Method and device for highly accurate determination of the position and / or orientation of an object to be located, as well as a fixed station for a mobile communication system

Abstract

Method for highly accurate determination of the position and / or orientation of a vehicle (10) to be located, which is designed for communication in a wireless communication network, wherein the vehicle (10) transmits short-duration broadband pulses to surrounding fixed stations (31-35), which are answered by the surrounding fixed stations (31-35) upon receipt by an immediate return pulse, wherein the time of flight of the transmitted pulse until the arrival of the return pulse from at least one of the surrounding fixed stations (31-35) is measured in the vehicle (10), wherein each transmission of a pulse is carried out successively by a number of antenna elements (176) with a respective transreceiver attached to different positions of the vehicle (10),wherein for each attached antenna element (176) a transceiver (170) is located near a position of the antenna element (176) and a communication module (110) is connected to the transceivers (170) of the antenna elements (176) attached at the different positions, wherein the communication module (110) is designed to request the different transceivers (170) successively to transmit the broadband pulse of short duration or to assign them respective planned times for the successive transmission of the broadband pulses, and the time until the arrival of the respective response pulse at the individual antenna elements (176) is measured by means of the respective transceiver (170),wherein the determination of the positions of the antenna elements (176) of the vehicle (10) to be located is based on at least one intersection calculation with the resulting at least three travel times and the known positions of the antennas of the fixed stations (31 - 35), and the position and / or orientation of the vehicle (10) is determined from the determined antenna element positions (176) on the vehicle (10), wherein the antennas of each fixed station (31 - 35) are designed in the form of antenna arrays (310) consisting of a number of antenna elements (31A, 31B, 31C, 31E), wherein for the return, a single antenna element (31E) is used to radiate the response pulse, wherein three different travel time measurements are carried out with three different single antenna elements (31A, 31B, 31C) of the antenna array (310). are carried out sequentially, selecting the individual antenna elements (31A, 31B, 31C) accordingly,that they are as far apart as possible.

Description

[0001] The invention relates to a method for the highly accurate determination of the position and / or orientation of a vehicle to be located. The proposal further relates to a device for the highly accurate determination of the position and / or orientation of a vehicle to be located, as well as a base station for a mobile radio communication system.

[0002] For the scenario of vehicles equipped with radio communication modules that communicate directly with each other in public traffic, whether for cooperative or autonomous driving, or for participation in mobile communications and connection to the Internet or the provision of other data services, high reliability in safety-critical applications is essential or very important for the customer.

[0003] Navigation aids have become a part of many people's everyday lives. They help people reach specific locations in both rural and urban areas and minimize travel time. Vehicle applications, in particular, typically rely on satellite navigation, which incorporates information from signals from other vehicle sensors to increase robustness. Satellite navigation is known as GNSS (Global Navigation Satellite System).

[0004] In densely built-up areas, however, satellite navigation reaches its technical limitations, as satellite signals in narrow urban canyons often cannot be received directly, but only indirectly after (multiple) reflections from building walls. This can sometimes distort the satellite-based localization result to such an extent that it is, at least temporarily, unsuitable for correcting the position estimate from the (less accurate) vehicle sensor signals.

[0005] The localization task is even more difficult inside buildings. Since satellite signals generally do not penetrate ceilings and walls, a method must be developed for indoor navigation applications that operates entirely without satellite signals. This requires meeting significantly higher accuracy requirements than outdoor navigation. While this is necessary for autonomous driving in a parking garage, the most important vehicle application, to avoid collisions with other vehicles or parking garage obstacles, for electronic museum guides, a typical non-vehicle application, even an inaccuracy of several meters poses the risk of navigating the user to the wrong room.

[0006] A non-satellite-based alternative for indoor localization could be the field strength of a Wi-Fi network, which is often already present. This requires the signal to be measured using the end device, such as an add-on unit in a vehicle navigation system or an electronic museum guide, and compared with maps of the Wi-Fi network's characteristic field strength distribution. This principle also underlies location determination using the Earth's magnetic field, which is significantly altered by building characteristics. However, the effort required to create and continuously update the field strength maps is significant, especially given the high accuracy requirements.

[0007] Another option involves installing small transmitters inside a building that transmit, for example, Bluetooth Low Energy (BLE) signals. The location can then be determined using trilateration: the signals from three transmitters are used to determine their respective distances from the end device, and the position is calculated using the known transmitter locations and the determined distances by calculating the intersection point. Similar to radar technology, distance measurements can be performed on transmitted signals. These signals are either reflected back or immediately re-transmitted by the transmitter when a measurement signal from the vehicle arrives. Another option is a field strength measurement, which, with the help of a sufficiently accurate map of the field strength distribution during standard transmission, also allows the distance to the transmitter to be determined.

[0008] An example of a positioning system based on GPS signal analysis is described in US2004 / 0193372 A1, also for the platooning application. The GPS system is improved by combining it with Bluetooth. Position information is exchanged with a vehicle in the platoon via a Bluetooth connection. During operation, the vehicles communicate satellite data via the Bluetooth connections. This makes it possible to use Bluetooth radio connections to reduce the number of satellites required for the GPS system without losing measurement accuracy. The possibility of using UWB communication as an alternative to Bluetooth communication is also mentioned.

[0009] Another example of such a system is described in US 2015 / 0269845 A1. This document emphasizes the need for highly accurate synchronization of the vehicles' clocks in order to measure the vehicles' precise position using time-of-flight measurements. The solution is suggested to be the use of high-precision clocks in GNSS systems.

[0010] From DE 10 2015 122 145 A1 a method for improved positioning of a mobile station or a handset within a mobile radio network is known.The method comprises the steps of: transmitting at least three radio signals between the mobile station and a corresponding number of at least three base stations, wherein at least each of the three radio signals comprises temporal information indicating a transmission time of the corresponding radio signal; calculating a time delay for each of the at least three radio signals based on a difference between an arrival time and the transmission time of the corresponding radio signal; retrieving, for each of the at least three radio signals, information about the transmission path losses of the corresponding radio signal from a data memory; calculating a distance of the mobile station from the corresponding base station for each of the at least three radio signals based on the time delay and the information about the transmission path losses; and determining a location of the mobile station based on the trilateration of the at least three distances.

