Communication bridge

Abstract

Communication bridge (130) for establishing a, preferably bidirectional, communication connection between a device (100), preferably an existing device, which preferably has a non-IP-based communication module (110), in particular a radio modem, in particular a 2G-based mobile modem, and an IP-based communication network (160), in particular a 4G or 5G mobile network, wherein the communication bridge has a first interface (120) for connecting the communication bridge to the device and a second interface (140) for connecting the communication bridge to the communication network, wherein the communication bridge has a processing unit (131) which is configured to convert non-IP-based communication, in particular AT communication, in particular AT command, which can be received from the device via the first interface, into IP-based communication, in particular a protocol message, which can be output to the communication network via the second interface.to translate and / or to translate IP-based communication, in particular protocol messages, received from the communication network via the second interface into non-IP-based communication, in particular AT communication, in particular AT response or unsolicited result code, that can be output to the device via the first interface.

Description

[0001] The invention relates to a communication bridge for establishing a, preferably bidirectional, communication connection between a device, preferably an existing device, comprising a non-IP-based communication module, in particular a radio modem, in particular a 2G-based mobile modem, and an IP-based communication network, in particular a 4G or 5G mobile network.

[0002] The present invention relates to the field of communication technology, in particular embedded communication systems and retrofit solutions for machine-to-machine (M2M) communication and the Internet of Things (IoT). More precisely, it provides a device that functions as a communication bridge, preferably wired and preferably bidirectional, between a device, in particular an existing device, with an outdated or legacy-based or non-IP-based communication module and a modern packet-switched IP (Internet Protocol)-based communication network. The invention specifically addresses the integration of older communication technologies, for example, 2G mobile communication modules according to the GSM standard (Global System for Mobile Communications), into current network infrastructures of the fourth or fifth generation of mobile communications, for example, 4G / LTE (Long Term Evolution) or 5G, as well as other IP networks.IP-based communication networks.

[0003] The invention has applications in numerous industries where long-life technical systems with older communication modules are in use. Examples include vehicles (automotive), industrial plants (e.g., manufacturing and process industries), energy systems (especially wind turbines and other supply infrastructure), railway technology (e.g., signaling and communication systems in trains and rail networks), medical technology (e.g., networked diagnostic or emergency systems), building technology (e.g., alarm systems or elevator emergency call systems), agriculture (e.g., agricultural machinery and environmental monitoring), and aviation and airport operations (e.g., ground-based sensors and communication systems). In all these areas, there is a need to seamlessly connect existing devices with outdated communication interfaces to modern IP networks without having to modify the existing equipment.The present invention is situated in the technical field of such communication bridges.

[0004] It is known from the state of the art that many existing systems and devices rely on older generation communication modules. Such legacy communication modules, for example, GSM / 2G radio modules or analog modems, are typically controlled via standardized command interfaces such as the Hayes command set. The Hayes command set, also known as the AT command set (from ATtention), comprises simple textual commands, such as ATD to dial a number, ATH to hang up, AT+CMGS to send an SMS, etc., which a host device uses to control a modem. Numerous technical systems in the aforementioned application areas have integrated such communication modules, ensuring data transmission, telemetry, remote maintenance, and alarm notification for many years.

[0005] However, telecommunications technology is advancing, and older network standards are being gradually phased out. In particular, second- and third-generation mobile networks (2G / GSM and 3G / UMTS) are being successively shut down worldwide or are about to be. In some countries, 2G networks have already been completely deactivated, while in others, including many European countries, specific shutdown dates have been set. For example, 3G networks in Europe have been largely out of service since 2021, and 2G / GSM networks are expected to be completely shut down between 2025 and 2028, depending on the network operator. It is therefore foreseeable that existing devices that communicate exclusively via 2G / GSM will no longer have connectivity in the near future. Even now, some operators have reduced the available 2G services, which limits the reliability of these connections.

[0006] The impending shutdown of legacy networks, or non-IP-based communication networks, presents operators with significant challenges. Many of the existing devices mentioned are embedded in critical infrastructures and often have a long service life remaining. Simply replacing these devices with new systems is frequently uneconomical or technically risky. Particularly in safety-critical sectors, such as rail, energy, medicine, and aviation, replacement involves substantial certification and testing efforts. Expensive systems have also been installed in industry and building management that, while functioning reliably, rely on outdated communication methods.

[0007] Several approaches from the state of the art are known to address this problem.

[0008] One approach involves upgrading the communication module. This approach consists of replacing the old 2G / GSM module with a modern one, such as an LTE / 4G modem. Specialized manufacturers offer corresponding drop-in replacements. These new modules are designed to replace the old modem, for example, with the same form factor and interface, and ideally, they should still understand the AT commands of the existing device. However, such a replacement requires access to the existing device's hardware, specifically opening the device, replacing the component, and possibly adjusting the configuration. Full compatibility of the new module is not always guaranteed. Differences in firmware, command set, or drivers can cause functional deviations.In many cases, the existing device is also a closed system whose manufacturer support has already expired, so that a module replacement can be difficult or even impossible.

[0009] Another approach involves using local cell towers or repeaters. The idea is to provide a local backup cell tower to trick the existing device into thinking it's connected to a 2G network. For example, a femtocell—a small, private base station—could be used to broadcast a 2G / GSM signal in the immediate vicinity. The existing device connects to this local cell, while the femtocell forwards the connection to the 4G / 5G network or the internet. Alternatively, GSM repeaters that amplify the signal from distant, still-active 2G cells are also being discussed. However, these solutions have significant drawbacks. Operating private cell towers generally requires frequency licenses, as licensed bands are used. Furthermore, there is a risk of interference with public networks. Technically, this effectively creates an isolated solution that requires complex configuration.A repeater, on the other hand, requires that a 2G signal still exists somewhere within range, which is unlikely to be the case in the foreseeable future. Overall, these wireless solutions are complex, expensive, and potentially unreliable.

[0010] Another approach involves gateway servers and centralized solutions.

[0011] The approach is based on central gateway servers. It is common to use special routers or edge devices with an AT modem emulator. In this scenario, a router is used in place of the GSM modem, which can receive AT commands from the existing device via its serial port. The router then establishes a connection to a counterpart or server via modern networks, particularly Ethernet and LTE. For example, some industrial routers can intercept AT dial-up commands (ATD...) and establish a virtual point-to-point connection over IP, such as via a VPN (Virtual Private Network), to a central server. The server, in turn, simulates a modem connection for the remote device. Such solutions make it possible to tunnel the dial-up mechanisms over IP networks. However, this often requires extensive infrastructure, such as a dedicated VPN server or cloud service, static IP addresses, or an entire secure network for managing the devices.Configuring and maintaining such systems requires expertise and modifications to the network architecture. This is not always practical for smaller operators or distributed installations.

[0012] In summary, none of the known solutions offer a simple, transparent, and universally applicable way to seamlessly connect an unmodified existing device with a legacy modem to modern IP networks. Either hardware modification, particularly module replacement, is necessary, or a complex external infrastructure, especially a dedicated radio cell, VPN gateway, etc., is required. In particular, no prior art discloses a solution that manages without creating a dedicated radio cell and without replacing the existing modem, while still providing the existing device with all its familiar communication functions. This is where the present invention comes in.

[0013] The present invention therefore aims to propose a communication bridge that enables the simple and cost-effective establishment of a communication connection, preferably bidirectional, between a device, preferably a non-IP-based or legacy-based or obsolete communication module, in particular a radio modem, in particular a 2G-based mobile modem, and an IP-based communication network, in particular a 4G or 5G mobile network or the Internet.

