EP3928119A1

EP3928119A1 - Radar sensor for factory automation and logistics automation

Info

Publication number: EP3928119A1
Application number: EP20705964.3A
Authority: EP
Inventors: Roland Welle; Daniel Schultheiss
Original assignee: Vega Grieshaber KG
Current assignee: Vega Grieshaber KG
Priority date: 2019-02-18
Filing date: 2020-02-18
Publication date: 2021-12-29
Also published as: KR20210127127A; WO2020169598A1; US20220075047A1; DE102019202144A1; CN112840223A

Abstract

The invention relates to a radar sensor for factory automation and logistics automation, comprising a radar circuit assembly, which has a radar chip for generating, emitting and evaluating radar measurement signals with an opening angle of less than 5°. The radar chip has a cross-sectional area of less than 1 cm² and generates radar measurement signals having a frequency of over 200 GHz.

Description

Radar sensor for factory and logistics automation

Reference to related applications

The present application claims the priority of German patent application No.

10 2019 202 144.1, filed February 18, 2019, in full by

Reference is incorporated into this document. Field of invention

The invention relates to factory and logistics automation. In particular, the invention relates to a radar sensor for factory and logistics automation, the use of such a radar sensor to replace an optical sensor in the field of factory and logistics

Logistics automation and the use of such a radar sensor to replace a light barrier laser sensor.

background

Optical sensors are used in factory and logistics automation to measure distance or angle values, for example. Further application examples are rotation rate transmitters or sensors for the presence detection of personnel. These optical sensors can be implemented, for example, in the form of a light barrier in order to recognize whether a person is approaching a danger area.

Summary

It is an object of the invention to provide an inexpensive alternative to known optical sensors, and in particular to light barriers. This object is achieved by the features of the independent patent claims.

Further developments of the invention emerge from the dependent claims and the following description of embodiments.

A first aspect relates to a radar sensor for factory and logistics automation. The radar sensor has a radar circuit arrangement with a radar chip, set up for generating, emitting, receiving and evaluating radar measurement signals. A housing is provided in which the radar circuit arrangement is arranged, the radar chip having a cross-sectional area of less than 1 cm ² and the generated radar measurement signals having a frequency of over 160 GHz, in particular over 200 GHz, and being focused in this way that the resulting beam opening angle is less than 5 °, or at least less than 10 °, in particular even less than 3 °.

For example, the radar chip has a cross-sectional area of less than 0.25 cm ² .

According to one embodiment of the invention, the housing has a width of 2 cm or less, a height of 5 cm or less, and a depth of 5 cm or less. The housing height runs in the measuring direction, that is, in the direction in which the radar sensor emits its measuring signal.

For example, the housing has a screw-in thread with a diameter of at most 1.91 cm or 0.75 inches. It can also be provided that the housing has a screw-in thread with a diameter of at most 1.27 cm or 0.5 inches. For example, the housing is cylindrical.

According to a further embodiment, the modulation bandwidth for the modulation of the radar measurement signals generated by the radar circuit arrangement is over 4 GHz, in particular over 10 GHz, in particular 19.5 GHz or 31.5 GHz.

According to one embodiment, the radar sensor is set up to generate and transmit an FMCW signal (Frequency Modulated Continuous Wave Signal).

According to a further embodiment, the frequencies of the generated radar measurement signals are between 231.5 GHz and 250 GHz. According to a further embodiment, the housing has a lens (or two or more lenses connected in series) which is set up to focus the emitted and / or received radar measurement signals.

The lens has, for example, a diameter of 20 mm or less than 20 mm. According to a further embodiment (as an alternative or in addition to the housing lens), the radar circuit arrangement has a (further) lens, set up to focus the emitted radar measurement signals before they strike the housing lens.

This lens has a diameter of 10 mm or less than 10 mm, for example. For example, it is placed directly on the radiator element of the radar circuit arrangement.

According to a further embodiment, the housing lens is at a distance of between 5 mm to 50 mm, in particular 30 mm or less, from the radar chip and / or the further lens. According to a further embodiment of the invention, the radar

Circuit arrangement on a radar chip with an antenna integrated therein, on which the lens is then placed, if provided.

According to a further embodiment, the radar sensor has a

Communication circuit, wherein the radar sensor is set up to detect changes in the physical measured variable that is measured by the radar sensor in real time and transmit them via the communication circuit, for example to transmit them to a remote control device.

