DE102013227144A1 - Traffic communication station and method for operating a traffic communication station - Google Patents

Abstract

The traffic communication station (RSU) according to the invention is for communicating with suitably equipped vehicles (V), e.g. Road vehicles, motor vehicles, bicycles or rail vehicles. It has, according to the invention, a direction-sensitive antenna (A) and a receiving device (RX) for receiving radio signals transmitted by the vehicles (V) by means of the direction-sensitive antenna (A). Furthermore, the traffic communication station (RSU) has a detection device (EE) coupled to the receiving device (RX) for detecting a traffic topology of the vehicles (V) on the basis of the received radio signals. In addition, the traffic communication station (RSU) has an antenna controller (AS) coupled to the detection device (EE) for dynamically aligning a directional characteristic of the direction-sensitive antenna (A) as a function of the detected traffic topology.

Description

For many years it has been noticeable that traffic density is steadily increasing, especially in conurbations. As a result of this continuing trend, efficient traffic management and traffic management for road and rail transport is essential. In addition to the known control of traffic flows by e.g. Conventional traffic lights or signals are increasingly gaining in importance in traffic communication systems in which control systems associated with the traffic infrastructure communicate directly with a respective vehicle. This technique is often referred to in the art as Vehicle-to-X-Communication, abbreviated V2X. The traffic communication stations installed in traffic, e.g. A traffic light capable of communicating with vehicles is often referred to herein as roadside units, RSU for short, and their counterparts in the vehicle are referred to as onboard units, abbreviated OBUs. The RSUs and the OBUs may e.g. Transmit traffic information, status information and / or warnings in real time, e.g. to inform a driver early about a traffic jam or critical situation, or to collect traffic data from the RSU, e.g. Adjust traffic light phases to the current traffic situation. Another example of such V2X communication is the electronic detection of road tolls with RSUs mounted over highways communicating with OBUs of passing vehicles.

Usually, RSUs, such as e.g. Traffic lights or toll collection stations, normalized and permanently installed in designated places in traffic. Since the possible traffic situations and specific local conditions, e.g. With regard to road guidance, building development, radio shading, etc. have a wide range of variations, the communication range of an installed RSU, however, is reduced in many cases.

It is an object of the present invention to provide a traffic communication station with improved communication range. It is a further object of the invention to provide a method for operating a traffic communication station.

This object is achieved by a traffic communication station having the features of patent claim 1 and by a method for operating a traffic communication station having the features of patent claim 9.

The traffic communication station according to the invention is for communication with suitably equipped vehicles, e.g. Road vehicles, motor vehicles, bicycles or rail vehicles. According to the invention, the traffic communication station has a direction-sensitive antenna, such as e.g. a so-called. Phased array antenna, an antenna array or other directional antenna and a receiving device for receiving radio signals transmitted by the vehicles by means of the direction-sensitive antenna. Furthermore, the traffic communication station has a detection device coupled to the receiving device for detecting a traffic topology of the vehicles on the basis of the received radio signals. The traffic topology may include, for example, information about the road or rail topology, traffic direction, vehicle distance, traffic flow, traffic density, traffic speed, general traffic patterns or other spatial relationships or arrangements of the vehicles and the traffic infrastructure. In particular, the traffic topology can also be time-dependent. In addition, the traffic communication station has an antenna controller coupled to the detection device and the direction-sensitive antenna for dynamically aligning a directional characteristic of the direction-sensitive antenna depending on the detected traffic topology.

According to the method according to the invention for operating a traffic communication station, radio signals transmitted by the vehicles are received by means of the direction-sensitive antenna and the traffic topology is detected on the basis of the received radio signals. The directional characteristic of the directional antenna is then dynamically aligned depending on the detected traffic topology.

The directional characteristic, frequently also referred to as antenna characteristic, can in particular be oriented such that one or more main and / or side lobes of the directionally sensitive antenna are aligned with the actual and currently present traffic streams and / or directions. In this way, both the reception range and the transmission range of the direction-sensitive antenna can be significantly increased. This makes it possible to dynamically adapt the radio coverage to the current traffic and / or environmental situation even in radioically unclear terrain and in changing traffic situations. The adjustment can be done automatically during operation, so that the setup effort in the installation of the traffic communication station can be reduced. In addition, due to the improvement of the radio coverage, the transmission power and thus the power consumption of the traffic communication station can be reduced.

Advantageous embodiments and further developments of the invention are specified in the dependent claims.

