Radar measuring device

Abstract

A radar measuring device for process automation in an industrial or private environment has a control unit for calculating an average transmission power of radar measurement signals to be transmitted during a measurement interval, and divide the measurement interval into a plurality of consecutive partial measurement intervals when the calculated average transmit power is greater than a predetermined threshold power.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to process automation in industrial or private environments. In particular, the present disclosure relates to a radar measuring device for process automation in industrial or private environments, a use of the radar measuring device, a method for measuring with the radar measuring device, a program product and a computer-readable medium. BACKGROUND

[0002] In the case of a radar measuring device for process automation in industrial or private environments, in particular in level measurement technology and in production automation, it is noted that the average radio frequency transmission power emitted by the radar measuring device should not exceed a prescribed threshold power. In particular, the average transmission power emitted by the radar measuring device during a measurement interval can play a decisive role here.

[0003] In order to adjust the transmission power, the user can reduce the transmission power depending on the place of use of the radar measuring device. SUMMARY

[0004] It is an object of the present disclosure to provide a radar measuring device which does not exceed a maximum predetermined transmission power on a time average.

[0005] This object is solved by the features of the independent claims. Improvements of the invention emerge from the dependent claims and the description of the following embodiments.

[0006] A first aspect of the present disclosure relates to a radar measuring device configured for process automation in industrial or private environments. In particular, the radar measuring device comprises a control unit configured to calculate an average transmission power of a radar measuring signal to be transmitted during a measurement interval.

[0007] The control unit is configured to compare the calculated average transmission power with a predetermined threshold power and then, if the calculated average transmission power is greater than the predetermined threshold power, to divide the measurement interval into a plurality of consecutive partial measurement intervals (partial scans).

[0008] The consecutive partial measurement intervals are separated from one another by measurement pauses in order to reduce the average transmission power of the radar measuring signal to be transmitted so that it falls below the predetermined threshold.

[0009] The term "measurement interval" is to be understood as the time interval in which a measurement cycle is carried out, for example in the form of a frequency sweep or more precisely a frequency run-through in the case of a frequency-modulated continuous wave (FMCW) radar measuring device. Thus, in the case of a pulsed radar measuring signal, the measurement interval corresponds to the time interval between the emission and the re-reception of a radar pulse.

[0010] Once the measurement interval has been completed, the echo curve is recorded, for example, from which the level can be calculated.

[0011] The average transmission power (calculated) corresponds to the average transmission power of the radar measurement signals transmitted during the measurement interval.

[0012] In other words, a measurement is broken down into a plurality of partial measurements, which can then be recombined into a complete measurement using software.

[0013] The division into a plurality of successive partial measurement intervals or partial scans can depend on national requirements, which can be determined independently by the radar measurement device, if necessary by means of a database query in data stored in the cloud or in the radar measurement device, using GPS and / or land parameter input. The radar measurement device can be configured to do this independently and determine the partial measurement intervals itself. For this purpose, artificial intelligence can be used.

[0014] The radar measurement device can be connected to a 4..20 mA power supply ("loop"). In particular, the radar measurement device can be powered exclusively by this loop.

[0015] In particular, the radar measurement device can also be designed as a battery-powered sensor. In this case, the prevailing radio license can also require the procedure in the case of the scan division.

[0016] According to an embodiment of the application, the radar measurement device comprises a radar module, which is configured to generate and transmit radar measurement signals during successive partial measurement intervals.

[0017] In particular, the radar measurement device can be designed as an FMCW radar measurement device.

[0018] In the case of an FMCW radar measurement device, it is usually not possible or must be achieved with considerable effort to perform a frequency scan (frequency traversal) in such a short time that even at the maximum possible transmission power, the regulations for the maximum permissible average transmission power are met.

[0019] However, as mentioned above, the frequency scan can also be performed in such a way that the requirements for the maximum permissible average radio frequency transmission power are met. Depending on the maximum possible transmission power of the radar measurement signals to be transmitted, the average power is correspondingly reduced by appropriate measures (mitigation techniques).

[0020] This is achieved by dividing the frequency scan into a plurality of short sections (partial scans or partial measurement intervals) which can then be recombined into a complete scan using software.