In the context of the disclosure, “real time” is to be understood as meaning that the changes in the physical measured variable are reliably detected and transmitted within a predetermined period of time. In this context one can also use a soft one

Speak real-time requirement. The hardware and software must ensure that no unreasonable delays occur, which for example the

Could prevent compliance with the real-time condition. The data does not have to be processed as quickly as desired; however, it must be guaranteed to be fast enough for the respective application. According to a further embodiment, the radar sensor has several independent transmission / reception channels and / or several radar chips in order to provide redundancy for safety-critical applications.

According to a further embodiment, the radar sensor has a 4 to 20 mA

Two-wire interface that is set up to transmit the measured values to an external process control system and to receive the energy required to operate the radar sensor.

According to a further embodiment, the radar sensor is set up as a filling level radar. In particular, the radar sensor can have a plug connector, set up for mounting the radar sensor in an internal thread opening of a container (in which the filling material is located).

Another aspect relates to the use of a radar sensor described above and below for replacing an optical sensor in the field of factory and

Logistics automation, especially in a safety-critical area, such as the automated emergency shutdown of machines or systems.

Another aspect relates to the use of a radar sensor described above and below to replace a light barrier laser sensor.

Further embodiments of the invention are described below with reference to the figures. The representations in the figures are schematic and not to scale. If the same reference numerals are used in the following description of the figures, they denote the same or similar elements.

Brief description of the figures

1 shows a plant with radar sensors according to one embodiment. 2 shows a logistics automation system according to a further embodiment.

3 shows the use of a radar sensor in the field of factory automation and safety technology.

4 shows a radar measuring device of a sorting system. 5 shows the basic structure of a radar sensor according to an embodiment.

6 shows a further embodiment of a radar sensor.

7 shows a further embodiment of a radar sensor.

8 shows a further use of a radar sensor. Fig. 9 shows the use of a radar sensor for factory and / or

Logistics automation.

10A shows a radar sensor in a cylindrical design according to a

Embodiment.

10B shows a radar sensor in a cylindrical design according to a further embodiment.

11 shows a radar sensor in a cylindrical embodiment according to another

Embodiment.

12A shows a radar sensor with a cuboid housing.

FIG. 12B shows the radar sensor of FIG. 12A in side view. 13A shows a radar security grille according to an embodiment.

13B shows the cascaded structure of a radar safety grille from individual modules.

Detailed description of embodiments

Fig. 1 shows a plant with two radar sensors 102, 103 according to a

Embodiment. The transition to radar frequencies above 200 GHz and the integration of the antennas on the radar chip make it possible to provide a miniaturized, cost-effective measurement system that can meet all the requirements of factory and / or logistics automation and thus replace existing optical sensors with their known disadvantages .

In particular, a radar-based measuring device 102, 103 is provided which is able to measure a large part of the data previously used in the field of factory and logistics automation used to replace optical sensors. For this purpose, the measuring device can in particular be designed to provide distance or angle I values. It can also be called

Rotary rate transmitter, be designed as a sensor for presence detection or as a radar level measuring device.

Reducing the wavelength of the radar signal through the use of higher frequencies makes it possible to simplify the construction of the radar measuring device by integrating at least one primary radiator on the radar chip. So far, radar-based measurement methods could be used due to the antenna size and the

Size of the circuits are only used in the field of process automation, it will be possible in the future by using the devices proposed here to provide small and powerful radar sensors for use in the field of factory automation and / or logistics automation.

Due to the many advantages of the

Radar measurement technology has found widespread use in the field of process automation in recent years. If the term automation technology is used to mean the sub-area of technology which includes all measures for operating machines and systems without human involvement, then the sub-area of

Process automation can be understood as the lowest degree of automation. The aim of process automation is to automate the interaction of the components of an entire plant in the chemical, oil, paper, cement, shipping or mining sectors. A large number of sensors are known for this purpose, which have been adapted in particular to the specific requirements of the process industry (mechanical stability, insensitivity to contamination, extreme temperatures, extreme pressures). The measured values of these sensors are usually transmitted to a control room, in which process parameters such as level, flow, pressure or density are monitored and settings for the entire plant can be changed manually or automatically.