[0011] US 2019 066 504 A1 discloses a ground-based radio system called an Autonomous Transceivers Positioning System ("ATPS") that performs fully autonomous tracking of multiple moving objects and determines the position and velocity components (speed and direction) of a moving object or the stationary position of an object. For a moving object, the system provides position determination with an accuracy of several centimeters and velocity determination with an accuracy of centimeters per second. The ATPS system tracks the position of multiple objects simultaneously and continuously, as long as the objects are within the operating range of the wireless ATPS system.The ATPS incorporates RFID-inspired components, including advanced autonomous wireless interrogators with multiple fixed locations within the system's defined workspace and multiple autonomous wireless responders attached to moving and / or stationary objects.

[0012] WO 2019 143 437 A1 describes positioning techniques that enable the localization of a target user equipment (UE) in a wireless communication network served by one (or a number of) different radio access technologies (RATs). These techniques include field strength measurements, time-of-flight measurements, and angle measurements.

[0013] Due to the wavelength of Wi-Fi and BLE signals of approximately 12.5 cm, corresponding to a frequency of 2.5 GHz, localization with sufficiently high accuracy is theoretically possible. Since the permitted Wi-Fi and BLE transmission power is high enough to achieve interference-free or minimal information transmission even with larger antenna spacing and thus acceptable system costs, it must be assumed for indoor navigation applications that Wi-Fi and BLE signals cannot be received directly from every location, but only indirectly after (multiple) reflections from walls and obstacles. The localization accuracy theoretically possible with a wavelength of 12.5 cm can only be approximately achieved under these conditions if the (multiple) reflections are compensated for using dedicated computational models.On the one hand, these calculation models are very complex and therefore time-consuming to develop; on the other hand, they must be continuously kept up-to-date in order to take into account possible structural changes to the building during system operation over several years.

[0014] The required work is eliminated by increasing the antenna density, so that Wi-Fi and BLE signals can largely be received directly, thus reducing the proportion of (multiple) reflections. Generic models are therefore sufficient to compensate for these reflections in indoor localization. These models are simpler to implement and no longer require continuous updating.

[0015] For indoor navigation applications with particularly high accuracy requirements, it may be necessary to extend the trilateration method described above with an ultra-wide-band (UWB) approach. The principle of this approach is to transmit a very limited pulse with a duration of <1 ns and a pronounced edge steepness corresponding to a bandwidth of several hundred MHz from a transmitter of an autonomous vehicle or an electronic museum guide, for example. Due to the principle, the radiated power of a UWB pulse is distributed across the very wide bandwidth. This results in only a slightly increased radiated power per bandwidth interval, so that the limit of the specific radiated power of another communication type emitted by the same station is practically not exceeded by the additional UWB emission in the respective interval.

[0016] Despite the low power of the UWB pulse, receivers distributed indoors must be capable of flawlessly detecting the UWB pulse and sending a response back to the transmitting device. The distance between the receivers distributed indoors must therefore not exceed a maximum value dependent on the given boundary conditions and should ideally be selected so that there is line of sight to at least three receivers from every point in the indoor area. The reason for this requirement is the need to be able to detect and ignore reflections. Without direct line of sight, only reflected signals or even multiple reflections would be present. Complex computational models would be required to determine the distance between transmitter and receiver from this.These models would need to be kept up to date to reflect any structural changes. With a direct line of sight between transmitter and receiver, it is possible to detect and ignore reflections and multiple reflections. The distance calculation can then be determined with high accuracy based on the direct pulse transit time.

[0017] Under these conditions, by precisely measuring the time between the transmission of the original pulse and the arrival of the reflected pulse by at least three receivers, it is possible to determine the distances between the terminal devices and the transmitters and, using the transmitter locations and the distances, to determine the terminal device position.

[0018] The pronounced synchronization of currently available electronic clocks allows the error in the determined position to be kept below 1 cm. The advantage of this high accuracy is offset by the disadvantage of the high costs due to the large number of receivers required to reflect the transmitted pulses.

[0019] US 2019 / 0361109 A1 discloses a detection system that is primarily used in an industrial environment in a building. However, the system of a tracking device can also be used in vehicles, for example in urban areas or where localization using GNSS is not possible. The tracking device provides localization in which the position of a moving object relative to a transmitter or vice versa is determined using a first and a second reference signal, each dependent on a transmitted or received signal. According to one example, the device comprises the measurement of a "direct time of flight (TOF)" using at least one transmitter and at least one receiver.Another example involves using an interrogator with three antennas and four channels to increase localization. Here, too, the three antennas have direct contact with the transponder. Two or three receivers assigned to the interrogator receive the signal emitted by the transponder, enabling hyperbolic or triangular location of the transponder and thus the object.

[0020] The invention aims to find a method for highly accurate self-localization for vehicles, in particular vehicles that move inside buildings.

[0021] This object is achieved by a method for determining the position and / or orientation of a vehicle to be located according to claim 1, a device for determining the position and / or orientation of a vehicle to be located according to claim 7 and a base station for a mobile radio communication system according to claim 12.

[0022] The dependent claims contain advantageous developments and improvements of the invention according to the following description of these measures.

[0023] The solution to the problem lies in a method for the highly accurate determination of the position and / or orientation of a vehicle designed for communication in a wireless communications network. This can be implemented in the form of a mobile radio communications network. For highly accurate position and / or orientation determination, the vehicle transmits short, broadband pulses to the surrounding base stations. Upon receipt, these pulses are immediately answered by the surrounding base stations. For precise position and / or orientation determination, a measurement of the propagation time of the transmitted pulse until the arrival of the response pulse of the return signal from one of the surrounding base stations is carried out in the vehicle.The pulse is repeatedly transmitted one after the other by a number of antenna elements mounted at different positions on the vehicle, and the travel time to and from each individual antenna element is measured. From this travel time, the position of the vehicle's antenna element is determined based on the measured travel times and the known positions of the fixed stations. An intersection point calculation is performed. If measurement results are available for three different fixed stations, the intersection point calculation corresponds to a trilateration calculation. If more measurement results are available, the intersection point calculation can be performed using a multilateration calculation. Based on the position of the intersection points, the position of the antenna elements is calculated. Theoretically, it is possible for two return signals from different fixed stations to arrive at the vehicle at the same time.If a disturbance occurs here, the measurement must be repeated. With a moving vehicle, the conditions will quickly change, eliminating the disturbance.

