Method and system for determining a position of an object by means of signal deflection

Abstract

The present invention relates to a method for determining a position of an object (15) by means of signal deflection, in particular signal reflection, to a computing unit and a computer program for carrying out said method, and to a transmitting / receiving system. A signal emitted by a first transmitting / receiving unit (21b, 20) into a spatial region (100) is deflected by the object (15) in the spatial region (100) and is received by a second transmitting / receiving unit (20, 21b). A reference signal emitted by a third transmitting / receiving unit (21a) to the second transmitting / receiving unit (20, 21b), a position indication of the first transmitting / receiving unit (21b, 20) and a position indication of the third transmitting / receiving unit (21a) are received by the second transmitting / receiving unit (20, 21b), and a position of the at least one object (10) is determined by the second transmitting / receiving unit (20, 21b) on the basis of the deflected, in particular reflected, emitted signal, the reference signal, the position indication of the first transmitting / receiving unit (21b, 20) and the position indication of the third transmitting / receiving unit (21a).

Description

[0001] Description

[0002] title

[0003] Method and system for determining the position of an object using signal deflection

[0004] The present invention relates to a method for determining a position of an object by means of signal deflection, in particular signal reflection, and a computer program for carrying out the method, as well as a transmitting / receiving unit and a transmitting / receiving system.

[0005] Background of the invention

[0006] To increase safety, efficiency, and comfort in road traffic, cooperative intelligent transport systems are increasingly being used. These systems enable communication from vehicle to vehicle (V2V), from vehicle to roadside infrastructure (V2I), and from vehicle to other persons (V2P). Collectively, the wireless data exchange between the various actors is referred to as cooperative V2X communication. Roadside units (RSUs) can be used to provide V2I communication. These units can be set up, for example, at intersections, motorway entrances, or other traffic junctions. These can contain cameras, radar and / or lidar sensors, and the like, and exchange information with vehicles in their vicinity using a specified message format.For example, the RSUs can send information about the status of lighting systems and road conditions to passing vehicles and receive information from them about their position, speed, etc. However, this type of communication excludes road users and objects that do not have the appropriate communication interfaces (e.g. older vehicles, bicycles, etc.). One way to determine the position of non-networked objects, for example, is to evaluate deflected, particularly reflected, signals such as radar signals. This can be done using special signals from radar units that can be attached to RSLIs and vehicles, for example, or communication signals that are sent in a defined frequency range by vehicles, RSLIs, or mobile radio base stations (e.g. via Dedicated Short Range Communication (DSRC) or cellular V2X (C-V2X)).

[0007] However, in order to determine the position of an object using a signal deflected, particularly a reflected, from the object, the transmitter and receiver must be synchronized in time. To do this, a receiver typically receives a transmitted signal both via a line of sight (LoS) and as an echo signal reflected from the object. Based on the time difference between the direct and deflected, particularly reflected, signals, the distance between the transmitter and receiver, and the angle at which the echo signal hits the receiver, the distance between the receiver and the object can be determined. If there is no line of sight between the transmitter and receiver, this leads to significant losses in positioning accuracy.

[0008] Disclosure of the invention

[0009] According to the invention, a method for determining the position of an object by means of signal deflection, in particular signal reflection, and a computer program for implementing the method, as well as a transmitting / receiving unit and a transmitting / receiving system having the features of the independent patent claims, are proposed. Advantageous embodiments are the subject of the subclaims and the following description. The invention enables precise determination of the position of an object in a reflection path of a transmitted signal without a line of sight between the transmitter and receiver being or having to be. For this purpose, a reference signal is sent from a further transmitting / receiving unit to the receiver, wherein the further transmitting / receiving unit has a line of sight or a (time-synchronous) communication connection with the receiver.

[0010] In detail, a signal is transmitted from a first transmitting / receiving unit into a spatial area and the transmitted signal is deflected, in particular reflected, by an object in the spatial area and received by a second transmitting / receiving unit.

[0011] The first transmitting / receiving unit can be, for example, a stationary transmitting / receiving unit, and the second transmitting / receiving unit can be a mobile transmitting / receiving unit. The stationary transmitting / receiving unit can be, for example, an RSU or a mobile radio base station. The mobile transmitting / receiving unit can be, for example, a vehicle. Other stationary and mobile transmitting / receiving units are also possible.

