DE102014217504B4 - Zone based location in a near field search space - Google Patents

Abstract

A system for locating (S) a first signal transmitter (X (n)) in a near-field search space, in particular in an interior or in the immediate vicinity of a vehicle (F), comprising: a plurality of different positions arranged in the search space or to be arranged second signal transmitters (Z (z, m)); one or more signal receivers (RX1, RX2; RX3) located at different locations in the search space area for receiving physical signals received by the first signal transmitter (X (n)) and at least one of the second signal transmitters (Z (z, m) ) come; an evaluation unit (A) having means for evaluating the signals received by the signal receiver or receivers (RX1, RX2, RX3); wherein: the second signal transmitters (Z (z, m)) are configured such that the signals to be transmitted by them each identify the second signal transmitter (X (z, m)) transmitting them; the signal receivers (RX1, RX2 RX3) are each capable of detecting at least one physical quantity of the signal they receive, which is a spatial distance of the respective signal receiver (RX1, RX2, RX3) from the signal transmitter (Z (e.g. , m), X (n)) characterized; and the evaluation unit (A) is configured to: - assign each second signal transmitter (Z (z, m)) to a spatial zone (z) defined in the near field search region, - for each zone (z) from the physical quantities of the signal receiver (s) received signals of the second signal transmitter (Z (z, m)) assigned to this zone (z) to determine at least one reference radio situation for the respective zone (z); To determine a comparison radio situation from the physical size of the signals of the first signal transmitter (X (n)) received by the signal receiver (s); - To determine by comparison of the reference radio situation with the reference radio situations of the zones, that zone (z) in which at least one associated reference radio situation according to a similarity measure has the greatest similarity with the reference radio situation, as a probable location of the first signal transmitter (X (n)) and output ; ...

Description

The present invention relates to a zone-based location system and to a method for locating signal transmitters in a near-field search area, in particular in an interior or the immediate surroundings of a vehicle.

For many people, it is an almost daily experience that especially smaller utensils are not located in the designated location, but must first be searched if you want to use or take them for example. In particular, such items may be keys, purses, cell phones, portable computers, ID cards, eyeglasses, garments, handbags, etc., although there may be an almost infinite number of different commodities that must be searched at least one time or the other. The search for the object is often carried out in a spatially narrow search area (near field), which can be defined in particular by a room, an apartment or a building or even the interior of a vehicle, especially a motor vehicle, or its immediate environment.

Against this background, it is known from the prior art to search for everyday objects to be searched for by means of special positioning systems, the articles of daily use being specially equipped with small additional devices for this purpose. For example, it is known to provide articles of daily use with so-called RFID tags which, with a corresponding electromagnetic activation by a first radio signal, return a second radio signal characteristic of them, by means of which the object provided with the RFID tag is in the near field by means of a suitable search device can be located. In other known solutions, the attachment is capable of responding to certain acoustic signals, such as a gossip, by itself emitting a characteristic sound or light signal that can be used to locate the searcher.

In yet other known solutions, the attachment has a GPS receiver and is thus able to transmit its determined position by a transmitting device, in particular via a mobile network, to a receiving device of a searcher.

In the international patent application WO 2013/090427 A1 A system and method for monitoring and tracking the position of a subject is described, in which the subject to be monitored is provided with a transponder whose position is determined by triangulation between a remote GPS-enabled receiver, such as a corresponding mobile phone. and a satellite or a radio transmitter.

In addition, in the field of technologies for portable communication devices, in particular of so-called "smart devices" such as smartphones and tablet computers, navigation solutions for small spaces, especially closed rooms are known in which in the space area several small transmitter ("beacons") as Signalers are arranged, which send signals at fixed time intervals, which can then be received by the communication device. In this case, the signal transmitters send information for their own identity, from which the communication device with the help of associated location information, which can be made available via the Internet, for example, can close its position in the immediate vicinity of the identified signal generator and based thereon, for example, position-related data from the. Internet can retrieve. An example of such location technology is the "iBeacon" technology from Apple, Inc.

From the US 2011/0148714 A1 and the US 2014/0062792 A1 Methods and systems are known for locating a plurality of signal transmitters in a near-field search area, with which the signal transmitters are identified, a distance of a signal transmitter from a signal receiver is detected and the location of the first signal transmitter is assigned to a spatial zone. In each case, data from characteristic received signals are compared with reference data.

From the DE 10 2012 107 821 A1 there are known a position detecting device and a position determining method for determining the position of a portable device such as a remote control key relative to a vehicle by means of radio wave signals emitted from the portable device and a plurality of control devices provided at different locations of the vehicle. be received.

Against this background, the object of the invention is to further improve the technically supported location of objects in a near field search area, in particular in vehicles or their immediate surroundings.