[0014] In particular, a communication bridge is described that allows the communication capability of an existing device with a legacy-based communication interface to be fully preserved or restored without requiring any modifications to the device itself. Specifically, a method is described for integrating an existing device, which, for example, can only communicate via a 2G / GSM module with an AT command set, into a modern IP-based communication network, such as 4G, 5G, or another data network. This integration preferably occurs in such a way that the existing device remains unchanged in both hardware and software; it should therefore be able to continue functioning exactly as before, without the need for firmware updates, hardware replacements, or protocol adjustments.

[0015] In particular, the system should be able to function without creating its own radio cell. This means that no local GSM / 2G base station or similar should need to be simulated. Likewise, the existing communication module of the existing device should not need to be removed or replaced with a different radio module. Instead, an external bridge solution should be created that can be connected between the existing device and the new network infrastructure.

[0016] In particular, a bidirectional communication bridge should be provided that can interpret AT commands sent by the existing device and translate them into equivalent protocol actions in the IP network, and conversely, translate incoming information or connection requests from the IP network back into AT communication understandable to the existing device. This should allow the existing device to be treated as if it still had its conventional connection, for example, a GSM network, even though a modern communication link, such as 4G / 5G or the internet, is actually being used. Specifically, all standard services such as call setup, data transfer, short messages (SMS), and, if applicable, voice communication should be made available in the new environment without altering the operating mode of the existing device.

[0017] This task is solved by a communication bridge with the features of claim 1.

[0018] The communication bridge according to the invention for establishing a, preferably bidirectional, communication connection between a device, preferably a non-IP-based or legacy-based communication module, in particular a radio modem, in particular a 2G-based mobile modem, and an IP-based communication network, in particular a 4G or 5G mobile network, or for coupling the device to the communication network, has a first interface for connecting the communication bridge to the device or establishing a communication connection with the legacy device and a second interface for connecting the communication bridge to the communication network or establishing a communication connection with the communication network, wherein the communication bridge has a processing unit which is configured to process a non-IP-based or legacy-based communication module, which can be obtained from the device via the first interface.to translate legacy-based communication, in particular AT communication, in particular AT command, into IP-based communication, in particular protocol message or a message based on an IP-based communication protocol, which can be output to the communication network via the second interface or for transmission to or via the communication network, and / or to translate IP-based communication, in particular protocol message or a message based on an IP-based communication protocol, which can be received from the communication network via the second interface, into non-IP-based or legacy-based communication, in particular AT communication, in particular AT response or unsolicited result code or another AT-compatible signal understandable by the device, which can be output to the device via the first interface.

[0019] The communication bridge acts as a translation gateway between non-IP (Internet Protocol)-based communication, in particular AT communication, which the device, especially an existing device, understands, and IP (Internet Protocol)-based communication, in particular an IP-based communication protocol or IP-based protocol message, which the IP-based communication network understands. By providing such a communication bridge between a non-IP-based device, especially an existing device, and an IP-based communication network, the device, especially an existing device, can be connected to the communication network via the communication bridge.A communication link can be established between the device, in particular existing equipment, and the communication network, enabling the device, in particular existing equipment, and the communication network to communicate with each other in a mutually understandable manner. The first and second interfaces allow the communication bridge to be connected to the device, in particular existing equipment, on the one hand, and to the communication network on the other, with the processing unit handling the actual translation between non-IP-based communication, in particular AT communication, and IP-based communication, in particular IP-based communication protocols or IP-based protocol messages.

[0020] The existing device may be a device that was originally intended for communication with a legacy communication network or an outdated or non-IP-based communication network, in particular a 2G mobile network, and is or was connected to the legacy communication network or outdated or non-IP-based communication network via a legacy-based or outdated or non-IP-based communication module of the existing device.

[0021] The processing unit can be configured to capture initial data, representing or describing AT communication, via the first interface, which can be provided and output by the existing device; to process this initial data by translating the AT communication into IP-based communication; to provide second data, representing or describing the IP-based communication; and to output this second data via the second interface. The second data can consist of IP packets.

[0022] The processing unit can be configured to process the initial data by extracting at least one piece of information, in particular the telephone number, address, and / or user information, from the AT command and embedding this information into the IP-based communication, in particular the communication protocol. The processing unit can include a parser component for decoding the AT command and extracting the relevant information or parameters.

[0023] The communication protocol can be an application-oriented protocol, in particular HTTP, HTTPS, MQTT, and / or a transport-oriented protocol, in particular TCP or UDP.

[0024] The processing unit can provide a translation layer to translate AT communication into IP-based communication and vice versa. Furthermore, the processing unit can provide a security layer to encrypt and / or authenticate the second data.

[0025] The invention solves the aforementioned problem by means of a communication bridge, preferably external and preferably wired, between the device, in particular an existing device, and the modern or IP-based communication network. The communication bridge can be designed as a separate device or module that can be connected to the device, in particular an existing device, via a suitable first interface. It can handle the complete protocol translation between the legacy-based communication of the existing device and the IP-based communication of the target network.In particular, the communication bridge can be configured to receive and interpret incoming AT commands from the device, especially existing equipment, and based on these, to trigger corresponding communication processes in the IP network, such as establishing a connection, data transmission, sending a message, receiving data and / or signals from the IP network, and converting these back into AT commands, AT responses, or data signals for the device, especially existing equipment. Communication can be handled in both directions in real time or virtually transparently, so that the device, especially existing equipment, appears to be communicating as usual via its old modem.

[0026] The communication bridge has a first interface, in particular a serial interface such as UART, RS-232, or similar, for connecting to the device, especially an existing device, through which the device, especially an existing device, can send its AT commands and receive data. Furthermore, the communication bridge has a second interface for connecting to the modern IP network. This second interface can be configured differently depending on the application. For example, a latest-generation cellular modem capable of connecting to a 4G or 5G network can be integrated. Alternatively or additionally, the communication bridge or the second interface can have an Ethernet port or a WLAN adapter to connect to an existing IP network, especially a LAN or WLAN.This second interface allows the communication bridge to access the internet or the respective IP communication network.

[0027] The core component of the communication bridge is a processing unit, such as a microcontroller or embedded processor with associated software or firmware, which can implement the abstraction and translation logic. This unit can be stateful and track the connection status of the communication. It can emulate a conventional modem for the device, especially existing equipment, by responding to AT commands with the expected responses, for example, OK, CONNECT, RING, NO CARRIER, etc. Simultaneously, it can initiate the corresponding actions in the IP network in the background. For example, the communication bridge can detect when the device, especially existing equipment, sends the connection establishment command (ATD followed by a phone number). The communication bridge interprets this phone number not as a real telephone number in the telephone network, but as an identifier for a destination endpoint in the IP network.It can use a pre-configured mapping table in which specific selected numbers can be assigned to corresponding IP addresses, hostnames, or URLs. The communication bridge can then establish a network connection to the target via its IP interface, such as a TCP / IP connection to a defined server or an end-to-end tunnel connection to a second communication bridge unit on the other side. Once the connection is established, the communication bridge can inform the device, especially an existing device, that the connection is now active by sending the standard modem response, for example, "CONNECT". From this moment on, all user data coming from the device, especially an existing device, can be forwarded to the IP network in real time via the communication bridge.Conversely, all data received via the IP connection can be transmitted directly and unchanged from the communication bridge to the device, especially existing equipment, as if it were coming from a modem.

