Field device for wireless data transfer

Abstract

The invention relates to a field device (100) for wireless data transfer, comprising: an antenna system (300) which is signal-coupled to a transceiver module (400) of the field device (100), wherein the antenna system (300) is designed: to emit and / or receive electromagnetic signals for wireless data transfer; and to selectively modify, in relation to the field device (100), an antenna radiation pattern (120, 140) for transmitting and / or receiving the electromagnetic signals.

Description

[0001] Description

[0002] title

[0003] Field device for wireless data transmission

[0004] Reference to related applications

[0005] This application claims priority from German patent application No. 102023 133 983.4, filed on December 5, 2023, which is incorporated in its entirety by reference into this document.

[0006] background

[0007] Field devices such as level, pressure, or point level sensors or actuators can transmit data wirelessly. This data transmission can be performed in addition to wired communication (4...20 mA, HART, Profibus, Foundation Fieldbus, APL, IO-Link, etc.) or exclusively wirelessly.

[0008] Disclosure of the invention

[0009] In wireless data transmission from a field device to a transmitting / receiving point, sufficient signal strength or a sufficient signal-to-noise ratio (SNR) can be crucial for reliable communication and / or energy-efficient communication. However, field devices are deployed in different environments and with different spatial orientations or different installation positions.

[0010] According to aspects of the invention, a field device for wireless data transmission and a use of the field device according to the features of the independent claims are proposed. Advantageous embodiments are the subject of the dependent claims and the following description.

[0011] According to one aspect, a field device for wireless data transmission is proposed, comprising an antenna system and a transmit / receive module. The antenna system is signal-coupled to the transmit / receive module of the field device. The antenna system is configured to emit and / or receive electromagnetic signals for wireless data transmission. Furthermore, the antenna system is configured to selectively change a directional characteristic for transmitting and / or receiving the electromagnetic signals with respect to the field device.

[0012] The optional change of the directional characteristic is to be interpreted broadly and can mean that the antenna system is designed to optionally change the directional characteristic based on a control signal and / or by selecting a signal-wise coupling.

[0013] By selectively changing the directional characteristic, the antenna system can transmit wireless data from a field device to a transmitting / receiving point with sufficient signal strength and / or with sufficient signal-to-noise ratio (SNR) to ensure reliable communication and / or energy-efficient communication and / or low-power communication.

[0014] A field device (FD), abbreviated to FG, is an electronic device or technical facility that can be used in factory and process automation or in the field of automation technology and is thus designed to be used close to the process. In other words, field devices can be designed to be directly related to a production process and to provide and / or process-relevant information. They can thus be used to record and / or influence process variables. In automation technology, "field" refers to the area outside of control cabinets or control rooms.

[0015] Field devices can be configured as both actuators (control elements, valves, etc.) and sensors (measurement transducers) in factory and process automation. The field device can be configured to collect measurement data at specified intervals and transmit it to the process control system, and can be designed to offer a very high level of reliability.

[0016] Such field devices can be configured to connect to higher-level units via communication networks such as fieldbuses (Profibus®, Foundation® Fieldbus, HART®, etc.) and, in particular, real-time Ethernet. The field device can be configured to connect to a higher-level unit either wirelessly (Wireless Field Device) or via a wired connection. The higher-level unit can be a control unit, such as a PLC (Programmable Logic Controller).

[0017] The higher-level units can be used, among other things, for process control and for commissioning the field devices. The measured values ​​recorded by the field devices, particularly by sensors, can be transmitted via the respective bus system to one or more higher-level units, which may further process the measured values ​​and forward them to a control center of the plant. The control center can be used for process visualization, process monitoring, and process control via the higher-level units. In addition, the field device can be configured to receive data from the higher-level unit to the field devices via the bus system, in particular for configuring and parameterizing the field devices and for controlling actuators.

[0018] The field devices can have sensor systems or be coupled with sensor systems to record process variables. The sensors can be configured, for example, for pressure and temperature measurement, conductivity measurement, flow measurement, pH measurement, pH-redox potential measurement, level measurement, etc., and can determine the corresponding process variables: pressure, temperature, conductivity, pH value, level, flow, dielectric value, and / or pH-redox potential, etc.

[0019] In particular, the respective components of the field device can be arranged in a housing body forming a cavity, which can be closed by means of a housing cover. To ensure sufficient mechanical stability in the event of an explosion, such housings can be designed with comparatively thick walls.

[0020] According to one aspect, it is proposed that the field device with wireless data transmission be used for process control.

[0021] According to one aspect, it is proposed that the field device be configured to selectively change the directional characteristic in order to select a directional characteristic for wireless data transmission. The antenna system can be configured to have at least two different directional characteristics, wherein, in particular, the antenna system can be configured such that at least one of the at least two different directional characteristics can be selected, in particular for data transmission.