A solution of this object is achieved according to the teaching of the independent claims by a system according to claim 1 for locating signal transmitters in a near-field search area, a vehicle according to claim 12 with such a location system, a corresponding method according to claim 13, and a computer program product according to claim 14 for carrying out the method.

Various embodiments and development of the invention are the subject of the dependent claims.

A first aspect of the invention relates to a system for locating a first signal transmitter in a near-field search area, in particular in an interior or in the immediate surroundings of a vehicle. In this case, the system has a plurality of second signal transmitters arranged or to be arranged at different positions in the search space region. In addition, the system includes one or more signal receivers located at different locations in the search space area for receiving physical signals originating from the first signal transmitter and at least one of the second signal transmitters. Finally, the system also has an evaluation unit with means for evaluating the signals received by the signal receiver (s). In this case, the second signal transmitters are configured such that the signals to be transmitted by them each identify the second signal transmitter transmitting them. The signal receivers are each capable of detecting at least one physical quantity of the signal they receive, which characterizes a spatial distance of the respective signal receiver from the signal transmitter transmitting the signal. The evaluation unit is configured to assign each second signal transmitter to a spatial zone defined in the near-field search region, for each zone from the physical quantities of the signals received by the signal receiver (s) of the second signal transmitters assigned to this zone to determine at least one reference radio situation for the respective zone physical size of the signals received by the signal receiver (s) of the first signal transmitter to determine a comparison radio situation, and by comparison of the reference radio situation with the reference radio situations of the zones, that zone in which at least one associated reference radio situation according to a similarity measure has the greatest similarity with the reference radio situation, as probable location of the first signal transmitter to determine and output. The evaluation unit is further configured to subject the comparison radio situation and the reference radio situations to be compared to this before the comparison of an offset correction.

A "near-field search space area" or "search space area" within the meaning of the invention means a limited space area, ie a subset of the three-dimensional space, within which to determine the position of an object to be searched, in particular of a (first) signal transmitter to be searched for is. In this case, the search area is limited so narrow that it is limited to a near field whose maximum extent of the spatial resolution of known publicly usable localization systems, in particular GPS or Triangulationsmethoden using cellular mobile radio systems corresponds. In particular, the near-field search area can have a maximum extent of only a few meters, in particular less than 30 m, preferably less than 10 m, in particular less than 2 m.

A "vehicle" in the sense of the invention means any type of vehicle by means of which one or more persons and / or cargo can be transported. In particular, a passenger car (PKW), a truck (HGV), a motorcycle, a bus, a bicycle or a trailer to one of the aforementioned vehicles is a vehicle according to the invention. This is especially true for the train unit and the trailer of a train, for a watercraft or an aircraft, in particular an aircraft.

A "signal transmitter" in the sense of the invention is understood to mean a device which is able to emit a physical signal, in particular an electromagnetic radio signal, an optical signal or an acoustic signal (which may also be an ultrasound signal). In particular, according to the RF / D standard, the Bluetooth standard (in particular its Blue Tooth Low Energy versions, eg BT 4.0) or the aforementioned iBeacon technology, radio transmitters are signal transmitters within the meaning of the invention.

A "signal receiver" within the meaning of the invention accordingly means a device which is capable of transmitting a physical signal emitted by a signal transmitter, in particular an electromagnetic radio signal, an optical signal or an acoustic signal, which may also be an ultrasound signal receive. A signal receiver according to the invention may in particular comprise a signal detection device and a receiver circuit. In this case, the signal detection device is used to detect the physical signal to be received and its conversion into an electrical signal and may in particular comprise an antenna, a photosensitive sensor or an acoustic sensor or a combination thereof. The receiver circuit then serves the further treatment of this electrical signal and can in particular cause amplification, filtering, conversion and / or demodulation of the signal. About the transmitted identification information, the signals are each assigned to a specific signal transmitter.

An "evaluation unit" in the sense of the invention is to be understood as a system component of the location system which is able to process the signals or the information contained therein from one or more signal receivers of the system from the signal transmitters and to determine therefrom location information. In particular, an evaluation unit may be a computer system or microcontroller having at least one microprocessor and a memory device and software stored therein for determining the location information by means of the microprocessor.

For the purposes of the invention, a "physical size of the signal which characterizes a spatial distance of the respective signal receiver from the signal transmitter transmitting signals" means a technically detectable characteristic of the signal received at the signal receiver, which is regular to the spatial distance between the signal transmitter and the signal receiver correlated and so at least rough conclusions on this distance allows. The term "physical quantity" is not limited to terms in the sense of an amplitude of the signal or the like.

A "spatial zone" or "zone" for the purposes of the invention is to be understood as meaning a spatial subarea of the near field search space region, to which at least one second signal transmitter arranged or to be arranged there is assigned. The boundary of a zone does not have to be defined exactly. Rather, the zone may in particular be defined as the immediate environment of a concise object in the near field search space area. In the case of a motor vehicle, this object may, in particular, be a visible part of the vehicle or its equipment.