[0028] All functions can be supported bidirectionally. This means that not only can connections initiated by the device, especially existing devices, be routed to the outside, but also that incoming connection attempts or messages from the network can be forwarded to the device, especially existing devices. For example, the communication bridge can detect an incoming call or virtual connection from the IP network and signal a ringing tone to the existing device, corresponding to a RING indicator in the AT interface. If the existing device accepts the "call," for example by sending the ATA command, the communication bridge can connect the other party and forward the incoming data to the device, especially existing devices. Text messages (SMS) can also be handled in both directions.If the device, especially an existing device, sends an SMS to a specific number using the AT command AT+CMGS, the communication bridge can intercept this action. It can then either send the SMS via the mobile network itself (if it is registered as a subscriber) or forward the message via an IP connection to an SMS server or messaging service that can handle delivery. Conversely, the bridge can receive incoming SMS messages, such as those sent via its own SIM card in a 4G / 5G modem, and notify the device, especially an existing device, of these messages. This notification can be made, for example, using an Unsolicited Result Code (URC) like +CMTI, or by making the message available in the message memory. The device, especially an existing device, can then read the message using the AT command AT+CMGR. This allows the device, especially an existing device, to retain its SMS-based functionality.

[0029] Advantageously, the communication bridge can offer additional enhancements beyond simple forwarding and translation functions. For example, one version can handle encrypted and authenticated communication within the IP network, such as establishing a VPN tunnel or using TLS (Transport Layer Security) for the data connection. This doesn't change anything for the device, especially existing equipment, but significantly increases the security and integrity of the transmitted data, which is particularly beneficial in critical infrastructures. The communication bridge can also perform protocol conversions. For instance, if the device, especially existing equipment, originally uses PPP (Point-to-Point Protocol) dial-up via modem, the communication bridge can receive this PPP data stream and terminate it locally to route the IP packets it contains into the network.The device, especially existing equipment, is still signaled that a successful connection has been established. Furthermore, the communication bridge can provide status information, for example to the operator or maintenance personnel, by collecting diagnostic messages, particularly 4G / 5G network signal strength, connection quality, errors, etc., and making them remotely accessible if necessary. It can also be designed to allow remote firmware updates to be installed to comply with new protocols or operator requirements.

[0030] Overall, a communication bridge is proposed that can mediate between a non-IP-based or legacy-based device, particularly existing equipment, and an IP network. The existing device can retain its legacy communication module and continue to communicate unchanged using the AT command set. The communication bridge can be externally integrated and comprise the hardware and software to translate the AT commands into IP network protocols in real time and vice versa. It requires no modifications to the existing device, does not use its own cell tower, but operates directly at the interface level. This ensures that an existing device, once installed, remains fully functional and can continue to perform its communication tasks even after the shutdown of previous networks. The lifespan and usability of such devices are significantly extended without the need for costly redesigns or modifications.Therefore, a transparent, bidirectional communication link can exist between the existing device and the IP-based network without requiring any hardware or software changes to the existing device.

[0031] The communication bridge thus enables a simple and cost-effective establishment of a, preferably bidirectional, communication connection between a device, preferably a non-IP-based or legacy-based communication module, in particular a radio modem, in particular a 2G-based mobile modem, and an IP-based communication network, in particular a 4G or 5G mobile network or the Internet.

[0032] In a preferred embodiment, the first interface can be implemented as a serial interface, preferably as an RS-232, RS-485, or UART interface. The first interface can therefore be a serial interface for data communication, preferably an RS-232, RS-485, or UART interface, for transmitting AT commands and data between the device, in particular an existing device, and the communication bridge. Furthermore, the first interface can be implemented as an SPI, CAN, LIN, or Automotive Ethernet interface.

[0033] In a preferred embodiment, the second interface can include an IP-based communication module, in particular a radio modem, and more preferably a 4G or 5G-based cellular modem with a SIM card, and / or an Ethernet port and / or a WAN port and / or a WLAN adapter. The second interface can therefore comprise a modern communication module capable of providing access to an IP-based network, in particular a fourth- or fifth-generation (4G / LTE or 5G) cellular module with a SIM card for registering with a cellular network, or alternatively / additionally an Ethernet or WAN port for connecting to a wired data network or the internet. Furthermore, the second interface can include a USB, M.2, or PCIe connector, in particular for connecting the communication module.

[0034] In a preferred embodiment, the processing unit can be configured to support an AT command set, wherein the AT command set preferably includes an AT command relating to establishing a connection to a telephone number, terminating a connection to a telephone number, sending a message, in particular a text message (SMS), to a telephone number, receiving a message, in particular a text message (SMS), and / or querying status information. The processing unit can thus be programmed to support the standardized Hayes command set (AT commands) as used by the legacy-based communication module of the existing device, including commands for establishing a connection, terminating a connection, sending and receiving messages, and querying status information.

[0035] In a preferred embodiment, the processing unit can be configured to translate an AT command received by the device via the first interface, concerning the establishment of a connection to a telephone number, into IP-based communication concerning the establishment of a connection, in particular a data connection, tunnel connection, or voice connection, via the communication network to another device that is in communication communication with the communication network, and to establish the connection between the device and the other device via the communication network. Preferably, the processing unit can be configured to signal the establishment of the connection to the device if it is successfully established. The connection can be established via the outputtable IP-based communication. The other device can be in direct or indirect communication communication with the communication network.For example, the communication network can be a mobile network, whereby the additional device can be in a communication connection with the mobile network directly, for example by dialing into the mobile network using a mobile modem of the additional device, or indirectly, for example via the internet connected to the mobile network by means of an internet gateway, to which the additional device can be connected. Upon receiving a dial-up command (ATD...) from the existing device, the processing unit can thus establish a tunnel or data connection via IP, which can functionally correspond to a wired connection, and signal a connection to the existing device after a successful IP connection has been established, for example by outputting "CONNECT".

[0036] In a preferred embodiment, when translating the AT command for establishing a connection to the telephone number into IP-based communication for establishing a connection to the other device, the telephone number contained in the AT command for establishing the connection to the telephone number can be translated, preferably using a configurable translation table, into an identifier for the other device, in particular an IP address, hostname, port, and / or URL. The processing unit can thus store a predefined translation table, mapping table, or mapping rules by means of which a telephone number or identifier specified in the dialing command can be assigned to a specific IP target, in particular an IP address, hostname, and / or port, to which the communication bridge can establish a connection with this dialing command.

[0037] In a preferred embodiment, the processing unit can be configured to translate an IP-based communication received from the communication network via the second interface, concerning a request to establish a connection between another device connected to the communication network and the device itself, into an unsolicited result code, in particular a ring tone or ring indicator. Preferably, the processing unit can be configured to establish a connection, in particular a data connection, between the other device and the device itself if the request is accepted by the device. The communication bridge can thus detect incoming connection attempts from the IP network and transmit them to the existing device in the form of a ring tone or ring indicator.a ring indicator signals, corresponding to a RING signal of the AT interface, whereupon, upon acceptance by the existing device (ATA), a data connection between the IP counterpart and the existing device can be established via the communication bridge.

[0038] In a preferred embodiment, data, in particular user data, can be transmitted bidirectionally via the communication bridge when a data connection is established between the device and the other device via the communication network.

