Communication system for a communication network of a technical installation

Abstract

The invention proposes a communication system (2) for operating an in particular 5G-based wireless communication network (1) in a technical installation, in particular a manufacturing or process installation, wherein the communication system (2) is designed a) to receive a request directed from a terminal (3a, 3b) to the communication system (2), wherein the request comprises a format of a time division duplex (TDD) method requested by the terminal (3a, 3b) for communication in the 5G-based communication network (1), b) checking the request from the terminal (3a, 3b), and c) in the event that the communication system (2) is able to meet the request from the terminal (3a, 3b), providing communication for the terminal (3a, 3b) based on the time division duplex (TDD) method with the requested format.

Description

[0001] Description

[0002] Communication system for the communication network of a technical plant

[0003] The invention relates to a method for operating a communication network, in particular one based on 5G, in a technical plant, especially a manufacturing or process plant. The invention further relates to a communication system for operating a communication network, in particular one based on 5G, in a technical plant, especially a manufacturing or process plant, and to a communication network. The invention also relates to a communication network comprising a communication system and an end device configured to send a request to the communication system.

[0004] Mobile communication systems such as 5G NR (new radio) specified by the standardization body 3GPP (3rd Generation Partnership Project) operate according to FDD (Frequency Division Duplex) or TDD (Time Division Duplex).

[0005] In FDD, separate frequency ranges are available for the downlink (DL, transmission of data from the network to the end device) and the uplink (UL, transmission of data from the end device to the network).

[0006] In TDD, DL and UL share a frequency range, which is used alternately by DL and UL over time.

[0007] For easier coordination, usage is divided into so-called time slots, which are assigned to the DL (downstream) and UL (upstream) respectively. The allocation of time slots for 5G NR is hierarchically structured and flexible. The basis is a "radio frame" with a length of 10 ms. Each radio frame consists of 10 subframes, each 1 ms long. A subframe consists of at least one and up to 16 slots. A slot consists of 12 or 14 symbols.

[0008] The division into DL and UL is controlled by the symbols used in the slots. 3GPP specifies symbols for DL, for UL, and so-called flexible symbols that can be used for both DL and UL. 3GPP has specified a number of TDD formats with different divisions (TS 38.213), which are explained, for example, at https: / / www.5gfundamental.com / 2020 / 05 / tdd-ul-dl-slot-configuration.html.

[0009] In simplified terms, there are various TDD formats for data transmissions, focusing on a strong DL, a strong UL, or with a near-symmetrical allocation. Depending on the requirements, a TDD format can therefore be used – at least theoretically – that allocates a large portion of the data transmission capacity to either the DL or the UL, or that is flexible.

[0010] In industrial applications, particularly in automation technology, there are diverse requirements for the characteristics of the communication infrastructure. For example, some applications involve a) large amounts of data being transmitted to end devices via downstream (e.g., software download), b) large amounts of data being transmitted from end devices via upstream (e.g., video upload), or c) approximately equal amounts of data being transmitted to and from end devices (e.g., controller-to-controller communication). Furthermore, there are applications with varying transmission intervals and latency and jitter requirements. Often, a single production plant contains examples of all these applications. Therefore, a communication system should ideally meet all these requirements as effectively as possible. However, despite the options and flexibility specified in the 5G standard, this is not always automatically the case in practice.

[0011] Due to typical user behavior (many downloads, few uploads), public mobile network operators (MNOs) use a frame or TDD format with high DL and low UL. This format is not changed during network operation.

[0012] If multiple MNOs use adjacent frequency bands, mutual interference must be avoided. To achieve this, the networks are synchronized, meaning they use a common time base (GPS) and UL and DL transmissions occur simultaneously. This means the MNOs use the same TDD format. Alternatively, a so-called "guard band" can be implemented. The guard band is an unused 20-25 MHz wide frequency band located between the MNOs' frequency bands. With a guard band, it is possible for two MNOs to use different TDD formats and / or operate unsynchronized. In practice, however, a guard band is not used to avoid leaving any spectrum unused.

[0013] In the future, local private 5G mobile networks will be increasingly used in industry. These are small 5G networks, typically limited to the premises of an industrial plant or factory and operating independently of public mobile networks. Local private 5G networks usually use a frequency range reserved for such networks or spectrum provided by a mobile network operator (MNO), for example, through leasing.