A "radio situation" in the sense of the invention means a set of measurement results for the said physical quantity of the received signals, which are detected by the signal receivers upon receipt of the respective signals of the first and second signal transmitters. In particular, the set of measurement results may include a measurement result for each pair of a signal transmitter and a signal receiver. A "reference radio situation" is to be understood as meaning a radio situation which contains the measurement results for the second signal transmitters, while a "comparison radio situation" is to be understood as meaning a radio situation which contains the measurement results to or to a corresponding first signal transmitter.

A "similarity measure" in the sense of the invention means a mathematical measure, by means of which a difference or a degree of agreement between two radio situations can be quantified, in particular to a single value characterizing the difference or the match.

For the purposes of the invention, "outputting" of a zone means that information identifying the zone is made available by the location system. In particular, this can be done directly by outputting the information on a man-machine interface, for example a display device or a loudspeaker or signal generator, or by transmitting it to a data memory, an application or another system or provision thereof.

The location system can be used to locate a first signal transmitter to be searched in the near-field search area. On the one hand, possible advantages are that because of the only zone-related position determination, significantly lower requirements are required for the accuracy of the position determination for the first signal transmitter than would be required for an absolute position determination (for example of position coordinates in a reference coordinate system), a comparable search efficiency to reach. Thus, the method can be based on simple technical positioning method whose accuracy is also clear, z. B. one to two orders of magnitude, can be coarser than the size of the objects to be located. In particular, signal strength measurements or signal propagation time measurements for the physical signals may be used to approximate the distance between the signal transmitters and the signal receivers. The signals themselves do not have to contain any information about the positions of the respective signal transmitters and, accordingly, the signal transmitters or objects coupled thereto do not have to be able to know or grasp their spatial position themselves. The signal transmitters can thus be designed very simply and, in particular, need neither be designed for bidirectional communication nor even have a location functionality. Also, the signal receiver need not be sensitive to direction. In particular, advantageously miniaturized signal transmitters (beacons) and receivers can be used, which enables particularly cost-effective solutions with very low space and energy requirements. In addition, the system allows dynamic adaptation to time-varying influences on the signals, for example, when people or objects move into the near-field search space area (or move away) and thus cause variable signal attenuation.

Hereinafter, preferred embodiments of the positioning system and their Further developments are described, which may be combined with each other as well as with the other aspects of the invention described below, unless expressly excluded.

Preferably, the near field search space is through the interior of a vehicle, such as a car, or its immediate, d. H. Surroundings limited to a few meters from the vehicle, defined by a vehicle garage, by a building or by one or more rooms therein.

The first signal transmitter can in particular be coupled to or coupled to a search object to be located. In this case, the search object can be, in particular, an object to be searched for. In the event that the search space area is defined by the interior of a vehicle, its immediate surroundings or a garage or a parking space of the vehicle, the search object may in particular a parking disc, a car key, a pair of glasses, an ice scraper, a safety vest, a first aid kit, a Warning triangle or any other mobile element of the equipment or the loading of the vehicle possibly to be searched for, or else a person or an animal. The coupling of the first signal transmitter to the search object can take place in any desired manner, in particular by means of a mechanical connection, advantageously such that the signal transmitter is located in or on the respective object. In particular, the signal transmitter may already have been integrated into the search object during production. Alternatively, however, he can also be connected with this later or have been. In this way, any objects can be equipped as search objects by means of a signal transmitter and thus use for the search. Also, tagging an object with a signal transmitter is often referred to as tagging.

According to a preferred embodiment, the associated second signal transmitters of at least one zone are configured to transmit the signals to be transmitted by them at intervals at regular time intervals, preferably at a frequency of at least 1 Hz, and the evaluation unit is further configured to provide the reference radio situation for at least to determine one of the zones at least once per time interval. In this way it is possible to implement a regular, in particular quasi-continuous order function, and in the evaluation per time interval, all second signal transmitters can always be taken into account.

According to a development, the interval frequency is so high that it can be assumed during the interval of quasi-static radio conditions (i.e., that the radio channels between transmitters and receivers do not change significantly during the time interval), then the reliability and accuracy of the location can be increased. Especially with regard to changes in the radio conditions due to movement of persons or objects in a vehicle or its exterior, a frequency of 1 Hz or higher is particularly advantageous in view of the associated typical movement speeds.

According to a further development, the evaluation unit is configured to determine the comparison radio situation to be compared with the reference radio situations at a first time interval by combining the comparison radio situation actually detected with the first time interval with the reference radio situation to one or more second time intervals adjacent to the first time interval. Additionally or alternatively, the evaluation unit is configured to determine at least one reference radio situation at a first time interval by combining the reference radio situation of the zone actually detected with the first time interval with the reference radio situation to one or more second time intervals adjacent to the first time interval. In particular, the combining by weighted averaging over the individual comparison radio situations or reference radio situations can take place at the time intervals considered in the respective summary. By combining several temporally adjacent radio situations, the robustness of the location determination can be increased since extremely briefly occurring signal disturbances, which occur for example only during one or less of the intervals taken into account in the summary, are suppressed.

