DE102009010857A1 - Electronic article locating system for use in e.g. sales room, has measuring stations connected to base station, where total number of measuring stations is larger than number of to-be-determined coordinates of article-tag - Google Patents

Abstract

The system has a set of stationary measuring stations (111-114) and set of non-stationary measuring stations (121-128) connected to a base station (10) i.e. computer, where one of the non-stationary measuring stations is provided for determining coordinates of an article-tag (130) and a total number of measuring stations is larger than a number of to-be-determined coordinates of the article-tag. Results of triangulation are registered as gradual truth values in a two-dimensional or three-dimensional matrix. The base station emulates a fuzzy logic for evaluating gradual truth content. An independent claim is also included for a method for electronic article location by measuring signal propagation time between measuring stations and an article-tag attached to an article and by determining coordinates of the article-tag by triangulation.

Description

The The invention relates to an electronic article location for the automatic inventory of inventories, the same also for the management of sales areas, The theft protection in sales facilities as well as automatic Data collection at point-of-sales is appropriate.

Known is the use of RFID tags (radio frequency identification) for marking articles. The articles are for this purpose provided with RFID tags that are activated at readout stations and send a commodity identification number. Unless it's like this are called passive RFID tags without its own power supply, are this limited in range to a few tens of centimeters, which for an automatic check-out and check-in process is sufficient, but not for a location of the article in a warehouse or sales room. Limiting affects the range for activating the RFID tag. This results in Manipulation options, as with the known security labels for securing goods in sales areas have become known.

In the context of automatic inventory systems, methods are known, attached to the article labels in the form of article tags z. B. by triangulation (triangle determination) to locate. Active RFID tags are used which have their own power supply and thus solve the range problem. Such a wireless system for vending automation and advertising will be in the US2006 / 0163349 described. Several so-called access points are in radio communication with a tag and measure their position by triangulation in evaluation of signal propagation times.

In the US 6,959,862 A method for automatic inventory and article identification is proposed in which the tags attached to the article can also be measured by triangulation with respect to their position. The accuracy of the location depends on the length of the pulses used together. To achieve accuracies of less than 10 cm, for example, short pulses are required in fractions of nanoseconds.

The triangulation pulse method can be suitably combined with ultra-wideband information transmission (UWB) based on distance modulated pulses, for example in the frequency range of 3.1 to 9 GHz. A pulse-based Ultra-Wideband Smart Sensor Interface Network and Method US 7,075,476 determines the location of a sensor within buildings. To monitor prisoners is in the US 6,489,893 a system based on UWB. The respective location of the prisoner is measured with impulses. Upon entering a forbidden zone an alarm is triggered.

A so-called LIMIS system (Location, Identification, Measurement of Movement, Inventory) for the position analysis of tags or articles describes the US 4,656,463 , Especially dealing with the problem of the transition of a portable receiver from a UWB cell to an overlapping next cell is the US2003 / 0036374 ,

Within closed rooms proves the exact location of article tags by means of transit time measurement, as they are eg. For example Automatic inventory is required, but difficult. Occurring reflections on the walls and furnishings do not cause unambiguous results of the transit time measurement. There are Although solutions for receiver concepts are known, between directly received signals (line-of-sight LOS) and reflected Distinguish signals. A total extinction of the in direct line from the transmitter to the receiver Signal is not unlikely, especially if transmitter and receiver are at a certain distance.

Just Warehouses and salesrooms are characterized by a variety of furnishings, a direct line of sight between a base station and Prevent Article Tag. Location signals reach in particular at the high frequencies used do not go straight to the article tag, but if at all, in a roundabout way. This will be a bigger one Running time simulated as it corresponds to the direct distance.

task The invention is an arrangement and a method for electronic To propose item location, which is a tamper-proof location of tags affixed to the article also in closed spaces with multiple reflections and missing line of sight between guaranteed the article tag and the measuring station.