[0014] A local private 5G network, like a public 5G network, uses a specific predefined TDD format. Since comparable technology is used, this is usually the same as in public 5G networks (strong DL, weak UL), but other TDD formats, such as one with symmetrical DL and UL, are also possible in principle. The selected TDD format is used throughout the entire 5G network; that is, all Radio Units (RUs) operate with this TDD format.

[0015] In practical operation, the configured TDD format may not meet the requirements of an application, for example, if more data needs to be transmitted than the available DL or UL bandwidth allows, or if shorter transmission intervals are required. This can occur, for instance, when a new application is integrated into the network or if an application's requirements change depending on the time or location. One or more other TDD formats might be suitable to meet the application's requirements.

[0016] The 3GPP standards, however, provide technical options for using a so-called semi-static or dynamic TDD configuration instead of a static TDD format. This would allow a suitable TDD format to be set across the entire SG network or at the cell level – for example, only for a specific RU. These options are not used, however, because interference between neighboring 5G networks in the same or overlapping frequency range, or between cells of a 5G network (inter-cell interference), could lead to transmission problems if they are operated with different TDD formats. German patent DE 10 2020 120 785 A1 discloses a communication device configured to select a bandwidth in an unlicensed spectrum for communication via a fifth-generation (5G) system.

[0017] The invention is therefore based on the objective of providing a method for operating a communication network in a technical plant and an associated communication system that are designed to be more efficient and flexible.

[0018] This problem is solved by a method having the features of claim 1 and by a method having the features of claim 2. Furthermore, the problem is solved by a control system for a technical plant, in particular a process or manufacturing plant, having the features of claim 8. The problem is also solved by a communication system having the features of claim 15, by a communication system having the features of claim 16, and by a communication network having the features of claim 18. Advantageous embodiments are described in the dependent claims.

[0019] A method according to the invention for operating a wireless communication network, in particular a 5G-based wireless communication network, in a technical plant, especially a manufacturing or process plant, wherein the communication network comprises at least one communication system and one terminal device, comprises the following method steps: a) the terminal device sends a request to the communication system, wherein the request includes a format of a Time Division Duplex (TDD) method requested by the terminal device for communication in the communication network, b) the communication system checks the terminal device's request, c) if the communication system can fulfill the terminal device's request, provides communication to the terminal device based on the Time Division Duplex (TDD) method with the requested format.

[0020] The communication system of the communication network organizes communication within the communication network, particularly between the end device and other participants in the communication network. The communication system can, especially in the case of a 5G-based communication network, include a core processing unit, a RAN processing unit, at least one radio unit, and / or at least one small cell. In the context of 5G, the core processing unit is also referred to as the "5G Core." The RAN processing unit, also referred to as the "5G Radio Access Network" in the context of 5G, can comprise a "Central Unit (CU)" and a "Distributed Unit (DU)."

[0021] A "small cell" is a compact communication unit that provides local network coverage within a technical facility. It serves to increase wireless network capacity, particularly in areas with high local demand. Small cells can come in various forms, such as femtocells, picocells, or microcells, depending on the size of the area they are intended to cover.

[0022] A "Radio Unit" (RU) is a component responsible for transmitting and receiving radio signals. It is part of a larger base station or radio access point. The Radio Unit converts electrical signals into radio signals and transmits them wirelessly over the air to end devices. A Radio Unit typically comprises various hardware components such as transmitters, receivers, antennas, and digital signal processors. It operates using various transmission standards such as GSM, CDMA, LTE, or 5G, depending on the specific requirements of the communication network.

[0023] The present invention is based on two equivalent alternative methods: First, the terminal device can request a specific format of a Time Division Duplex (TDD) method from the communication system for communication within the communication network. In other words, the terminal device requests the communication system, as the entity managing the communication network, to provide it with a specific format for the Time Division Duplex method for communication within the communication network. This could mean, for example, that the terminal device requests a format with a high upload component, since it itself receives hardly any data from the communication network, but mainly sends data. Conversely, the terminal device can also request a format with a high download component.In this variant, the terminal device is aware of the formats usable by the communication network for the Time Division Duplex (TDD) protocol. Alternatively, the terminal device can also send a request to the communication system, where the request includes conditions for the terminal device to perform a communication task. The terminal device can specify concrete conditions to the communication system regarding bandwidth, the distribution between download and upload, or latency. For this, the terminal device does not need to have knowledge of the possible formats for the Time Division Duplex (TDD) protocol. The communication system checks the terminal device's request and determines whether a format of a Time Division Duplex (TDD) protocol used for communication with the terminal device in the communication network meets the conditions of the request.

