehouse operators, cargo and miners, where in facilities (mines, warehouses), the required number of passive radio-frequency identifiers is installed on building structural components, into which codes of coordinates of said radio-frequency identifiers (in a local coordinate system) are input; readers with codes of mobile objects are installed on the mobile objects; the power level of the signal emitted by the reader is reduced in proportion to the cube of the doubled error in determining coordinates of the mobile object.

EFFECT: high accuracy and low power consumption.

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Description

Technical field

The invention relates to automation and computer technology and can be used in the construction of automated warehouse management systems, namely to facilitate the search for goods, in the search systems for miners in mines after accidents, tracking the movements of personnel of protected and important objects in the premises.

State of the art

There is a known method of identifying an object in which identifiers are located in people (moving objects), one reader is built into the lock (reading point), the reader contains a local area network controller connected to a central computer (B. Malosevich. Contactless identification. - g. "CHIP NEWS" . - 2000. No. 8 (51), pp. 25-30).

This article describes the principle of operation of contactless radio frequency identifiers.

Electronic tags (identifiers) are made on the basis of integrated circuits without a housing, manufactured according to CMOS technology. Such a microcircuit has a permanent storage device (memory) or a reprogrammable memory in which the identification number of the object and its other characteristics are recorded. Radio-frequency identifiers are produced by Angstrem OJSC in Zelenograd. Microcircuits together with the transmitting and receiving antenna can be installed in various cases in the form of a plastic card, key fob, keyfob, disk, tablet label. The case design is determined by the purpose of the radio frequency identifier.

Plastic cards are produced for making passes in authorized access systems, tags for stickers on products in supermarkets and warehouses, key fobs for identifying keys or other valuable items, tokens for covert installation in products, tablet labels for covert installation in products. Tokens and tags can be installed covertly in concrete or painted over in the product, which makes it difficult to remove them to depersonalize the product.

For remote reading of RFIDs, RFID readers are used. The reader performs the following functions:

- emits an unmodulated signal at a given frequency (880-900 MHz);

- thereby supplies the integrated circuits (ICs) of the identifier with electrical power;

- thereby stimulating the IC to the formation of the response message recorded in her identification code in the form of a modulated amplitude of the radio signal;

- receives a radio signal, remembers an identifying code and has the ability to rewrite this code into a controller or electronic computer (computer) identification system;

- notifies the operator through a light indication and an audio signal about the recording of the response message.

Readers are connected via cable or radio channel to portable or stationary terminals.

The disadvantage of this method of determining the coordinates is that the location coordinate of the reader is determined. For example, when entering a protected area, an employee brings his pass to the reader, the reader reads the pass code, sends it over the local network to the central computer, where this code is checked to restrict the employee’s access to this room. The computer sends a door lock unlock code. In this case, the computer records the time, employee code, room number in which the employee is located in the database. In other words, the coordinates of the employee (as an object) are determined accurate to the size of the room, enterprise. Another disadvantage is the need for a person to interact with the RFID with the reader by manually approximating the pass (card) with the built-in RFID to the reader.

There is a method of identifying an object in which radio frequency identifiers are installed on the sides of moving objects (cars or containers), the reader is installed on the border of the railway station near the railway tracks (reading point), the reader contains a local area network controller connected to the central computer (Automatic container identification system and vehicles "PALMA". - Promotional brochure CNIRTI, Moscow).

The advantage of this method is the remote reading of information by the reader from the radio frequency identifier. The reading distance is 13 m with an autonomous power supply as part of the radio frequency identifier (active radio frequency identifier) and 5 m without a power source (passive radio frequency identifier). The disadvantage of this method is that it is aimed at identifying (determining the number and accessories) of railway cars, containers, vehicles and identifies the point of identification without determining the coordinates of the reader, i.e. the accuracy of the coordinates of the object (car) is equal to the size of the railway station itself and its entire area under the tracks (several km ² ).

