DE102016224782A1 - Method and for operating a sensor device emitting a transmission signal and sensor device - Google Patents

Abstract

The invention relates to a method for operating a sensor device (102) emitting a transmission signal (106), the method comprising a step of determining a working region (116) defining a modulation of the transmission signal for the sensor device (102) using a viewing direction (118) Sensor device (102).

Description

State of the art

The invention is based on a device or a method according to the preamble of the independent claims. The subject of the present invention is also a computer program.

Several transmitters emitting in a similar spectrum may interfere with the reception of a transmitted signal from one of the transmitters. To avoid the interference, the transmitters can transmit differently modulated so that the different signals can be separated from each other.

Disclosure of the invention

Against this background, with the approach presented here, a method for operating a sensor device emitting a transmission signal, furthermore a sensor device which uses this method and finally a corresponding computer program according to the main claims are presented. The measures listed in the dependent claims advantageous refinements and improvements of the independent claim device are possible.

To avoid or reduce interference between transmitters, the viewing direction of the transmitters can be used to suitably adjust the operating ranges of the transmitters. Two transmitters moving towards each other typically have opposite viewing directions. The approach described here makes it possible to assign these transmitters, due to their different viewing directions, different work areas, by means of which interference between the transmitters is avoided.

A method for operating a sensor device emitting a transmission signal is presented, wherein the method comprises a step of determining a working range defining a modulation of the transmission signal for the sensor device using a viewing direction of the sensor device.

The transmission signal may be a sound signal, a light signal or a radio signal. A work area may for example be a frequency band of a plurality of frequency bands of a frequency range, a code of a plurality of possible codes of a code range and / or a time slot of a plurality of time slots of a transmission period. The workspace may also represent a combination of the various modulation options. The viewing direction may represent a direction with respect to a suitable approximately homogeneous field, such as the Earth's magnetic field or an artificially generated field. The viewing direction can correspond to a direction in which a maximum lies within the directional characteristic of the transmitter.

In order to determine the correct modulation or the correct working range for a single transmitter, it is no longer necessary by the described approach to search by trial and error for a free modulation mode when a new transmitter comes into range.

According to one embodiment, the transmitters transmit according to the approach presented here with a directional characteristic. A universally detectable, global variable is used as reference for at least one pre-selection of the workspace. An orientation of the transmitter relative to a reference coordinate system is used for the selection. By selecting send all the same or at least similar aligned transmitter in the same workspace. This ensures that transmitters located opposite each other transmit in different work areas and thus disturb as little as possible.

The viewing direction can be determined using a magnetic field direction of the earth's magnetic field. The magnetic field direction can be detected, for example, via an electronic compass. The magnetic field direction is independent of the viewing direction.

The viewing direction can be determined using a normal direction of gravitational force. The normal direction can be detected by a multiaxial acceleration sensor. The normal direction is independent of the viewing direction.

The viewing direction can be determined using a direction of movement of the sensor device. The direction of movement can be determined with reference to a higher-level coordinate system. The coordinate system is independent of the viewing direction.

The workspace can be determined from a group of possible workspaces. There may be a discrete number of workspaces possible. Due to the limited number, the selection can be made quickly. For example, different working directions or different viewing directions can be assigned to different work areas.

The method may include a step of transmitting the transmission signal in the work area using a transmitting unit of the sensor device and a step of receiving the Receiving signal in the work area using a receiving device of the sensor device. The method can be carried out cyclically. The transmit signal may be sent in a work area with a predefined number of repetitions before the work area is redetermined.

This method can be implemented, for example, in software or hardware or in a mixed form of software and hardware, for example in a control unit.

Furthermore, a sensor device with a transmitting unit for transmitting a transmission signal and a receiving unit, also referred to as receiving device, presented for receiving a received signal, wherein the sensor device comprises means for determining a modulation of the transmission signal defining working range for the transmission signal using a viewing direction of the sensor device ,

The sensor device according to may have an interface for reading in a direction signal representing the viewing direction. The interface may, for example, be connected to an external sensor system, such as a navigation system. The navigation system may include direction detection means for detecting a spatial direction.

The sensor device may have a direction detection device for detecting the viewing direction. The sensor device can be independent.

The direction detection device can be designed as a magnetic field sensor for detecting a magnetic field direction of the earth's magnetic field. The geomagnetic field is independent of the viewing direction.