[0024] Such a method for operating a wireless communication network, in particular one based on 5G, in a technical plant, especially a manufacturing or process plant, wherein the communication network comprises at least one communication system and one terminal device, comprises the following steps: a) the terminal device making a request to the communication system, wherein the request includes conditions for the terminal device to perform a communication task; b) the communication system checking the terminal device's request to determine whether a format of a Time Division Duplex (TDD) method used for communication with the terminal device in the communication network meets the conditions of the request; c) if the communication system can fulfill the terminal device's request, providing communication to the terminal device based on the conditions of the request.

[0025] Preferably, if the communication system cannot fulfill the terminal's request using any possible Time Division Duplex (TDDuplex) format, it sends a corresponding message to the terminal. This allows the terminal to react, for example, by modifying its request, if possible, and sending a revised request to the communication system. This can be an iterative process until a consensus is reached between the terminal and the communication system. The terminal can send the request to the communication system in anticipation of a communication task. A communication task is understood as a specific communication with one or more communication partners under certain conditions. The anticipation of such an upcoming communication task can trigger the terminal to send the request to the communication system.

[0026] The end device can also send a request to the communication system in response to the failure to meet certain conditions of an ongoing communication between the end device and the communication system. If the end device detects during the ongoing communication that certain conditions are not being met, this triggers the request to the communication system. These conditions could include data rate, latency, or jitter in the ongoing communication between the end device and the communication system.

[0027] In a preferred embodiment of the invention, the terminal device sends the request to the communication system by specifying one or more 5QI values ​​and transmitting these 5QI values ​​to the communication system. The term 5QI stands for "5G Quality of Service (QoS) Identifier." The 5QI values ​​correspond to a set of QoS (Quality of Service) characteristics intended for use in QoS flow. These characteristics include guaranteed and maximum bit rates, priority levels, and limits for latency, jitter, and error rate. This configuration of the request allows it to be transmitted to the communication system simply and efficiently without the need to define additional transmission parameters.

[0028] Preferably, the communication system provides communication to the terminal device based on the Time Division Duplex (TDD) method with the requested format by specifying the TDD method with the requested format for all connections within the communication network. In this embodiment of the invention, all communication connections are configured based on the TDD format requested by the terminal device. This approach is particularly suitable for relatively small communication networks with few participants.

[0029] The communication system can also provide communication to the end device based on the Time Division Duplex (TDD) method with the requested format by specifying the TDD method with the requested format for communication to a portion of the connections within the communication network, particularly for one or more 5G Radio Units or 5G Small Celis. In other words, the requested TDD format is not specified for the entire communication network, but only for a part of it. This means that not all communication network participants have to change their communication format, but only a specific group.Preferably, the communication system provides communication to the end device using the Time Division Duplex (TDD) method with the requested format by specifying the TDD method with the requested format for communication to the 5G Radio Unit(s) or 5G Small Celis within range of the end device. This allows the end device to communicate using the requested format without requiring all participants in the communication network to do so (which could potentially have disadvantages).

[0030] In a preferred embodiment of the invention, the communication system checks whether specifying the Time Division Duplex (TDD) method with the requested format would cause, or actually causes, transmission interference due to interference between the individual 5G Radio Units or 5G Small Celis. This allows the communication system to effectively prevent transmission interference from occurring in the first place due to the format change. Furthermore, even after switching to the requested format, the communication system can repeatedly check for transmission interference and, if necessary, reverse the change.As part of this test, the communication system can, for example, check the RSSI (Received Signal Strength Indicator) values ​​of neighboring cells in the communication network or the SINR (Signal-to-Noise Ratio) value when communicating using the new format for the Time Division Duplex (TDU) method. Preferably, the 5G Radio Units or 5G Small Celis are operated in a radio frequency range above 24 gigahertz. In this frequency range, the range is short, and therefore the risk of interference with neighboring 5G Radio Units or 5G Small Celis in the same frequency range is low, making the conversion of individual 5G Radio Units or 5G Small Celis less error-prone.