[0012] Alternatively, the first transmitting / receiving unit may be a mobile transmitting / receiving unit and the second transmitting / receiving unit may be a stationary transmitting / receiving unit.

[0013] The spatial area can be, for example, a road intersection, an entrance or exit to a road or another traffic area.

[0014] The object can be, for example, another road user, a person or an object.

[0015] Furthermore, a reference signal is sent from a third transmitting / receiving unit to the second transmitting / receiving unit, and a position indication of the first transmitting / receiving unit (ie an indication or information about the position of the first transmitting / receiving unit) and a position indication of the third transmitting / receiving unit are received by the second transmitting / receiving unit.

[0016] The transmitted signal and / or the reference signal can be, for example, a sensor signal, such as a radar or lidar signal, or a communication signal, such as a cellular signal or a DSRC signal. In the latter case, a physical layer of the communication signal can be accessed to treat it like a sensor signal.

[0017] The third transmitting / receiving unit can in particular be a stationary transmitting / receiving unit which has a line of sight or a (time-synchronous) communication connection with the first transmitting / receiving unit.

[0018] In this way, the third transmitting / receiving unit can provide a signal that has a temporal reference to the signal transmitted by the first transmitting / receiving unit. In conjunction with the received position information from the first and third transmitting / receiving units, this enables the second transmitting / receiving unit to determine a virtual line-of-sight signal to the first transmitting / receiving unit, as explained in more detail below. Within the scope of this disclosure, a "line-of-sight signal" is understood to mean a signal that is transmitted directly and without reflections.

[0019] Based on the deflected, in particular reflected, transmitted signal, the reference signal, the position information of the first transmitting / receiving unit and the position information of the third transmitting / receiving unit, a position of the at least one object is then determined by the second transmitting / receiving unit.

[0020] The terms "first," "second," and "third" serve to differentiate the individual transmitting / receiving units from one another and do not limit them to three. A plurality of transmitting / receiving units, each transmitting and receiving a plurality of signals, may be present. The following describes embodiments of the invention in which the first transmitting / receiving unit is a stationary transmitting / receiving unit and the second transmitting / receiving unit is a mobile transmitting / receiving unit. Embodiments in which the first transmitting / receiving unit is a mobile transmitting / receiving unit and the second transmitting / receiving unit is a stationary transmitting / receiving unit are subsequently described. The third transmitting / receiving unit is a stationary transmitting / receiving unit in both cases.

[0021] According to one embodiment, the first transmitting / receiving unit is a first stationary transmitting / receiving unit, the second transmitting / receiving unit is a mobile transmitting / receiving unit, and the third transmitting / receiving unit is a second stationary transmitting / receiving unit that has a line of sight with the mobile transmitting / receiving unit. This means that the first stationary transmitting / receiving unit transmits the signal into the spatial area, and the mobile transmitting / receiving unit receives the signal deflected, in particular reflected, by the object. In this case, the reference signal can be a line-of-sight signal that is transmitted from the second stationary transmitting / receiving unit to the mobile transmitting / receiving unit at a specific temporal relationship to the transmitted signal of the first stationary transmitting / receiving unit.In other words, the mobile transmitting / receiving unit can receive a signal (the reference signal) on a direct path from the second stationary transmitting / receiving unit, which was transmitted at a specific temporal relationship to the deflected, in particular reflected, signal. In particular, the line-of-sight signal can be of the same signal type (sensor signal or communication signal) as the signal transmitted by the mobile transmitting / receiving unit and deflected, in particular reflected, at the object. "At a specific temporal relationship" means that the interval between the points in time is known. It can also be zero, i.e., the processes can occur simultaneously. However, it can also be greater than zero, for example, to avoid interaction between the two signals. However, the interval should not be so large that the environment or position of the mobile transmitting / receiving unit changes significantly.According to one embodiment, before the first stationary transmitting / receiving unit transmits the signal into the spatial area, a transmission time of the signal to be transmitted, sent from the first stationary transmitting / receiving unit to the second stationary transmitting / receiving unit, is received by the second stationary transmitting / receiving unit. In other words, before the first stationary transmitting / receiving unit transmits the signal into the spatial area, a (planned) transmission time of the signal to be transmitted can be sent from the first stationary transmitting / receiving unit to the second stationary transmitting / receiving unit. In this way, the second stationary transmitting / receiving unit knows when the first stationary transmitting / receiving unit will transmit the signal and can transmit the reference signal at the same time.