According to a further preferred embodiment, the evaluation unit is configured such that if there is a plurality of second signal transmitters to a zone, the reference radio situation for this zone is determined by combining the measurement results for the plurality of second signal transmitters. In this case, this combination can be carried out in particular by weighted averaging over the measurement results or by selecting only a subset of measurement results for a single one of the second signal transmitters in this zone as a reference radio situation for the zone. Alternatively, the evaluation unit may be further configured to instead bill the equivalence measures for the second signal transmitters associated with the zone into a single value for the equivalence measure for that zone. In this way, each of the robustness of the location for this zone can be increased, because it no longer depends solely or no longer on the possibly disturbed or over-attenuated signal of a single second signal transmitter for the zone.

According to a further preferred embodiment, the evaluation unit is further configured to subject the comparison radio situation and the reference radio situations to be compared to an offset correction before comparison, in particular by matching the average values over all individual values of the physical variable for the respective radio situation. The offset correction improves the comparability of the signals and thus the positioning accuracy. This can be advantageous in particular if the signal strengths for the signals emitted by the individual signal transmitters differ significantly. This may be the case, for example, when the first signal transmitter transmits significantly weaker than the second signal transmitter permanently arranged in the near-field search space region (for example when a second signal transmitter is supplied via a network or a car battery, while the first signal transmitter is connected to a device to be located mobile tag is formed and powered only by a small battery).

According to yet another preferred embodiment, the second signal transmitters are configured such that the signals to be transmitted by them each contain at least one data packet via which the transmitting signal transmitter is identifiable. In this way, a simple and unambiguous identification, in particular via an identifier contained in the data packet for the signal transmitter can be achieved.

In accordance with yet another preferred embodiment, the physical quantity to be detected by the respective signal receiver represents a signal to be received, a received signal strength, in particular a receive power of the received signal, or a delay of the signal between the signal transmitter and the signal receiver Determine signal easily, so that in this way can be deduced efficiently and simply conclusions on the at least approximate distance between signal transmitters signal receiver.

• • ein oder mehrere bestimmte Sitzplätze;
• • Staufach
• • Kofferraum
• • Fahrzeuginnenraum als Ganzes
• • Fahrzeugaußenraum als Ganzes
• • Annäherungszonen im Fahrzeugaußenraum an einer Fahrzeugseite, im Fahrzeugvorfeld oder an der Rückseite des Fahrzeugs.

According to yet another preferred embodiment, the system is provided for a motor vehicle, and the evaluation unit is further configured to define one or more of the following spatial regions of the near field search space as spatial zones for the assignment of the second signal transmitters:

• • one or more specific seats;
• • storage compartment
• • trunk
• • Vehicle interior as a whole
• • Vehicle exterior as a whole
• • Approach zones in the vehicle exterior on one side of the vehicle, in the vehicle apron or at the rear of the vehicle.

These are in each case areas of space in or around the vehicle, which on the one hand are easily recognizable or identifiable by the seeker and, on the other hand, represent frequent locations for the search for objects. For example, the location system could locate an object provided with a first signal transmitter (tagging) in the trunk of the vehicle and give the seeker an appropriate indication of the "trunk" zone, so that the searched item can be found directly in the trunk without further search ,

Particularly preferred locations for the arrangement of the signal receiver or receivers in the vehicle are accordingly the roof or a position at the top in the vehicle interior, the trunk, the engine compartment, the glove box, storage compartments at various points of the vehicle, especially in the side doors, the room under the seats, in particular the front seats, the center console, or even the spare wheel well, if available.

According to yet another preferred embodiment, the evaluation unit is further configured to also determine and output a probability for the zone determined as the probable location of the first signal transmitter that the first signal transmitter is actually located in the particular zone. This can have the advantage that, with a high probability, the search can be concentrated solely on the indicated zone, while with only a small probability the searcher is signaled that the first signal transmitter, or an object provided with it, is also with significant probability another zone, in particular a zone adjacent to the particular zone.

In accordance with yet another preferred embodiment, the evaluation unit is further configured such that the comparison or reference radio situations are respectively determined by a set of measured values for the physical quantities of the received signals from each of the first and second signal transmitters respectively detected by the individual signal receivers , In this case, the set of measured values can be stored in particular in the form of a table or a corresponding data structure, and for each transmitter / receiver pair contain the corresponding detected value for the physical size of the respective received signal. In this way, the radio situations be easily and efficiently quantified, if necessary further processed and compared with each other.