[0031] 5G Radio Units or 5G Small Celis particularly favor establishing a connection to the end device via beamforming, with the beamforming specifically limited to a safety area twice the size of the end device. In 5G, "beamforming" refers to focusing the direction of the radio signal to improve the performance and efficiency of wireless communication. The end device is selected as the target for the radio signal by increasing the transmission power in that direction. This enables direct and focused communication between the 5G Radio Units or 5G Small Celis and the end device, which can lead to better signal quality and higher data rates. Specifically, focusing the beamforming can further reduce the risk of transmission interference caused by the change in the Time Division Duplex (TDDuplex) format.

[0032] The communication system can provide communication to the end device using Time Division Duplex (TDD) with the requested format, utilizing at least a temporary switch to a different radio frequency range. For example, the communication system can operate in both the 3.7–3.8 GHz and 24.25–27.5 GHz frequency ranges, where spectrum is available for campus networks. The communication system can be configured to permanently use different TDD formats in each frequency range, each optimized for different application scenarios. For instance, a symmetrical download / upload ratio can be specified in the 3.7–3.8 GHz range, while a high download speed can be specified in the 24.25–27.5 GHz range.

[0033] The previously formulated task is also solved by a communication system for operating a wireless communication network, in particular based on 5G, in a technical plant, especially a manufacturing or process plant, wherein the communication system is configured to: a) receive a request directed from an end device to the communication system, wherein the request includes a format of a Time Division Duplex (TDD) method requested by the end device for communication in the 5G-based communication network; b) check the request of the end device; and c) if the communication system can fulfill the request of the end device, provide communication for the end device based on the Time Division Duplex (TDD) method with the requested format.

[0034] The previously formulated task is also solved by a communication system for operating a communication network, in particular one based on 5G, in a technical plant, especially a manufacturing or process plant, wherein the communication system is configured to: a) receive a request directed from an end device to the communication system, wherein the request includes conditions for the execution of a communication task by the end device; b) check the end device's request by the communication system to determine whether a format of a Time Division Duplex (TDD) procedure used for communication with the end device in the communication network meets the conditions of the request; c) if the communication system can fulfill the end device's request, provide communication for the end device based on the conditions of the request.

[0035] The communication systems described above can each include a core computing unit, a RAN computing unit, at least one radio unit and / or at least one small cell.

[0036] The previously formulated task is also solved by a communication network, comprising a communication system as previously explained and an end device, which end device is trained to direct a request to the communication system as previously explained.

[0037] The properties, features, and advantages of this invention described above, as well as the manner in which they are achieved, will become clearer and more readily understandable in connection with the following description of exemplary embodiments, which are set forth in the

[0038] The connection to the drawings will be explained in more detail. They show:

[0039] FIG 1 shows a schematic representation of a communication network;

[0040] FIG 2 shows a scheme of a first format for a time division duplex method; and

[0041] FIG 3 shows a scheme of a second format for a Time Division Duplex method.

[0042] Figure 1 shows a communication network 1 for a technical plant, in particular a manufacturing or process plant, which comprises a communication system 2, a first terminal 3a, and a second terminal 3b. Figure 1 also shows an automation device 5, which can communicate with the first terminal 3a and the second terminal 3b via the communication system 2. The automation device 5 is connected to the communication system 2 by means of a wired connection.

[0043] The first terminal device 3a and the second terminal device 3b are designed as autonomous vehicles. They each have a 5G-enabled network component 4a, 4b, by means of which they can communicate with the communication system 2 and the automation device 5, respectively.

[0044] The communication system 2 comprises a core processing unit 6, a RAN processing unit 7, a central unit (CU) 8, a distribution unit 9 (DU), and a radio unit 10. The radio unit 10 operates in a radio frequency range exceeding 24 gigahertz and uses beamforming to communicate with the end devices 3a and 3b in a targeted and focused manner. The beamforming is limited to a safety area twice the size of the end device 3a or 3b. For example, if the end device 3a or 3b has a maximum size of 2 meters, the radiation pattern of the radio waves from the radio unit 10 is essentially concentrated within a 4-meter radius of the end device 3a or 3b. In the course of a method according to the invention, the first terminal device 3a or the second terminal device 3b sends a request to the communication system 2, wherein the request is transmitted wirelessly by means of the network components 4a, 4b.The requirement includes a format of a Time Division Duplex (TDD) method requested by the terminal device 3a, 3b for communication in the communication network 1.