The The object is achieved by the characterizing features of claim 1 and the method according to independent claim 10 solved. Advantageous embodiments are defined by the subordinate claims detected.

The essence of the invention is that a tag is affixed to the article whose position in space is determined by a number of measuring stations whose total number is at least two greater than the number of coordinates of the article tag to be determined, where at least a the measuring stations can be moved. The determination of the position of the article tag takes place in two steps. First, the position of the at least one portable measuring station is determined by the stationary measuring stations with known spatial coordinates. Subsequently, the position of the article tags is determined using different combinations of measuring stations. Thus, more triangulations are performed, as they would actually be necessary to uniquely determine the position of an article tag in a free space or a free surface without reflections and absorptions.

The Results of the triangulation are according to the invention Method as gradual truth values in a two- or three-dimensional Matrix entered. The coordinates of the elements of the matrix correspond Grid points with discrete distances in real space or in the real area. Determined coordinates of the article tag are assigned to the nearest grid point. A Position is recognized as true if the gradual truth value at least 50% of the maximum possible truth value is. Compared with known systems of position measurement This results in a resistance to incorrect measurements, the caused by signal cancellations or reflections.

The Inclusion of measuring stations with variable position, hereinafter referred to as a portable measuring station, in the positioning of article tags at the same time secures high degree of flexibility. local Variable Measuring stations can be in different numbers everywhere be located there, where complicated room conditions a location also require hidden article tags. The spatial arrangement of portable measuring stations can be the changing conditions in warehouses or salesrooms to adjust. The update of the spatial arrangement can thereby be triggered periodically or as needed.

In Another embodiment of the invention signals an optical or acoustic signaling device on the article tag that does not provide adequate Number of measuring stations can be received. Through a change the position of the portable measuring stations, the Number of measuring stations received by the article tag on at least five for a three-dimensional location or four for a two-dimensional location determination increase.

In An embodiment of the invention has the article tags two operating states. In a power saving mode is through a watchdog only monitors a motion sensor with the lowest energy requirement. If a movement z. B. registered an acceleration changes the article tag into an operating state that is receiving and Sending information allows. This is the circumstance exploited that in the vast majority of the article is in a dormant state. There is no need to constantly polling the position of the article and so on Energy for sending and receiving information to consume.

In In another embodiment of the invention, the article tag falls back to sleep mode when the motion sensor no movement for a certain time.

In Another embodiment of the invention is the frequency determining the position of an article tag by values, which were determined by the motion sensor. A position determination takes place, for example, in very short time intervals, if the article moves at a high speed.

In A further embodiment of the invention become surfaces or rooms with different statuses defined, the different time intervals determine the position determination, So z. B. changing rooms, door areas.

In Another embodiment of the invention is a change of the operating state triggered by a timer. In this way, for. B. Inventories of an inventory prepared, which are made during a certain period of time should.

In Another embodiment of the invention is locating and Information transmission using a pulse-based ultrawideband transmission method combined. By using pulses with a width of some 100 picoseconds, the position is determined with errors less than 10 cm. By distance or phase modulation of this For example, these can be pulses of information at the same time to addresses, ID numbers, signal quality and results of time measurements.

In In another embodiment of the invention, the mechanical Attaching the article tag to the article in a known manner by opening a Closure removed. The security label can then be completed a charging process of the energy storage, provided with a new identification number, be circulated again.

The Invention will be explained with reference to embodiments become. Show it

1 Location by triangulation

2 Location by triangulation without line of sight

3 Location by permanently installed measuring stations and additional measuring station

4 Levels of item location system

5 Electronic functional assemblies of the article tag

6 Timing of communication between article tag and reference day

7 Article tag with timer

8th Function modules of the reference day

In 1 In a planar representation, the principle of the two-dimensional position determination of a location point P1 by measuring the propagation times and conversion into distances l _a1 , l _b1 , and l _{c1 is} shown. The considered area is defined by a real area 1 , ie a sales or a storage room, as well as a virtual area 2 educated. For a location by triangulation, ie triangulation, at least two measuring stations, for example B _S and C _{S are} necessary first, whose coordinates and thus their distance l _{bc are} known.