The closest in technical essence to the claimed proposed invention (prototype) is a method for determining the coordinates of the position of a moving object in enclosed spaces, in which a reader is attached to the moving object, which is connected to a radio modem in the memory of which the code of the moving object is entered, electronic elements are fixed on the building structures identifiers at distances from each other, the values of which are defined as the doubled error in determining the coordinates of the position of the moving object a) the position coordinates codes of these electronic identifiers in the room coordinate system and their numbers are stored in the computer memory, the moving object is moved around the room, the number codes of these electronic identifiers are read remotely from the electronic identifiers memory, the number codes and the code of the moving object are transmitted via the radio modem on the computer’s radio modem, in which the coordinates of the position of the moving object in indoors. (Mayorov B.G. A method for determining the coordinates of a moving object in enclosed spaces. Patent for invention No. 2284542, BI No. 27, 2006)

The advantage of this method lies in the ability to determine the position of a moving object with an accuracy equal to the difference in the coordinates of two adjacent identifiers installed on structural elements of the enclosed space (up to fractions of a meter).

The disadvantage of this prototype method is that it determines the coordinates of a moving object with an accuracy equal to the difference between the coordinates of two adjacent identifiers installed on structural elements of an enclosed space (up to fractions of a meter), provided that the reader can successfully read the identifiers by communication between the identifier and reader antennas. If this distance is large, then the identifiers will not be read by the reader. At a small distance, several adjacent identifiers in the reading zone will be read at the same time, and the reader must implement an anti-collision algorithm to specify the sequence for reading identifiers. To determine the specific identifier (and its installation coordinates) closest in distance to the reader, it is necessary to implement additional algorithms for sorting the coordinates of the read identifiers to find the average coordinates. All these operations complicate the firmware implementation of the method and reduce the accuracy of determining the coordinates.

The reader supplies energy to the electronic identifiers located in its reading area, receives the codes of the numbers of these electronic identifiers via the radio channel, and transmits the codes of the numbers and the code of the moving object to the computer via the radio. The hardware implementation of these operations requires energy, the supply of which is limited for the wearable version of the design of the mentioned equipment, which leads to a decrease in the operating time of the autonomous wearable equipment.

SUMMARY OF THE INVENTION

The proposed method for determining the coordinates of the position of a moving object in enclosed spaces allows determining the position of a moving object with an accuracy equal to the difference between the coordinates of two adjacent identifiers mounted on structural elements of a closed room (up to several centimeters), that is, to increase accuracy and reduce energy costs or increase time operability of autonomous wearable equipment.

In the known method, a reader is fixed on a moving object, which is connected to a radio modem in whose memory the moving object code is entered, electronic identifiers are fixed on building elements at distances from each other, the values of which are defined as the doubled error in determining the coordinates of the position of the moving object, position coordinate codes these electronic identifiers in the coordinate system of the room and their numbers are recorded in the computer memory, move the moving object around the room, using chityvatelya read remotely from the memory of the electronic identity code numbers of electronic IDs, is transmitted through the radio codes and code numbers of the mobile object on the radio is a computer, which is determined by the appropriate code number ID and the coordinates of its position indoors position coordinates of the moving object in the room.

The purpose of this invention is to solve a new scientific and technical problem, namely, increasing the accuracy of determining the coordinates of a moving object to the distance between two adjacent fixedly fixed passive radio frequency identifiers (up to several centimeters) and reducing energy costs or increasing the uptime of autonomous, wearable equipment. To do this, passive electronic identifiers are installed in the premises (mines, warehouses), on the elements of building structures, the power level of the signal emitted by the reader is adjusted in proportion to the cube of the doubled error in determining the coordinates of the position of the moving object.

The method of determining the coordinates of the position of a moving object in enclosed spaces can be implemented so that in rooms (mines, warehouses), passive radio-frequency identifiers are fixed on structural building elements, in which the numbers codes of these electronic radio-frequency identifiers are entered, on a moving object (person, vehicle , cargo), a reader is fixed, which is connected to a radio modem, in the memory of which a moving object code is entered, the power level of the signal emitted by the reader is adjusted by the proportional cube of the doubled error in determining the coordinates of the position of the moving object, during the movement of the moving object, the reader interacts remotely with passive radio-frequency identifiers, receives from them the codes of the numbers of these radio-frequency identifiers, transmits the number codes and the code of the moving object through the radio modem to the central computer, in which it determines through the correspondence of the code of the identifier number and the coordinates of its position in a closed room, the coordinates of the position of the moving object but indoors.