[0022] According to one embodiment, the position information of the first stationary transmitting / receiving unit can be sent from this to the second stationary transmitting / receiving unit, which then sends this information together with its own position information to the mobile transmitting / receiving unit. In this way, it is ensured that the mobile transmitting / receiving unit, which may be moving during the transmitting / receiving process, receives the position information from both stationary transmitting / receiving units at the same time and thus in an identical position. The first and second stationary transmitting / receiving units can be synchronized in time. For example, they can be connected to one another in a common network, in particular in a wired network. In this case, the positions orPosition information of the stationary transmitting / receiving units may be stored in a memory and / or data server of the network so that the second stationary transmitting / receiving unit can retrieve the position information of the first stationary transmitting / receiving unit from there.

[0023] The second stationary transmitting / receiving unit can then send the two position information, for example by means of a communication signal, for example via a mobile radio network or a short-range communication, to the mobile transmitting / receiving unit. According to one embodiment, a reception time of a virtual line-of-sight signal between the first stationary transmitting / receiving unit and the mobile transmitting / receiving unit can be calculated based on a reception time of the line-of-sight signal transmitted by the second stationary transmitting / receiving unit and the received position information of the first and second stationary transmitting / receiving units by the mobile transmitting / receiving unit. Since the mobile transmitting / receiving unit knows its own position (for example by using a GNNS signal or aBased on the map information provided by an RSU, the RSU can adapt the reception time of the line-of-sight signal sent by the second stationary transmitting / receiving unit according to the different distances to the first and second stationary transmitting / receiving units and thus calculate a reception time of a virtual line-of-sight signal from the first stationary transmitting / receiving unit. Based on the difference between this reception time and that of the deflected, in particular reflected, signal, the mobile transmitting / receiving unit can calculate a distance to the object, taking into account an angle of incidence of the deflected, in particular reflected, signal, and thus determine its (relative) position. The angle of incidence can, for example, be measured by the mobile transmitting / receiving unit. The position of the object can, for example, also be only a position of part of the object.For example, the mobile transmitting / receiving unit can have its own radar sensor and thus determine a distance to a side of the object facing it, while the deflected, in particular reflected, signal can be used to determine a distance to a side of the object facing away from the mobile transmitting / receiving unit.

[0024] According to one embodiment, the second stationary transmitting / receiving unit can be a reflector, which reflects the signal transmitted by the first stationary transmitting / receiving unit and can be received as a reference signal by the mobile transmitting / receiving unit. The reflector can, for example, be a so-called "Reconfigurable Intelligent Surface" (RIS). The position of the reflector can also be stored in the network's memory or data server and sent from there to the mobile transmitting / receiving unit.

[0025] According to one embodiment, a plurality of stationary transmitting / receiving units can be arranged at different positions in the spatial area. In this case, a request to transmit the signal into the spatial area can be sent from the mobile transmitting / receiving unit to the plurality of stationary transmitting / receiving units, and the first stationary transmitting / receiving unit can be selected from the plurality of stationary transmitting / receiving units based on a position of the mobile transmitting / receiving unit and the object. In particular, the first stationary transmitting / receiving unit can be selected such that it detects an area of ​​the object that the mobile transmitting / receiving unit cannot detect from its position with its own sensors. The mobile transmitting / receiving unit can transmit the request signal, for example,by means of a communication signal, for example via a mobile network or short-range communication, to the mobile transmitter / receiver unit.

[0026] According to a further embodiment, the first transmitting / receiving unit may be a mobile transmitting / receiving unit, the second transmitting / receiving unit may be a first stationary transmitting / receiving unit, and the third transmitting / receiving unit may be a second stationary transmitting / receiving unit that has a line of sight with the mobile transmitting / receiving unit.

[0027] In this case, the mobile transmitting / receiving unit transmits the signal into the spatial area, and the first stationary transmitting / receiving unit receives the signal deflected, in particular reflected, by the object. Since the second stationary transmitting / receiving unit has a line-of-sight connection to the mobile transmitting / receiving unit, it can receive the transmitted signal as a line-of-sight signal and transmit the reception time in a communication signal via the shared network as a reference signal to the first stationary transmitting / receiving unit.