[0024] In a preferred variant, the short-duration broadband pulses can correspond to ultra-wideband (UWB) pulses. These are pulses emitted in the UHF or SHF frequency band. They are particularly well suited for distance measurement. UWB pulses have a high bandwidth of approximately 500 MHz or more, which requires a short duration in the time domain of a few or fractions of nanoseconds. Therefore, UWB pulses are also used for distance measurement, but only for short distances, as they emit only low radiant energy, and their range is correspondingly limited.

[0025] For this method, the antennas of the fixed stations are designed as antenna arrays consisting of a number of antenna elements. For the time-of-flight measurement, either several antenna elements radiate the measurement pulse in parallel or a single antenna element is used to radiate the measurement pulse. 5G antennas for the so-called 26 GHz frequency band are particularly suitable for use in this measurement method. Their widespread implementation is expected as soon as the current rollout of 5G telecommunications technology for the 3.5 GHz frequency band is completed. Propagation conditions in the 26 GHz band are worse than in the frequency ranges up to 10.6 GHz, as radio signals in this frequency range are subject to significantly high attenuation.Therefore, a reduction in the distance between the fixed stations is necessary, which will allow more frequent line of sight connections and reduce the problem of multiple reflections.

[0026] Three different time-of-flight measurements are carried out one after the other using three different individual antenna elements of the antenna array in the base stations. The individual antenna elements are selected so that they are as far apart as possible. These three individual measurements provide results for three different positions of three different antenna elements. Carrying out the time-of-flight measurements one after the other is advantageous because in this case only one antenna element needs to be present in the remote station (in this case the vehicle). This results in cost advantages. However, if not only the position of the vehicle but also its orientation, for example in the form of the yaw angle, is to be determined, multiple antenna elements are required, e.g. in the form of individual antenna elements located further apart in the remote station (in this case the vehicle).

[0027] The position of the vehicle-mounted antenna element(s) can then be calculated using trilateration based on the time-of-flight measurements to the three antenna elements of the base station's antenna array. However, the accuracy of the position determination also depends on the distance between the antenna elements of the antenna array(s).

[0028] In this case, it is also advantageous if, when response pulses from two or more different nearby fixed stations arrive at one antenna element of the vehicle, the position determinations of the antenna element of the vehicle to be located are averaged. This can further increase the accuracy of the position determination.

[0029] It is also advantageous if the propagation time measurements from the various antenna elements of the vehicle for the pulse returned from a fixed station are subjected to a plausibility check. A propagation time that is rejected as erroneous during the plausibility check is not used for the intersection point calculation. This prevents a propagation time measurement with a larger error from degrading the accuracy of the position determination. Under certain circumstances, it is possible that a measurement pulse is reflected by obstacles and does not return directly to an antenna. In this case, the propagation time measurement no longer corresponds to the direct distance measurement between the object vehicle and the fixed station and is therefore corrupted.

[0030] In one variant, the plausibility check is based on a comparison of the measured propagation times, taking into account the spatial proximity of the antenna elements mounted on the vehicle. Those propagation times whose propagation times do not correlate with the spatial proximity of the antennas are rejected as faulty. In other words, the plausibility check takes advantage of the fact that there will be a propagation time measurement based on direct reception. If other propagation time measurements deviate significantly from this beyond the known distance from the vehicle's antennas, it is assumed that they are based on reflected reception. These propagation times are then rejected as faulty.

[0031] By weighting the runtime measurements depending on the results of the plausibility check, the accuracy of the position determination can also be increased.

[0032] Finally, according to the method, the position and orientation of the vehicle are determined from the determined antenna element positions on the vehicle. The vehicle position and / or orientation is required for a variety of purposes, including navigation. However, even if the vehicle is equipped with automatic driving, the position and / or orientation information is essential to avoid a collision with an obstacle or another road user. But even if the vehicle is not a vehicle, but a pedestrian, for example, the accuracy of the position and / or orientation determination is just as important for functioning navigation, particularly within buildings.

[0033] A particularly advantageous variant for determining the position and / or orientation of the vehicle is achieved by applying a trilateration or multilateration calculation based on the time-of-flight measurements of an antenna element mounted on the vehicle for the pulses returned by three or more different fixed stations. This allows the position to be determined to within a few centimeters and the orientation to within less than 10°. In this case, the distances between the fixed stations are large enough to perform trilateration with high accuracy. The smaller the distances between the fixed stations, the greater the impact of errors in the time-of-flight measurement on the position and / or orientation determination.

[0034] In another embodiment, the invention also relates to a corresponding device for determining the position and / or orientation of a vehicle to be located. The device is equipped with a communications module for communication in a wireless communications network. The device is also equipped for communication with the surrounding fixed stations of the communications network. The device is characterized by a number of antenna elements mounted on the vehicle at various positions, with one transceiver being provided for each mounted antenna element, which is located close to the position of the antenna element. The advantage of positioning it close to the antenna element is that only short connecting lines are required between the antenna element and the transceiver. This is necessary to avoid falsifying the propagation time measurements as much as possible.The transceiver generates a short-duration, broadband pulse that is radiated from the antenna element to the surrounding base stations and receives a response pulse immediately returned by the surrounding base stations. It also measures the propagation time of the radiated pulse until the response pulse arrives from one of the surrounding base stations. The pulse is transmitted by the various antenna elements mounted at different positions on the vehicle, and the propagation time is measured by the transceivers assigned to the individual antenna elements. With this arrangement, the position and / or orientation of the vehicle can be determined very precisely using common intersection point calculation methods, in particular trilateration or multilateration.

[0035] The communication module is connected to the transceivers of the antenna elements mounted at the various positions. The communication module is designed to request the various transceivers to transmit the short-duration broadband pulse one after the other, or to assign them specific scheduled times for the sequential transmission of the broadband pulses. This is necessary to prevent interference between the pulses, which is a risk when the pulses are transmitted simultaneously from different antennas.