The problem of determining the coordinates of the position of a moving object in enclosed spaces and increasing the accuracy of determining these coordinates to the distance between two adjacent fixed radio frequency identifiers is solved without using the global satellite positioning system (Global Positioning Sistem - GPS), which is widely used to determine the coordinates of the position of cars on highways and other vehicles. Fixed a significant drawback of the GPS system - the inability to determine the coordinates of a moving object when it is indoors: in a warehouse, in a hangar, in a tunnel. This is due to the effect that satellite navigation signals transmitted by the system’s satellites are not received by the satellite antenna installed on the moving object, due to the shielding properties of the main walls, roofs of buildings, and the thickness of the earth.

To determine the coordinates of moving objects in the prototype method, passive radio-frequency identifiers (without autonomous power sources) and wearable readers are used, a unique code number of this identifier is recorded in a passive electronic identifier inside the warehouse, mine, tunnel. In a portable reader located on a moving object, write the code of the moving object.

It is proposed to adjust the power level of the signal (downward) emitted by the reader in proportion to the cube of the double error in determining the coordinates of the position of a moving object.

This adjustment allows you to activate (supply energy) only those passive electronic identifiers that are located in the immediate vicinity of the reader or a moving object on which the reader is mounted. The coordinates of the installation of these identifiers coincide with the coordinates of the moving object at a given time.

In this regard, only this small number of identifiers will send response information messages to the reader, which will accelerate the implementation of the anti-collision algorithm in the reader controller. The implementation of these algorithms is outlined in the monograph: Sandeep Lahiri. RFID Implementation Guide. Per. from English - M .: KUDITS-PRESS. - 2007. - 312 p., Ill.

Since a portable portable reader is used, a decrease in the power level of the signal emitted by the reader is consistent with an increase in the accuracy of determining the coordinates of a moving object by reducing the interaction distance of the reader with the identifiers, which in turn leads to energy savings of the stand-alone portable reader and radio modem and increases the time of their stand-alone work.

Firms manufacturers of readers and identifiers that are used for a known purpose for solving warehouse problems, are struggling to increase the distance of reading information about the characteristics of the cargo (sender, brand, purpose, terms and conditions of storage, recipient, etc.).

When solving the problem of determining the coordinates of moving objects using passive electronic identifiers to the reading range of these identifiers by readers, the requirement arises of the need to reduce the reading distance.

This contradiction arises from the different purpose of the measurement information about the coordinates of the position of the cargo in the coordinate system of the warehouse and warehouse information about the cargo. Determining the coordinates of the position of the cargo during its delivery to the storage location in the warehouse and storing them in a computer is easier later (with less time) to find the necessary cargo in the warehouse.

List of drawings

Figure 1 shows a system for implementing a method for determining the coordinates of the position of a moving object in enclosed spaces.

Figure 2 shows a diagram of the interaction of the reader (mounted on a person’s belt) and passive radio frequency identifiers located in the floor of the room.

Figure 3 shows a diagram of the relative position of the reader and passive radio frequency identifiers located in the floor, on the walls, on the ceiling of the room.

Figure 4 shows the dependence of the radiation power P ₁ (r), P ₂ (r) of the reader 2 on the distance r between the measurement boundary and the antenna of the reader 2 at different initial radiation powers P ₁ (0), P ₂ (0).

An example embodiment of the invention

In figure 1, figure 2, figure 3 marked passive RF identifier 1, reader 2, electronic computer (computer) 3, radio modem 4.

The method of determining the coordinates of the position of a moving object in enclosed spaces is implemented as follows. A plan of a building, warehouse, or mine is being prepared (or taken). The distances according to this plan are measured between passive radio frequency identifiers 1, which should serve as coordinate marks. For example, for a warehouse (hangar), in which there are no internal partitions, you can put a grid on the plan with a constant step between the cells. In the coordinate system of this plan, the coordinates of these cells are determined. In the passive radio frequency identifiers 1 write their serial numbers, identifiers 1 are marked accordingly. Appropriate marking is made on the floor and holes are drilled into which the corresponding identifiers 1 are laid, holes are concreted. You can pull a wire under the ceiling, on which to fix identifiers 1. In the shaft, identifiers 1 can be fixed with a corresponding step on the ceiling of the drift.