The direction detecting means may be formed as an acceleration sensor for detecting a normal direction of gravitational force. The normal direction is independent of the viewing direction.

The approach presented here also creates a device that is designed to perform the steps of a variant of a method presented here in appropriate facilities to drive or implement. Also by this embodiment of the invention in the form of a device, the object underlying the invention can be solved quickly and efficiently.

Also of advantage is a computer program product or computer program with program code which can be stored on a machine-readable carrier or storage medium such as a semiconductor memory, a hard disk memory or an optical memory and for carrying out, implementing and / or controlling the steps of the method according to one of the embodiments described above is used, especially when the program product or program is executed on a computer or a device.

• 1 ein Blockschaltbild eines Fahrzeugs mit einer Sensorvorrichtung gemäß einem Ausführungsbeispiel;
• 2 ein Ablaufdiagramm eines Verfahrens zum Betreiben einer Sensorvorrichtung gemäß einem Ausführungsbeispiel;
• 3 eine Darstellung eines Fahrzeugs mit verschieden ausgerichteten Sensorvorrichtungen gemäß einem Ausführungsbeispiel;
• 4 eine Darstellung eines Störbereichs einer Sensorvorrichtung gemäß einem Ausführungsbeispiel;
• 5 eine Darstellung von zweidimensional verschieden ausgerichteten Arbeitsbereichen gemäß einem Ausführungsbeispiel; und
• 6 eine Darstellung von dreidimensional verschieden ausgerichteten Sensorvorrichtungen gemäß einem Ausführungsbeispiel.

Embodiments of the approach presented here are shown in the drawings and explained in more detail in the following description. It shows:

• 1 a block diagram of a vehicle with a sensor device according to an embodiment;
• 2 a flowchart of a method for operating a sensor device according to an embodiment;
• 3 a representation of a vehicle with differently oriented sensor devices according to an embodiment;
• 4 a representation of an interference region of a sensor device according to an embodiment;
• 5 a representation of two-dimensionally differently oriented workspaces according to an embodiment; and
• 6 a representation of three-dimensionally differently oriented sensor devices according to an embodiment.

In the following description of favorable embodiments of the present invention, the same or similar reference numerals are used for the elements shown in the various figures and similar acting, with a repeated description of these elements is omitted.

1 shows a block diagram of a vehicle 100 with a sensor device 102 according to an embodiment. The sensor device 102 is an active sensor and has at least one transmitter 104 for transmitting a transmission signal 106 and at least one receiver 108 for receiving a received signal 110 on. The received signal 110 is normally one by at least one object 112 in a detection area of the sensor device 102 reflected reflection of the transmission signal 106 , The transmission signal 106 and the received signal 110 are in the same frequency range. The transmission signal 106 may be, for example, a sound signal, a light signal or a radio signal. About a propagation speed and a transit time between a transmission time of the transmission signal 106 and a reception time of the reception signal 110 can be a distance between the sensor device 102 and the object 112 be calculated.

The sensor device 102 also has a facility 114 for determining a workspace 116 the sensor device 102 on. The workspace 116 becomes dependent on a viewing direction 118 the sensor device 102 certainly. The workspace 116 represents a modulation for the transmission signal 106 and a demodulation for the received signal 110 , For example, the workspace represents 116 a frequency band within the frequency range. Likewise, the workspace 116 represent a time slot within a transmission period and / or reception period. Likewise, the workspace 116 an encoding for the transmission signal 106 and a decode for the received signal 110 represent. The workspace 116 can also combine different approaches. Thus, the workspace 116 define a modulation or modulation type used for the transmit signal. A modulation type may be, for example, frequency modulation, amplitude modulation or code modulation. In a frequency modulation transmission signals 106 different sensors are modulated differently, in which the transmission signals 106 be sent out with different frequencies. In an amplitude modulation, the transmission signals 106 be differently modulated by emitting different signal amplitudes. In code modulation, the transmission signals 106 be modulated differently by coding with different codes. According to one exemplary embodiment, a working area is for each viewing direction or each sighting area 116 predetermined, which in turn is only for this work area 116 is assigned valid modulation type and / or modulation. In this way, different viewing directions or viewing direction areas are different work areas 116 each associated with different types of modulation to be used and / or modulations to be used.