[0045] It is assumed that, prior to the request, at least the communication between the requesting terminal device 3a, 3b and the communication system 2 takes place using a Time Division Duplex (TDD) method, which, in simplified terms, uses a format as shown in FIG. 2. FIG. 2 illustrates that of the ten timeslots of the communication between terminal device 3a, 3b and the communication system 2, six timeslots are used for download (symbolized by a "D") from the communication system 2 to terminal device 3a, 3b, and two timeslots are used for upload (symbolized by a "U") from terminal device 3a, 3b to the communication system 2. Two timeslots are variable and can be used for either download or upload (symbolized by an "S"). The variable timeslots are also referred to as "semi-static TDD configuration" and "dynamic TDD configuration," respectively. The emphasis in the format shown in FIG. 2 is on downloading.

[0046] Communication system 2 checks the request from terminal devices 3a and 3b. If communication system 2 can fulfill the request, it establishes communication for terminal devices 3a and 3b using the Time Division Duplex (TDD) method in the requested format. The new format is shown in Figure 3. It can be seen that of the ten time slots used in the communication between terminal devices 3a and 3b and communication system 2, two time slots are used for download (symbolized by a "D") from communication system 2 to terminal devices 3a and 3b, six time slots are used for upload (symbolized by a "U") from terminal devices 3a and 3b to communication system 2, and two time slots are variable for either download or upload (symbolized by an "S"). The emphasis is therefore now on uploading.

[0047] However, communication system 2 would not necessarily have to change the download time slots into upload time slots (or vice versa). Rather, communication system 2 can also use the variable time slots (marked by "S") as either upload or download time slots.

[0048] Communication system 2 provides communication for terminal devices 3a and 3b based on the Time Division Duplex (TDD) method with the requested format by making the Time Division Duplex (TDD) method with the requested format available to radio unit 10. Communication with other terminal devices not shown in FIG. 1 continues to use the existing Time Division Duplex (TDD) format shown in FIG. 2.

[0049] Although the invention has been illustrated and described in detail by the preferred embodiment, the invention is not limited by the disclosed examples and other variations can be derived by the person skilled in the art without leaving the scope of protection of the invention.

Claims

Patent claims 1. Method for operating a wireless communication network (1), in particular based on 5G, in a technical plant, in particular a manufacturing or process plant, wherein the communication network (1) comprises at least one communication system (2) and an end device (3a, 3b), the method comprising: a) directing a request to the communication system (2) by the end device (3a, 3b), wherein the request includes a format of a Time Division Duplex (TDD) method requested by the end device (3a, 3b) for communication in the communication network (1), b) checking the request of the end device (3a, 3b) by the communication system (2), c) in the event that the communication system (2) can fulfill the request of the end device (3a, 3b), providing communication to the end device (3a, 3b) based on the Time Division Duplex (TDD) method with the requested format.

2. Method for operating a wireless communication network (1), in particular based on 5G, in a technical plant, in particular a manufacturing or process plant, wherein the communication network (1) comprises at least one communication system (2) and an end device (3a, 3b), the method comprising: a) directing a request to the communication system (2) from the end device (3a, 3b), wherein the request includes conditions for the execution of a communication task by the end device (3a, 3b), b) checking the request of the end device (3a, 3b) by the communication system (2) to determine whether a format of a Time Division Duplex (TDD) method used for communication with the end device (3a, 3b) in the communication network (1) satisfies the conditions of the request, c) in the event that the communication system (2) can fulfill the request of the end device (3a, 3b), providing communication for the end device (3a, 3b).3b) based on the conditions of the request.

3. Method according to claim 1 or 2, wherein the communication system (2) transmits a message to the terminal device (3a, 3b) if it cannot fulfill the request of the terminal device (3a, 3b) using any possible format of a time division duplex method.