[0036] It is also advantageous if the communication module is also designed for communication in a mobile network and is configured to send an announcement message for the position and / or orientation determination measurement phase to the surrounding base stations. This message announces the arrival of a broadband pulse and requests the base stations to respond to the incoming pulse by immediately returning the response pulse. Only if the response pulse is transmitted immediately can the propagation time measurement be calculated directly by calculating the difference between the time of transmission of the measurement pulse and the time of arrival of the response pulse.

[0037] In addition, it is advantageous if the base stations are requested with the announcement message to send their identification to the communication unit in a further pulse or a further pulse sequence or in a message via a logical channel of the wireless communication system following the transmission of the response pulse.

[0038] In a further embodiment, the invention also relates to a vehicle, wherein a device according to the invention is installed in the vehicle.

[0039] Finally, in a further embodiment, the invention also relates to a base station for a mobile radio communication system with an antenna arrangement and a transmitting and receiving unit. The transmitting and receiving unit is designed to receive an announcement message for the position and / or orientation determination measurement phase of a vehicle to be located and, in response to the receipt of the announcement message, to switch to an operating mode in which it waits for the arrival of the short-duration broadband pulse and, upon receipt of the pulse, immediately returns the response pulse.

[0040] Furthermore, the transmitting and receiving unit is configured to receive another announcement message, which places the base station in a different operating mode, in which it designates three antenna elements of the antenna array, each of which sends a response pulse back to the vehicle upon arrival of the broadband pulse for separate time-of-flight measurements. The time-of-flight measurements take place sequentially.

[0041] An embodiment of the invention is illustrated in the drawings and is explained in more detail below with reference to the figures.

[0042] They show: Fig. 1 the principle of vehicle communication via mobile radio; Fig. 2 the line-of-sight conditions between fixed stations of a mobile radio communication system located at intervals of 50 - 100 m in a rural area; Fig. 3 the line-of-sight conditions between fixed stations of a mobile radio communication system located at intervals of 50 - 100 m in an urban area; Fig. 4 the line-of-sight conditions between fixed stations of a mobile radio communication system installed at intervals of 30 - 50 m in a parking garage; Fig. 5 shows an example of an antenna arrangement in the form of an antenna array as used in a base station of a 5G mobile radio system; Fig. 6 shows an example of an antenna arrangement and the associated transceivers in a vehicle; Fig. 7 a block diagram for the vehicle electronics of a motor vehicle; Fig. 8 a first example of the line of sight conditions from a vehicle to several surrounding fixed stations in a parking garage; and Fig. 9 a second example of the line of sight conditions from a vehicle to several surrounding fixed stations in the parking garage.

[0043] The present description illustrates the principles of the inventive disclosure. It is thus understood that those skilled in the art will be able to devise various arrangements that, although not explicitly described herein, embody the principles of the inventive disclosure and are also intended to be protected within their scope.

[0044] Fig. Figure 1 shows the principle of vehicle communication via mobile radio. The vehicles are designated by reference number 10.

[0045] The term "vehicle" is understood as a collective term, including motor vehicles with internal combustion engines or electric motors, bicycles with and without electric motors, and other human-powered vehicles, such as wheelchairs; vehicles with one, two, four, or more wheels; motorcycles, passenger cars, trucks, buses, agricultural vehicles, or construction machinery. This list is not exhaustive and also includes other vehicle categories. These include aircraft, watercraft, and rail vehicles.

[0046] The vehicles in Fig. 1 are each equipped with a so-called on-board unit 110, which serves as a communication module for a mobile radio communication system. This on-board unit 110 corresponds to a mobile radio network subscriber station within the meaning of the disclosure of the invention. Examples of public mobile radio networks are the aforementioned LTE and 5G mobile radio communication systems. In these mobile radio communication systems, the typical mobile radio network subscriber stations are referred to as UE, corresponding to user equipment. In the case illustrated, the on-board unit 110 is also a fully-fledged mobile radio network subscriber station in a passenger car. All messages from the vehicles (uplink) and to the vehicles (downlink) are either routed via a mobile radio base station 30 that serves a mobile radio cell, or, in the case of direct vehicle communication (sidelink), are exchanged directly between the vehicles.If the vehicles 10 are within this cell, they are logged on or registered with the base station 30. If they leave the cell, they are transferred to the neighboring cell (handover) and deregistered or deregistered accordingly at the base station 30. The base station 30 also provides access to the Internet, so that the vehicles 10 and all other mobile subscribers in the cell are supplied with Internet data. For this purpose, the base station 30 is connected to the EPC 40 (Evolved Packet Core) via the so-called S1 interface. Central computers 50 or, more generally, the servers of a service provider can also be reached via the Internet 300 or another wide area network (WAN).

[0047] Such mobile communications technologies are standardized and reference is made to the relevant specifications of mobile communications standards.

[0048] LTE primarily stands for high transmission rates and short response times. Currently, intensive work is underway on the newer 5G mobile communications standard. This standard is intended to be even more flexible for a wide range of applications. Some key words for the newer applications are the Internet of Things (IoT), Industry 4.0, and vehicle-to-vehicle communication for autonomous or cooperative driving. The 5G mobile communications system is intended to provide the data connection for all of these use cases. This is only possible with a massive network expansion. This will also improve communication within buildings, in particular.

[0049] As with LTE, the transmission speed of 5G depends primarily on the frequency range, the channel width, the distance to the base station (30), and the number of users within the cell. The more users simultaneously use the bandwidth, the lower the transmission rate per user. However, prioritization for paid services can be implemented, and more emphasis is being placed on Quality of Service (QoS), which allows bandwidth to be reserved for specific applications. For the 5G mobile communications system, too, reference is made to the various specifications for the precise details of the 5G standard. These can be found at www.3gpp.org.

[0050] As with LTE and 5G, OFDMA (Orthogonal Frequency Division Multiple Access) technology is used for the downlink. This technology uses the well-known multi-carrier transmission technique OFDM (Orthogonal Frequency Division Multiplexing), in which data symbols are modulated onto the individual carriers using QPSK (Quadrature Phase-Shift Keying) or QAM (Quadrature Amplitude Modulation). With OFDMA, the available frequency band is divided into many narrow bands (channels). The bandwidth is used flexibly to maximize the transmission performance of the frequencies.

