Radar module with dual fins

Abstract

The present invention relates to a radar module configured for factory monitoring and comprising a microwave chip including a radar signal source and a coupler connected to the radar signal source and coupling the radar signal generated by the radar signal source into a waveguide or an antenna.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of German patent application 10 2019 204 671.1, filed on April 2, 2019, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present invention relates to radar measurement technology for plant monitoring and process automation. In particular, the present invention relates to a radar module for plant monitoring, a radar measuring device having such a radar module, and the use of the radar module for fill level measurement, limit level measurement, logistics automation, or manufacturing automation. Background Art

[0004] Radar measuring devices are used, for example, in the area of ​​fill level measurement, point level measurement or object detection for process automation, in particular for monitoring plants.

[0005] The radar signal to be transmitted is generated by a radar module having a radar signal source and coupled into a waveguide or an antenna, from which the radar signal is then transmitted in the direction of an object or product to be monitored.

[0006] To this end, common designs of waveguide coupling structures include metal pins, fins, patch antennas or similar structures. Microwave signals are typically connected to circuit components (eg, microstrip structures) on a carrier board via bonding connections.

[0007] Such radar measuring devices can be designed in particular for W-band or K-band frequencies. Summary of the Invention

[0008] It is an object of the present invention to provide an alternative radar module suitable for factory monitoring.

[0009] This object is achieved by the subject matter of the independent claims. Further developments of the invention are given in the dependent claims and in the following description of exemplary embodiments.

[0010] A first aspect of the present invention relates to a radar module configured for factory monitoring, comprising a microwave chip. The microwave chip includes a radar signal source configured to generate a radar signal having a frequency exceeding 75 GHz. The module also includes a coupler (hereinafter also referred to as a coupling element) connected to the radar signal source.

[0011] For example, plant monitoring can involve fill level or limit level measurement. Radar modules can also be configured to monitor hazardous areas of machines, for example in the context of hazardous area monitoring, detect and even identify objects, or detect and count objects on conveyor belts or determine the mass flow of bulk material on conveyor belts.

[0012] The term "process automation" can be understood as a subfield of technology encompassing all measures for operating machines and plants without human intervention. One goal of plant monitoring and process automation is to automate the interaction of individual plant components in the chemical, food, pharmaceutical, oil, paper, cement, shipping, or mining industries. For this purpose, a wide range of sensors can be used, which are particularly well-suited to the specific requirements of the process industry, such as mechanical stability, insensitivity to contaminants, and extreme temperatures and pressures. The measured values ​​of these sensors are typically transmitted to a control room, where process parameters such as fill level, limit level, flow, pressure, or density can be monitored, and overall plant settings can be modified manually or automatically.

[0013] A subfield of process automation is logistics automation. In the field of logistics automation, processes within buildings or individual logistics equipment are automated with the help of distance sensors and angle sensors. Typical applications are logistics automation systems for the following areas: baggage handling and cargo handling at airports, traffic monitoring (toll collection systems), trade, parcel delivery, or building security (access control). The common point of the examples listed above is that each application requires the combination of presence detection with the precise measurement of the size and position of objects. For this purpose, sensors based on optical measurement methods using lasers, LEDs, 2D cameras, or 3D cameras can be used, which detect distances according to the time of flight principle (ToF).

[0014] Another subfield of process automation involves factory / manufacturing automation. Examples of this application can be found in many industries, such as automotive, food, pharmaceutical, 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 sensors used here, and the specific requirements for measurement accuracy when detecting the position and size of objects, are comparable to those used in the logistics automation example mentioned above.

[0015] The use of high frequencies reduces the overall size of the antenna and coupler, as well as the waveguide or antenna coupling structure of which the coupler is a part. As a result, all components of the radar signal coupling structure can be integrated directly on the microwave chip.

[0016] The radar signal generated by the radar signal source of the microwave chip is coupled directly from the microwave chip into the waveguide or directly into the antenna. In particular, the radar signal source is configured to generate a radar signal with a frequency greater than 75 GHz or greater than 150 GHz, or alternatively, a radar signal with a frequency greater than 200 GHz, particularly greater than 240 GHz.