FIG. 1 shows an example of such a system 101. The two process measuring devices 102, 103 shown by way of example detect the fill level of the containers 104, 105 using radar signals. The recorded measured values are transmitted to a control room 108 using special communication links 106, 107. Both wired and wireless communication standards are used to transmit the measured values via the connections 106, 107, which have been optimized for the specific requirements of process measurement technology (robustness of the signal transmission against interference, large distances, low data rates, low energy density due to explosion protection requirements) .

For this reason, the measuring devices 102, 103 contain at least one

Communication unit to support process industry-compatible

Communication standards. Examples of such communication standards are purely analog standards such as the 4. 20 mA interface or digital standards such as HART, Wireless HART or PROFIBUS.

In the control room 108, the incoming data are processed by the process control system 110 and displayed visually on a monitoring system 109. The

Process control system 110 or else a user 111 can on the basis of the data

Make changes to the settings that can optimize the operation of the entire system 101. In the simplest case, when a container 104,

105 triggered a delivery order from an external supplier. Since the costs for the sensors 102, 103 in the process industry are of subordinate importance compared to the entire system 101, higher costs can be accepted for optimal implementation of the requirements such as temperature resistance or also mechanical robustness. The sensors 102, 103 therefore have expensive components such as radar antennas 112 made of stainless steel. The usual price of a process-compatible sensor 102, 103 is therefore usually in the range of several thousand euros. The previously known radar measuring devices 102, 103 of

Process industries use radar signals in the range of 6 GHz, 24 GHz or even 80 GHz for measurement, with the radar signals being frequency-modulated according to the FMCW method in the range of the center frequencies shown above. It is technically difficult to adapt the antennas 112 to higher ones that are desired in terms of measurement technology

Modulation bandwidths. Currently, using process-compatible antenna designs, 112 bandwidths up to 4 GHz can be implemented.

A completely different branch of automation technology relates to logistics automation. With the help of distance and angle sensors, processes within a building or within a single logistics system are automated in the field of logistics automation. Typical applications are systems for logistics automation in the area of baggage and freight handling at airports, in the area of traffic monitoring (toll systems), in trade, parcel distribution or in the area of building security

(Access control). What the examples listed above have in common is that one

Presence detection in combination with precise measurement of the size and position of an object is required by the respective application side. Known radar systems have so far not been able to meet the requirements here, which is why different sensors based on optical principles (laser, LED, cameras, ToF cameras) are used in the known prior art.

Figure 2 shows an example of a logistics automation system. Within a

Parcel sorting installation 201, parcels 202, 203 are to be sorted with the aid of a sorting crane 204. The packages enter the sorting system on a conveyor belt 205. With the help of one or more laser sensors 206 and / or camera sensors 206, both the position and the size of the package 203 are determined without contact, and with the help of fast data lines 207 are transmitted to a controller 208, for example a PLC 208, which is usually part of the system 201 . Since the transmission of the

Measured values over the lines 207 is time-critical, but the distances to be bridged are more in the range of a few meters, fast digital protocols such as Profinet or Ethercat are usually used as transmission standards on the communication channels 207, which in contrast to the known protocols of the

Process automation have real-time capability, i.e. a guaranteed transmission of the data in a specifiable time. This real-time capability of data transmission, which can be achieved with both wired and wireless communication standards, is the basis for controlling the sorting crane 204 via a control line 209. In contrast to known radar measuring devices, optical sensors 206 enable an exact determination of the size and position of an object 203 , since the construction of miniaturized sensors with an extremely small steel opening angle is technically not a problem in the field of optics. In addition, such systems can also be produced very cheaply compared to process measuring devices.

A third sub-area of automation technology relates to factory automation.

Use cases for this can be found in a wide variety of industries such as

Automobile production, food production, pharmaceutical industry or in general in the field of packaging. The aim of factory automation is to automate the production of goods using machines, production lines and / or robots, ie without the involvement of the Let people run off. The sensors used here and specific requirements with regard to the measurement accuracy when recording the position and size of an object are comparable to those in the previous example of logistics automation. Therefore, sensors based on optical measuring methods are usually used on a large scale in the field of factory automation.