[0021] According to an embodiment, the control unit is configured to determine the number of partial measurement intervals depending on the size of the frequency deviation of the entire frequency traversal of the measurement interval and / or depending on the maximum transmission power of the radar measurement signal to be transmitted when the measurement interval is divided into a plurality of consecutive partial measurement intervals.

[0022] According to another embodiment of the present application, the control unit is configured to determine the length of the measurement pause between consecutive partial measurement intervals depending on the size of the frequency deviation of the entire frequency traversal of the measurement interval and / or depending on the maximum transmission power of the radar measurement signal to be transmitted when the measurement interval is divided into a plurality of consecutive partial measurement intervals.

[0023] According to another embodiment of the present application, the control unit is configured to reduce the slope of the frequency ramp of the frequency traversal when the measurement interval is divided into a plurality of consecutive partial measurement intervals.

[0024] Depending on the size of the frequency scan, it can be divided into different numbers of partial scans in order to meet the requirements of the maximum possible average radio frequency output power and to make appropriate pauses between the partial scans.

[0025] The advantage of this approach is that the partial scans can also be performed with a lower slope of the ramp. This means that radar systems with relatively slow AD converters, more points (i.e. a large number of samples) and thus longer scan times can also be implemented.

[0026] Another advantage is that for short scans or partial scans, the size of the energy store (e.g. storage capacitor) required in the radar measurement device can be smaller.

[0027] The division of the scan into a plurality of consecutive partial measurement intervals also has advantages for overall power management, since the load jumps become smaller or shorter and can be controlled or reacted to more precisely.

[0028] According to another embodiment of the present application, the radar measurement device is designed such that no radar measurement signal is transmitted during the measurement pause between consecutive partial measurement intervals.

[0029] According to another embodiment of the present application, the control unit is configured to perform the frequency traversal more quickly and at the same time to increase the sampling frequency of the radar measurement signal when the calculated average transmission power is greater than a predetermined threshold power.

[0030] To reduce the average transmit power, several precautions can be taken; on the one hand, the measurement interval is split into successive partial measurement intervals, which are separated from one another in time by a corresponding measurement pause; on the other hand, the traversal speed of the frequency ramp is accelerated and at the same time the sampling frequency of the radar measurement signal is increased.

[0031] According to a further embodiment of the application, the maximum transmit power of the radar measurement signal to be transmitted does not change even if the measurement interval is divided into a plurality of successive partial measurement intervals.

[0032] The "maximum transmit power of the radar measurement signal to be transmitted" is the maximum value of the transmit power to be transmitted. In an ideal case, the transmit power does not fluctuate with the frequency ramp. However, in the case of many radar circuits, the output power can be influenced by means of a controllable amplifier. Depending on the application, the antenna used or the radio approval standards, the transmit power can be adjusted in its entirety (to the same value over the entire frequency ramp).

[0033] A further aspect of the present disclosure relates to the use of the above and below described radar measurement device for level measurement and object detection, for example for object detection when monitoring a work area.

[0034] A further aspect of the present disclosure relates to a method for measuring with a radar measurement device for process automation in an industrial or private environment. First, the average transmit power of the radar measurement signal to be transmitted during the measurement interval is calculated, and then the calculated average transmit power is compared with a predetermined threshold power. If the calculated average transmit power is greater than the predetermined threshold power, the measurement interval is divided into two or more successive partial measurement intervals, which are separated from one another by a measurement pause, in order to reduce the average transmit power of the radar measurement signal to be transmitted so that it is reduced below the predetermined threshold.

[0035] A further aspect of the present disclosure relates to a program product which, when executed on a control unit of a radar measurement device, instructs the radar measurement device to carry out the above and below described steps.

[0036] A further aspect of the present disclosure relates to a computer-readable medium which stores the above described program product.

[0037] Process automation in the industrial context can be understood as a branch of technology encompassing all measures for operating machines and plants without human intervention. One of the goals of process automation is to automate the interactions between the various components in plants for the chemical, food, pharmaceutical, oil, paper, cement, shipping, or mining industries. To this end, a wide range of sensors can be used, which are specifically tailored to the specific requirements of the process industry, such as mechanical stability and insensitivity to contamination, extreme temperatures, and pressures. The measured values ​​from these sensors are typically transmitted to a control room, where process parameters such as fill level, limit level, flow rate, pressure, or density can be monitored, and plant-wide settings can be modified manually or automatically.