[0028] According to one embodiment, the position of the mobile transmitting / receiving unit and the position of the second stationary transmitting / receiving unit can be sent from the respective transmitting / receiving unit to the first stationary transmitting / receiving unit. In particular, the second stationary transmitting / receiving unit can transmit its position via the shared network. It is also possible for the positions of the stationary transmitting / receiving units to be stored in a memory and / or data server of the network, and for the first stationary transmitting / receiving unit to retrieve the position of the second stationary transmitting / receiving unit from there. The mobile transmitting / receiving unit can transmit its position to the first stationary transmitting / receiving unit, in particular via near-field communication, in order to achieve the lowest possible latency during data transmission.

[0029] According to one embodiment, a reception time of a virtual line-of-sight signal between the mobile transceiver unit and the first stationary transceiver unit can be calculated by the mobile transceiver unit based on the reception time of the line-of-sight signal at the second stationary transceiver unit and the position information of the mobile transceiver unit and the second stationary transceiver unit. Since the first stationary transceiver unit knows its own position (for example, through the value stored in the network's memory / data server), it can adjust the reception time of the line-of-sight signal received from the second stationary transceiver unit according to the different distances to the mobile and second stationary transceiver units, thus calculating a reception time of a virtual line-of-sight signal from the mobile transceiver unit.Based on the difference between this reception time and that of the deflected, particularly reflected, signal, the mobile transmitting / receiving unit can calculate a distance to the object, taking into account the angle of incidence of the deflected, particularly reflected, signal, and thus determine its (relative) position. The angle of incidence can be measured, for example, by the first stationary transmitting / receiving unit. The position of the object can, in particular, be only a position of a part of the object.For example, the first stationary transmitting / receiving unit can have its own radar sensor and thus determine a first distance from a side of the object facing the first stationary transmitting / receiving unit, while the deflected, in particular reflected, signal can be used to determine a second distance from the first stationary transmitting / receiving unit to a side of the object facing away from the first stationary transmitting / receiving unit. In this way, the first stationary transmitting / receiving unit can expand its field of view and provide more precise information about the area it is observing.

[0030] A transmitting / receiving unit according to the invention preferably comprises a transmitter and a receiver, as well as a computing unit or a computing unit system of computing units. More preferably, the transmitting / receiving unit comprises a storage medium with a computer program comprising instructions that cause the transmitting / receiving unit to carry out the method according to the invention, as described above. The transmitting / receiving unit can in particular be designed as a mobile or stationary transmitting / receiving unit. In particular, each of the stationary transmitting / receiving units and each mobile transmitting / receiving unit can comprise a computing unit. This can be integrated into the respective transmitting / receiving units or arranged separately from them. The computing units can receive data from the transmitting / receiving units and send data to them. Likewise, the computing units can exchange data with one another, e.g., by means of a communication interface.

[0031] It is also possible that at least for the stationary transmitting / receiving unit there is only one computing unit which carries out the calculations for all stationary transmitting / receiving units.

[0032] The transmitting / receiving system according to the invention comprises at least two stationary transmitting / receiving units arranged along a spatial area and each containing at least one transmitter and at least one receiver. According to one embodiment, the at least two transmitting / receiving units can be synchronized in time. In particular, a plurality of stationary transmitting / receiving units can be present, which are connected to one another in a network, in particular a wired network.

[0033] Furthermore, the transmitting / receiving system includes at least one mobile transmitting / receiving unit configured to move through the spatial area and having at least one transmitter and at least one receiver, as well as a computing unit or a computing unit system. The transmitting / receiving system is configured to carry out the method according to the invention.

[0034] According to one embodiment, the mobile transmitting / receiving unit and the stationary transmitting / receiving units can be configured to transmit and receive signals via a radio network and / or via a direct radio connection. The radio network can be, for example, a cellular network, and the direct radio connection can be a near-field communication system, such as DSRC.