The determination of the triangle from the distances l _b1 , l _c1 and l _bc is ambiguous. Thus, in the exemplary geometric arrangement of the measuring stations B _S and C _S , the point S _1b , too, satisfies the track conditions in a virtual area. The ambiguity can be excluded if another measuring station A _{S is} introduced or if it can be determined that the point S _1b lies in a virtual area. With three measuring stations A _S , B _S and C _S , there are three possibilities, by triangulating the triangles A _S -B _S -P ₁ , B _S -C _S -P ₁ , A _S -S _S -P ₁ the point P ₁ which allows three more triangulations to yield additional points lying either in the real or virtual area. In the example executed by the diagram 1 the points S _1a and S _1b lie in a virtual area, whereas the point S _1c is the real area 1 assigned. Only the point P ₁ results identically from three triangulations, while the points S _1a , S _1b and S _1c each satisfy only one triangulation.

The method according to the invention will initially be explained for the two-dimensional location of a location point P ₁ . For this purpose on the real surface 1 a virtual network of halftone dots with discrete distances. Measured positions are assigned to the nearest grid point, hereinafter referred to as the measuring point. The spacing of the grid points corresponds to the required minimum accuracy of the position determination of article tags, wherein the actual measurement accuracy should be greater. The real area 1 in which the location is to be determined by tags, an area interval u · v forms discrete points. Measuring points whose position in the virtual area 2 can be ignored.

The mesh of halftone dots is now mapped by a computer to a matrix of u columns and v rows. Each detected measuring point, regardless of whether it reflects the correct position of the point P ₁ or whether it is to be assigned to a faulty measurement, is entered in the corresponding position of the matrix with a gradual truth content, for example of "1". If a measuring point with the same coordinates is found in the triangulation of the location point P ₁ with the help of another triangle, the truth content increases by a further value "1". The number of elements of the matrix corresponds to the number of possible measurement points for a location point that is arbitrarily positioned in the real area.

Become the gradual truth values of the arrangement 1 entered into a matrix with u columns and v rows, the following picture emerges:

In the described embodiment according to 1 is assigned to the matrix element (row 4, column 5) of the truth value "3", since all three triangulation of the point P have ₁ arise with different combinations of stations to the same measuring point. The point S _1c , since it could only be determined in a triangulation and thus appears only once in the area interval, has only the truth value "1".

In the described embodiment in 1 the coordinates of the measuring stations A _S , B _S and C _{S are} known. It is advantageous to arrange these three measuring stations on orthogonal lines with the greatest possible distance l _ab , l _bc and l _{ac in} order to reduce the computational effort or to increase the spatial resolution in the determination of the point P ₁ .

If the distances l _a1 , l _b1 , and l _c1 are determined only by determining signal propagation times, the Cartesian coordinates of the point P ₁ can also be determined by trigonometric functions. Starting from the determination of the position of the point P ₁ by the triangle B _S -C _S -P ₁ , the two Cartesian coordinates of the point P ₁ and the mirror point S1 result on the basis of the measured values for l _b1 and l _c1

In 2 a special case is considered in which there is no direct visual or radio connection between the measuring station A _S and the point P ₁ . This situation is caused by an absorber 4 and a reflector 5 indicated. The transit time of the signal from the measuring station A _S to the point P ₁ increases. Apparently the point P ₁ of the measuring station station is at a distance s _a1r . The triangulation thus yields a triangle A _S -B _S -P _1a , where measuring point P _{1a is} not identical to point P ₁ . Similarly, the triangulation in the triangle B _S -C _S -P _1b provides the measuring point P _1b , whose position also does not coincide with the position P ₁ . If the points thus determined are entered into a matrix as gradual truth values, the result is:

ermitteln lässt und k die Anzahl der Messstationen ist.An unambiguous identification of the point P ₁ is no longer possible since the pseudo points P1a and P1b as well as the mirror points S _1c lie in the real area and have identical truth values "1". It follows that further measuring stations are required, whereby the number of possible triangulations N _{2 is}

can be determined and k is the number of measuring stations.