[0039] In a preferred embodiment, the processing unit can be configured to translate an AT command received from the device via the first interface concerning the sending of a message, in particular a short message (SMS), to a telephone number into an IP-based message, in particular a short message (SMS), containing at least some content of the message and / or the telephone number, and to send it via the communication network to another device, in particular an end device or SMS gateway, which is in communication connection with the communication network, and / or to translate an IP-based message, in particular a short message (SMS), received from the communication network via the second interface into an unsolicited result code output to the device and preferably to respond to a query by the device, preferably by transmitting a corresponding AT command from the device to the processing unit.The communication bridge can therefore emulate short message (SMS) functions by allowing the processing unit to intercept AT commands for sending SMS messages (AT+CMGS and related commands) and either send the message text, including the recipient's number, as an SMS message via the integrated cellular module over the mobile network or forward it as an IP message to an SMS gateway server. Received SMS messages can either be received by the cellular module or received by the gateway and then forwarded to the processing unit, which can indicate the receipt of the SMS message to the existing device using AT-compliant messages, such as +CMTI or +CMT, and provide the content on request (AT+CMGR).

[0040] In a preferred embodiment, the communication bridge can have a message store, preferably virtual, for storing a plurality of IP-based messages, in particular short messages (SMS). The processing unit can thus manage a virtual message store that allows it to temporarily store multiple incoming SMS messages and provide the existing device with a corresponding list (AT+CMGL) upon request, in order to ensure compatibility with older SMS processes.

[0041] The communication bridge can also support voice connections by enabling the integrated 4G / 5G mobile module to initiate and maintain a voice call, particularly VoLTE, when a voice dialing command (ATD followed by a telephone number) is issued from the existing device. The communication bridge can optionally have audio inputs and outputs to transmit speech from a connected speech / listening unit of the existing device and to report incoming voice calls from the network to the existing device as a ring signal.

[0042] In a preferred embodiment, the communication bridge can therefore have at least one audio input and / or audio output.

[0043] In a preferred embodiment, the processing device can be configured to provide typical feedback and / or line signals, in particular dial tone, busy signal, ring back tone and / or standard result codes, in particular OK, ERROR, NO CARRIER and CONNECT, for a non-IP-based communication module, in particular a radio modem, in particular a 2G-based mobile modem. <speed>, to emulate. The processing unit can therefore emulate typical modem feedback and line signals, including dial tone, busy signal, ring back tone, and standard result codes such as OK, ERROR, NO CARRIER, CONNECT <speed>, in order to provide the existing device with expected behavior like a real telephone network / modem.

[0044] In a preferred embodiment, the processing device can be configured to protect data transmitted via the second interface using security protocols, in particular by establishing an encrypted connection, especially a VPN tunnel or a TLS-encrypted connection, between the device and another device connected to the communication network. The data transmitted via the second interface can thus be protected by security protocols, in particular by the communication bridge establishing an encrypted IP connection, for example a VPN tunnel or a TLS-encrypted connection, so that the information exchanged between the existing device and the remote device can be protected against eavesdropping and manipulation.

[0045] In a preferred embodiment, the communication bridge can have a configuration interface through which operating parameters can be set, in particular to configure the translation table or mapping table, access parameters, in particular APN, WLAN access, VPN certificate, for the communication network or other options, in particular activation of language support, wherein the configuration interface can preferably be implemented via USB, web interface or a special AT command extension.

[0046] In a preferred embodiment, the communication bridge can be designed as a standalone external device, preferably with a housing, and / or the communication bridge can be connected to the device by means of a cable and / or connector, and / or the communication bridge can be supplied with a voltage via the device or an external power supply unit, or can have a power supply unit for supplying the communication bridge with a voltage.

[0047] In an alternative embodiment, the communication bridge can be integrated into the device, preferably at a location originally intended for a non-IP-based communication module, in particular a radio modem, especially a 2G-based mobile modem. The communication bridge can thus be designed as an interchangeable module that can be inserted into a module slot or connector of the existing device, which was originally intended for a legacy communication module, for example a GSM module, so that the communication bridge can be integrated into the existing device in a mechanically and electrically compatible manner and can perform the functions described above internally.

[0048] The communication system according to the invention comprises a device, preferably a non-IP-based communication module, in particular a radio modem, in particular a 2G-based mobile communication modem, and a communication bridge as described above, wherein the communication bridge is connected to the existing device via a first interface of the communication bridge.

[0049] In a preferred embodiment, the device can include a control unit for providing non-IP-based communication, in particular AT communication, especially AT commands. The communication bridge can be connected to the device in such a way that the AT communication, originally intended for transmission to the non-IP-based communication module for its control, can also be transmitted by the control unit to the communication bridge. A connection between the control unit and the non-IP-based communication module can also be severed, so that the AT communication can no longer reach the non-IP-based communication module. The non-IP-based communication module can also be removed from the device. The communication bridge can then be integrated into the device at an installation location where the now-removed non-IP-based communication module was previously installed.

[0050] The device may include a microphone and / or a speaker.

[0051] The existing device could be, for example, a telematics device, especially for a vehicle.

[0052] The communication bridge can be used particularly in the context of connected car and remote services, telematics, location functions, remote diagnostics, fleet management, emergency call systems (eCall) and over-the-air services (OTA).

[0053] The communication bridge or communication system can be installed in a vehicle.

[0054] The communication bridge can meet the cybersecurity requirements of vehicles, in particular according to ISO / SAE 21434 and / or UNECE R 155 regulations. Furthermore, mechanisms for detecting anomalies or tampering attempts can be implemented.

[0055] The communication bridge can have an interface for service and diagnostic purposes, enabling vehicle diagnostics, for example via UDS (Unified Diagnostic Services) or proprietary diagnostic protocols, and / or software updates, especially over-the-air updates. This allows software updates (over-the-air updates) to be performed and operating data and fault codes to be read.

[0056] The communication bridge can be designed as an independent component, in particular a control unit, or be integrated into a component, in particular a vehicle gateway, domain controller or, in particular, a zonal control unit, of the vehicle.

[0057] The communication bridge may have a failover mechanism to switch to an alternative communication path, especially WLAN or Ethernet.

[0058] The communication bridge can be set up to receive operating and / or diagnostic data from a control unit of the vehicle and / or an external diagnostic system and / or to provide it to the control unit and / or the diagnostic system.

[0059] The communication bridge can be powered via the vehicle's electrical system, for example 12 V or 48 V, using a suitable DC / DC converter. EMC filters and protection circuits ensure compliance with automotive EMC requirements. The communication bridge can be designed to operate in an extended temperature range and withstand mechanical and vibration-related stresses within the vehicle.

[0060] The vehicle according to the invention, in particular a motor vehicle, comprises the communication system as described above. Preferably, the device is a control unit or telematics device. Preferably, the first interface is a CAN interface and / or a serial AT interface. Preferably, the communication bridge is connected to the device via a CAN bus. The communication bridge can be connected in parallel to or between the non-IP-based communication module, in particular a radio modem, especially a 2G-based mobile cellular modem. The communication bridge can be connected to the control unit, in particular in parallel to the non-IP-based communication module, in particular a radio modem, especially a 2G-based mobile cellular modem. Furthermore, the communication bridge can optionally have an audio interface, in particular for a microphone and / or a hands-free unit.The communication bridge can be designed to emulate the behavior of a 2G-based mobile modem towards the device and prevent system errors, diagnostic entries, or timeout conditions. The communication bridge can be integrated as a retrofit solution into an existing TCU architecture.

[0061] The communication bridge can be used for vehicles (automotive), industrial plants, for example manufacturing and process industries, energy plants, especially wind turbines and other supply infrastructure, railway technology, such as signaling and communication systems in trains and track networks, medical technology, for example networked diagnostic or emergency systems, building technology, such as alarm systems or elevator emergency call systems, agriculture, for example agricultural machinery and environmental monitoring, as well as aviation and airport operations, such as ground-based sensor technology and communication systems.