The workspace 116 becomes for a controller 120 the sensor device 102 provided. The controller 120 controls the transmitting device 104 via an electrical signal 122 at. The workspace 116 is for example on the electrical signal 122 modulated or used to modulate the electrical signal 122. Likewise, the receiving device is changing 108 the received signal 110 in an electrical signal 122 that in the controller 120 using the workspace 116 is demodulated. Through modulation and demodulation, in the electrical signal 122 imaged differently modulated signal components are filtered out. In the approach presented here, in particular signal components of transmission signals of other sensor devices with other work areas are filtered out.

The device 114 For example, to determine the viewing direction uses a magnetic field direction signal 124 a magnetic field direction sensor 126 to your own line of sight 118 to determine. The magnetic field direction signal 124 In this case, a direction of a magnetic field, for example of the earth's magnetic field, is formed. The magnetic field direction sensor 126 So it can be called an electronic compass.

In one embodiment, the device uses 114 for determining a normal direction signal 128 an acceleration sensor 130 to your own line of sight 118 to determine. The normal direction signal 128 It depicts a direction of gravitational force.

In one embodiment, the device uses 114 for determining a direction signal 132 a positioning system 134 of the vehicle 100, to their own line of sight 118 to determine. This represents the direction signal 132 a momentary direction of movement of the vehicle 100 , In this case, a relative position of the sensor device 102 in the vehicle 100 considered. So if the line of sight 118 at an angle to a longitudinal axis of the vehicle 100 is aligned, the angle in the determination of the angle of view using the vehicle-related direction signal 132 considered.

In other words, an orientation-dependent dynamic coding of active sensor systems 102 presented.

Active sensors 102 that is, sensors which emit a signal 106 themselves for their measurement and from the answer 110 derive their information in the environment, are now in many mobile and stationary systems 100 common. They serve most to capture the environment of the mobile system 100 in order to realize autonomous functions or assistance functions for navigation.

Technologically, various active measurement principles can be derived, including but not limited to radar, ultrasound, lidar, flash lidar, PMD and so on and the pattern projection in conjunction with a camera, such as Kinect and so on.

Mobile platforms 100 with active sensors 102 are represented in many areas. For example, in vehicles 100 in robotics, such as intralogistics, hospital logistics or home ownership, aviation, marine and rail.

Concrete applications include, for example, a high-way assistant in the vehicle 100 with radar, a parking aid and maneuver assistance with the vehicle 100 with ultrasound and a localization in robotics by means of laser.

All conventional active sensors 102 One common problem is that of a different type of problem, depending on the technology and application.

Active sensors 102 on different mobile platforms 100 potentially interfere with each other as the sensors 102 receive the emitted signals or at least the associated reaction or reflection of the environment from other sensors and influence their own measurements. This can have different effects, from falsified measurement results, among other things ghost objects, missing objects or wrong position of the objects 112 in the environment, to a total failure of the measurement, including the complete blindness of the sensors 102 , many scenarios are conceivable.

Many solutions to this problem are possible and, depending on the technology and application, also implemented, whereby the approaches can be grouped and combined.

In a FDMA (Frequency Division Multiple Access) method, the active sensors send 102 on different frequencies, all frequencies except for the own working frequencies are suppressed.

In a Code Division Multiple Access (CDMA) method, the active sensors encode 102 their signals 106 for example, via bursts, frequency ramps, and so on, and try other codes than to suppress or filter their own.

In a TDMA (Time Division Multiple Access) method, the active sensors work 102 at different, sometimes exclusive times and so do not bother or at least less.

In an SDMA (Space Division Multiple Access), the active sensors 102 operate in different local areas.

Over the course of all approaches, a concrete selection of all possible alternatives of a procedure will be made as a work area 116 of the active sensor 102 designated. In FDMA, for example, this would be a set of operating frequencies from the set of all available frequencies, with TDMA some time ranges from the set of all possible time periods.

Mobile platforms 100 What they have in common is that they capture the same local area as they approach each other. The area around an active sensor 102 or a mobile platform 100 , which leads to a potential disturbance, is referred to hereinafter as the interference region. SDMA solutions are not possible there. The interference region can have very different dimensions depending on the application. In a high-way assistant with radar, the interference range can be about 300 m to 1000 m. In a maneuver assist with ultrasound, the disturbance range can be about 10 m to 20 m. When localized by laser, the interference range can be about 100 m to 200 m. Therefore, many other mobile platforms can be located within this fault area.

The FDMA, CDMA and TDMA solutions are from the single sensor 102 a decision is required, which concrete work area 116 So what frequency, what code or what period of time he will use. This decision depends on the other active sensors of other mobile platforms in the interference area. There are three basic approaches possible.