In 3 An additional measuring station M _{S is} added to the three stationary measuring stations. For four measuring stations, this results in 12 possible triangulations. The maximum possible truth value is "6", whereby already a value of "3" can be regarded as sufficient for the determination of a true position P1. The predominant entries in the truth matrix should have the value "1", relatively unlikely is the value "2".

If the three-dimensional coordinates of a point P _{1 are to} be uniquely determined, at least four measuring stations with known coordinates whose positions may not lie in one plane are necessary. It is advantageous if one measuring station in the coordinate origin, the other three in the greatest possible distance on the three axes of a Cartesian coordinate system. The triangulation of the point P ₁ with two measuring stations initially supplies a circle, with three measuring stations two points are determined.

In Application of the method according to the invention is the room in which a location is to be made, a virtual network of grid points at discrete intervals. Each lead three measuring stations in different combinations a location through. The determined measuring points are again called gradual truth values into a now three-dimensional matrix entered with u columns, v rows, n columns, w levels. At four Measuring stations are a total of 8 three-dimensional triangulations possible, resulting in 8 measuring points. The maximum Truth value and minimum value for a safe Location is equal to "4" in this case.

The number of three-dimensional triangulations N ₃ in the combination of three measuring stations generally results from the number of measuring stations k with

With Five measuring stations are already 20 possible three-dimensional triangulations, the maximum truth value increased down to 10, which is already a good resistance to Absorption or reflections results.

The evaluation of matrices with gradual truth values can be carried out effectively with the known instrumentation of a fuzzy logic modeled on a computer. An application of the essence of the invention is also given when locating results are evaluated, which are subject to many reflections. As a result of this, entries of gradual truth values in the immediate vicinity of matrix elements can occur whose accumulation can likewise be evaluated or weighted.

The Arrangement of further stationary measuring stations, their coordinates must be known, seems inflexible and requires a high installation effort, especially since the establishment of a Sales or storage space can change constantly and also a variety of reflectors and absorbers are conceivable. According to the invention To achieve a high degree of flexibility both stationary measuring stations and used as well as mobile measuring stations, their characteristic feature is that their positions in comparatively short Intervals only on request or as part of a cyclical Initialization can be determined. The density is more mobile Measuring stations is thereby increased in particular where a Variety of reflectors and absorbers are expected to be on top of this Way to achieve high gradual truth values.

The initialization of a four - level article positioning system with the aid of stationary and mobile measuring stations is to be based on the exemplary scheme in 4 be explained. The three measuring stations 111 . 112 . 113 for a two-dimensional locating or four measuring stations 111 to 114 for a three-dimensional positioning stationary are advantageously arranged on the axes of a Cartesian coordinate system and known in their coordinates. The origin of the coordinates advantageously lies in a corner of the surface or space to be monitored.

The stationary measuring stations 111 to 114 are with a master 10 which also supplies the position values of all measuring stations and article tags to a higher-level merchandise management system. In one embodiment, it is assumed that the position of these stationary measuring stations 111 to 114 Very rarely, for example, every 100 days is changed, while the position of a portable measuring station can change quite within an hour. Eight more measuring stations 121 to 128 are as portable measuring stations in the real area 1 or to be monitored space arranged. Their position is therefore unknown at first.