[0062] In a method for establishing a, preferably bidirectional, communication connection between a device, preferably comprising a non-IP-based communication module, in particular a radio modem, in particular a 2G-based mobile modem, and an IP-based communication network, in particular a 4G or 5G mobile network, by means of a communication bridge, the communication bridge can be connected to the device via a first interface of the communication bridge, wherein the communication bridge can be connected to the communication network via a second interface of the communication bridge, wherein by means of a processing unit of the communication bridge, non-IP-based communication, in particular AT communication, in particular AT command, received from the device via the first interface, is converted into communication via the second interface to the communication network for transmission to the device.IP-based communication, in particular a protocol message or a message based on an IP-based communication protocol, output via the communication network can be translated, and / or IP-based communication, in particular a protocol message or a message based on an IP-based communication protocol, received from the communication network via the second interface, can be translated into non-IP-based communication, in particular AT communication, in particular AT response or unsolicited result code, output via the first interface to the device or for transmission to the device.

[0063] In a preferred embodiment, when translating the AT command into IP-based communication, a command contained in the AT command can be translated into an action, particularly an equivalent one, in the communication network. The processing unit can be configured to execute the action, and preferably, the processing unit can be configured to transmit an AT response to the device in the event of successful execution of the action. The action can be executed as a result of the issued IP-based communication.

[0064] In a preferred embodiment, the command contained in the AT command relating to establishing or terminating a connection to a telephone number can be translated into an action relating to establishing or terminating a data connection, in particular a TCP / IP connection, enabling the transmission of user data, to another device in a communication connection with the communication network, wherein the processing unit can preferably be configured to monitor the status of the connection.

[0065] A preferred embodiment of the method may include the following process steps: a) Receiving an AT command transmitted by the existing device at the communication bridge; b) Interpreting the received AT command and determining a corresponding network action or action in the IP-based communication network; c) Execution of the identified network action or action by the communication bridge or processing unit, including sending protocol messages via one network interface or the second interface and, if necessary, establishing a data connection to a destination in the IP network; d) Upon successful execution of the network action or action: Sending an AT response to the existing device indicating success, for example a connection confirmation code or OK code; e) Subsequent forwarding of user data from the existing device via the communication bridge into the IP-based network and of received user data from the IP network to the existing device, for the duration of the established connection; f) Monitoring the connection status and, upon receiving a disconnect command from the existing device or upon termination of the network connection: closing the network connection and sending a corresponding message to the existing device, for example a disconnection identifier such as “NO CARRIER”.

[0066] In step b), when a dialing command (ATD) is issued by the existing device, a telephone number or identifier contained in the command can be evaluated and assigned to a specific IP destination, in particular address / port or remote party ID, based on a predefined assignment, whereupon in step c) a TCP / IP connection or a comparable communication channel can be established to this IP destination in order to establish the connection intended by the existing device.

[0067] The existing device can send an SMS message using AT commands, and the communication bridge can execute this process by capturing the SMS content and recipient identifier and either sending it as an SMS over the mobile network via a built-in cellular module or forwarding it as a packet-switched message to an external SMS delivery service. Conversely, incoming SMS messages can be received from the mobile network or service, converted into an AT-compliant format, and made available to the existing device.

[0068] The communication bridge can send a ring indicator to the existing device when a connection request is received from the IP-based network, in particular an incoming call or connection establishment by a remote party or another device, and, if the existing device accepts the connection establishment with a corresponding AT command, in particular a response to RING, establish a communication connection between the remote party or the other device in the IP network and the existing device, so that data exchange can then take place bidirectionally.

[0069] Further advantageous embodiments of the method result from the feature descriptions of the dependent claims relating back to claim 1.

[0070] Preferred embodiments of the invention are explained in more detail below with reference to the drawings.

[0071] They show: Fig. 1. A basic system architecture of a communication bridge in conjunction with an existing device and an IP-based communication network; Fig. 2 an exemplary flowchart of a protocol implementation and data transmission in the communication bridge (bidirectional data flow).

[0072] The Fig. Figure 1 shows a device or existing device 100 equipped with a legacy-based or non-IP-based communication module 110. This communication module 110 can, for example, be a conventional 2G / GSM modem controlled via AT commands. A communication bridge 130 is also shown, which is connected to the existing device 100 via a first interface 120 or a corresponding port of the communication bridge 130. A physical connection is established via interface 120. Depending on the existing device, interface 120 can be a serial interface, such as RS-232, RS-485, USB-UART, or TTL-level, as is common in many older devices for modem connections. The communication bridge 130 can be connected to the existing device 100 via a wired connection using a data line that can be connected to interface 120.Via the data line, the existing device 100, in particular a control unit of the existing device, can send AT commands and data to the communication bridge 130 and conversely receive AT responses or incoming data from or via the communication bridge 130.

[0073] Furthermore, the communication bridge 130 has a second interface 140. This interface is designed to connect the communication bridge 130 to a modern, IP-based communication network 160. Interface 140 includes a modern, IP-based communication module 150. Interface 140 can be integrated with the communication bridge 130, for example, by including a 4G / 5G mobile modem, WLAN adapter, or Ethernet controller permanently installed in the communication bridge 130. Alternatively, the communication bridge 130, or interface 140, could have a slot or port to which a separate communication module 150, such as an external LTE dongle or a WLAN adapter, can be connected. The communication network 160 could be, for example, a new-generation public mobile network, the internet, or a private IP network with which the existing device 100 is to exchange data via the communication bridge 130.The communication module 150 can, for example, register in the 4G / 5G mobile network, possibly using its own SIM card, or log into an existing LAN / WLAN to gain network access.

[0074] The communication bridge 130 also includes a processing unit 131, which implements a translation logic. The processing unit 131 comprises hardware, such as a microprocessor, memory, etc., as well as firmware or software with specific functions. It provides a kind of stateful protocol layer that can communicate with the existing device 100 via interface 120 according to the rules of the AT communication protocol, and with the communication network 160 via interface 140 according to the rules of modern IP communication protocols. This can be visualized as two virtual sides of the communication bridge 130: an "AT side" and an "IP side," between which the communication bridge 130 mediates.The processing unit 131 is therefore configured to translate non-IP-based communication, in particular AT communication, in particular AT command, received from the existing device 100 via interface 120 into IP-based communication, in particular protocol message, that can be output to the communication network 160 via interface 140, and / or to translate IP-based communication, in particular protocol message, received from the communication network via interface 140 into non-IP-based communication, in particular AT communication, in particular AT response or Unsolicited Result Code, that can be output to the existing device 100 via interface 120.

[0075] The existing device 100 and the communication module 110 can preferably remain unchanged. In the originally intended operation, the existing device 100, or a control unit of the existing device 100, would typically send AT commands to the communication module 110, for example, to establish a connection. However, in this case, these AT commands are intercepted by the communication bridge 130. They may not even be processed by the communication module 110 itself, because the communication bridge 130 communicates on its behalf. In practice, the communication module 110 could be deactivated, or the communication bridge 130 could be connected in parallel to a communication bus, depending on the implementation. The communication bridge 130 emulates the functions of the original legacy communication network or communication module 110 with respect to the existing device 100. A double arrow 170 or...180 indicates a bidirectional transferability of data, in particular describing AT communication or IP-based communication, between the existing device 100 and the communication bridge 130 or between the communication bridge 130 and the communication network 160.

[0076] The following are various application examples for the communication bridge 130, whereby for the sake of simplicity all the application examples refer to the Fig. 1. will be described.