In a vote, the sensors tune in the interference range or beyond. This requires explicit communication between the sensors, either directly or indirectly via the mobile platform 100 or a central server. In any case, it requires a communication channel that is closed with sensor systems 102 often does not exist.

In a disturbance evaluation, the active sensors analyze their environment in a passive phase or, if possible, also during measurement operation and try to determine from possible received disturbances in which workspaces are possible other active sensors. The disadvantage here is that the passive phase costs time and it is not always robust to determine the working areas of other sensors.

With a stochastic selection, the work areas are determined stochastically. In this approach, a rare and only temporary random overlap of the work areas is hoped, whereby the active sensor would not be permanently disturbed. Together with a multiple evaluation and a large possible work area, the probability of a system-relevant disruption can thus be greatly reduced. at Multiple evaluation and longer codes are a reaction time and a hassle.

The approach presented here adds a further alternative or supplement to the determination of the work area to these procedures 116 which eliminates or at least reduces the disadvantages of the individual procedures.

Thus, according to one embodiment, a method for selecting a workspace can be 116 realize that, to some extent, guarantees that potentially disruptive active sensors 102 in different work areas 116 and thus it is only with a low probability of interference. It is an implicit vote without the need for an explicit communication channel.

The approach presented here is based on the selection of the workspace 116 depending on the absolute orientation 118 for example, with regard to an earthen or geostationary reference pole. In this case, the orientation with respect to the reference pole is synonymous with the viewing direction 118 of the sensor 102 , The orientation 118 can via a magnetic field sensor 126 or electronic compass and optionally also by means of a gravitational acceleration sensor 130 be measured and, alternatively or in addition, the orientation 118 via the input of a GPS signal 132 be determined.

The background to this idea is that there are active sensors 102 most likely to pervert environment detection when they look at each other, which is most common on oncoming mobile platforms 100 occurs. Active sensors 102 bother with the least likelihood when they look in the same direction because the mobile platforms 100 then usually drive in a row. This can be like in 4 Visualize by means of an interference area. The interference region is actually measured for ultrasound.

Although the sensors 102 No communication channel is necessary as this is implicitly the absolute orientation measured with respect to the earth-fixed coordinate system 118 he follows.

The method can be flexibly used for all applications in both FDMA, CDMA & TDMA and all technologies such as radar, ultrasound, lidar and so on.

The additional hardware requirement for measuring the absolute orientation 118 is only a small sensor, for example with combined magnetic field measurement and acceleration measurement or an input for a GPS signal 132 with known shoring on the mobile platform 100 , Both cost only a few extra cents or is on most mobile platforms 100 already installed today.

The method can be further combined with noise analysis and stochastic selection.

The disturbance evaluation can be very limited, since it is only determined whether sensors with a similar line of sight 118 and thus the same workspace 116 located in the area.

The stochastic coding is only for the case of the sensors with similar viewing direction 118 required. Since these can be calculated with much less probability of interference, the stochastic variance, such as code length, multiple evaluation and so on, can be significantly lower to obtain the same probability of occurrence of a systemically relevant disorder.

working area 116 They can be specially designed to be in the most critical situations, as if facing each other 118 , allow maximum interference suppression.

Without further knowledge of the environment, the method presented here provides a deterministic and thus modelable use of the available work areas 116 and is algorithmically very easy to implement.

components 126 . 130 or inputs for measuring the orientation 118 are required.

The approach presented here can be used with almost any active sensor principle, advantageous for applications with mobile platforms 100 because there the environment situation can not be controlled. In particular, the approach presented here is suitable for ultrasound and radar in the vehicle 100 , the railway, forklift trucks and hospital robots. In particular, the approach presented here is advantageous in forklifts which are equipped with ultrasonic arrays for person detection.

2 FIG. 12 shows a flowchart of a method for operating a sensor device according to an exemplary embodiment. The method can be used, for example, in a sensor device as shown in FIG 1 is shown executed. The method has one step 200 of determining. In step 200 In determining, a working range for the sensor device is determined using a viewing direction of the sensor device. In this case, the working area defines a modulation of a transmission signal of the sensor device.

The viewing direction can be read out from an externally provided viewing direction signal.

After the step 200 the determination is followed by a step 202 transmitting the transmission signal in the work area using the transmission unit of the sensor device. The transmission signal modulated using the work area is sent to the detection area of the sensor device. The transmission signal strikes any objects present in the detection area and is reflected at these and reflected back to the receiving device.