In a two-dimensional position determination lead the stationary measuring stations 111 to 113 successively triangulations for determining the position of the portable measuring stations 121 to 128 by, wherein in the triangulation of the portable measuring station 124 For example, only a truth value of a maximum of "1" in contrast to the truth value "3" in the triangulation of the portable measuring station 123 is reached. The determination of the position of the portable measuring station 123 is therefore true, the position of the portable measuring station 124 is indifferent because, for example, no direct line of sight between the stationary measuring station 111 and the portable measuring station 124 consists.

In the second step of the initialization becomes the portable measuring station 123 with now verified position for determining the coordinates of the portable measuring station 124 used. With now four available measuring stations for a two-dimensional position determination, there are 12 possible triangulations, from which the position of the portable measuring station 124 with a truth value of at least "3" and a maximum of "6" can be determined. Since considerably more variants are available for triangulation here, it is very probable that all portable measuring stations can already be located in the second initialization step.

For the unlikely event that in the second initialization step not all portable measuring stations by reaching a truth value of at least "3" two-dimensional are located, further initialization steps are conceivable. These Approach can be continued arbitrarily, until the Surface in which a position determination is performed should be, with enough many portable, in their position known measuring stations is busy.

For the application of the method according to the invention However, it is advantageous if the number of possible Triangulations using optimal strategies as possible stays small. For example, it seems appropriate the number of triangulations in each initialization step in to keep it constant.

Supposed to be in an area, as in 4 shown, a total of 8 portable measuring stations, which are measured by three stationary measuring stations, the result in the first initialization step 72 triangulations. If, for example, only four portable measuring stations can be determined in position in the first initialization step, and if three stationary and two mobile measuring stations are used in the second initialization step, then another 80 triangulations result.

If, in turn, two spatially variable measuring stations are not determined in the second initialization step, in a third initialization step, in turn, the three stationary measuring stations and three spatially variable measuring stations become used with verified position. The three portable measuring stations should expediently not be the same as those used in the second initialization step and have the greatest possible distance to the stationary measuring stations. Thus, another 60 triangulations are performed to determine the two-dimensional position of the still unknown two portable measuring stations. Thereafter, it makes sense to abort the process, since it can be assumed that the position of the previously unlocated portable measuring stations is so unfavorable that their change in location is appropriate.

at The described example will be for the position determination of eight portable measuring stations in a two-dimensional Considering a total of 212 triangulations needed. The Number of necessary triangulations increases when many portable measuring stations located in three dimensions Need to become. For example, at similar Strategy, as for the two-dimensional location of eight Portable measuring stations described for the three-dimensional location of 100 portable measuring stations about 2000 triangulations needed. If after today State of the electronics estimate is that for a bidirectional connection in the GHz range approx. 1 ms needed requires a location of 100 portable measuring stations so several seconds to Minutes.

After completion of all necessary triangulations during the initialization process is in the base station 10 as a software simulation, a three-dimensional map with known positions of the portable measuring stations 121 - 128 and the possible routes over which the portable measuring stations 121 - 128 through the base station 10 can be achieved.

The functional assemblies of the portable measuring stations are in 8th shown. The UWB receiver 40 takes on the physical level, the modulation and demodulation of the signals including the signal amplification. Through the controller 40 The application manages the MAC protocol for data communication. The controller 40 can be on a system clock 46 for measuring transit times and a memory 45 to access data.

The Electronics of the portable measuring station leaves can accommodate one or two chips with suitable technology. Overall, this results in a compact design, which is a simple Change of location and easy attachment to home furnishings sales or storage space.

The simultaneous use of the portable measuring stations as tags for an item location or an automatic one Inventory is possible, but for energetic reasons not optimal. The use of the portable measuring stations also for the triangulation of other portable measuring stations requires a permanent operational readiness with permanent Radio traffic for forwarding location data. The for A UWB radio link needed electrical Power of for example 100 mW requires relatively large Energy storage, charged or replaced in short cycles or even an external power supply.

moreover is the direct use of the portable measuring stations for location of articles or goods relatively slow. If can still be assumed that the position of the portable Can change measuring stations at hourly intervals, are the dynamic requirements for tagging tags, which are attached to articles, much higher. Becomes an article z. B. moves unauthorized, it may be a reaction is required within one second. The implementation of several thousand triangulations in such a narrow time interval is with the available technological possibilities only possible with very high effort.