[0038] A subfield of process automation in industrial environments involves the automation of factory logistics and supply chain logistics. In the field of logistics automation, distance and angle sensors are used to automate processes within buildings or within individual logistics systems. Typical applications for logistics automation systems include: airport baggage and freight handling, traffic monitoring (toll collection systems), retail, parcel delivery or building security (access control). What the above examples have in common is that each application requires the combination of presence detection with the precise measurement of the size and position of an object. Sensors based on optical measurement methods using lasers, LEDs, 2D cameras or 3D cameras can be used for this purpose, which measure distances according to the time-of-flight principle (ToF).

[0039] Another subfield of process automation within the industrial environment involves factory / manufacturing automation. Application examples can be found in a variety of industries, such as automotive manufacturing, food production, the pharmaceutical industry, and general packaging. The goal of factory automation is to automate the production of goods using machines, production lines, and / or robots—that is, to operate without human intervention. The specific requirements for sensors used here and the measurement accuracy required to detect the position and size of objects are comparable to those in the previous example of logistics automation.

[0040] In interpreting the terms used in the claims, these terms should be construed in accordance with the broadest reasonable interpretation available. For example, the articles "a" and "the" as used in the description should not be construed as excluding plural references unless context clearly indicates otherwise. Similarly, the term "or" as used in the context of a list of items prefaced by that term should be construed in the broadest sense as encompassing one or more of the items succeeding the term. Also, the term "comprising" does not exclude the presence of elements or steps other than those listed in a claim or listed in the summary of the application. Further, the terms "first," "second," and the like as used in the description should not be construed as excluding the presence of more than one element having the given reference numeral. Also, the use of relative terms such as "about," "approximately," "substantially" and the like are intended to convey that the term so described encompasses minor variations (plus or minus ten percent) from the point of reference. Finally, the terms "coupled" and "connected" as used in the description include an electrical or mechanical connection between referenced entities.

[0041] Other embodiments of the present disclosure are explained below with reference to the drawings. The drawings in the figures are only schematic, and they are not drawn on scale. Identical components have been given the same reference numerals in the figures. BRIEF DESCRIPTION OF DRAWINGS

[0042] Figure 1 A frequency sweep is shown split into several partial frequency sweeps.

[0043] Figure 2 Another example of such a split is shown.

[0044] Figure 3 Yet another example of such a split is shown.

[0045] Figure 4 A radar measurement device according to an embodiment of the present disclosure is shown.

[0046] Figure 5 A flowchart of a method according to an embodiment of the present disclosure is shown. DETAILED DESCRIPTION

[0047] Figure 1 On the left a frequency traversal (frequency sweep) is shown, which shows the frequency of the radar measurement signal transmitted by the radar measurement device over time.

[0048] In the so-called off-range, no radar measurement signal is present on the radar measurement signal antenna. In the subsequent radio frequency on-range (HF-ON-Bereich), the measurement begins and the radar measurement signal to be emitted increases linearly over time from a start frequency to an end frequency. In this context, the so-called frequency ramp traversed is also spoken of. At the end of the frequency ramp, the frequency scan stops and the off-phase begins again, during which the antenna does not emit a signal.

[0049] In Figure 1 The right side shows how this frequency ramp can be divided into several partial frequency ramps or partial measurement intervals, which are separated from one another by off-phases. During these off-phases, also referred to as measurement pauses, no radar measurement signal is emitted.

[0050] In other words, the frequency scan is divided into a plurality of partial scans. For example, an 8 GHz scan with a scan time of 2 milliseconds is divided into four partial scans. Thus, a partial scan lasts 0.5 milliseconds, followed by a pause of 0.5 milliseconds. Thus, the entire bandwidth is achieved within 4 milliseconds.

[0051] For example, the number of partial measurement intervals (partial scans) is between 2 and 10. However, more partial measurement intervals can also be provided, which can result in the measurement pauses between adjacent partial measurement intervals being shorter. The measurement intervals can have the same length or different lengths. In Figure 1 they are not shown equally long.