Another area of application for optical sensors relates to security technology, which has both applications in the field of logistics automation and in the field of

Factory automation includes. Figure 3 shows a corresponding example. As soon as human interaction is to be expected in the area of fully or semi-automatic production or sorting systems, the legislature provides for the installation of suitable protective devices for the automated shutdown of machines and systems. In the present example, the punching machine 301 punches round shaped parts 302 from a sheet metal material 303. A worker 304 is responsible for overseeing the process. So that the worker cannot injure himself when intervening in the machine 301, the machine 301 has a safety light barrier 305 or a

Safety light curtain 305, which is connected to machine 301 via a communication line 306. The safety light barrier 305 measures the distance d1, d2 to the underlying object, and can prevent a lowering of the stamp 307 both in the absence of a sheet metal 303 and in the event of an unintentional intervention by the user 304 in the stamp area. One of the basic requirements for the safe operation of the system is that the sensor 305 can determine the distance with a high degree of accuracy and reliability in conjunction with an extremely short measuring time

Reliably recognize dangerous situations.

Optical sensors have dominated both in the field of logistics automation and in the field of factory automation and security technology. These are quick and inexpensive and can reliably determine the position and / or the distance to an object on the basis of the relatively easy-to-focus optical radiation on which the measurement is based. A significant disadvantage of optical sensors, however, is their increased need for maintenance, since even in the areas listed above, after a few thousand hours of operation, the sensor becomes soiled, which has a massive impact on the measurement. In addition, especially when used in production lines, the measurement can be impaired by oil vapors or other aerosols with fog formation and lead to additional contamination of optical sensors. The aforementioned disadvantages can be overcome by using radar-based measuring devices. Before the embodiments are discussed in detail, FIG. 4 once again summarizes the problems to be solved by the present disclosure.

If a known radar measuring device 102 were installed, for example, in a sorting system 201 instead of an optical sensor 206, its radar signal 401, due to the large opening angle 402 of typically 8 ° or more, simultaneously detects both packages 202, 203 located on the conveyor belt 205 at a distance of a few meters. The detected reflections of the packets are converted into an echo curve 403 by the radar measuring device 102 according to known methods. Is the radar measuring device 102 working?

for example with a frequency of 23.5 GHz to 24.5 GHz, the width dRR 404 of a single echo 405 is already 15 cm. If the distance dP 406 between the two packets 202, 203 is less than the radar resolution 404 of the measuring device 102, it can no longer be recognized by measurement technology that two packets are involved. It should be noted that this problem arises from the widened detection range 402 in combination with the reduced radar resolution 404. Ultimately, even if the aforementioned problems were neglected, the use of the radar measuring device 102 in the sorting system would fail at the latest because the communication device 407 of the measuring device 102 is not able to transmit the measured value via the

To transmit communication channel 410 in real time. The above-mentioned disadvantages come to light in the same way when trying to use it in the field of security technology (FIG. 3). The radar sensors described above and below represent a high

Radar resolution and very good beam focusing in conjunction with a

real-time capable communication device in miniaturized design at a moderate price. FIG. 5 shows the basic structure of a radar system which is suitable for use in factory and / or logistics automation or security technology. The radar measuring device 501 has a housing 510 which contains a communication unit 502, a processor 504 and a high-frequency unit 505. The

High-frequency unit 505 has at least one integrated radar chip 506 which can generate and emit high-frequency signals with a frequency of more than 200 GHz. The radar signals penetrate the housing of the radar sensor 501 at one predefined location 507, the housing of the sensor 501 being designed to be penetrable at least in the area of penetration for electromagnetic waves above 200 GHz. The radar signals 508 are focused by focusing elements or lenses 512, 513 on the integrated radar chip 506 and / or in the area of the penetration 507 and / or in the area between the radar chip and the penetration in such a way that the resulting beam opening angle 509 becomes very small, for example smaller than 5 °. The measured values determined by the measuring device are transmitted via a wired or wireless data transmission channel 503 at a high data rate to a local switch cabinet 208 or a machine 301. It can optionally be provided this

To carry out data transmission in such a way that it is real-time capable, and thus to achieve the timely influencing, for example, of a production line or a sorting device or also the timely switching off of a machine before endangering a person. Standards such as Profinet, Power over Ethernet, Ethernet, Ethercat or IO-Link can be used here.