[0051] Special algorithms select the appropriate channels, taking environmental influences into account. Prioritizing transmission, only those carriers that are most favorable for the user at their respective location are used.

[0052] SC-FDMA (Single Carrier Frequency Division Multiple Access) technology is used for the uplink. This is a single-carrier access method that is otherwise very similar to OFDMA. SC-FDMA exhibits lower power fluctuations and allows for simpler power amplifiers. This saves battery life, especially in mobile devices.

[0053] Uplink communication resources are also used for vehicle-to-vehicle communication.

[0054] A new frequency band will be made available for 5G in the 26 GHz range. Due to the pronounced attenuation of radio waves in the 26 GHz frequency band by the atmosphere, it is necessary to implement the corresponding 5G antennas at a distance of less than 50-100m. This is the only way to ensure sufficiently low attenuation of telecommunications signals during transmission between 5G devices and 5G antennas in rural areas with largely direct line of sight to the 5G antennas. Fig. 2 shows the distance between the 5G base stations in rural areas and the Fig. 3 the distance between 5G base stations in urban areas.

[0055] In urban areas, there is also the fact that direct line of sight between 5G antennas and telecommunications terminal devices only exists when the distance between 5G antennas is < 50-100 m from most points.

[0056] Inside buildings, however, an even higher density of 5G antennas and thus a distance of 30 - 50 m is required to achieve direct line of sight between 5G antennas and subscriber terminals (UE), see. Fig. 4.

[0057] This short distance between 5G antennas for the 26 GHz range, which is already common in telecommunications, can be used for highly accurate self-localization of subscriber stations. A particular advantage is that 5G antennas for telecommunications are actually antenna arrays with a large number of elements. Such an antenna array 310 is shown in the Fig. 5. For an element dimension of 2cm × 2cm, for example, an antenna array 310 results in Fig. 5 has a footprint of 12cm × 12cm. The reason for using such antenna arrays in 5G is that 5G is also intended to support the use of beam steering technology.

[0058] Antenna arrays with such dimensions can be easily installed in rural areas, e.g. along roads, railways and waterways, but also in urban areas as well as inside buildings and parking garages according to the Fig. 2, Fig. 3 and Fig. 4. It is more difficult to use such antenna arrays in vehicles 10 or, more generally, in mobile vehicles. However, so-called 5G single-element antennas are already available, such as those offered by the consortium of NTT DOCOMO, AGC, and Ericsson with dimensions of 1 cm × 1.5 cm. Such an element is available in the Fig. 5 also shown.

[0059] According to one aspect of the invention, such individual antenna elements are installed at multiple locations in the vehicle 10 to enable highly accurate self-localization. This is necessary for autonomous vehicles, assisted vehicles, or cooperative vehicles. Highly accurate self-localization is also required for navigation within buildings, such as parking garages.

[0060] For this purpose, the vehicles 10 are each equipped with at least one 5G single-element antenna 176 on the front, rear, and side windows of the vehicle. Each single-element antenna is connected to a transmitting and receiving unit 170 near the antenna. The transmitting and receiving unit is referred to below as a transceiver. The various transceivers are networked with each other. They are also networked with the on-board unit 110. The components and their networking are described in the Fig. 6. The installation of the transceiver 170 near the antenna is necessary in order to be able to transmit the measurement pulse, which is limited to <1 ns in time, with the required extreme edge steepness. Fig. Figure 6 shows the special form of networking in the form of a linear communication bus. A variant of the CAN bus, corresponding to a Controller Area Network, can be used as an example. The CAN bus meets the requirements regarding data rate and low latency by using the CSMA-CA bus access method, corresponding to Carrier Sense Multiple Access - Collision Avoidance.

[0061] The embedding of the antenna arrangement in the overall system of the on-board electronics is shown in the block diagram of the Fig. 7 shown.

[0062] Fig. Figure 7 shows a typical design of on-board electronics 100 of a modern motor vehicle 10, which also includes a device according to the invention for highly precise self-localization. Reference number 151 denotes an engine control unit. Reference number 152 corresponds to an ESP control unit, and reference number 153 denotes a transmission control unit. Additional control units, such as airbag control units, etc., may be present in the motor vehicle. Such control units are typically networked using the CAN (Controller Area Network) bus system 104, which is standardized as an ISO standard, ISO 11898. Since various sensors are installed in the motor vehicle and are no longer connected solely to individual control units, such sensor data is also transmitted to the individual control units via the bus system 104.Examples of sensors in a motor vehicle are wheel speed sensors, steering angle sensors, acceleration sensors, yaw rate sensors, tire pressure sensors, distance sensors, etc. The various sensors with which the vehicle is equipped are listed in the . Fig. 7 designated by the reference numbers 161, 162, 163.

[0063] However, the modern motor vehicle can also have other components such as video cameras, e.g. as a rear view camera or as a driver monitoring camera or even as a front camera to observe traffic events.

[0064] For several years now, driver assistance systems have been available that use radar, lidar, or video sensors to monitor the driving environment, interpret this sensor data, and create an internal representation of the driving situation. Based on this knowledge, they perform increasingly sophisticated functions, ranging from informing and warning the driver to specifically intervening in vehicle control. For example, longitudinal guidance on well-structured roads, such as highways, can be performed automatically for a large proportion of the time by an ACC (Adaptive Cruise Control) system equipped with lidar and / or radar sensors. With this and other measures, even fully automated vehicles can be realized.

[0065] Other electronic devices are also found in the vehicle. These are located closer to the passenger compartment and are often operated by the driver. Examples include a user interface device (not shown) that allows the driver to select driving modes, but also allows the driver to operate conventional components. These include gear selection, turn signal control, windshield wiper control, light control, etc.

[0066] This is often distinguished from a navigation system 120, which is also installed in the cockpit area. The route, which is shown on a map, can be displayed on a display in the cockpit. Reference number 110 also denotes an on-board unit. This on-board unit 110 corresponds to a communications module through which the vehicle 10 can receive and send mobile data. As described, this can be a mobile communications module, e.g., according to the 5G standard.