According to an advantageous development of the invention, the detection device can be set up to evaluate a status message sent by a respective vehicle about a status of the vehicle and / or a transmitted location information about a location of the vehicle. The detection of the traffic topology can then take place depending on the evaluated status message and / or location information.

The location information may include, for example, the vehicle position determined by a GPS (Global Positioning System) receiver or other GPS data. From the vehicle positions received by the vehicles, the traffic communication station may obtain a map of the traffic topology, such as the traffic information. traffic flow, traffic direction, traffic density, traffic speed and / or general traffic pattern. The alignment of the directional characteristic of the directional antenna can then be done depending on the or created maps.

The status message may contain information about the current status, e.g. Speed, braking or acceleration state of the transmitting vehicle include.

Advantageously, the traffic communication station may have a learning module for detecting and recognizing patterns in the detected traffic topology. For example, certain directional, density, velocity and / or flow patterns of the traffic can be recognized, analyzed and / or learned as a pattern. The patterns may preferably be detected in their temporal variation (e.g., peak times / quiet times, day of the week / weekend), analyzed and taken into account continuously in alignment of the antenna.

According to an advantageous development of the invention, the traffic communication station may have a transmitting device for transmitting radio signals to the vehicles. In this way, the vehicles can be controlled by the traffic communication station depending on the current traffic situation or patterns detected therein. For this purpose, a traffic control can be provided in the traffic communication station.

Furthermore, by the traffic communication station, radio signals may be sent to a vehicle, the vehicle determining a quality of the received radio signals and sending a feedback on that quality to the traffic communication station. The directional characteristic of the direction-sensitive antenna can then be aligned depending on the received feedback. In this way, the traffic communication station can verify or correct the correct orientation or coverage of the directionally sensitive antenna. This is especially true in complex traffic environments, e.g. in radio shading by buildings or trees very beneficial.

An embodiment of the invention will be explained in more detail with reference to the drawing.

In each case show in a schematic representation:

1 a traffic communications station, and

2 - 6 a road junction with installed traffic communication station in different operating phases.

In 1 a traffic communication station RSU according to the invention is shown schematically. This can be, for example, a traffic light, a train signal or another roadside unit capable of communicating with vehicles and / or their OBUs in the context of V2X technology. For the present exemplary embodiment, it is assumed by way of example that the traffic communication station RSU according to the invention is installed as a traffic light at a road junction.

The traffic communication station RSU has a directional antenna A, e.g. a so-called. phased array antenna, an antenna array or other directional antenna. The directional antenna A has a directivity in both transmission and reception of radio signals, i. It can concentrate its transmission energy when transmitting and receive its reception sensitivity in one or more spatial directions and thus form predeterminable radio coverage patterns. When using an electronic phased array antenna, the directional characteristic can be controlled electronically even without mechanical movement of the antenna A in a very flexible manner. In particular, electronic control can also be used to set several preferred directions, so-called main lobes or side lobes, dynamically almost independently of one another, and thus also complex radio coverage patterns, e.g. be realized along non-rectangular road courses.

Furthermore, the traffic communication station RSU has a radio transmitter TX as a transmitting device and a radio receiver RX as a receiving device, each with the antenna A are coupled. The radio transmitter TX and the radio receiver RX serve to exchange radio signals with vehicles participating in the traffic, such as road vehicles, motor vehicles, bicycles or rail vehicles. In addition, the traffic communication station RSU contains a detection device EE coupled to the radio receiver RX for detecting a traffic topology of the vehicles on the basis of the radio signals received by the vehicles. The traffic communication station RSU further has an antenna controller AS coupled to the antenna A for dynamically aligning the directional characteristic of the antenna A as a function of the detected traffic topology. For example, based on the detected traffic topology, the directions of the traffic flows or the course of the road can be determined and different main or side lobes of the antenna A can be aligned in the determined directions.

The detection device EE in turn comprises a learning module LM for detecting and recognizing patterns in the detected traffic topology. By means of the learning module LM, the traffic communication station RSU can to a certain extent learn the direction and other parameters of the traffic flow or flows. Furthermore, the detection device EE has a matching module coupled to the radio transmitter TX and the antenna controller AS for adapting a spatial, direction-specific and / or temporal radio coverage of the antenna A to the detected traffic topology. The radio coverage may preferably be aligned with the learned traffic flows. In particular, the adaptation module AS can adapt the transmission power of the radio transmitter TX in a direction-specific manner to the detected traffic topology.