Figure 1 shows a system for implementing the method, in which the passive radio-frequency identifiers 1 write down the codes of their serial numbers in the structure and fix on building structures. In the memory of the reader 2, the code of the moving object (warehouse operator, miner, important cargo, loader) is recorded and the power level of the signal emitted by the reader 2 is adjusted in proportion to the cube of the doubled error in determining the coordinates of the position of the moving object. The reader 2 is fixed, respectively, on a loader, on a person’s belt, on a load. The reader 2 periodically emits an unmodulated signal at a given frequency (880-900 MHz) - thereby supplying the nearest passive radio frequency identifiers 1 with electrical power.

Having received the energy, the radio frequency identifier 1 forms a response message of the sequence number code recorded in its memory in the form of a modulated radio signal in amplitude. The reader 2 receives the radio signal, remembers the code of the serial number and sends this code and the code of the moving object through the transmitting radio modem 4 to the receiving radio modem 4 in the computer 3. Information is processed by establishing the correspondence of the code of the serial number of the identifier and its coordinates on the digital plan of the closed room, is stored and displayed on the computer monitor 3 together with the plan of the building (structure). Thus, the position of the moving object in an enclosed space is continuously monitored over time.

Such information can be of particular importance for monitoring and recording the work of warehouse personnel and arsenals with especially hazardous equipment, as the position of such equipment in the room will be monitored continuously.

We show the need for the operation of adjusting the power level of the signal emitted by the reader 2, in proportion to the cube of the double error in determining the coordinates of the position of the moving object.

Figure 2 shows the interaction diagram of the reader 2 (mounted on the belt of a person, conventionally depicted as an eight-pointed star) and passive radio frequency identifiers 1 (located in the floor of the room, conventionally depicted as five-pointed stars). The distances between adjacent RF identifiers 1 are set equal to each other (DE = DF) when they are installed. Distances are equal to twice the error in determining the coordinates of the position of the moving object DE = DF = 2Δ. This corresponds to the fact that the measurement error is equal to half the minimum scale division of the measuring device. For this case, the scale of the device is formed by radio frequency identifiers 1, mounted in the floor of the room. The antennas of readers 2 are structurally performed with linear and circular polarization (Sandeep Lahiri. RFID. Implementation Guide. Translated from English. - M.: KUDITS-PRESS - 2007. - 312 pp., Ill.). Linear polarization gives a reading plane and allows you to read not all identifiers, but only those that are oriented in a certain way relative to the antenna. For this reason, consider a circular polarized antenna. The antenna forms an electromagnetic field in the form of a body of an ellipsoid of revolution (Fig. 2 is depicted by a dash-dotted line), the intersection of which with the plane of identifiers 1 (floor) gives a reading circle (in Fig. 2 it is visible in a side projection in the form of two segments of a straight line AD and DC) . The reader 2 is suspended from a person’s belt at a height of h. With increasing power of the signal emitted by the reader 2 (the person is stationary), the size of the ellipsoid of rotation will increase and the reading circle will capture more than one identifier 1 set at point D, as well as identifiers 1 at points E and F and beyond. This leads to the time spent on the anti-collision algorithm in the reader controller 2 and the additional power of an autonomous power source to generate radiation of excessive power.

It is proposed to adjust the radiation power of the reader so that the boundaries of the reading circle of reader 2 are at the midpoints of the distances DE = DF between adjacent identifiers 1: at points A and C. This condition ensures that the identifier 1 installed at point D is supplied with the energy necessary to form response code message to the reader 1. This condition ensures that there is no energy for generating response code messages by identifiers 1, set at points E and F. When this condition is fulfilled, Lnik ABC is an equilateral sides with the value

$$r=2\Delta .\text{(one)}$$

Moreover, the height h of the reader 2 suspension to the person’s belt (on the vehicle) is associated with the doubled error in determining the coordinates of the position of the moving object 2Δ by the expression

$$h=2\Delta \sin {60}^{\circ }=\sqrt{3}\Delta \text{or}\Delta =\text{h /}\sqrt{\text{3}}.\text{(2)}$$

It follows from expressions (1) and (2) that r> h. This condition is necessary to provide identifier 1 at point D (see FIG. 2) with some margin for unconditionally generating identifier 1 of the response code message to reader 2. Expression (1) defines the measurement boundary (“arrow thickness” of the measuring device).

Expression (2) allows us to illustrate the dependence of the error in determining the coordinates of a moving object D on the relative position of the reader 2 and identifiers 1, mounted on the elements of building structures.