[0035] The implementation of a method according to the invention in the form of a computer program or computer program product with program code for carrying out all of the method steps is also advantageous, as this entails particularly low costs, in particular if an executing transmitting / receiving unit and / or an executing transmitting / receiving system, each with a computing unit or a computing unit system, is also used for further tasks and is therefore already present. Finally, a machine-readable storage medium is provided with a computer program stored thereon, as described above. Suitable storage media or data carriers for providing the computer program are, in particular, magnetic, optical and electrical memories, such as hard disks, flash memories, EEPROMs, DVDs, etc. Downloading a program via computer networks (Internet, Intranet, etc.) is also possible. Such a download can be wired or wireless.wired or wireless (e.g., via a Wi-Fi network, a 3G, 4G, 5G, or 6G connection, etc.). Further advantages and embodiments of the invention will become apparent from the description of the accompanying drawings.

[0036] The invention is schematically illustrated in the drawings using exemplary embodiments and will be described below with reference to the drawings. Identical elements are provided with identical reference numerals and will therefore not be described repeatedly unless necessary.

[0037] Short description of the drawings

[0038] Figure 1 schematically shows a determination of a position of an object by a mobile transmitting / receiving unit by means of signal deflection, in particular signal reflection, according to an embodiment of the invention.

[0039] Figure 2 schematically shows a determination of a position of an object by a stationary transmitting / receiving unit by means of signal deflection, in particular signal reflection, according to a further embodiment of the invention.

[0040] Embodiment(s) of the invention

[0041] Figure 1 schematically shows a determination of a position of an object by a mobile transmitting / receiving unit by means of signal deflection, in particular signal reflection, according to an embodiment of the invention.

[0042] Shown is a spatial area 100, which in the present case comprises a road intersection 101 at which a building 10 is located. A vehicle 20 is approaching intersection 101 on a road section 101a entering intersection 101 from the left, and a cyclist 15 is approaching intersection 101 on a road section 101b entering the intersection from above.

[0043] In this case, the vehicle 20 represents a mobile transmitting / receiving unit 20 and can exchange communication signals with stationary transmitting / receiving units 21a, b arranged in the spatial area 100 via V2X communication. These communication signals can be used both for data transmission and as sensor signals. For this purpose, the physical layer of the communication signals can be accessed. The communication signals can be transmitted from the vehicle 20 to the stationary transmitting / receiving units 21a, b via a WLAN or cellular network or by means of near-field communication. Furthermore, both the vehicle 20 and the stationary transmitting / receiving units 21a, b can have various sensors, such as radar, lidar, cameras, etc. (not shown). In this case, the stationary transmitting / receiving units 21a, b are connected to one another via a wired network 22 and are synchronized in time.

[0044] Due to the building 10 located at the intersection 101, the vehicle's own sensors, such as the radar sensor, have only a limited view of the road section 101b (and thus the approaching cyclist 15). In this case, the vehicle can send a request to transmit a signal into the spatial area to the stationary transmitting / receiving units 21a, b. Based on the position of the vehicle 20 and the cyclist 15 as the object 15 to be detected, the transmitting / receiving unit 21b is selected as the first stationary transmitting / receiving unit, which then transmits a signal into the spatial area 100. The signal can be, for example, a sensor signal, such as a radar or lidar signal. This is transmitted to the cyclist 15 oron his bicycle, in particular reflected, and the deflected, in particular reflected, signal is received by the vehicle 20 (indicated by the arrows from the first stationary transmitting / receiving unit 21 b via the cyclist 15 to the vehicle 20).

[0045] Since the vehicle 20 has no line of sight to the stationary transmitting / receiving unit 21, no line of sight signal can be received from the stationary transmitting / receiving unit to determine the position of the cyclist 15. Instead, a second stationary transmitting / receiving unit 21a transmits a line of sight signal as a reference signal to the vehicle (indicated by the arrow from the second stationary transmitting / receiving unit 21a to the vehicle 20) at a predetermined time that is in a specific temporal relationship to the time at which the first stationary transmitting / receiving unit 21b transmits the signal into the spatial area. Furthermore, the second stationary transmitting / receiving unit 21a receives (or already knows) a position of the first stationary transmitting / receiving unit 21b and transmits this, together with its own position, to the vehicle 20.The positions of the stationary transmitting / receiving unit can be stored, for example, in a memory and / or data server (not shown) of the network 22 and retrieved from there.