Furthermore, it has to be taken into account that, under certain circumstances, 10 ⁴ to 10 ⁵ tags must be located for a goods security in a sales room or for the automatic inventory in a warehouse, which initially does not seem possible with the described method for triangulation.

In a particularly advantageous embodiment of the invention will be accordingly 4 Therefore, another level of tags specifically for article tagging and location has been introduced, the particular feature of which is that these article tags only become active when movement of the article e.g. B. is detected by a motion sensor or activation by a timer occurs.

5 shows the functional assemblies of the article tag according to the invention. The UWB receiver 20 takes on the physical level, the modulation and demodulation of the signals including the signal amplification. A controller 40 is intended for administration of the application and for the execution of the MAC protocol of the data communication. The controller 40 can be on a system clock 26 for measuring transit times and a memory 25 to access data.

A particularly advantageous embodiment of the invention is the use of a watch dog 21 that a motion sensor 30 monitors and thus controls at least two operating states of the article tag. The motion sensor 30 can be performed as advantageous as a position sensor or acceleration sensor.

In a further embodiment of the invention, the article tag, as in 7 shown, to activate the watchdog 21 via a timer 31 , This allows the article tag to be activated at fixed intervals, such as when an inventory is to be performed. The timer 31 is permanently programmed or can be set via radio if the article tag is in active operating mode P.

The operating state S is characterized by minimizing the energy consumption of the article tag. The controller 24 is located z. B. by reducing the clock frequency and deactivation of various functional blocks in a power saving mode. The UWB receiver 20 is completely switched off. Only the watchdog 21 and the motion sensor 30 be powered. In this way, the power consumption of the article tag can be reduced to the order of less than 10 μA.

Represents the motion sensor 30 a movement fixed or is the timer 31 triggered, this is done by the watchdog 21 registered and the controller 24 from its energy-saving mode in a second operating state P retrieved. Thus, the article tag is available for position determination. The determination of the position of the activated article tags can then be carried out in the same way by triangulation with the aid of measuring stations located in the vicinity of known position, as in the position determination of the portable measuring stations by the stationary measuring stations.

at two-dimensional positioning of the article tag becomes one Position defined as true if the gradual truth value is at least reaches the value of "3". The three-dimensional Position of the article tag can be considered "true" when the gradual truth value has at least the value of "4".

Indeed a reversal of the method is advantageous to the available transmission channel not with a lot of superfluous Flooding trinangulations. In this case collects the article tag in a further embodiment of the invention first of all activating information related to his Positioning can serve and sets this information at the appropriate time to a measuring station.

In an advantageous embodiment of the invention, the measuring stations receive the end of the initialization process successively by the base station 10 a synchronization signal for their watches 46 , In this case, now the known signal transit times between base station 10 and the measuring stations 121 - 128 taken into account so that it is ensured that all system clocks 46 in the measuring stations run at least until the next initialization process equal to the time resolution in the location.

This will, as in 6 , clarifies, allows a time schedule that requires only relatively low demands on the organizational effort. For example, the base station sends 10 via the stationary measuring station 112 to the portable measuring station 123 at time t ₁ a block 91 that's a preamble 910 to synchronize the receiver with a transmitter, a destination address 911 , a sender address 912 , a data block 913 and a CRC character 914 consists. The data block 913 contains the system time of the base station 10 , around the running times of the base station 10 to the portable measuring station 123 was corrected.

After processing the information in the portable measuring station 123 becomes a receipt at time t ₃ 92 sent out in the data block 923 contains the received system time together with a presentation for the time difference t ₃ -t ₁ . This time difference is with the system clock 46 the measuring station determined. The acknowledgment signal is sent back via the stationary measuring station 112 to the base station 10 forwarded.