[0022] Different criteria may be relevant for selecting the directional characteristics of the antenna system for wireless data transmission.

[0023] These criteria include a received signal strength and / or a signal strength detected by a corresponding transceiver station and provided to the field device or transceiver module. A further criterion may relate to a transmission quality for data transmission detected by the field device and / or a data transmission quality provided to the field device or transceiver unit by a corresponding transceiver station, in particular via wireless transmission. A further criterion may relate to the highest possible signal-to-noise ratio of the electromagnetic signals; and / or include the highest possible and / or the most secure possible data transmission rate.Another criterion may concern the highest possible data rate for wireless transmission, especially if a transmission protocol reduces the data rate for longer distances and poorer signal-to-noise ratios to ensure a stable connection. Another criterion may concern the most efficient and / or energy-saving wireless data transmission possible.

[0024] A field device can include a level, pressure or point level sensor or an actuator.

[0025] The directional characteristic of an antenna system can describe a spatial characteristic of the antenna system's gain. This means that the directional characteristic of an antenna system can describe the spatial direction in which the antenna system detects electromagnetic signals more sensitively or transmits them more effectively.

[0026] Advantageously, the field device can select the directional characteristic in the corresponding installation situation that is relevant for a specific criterion with regard to wireless data transmission and / or is optimized with regard to the directional characteristic of a corresponding transmit / receive point according to the criteria for wireless data transmission described above. This is because the installation situation for the field device can be spatially oriented in different ways and / or placed at different locations in process vessels. By adjusting the directional characteristic after installation of the field device, the wireless transmission of signals can be improved and / or the range of the wireless transmission can be increased. By selecting the directional characteristic accordingly, energy for transmission can be saved, as less transmission energy is required to achieve a sufficiently good signal-to-noise ratio.For this purpose, the directional characteristics of the antenna system of the field device and the directional characteristics of a corresponding transceiver station can be coordinated to increase the quality and range of the wireless data transmission.

[0027] The data transmission can concern different tasks related to an Internet of Things (loT) and / or in particular monitoring and / or predictive maintenance.

[0028] Based on a suitably selected directional characteristic of the field device's antenna system, the range of wireless data transmission can be increased to require a smaller number of transmit / receive points or gateways to cover a larger area. The selected directional characteristic of the antenna system can be particularly suitable for wireless

[0029] be suitable for data transmission if it corresponds to a directional characteristic of a receiving point.

[0030] According to one aspect, it is proposed that the transmitting / receiving module is configured to control the directional characteristic of the antenna system; and, depending on the selected directional characteristic, alternatively or additionally, to determine a received signal strength and / or receive a signal strength from a corresponding transmitting / receiving station; and / or to determine a transmission quality for the data transmission; and / or receive a transmission quality for the data transmission from the corresponding transmitting / receiving station; in particular to select the directional characteristic for the wireless data transmission.

[0031] This ensures that electromagnetic signals are transmitted with as little energy as possible and with as high quality as possible.

[0032] The directional characteristic of the antenna system can be selected according to signal strength and / or communication direction. Depending on the reception, the field device can be configured to communicate with the antenna system using a preferred directional characteristic, for example, one that requires the lowest power and / or enables the most stable connection.

[0033] According to one aspect, it is proposed that the transmitting / receiving module is configured to select the directional characteristic of the antenna system for data transmission when communication between the field device and the transmitting / receiving station is started and / or periodically and / or depending on the detected and / or received transmission quality with the corresponding transmitting / receiving station and / or the detected or received signal strength.

[0034] According to one aspect, the choice of the directional characteristic of the antenna system can be determined by a transmission protocol used.

[0035] According to one aspect, it is proposed that the antenna system has at least a first antenna with a first directional characteristic; and the antenna system has at least a second antenna with a second directional characteristic, which is in particular different from the first directional characteristic, in order to change the directional characteristic of the antenna system by selectively coupling the respective antenna to the transmit / receive module.

[0036] In other words, an actively used first antenna of the antenna system can have a spatially anisotropic directional characteristic. Alternatively or additionally, the second antenna can have a spatially anisotropic directional characteristic, with the two anisotropic directions being perpendicular to each other.

[0037] According to one aspect, it is proposed that the antenna system is mechanically coupled to the field device.

[0038] Alternatively or additionally, the field device has multiple directional antennas, i.e., antennas with spatially anisotropic directional characteristics, with the respective directional antennas being differently aligned. The field device can, in particular by means of the transmit / receive module, select one of the directional antennas, depending, for example, on the one that enables the lowest energy consumption for wireless data transmission and / or the most stable connection for wireless data transmission.

[0039] According to one aspect, it is proposed that at least one antenna of the antenna system has an anisotropic directional characteristic.

[0040] An anisotropic directional characteristic can describe an antenna gain of the antenna system that depends on a spatial direction.