4. Method according to one of the preceding claims, wherein the terminal device (3a, 3b) directs the request to the communication system (2) in anticipation of a communication task to be carried out.

5. Method according to any one of claims 1 to 3, wherein the terminal device (3a, 3b) directs the request to the communication system (2) in response to a failure to meet certain conditions of a communication already taking place between the terminal device (3a, 3b) and the communication system (2).

6. Method according to claim 1 or according to claim 1 and one of claims 3 to 5, wherein the conditions are a data rate, a latency or a jitter in the communication taking place between the terminal device (3a, 3b) and the communication system (2).

7. Method according to one of the preceding claims, wherein the request by the terminal device (3a, 3b) to the communication system (2) is made by specifying one or more 5QI values ​​by the terminal device (3a, 3b) and transmitting these 5QI values ​​to the communication system (2).

8. Method according to one of the preceding claims, wherein the communication system (2) provides the communication for the terminal device (3a, 3b) based on the Time Division Duplex (TDD) method with the requested format by specifying the Time Division Duplex (TDD) method with the requested format for communication for all connections within the communication network (1).

9. Method according to any one of claims 1 to 7, wherein the communication system (2) provides the communication for the terminal device (3a, 3b) based on the Time Division Duplex (TDD) method with the requested format by specifying the Time Division Duplex (TDD) method with the requested format for communication for a part of the connections within the communication network (1), in particular for one or more 5G Radio Units (10) or 5G Small Celis.

10. Method according to claim 9, wherein the communication system (2) provides communication for the terminal device (3a, 3b) based on the Time Division Duplex (TDD) method with provides the requested format by specifying the Time Division Duplex (TDD) procedure with the requested format for communication to the 5G Radio Unit(s) (10) or 5G Small Celis within whose radio range the terminal (3a, 3b) is located.

11. Method according to claim 9 or 10, wherein the communication system (2) checks whether the specification of the Time Division Duplex (TDD) method with the requested format would cause or actually cause transmission disturbances due to interference between the individual 5G Radio Units (10) or 5G Small Celis.

12. Method according to claim 10 or 11, wherein the 5G Radio Units (10) or the 5G Small Celis are operated in a radio frequency range of more than 24 gigahertz.

13. Method according to any one of claims 10 to 12, wherein the 5G Radio Units (10) or 5G Small Celis establish a connection to the terminal device (3a, 3b) via beamforming, wherein the beamforming is in particular limited to a security area which is twice the dimension of the terminal device (3a, 3b).

14. Method according to one of the preceding claims, wherein the communication system (2) provides the communication for the terminal device (3a, 3b) on the basis of the Time Division Duplex (TDD) method with the requested format by means of at least a temporary switch to another radio frequency range.

15. Communication system (2) for operating a wireless communication network (1), in particular based on 5G, in a technical plant, in particular a manufacturing or process plant, wherein the communication system (2) is configured to: a) receive a request directed to the communication system (2) from an end device (3a, 3b), wherein the request includes a format of a Time Division Duplex (TDD) method requested by the end device (3a, 3b) for communication in the 5G-based communication network (1); b) check the request of the end device (3a, 3b); and c) if the communication system (2) can fulfill the request of the end device (3a, 3b), provide communication for the end device (3a, 3b) based on the Time Division Duplex (TDD) method with the requested format.

16. Communication system (2) for operating a communication network (1), in particular based on 5G, in a technical plant, in particular a manufacturing or process plant, wherein the communication system (2) is configured to: a) receive a request directed from an end device (3a, 3b) to the communication system (2), wherein the request includes conditions for the execution of a communication task by the end device (3a, 3b); b) check the request of the end device (3a, 3b) to determine whether a format of a Time Division Duplex (TDD) procedure used for communication with the end device (3a, 3b) in the communication network meets the conditions of the request; c) if the communication system (2) can fulfill the request of the end device (3a, 3b), provide communication for the end device (3a, 3b) based on the conditions of the request.

17. Communication system (2) according to claim 15 or 16, comprising a core computing unit (6), a RAN computing unit (7), at least one radio unit (10) and / or at least one small cell.

18. Communication network (1) comprising a communication system (2) according to one of claims 15 to 17 and an end device (3a, 3b) which end device (3a, 3b) is configured to direct a request according to one of claims 1 to 17 to the communication system (2).

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