Will in an embodiment after 4 provided that the article tag 135 has been activated at the time t ₀ by initiating a movement from the state S to the operating state P, the article tag receives the data traffic between the measuring stations from a time after t ₀ 111 to 114 and 121 to 128 in the transmission of time information. In the day 135 become the addresses of the received measuring stations 111 to 114 respectively. 121 to 128 and in the data block 913 respectively. 923 stored time information stored.

Would the article tag 135 at the same distance to the measuring stations 121 to 124 If the data traffic can be received, the received time information would differ exactly by the times t ₁ , t ₉ ... with which the base station 10 the individual measuring stations 121 to 124 has addressed. If the article tag is at different distances from the measuring stations, runtime-related differences arise with the system clock 26 can be determined in the article tag.

A position determination based on that of the measuring stations 111 to 114 and 121 to 128 received time information and with your own system clock 26 ascertained time shifts in the article tag does not appear appropriate because of the computational effort. It is therefore advantageous to bundle this information in a dedicated time slot of a nearby measuring station 111 to 114 and 121 to 128 for forwarding to the base station 10 to hand over

For example, between the time intervals t ₄ -t ₁ or t ₁₂ -t ₉ , in which an exchange of time information between the base station and the measuring stations is provided, there are time intervals t ₈ -t ₅ for the communication between the article tags 130 and the measuring stations are reserved. In the simplest case, each article tag is assigned a time slot by a programming operation. Based on the system times received, the article tag recognizes the relevant time slot and sends a block 81 for example, the measuring station that can be received with the best signal quality. In the block 81 is a data block containing the addresses of the received measuring stations with the respective received time information and the relative times of the reception, which were measured with the own system clock contains.

at The distribution of timeslots should be noted that the article tag due to the article-tag unknown signal delay does not have the exact system time. Between the usable time slots So safety distances are to be inserted, the correspond to the maximum signal propagation times.

Corresponding the inventive method are for a spatial location at least four measuring stations, for Avoid ambiguity more than five measuring stations to recieve. For example, if more than five measuring stations are received, can make a selection based on the signal quality become.

The evaluation of the block 81 through the base station 10 For the purpose of determining the location of the article tag, in turn, as already described, based on the method according to the invention, by determining gradual truth values

1

real area

2

virtual area

3

reflector

4

absorber

5

dots

10

base station

11

Firmly installed measuring stations

12

local Variable Observed

13

Article tag

20

UWB Receiver of the article tag

21

Watchdog of the article tag

22

Power Management

23

Power Supply

24

controller of the article tag

25

Storage of the article tag

26

system clock of the article tag

27

antenna

30

motion sensor

31

timer

40

UWB Receiver of the portable measuring station

44

controller the portable measuring station

45

Storage the portable measuring station

46

system clock the portable measuring station

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• US 2006/0163349 [0003]
• - US 6959862 [0004]
• US 7075476 [0005]
• US 6489893 [0005]
• US 4656463 [0006]
• US 2003/0036374 [0006]

Claims (26)