[0041] According to one aspect, it is proposed that the different directional characteristic of at least one of the at least two antennas is caused by an environment of the field device in an installation position and / or mounting position of the field device.

[0042] According to one aspect, it is proposed that the antenna system has the at least one antenna in a first sub-region of the field device and the at least second antenna in a second sub-region of the field device, wherein the respective sub-regions have a different directional characteristic due to the environment of the field device according to the installation position and / or the mounting position of the field device, based on an interaction between the respective antenna and the environment of the field device. A field device with at least two antennas placed at different locations on the field device can have their respective directional characteristics influenced differently by the installation position and / or mounting position of the field device, in particular with respect to large metal-containing objects.Advantageously, the antenna system of the field device can be selected according to a favorable directional characteristic in this installation position and / or mounting position of the field device. According to one aspect, it is proposed that the different antenna characteristic of at least one of the at least two antennas be created by means of a metallic device corresponding to an antenna reflector and / or antenna director for electromagnetic radiation.

[0043] Such an antenna reflector can, in particular, be a parabolic reflector and / or an antenna reflector corresponding to a Yagi antenna. The antenna director can be designed corresponding to an antenna director of a Yagi antenna.

[0044] According to one aspect, it is proposed that the antenna system is configured to interact with at least one of the at least two antennas based on the at least one antenna director and / or the at least one antenna reflector in order to emit and / or receive electromagnetic radiation in a spatially directed manner according to the directional characteristic.

[0045] According to one aspect, it is proposed that the metallic device is arranged within a housing of the field device.

[0046] According to one aspect, it is proposed that the metallic device is arranged in a wall of the housing of the field device.

[0047] According to one aspect, it is proposed that one of the field devices described above has a position sensor configured to detect a spatial orientation and / or mounting position of the field device. The transmit / receive module can, in particular, be coupled to the position sensor and configured to select the directional characteristic of the antenna system or to propose one of the at least two directional characteristics of the antenna system to the transmit / receive module depending on the detected spatial orientation and / or the mounting position of the housing of the field device.

[0048] The position sensor can be configured to determine an installation position and / or an inclination of the field device and / or an inclination of the antenna system with respect to gravity.

[0049] According to one aspect, it is proposed that the antenna system comprise a rotatable antenna in order to selectively change the directional characteristic for transmitting and / or receiving the electromagnetic signals relative to the field device by means of an orientation of the rotatable antenna. In other words, the antenna system can be configured to rotate the directional characteristic of the antenna system in a direction of the transmitting / receiving point and / or to pivot it three-dimensionally. The transmitting / receiving module can be configured to control this rotation and / or pivoting. The spatial orientation of the directional characteristic of the rotatable antenna can be based on a rotation of the rotatable antenna.

[0050] According to one aspect, it is proposed that one of the field devices described above comprises a data module, wherein the data module is signal-coupled to the transmitting / receiving module in order to receive data from the transmitting / receiving point and / or to provide data of the field device to the transmitting / receiving point.

[0051] The data module can be electrically coupled to an actuator module and / or a sensor module of the field device in order to provide data from the actuator module and / or the sensor module to the data module.

[0052] A use of the field device according to one of the preceding claims for process control is proposed.

[0053] Advantageously, the field device can improve process control, since in particular a greater range of wireless data transmission and / or more secure data transmission can be achieved.

[0054] It is proposed to use one of the antenna systems described above in one of the field devices described above.

[0055] It should also be noted that the various embodiments described above and / or below can be combined with each other.

[0056] Embodiments of the invention are illustrated with reference to Figures 1 to 3 and explained in more detail below. They show:

[0057] Figure 1 shows a field device in a first installation position;

[0058] Figure 2 shows a field device in a second installation position; and

[0059] Figure 3 shows a block diagram of the field device.

[0060] Figure 1a outlines a field device 100 for wireless data transmission, comprising an antenna system that is signal-coupled to a transmit / receive module of the field device 100, wherein the antenna system is configured to emit and / or receive electromagnetic signals for wireless data transmission. Figure 1a outlines a selected first directional characteristic 120 of the antenna system for transmitting and / or receiving electromagnetic signals, relative to the field device 100 in a first installation position in which an axis of symmetry s of the field device 100 is perpendicular to a direction x, wherein the direction x indicates a direction of the first anisotropic directional characteristic 120 of the antenna system in which the antenna gain is maximum. The outlined directional characteristic 120 can be rotationally symmetrical about the axis of symmetry es of the field device, corresponding to a dipole antenna.The direction x can specify a horizontal to which the installation position of the field device 100 is perpendicular.