In accordance with yet another preferred embodiment, the system is also adapted to receive signals from a plurality of different first signal transmitters via the signal receivers and to evaluate them via the evaluation unit, thereby identifying the individual first signal transmitters on the basis of the signals (5) to be transmitted by them and for each of them first signal transmitter to issue a presumed abode zone. Preferably, the signals of each first signal transmitter, like those of the second signal transmitter, also contain an identification which identifies them, so that different first signal transmitters can be distinguished easily. In this way, it is possible to easily distinguish a plurality of first signal transmitters located in the near-field search area in their simultaneous location.

In accordance with yet another preferred embodiment, the evaluation unit is further configured to store the zone determined as the probable location of the first signal transmitter in the form of corresponding data in a memory, transfer it to an application, display or signal it on a man-machine interface, or via a data transmission link to a remote station to transfer.

A second aspect of the invention relates to a vehicle, in particular a motor vehicle, which is equipped with a system for locating according to the first aspect of the invention.

A third aspect of the invention relates to a method for locating a first signal transmitter in a near-field search area, in particular in an interior space or in the immediate vicinity of a vehicle, in particular by means of the location system according to the first aspect of the invention, comprising the steps:
Receiving, by means of at least one signal receiver, physical signals originating from the first signal transmitter and at least one second signal transmitter, the second signal transmitters being located at different positions in the search space region and configured so that the signals to be transmitted by them are each to the signal transmitter transmitting them each being able to detect at least one physical quantity of the signal they receive characterizing a spatial distance of the respective signal receiver from the signal transmitter transmitting the signal;
Associating each second signal transmitter with a spatial zone defined in the near field search area;
Determining, for each zone, at least one respectively associated reference radio situation from the physical quantities of the signals received by the signal receiver (s) of the second signal transmitter assigned to this zone;
Determining a comparison radio situation from the physical magnitude of the signals of the first signal transmitter received by the signal receiver (s); and
Determining and outputting of that zone as a probable location of the first signal transmitter, in which at least one associated reference radio situation in accordance with a similarity measure has the greatest similarity with the reference radio situation, by comparing the reference radio situation with the reference radio situations of the zones.

According to a preferred embodiment, the assignment of the second signal transmitter to the individual zones can be done in advance of the actual location method, z. B. frame of an initialization. This can occur, for example, when the system is first started up or after a reset of the system. Use cases for this are, for example, an initialization of an integrated in a vehicle positioning system (with installed stationary in the vehicle second signal transmitters and signal receivers) before its delivery or reinitialization of the system after the same to another place (such as another room in a building) or after the addition or removal of second signal transmitters and / or signal receivers.

Alternatively or additionally, in a further preferred embodiment, the assignment can also take place dynamically during the operation of the positioning system, in particular also in the context of the positioning method itself. In this case, first the signals of the second signal transmitters are received, by means of which they can be identified by the evaluation unit, and based thereon only a first or reassignment of the second signal transmitters to zones (in particular of the evaluation unit) is carried out. For this purpose, the second signal transmitters can preferably also have information about their absolute (with respect to a defined coordinate system) or relative (with respect to a reference point, eg of an object in the vehicle) spatial position in the near-field search region, in particular as the part of or in addition to send the identification information, in their signals. In another variant, this position information (for example, in the rear right) is otherwise provided to the evaluation unit, for. B. by reading from a memory or by manual input.

Finally, a fourth aspect of the invention relates to a computer program product containing instructions which, when executed on one or more processors of a computer program product Positioning system according to the first aspect of this invention cause it to carry out the method according to the third aspect of the invention. In particular, the computer program product may be in the form of a data carrier on which one or more programs for executing the method are stored. This is preferably a data carrier, such as a CD, a DVD or a flash memory module. This may be particularly advantageous if the computer program product as such is to be traded or used by the user of the location system itself to program it. Alternatively or additionally, the computer program product can also be present as a file on a data processing unit, in particular on a server, and can be loaded into the positioning system via a data connection (eg via download via the Internet or a dedicated data connection).

Preferred uses of the location system according to the first aspect of the invention or the location method according to the third aspect of the invention will be described below, which may be combined with each other as well as with the previously described aspects of the invention, unless expressly excluded.

According to a preferred use, the location system may be used to identify, locate, or inspect items in a rental or rental vehicle or in a car-sharing vehicle.

According to a further preferred use, the positioning system can be used in vehicles provided or used for the transport of cargo for the rapid or simple automated inventory or cataloging of a load, the elements of which are each provided with a signal transmitter.

Finally, the locating system according to a further preferred use can also be advantageously used to the basic equipment of a vehicle, in particular the statutory basic equipment (first aid kit, warning triangle, warning vests and the like), but preferably also an even beyond equipment (especially replacement bulbs, flashlights, warning lights , Jack, tool, mobile phone, gloves, blanket and the like) for completeness. In a variant of this, a use of checking the completeness of the equipment of a first-aid kit (scissors, compression, pavement, etc.) as such can advantageously be effected by means of the locating system, the individual elements of this equipment each being provided (preferably ex works) with a signal transmitter.