Electronic article location by measuring the signal transit time between measuring stations and an article tag attached to the article and determining the coordinates of the article tag by triangulation, characterized in that stationary and portable measuring stations are provided, wherein the number of measuring stations in total at least two greater than the number of coordinates of the article tag to be determined. Electronic article location according to claim 1, characterized characterized in that at least one portable measuring station is intended for determining the coordinates of an article tag. Electronic article location according to claim 1, characterized characterized in that the measuring stations are connected to a base station which is a computer that has a fuzzy logic for evaluation the gradual truth content of performed triangulations replicates. Electronic article location according to claim 1 to 3, characterized in that the article tag comprises a motion sensor, a watchdog and a power management module for switching from a power saving mode to an operating condition for the Sending and receiving information through the article tag contains. Electronic article location according to claim 4, characterized that the article tag is a timer for the switchover from a power saving mode to an operating state for sending and receiving information through the Contains article tag. Electronic article location according to claim 5, characterized characterized in that the timer via a radio link is adjustable Electronic article location according to one of the claims 1 to 6, characterized in that the article tags an optical or acoustic signal generator contains. Electronic article location according to one of the claim 1 to 7, characterized in that the article tag over a detachable mechanical connection associated with the article is. Electronic article location according to claim 1 to 8, characterized in that for determining the signal propagation time pulses be used, these pulses are modulated and carriers of one Information is. Method for electronic article location by Measurement of the signal transit times between measuring stations and one article tag attached to the article and determination of the coordinates of the article tag through triangulation, characterized in that the number of in different combinations of stationary Measuring stations carried out triangulation for determination the position of a portable measuring station larger as three times the number of position coordinates to be determined is. Method for electronic article location by Measurement of the signal transit times between measuring stations and one article tag attached to the article and determination of the coordinates of the article tag through triangulation, characterized in that the number of different combinations of measuring stations carried out triangulations to determine the position an article tag larger than three times the Number of position coordinates to be determined. Method for electronic article location according to Claims 10 and 11, characterized in that the results of the triangulations as gradual truth values in a two- or be entered three-dimensional matrix. Method for electronic article location according to Claim 10 to 12, characterized in that the coordinates the elements of the matrix halftone dots with discrete distances in real space or in the real area correspond to and that the determined coordinates of the article tag are the closest Grid point to be assigned. Method for electronic article location according to Claim 10 to 13, characterized in that the coordinates the elements of the matrix halftone dots with discrete distances in real space or in the real area where the are located to locate items, and that the determined Coordinates of the article tag to the nearest grid point be assigned. Method for electronic article location according to Claims 10 to 14, characterized in that by means of the stationary Measuring stations the positions of the portable measuring stations be determined by evaluating the gradual truth value. Method for electronic article location according to Claims 10 to 15, characterized in that a position as is true if the gradual truth value is at least 50% of the maximum possible truth value. Method for electronic article location according to claims 10 to 16, characterized in that in that the paths recognized by the base station are assigned to paths recognized as true, and signal propagation times are recognized as true. Method for electronic article location according to Claims 10 to 17, characterized in that the clocks in the Measuring stations through the base station in cyclic intervals be synchronized. Method for electronic article location according to Claim 18, characterized in that the receipt of a time signal for the purpose of synchronization by the measuring station is acknowledged and this receipt a timestamp of the received time signal and a timestamp of the outgoing acknowledgment signal. Method for electronic article location according to Claim 10 to 19, characterized in that after activation of the article tag by the signal of a motion sensor or a Timer by the receiver in the article tag of traffic the receivable measuring stations is recorded and address and Time information is stored. Method for electronic article location according to Claims 10 to 20, characterized in that by the article tag the stored address and time information of the measuring stations transmitted on request or in a given time slot to a measuring station. Method for electronic article location according to Claims 10 to 21, characterized in that an acoustic Signal is triggered by the article tag when the article tag after its activation not at least a number of measuring stations can receive that by two greater than the number is the coordinates of the article tag to be determined. Method for electronic article location according to Claims 10 to 22, characterized in that an optical signal is triggered by the article tag when the article tag after its activation not at least a number of measuring stations can receive that by two greater than the number is the coordinates of the article tag to be determined. Method for electronic article location according to Claims 10 to 23, characterized in that the article tag falls back into power saving mode when the motion sensor for a certain time no movement more determines. Method for electronic article location according to Claim 10 to 24, characterized in that the frequency determining the position of the article tag by the motion sensor determined values. Method for electronic article location according to Claim 10 to 24, characterized in that the frequency the position determination of the article tag by the determined coordinates of the article tag is affected.