The traffic communication station RSU furthermore has a memory device DB which is coupled to the detection device EE and is implemented as a database in the present exemplary embodiment. The database DB serves to store a map MAP of the traffic topology prepared by the detection device EE. Such a database or a card stored therein is often referred to as a "neighbor table". The map MAP can be created using the learned traffic flows. Among other things, it contains information about the course of the road, here eg a road junction, about the position of the traffic communication station RSU as well as about the traffic flows and their density. In the in 1 Map MAP sketched is an example of a road junction indicated. Therein, the position of the traffic communication station RSU is illustrated by a circle and the traffic flows by arrows. While the direction of the arrows represents the direction of the traffic flows, their length may indicate, for example, the traffic flow rate and / or the length of a respective queue. In the present embodiment, the junction leads in two tracks to the cross street and in a track away from her.

Furthermore, the traffic communication station RSU has a traffic control system VS. coupled to the detection device EE and to the radio transmitter TX. The latter can have its own computing capacity for analysis, simulation and / or optimization of the traffic flow and / or be coupled to a higher-level traffic control system (not shown) which permits higher-level control, steering and / or optimization of the traffic flow (eg a "green wave"). ). The traffic controller VS may also communicate with other RSUs and / or OBUs of vehicles to analyze their traffic and / or status data and, depending thereon, to optimize the control of the traffic.

The 2 to 6 each show in a schematic representation of a road junction in a cross street with installed traffic communication station RSU in different phases of operation. By way of example, two vehicle lanes lead to the crossroads on the junction and one vehicle lane away from the crossroads. The direction of movement of the vehicles V, ie the flow of traffic is illustrated by arrows. (For reasons of clarity, only an exemplary selection of the vehicles V is provided with reference symbols.) The current radio coverage or directional characteristic of the antenna A of the traffic communication station RSU is indicated in each case by dashed lines.

2 illustrates a first phase of operation of the traffic communication station RSU. In this first operating phase, the traffic communication station RSU is in a learning mode and receives radio signals from the nearby vehicles V. In this learning mode, the antenna A is initially driven by the antenna controller AS so that its radio coverage is nearly isotropic in a substantial area of the plane , ie direction independent. This isotropic radio coverage, or directional characteristic is in 2 indicated by a dashed circle.

In the learning mode, the traffic communication station RSU continuously receives status messages as well as location information from the nearby vehicles V about their status or location. The received messages are transmitted by a respective vehicle V approximately every 100 to 500 ms. The trajectories of the vehicles V are determined from the received location information and stored in the database DB.

Alternatively or additionally, the location, the direction and / or the trajectory of the vehicles V be determined by the antenna A is at least temporarily controlled by the antenna controller AS so that it forms a pronounced directivity, so that the direction of the received signals from a respective vehicle signals can be determined.

On the basis of the determined trajectories, the traffic topology of the road junction can be determined, in particular the road or traffic course as well as the direction and speed of the traffic flows. The traffic topology is stored in the map MAP.

The determined trajectories of the vehicles V are in 3 outlined by longer arrows.

Based on the determined traffic topology, the traffic communication station RSU determines an advantageous radio coverage pattern aligned along the roadways so as to increase the radio range along the roads. By the antenna controller AS, the directional characteristic of the antenna A is set in accordance with the determined radio coverage pattern, whereby the traffic communication station RSU in a second, by 4 illustrated operating phase passes.

As in 4 indicated by dashed lines, three dominant directional lobes of the antenna A are aligned along the main roads or traffic directions and thus increase the radio communication range of the traffic communication station RSU in the direction of the traffic flows.

In a further step, the radio coverage of the antenna A can be configured as a function of a determined traffic density. For this purpose, the traffic communication station RSU determines, by means of the learning module LM on the basis of the detected traffic topology, whether and / or in which way, e.g. Make vehicle queues along the roads. Depending on this, the directional characteristic of the antenna A can be adjusted by the antenna controller AS such that one or more particularly pronounced straightening lobes are aligned with sections with a particularly high vehicle density. This can in particular be time-dependent and dynamic.

Such an orientation is in 5 outlined. The main lobe of the antenna A points in the direction of the intersecting road, which has the highest traffic density.

In the learning mode, the radio coverage can be further optimized on the basis of the continuously determined traffic topology. The traffic communication station RSU can operate for a predetermined time, e.g. remain in the learning mode for a week to then go into a normal operating mode with an aligned antenna. The transition from the learning mode to the normal operating mode can also be triggered by the fact that it is determined that the traffic topology changes only slightly. Accordingly, provision can be made for the traffic communication station RSU to return from the normal operating mode to the learning mode if it is determined that the traffic topology substantially changes.