Figure 3 shows a diagram of the relative position of the reader 1 and passive radio frequency identifiers 2 located in the floor, on the walls, on the ceiling of the room (corridor).

Table 1 shows the mentioned options for the mutual arrangement of the reader 1 and passive RFIDs 2 with the necessary expressions (similar to (2)) and calculation examples for the corridor width K = 400 cm, ceiling height H = 300 cm.

Table 1 N Identifier Installation Surface Reader Mounting Location Reader suspension height h, cm The accuracy of determining the coordinates Δ, cm Number of identifiers per risk of measurement scale n, pcs. one 2 3 four 5 one Gender (pl) Man's belt 100.0

$${\Delta }_{Pl}=h/\sqrt{3}\approx 58$$

$$n_{Pl}=\sqrt{3}K/2h\approx \mathrm{four}$$

2 Gender (pl) Loader chassis 10.0 Δ _pl ≈6 n _pl ≈35 3 Wall (s1) Belt or chassis - $${\Delta }_{\mathrm{from}\mathrm{one}}=K/\sqrt{3}\approx 231$$

n _c1 = 1 fourteen Two walls (c2) Belt or chassis - $${\Delta }_{\mathrm{from}2}=K/2\sqrt{3}\approx 116$$

n _c2 = 2 5 Ceiling (pt) Man's belt 100.0 $${\Delta }_{Pt}=\left(H-h\right)/\sqrt{3\approx 116}$$

$$n_{Pt}=\sqrt{3}K/2\left(H-h\right)\approx 2$$

6 Ceiling (pt) Miner's helmet 170.0 Δ _fr ≈75 n _fr ≈3 7 Ceiling (pt) Loader cab roof 230,0 Δ _Fri ≈41 n _fr ≈5

From columns 3 and 4 of table 1 it is seen that reducing the distance between the reader 1 and identifier 2 leads to a decrease in the error in determining the coordinates of a moving object. Column 5 of table 1 shows that the decrease in error (increase in accuracy) is associated with the need to install a large number of identifiers 1 at one risk of the measurement scale. So, for the case of mounting the reader 2 on the chassis of the loader (row 2 of table 1), at a distance of 10 cm from the floor, it will be necessary to install a grid of passive identifiers 1 in 12 cm increments. In this case, one row of passive identifiers 1, perpendicular to the corridor wall ( across the corridor), will contain about 35 identifiers 1. At the same time, the coordinates of the loader will be determined with an accuracy of 6 cm.

If two identifiers 1 are installed on two opposite walls of the corridor (row 4 of table 1), the same codes are written in these identifiers 1, and the power level of the signal emitted by the reader is adjusted in proportion to the cube of the doubled error in determining the coordinates of the position of the moving object. In other words, both passive identifiers 1 will receive power from the reader 2 and transmit the response code message to the reader 2 if the reader 2 (and the person) moves exactly along the midline of the corridor. At offsets to one of the walls, the nearest identifier 1 will interact with the reader 2.

Theoretically explain the need for the operation of adjusting the power of the signal emitted by the reader, in proportion to the cube of the double error in determining the coordinates of the position of the moving object.

We write down the dependences of the radiation power P ₁ (r) and P ₂ (r) of reader 2 on the distance r between the reading boundary and the antenna of reader 2 (Sandeep Lahiri. RFID. Implementation Guide. Translated from English - M.: KUDITS-PRESS. - 2007. - 312 p., Ill.)

$$P_{\mathrm{one}}\left(r\right)=\frac{K}{{\left(r+r_{01}\right)}^3},{\text{P}}_{\text{2}}\left(r\right)=\frac{K}{{\left(r+r_{02}\right)}^3}\text{(3)}$$

where K is a coefficient depending on the design of the reader antenna;

r ₀₁ , r ₀₂ - coefficients that determine the levels of radiated power in the immediate vicinity of the antenna.

For r = -r ₀₁ , r = -r ₀₂ from (3) we have, respectively, P ₁ (-r ₀₁ ) = ∞ and P ₁ (-r ₀₁ ) = ∞ are hypothetical characteristics points (see Fig. 4) .