[0077] The Communication Bridge 130 can be used in the automotive sector. Specifically, it can be installed in a vehicle. The existing device 100 can be a telematics unit for a motor vehicle. This telematics unit may originally be designed to send data to a control center via a GSM communication module, for example, for fleet management or emergency call systems. The existing device 100 can remain installed in the vehicle unchanged. The Communication Bridge 130 can be connected externally to the existing device 100. The existing device 100 continues to communicate with the control center via the Communication Bridge 130, but no longer via 2G / GSM radio; instead, it uses a modern 4G / 5G mobile network. The Communication Bridge 130 in the vehicle can receive the AT commands from the telematics unit and send data to the backend or control center via its integrated 4G or 5G modem.No modifications are necessary for the vehicle and its systems, yet connectivity is guaranteed even after the 2G network is switched off.

[0078] The Communication Bridge 130 can be used for industrial plants. The existing device 100 can be an industrial control or monitoring unit, such as a PLC (Programmable Logic Controller) or a Remote Terminal Unit, within an industrial plant. This unit has a legacy-based communication module 110, which previously transmitted data, such as production data and fault messages, to a central system via GSM mobile network or modem. The Communication Bridge 130 can be integrated into a control cabinet as a retrofit component and connected, for example, to the PLC's serial interface. Using the integrated modern communication module 150, such as an LTE router, the Communication Bridge 130 can forward messages from the PLC to the IP-based communication network 160, for example, to a factory control room or a cloud. The existing PLC remains unaffected.The communication bridge 130 handles external communication. This makes it possible to integrate even older industrial plants into networked systems within the framework of Industry 4.0 without replacing the control hardware.

[0079] The Communication Bridge 130 can be used in a power generation plant, specifically at a wind turbine. Modern wind turbines have remote monitoring systems, older models of which are often connected via GSM / GPRS. The existing device 100 can be a wind turbine controller with a legacy-based communication module 110, which can be connected to an IP-based communication network 160 via the Communication Bridge 130. The Communication Bridge 130 can be retrofitted, for example, in a wind turbine tower. It can receive the AT commands from the plant controller, such as when it wants to send measurement data or establish a connection, and transmit the data to a control center of the wind farm operator via, for example, a robust 4G communication network. This allows even remote wind turbines to continue reliably providing status messages and performance data after the 2G network is switched off.No changes to the plant controller are required. Only the external communication infrastructure is replaced by the communication bridge 130.

[0080] The Communication Bridge 130 can be used in railway technology. The existing device 100 could be a signaling or interlocking system on a railway line that originally communicated via a GSM-R or GSM-based modem for status transmission or remote control. By adding the Communication Bridge 130, this system can continue to send data to a railway operations center. The Communication Bridge 130 can be connected to an existing communication port of a signal and forward information via a modern Communication Network 160. The Communication Network 160 can be an LTE-based railway communication network or a dedicated railway IP network. Despite modernized transmission technology, such as 5G for railway operations, the old system can remain unchanged and continue to send its commands and signals as usual. The Communication Bridge 130 handles the protocol conversion and ensures interoperability.

[0081] The Communication Bridge 130 can be used in medical technology, for example, with a patient monitoring device or a mobile emergency device as an existing device 100 that previously communicated via GSM. Such devices may regularly send vital data to a hospital or trigger an alarm via SMS / call in an emergency. This function would cease after the old networks are shut down. The Communication Bridge 130, which is connected upstream of the existing device 100, allows communication to be maintained. The existing device 100 can initiate an emergency call using AT commands. The Communication Bridge 130 can convert the AT command into an IP message or a VoLTE call in the communication network 160, for example, a hospital intranet or mobile network. The existing medical device 100 does not need to be modified for this.The communication bridge 130 can also be built so small that it fits inside the housing of the existing device 100 or functions as an adapter. This makes medical alarm systems future-proof, which is particularly important for certified medical devices, as their software / hardware can hardly be modified.

[0082] The Communication Bridge 130 can be used in building automation systems. The existing device 100 can be an alarm system or an elevator emergency call system in a building. Many such systems still use analog telephone lines or GSM modules to send a message to a security service or emergency call center in case of an alarm. The system can remain installed in the building without modification. The Communication Bridge 130 can be connected to its communication output, for example, to an alarm dialer port. In the event of an incident, the system dials a number as usual. The Communication Bridge 130 can detect this and forward the alarm to an emergency call center via the Communication Network 160, for example, as a data message or as an automated VoIP call.An entire building with numerous such systems can be made fit for the future by simply retrofitting communication bridges 130 to the respective existing devices 100, without, for example, having to replace all alarm systems.

[0083] The Communication Bridge 130 can be used in agriculture. The existing device 100 could be an agricultural sensor system or a machine control unit in a field. For example, if an irrigation system or tractor were to send status data via a GSM module or receive control commands via SMS, this would be problematic after the 2G network is discontinued. The Communication Bridge 130, which can be connected to such an existing device 100, allows agricultural equipment to continue operating in a networked manner. The Communication Bridge 130 can be robustly designed and connect the existing device 100 to a farm computer or a cloud platform via an available communication network 160, such as a 4G mobile network with wide coverage. Even in harsh outdoor environments, the Communication Bridge 130 can be designed to be weatherproof and, if necessary, powered by solar energy or vehicle power to ensure reliable communication.The Communication Bridge 130 can also facilitate digital transformation in the agricultural sector by allowing older equipment to continue to be used.

[0084] The Communication Bridge 130 can be used in aviation and airports. For example, the existing device 100 could be a ground sensor system, such as a weather station or an airfield lighting controller, which previously transmitted data to the control center via a GSM modem at an airport. By installing a Communication Bridge 130, this system can continue to operate, as the Communication Bridge 130 establishes a connection via a modern Communication Network 160, such as an airport's own IP network or a 5G campus network. Similarly, the existing device 100 could be an aircraft system, such as an older onboard communication device, that exchanges data with another device on board or on the ground. Instead of undertaking expensive avionics upgrades, a certified Communication Bridge 130 could be integrated into the existing system to enable communication via satellite IP or a new ground network.In all these cases, the core hardware of the existing device 100 can remain unchanged, while the communication bridge 130 can ensure compatibility with modern networks.

[0085] The Fig. Figure 2 illustrates the bidirectional protocol conversion process within the communication bridge 130. A schematic sequence diagram depicts the timeline of bidirectional communication via the communication bridge 130. In step 1, the communication bridge 130 receives an AT command, for example ATD, from the existing device 100. In step 2, the communication bridge 130 processes or analyzes the AT command. In step 3, the communication bridge 130, or the processing unit 131, translates the AT command into IP-based communication, specifically a protocol message. The processing unit 131 can, for example, use a translation table to look up a destination address of a remote device or prepare a network connection.In step 4, the communication bridge 130 establishes a connection, for example a TCP Connect, to a remote device via the communication network 160, in particular by initiating IP-based communication. In step 5, the communication bridge 130 sends a response, for example a CONNECT signal, to the existing device 100. In step 6 or step 7, data is transferred from the existing device 100 via the communication network 160 to the remote device or from the remote device to the existing device 100, respectively. Additionally, the... Fig. 2 at least partially also represent the receipt of a message or a call, for example, when a call with a connection request is received at communication bridge 130, which communication bridge 130 then forwards as a RING to the existing device 100. Overall, the Fig. 2, how the communication bridge 130 acts as an intermediary by receiving commands and data from one domain, converting or translating them and passing them on to the other domain, in both directions, i.e. bidirectionally.

[0086] The following describes the functionality of the communication bridge 130 and its protocol implementation, particularly with reference to the Fig. 2, explained in more detail using an example.