[0067] The devices in the passenger compartment are also interconnected via a bus system designated by reference number 102. This can be, for example, the high-speed CAN bus system according to the ISO 11898-2 standard, although here in the variant for data transmission with a higher data rate between infotainment devices. Alternatively, Ethernet is also used to network components in the vehicle. Gateway 140 is provided for the purpose of transmitting vehicle-relevant sensor data via communication module 110 to another vehicle or to another central computer. This gateway is connected to the various bus systems 102, 104. Gateway 140 is designed to convert the data it receives via CAN bus 104 into the transmission format of the high-speed CAN bus 102 so that it can be distributed in the data packets specified there.To forward this data externally, the communication module 110 is equipped to receive these data packets and convert them into the transmission format of the corresponding communication standard. To implement highly accurate self-localization, the on-board electronics are equipped with the following components: Fig. The transceivers 170 are provided at the locations shown in Figure 6, to which the antenna elements 176 are connected via a short antenna cable. In the example shown, four 5G antenna elements 176 with the associated transceivers 170 are provided. The transceivers 170 are connected to the high-speed CAN bus 102.

[0068] While driving, the individual transceivers 170 can exchange messages with the navigation system 120 and the on-board unit 110 via the CAN bus 102. The application, which is considered here as one of many exemplary embodiments, corresponds to the implementation of a highly accurate navigation system 120 that can also be used for navigation within buildings. Parking garages often have the problem that they are overcrowded, making it difficult for drivers to find a free parking space. Parking garages are often very winding and spread over several levels. This can lead to entering vehicles traveling long distances in search of a free parking space. This is a waste of resources, leads to increased emissions in the city, and also causes frustration for those looking for a parking space. An intelligent navigation system is intended to remedy this.This can receive information about the locations of available parking spaces in the parking garage via the internet connection from the parking garage's server 50. It can also download the detailed map for route guidance in the parking garage from the server 50. The navigation system 120 can then guide the vehicle 10 to the available parking space. However, this requires highly accurate self-localization.

[0069] The process of high-precision self-localization is now being carried out with the help of Fig. 8 and Fig. 9. For this purpose, the transceivers 170 are requested one after the other via the CAN bus 102 by a coordination unit 172 integrated in the on-board unit 110 to transmit the time-limited measurement pulse with a pronounced edge steepness. This measurement pulse is generated in the respective transceiver 170 using the ultra-wideband radio technology developed for short-range radio. The Federal Network Agency has currently approved several frequency ranges in the SHF range of interest here. These are ranges between 3.1 and 10.6 GHz. Also of interest is the 26 GHz range, newly approved for 5G communication, which is expected to also be approved for UWB communication in the future. The transmission power is very low at 0.5 mW / -41.3 dBm / MHz. Since this transmission power is distributed over a bandwidth of 500 MHz, interference with other radio systems is virtually non-existent. With these key data, the range is 10 - 50 m.With a distance of 30 - 50 m between the 5G base stations distributed in the parking garage, it would be necessary to design the UWB communication for a range of 50 m, which is possible by adjusting the transmission power.

[0070] Before the UWB measurement pulses can be transmitted, a defined announcement message is first sent via 5G communication to the control units of the 5G base stations with line of sight to the vehicle-side antenna elements 176. This announcement message switches the respective base station to a special operating mode in which it waits for the arrival of UWB measurement pulses from a number of antenna elements located as far apart as possible, in order to then immediately return them to the respective antenna element. Following this, the identifier of the respective base station is then additionally sent to the vehicle via a UWB pulse sequence sent directly thereafter. This is received by the antenna element 176 in the vehicle 10 from which the measurement pulse was transmitted, evaluated by the associated transceiver 170, and forwarded to the on-board unit 110 together with the measured value for the measured propagation time.In the simplest case, the individual bits of the identifier can be transmitted with the pulse sequence by sending a pulse or skipping a pulse as encoding for the bit states. Alternatively, the identifier can be transmitted following the UWB measurement via a logical channel of the mobile communications system. Both the 5G and LTE mobile communications systems offer various logical channels for this purpose. One example is the PHICH (Physical Hybrid Indicator Channel) logical channel of the 5G mobile communications system, on which acknowledgments previously sent to the base station are transmitted.

[0071] The transceiver 170 functions in such a way that, after transmitting the measurement pulse via the connected vehicle-mounted antenna 176, the transceiver 170 checks over a predetermined, limited period of time to determine the extent to which immediately returned pulses are received. If so, it determines the pulse propagation time. After assigning the identifiers of the fixed antenna array of the base station 31-35 transmitted during the response pulse transmission and the respective processing time for transmitting the response pulse after receiving the input pulse, the processing time is first subtracted from the difference between the times for transmitting the measurement pulse and receiving the response pulse, and the result is divided by two to determine the propagation time for the one-way distance. The propagation time measurement values ​​and the associated base station identifiers are then forwarded to the on-board unit 110 via the CAN bus 102.In the event of a lack of line of sight between the vehicle-mounted antenna 176 and the antenna array 310 of a fixed station 31-35, the on-board unit 110 is alternatively notified that no response pulses have arrived within the specified, limited period of time. The case of a response pulse not arriving within a limited period of time occurs when the vehicle-mounted antenna 176 is outside the reception range of the antenna array of the fixed station 31-35 and / or the antenna array 310 of the fixed station 31-35 is outside the reception range of the vehicle-mounted antenna element 176.

[0072] After receiving information from all vehicle-mounted antenna control units 170, the vehicle-mounted on-board unit 110 first estimates the distance between the vehicle-mounted antenna elements 176 and the antenna arrays 310 of the fixed stations in the reception area from the transmitted pulse propagation times. A plausibility check is then performed, taking into account the known locations of the antenna arrays 310, to identify which distance values ​​result from multiple reflections. After eliminating these distance values ​​resulting from multiple reflections, the vehicle-mounted antenna positions are subsequently calculated using trilateration or multilateration based on the remaining distance values ​​from measurements via direct line of sight. The vehicle position and / or orientation are then calculated from the calculated antenna positions on the vehicle 10.