In one step 204 of receiving, the received signal is received in the work area.

The steps 202 . 204 The transmission and reception can be carried out several times in succession, until in a new step 200 determining an updated work area using an updated view direction.

When the viewing direction in the sensor device is detected, the step 200 of determining goes one step 206 determining, in which the viewing direction is determined, for example, using a magnetic field direction of the magnetic field of the earth.

Furthermore, in step 206 of determining a normal direction of gravitational force can be used to determine the line of sight.

In step 206 In the case of determining, the viewing direction can also be determined using a direction signal provided externally. In this case, the direction signal represents a movement direction of the platform or the vehicle to which the sensor device is connected.

In one step 208 of the suppression, a preselection of work areas can be made in the step 200 of determining can be used. The preselection can be made based on the received signal. For example, if there are gaps in the received spectrum in which the working range can be particularly advantageous, the gaps can be preselected. If time slots are free in the received signal, the free time slots can be preselected. If encodings are available in the received signal, the free encodings can be preselected.

The procedure presented here can be subdivided into several functional modules: as a preparation in a concept phase, the interpretation of the variants of the work area and the subdivision of the space of the viewing directions, and during the operation, the determination 206 the absolute orientation or the direction of the sensor and then the determination 200 a workspace for the next measurement cycle.

This in 2 The flowchart shown shows a typical sequence of an active sensor during operation. Normally, the sensor would determine its favorable working range by means of tuning, stochastic selection or fault detection and then send out the signal associated with the work area and then wait for the reactions of the environment, usually the returning reflexes. After a while, the whole cycle would start over. It is not mandatory that the workspace be re-defined in each cycle, this can also be done every two, three or four cycles. In the approach presented here, the absolute orientation is determined in the process and, based on this, the selection of the work area is modified.

The investigation 206 Absolute orientation takes place in an earth-fixed coordinate system, because this implies the agreement between the active sensors.

For example, the orientation is determined using an electric compass and for 3D of an acceleration sensor. If it is a 2D application, ie a mobile platform that moves on a horizontal surface parallel to the earth's surface, as is generally the case with robots and vehicles, an electric compass is sufficient. It measures the magnetic field of the earth and provides as an absolute earth-fixed reference pole the magnetic north pole for the horizontal orientation or the azimuth. In a 3D application can be measured with an acceleration sensor nor the acceleration of gravity to the center of mass of the earth and thus another erdfester reference pole for the vertical orientation or inclination are exploited. If both orientations are combined, it is thus possible to specify an absolute 3D orientation relative to the abovementioned earth-fixed reference poles on the spherical surface. Both measurements can be integrated compactly and inexpensively in a sensor today.

When using GPS, the absolute orientation can be measured since GPS Coordinates refer to an earth-fixed coordinate system. The absolute orientation can be obtained from a movement of the mobile platform, ie the difference between two GPS coordinates and the knowledge of their direction of movement. This information is generally provided by the parent system. This can be done for 2D and 3D applications, since GPS also provides height information in addition to the coordinates on the earth's surface with enough satellites.

For investigation 206 the viewing direction of the active sensor can be taken into account that both the orientation-measuring system and the active sensor can be installed in different positions. This positional difference can either be taken into account via the configuration or by the design documents, since the active sensor itself has internally installed this system, and thus the measured orientations are still corrected. The determination 200 the workspace is very simple. The measured viewing direction is compared with the operating points measured in the conception phase and the operating point which has the smallest deviation from it is determined. The selection can be made, for example, via the smallest internal angle of the vector from the circle / sphere center point to the operating point or measured orientation point on the circle / sphere. The work area that is assigned to the operating point determined in this way is selected as the current work mode. An operating point is a reference point within the orientation representation, such. In 2D the mean value of an angular interval or in 3D the center of gravity of a solid angle interval on the spherical surface.

If the operating point optionally contains a group of work areas, one of the group members can be selected via further additional procedures, such as stochastic selection or interference measurement.

It is particularly advantageous if the probability of occurrence of disturbances is markedly different from the front, side or back. This is true due to signal attenuation and shadowing by the mobile platform for low-range sensors such as ultrasound or flashlidar.

It is particularly advantageous if the mobile platforms are on little intersecting routes, as is the case for example extremely extremely in rail transport, but also in structured warehouses and on country roads.