[0087] In a first scenario, an outgoing connection is initiated from the existing device 100, for example, a data call or a data connection. The existing device 100 sends the AT command ATD12345 via its AT interface. In the context of a classic modem, this input means: Dial the number "12345". The communication bridge 130 receives (see step 1) this AT command and interprets (see step 2) the sequence "12345" according to its configuration. In this example, it is assumed that the sequence "12345" does not represent a real telephone number, but is understood as an identifier for a specific server or destination in IP. Using a translation table, which can optionally be stored in the communication bridge 130, the processing unit 131 translates (see step 3) the sequence "12345" into, for example, an IP address "10.1.1.50" of a remote site.a further device that is in a communication connection with communication network 160. The communication bridge 130 then initiates a connection setup via communication network 160 using the communication module 150, specifically by sending an IP-based protocol message to the remote device (see step 4). A TCP connection to the IP address 10.1.1.50 on a predefined port can be opened, or a special tunnel protocol can be started to establish a virtual serial connection. In any case, the communication bridge 130 attempts to establish a network session with the desired remote device. As soon as the connection has been successfully established on the IP side, for example, by the remote device, especially a remote server or endpoint, accepting the request, the communication bridge 130 signals this to the existing device 100 (see step 5).This occurs when the communication bridge 130 on the AT side issues the standard connection indicator, typically the message "CONNECT". The existing device 100 then "believes" it has established a circuit-switched connection, such as a modem connection, to the remote device as usual. From this point on, the existing device 100 sends user data—for example, in the case of a modem, this could be a PPP negotiation or application data—via interface 120. The communication bridge 130 receives these incoming data packets or streams and forwards them transparently over the already established IP connection (see step 6). Depending on the implementation, the communication bridge 130 can use different approaches here. For example, it can operate a fully transparent tunnel that transmits byte by byte unchanged.Then, at the other end, a second communication bridge or special software would potentially receive the data. Alternatively, the communication bridge 130 itself can function as a communication endpoint and, for example, perform protocol termination, such as ending PPP and routing the contained IP packets into the network. Both variants serve the purpose of bringing the information coming from the existing device 100 into the IP network. Incoming data from the remote end is handled analogously in the reverse direction (see step 7). The data received via the communication module 150 enters the communication bridge 130, which outputs it to the existing device 100 via interface 120. For the existing device 100, the data appears as if it came directly from a conventional modem. The existing device 100 processes it further with its application logic.

[0088] Another aspect is the termination of the connection. If the existing device 100 wants to close the connection, for example by ATH or by lowering the control line, the communication bridge 130 detects this request and closes the IP connection accordingly, confirming the termination to the existing device 100, for example with a "NO CARRIER" or "OK" message. Conversely, if the remote device in the IP network disconnects or loses the connection, the communication bridge 130 registers this, for example by closing a TCP socket, and informs the existing device 100 with an appropriate message, typically "NO CARRIER" to indicate that the connection is interrupted. The communication bridge 130 then returns to a standby state in which it can receive new commands.

[0089] In addition to the described connection setup for data transfers, the communication bridge 130 preferably also fully supports other AT functionalities: Telephony / Voice Connections: Should the existing device 100 initiate voice calls, for example with ATD followed by a real telephone number, as opposed to a data call, the communication bridge 130 can also react. In this case, communication module 150 would make a voice call via the 4G / 5G mobile network. In particular, it can establish a VoLTE (Voice over LTE) connection, or via fallback if supported. With suitable hardware, the Communication Bridge 130 can also forward audio data. Since many purely technical devices do not use a voice function, this is optional. However, it can be relevant in vehicle emergency call systems (eCall) or elevator emergency call systems. The Communication Bridge 130 can then have audio inputs and / or audio outputs to connect a microphone / speaker of the existing device 100, or it can forward digitally encoded audio data accordingly. In any case, it would signal the connection setup to the existing device 100 and handle the voice connection analogously to the data connection.

[0090] Text Messages (SMS): SMS commands are supported. The Communication Bridge 130 recognizes commands such as AT+CMGS (send SMS) or AT+CMGL / AT+CMGR (read SMS) and can maintain an internal virtual message memory. For sending, either the Communication Module 150 or the mobile communication module is used directly, which then sends the SMS in the 4G network either via SMS-over-LTE or 2G fallback, or the content is sent via an IP message to a central server that delivers the SMS, for example, via the HTTP(S) API of a messaging service. Upon receipt, the Communication Bridge 130 registers incoming SMS messages either via the mobile communication module or receives them from a server and temporarily stores them in order to then either spontaneously send a +CMTI: (New SMS Indication) message to the existing device 100 or make them available upon request.This allows an existing device 100 to continue operating in SMS alert mode, even if network operators only provide SMS via IMS in the 4G network. The communication bridge 130 completely abstracts these details.

[0091] USSD and other AT commands: Some devices use USSD codes or network-specific commands, for example, AT+CUSD for Unstructured Supplementary Service Data. The Communication Bridge 130 can be configured to either reject such commands, return an error message, or, where possible, implement them via alternative services. For example, frequently used USSD functions could be replaced by web service requests executed by the Communication Bridge 130 to achieve a similar result. In many cases, however, USSD is specific to cellular networks and is omitted if, for example, IP services are used instead.

[0092] Network registration and status commands: Commands such as AT+CREG? (network registration status) or AT+CSQ (signal quality) may be queried periodically by the existing device. The communication bridge 130 can respond to such commands by returning its own status values. For example, AT+CSQ can respond with a simulated signal strength value, which is either fixed or, if the communication module 150 is a cellular module, reflects the actual signal quality of the 4G / 5G modem. AT+CREG? can always display "registered" as long as the communication bridge 130 is online in the IP network. This prevents the existing device 100 from being confused by a perceived network loss. Generally, the communication bridge 130 is operated in such a way that it suggests a stable, always available network connection to the existing device 100.

[0093] The invention is not limited to mobile networks. While a primary application is the migration from 2G / GSM to 4G / 5G, the communication bridge 130 can, in principle, translate any type of legacy communication link to an IP link. For example, an analog telephone dialer, particularly a PSTN modem, could be connected to the communication bridge 130 via a suitable interface. The communication bridge 130 can then detect dialing attempts and establish the connection via VoIP (Voice over IP) or a telephony server. Similarly, an older radio with an AT-like interface can be integrated. The invention provides a general translation gateway that is modularly adaptable to various protocols.

[0094] For practical use, the Communication Bridge 130 can be implemented in different hardware forms. In one version, it is a small external device that is mounted, for example, near the existing Device 100. It then has the necessary connections, such as a serial port for device connection and, if required, an antenna or an Ethernet port for the IP network. This version is particularly suitable for retrofits where access to the interface of the existing Device 100 is available. For example, a cable that originally connected to the GSM modem is now plugged into the Communication Bridge 130. In another version, the Communication Bridge 130 can also be implemented as a plug-in module, for example, in the form of a circuit board or card that is inserted into the device slot in place of an existing GSM modem. Many industrial devices have modular communication slots.The Communication Bridge 130 can be implemented as an LTE module that fits into this slot but internally contains the translation function. Such a module would electrically transmit the same signals as the old modem (AT command set to the host) but communicate externally with a modern network. This modular variant is similar to a hardware replacement but has the advantage that the protocol translation intelligence is integrated into the module and is more universally compatible; that is, it is more than just a modem replacement, but a configurable gateway.