The statements made above in each case for the use of the locating system apply equally to the use of the method according to the invention.

Further advantages, features and possible applications of the present invention will become apparent from the following detailed description taken in conjunction with the figures.

It shows

1 schematically a location system according to a preferred embodiment of the invention, or a vehicle equipped therewith, wherein the search space area is given by the vehicle and its immediate vicinity;

2 According to a preferred embodiment of the invention, a table for storing data of the signal transmitters in the evaluation unit or an associated memory;

3 according to a preferred embodiment of the invention, a "look-up" table for detecting a radio situation on the basis of received powers at the signal receivers at a measuring time;

4 according to a preferred embodiment of the invention, a table for storing and / or outputting location results using confidence information for different zones; and

5 a flowchart illustrating a preferred embodiment of the method according to the invention.

1 1 shows a location system S according to a preferred embodiment of the invention or a vehicle F equipped therewith. The location system S is suitable and intended to have one or more (N) first signal transmitters X (n), where n = 1, 2, ... Locate N in a search space area given by the vehicle or its immediate vicinity. For this purpose, the positioning system S has a plurality of second signal transmitters Z (z, m), which serve as reference transmitters for detecting a reference radio situation. The search space region is divided into a plurality of spatial zones z (z = 0 to 7 in the example) and the second signal transmitters Z (z, m) are each assigned to one of these zones, the index m indicating the second signal transmitters of the associated zone z. Accordingly, for example, the in 1 in zone 3 arranged second signal transmitter with Z (3, 1), since he himself is located in zone 3 and has the current station number 1 within this zone. In zone 1, on the other hand, two reference transmitters Z (1, 1) and Z (1, 2) are arranged. While the zones z = 0 to 5 are defined inside the vehicle, the zones with z = 6 and / or 7 cover the left or right temporal near field outside of the vehicle as viewed in the direction of travel. As radio technology in particular the BT 4.0 (BLE) based iBeacon technology can be used.

Furthermore, the exemplary order system S has three signal receivers RX1, RX2 and RX3 arranged at different locations of the vehicle, which are respectively suitable and provided, the signals to be emitted by the first and second signal transmitters X (n) and Z (m, z) to receive and forward to an evaluation unit A. The signals contain information, in particular data packets, via which the respective signal transmitters emitting the signals can be identified.

2 shows an exemplary table for storing data of the signal transmitters in the evaluation unit or an associated memory. In this case, an identification of the respective signal transmitter (Beacon ID) is specified in the first column, which corresponds to the identification information contained in the signals or corresponds to this. In the middle column, a logical designation of the respective signal transmitter is given, as already described above. This logical designation can preferably be defined dynamically by the evaluation unit A or also programmed manually. Finally, the function of the respective signal transmitter as the reference transmitter or tag transmitter (first signal transmitter) and a designation of the respective zone for the reference transmitter are indicated in the third column.

In 3 is exemplified a reference radio situation at a given time of measurement tabulated. In this case, the reference radio situation for all associated reference transmitters Z (z, m) is quantified by their respective received signal powers (eg measured in decibels "dB") via the identity information provided in the signals to the signal receivers RX1, RX2 and RX3. This results in a total of the in 3 shown data the reference radio situation at the given time. In the same way, the comparison radio situation can be detected for each of the first signal transmitters X (n), which for each first signal transmitter X (n) of a row in a table analogous to 3 equivalent.

In 4 is an exemplary table for storing and / or outputting location results for the first signal transmitter X (n = 1) using confidence information P (n = 1, z) shown for different zones z. In this case, the confidence in the second column for each zone z denotes the specific probability that the first signal transmitter X (1) will find itself in the corresponding zone. In the concrete example 4 Accordingly, a probability of 88% has been determined for the signal transmitter X (1), or a sought-after object coupled thereto, to be in zone 1, while the probability that it is in zone 5 was determined to be only 3% , Alternatively, for example, the output may be limited to specifying only the zone for which the highest confidence was determined.

5 Finally, FIG. 3 shows a flowchart for illustrating a preferred embodiment of the method according to the invention for locating one or more first signal transmitters X (n), which is subsequently described using the exemplary embodiments according to FIG 1 to 4 is described.

In this case, in a step S1, in particular as part of an initialization of the order system S, an assignment of each second signal transmitter Z (z, m) is made to a defined zone z. The first and second signal transmitters regularly emit signals at intervals, so that in each transmission interval each of the signal transmitters emits its corresponding signal at least once, which also identifies it with respect to the evaluation unit A. Alternatively, step S1 can also take place only after the steps S2 or S3 described below.