3 shows a representation of a vehicle 100 with differently oriented sensor devices 102 according to an embodiment. The sensor devices 102 essentially correspond to the sensor devices in 1 , Here are all sensor devices 102 on different sides of the vehicle 100 arranged and thus have different viewing directions. The sensor devices 102 are with a positioning system 134 of the vehicle 100 connected and receive all a directional signal 132 of this. Taking into account the different orientations of the sensor devices 102 For a first sensor device, a first working area is created 116 certainly. For a second sensor device is a different second work area 300 certainly. For a third sensor device 102 a third work area 302 is determined and for a fourth sensor device 102 becomes a fourth workspace 304 certainly. Through the different work areas 116 , 300, 302, 304 are the transmission signals 106 the differently oriented sensor devices 102 differently modulated and thus clearly distinguishable from each other.

4 shows a representation of an interference region 400 a sensor device 102 according to an embodiment. The sensor device 102 corresponds essentially to the sensor device in 1 , The Störbereich 400 represents a space within which the sensor device 102 through one from another transmitter 402 . 404 . 406 equal modulated emitted transmission signal 106 and / or a reflection 110 of the transmission signal 106 on an object 112 is disturbed.

The Störbereich 400 depends on the viewing direction 118 the sensor devices 102 , One opposite to the line of sight 118 the sensor device 102 sending station 402 interferes with the reception at the sensor device 102 over a greater distance than a transmitter 404 behind the sensor device 102 in the line of sight 118 sends. A transverse to the line of sight 118 sending station 406 interferes with the reception more than the transmitter 404 behind the sensor device 102 and less than the oppositely-directed transmitter 402 ,

Here is the sturgeon area 400 for ultrasonic transmitter 402 . 404 . 406 shown. This bothers the oppositely directed transmitter 402 still in 20 meters distance. The transversely oriented transmitter 406 disturbs still ten meters away and the same aligned transmitter 402 still disturbs five meters away.

It is the sturgeon area 400 in the case of ultrasound, depending on the line of sight marked by the arrow 118 of your own active sensor 102 and other active sensors 402 . 404 . 406 shown. While in the opposite direction, the direct emitted signal very far away can still cause interference, it is at same view 118 successively arranged sensors 102 . 402 only the much less widely received reflections 110 of objects 112 , Furthermore, systems are behind the active sensor 102 additionally shaded, as the sensor 102 attached to a mobile platform or more generally to an object.

5 shows a representation of two-dimensionally differently oriented work areas 116 . 300 . 302 according to an embodiment. The workspaces 116 . 300 . 302 each extend over 120 °. The workspaces 116 . 300 . 302 have an angular offset of 120 ° to each other. This covers the three work areas 116 . 300 . 302 360 ° of a full circle. By way of example, the arrow shown on the top left represents the north direction.

6 shows a representation of three-dimensionally differently oriented work areas 116 . 300 . 302 . 304 according to an embodiment. The workspaces 116 . 300 . 302 . 304 each extend over 120 °. The workspaces 116 . 300 . 302 . 304 have an angular offset of 120 ° to each other. This covers the three work areas 116 . 300 . 302 . 304 the surface of a sphere.

An orientation subdivision or the subdivision of the viewing angles in the 2D case is shown as an example with three operating points distributed equally over the entire 360 ° space in the most favorable case. Each working point is a disjoint workspace 116 . 300 . 302 . 304 allocated. Orientations in between are always assigned to the next operating point. The dashed lines show the limits in the 2D case. in the 2D Case, at least three working points are needed for a meaningful subdivision. in the 3D Case, at least four arranged at the vertices of a tetrahedron operating points required. The orientation or the viewing angle refers to an absolute earth-fixed coordinate system, which marks north as an arrow in the 2D case.

In the conception phase, the design of the work area takes place. The design of the work area is technology-dependent and application-dependent. This embodiment is only to show the exemplary implementation possibilities. The goal is a set n of disjoint workspaces AX = A1 to AN 116 . 300 , 302, 304 interpret the sensor that do not interfere with each other or only very slightly.

An automotive radar exemplifies a maximum operating range of 75 GHz to 76 GHz. The work area can be divided into n = 10 disjoint frequency bands of approx. 100 MHz each. The frequency bands are each assigned to a work area A1 to A10. The radar system can then be operated by means of FDMA.