Figure 6 shows a further embodiment of the sensor 501 in detail. Of the

Microprocessor 504 controls a PLL 601 dividing whole numbers or preferably fractional numbers. The PLL, in turn, is connected to a voltage-controlled oscillator 602, which, in conjunction with the PLL, outputs a frequency-modulated signal at its output 603 with a center frequency in the range from 10 GHz to 60 GHz and a bandwidth between 5 GHz and 10 GHz. The parameters mentioned above can be changed during the operating phase of the measuring device. The signal 603 generated by the VCO is fed to a frequency converter 604, which the

Converts the input signal into a target frequency range greater than 200GHz. Usually several implementation steps are carried out in a cascade, i.e. the signal is increased in frequency over at least two sub-steps by doubling circuits.

However, provision can also be made for the signal in the frequency converter to be transmitted to the target frequency range above 200 GHz by mixing in one or more stages. The resulting signal 605 is preferably in a range above 200 GHz; frequencies in the range between 230 GHz and 250 GHz have proven particularly advantageous. The signal is then fed to a divider module 606, whereupon some of the high-frequency signals are radiated outwards via a primary radiator 607 in the direction of the penetration 507. With the aid of a receiving antenna 608, the radar signals reflected in the respective application are recorded again, and in one

Mixer module 609 implemented in a low-frequency range. The analog filter 610 and the analog-to-digital converter 611 capture the signals and pass them on to further

Processing to processor 504.

A core concept of the present disclosure is that an increased radar resolution 404 can only be achieved by reducing the width of the echoes 405. By a

Increasing the modulation bandwidth to more than 4 GHz, preferably more than 10 GHz or particularly advantageously to 19.5 GHz, the result can be that the width of the echoes can be reduced to the millimeter range. This means that reflectors 202, 203 that are close to one another, as can occur in factory and logistics automation, can be reliably detected by measurement. In terms of circuitry, the implementation of these increased modulation bandwidths can only be managed inexpensively if the

Fundamental frequency of the radar signal is high, preferably above 200 GHz. Since the wavelength of the radar signals on a semiconductor chip then also moves into the millimeter or sub-millimeter range, common designs for coupler structures or the primary radiator 607 or the receiving antenna 608 can be implemented directly on the semiconductor substrate 612 of the integrated radar chip 613, which enables a cost-effective structure. In addition, it can be provided that the radiated or received radar signals are bundled in the area of the antennas 607, 608 by means of beam-influencing lens elements 614, 615 in order to achieve a reduced opening angle 509 of the radar signals.

Figure 7 shows a further embodiment of a radar device for use in factory and / or logistics automation or security technology. The proposed measuring device 701 differs from the structure presented above by the use of a combined transmitting and receiving antenna 703, which due to the high

Working frequency of more than 200 GHz is preferably implemented on the semiconductor substrate 612 of the integrated radar chip. An additional transmission / reception switch 702, which is also integrated on the chip 612, is used to separate the signals. Optionally, in this case too, the opening angle 509 of the measuring device can be reduced if a lens element 704 influencing the beam is applied directly to the chip in the area of the primary radiator 703. In the present example, provision is also made for the PLL 601, the ADC 611 and the analog filter 610 to be integrated into the radar chip 705, for example by bonding the different ones

Assemblies in a common package 705. Provision can also be made for the aforementioned assemblies to be integrated directly on a single semiconductor substrate 612. The The last-mentioned embodiments lead to a drastic reduction in the costs of building such a system.

Figure 8 illustrates the advantages when used in the field of security technology. The radar measuring device 701 with the aforementioned features monitors the danger area below the punching machine 301. Due to the extremely high radar resolution of a few millimeters, it is now possible for the first time to have a corresponding reflection 801 in the area recorded by the measuring device 701 when a hand of the user 304 penetrates the danger area To capture echo curve 803, and this safely from the reflection 802 of the

To distinguish sheet material 303. The measuring device 701 can in a further

Embodiment through implementation of a suitable safety function,

for example in the processor 704, be equipped in such a way that it monitors at least one parameterizable danger area SAFE 804, and when an object is detected in the area, a targeted, real-time-critical safety reaction is triggered. This can be done by transmitting a corresponding signal via the communication device 503 directly to the machine. However, it can also be provided to integrate corresponding switching elements, for example positively driven relays, directly in the measuring device 701. Depending on the security level to be achieved, provision can also be made for the radar measurement to be carried out redundantly with multiple channels, for example by installing several radar chips in the measuring device 701.