In a further step S2, the signals emitted by the second signal transmitters Z (z, m) and optionally one or more first signal transmitters X (n) within the same transmission interval are received by the signal receivers RX1, RX2 and RX3.

In this case, the received signal strength, in particular the received power, for each of the signals is detected by the signal receivers RX1, RX2 and RX3 by measurement in a, preferably parallel to S2 running, step S3.

In a step S4, from the received signals of the second signal transmitters Z (z, m), a reference radio situation is preferably determined for each, but at least for a subset of the zones. The reference radio situation can, in particular according to the in 3 illustrated manner based on received signal values are determined. In a preferred refinement, the results of several measurements from different, temporally adjacent intervals per signal transmitter / signal receiver pair are compared with one another for a received signal value per second signal transmitter Z (z, m) and signal receiver RX1 to RX3, in particular by forming a sliding, weighted average for each received signal value over the considered intervals.

In a step S5, preferably at the same time, a comparison radio situation is determined in the same way for each of the available first signal transmitters X (n) from the received signals of the respective first signal transmitter X (n).

In a still further step S6, a comparison of the reference radio situations with the reference radio situation (s) takes place, which preferably takes place in pairs between a respective reference radio situation and a comparison radio situation, which preferably are still each preceded by offsets. In the comparison, a similarity measure is determined for each of these pairs. In particular, the root mean square error (root-mean-square-error) of the received measured values for the respectively compared received signal values of the associated first and second signal transmitters can be selected as the measure of similarity. On this basis, for each location to be located first signal transmitter X (n) that zone z _{0 is} determined in which at least one associated reference radio situation according to the similarity measure the greatest similarity with the reference radio situation for this first signal transmitter, ie here the smallest deviation thereof. As far as several second signal transmitters are assigned to the same zone z, as in 2 for zone 1, the equivalence measures for the second signal transmitters associated with the zone can be offset against each other to a single value for the equivalence measure for this zone beforehand, preferably again by weighted averaging. On the basis of the value of the similarity measure for the zone thus determined, a probability value P (n, z0) can then also be determined for the stay of the associated first signal transmitter in this zone Z and output in a step S7.

The outputting in step 7 can take place, in particular, by providing the information about the specific zone (for example, zone number) to an application in a central control device of the vehicle F, which can also be part of the evaluation unit A itself. The zone can also be communicated directly to the driver or other persons via a man-machine interface.

The method can preferably be implemented by means of a corresponding control program, which can run in particular on at least one processor of the evaluation unit A.

LIST OF REFERENCE NUMBERS

• A

  evaluation

  F

  vehicle

  S

  tracking system

  RX1-3

  signal receiver

  X (n)

  nth first signal transmitter

  Z (z, m)

  mth second signal transmitter (reference transmitter) in zone z

Claims (14)