[0046] Since the vehicle knows its own position (for example, by using a GNNS signal), it can adjust the reception time of the line-of-sight signal transmitted by the second stationary transceiver unit according to the different distances to the first and second stationary transceiver units 21a, b and thus calculate a reception time of a virtual line-of-sight signal from the first stationary transceiver unit 21a. Based on the difference between this reception time and that of the deflected, in particular reflected, signal, the vehicle 20 can calculate a distance to the cyclist 15, taking into account an angle of incidence of the deflected, in particular reflected, signal, and thus determine the cyclist's (relative) position.

[0047] Figure 2 schematically shows a determination of a position of an object by a stationary transmitting / receiving unit by means of signal deflection, in particular signal reflection, according to a further embodiment of the invention.

[0048] The situation in Fig. 2 differs from that in Fig. 1 only in that here the vehicle 20 transmits a signal into the spatial area 100, and the first stationary transmitting / receiving unit 21b determines the position of a part of the cyclist 15 or their bicycle facing away from it. In this case, the vehicle can, for example, transmit its position data into the spatial area 100 at regular intervals using a radio network or near-field communication, and such a signal can be deflected by the cyclist 15, in particular reflected, and received by the first stationary transmitting / receiving unit (indicated by the arrows from the vehicle 20 via the cyclist 15 to the first stationary transmitting / receiving unit 21b).

[0049] Since the second stationary transmitting / receiving unit 21a is in line of sight with the vehicle, it can receive a line-of-sight signal of the transmitted signal (indicated by the arrow from the vehicle 20 to the second stationary transmitting / receiving unit 21a) and transmit a reference signal indicating or containing a time of reception of the line-of-sight signal via the network 22 to the first transmitting / receiving unit 21b (indicated by the dashed arrows next to the network 22). The vehicle 20 and the second stationary transmitting / receiving unit 21a can also transmit their positions to the first stationary transmitting / receiving unit 21b, or the first stationary transmitting / receiving unit 21b can retrieve the position of the second stationary transmitting / receiving unit 21a from the storage / data server of the network 22 or have stored or know it itself.Since the first stationary transmitting / receiving unit 21b knows its own position (for example, through the value stored in the network's memory / data server), it can adjust the reception time of the line-of-sight signal received by the second stationary transmitting / receiving unit 21a according to the different distances to the vehicle 20 and the second stationary transmitting / receiving unit 21a, and thus calculate a reception time of a virtual line-of-sight signal from the vehicle 20. Based on the difference between this reception time and that of the deflected, in particular reflected, signal, the first stationary transmitting / receiving unit 21b can calculate a position of the part of the object facing away from it, in this case the front wheel of the bicycle, taking into account an angle of incidence of the deflected, in particular reflected, signal.

Claims

Claims 1. A method for determining a position of an object (15) by means of signal deflection, in particular signal reflection, wherein a signal transmitted by a first transmitting / receiving unit (21b, 20) into a spatial area (100) is deflected via the object (15) in the spatial area (100) and received by a second transmitting / receiving unit (20, 21b); a reference signal transmitted by a third transmitting / receiving unit (21a) to the second transmitting / receiving unit (20, 21b) is received by the second transmitting / receiving unit (21b, 20);a position indication of the first transmitting / receiving unit (21b, 20) and a position indication of the third transmitting / receiving unit (21a) are received by the second transmitting / receiving unit (20, 21b), and a position of the object (10) is determined by the second transmitting / receiving unit (20, 21b) based on the deflected, in particular reflected, emitted signal, the reference signal, the position indication of the first transmitting / receiving unit (21b, 20) and the position indication of the third transmitting / receiving unit (21a); 2. The method according to claim 1, wherein the first transmitting / receiving unit (21b, 20) is a first stationary transmitting / receiving unit (21b), the second transmitting / receiving unit (20, 21b) is a mobile transmitting / receiving unit (20) and the third transmitting / receiving unit (21a) is a second stationary transmitting / receiving unit (21a) which has a line of sight with the mobile transmitting / receiving unit (20), and wherein the reference signal is a line of sight signal which is transmitted from the second stationary transmitting / receiving unit (21a) to the mobile transmitting / receiving unit (20) in a specific temporal relationship to the transmitted signal of the first stationary transmitting / receiving unit (21b).

3. The method according to claim 2, wherein before the first stationary transmitting / receiving unit (21b) transmits the signal into the spatial area (100), a transmission time of the signal to be transmitted, transmitted from the first stationary transmitting / receiving unit (21b) to the second stationary transmitting / receiving unit (21a), is received by the second stationary transmitting / receiving unit (21a).