[0073] The Fig. Figure 8 shows one level of a parking garage with many parking spaces. Filled in are some restricted areas occupied by walls, pillars, or other structural features. Distributed across the parking level are several 5G fixed stations 31–35 with their 5G antenna arrays. Due to the structural features, as well as other parked vehicles, shadowing can occur, so that the UWB measurement signals emitted by the antenna elements 176 on vehicle 10 do not have a direct line of sight to the antenna arrays of the fixed stations 31–35. This is indicated by dashed lines in Fig. 8. Thus, with a corresponding Fig. 8, the vehicle-side windshield and right-side side window antenna elements 176 have visual contact with the antenna array 310 of the fixed station 31, whereas the left-side side window antenna element 176 has no visual contact with the antenna array 310 of the fixed stations 31. Furthermore, all vehicle antenna elements 176 have no direct visual contact with the 5G fixed stations 32, 33, 34. There is also no visual contact with the fixed station 35. However, this would be the case even if there were no obstructed area in the way, because the fixed station 35 is no longer within range of the emitted pulse. Therefore, only the antenna elements 176 on the windshield and the left and right side windows will report pulse transit times, while the rear window antenna element cannot receive any reflected response pulses.

[0074] The antenna element on the left side window may report a pulse transit time, as it has no direct, but indirect, visual contact. This is in the Fig. 8 is indicated by the dashed line, which first leads from the vehicle 10 to the adjacent restricted area and from there in the direction of the antenna array of the fixed station 31. Fig. 8 shows that the propagation time measurement reported by antenna element 176 on the left side window will yield an excessively high value because the signal path is significantly longer than for the other two antenna elements 176. Therefore, a plausibility check is performed in the coordination unit 172 of the on-board unit 110. The plausibility check can be performed in one variant by comparing the pulse propagation times reported by the left and right side window antennas. A comparison is made against a tolerance value. If a measured value deviates from the measured value of antenna element 176 on the other side window by more than the specified tolerance value, the measurement is identified as faulty and discarded.

[0075] Using the remaining two antenna elements, the position and / or orientation of the vehicle is then determined using the measurement method according to the invention. When applying the measurement method according to the invention, the antenna element 176 for which no direct line of sight was identified is omitted. However, this would then result in the minimum required number of three antenna elements 176 for trilateration being undercut. To remedy this situation, the measurement method according to the invention is used for this case. The measurement is then performed again using the method according to the invention. In this case, the antenna array 310 of the fixed station is used differently. Three antenna elements are selected from the antenna array 310 that are as far apart as possible from each other. Fig. The positions of the selected antenna elements are marked in Figure 5. They are designated by reference numerals 31A, 31B, 31C. Three propagation time measurements are performed consecutively using these three antenna elements 31A, 31B, 31C. Since the positions of these three antenna elements 31A, 31B, 31C differ, the propagation times will also differ. A trilateration calculation can then be performed using the results to calculate the positions of the vehicle antenna elements 176. From this, the position and / or orientation of the vehicle 10 can then be determined. To implement the inventive method, it is necessary to initiate this operating mode. For this purpose, an announcement message is sent to the base station announcing the inventive operating mode.In order to avoid falsification of the pulse propagation times when estimating the position of these two vehicle-side antennas, it is necessary to wait for the pulse to be reflected after one of the two vehicle-side antennas has been transmitted before the next pulse is transmitted by the other of the two antennas.

[0076] The Fig. Figure 9 shows the line of sight conditions for a different position of the vehicle 10 on the illustrated parking plane. The same reference numbers denote the same components as in Fig. 8. In the Fig.In the position of the vehicle 10 shown in Figure 9, the windshield and left side window antennas have visual contact with both the antenna array of the fixed station 31 and the fixed station 32. Furthermore, the antenna array 310 of the fixed station 35 has both lateral visual contact with the rear window antenna element 176 and almost frontal visual contact with the antenna element 176 of the right side window. Thus, in this case, there is a line of sight to three different fixed stations 31, 32, 35. Two antenna elements 176 of the vehicle each have visual contact with the fixed stations. The position for each antenna element 176 can then be determined using two different trilateration calculations. An average can then be calculated between these. Averaging improves the accuracy of the position determination. The position and / or orientation of the vehicle 10 is then determined from the individual positions of the antenna elements 176 on the vehicle 10.

[0077] In summary, there are two options for determining the vehicle position and / or orientation: • Indirect estimation of the vehicle position and / or orientation according to the invention from the vehicle-side antenna element positions previously calculated by means of trilateration and, if necessary, averaged on the basis of the runtime measurements for three individual antenna elements 31A, 31B, 31C of a single antenna array. • Direct estimation of the vehicle position and / or orientation by means of trilateration based on the reflected pulse transit times of a selected antenna element 31E from three different antenna arrays distributed in space.

[0078] By implementing the two aforementioned methods and averaging the results, it can be ensured that a high degree of estimation accuracy is achieved for all vehicle positions and / or orientations. A further increase in accuracy can be achieved by weighting the results from the aforementioned methods. The weighting factors can result, for example, from a plausibility check in the form of a comparison of the determined vehicle-side antenna positions (e.g., right / left side window) and / or from taking into account the angle of incidence of reflected pulses from the stationary antenna arrays.

[0079] It should be understood that the proposed method and associated devices can be implemented in various forms of hardware, software, firmware, special-purpose processors, or a combination thereof. Special-purpose processors may include application-specific integrated circuits (ASICs), reduced instruction set computers (RISCs), and / or field-programmable gate arrays (FPGAs). Preferably, the proposed method and device are implemented as a combination of hardware and software. The software is preferably installed as an application program on a program storage device. Typically, a computer platform-based machine includes hardware such as one or more central processing units (CPUs), random access memory (RAM), and one or more input / output (I / O) interfaces. An operating system is also typically installed on the computer platform.The various processes and functions described here may be part of the application program or part of the operating system.