[0017] According to one embodiment, the coupler includes two fins arranged opposite each other and, for example, mirror-symmetrically. These two fins convert the transmit signal generated by the radar signal source into electromagnetic waves, which then propagate in a waveguide or horn antenna. The connection between the radar signal source and the fins is also made in the microwave chip, largely avoiding disruptive transitions from the radar signal source (HF generator) to the line and vice versa, thereby reducing interfering reflections.

[0018] According to an embodiment, the two fins are configured to transmit symmetrical radar signals.

[0019] In order to improve the coupling characteristics, one or more steps may be provided in the coupling region.

[0020] According to another embodiment, the radar module includes a frame surrounding the two fins, protecting them from external mechanical influences. This frame is used to connect to the waveguide or directly to the antenna. A dielectric component of the microwave chip can be disposed within and around the frame. In this case, the dielectric is, for example, the top layer of the chip.

[0021] According to another embodiment, the two fins are surrounded by a cavity (which may also be referred to as a resonance cavity), which is at least partially filled with a dielectric.

[0022] According to another embodiment, the chamber is filled with atmospheric gas.

[0023] According to a further embodiment, the coupler is a coupling pin or a patch antenna.

[0024] According to another embodiment, the coupler and the radar signal source are connected to each other via a common substrate. The substrate is a layer of the microwave chip. The signal connection between the radar signal source and the coupler can be configured to have as little attenuation as possible, thereby affecting the sensitivity of the radar module as little as possible. Since no bonding wires are provided for connecting the coupler to the radar signal source, , so variations in the length and position of the bond wires will not negatively impact the performance of the radar module.

[0025] According to another embodiment, a radar module includes a waveguide and / or an antenna. The coupler is configured to couple a radar signal into the waveguide and / or the antenna, wherein the waveguide is configured to transmit the coupled radar signal. The antenna is configured to transmit the coupled radar signal and receive an echo.

[0026] According to another embodiment, the antenna is a horn antenna and optionally has a connection in the form of a waveguide.

[0027] According to a further embodiment, the radar module is designed to generate a radar signal having a transmission frequency exceeding 200 GHz.

[0028] According to another embodiment, the diameter of the resonant cavity is smaller than 1.5 mm.

[0029] Another aspect relates to a radar measuring device having the radar module described above and described below.

[0030] Another aspect relates to the use of the radar modules described above and below for fill level measurement, limit level measurement, logistics automation or production automation.

[0031] The embodiments will be described below with reference to the accompanying drawings. The illustrations in the accompanying drawings are schematic and not drawn to scale. If the same reference numerals are used in the following description of the drawings, they represent the same or similar elements. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 A radar module according to an embodiment is shown.

[0033] Figure 2 Show Figure 1 A top view of the radar module.

[0034] Figure 3 A perspective view of a radar module according to an embodiment is shown.

[0035] Figure 4 A radar measuring device is shown having the radar modules described above and below. DETAILED DESCRIPTION

[0036] Figure 1 A small part of a radar module 100 of a radar measuring device according to an embodiment is shown. Radar modules are used in the field of process automation, in particular for plant monitoring.

[0037] The radar module includes a microwave chip 101 on or in which a radar signal source 102 is formed. A coupler 103 is provided, for example in the form of two fins 105 and 106 arranged opposite each other. The radar signal source is connected to one of the two fins 105 via an electrical connector 116 connected to the radar signal source 102.

[0038] The chip itself forms a resonant cavity, which is formed by the metal frame 107 and in whose chamber the coupler 103 is located. The frame serves to connect the coupling structure to a waveguide or directly to an antenna.

[0039] Frame 107 and couplers 103 / 105 are at least substantially made of metal and are, for example, at least partially embedded in a dielectric layer of microwave chip 101. The dielectric layer may extend approximately to the height of the end face of coupler 103 or beyond, so that coupler 103 is completely embedded in the dielectric layer.

[0040] The cross-section of the resonant cavity may be configured as a rectangle with a width greater than its depth, for example, a width approximately twice the depth.

[0041] The steps 109, 110 may be provided on the two narrower sides of the resonant cavity (see in particular Figure 2 ), through which the coupling characteristics can be improved.

[0042] Figure 2 Show Figure 1 The second fin 106 is located on a ground plane 115 , which is conductively connected to the frame 107 .

[0043] Between the oppositely arranged fins 105 , 106 there is a cavity 108 which may be at least partially filled with a dielectric.