A system for locating (S) a first signal transmitter (X (n)) in a near-field search space, in particular in an interior or in the immediate vicinity of a vehicle (F), comprising: a plurality of different positions arranged in the search space or to be arranged second signal transmitters (Z (z, m)); one or more signal receivers (RX1, RX2; RX3) located at different locations in the search space area for receiving physical signals received by the first signal transmitter (X (n)) and at least one of the second signal transmitters (Z (z, m) ) come; an evaluation unit (A) having means for evaluating the signals received by the signal receiver or receivers (RX1, RX2, RX3); wherein: the second signal transmitters (Z (z, m)) are configured such that the signals to be transmitted by them each identify the second signal transmitter (X (z, m)) transmitting them; the signal receivers (RX1, RX2 RX3) are each capable of detecting at least one physical quantity of the signal they receive, which is a spatial distance of the respective signal receiver (RX1, RX2, RX3) from the signal transmitter (Z (e.g. , m), X (n)) characterized; and the evaluation unit (A) is configured to: - assign each second signal transmitter (Z (z, m)) to a spatial zone (z) defined in the near field search region, - for each zone (z) from the physical quantities of the signal receiver (s) received signals of the second signal transmitter (Z (z, m)) assigned to this zone (z) to determine at least one reference radio situation for the respective zone (z); To determine a comparison radio situation from the physical size of the signals of the first signal transmitter (X (n)) received by the signal receiver (s); - By comparison of the reference radio situation with the reference radio situations of the zones, that zone (z) in which at least one associated reference radio situation according to a similarity measure has the greatest similarity with the reference radio situation, as the probable location of the first Signal transmitter (X (n)) to determine and output; and - wherein the evaluation unit (A) is further configured to subject the comparison radio situation and the reference radio situations to be compared with it before the comparison of an offset correction. The system of claim 1, wherein the associated second signal transmitters (Z (z, m)) of at least one zone (z) are configured to transmit the signals to be transmitted by them at regular time intervals, preferably at a frequency of at least 1 Hz; and the evaluation unit (A) is further configured to determine the reference radio situation for at least one of the zones (z) at least once per time interval. The system of claim 2, wherein the evaluation unit (A) is further configured: to determine the comparison radio situation to be compared with the reference radio situations at a first time interval by combining the comparison radio situation actually detected with the first time interval with the reference radio position or situations to one or more second time intervals adjacent to the first time interval; or determining at least one reference radio situation at a first time interval by combining the reference radio situation of the zone (z) actually recorded with the first time interval with the reference radio situation (s) to one or more second time intervals adjacent to the first time interval; or both. The system according to claim 3, wherein the summarizing takes place by weighted averaging over the individual comparison radio situations or reference radio situations at the time intervals considered in the respective summary. System according to one of the preceding claims, wherein the evaluation unit (A) is further configured such that, if there is a plurality of second signal transmitters (Z (z, m)) to a zone (z), The reference radio situation for this zone (z) is determined by combining the measurement results for the plurality of second signal transmitters (Z (z, m)), or - the equivalence measures for the zone (z) associated second signal transmitter (Z (z, m)) with each other to a single value for the equivalence measure for this zone (z) is calculated. System according to one of the preceding claims, wherein the second signal transmitters (Z (z, m)) are configured such that the signals to be transmitted by them each comprise at least one data packet via which the transmitting second signal transmitter (Z (z, m)) is identifiable. System according to one of the preceding claims, wherein the physical quantity to be detected by the respective signal receiver (RX1, RX2, RX3) of a signal to be received by it, a received signal strength, in particular a received power of the received signal, or a propagation time of the signal between signal transmitters (Z ( z, m), X (n)) and signal receiver (RX1, RX2, RX3). System according to one of the preceding claims, wherein the system is provided for a motor vehicle (F) and the evaluation unit (A) is further configured to use one or more of the following space regions of the near field search space as spatial zones (z) for the assignment of the second Signal transmitter (Z (z, m)) to define: • one or more specific seats; • storage compartment • trunk • Vehicle interior as a whole • Vehicle exterior as a whole • approach zones in the vehicle exterior on one side of the vehicle, in the apron or at the rear of the vehicle; The system according to one of the preceding claims, wherein the evaluation unit (A) is further configured to also determine and output a probability of the zone (z) determined to be the presumed location of the first signal transmitter (X (n)) Signal transmitter (X (n)) is actually located in the particular zone (z). A system according to any one of the preceding claims, wherein the evaluation unit (A) is further configured such that the reference radio situations are each determined by a set of measurements for the physical quantities of each of the individual signal receivers (RX1, RX2, RX3) received signals from each of the first and second signal transmitters (X (n), Z (z, m)) is determined. A system according to any one of the preceding claims, wherein the system is further adapted to receive signals from a plurality of different first signal transmitters (X (n)) via the signal receivers (RX1, RX2, RX3) and to evaluate them via the evaluation unit (A) and the individual first ones Signal transmitter (X (n)) to identify each based on the signals to be sent by them and for each of the first signal transmitter (X (n)) to output a probable location zone (z). Vehicle (F), in particular a motor vehicle, which is equipped with a system for locating (S) according to one of the preceding claims. Method for locating a first signal transmitter (X (n)) in a near-field search space, in particular in an interior or in the immediate surroundings of a vehicle, comprising the steps of: receiving, by means of at least one signal receiver (RX1, RX2, RX3), physical Signals originating from the first signal transmitter (X (n)) and at least one second signal transmitter (Z (z, m)), the second signal transmitters (Z (z, m)) being arranged and configured at different positions in the search space region in that the signals to be transmitted by them each identify the second signal transmitter Z (z, m) transmitting them, and wherein the signal receivers (RX1, RX2, RX3) are each capable of detecting at least one physical quantity of the signal received by them which characterizes a spatial distance of the respective signal receiver (RX1, RX2, RX3) from the signal transmitter (X (n), Z (z, m)) transmitting the signal; Associating each second signal transmitter (Z (z, m)) with a spatial zone (z) defined in the near field search region; Determining, for each zone (z), at least one respectively associated reference radio situation from the physical quantities of the signals received by the signal receiver (s) (RX1, RX2, RX3) of the second signal transmitter (Z (z, m) assigned to this zone (z) ); Determining a comparison radio situation from the physical quantity of the signals of the first signal transmitter (X (n)) received by the signal receiver (s) (RX1, RX2, RX3); and determining and outputting that zone (z) as the presumed location of the first signal transmitter (X (n)) in which at least one associated reference radio situation has the greatest similarity to the reference radio situation in accordance with a similarity measure, by comparing the reference radio situation with the reference radio situations of the zones (e.g. ), wherein the comparison radio situation and the reference radio situations to be compared are subjected to an offset correction before the comparison. Computer program product containing instructions which, when executed on one or more processors of a location system according to any one of claims 1 to 12, cause it to carry out the method according to claim 13.

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