[0061] Figure 2 outlines the field device 100 in a second installation position in which the axis of symmetry s of the field device 100 is arranged parallel to the direction x of the second directional characteristic 140 of the antenna system, and in which the antenna gain of the antenna system is maximum. Relative to the field device 100, the second directional characteristic 140 is oriented differently, namely perpendicular to the first directional characteristic 120. Here, too, the direction x can indicate a horizontal line with which the installation position of the field device 100, characterized by the axis of symmetry s of the field device, is aligned parallel. The field device 100 is configured to selectively change the directional characteristic 120, 140 for transmitting and / or receiving electromagnetic signals relative to the field device.

[0062] Figure 3 outlines a field device 100 with an antenna system 300, in which two differently aligned antennas are outlined with rectangles, wherein the antenna system 300 is signal-coupled to a transmit / receive module 400. Furthermore, the field device 101 has a data module 500, which is signal-coupled to the transmit / receive module 400 in order to provide the transmit / receive module 400 with data for transmission or to receive and / or store data.

Claims

Claims 1 . Field device (100) for wireless data transmission, comprising: an antenna system (300) which is signal-coupled to a transmit / receive module (400) of the field device (100), wherein the antenna system (300) is configured: - to emit and / or receive electromagnetic signals for wireless data transmission; and - to selectively change a directional characteristic (120, 140) for transmitting and / or receiving the electromagnetic signals with respect to the field device (100).

2. Field device (100) according to claim 1, wherein the transmit / receive module (300) is configured - to control the directional characteristic (120, 140) of the antenna system (300); and depending on the selected directional characteristic (120, 140): - to determine a received signal strength and / or to receive a signal strength from a corresponding transmitting / receiving station; and / or - to determine a transmission quality for the data transmission; and / or to receive a transmission quality for the data transmission from the corresponding transceiver station; in order to select the directional characteristic (120, 140) for the wireless data transmission.

3. Field device (100) according to claim 2, wherein the transmitting / receiving module (300) is configured to start a communication between the field device (100) and the transmitting / receiving station and / or periodically and / or depending on the detected and / or received transmission quality with the corresponding transmitting / receiving station and / or the detected or received signal strength, to select the directional characteristic (120, 140) of the antenna system (300) for data transmission.

4. The field device (100) according to one of the preceding claims, wherein the antenna system (300) comprises at least a first antenna with a first directional characteristic (120, 140); and the antenna system (300) comprises at least a second antenna with a second directional characteristic (120, 140) that is different from the first directional characteristic (120, 140) in order to change the directional characteristic (120, 140) of the antenna system (300) by selectively coupling the respective antenna to the transmit / receive module (300).

5. The field device (100) according to claim 4, wherein at least one antenna of the antenna system (300) has an anisotropic directional characteristic (120, 140).

6. The field device (100) according to claim 4 or 5, wherein the different directional characteristic (120, 140) of at least one of the at least two antennas is caused by an environment of the field device in an installation position and / or mounting position of the field device (100).

7. The field device (100) according to one of claims 4 to 6, wherein the antenna system (300) has the at least one antenna in a first partial region of the field device (100), and the at least second antenna in a second partial region of the field device (100), wherein the respective partial regions, based on the environment of the field device (100), produce a different directional characteristic (120, 140) of the respective antenna according to the installation position and / or the mounting position of the field device (100).

8. The field device (100) according to one of claims 4 to 7, wherein the different antenna characteristics (120, 140) of at least one of the at least two antennas are provided by means of a metallic device corresponding to an antenna reflector and / or antenna director for electromagnetic radiation.

9. The field device (100) according to claim 8, wherein the antenna system (300) is configured to interact with at least one of the at least two antennas based on the at least one antenna director and / or the at least one antenna reflector in order to radiate and / or receive electromagnetic radiation in a spatially directed manner according to the directional characteristic (120, 140).

10. The field device (100) according to claim 8 or 9, wherein the metallic device is arranged within a housing of the field device (100).

11. The field device (100) according to one of claims 8 to 10, wherein the metallic device is arranged in a wall of the housing of the field device (100).

12. The field device (100) according to one of the preceding claims, comprising: a position sensor configured to detect a spatial orientation and / or mounting position of the field device (100); and wherein the transmit / receive module (400) is configured to select the directional characteristic (120, 140) of the antenna system (300) depending on the detected spatial orientation and / or the mounting position of the housing of the field device (100).

13. The field device (100) according to one of the preceding claims, wherein the antenna system (300) has a rotatable antenna in order to selectively change the directional characteristic (120, 140) for transmitting and / or receiving the electromagnetic signals relative to the field device (100) by means of an orientation of the rotatable antenna.

14. The field device (100) according to one of the preceding claims, comprising: a data module (500) signal-coupled to the transmitting / receiving module (400) to receive data from the transmitting / receiving point and / or to provide data of the field device (100) to the transmitting / receiving point.

15. Use of an antenna system (300) in a field device (100) according to one of the preceding claims.

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