4. The method according to claim 2 or 3, wherein a position indication of the first stationary transmitting / receiving unit (21b) is sent from the first stationary transmitting / receiving unit (21a) to the second stationary transmitting / receiving unit (21a), and a position indication of the first stationary transmitting / receiving unit (21b) and the position indication of the second stationary transmitting / receiving unit (21a) are sent from the second stationary transmitting / receiving unit (21b) to the mobile transmitting / receiving unit (20).

5. The method according to any one of claims 2 to 4, wherein a reception time of a virtual line-of-sight signal between the first stationary transmitting / receiving unit (21b) and the mobile transmitting / receiving unit (20) is calculated based on a reception time of the line-of-sight signal transmitted by the second stationary transmitting / receiving unit (21b) and the received position information of the first and second stationary transmitting / receiving units (21b, a) from the mobile transmitting / receiving unit (20).

6. The method according to any one of claims 2 to 5, wherein the second stationary transmitting / receiving unit (21a) is a reflector at which the signal transmitted by the first stationary transmitting / receiving unit (21b) is reflected and received as a reference signal by the mobile transmitting / receiving unit (20).

7. Method according to one of claims 2 to 6, wherein a plurality of stationary transmitting / receiving units (21a, b) are arranged at different positions in the spatial area (100), a request to transmit the signal into the spatial area (100) is sent from the mobile transmitting / receiving unit (20) to the plurality of stationary transmitting / receiving units (21a, b), and the first stationary transmitting / receiving unit (21b) is selected from the plurality of stationary transmitting / receiving units (21a, b) based on a position of the mobile transmitting / receiving unit (20) and the object (15).

8. The method according to claim 1, wherein the first transmitting / receiving unit (21b, 20) is a mobile transmitting / receiving unit (20), the second transmitting / receiving unit (20, 21b) is a first stationary transmitting / receiving unit (21b) and the third transmitting / receiving unit (21a) is a second stationary transmitting / receiving unit (21a) which has a line of sight with the mobile transmitting / receiving unit (20), and wherein the reference signal is a communication signal which contains a time at which the second stationary transmitting / receiving unit (21a) received a line of sight signal from the mobile transmitting / receiving unit (20).

9. The method according to claim 8, wherein the position information of the mobile transmitting / receiving unit (20) and the position information of the second stationary transmitting / receiving unit (21a) are sent from the respective transmitting / receiving unit (20, 21a) to the first stationary transmitting / receiving unit (21b).

10. The method according to claim 8 or 9, wherein a reception time of a virtual line-of-sight signal between the mobile transmitting / receiving unit (20) and the first stationary transmitting / receiving unit (21b) is calculated based on the reception time of the line-of-sight signal at the second stationary transmitting / receiving unit (21a) and the positions of the mobile transmitting / receiving unit (20) and the second stationary transmitting / receiving unit (21a) by the first stationary transmitting / receiving unit (21b).

11. Transmitting / receiving unit (20, 21b) which is configured to carry out the method according to one of the preceding claims, wherein the transmitting / receiving unit (20, 21b) is designed in particular as a mobile or stationary transmitting / receiving unit (20, 21b).

12. Transmitting / receiving system comprising at least two stationary transmitting / receiving units (21a, b) which are arranged in a spatial area (100) and each contain at least one transmitter and at least one receiver, wherein the at least two stationary transmitting / receiving units (21a, b) are in particular synchronized in time, and at least one mobile transmitting / receiving unit (20) which is configured to move through the spatial area (100) and contains at least one transmitter and at least one receiver, wherein the transmitting / receiving system is configured to carry out the method according to one of claims 1 to 10.

13. Transmitting / receiving system according to claim 12, wherein the mobile transmitting / receiving unit (20) and the stationary transmitting / receiving units (21a, b) are configured to transmit and receive signals via a radio network and / or via a direct radio connection.

14. Computer program comprising instructions which cause the transmitting / receiving unit (20, 21b) according to claim 11 and / or the transmitting / receiving system according to claim 12 or 13 to carry out the method according to one of claims 1 to 10.

15. A computer-readable data carrier on which the computer program according to claim 14 is stored.

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