FIG. 9 shows the use of a measuring device described above for factory and / or logistics automation. By using at least two focusing elements 904, 905, the radar signal generated by the measuring device 503 is focused in such a way that it has an opening angle 509 of a few degrees. This enables the device, through appropriate alignment, to determine the exact position of a package 203 along its beam direction 510. By using several sensors 701 or by using beam-deflecting elements, an extended area of the conveyor belt 205 can also be monitored and the position and location of the packages 202, 203 can be precisely determined. Via the fast, real-time

Communication device 503, a sorting system can be controlled efficiently. Due to the high radar resolution of a few millimeters, the echo curve 901 recorded by the measuring device 701 can reliably separate the reflected signals 902, 903 even from closely spaced packets 202, 203. 10A shows a radar sensor 1000 with a cylindrical housing. At the rear end of the housing 1001, an electrical connection is provided, for example for

Connection to a 4 to 20 mA two-wire line or to an IO-Link interface, the connector of which is screwed onto the rear end of the housing, for example. The middle part of the housing 510 has a screw-in hexagon 513, to which a screw-in stop 514 is connected, followed by a screw-in thread 511 for screwing into a holder or the opening of a container. The screw thread 511 has a diameter of one-half inch or less. in the

Screw-in thread can for example be a radar lens and / or the antenna for emitting / receiving the measurement signals.

The length (or “height”) of the housing is typically a maximum of 100 mm.

The embodiment of FIG. 10B corresponds in many respects to that of FIG. 10A. However, the screw-in thread 511 is located in the middle area of the housing 510, followed by the stop 514 and the screw-in hexagon 513. In the embodiment according to FIG. 11, a screw-in thread 511 is also provided in the middle area of the housing 510, the diameter of the housing <22 mm. It can be provided that the radar sensor according to FIG. 11 directly into a

To screw in the thread mount of a machine and secure it with a lock nut. However, provision can also be made for the radar sensor to be screwed into a threaded receptacle of a machine that forms a blind hole. In the installed state, the front end of the sensor 511 in the area of the radar lens lies flat against a bottom surface of the blind hole of the machine that is permeable to microwave signals. By tightening the sensor in the blind hole, secure fastening can be achieved by bracing it against the floor surface. It can be provided that the sensor 511 has a hexagonal receptacle in order to simplify the tightening.

12A shows a radar sensor 1200 with a cuboid housing 510. The height of the housing is 5 cm, the width 2 cm and the depth likewise 5 cm. A lens 513 is arranged in the front area of the housing. An electrical connection 1201 is located in the lower area. The housing consists for example of polyethylene or polypropylene. 13A shows what is known as a radar safety grid 1300, which has a multiplicity of radar chips 506, 1301 to 1305. Each radar chip has its own first lens 512, which is arranged in the region of the emitter element, and a “housing” lens 513, which is arranged in the beam path of the first lens. The large number of radar chips provides redundancy, which can be advantageous in particular for safety-critical applications.

13B shows a cascaded structure of a radar sensor from individual modules. In this embodiment, each individual module has two radar chips 506, 1301 or 1302, 1303, each with a first lens 512 and a second lens 513 in the

Housing wall. Each module has an input interface 1305 and a

Output interface 1306, via which the modules can be electronically connected to one another.

With the described embodiments, it is possible for the first time to replace optical measurement methods in the field of factory automation, logistics automation and safety technology with radar-based measured value acquisition, and thus in particular because of the inherent insensitivity to radar measurement technology

Reduce the maintenance effort. By transitioning to

Frequencies above 200GHz can also significantly reduce the size and cost of the sensors, thus providing an adequate replacement for optical sensors.

In addition, it should be noted that “comprising” and “having” do not exclude any other elements or steps and the indefinite articles “a” or “a” do not exclude a multiplicity. Furthermore, it should be pointed out that features or steps that have been described with reference to one of the above exemplary embodiments, also in combination with other features or steps of others described above

Embodiments can be used. Reference signs in the claims are not to be regarded as restrictions.

Claims

1. Radar sensor (100, 102, 103, 501, 701, 1000, 1100, 1200) for the factory and

Logistics automation, comprising:

a radar circuit arrangement (505) with a radar chip (506), set up for

Generation, transmission, reception and evaluation of radar measurement signals;

a housing (510) in which the radar circuitry is arranged and wherein the radar chip has a cross-sectional area of less than 1 cm ² ;

wherein the radar measurement signals have a frequency of over 160 GHz and are focused in such a way that the resulting beam opening angle is less than 5 °.