For r = 0 from (3) we obtain expressions for determining the levels of radiated power in the immediate vicinity of the antenna

$$P_{\mathrm{one}}\left(0\right)=\frac{\mathrm{TO}}{r_{01}^3},{\text{P}}_{\text{2}}\left(0\right)=\frac{\mathrm{TO}}{r_{02}^3},\text{(four)}$$

For r = ∞, from expressions (3) we have, respectively, P ₁ (∞) = 0 and P ₂ (∞) = 0 are the levels of radiated power at a large distance.

From expressions (3) we determine the distances r ₁ and r ₂ at which the radiated power levels of the reader 2 are equal to P ₁ (r ₁ ) and P ₂ (r ₂ ), respectively

$$r_{\mathrm{one}}=\sqrt[3]{\frac{\mathrm{TO}}{P_{\mathrm{one}}\left(r_{\mathrm{one}}\right)}}-r_{01},{\text{<figure-callout id="2" label="r" filenames="00000016.png,00000017.png" state="{{state}}">r</figure-callout>}}_{\text{2}}=\sqrt[3]{\frac{\mathrm{TO}}{P_2\left(r_2\right)}}-r_{02}.\text{(5)}$$

Figure 4 shows the dependence of the radiation power P ₁ (r), P ₂ (r) of the reader 2 on the distance r between the measurement boundary and the antenna of the reader 2 at various initial radiation powers P ₁ (0)> P ₂ (0) according to the expressions ( 3).

From expressions (4) we obtain the inequality P ₁ (0)> P ₂ (0) in the form

$$\frac{\mathrm{TO}}{r_{01}^3}>\frac{\mathrm{TO}}{r_{02}^3}\text{or}{\text{r}}_{\text{02}}^{\text{3}}>r_{01}^3.\text{(6)}$$

We set the equality P ₁ (r ₁ ) = P ₂ (r ₂ ) and take the difference in expressions (5), taking into account (6), we obtain

$$r_{\mathrm{one}}-{\mathrm{<figure-callout\; id="2"\; label="r"\; filenames="00000016.png,00000017.png"\; state="\{\{state\}\}">r</figure-callout>}}_2=r_{02}-r_{01}.\text{(7)}$$

We determine the necessary change in the level of radiated power by the reader 2 in the immediate vicinity of the antenna to reduce the radius of the reader 2 to r ₂ = 2Δ. For this we use expressions (4), (7) and (1) with r = r ₂ = 2Δ

$$\Delta P\left(0\right)=P_{\mathrm{one}}\left(0\right)-P_2\left(0\right)=\frac{\mathrm{TO}}{{\left(r_{01}{r}_{02}\right)}^3}\left(r_{\mathrm{one}}^3-8{\Delta }^3\right),\text{(8)}$$

where r ₁ is the maximum reading radius of reader 2, which is indicated in the passports for reader 2 and passive electronic identifiers 1;

r ₂ = 2Δ is the optimal distance at which the mandatory supply of identifier 1, installed at point D (see figure 2), is provided with the energy necessary to generate a response code message to reader 2.

The operation to reduce the power radiated by the reader 2 by ΔP (0) by expression (8) compared with the maximum radiation power of the reader 2 ensures that there is no energy for generating response code messages by identifiers 1 installed at points E and F (see Fig. 2).

Industrial applicability

The proposed method for determining the coordinates of the position of a moving object in enclosed spaces is industrially implemented, it allows constant monitoring of moving objects over time, with an accuracy of several centimeters, and significantly saves the energy of wearable readers 2 passive electronic identifier number codes 1. Allows you to speed up the search for miners after accidents in mines and streamline and speed up staff work in warehouses.

Claims (1)

A method for determining the coordinates of the position of a moving object in enclosed spaces, in which a reader is attached to a moving object, which is connected to a radio modem in whose memory the moving object code is recorded, electronic identifiers are fixed on structural elements at distances from each other, the values of which are defined as double the error determine the coordinates of the position of the moving object, the coordinates coordinates of the position of these electronic identifiers in the coordinate system of the room and their numbers they transfer it to the computer’s memory, move the moving object around the room, use the reader to read remotely from the electronic identifier’s memory the number codes of these electronic identifiers, transfer the number codes and the code of the moving object to the computer’s radio modem, in which they determine the identifier’s code number and its coordinates position coordinates of the position of the moving object in the room, characterized in that passive electronic identifiers are used, control the signal power level, the radiation aemogo reader proportional to the cube of the double error in determining the coordinates of the mobile object position.

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