Ultrasound in vehicles and forklifts often sends a low-level code at the firing level, called jitter, to suppress interference. Between two shots of the sensor with a variable waiting period, it ensures that the repetition rates of two sensors do not exactly match each other. This leads to disturbances of other sensors not occurring at the same place or at the same time. A multiple evaluation only plausibilises environmental information where the same information has been received multiple times over time or place. Faults are therefore suppressed. Examples of jitter lengths are 30 ms base repeat time + k * 3 ms jitter, where k = 0 to 2 would then stand for n = 3 disjoint work areas. It is important to keep the jitter time as small as possible, as it aims directly at the reaction time of the sensor. This method represents a mixture of CDMA and TDMA.

With Lidar in robotics, the emitted light pulse can be coded by multiple pulses for interference suppression. Depending on the total pulse length and the resolution of the electronics only a limited number of individual pulses is possible. In a simple example, a maximum of three single pulses of short or long duration can be sent, that is, a 3-bit code. There are thus n = 2 ^ 3 = 8 disjoint work areas possible, the lidar would then work by means of the CDMA method.

in the 2D Case corresponds to the space of possible viewing directions a circle from 0 to 360 °, in the 3D case of a spherical surface. The spherical surface may be encoded, for example, with azimuth and inclination. You can now define as many work points as disjoint workspaces in this room 116 , 300, 302, 304 exist. in the 2D For example, at n = 4, every 90 °, an operating point on the circle can be defined, at n = 6 in the 3D case, four points every 90 ° evenly at the equator of the spherical surface and one each at the north pole and south pole. It is not absolutely necessary to distribute the operating points evenly in the space of the viewing directions. Each working point becomes a workspace 116 . 300 . 302 . 304 assigned.

It is advantageous, if there are work areas 116 . 300 . 302 . 304 are, which are particularly interference-proof to each other, for example, in the FMDA as far as possible frequency bands, the jitter as large differences in the duration and so on, these work areas 116 . 300 . 302 . 304 Assign as possible opposite operating points, since there look at the sensors each other and the probability of disturbance is highest.

Alternatively, the workspaces 116 . 300 . 302 . 304 can also be grouped into groups of equal size, for example n = 8 four groups of two work areas each. Then the groups are assigned to the work points and the work areas within a group can be used for the additional stochastic selection or the noise evaluation.

If an exemplary embodiment comprises a "and / or" link between a first feature and a second feature, then this is to be read so that the embodiment according to one embodiment, both the first feature and the second feature and according to another embodiment either only first feature or only the second feature.

Claims (13)

A method of operating a sensor device (102) emitting a transmit signal (106), the method comprising a step (200) of determining a working region (116) defining a modulation of the transmit signal for the sensor device (102) using a viewing direction (118) of the sensor device (102). Method according to Claim 1 in which the viewing direction (118) is determined in step (200) of determining using a magnetic field direction of the earth's magnetic field. A method according to any one of the preceding claims, wherein in step (200) of determining the line of sight (118) is determined using a normal direction of gravitational force. Method according to one of the preceding claims, wherein in said step (200) of determining the viewing direction (118) is determined using a direction of movement of the sensor device (102). A method according to any one of the preceding claims, wherein in step (200) of determining the work area (116) is determined from a group of possible work areas (116). Method according to one of the preceding claims, comprising a step (202) of transmitting the transmission signal (106) in the working area (116) using a transmission unit (104) of the sensor device (102) and a step (204) of receiving a reception signal (110 ) in the work area (116) using a receiving device (108) of the sensor device (102). Sensor device (102) having a transmitting unit (104) for transmitting a transmission signal (106) and a receiving unit (108) for receiving a reception signal (110), wherein the sensor device (102) comprises means (114) for determining a modulation of the transmission signal (104). 106) for the transmission signal (106) using a viewing direction (118) of the sensor device (102). Sensor device (102) according to Claim 7 , with an interface for reading in a direction signal (132) representing the viewing direction (118). Sensor device (102) according to one of the preceding claims, with a direction detection device for detecting the viewing direction (118). Sensor device (102) according to Claim 9 in which the direction detecting means is formed as a magnetic field sensor (126) for detecting a magnetic field direction of the earth's magnetic field. Sensor device (102) according to one of Claims 9 to 10 in which the direction detecting means is formed as an acceleration sensor (130) for detecting a normal direction of gravitational force. Computer program adapted to carry out the method according to one of the preceding claims. Machine-readable storage medium on which the computer program is based Claim 12 is stored.

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