[0095] Integrating multiple existing devices (100) is also possible. A single communication bridge (130) can have multiple serial ports to connect several existing devices (100) to a network. It is also conceivable that multiple communication bridges (130) are distributed across the field, each connecting existing devices (100) at specific points. On the server side, central software can then manage the connections from all communication bridges (130). In any case, the concept also enables point-to-multipoint scenarios. Many remote existing devices (100), each equipped with communication bridges (130), can connect to a central control system, similar to traditional dial-up connections to a control room, except that it now operates via IP. Typical protocols in such applications, for example, SCADA systems in energy technology, can continue to be used, as the communication bridges (130) maintain transparent data flow.

[0096] In conclusion, it should be emphasized that the Communication Bridge 130 can be designed as a plug-and-play solution. After a one-time configuration of the parameters, such as the mapping table of phone numbers to IP addresses, access data for the mobile network or WLAN, etc., it can operate autonomously. The existing Device 100 requires no update and is completely unaware that the infrastructure has changed. This transparency and ease of retrofitting existing systems represents a significant advantage over conventional solutions. Reference symbol list 100 existing units 110 Communication module 120 interface 130 Communication bridge 140 interface 150 Communication module 160 Communication network 170 Double Arrow 180 double arrow Step 1 Step 2 Step 3 Step 4 Step 5 Step 6 Step 7< / speed> < / speed>

Claims

[1] Communication bridge (130) for establishing a, preferably bidirectional, communication connection between a device (100), preferably an existing device, which preferably has a non-IP-based communication module (110), in particular a radio modem, in particular a 2G-based mobile modem, and an IP-based communication network (160), in particular a 4G or 5G mobile network, wherein the communication bridge has a first interface (120) for connecting the communication bridge to the device and a second interface (140) for connecting the communication bridge to the communication network, wherein the communication bridge has a processing unit (131) which is configured to convert non-IP-based communication, in particular AT communication, in particular AT command, which can be received from the device via the first interface, into IP-based communication which can be output to the communication network via the second interface,in particular, to translate protocol messages and / or to translate IP-based communication, in particular protocol messages, received from the communication network via the second interface into non-IP-based communication, in particular AT communication, in particular AT response or unsolicited result code, that can be output to the device via the first interface. [2] Communication bridge according to claim 1, characterized by , that the first interface (120) is implemented as a serial interface, preferably as an RS-232, RS-485, CAN or UART interface. [3] Communication bridge according to claim 1 or 2, characterized by , that the second interface (140) has an IP-based communication module (150), in particular a radio modem, in particular preferably a 4G or 5G-based mobile modem having a SIM card, and / or an Ethernet port and / or WAN port and / or WLAN adapter. [4] Communication bridge according to one of the preceding claims, characterized by , that the processing device (131) is configured to support an AT command set, wherein the AT command set preferably includes an AT command relating to establishing a connection to a telephone number, terminating a connection to a telephone number, sending a message, in particular a short message (SMS), to a telephone number, receiving a message, in particular a short message (SMS), and / or querying status information. [5] Communication bridge according to one of the preceding claims, characterized by, that the processing unit (131) is configured to translate an AT command received from the device (100) via the first interface (120) concerning the establishment of a connection to a telephone number into an IP-based communication concerning the establishment of a connection, in particular a data connection, tunnel connection or voice connection, via the communication network (160) to another device that is in a communication connection with the communication network and to establish the connection between the device and the other device via the communication network, wherein preferably the processing unit is configured to signal the establishment of the connection to the device in the event of a successful connection. [6] Communication bridge according to claim 5, characterized by, that when translating the AT command concerning the establishment of the connection to the telephone number into IP-based communication concerning the establishment of the connection to the further device, the telephone number contained in the AT command concerning the establishment of the connection to the telephone number is translated, using a translation table, preferably configurable, into an identifier identifying the further device, in particular IP address, hostname, port and / or URL. [7] Communication bridge according to one of the preceding claims, characterized by, that the processing device (131) is configured to translate an IP-based communication received from the communication network (160) via the second interface (140) concerning a request to establish a connection between another device in a communication connection with the communication network and the device via the communication network into an unsolicited result code, in particular a ring signal or ring indicator, wherein preferably the processing device is configured to establish a connection, in particular a data connection, between the other device and the device if the request is accepted by the device (100). [8] Communication bridge according to one of claims 5 to 7, characterized by, that when a data connection is established via the communication network (160) between the device (100) and the other device via the communication bridge (130), data, in particular user data, can be transmitted bidirectionally. [9] Communication bridge according to one of the preceding claims, characterized by, that the processing unit (131) is configured to translate an AT command received from the device (100) via the first interface (120) concerning the sending of a message, in particular a short message (SMS), to a telephone number into an IP-based message, in particular a short message (SMS), containing at least some content of the message and / or the telephone number, and to send it via the communication network (160) to another device, in particular an end device or SMS gateway, which is in a communication connection with the communication network, and / or to translate an IP-based message, in particular a short message (SMS), received from the communication network via the second interface into an unsolicited result code output to the device and preferably to respond to a query by the device, preferably by transmitting a corresponding AT command from the device to the processing unit,to provide the device with at least some content from the IP-based message. [10] Communication bridge according to claim 9, characterized by , that the communication bridge (130) has a, preferably virtual, message storage for storing a plurality of IP-based messages, in particular short messages (SMS). [11] Communication bridge according to one of the preceding claims, characterized by that the communication bridge (130) has at least one audio input and / or audio output. [12] Communication bridge according to one of the preceding claims, characterized bythat the processing unit (131) is configured to provide typical feedback and / or line signals, in particular dial tone, busy signal, ring back tone and / or standard result codes, in particular OK, ERROR, NO CARRIER and CONNECT, for a non-IP-based communication module (110), in particular a radio modem, in particular a 2G-based mobile modem. <speed>, to emulate. [13] Communication bridge according to one of the preceding claims, characterized by , that the processing unit (131) is equipped to protect data transferable via the second interface (150) by means of security protocols, in particular by establishing an encrypted connection, in particular a VPN tunnel or a TLS encrypted connection, between the device (100) and another device connected to the communication network (160) via the communication network. [14] Communication bridge according to one of the preceding claims, characterized by that the communication bridge (130) has a configuration interface via which operating parameters can be set, in particular to configure a translation table, access parameters, in particular APN, WLAN access, VPN certificate, for the communication network (160) or other options, in particular activation of language support, wherein the configuration interface is preferably implemented via USB, web interface or a special AT command extension. [15] Communication bridge according to one of the preceding claims, characterized by , that the communication bridge (130) is designed as an independent external device, preferably with a housing and / or the communication bridge can be connected to the device (100) by means of a cable and / or connector and / or the communication bridge can be supplied with a voltage via the device or an external power supply device or has a power supply device for supplying the communication bridge with a voltage. [16] Communication bridge according to any one of claims 1 to 14, characterized by that the communication bridge (130) can be integrated into the device (100), preferably at an installation location originally intended for a non-IP-based communication module (110), in particular a radio modem, in particular a 2G-based mobile modem. [17] Communication system comprising a device (100), in particular an existing device, comprising a communication module (110), preferably a non-IP-based communication module, in particular a radio modem, in particular a 2G-based mobile modem, and a communication bridge (130) according to one of the preceding claims, wherein the communication bridge is connected to the existing device via a first interface (120) of the communication bridge. [18] Communication system according to claim 17, characterized by , that the device (100) has a control unit for providing non-IP-based communication, in particular AT communication, in particular AT command. [19] Vehicle, in particular motor vehicle, comprising the communication system according to claim 17 or 18, wherein preferably the device (100) is a control unit or telematics device, wherein preferably the first interface (120) is a CAN interface and / or serial AT interface, wherein preferably the communication bridge (130) is connected to the device via a CAN bus.< / speed>

Images