2. Radar sensor (100, 102, 103, 501, 701, 1000, 1100, 1200) according to claim 1,

wherein the radar chip (506) has a cross-sectional area of less than 0.25 cm ² .

3. Radar sensor (100, 102, 103, 501, 701, 1000, 1100, 1200) according to claim 1 or 2, wherein the housing (510) has a width of a maximum of 2 cm, a height of a maximum of 5 cm and a depth of a maximum of 5 cm cm.

4. Radar sensor (100, 102, 103, 501, 701, 1000, 1100, 1200) according to one of the

preceding claims,

wherein the housing (510) has a screw-in thread (511) with a diameter of at most 1.91 cm or 0.75 inches. 5. Radar sensor (100, 102, 103, 501, 701, 1000, 1100, 1200) according to one of the

preceding claims,

the modulation bandwidth for the modulation of the radar measurement signals generated by the radar circuit arrangement (505) at over 4 GHz, in particular at over 10 GHz, in particular at 19.5 GHz or 31,

5 GHz.

6. Radar sensor (100, 102, 103, 501, 701, 1000, 1100, 1200) according to one of the

preceding claims,

whereby the frequencies of the generated radar measurement signals are between 231.5 GHz and 250 GHz.

7. Radar sensor (100, 102, 103, 501, 701, 1000, 1 100, 1200) according to one of the

preceding claims,

wherein the housing (510) has a lens (507) configured to focus the radar measurement signals emitted.

8. radar sensor (100, 102, 103, 501, 701, 1000, 1 100, 1200) according to claim 7,

wherein the lens (507) has a diameter of 20 mm or less.

9. Radar sensor (100, 102, 103, 501, 701, 1000, 1 100, 1200) according to one of the

preceding claims,

wherein the radar circuit arrangement (505) has a lens (512) set up to focus the radar measurement signals emitted.

10. Radar sensor (100, 102, 103, 501, 701, 1000, 1 100, 1200) according to claim 9,

wherein the lens (512) has a diameter of 10 mm or less.

1 1. Radar sensor (100, 102, 103, 501, 701, 1000, 1 100, 1200) according to Claim 9 or 10, wherein the lens (512) is at a distance of between 5 mm to 50 mm, in particular 30 mm or less, from the radar chip (506 ) and / or the lens (507).

12. Radar sensor (100, 102, 103, 501, 701, 1000, 1 100, 1200) according to one of the

preceding claims,

wherein the radar circuit arrangement (505) has a radar chip (612) with an antenna (607) integrated therein.

13. Radar sensor (100, 102, 103, 501, 701, 1000, 1 100, 1200) according to one of the

preceding claims,

having a communication circuit (502),

wherein the radar sensor is set up to detect changes in the physical measured variable in real time, that is to say reliably within a predetermined time span, and to transmit them via the communication circuit.

14. Radar sensor (100, 102, 103, 501, 701, 1000, 1 100, 1200) according to one of the

preceding claims, wherein the radar sensor has multiple independent transmit / receive channels and / or multiple radar chips (506, 1301, 1302, 1303, 1304, 1305, 1306) to a

Providing redundancy for safety-critical applications.

15. Radar sensor (100, 102, 103, 501, 701, 1000, 1 100, 1200) according to one of the

preceding claims, comprising:

a 4-20 mA two-wire interface (106), set up to transmit the measured values to an external process control system (1 10) and to receive the energy required to operate the radar sensor.

16. Radar sensor (100, 102, 103, 501, 701, 1000, 1 100, 1200) according to one of the

preceding claims, set up as level radar.

17. Radar sensor (100, 102, 103, 501, 701, 1000, 1 100, 1200) according to one of the

The preceding claims, comprising a plug connector (51 1, 513, 514), set up for mounting the radar sensor in an opening of a container provided with an internal thread.

18. Use of a radar sensor (100, 102, 103, 501, 701, 1000, 1 100, 1200) according to one of claims 1 to 17 for replacing an optical sensor in the field of factory and logistics automation, in particular in a safety-critical area such as the automated emergency shutdown of machines or systems.

19. Use of a radar sensor (100, 102, 103, 501, 701, 1000, 1 100, 1200) according to one of claims 1 to 17 to replace a light barrier laser sensor.