For this purpose but also independently of this, changes in the traffic topology can be continuously recorded and evaluated. Thus, differences in traffic flows can be recorded and evaluated in each case during the rush hours and outside of it, or during the week and at weekends, depending on the road and the direction. Depending on this, the radio coverage pattern can be dynamically aligned so that as many vehicles as possible can be reached by radio and radio messages from as many vehicles as possible can be received.

The radio communication between the traffic communication station RSU and the vehicles V can be further improved by the traffic communication station RSU requesting from the vehicles V a feedback on the quality or field strength of the radio signals received by the vehicles V. On the basis of this feedback from the vehicles V, the traffic communication station RSU can then verify the radio coverage and / or modify or direct the directional characteristic so that the actual radio coverage comes as close as possible to a desired radio coverage.

6 illustrates such a feedback mechanism. As indicated by a thickened arrow running from the traffic communication station RSU to the vehicle V1, the former sends the request for a response to the vehicle V1. The vehicle V1 receives the request, measures the field strength of the radio signal of the received request, and sends back a feedback with a field strength reading, as indicated by another thickened arrow, back to the traffic communication station RSU. This can then use the received measured value as described above.

Through the feedback, the radio coverage can be adapted particularly effectively to actual or changing radio conditions, e.g. on radio shading by buildings or trees.

Claims (13)

Traffic communication station (RSU) for communication with vehicles (V), comprising a) a direction-sensitive antenna (A), b) a receiving device (RX) for receiving radio signals transmitted by the vehicles (V) by means of the direction-sensitive antenna (A), c) a detection device (EE) coupled to the receiving device (RX) for detecting a traffic topology of the vehicles (V) on the basis of the received radio signals, and d) one with the detection device (EE) and the directional antenna (A) coupled antenna control (AS) for dynamically aligning a directional characteristic of the directional antenna (A) depending on the detected traffic topology. Traffic communication station according to claim 1, characterized in that the traffic topology includes location, direction and / or time resolved data on a traffic infrastructure, a traffic flow, a traffic density, a traffic speed and / or a traffic direction of the vehicles (V). Traffic communication station according to one of the preceding claims, characterized in that the detection device (EE) is set up for evaluating a status message sent by a respective vehicle (V) about a status of the vehicle (V) and / or a transmitted location information about a location of the vehicle ( V) and for detecting the traffic topology depending on the evaluated status message and / or location information. Traffic communication station according to one of the preceding claims, characterized in that the detection device (EE) has a learning module (LM) for detecting and recognizing patterns in the detected traffic topology. Traffic communication station according to one of the preceding claims, characterized by an adaptation module (AM) for adapting a spatial, direction-specific and / or temporal radio coverage of the direction-sensitive antenna to the detected traffic topology. Traffic communication station according to one of the preceding claims, characterized by a transmitting device (TX) for transmitting radio signals to the vehicles (V). Traffic communication station according to claim 5 and 6, characterized in that the adaptation module (AM) is set up for the direction-specific adaptation of a transmission power of the transmitting device (TX) to the detected traffic topology. Traffic communication station according to Claim 6 or 7, characterized by a traffic control system (VS) coupled to the detection device (EE) and the transmission device (TX) for controlling the vehicle traffic as a function of the detected traffic topology. Method for operating a traffic communication station (RSU) for communication with vehicles (V), wherein a) radio signals transmitted by the vehicles (V) are received by means of a direction-sensitive antenna (A), b) a traffic topology of the vehicles (V) is detected on the basis of the received radio signals, and c) a directional characteristic of the direction-sensitive antenna (A) is dynamically aligned depending on the detected traffic topology. Method according to Claim 9, characterized in that status messages and / or location information transmitted by the vehicles are received by the traffic communication station (RSU), and that the traffic topology is detected as a function of the received status messages and / or the received location information. A method according to claim 9 or 10, characterized in that a direction of the received radio signals is determined by the directionally sensitive antenna (A), and that the traffic topology is detected depending on the particular direction. Method according to one of Claims 9 to 11, characterized in that radio signals are sent to a vehicle (V) by the traffic communication station (RSU), that a quality of the received radio signals is determined by the vehicle (V) and a feedback about this quality is given Traffic Communication Station (RSU) is sent, and that the directional characteristic of the direction-sensitive antenna (A) is aligned by the traffic communication station (RSU) depending on the received feedback. Method according to one of Claims 9 to 12, characterized in that the traffic communication station (RSU) is switched from a learning mode in which the traffic topology is detected to a direction-sensitive antenna (A) oriented normal operating mode.

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