[0044] Figure 3 Another embodiment of radar module 100 is shown, in which the bottom of frame 107 is designed to be narrower than the upper region of frame 107. In the lower region, grooves are provided on the opposite longer sides of the frame. An electrical connector 116 connected to first fin 105 passes through one of the grooves.

[0045] Figure 3 The three layers of the microwave chip 101 are shown. Reference numeral 111 denotes a dielectric layer, above and below which are metal layers 112 and 113, respectively. A further dielectric layer may be provided above the metal layer 113, for example formed to a dotted line 114, so that the frame 107 protrudes therefrom.

[0046] Another waveguide is connected to the frame 107, or an antenna is directly connected to the frame.

[0047] Due to the high frequency of radar signals (greater than 75GHz), the mechanical design of the dual fins is so small that it can be easily integrated into a microwave chip.

[0048] By means of two fins 105, 106 arranged mirror-symmetrically opposite each other, the radar signal is fed into the waveguide or antenna via the resonant cavity 108. As a result, the electromagnetic wave is released symmetrically into the waveguide or horn antenna from the outset and is not absorbed.

[0049] By filling the resonant cavity 108 around the two fins with a microwave-compatible dielectric, the mechanical design of the device is reduced due to the resulting (physical, wave) shortening factor, which can lead to corresponding savings in space on the chip and thus in costs.

[0050] Since the radar module is integrated on the chip, no external connection lines are required between the chip and the dual fins. This avoids reflections, improves the so-called ringing behavior of the radar module, and saves costs.

[0051] The use at high frequencies reduces the size of the mechanical elements of the waveguide coupling structures or antenna coupling structures to the point where they can be directly integrated into microwave chips.

[0052] The dual fins can be constructed like other chip components during chip production, by arranging copper and dielectric accordingly. In this case, the space between the two fins can be left with air or filled with dielectric. Which of the two variations is preferred depends on the type of antenna being fed, for example, a dielectric conductor or an unfilled horn.

[0053] Figure 4 A radar measuring device 400 is shown, which includes the above-described radar module 100 and a horn antenna 401 connected thereto.

[0054] Furthermore, it should be noted that "comprising" and "having" do not exclude other elements or steps, and the indefinite article "a" or "an" does not exclude a plurality. It should also be noted that features or steps described with reference to one of the above exemplary embodiments can also be used in combination with other features or steps of other exemplary embodiments described above. Reference signs in the claims should not be considered as limitations.

Claims

1. A radar module (100) configured for factory monitoring, the radar module comprising a microwave chip (101), the microwave chip having: - a radar signal source (102) configured to generate a radar signal having a frequency exceeding 75 GHz, - a metal frame (107) forming a chamber (108); and - a coupler (103) arranged inside the chamber (108) formed by the metal frame (107), the coupler (103) having two fins (105, 106) formed of metal and arranged opposite each other, wherein One of the two fins (105, 106) is connected to the radar signal source (102), and the other of the two fins (105, 106) is connected to the metal frame (107).

2. The radar module (100) according to claim 1, in, The two fins (105, 106) are configured to transmit symmetrical radar signals.

3. The radar module (100) according to claim 1 or 2, in, The metal frame (107) surrounds the two fins (105, 106) such that the metal frame (107) protects the two fins (105, 106) from external mechanical influences.

4. The radar module (100) according to claim 1 or 2, in, The two fins (105, 106) are surrounded by the chamber (108); Wherein, the cavity is filled with a dielectric.

5. The radar module (100) according to claim 1 or 2, in, The two fins (105, 106) are surrounded by the chamber (108); Wherein, the chamber is filled with atmospheric gas.

6. The radar module (100) according to claim 1 or 2, in, The coupler (103) and the radar signal source (102) are connected to each other via a common substrate (111).

7. The radar module (100) according to claim 1 or 2, in, The radar module includes a waveguide and / or an antenna (401); wherein the coupler (103) is configured to couple the radar signal into the waveguide or the antenna; The waveguide is configured to transmit the coupled radar signal.

8. The radar module (100) according to claim 7, in, The antenna is a horn antenna.

9. A radar measuring device (400) comprising the radar module (100) according to any one of claims 1 to 8.

10. Use of the radar module (100) according to any one of claims 1 to 8 for filling level measurement, limit level measurement, logistics automation or manufacturing automation.

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