[0080] The disclosure is not limited to the embodiments described herein. There is room for various adaptations and modifications that a person skilled in the art would consider based on their technical knowledge and the disclosure. List of reference symbols 10 vehicles 30 - 35 fixed station 31A - 31E antenna element 5G antenna 40 Evolved Packet Core EPC 50 servers 100 Block diagram vehicle electronics 102 High-Speed ​​CAN Bus 105 Camera 104 CAN bus 110 On-Board Unit 120 navigation system 140 Gateway 151 Engine control unit 152 ESP control unit 153 Transmission control unit 161 Sensor 1 162 Sensor 2 163 Sensor 3 170 Front End 172 Coordination Unit 176 Vehicle antenna element

Claims

[1] Method for the highly accurate determination of the position and / or orientation of a vehicle (10) to be located, which is designed for communication in a wireless communication network, wherein broadband pulses of short duration are transmitted from the vehicle (10) to surrounding fixed stations (31-35), which, upon reception by the surrounding fixed stations (31-35), are answered by an immediate return of a response pulse, wherein a measurement of the propagation time of the emitted pulse until the arrival of the return pulse from at least one of the surrounding fixed stations (31-35) is carried out in the vehicle (10), wherein a respective transmission of a pulse takes place successively by a number of antenna elements (176) mounted at different positions of the vehicle (10) with respective transceivers,wherein for each mounted antenna element (176), a transceiver (170) is located near a position of the antenna element (176), and a communication module (110) is connected to the transceivers (170) of the antenna elements (176) mounted at the various positions, wherein the communication module (110) is designed to request the various transceivers (170) one after the other to transmit the broadband pulse of short duration or to assign them respective scheduled times for the successive transmission of the broadband pulses, and the time until the respective response pulse arrives at the individual antenna elements (176) is measured by means of the respective transreceiver (170),wherein the determination of the positions of the antenna elements (176) of the vehicle (10) to be located is carried out based on at least one intersection point calculation with the resulting at least three travel times and the known positions of the antennas of the fixed stations (31 - 35), and the position and / or orientation of the vehicle (10) is determined from the determined antenna element positions (176) on the vehicle (10), wherein the antennas of each fixed station (31 - 35) are designed in the form of antenna arrays (310) consisting of a number of antenna elements (31A, 31B, 31C, 31E), wherein a single antenna element (31E) is used for the return signal in order to emit the response pulse, wherein three different travel time measurements are carried out with three different individual antenna elements (31A, 31B, 31C) of the antenna array (310) are carried out one after the other, wherein the individual antenna elements (31A, 31B, 31C) are selected so thatthat they are as far apart as possible. [2] Method according to claim 1, wherein the position of the vehicle-side antenna element (176) is calculated by trilateration calculation based on the transit time measurements to the three antenna elements (31A, 31B, 31C) of the antenna array (310) of the base station (31). [3] Method according to claim 1, wherein upon arrival of the response pulses from two or more different surrounding fixed stations (31 - 35) to an antenna element (176) of the vehicle (10), an averaging of the position determinations of the antenna element (176) of the vehicle (10) to be located is carried out. [4] Method according to claim 1 or 2, wherein the transit time measurements by the various antenna elements (176) of the vehicle (10) for the pulse returned from a fixed station (31 - 35) are subjected to a plausibility check, wherein a transit time which was rejected as erroneous during the plausibility check is not used for the intersection point calculation. [5] Method according to one of the preceding claims, wherein the plausibility check is based on a comparison of the measured propagation times taking into account the local proximity of the antenna elements (176) mounted on the vehicle (10), and those propagation times are rejected as faulty whose propagation time does not correlate with the local proximity of the antenna elements (176). [6] Method according to claim 1 or 2, wherein a trilateration calculation or multilateration calculation is carried out as the intersection point calculation on the basis of the transit time measurements of an antenna element (176) attached to the vehicle (10) for the response pulses sent back from three or more different fixed stations (31 - 35). [7] Device for determining the position and / or orientation of a vehicle (10) to be located for carrying out a method according to one of claims 1 to 6, with a communication module (110) for communication in a wireless communication network with surrounding fixed stations (31 - 35), characterized bya number of antenna elements (176) mounted on the vehicle (10) at different positions, each having a transceiver (170) per mounted antenna element (176) located close to the position of the antenna element, wherein the transceiver (170) is designed to generate a broadband pulse of short duration to the surrounding fixed stations (31 - 35) and to receive a response pulse transmitted by the surrounding fixed stations (31 - 35) by direct return, wherein the respective transceiver (170) is designed to measure the propagation time of the emitted pulse until the arrival of the response pulse from one of the surrounding fixed stations (31 - 35), wherein the transmission of the pulse takes place successively by the number of antenna elements (176) and the propagation time from and to the individual antenna elements (176) on the vehicle (10) is measured separately. [8] The device according to claim 7, wherein the communication module (110) is connected to the transceivers (170) of the antenna elements (176) mounted at the different positions, and the communication module (110) is designed to request the different transceivers (170) one after the other to transmit the broadband pulse of short duration or to assign them respective scheduled times for a sequential transmission of the broadband pulses. [9] Device according to claim 7 or 8, wherein the communication module (110) is also designed for communication in a mobile radio network and is arranged to send an announcement message for the position and / or orientation determination measurement phase to the surrounding base stations (31 - 35), with which the arrival of the broadband pulse is announced and the base stations (31 - 35) are requested to answer the incoming pulse by immediately returning the response pulse. [10] Device according to claim 9, wherein the base stations (31 - 35) are requested with the announcement message to send their identification to the vehicle (10) in a further pulse or a further pulse sequence or in a logical channel of the wireless communication network following the transmission of the response pulse. [11] Device according to one of claims 7 to 10, wherein the device is arranged in a vehicle (10) and is equipped with at least one 5G single-element antenna (176) on the front, rear and side windows of the vehicle (10), each single-element antenna (176) being connected to a transmitting and receiving unit as a transceiver (170) in the vicinity of the antenna, the various transceivers being networked with one another and with an on-board unit (110) of the vehicle (10). [12] Base station for a mobile radio communication system with an antenna array (310), with a transmitting and receiving unit (320) in a building for carrying out a method according to one of claims 1 to 6 with a device in a vehicle according to one of claims 7 to 11, characterized byin that the transmitting and receiving unit (320) is designed to receive an announcement message for the position and / or orientation determination measurement phase of a vehicle (10) to be located and, in response to the receipt of the announcement message, to switch to an operating mode in which it waits for the arrival of a broadband pulse of short duration and, upon receipt of the pulse, immediately sends back a response pulse, wherein the transmitting and receiving unit (320) is designed to receive another announcement message with which the base station (31 - 35) is put into another operating mode in which it determines three antenna elements (31A, 31B, 31C) of the antenna array (310) which, for separate propagation time measurements, each sends back a response pulse to the vehicle (10) upon arrival of the broadband pulse.

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