[0052] The partial scans can overlap one another in order to, for example, reduce transient effects. The software then needs to know the overlap points and exclude them when combining. Figure 2 and Figure 3 This is shown.

[0053] In these cases, different approaches can be taken: The control-type phase-locked loop (PLL) is either always active or temporarily completely switched off. If overlapping partial scans are implemented, the PLL can also approach the new start frequency in a falling ramp and then continue the scan again. Figure 3 This is shown. This means that the "start-up time" of the PLL, i.e. the start-up phase and the adjustment phase to the start frequency, can be omitted or shortened. In addition, the subsequent VCO does not remain at one frequency, which can lead to disturbances within the device.

[0054] In general, the VCO is always connected downstream of the PLL. During the measurement scan pauses, the VCO can also be switched off or remain active. Here, too, various implementations are possible.

[0055] Thus, there are many possible and desirable implementation forms. It is important that during the "non-working phase" (measurement pause) no radio frequency transmission signal reaches the antenna and thus no radar measurement signal is transmitted.

[0056] If multiple different frequency scans / bandwidths are implemented in the radar measurement device, it is also possible to divide them variably into multiple partial scans. This means that the software can be configured according to the set frequency deviation to decide how many partial scans are implemented.

[0057] This automation process can also be applied according to the applicable radio license (country dependency). If the limit value is high enough, it can be possible to measure in one scan; otherwise it has to be divided. Here, too, the actual transmission power can be monitored, for example by a power detector. This measured value can be used as an input parameter for the automation process.

[0058] During the pause time, the frequency can be minimized (= starting frequency of the first partial scan or frequency of the VCO with 0V tuning voltage for the following). In general, the frequency during the transmission pause can be fixed or variable (fixed or free). A mix of scan division and transmission power reduction can also be implemented. In particular, a combination can be made depending on the application, the radio certification and the maximum radio frequency transmission power available. A scan interruption before the maximum possible average transmission power is reached can be targeted as a given goal. At this point, a "safety margin" can also be provided.

[0059] In other words, the control unit can be particularly configured to continuously calculate the average transmission power that has been transmitted and to timely interrupt the frequency traversal by inserting a measurement pause before the maximum permissible average transmission power is reached.

[0060] Scan division can also be provided for energy reasons, for example when the energy of the sensor is scarce or becomes scarce. In this consideration, it should be taken into account that a smaller energy storage can be selected for short scans (or partial scans) required by the radar measurement device.

[0061] If the PLL and / or the downstream VCO cannot generate the ramp as quickly as required, it can also be necessary to make a scan division. If the system speed has to be "slowed down" for these reasons, a large frequency ramp (large radar bandwidth) can only be achieved by a longer scan time, which can not be compatible with energy or radio license requirements.

[0062] In this context, it should be noted that in the present disclosure the terms "partial scan" and "partial measurement interval" correspond to each other.

[0063] The sampling frequency can also be taken into account in the automated measuring method. Thus, if necessary, the frequency ramp can be realized faster or shorter; and, if necessary, the sampling rate can also be increased and thus the same number of sampling points can be obtained. This variant is particularly possible if the analog-digital converter is able to convert fast enough.

[0064] Figure 4 A radar measuring device 100 according to an embodiment of the present disclosure is shown. The radar measuring device 100 is designed as an FMCW level radar measuring device and, in addition to a control unit 101 and a radar module 102, also has an antenna 103 for transmitting radar measuring signals and receiving reflected radar measuring signals again.

[0065] In addition, the radar measuring device 100 also has a power detector 104 and a data memory 105. A phase-locked loop (PLL) is part of the control unit 101 or the radar module 102.

[0066] Figure 5 A flowchart of a method according to an embodiment of the present disclosure is shown. In step 501, the average transmission power of the radar measuring signals to be transmitted during a measurement interval is calculated. In step 502, the calculated average transmission power is compared with a predetermined threshold power, and in step 503, the measurement interval is divided into a plurality of consecutive partial measurement intervals as a result of the calculated average transmission power being greater than the predetermined threshold power. In step 504, the consecutive partial measurement intervals are separated from one another by measurement pauses in order to reduce the average transmission power of the radar measuring signals to be transmitted so that it falls below the predetermined threshold. In step 505, the radar measuring signals are transmitted during the consecutive partial measurement intervals. The transmitted radar signals are reflected, for example, on the surface of the filling material and are received again by the antenna of the radar measuring device in step 506 and are "combined" by the control unit in order to calculate the level.

[0067] In addition to dividing the measurement interval into partial measurement intervals and inserting measurement pauses between them, it is also possible to reduce the scan time as a whole. This leads to a reduction in the number of sampling points at the same sampling rate. The frequency deviation or the bandwidth can also be reduced. In addition, the overall transmission power can also be reduced. In addition, as described above, the slope of the frequency ramp can be increased in order to reduce the measurement time and at the same time increase the measurement pauses between the partial measurement intervals.

[0068] Reference of Related Applications

[0069] This application claims priority to German patent application 102024109825.2, filed April 9, 2024, the contents of which are incorporated herein in their entirety by reference.

Claims

1. A radar measuring device (100) configured for process automation in an industrial or private environment, comprising: a control unit (101) configured to calculate an average transmission power of a radar measurement signal to be transmitted during a measurement interval, The control unit (101) is configured to compare the calculated average transmission power with a predetermined threshold power, and to divide the measurement interval into a plurality of consecutive partial measurement intervals when the calculated average transmission power is greater than the predetermined threshold power. Therein, the consecutive partial measurement intervals are separated from one another by measurement pauses in order to reduce the average transmission power of the radar measurement signal to be transmitted so that it falls below the predetermined threshold value.

2. The radar measuring device (100) according to claim 1, further comprising: A radar module (102) is configured to generate and transmit the radar measurement signal during the consecutive partial measurement intervals.

3. The radar measuring device (100) according to any one of the preceding claims, in, The radar measuring device (100) is an FMCW radar measuring device.

4. The radar measuring device (100) according to claim 3, in, The control unit (101) is configured to determine the number of the partial measurement intervals according to the size of the frequency deviation of the entire frequency traversal of the measurement interval and / or according to the maximum transmission power of the radar measurement signal to be transmitted when the measurement interval is divided into the plurality of consecutive partial measurement intervals.

5. The radar measuring device (100) according to claim 3 or 4, in, The control unit (101) is configured to determine the length of the measurement pause between two consecutive partial measurement intervals based on the size of the frequency deviation of the entire frequency traversal of the measurement interval and / or based on the maximum transmission power of the radar measurement signal to be transmitted when the measurement interval is divided into the plurality of consecutive partial measurement intervals.

6. The radar measuring device (100) according to any one of claims 3 to 5, in, The control unit (101) is configured to reduce the slope of the frequency ramp of the frequency traversal when the measurement interval is divided into the plurality of consecutive partial measurement intervals.

7. The radar measuring device (100) according to any one of the preceding claims, During the measurement pauses between the consecutive partial measurement intervals, the radar measurement signal is not emitted.

8. The radar measuring device (100) according to any one of claims 3 to 7, in, The control unit (101) is configured to, when the calculated average transmission power is greater than the predetermined threshold power, perform the frequency traversal faster and simultaneously increase the sampling frequency of the radar measurement signal.

9. The radar measuring device (100) according to any one of the preceding claims, in, Even if the measurement interval is divided into the plurality of consecutive partial measurement intervals, the maximum transmission power of the radar measurement signal to be transmitted does not vary.

10. Use of the radar measuring device (100) according to any one of the preceding claims for fill level measurement.

11. Use of the radar measuring device (100) according to any of the preceding claims for object detection or room monitoring.

12. A method for measuring using a radar measuring device (100) for process automation in an industrial or private environment, the method comprising the following steps: Calculate the average transmit power of the radar measurement signal to be transmitted during the measurement interval; comparing the calculated average transmit power with a predetermined threshold power; When the calculated average transmit power is greater than the predetermined threshold power, dividing the measurement interval into a plurality of consecutive partial measurement intervals; Therein, the consecutive partial measurement intervals are separated from one another by measurement pauses in order to reduce the average transmission power of the radar measurement signal to be transmitted so that it falls below the predetermined threshold value.

13. A program product which, when executed on a control unit (101) of a radar measuring device (100), instructs the radar measuring device (100) to execute the steps according to claim 12.

14. A computer-readable medium storing the program product according to claim 13.

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