SE545962C2

SE545962C2 - Train ethernet network node for Gbit/s data transmission over 2-pair ethernet cable

Info

Publication number: SE545962C2
Application number: SE2051061A
Authority: SE
Inventors: Henrik Envall; Johan Furunäs-Åkesson
Original assignee: Westermo Network Tech Ab
Priority date: 2020-09-10
Filing date: 2020-09-10
Publication date: 2024-03-26
Also published as: WO2022055412A1; SE2051061A1; EP4211885A1

Abstract

Described are, among other things, a train ethemet network node (300) comprising a switch (320), at least two connectors (330, 332), and a transceiver unit (340, 342) for each connector. The connectors are adapted for connection to a 2-pair ethemet train network cable and each transceiver unit is adapted to transmit and receive data at at least 1 Gbit/s rate. A protection circuitry (350) is provided between the connectors and each transceiver unit.

Description

TECHNICAL FIELD The present disclosure relates to a network node. In particular the disclosure relates to a network node configured to serve an ethernet train network.

BACKGROUND Trains today are provided with an on-board ethernet network. The ethernet network in existing trains is utilizing an on-board 2-pair ethernet train network cable. The ethernet onboard trains can be configured differently depending on how the train itself is conf1gured.

A train is typically one or more consists that are connected together, or one or more locomotive pulling or pushing connected cars. A consist is typically a number of connected cars used as one single unit and that are seldom disconnected from each other. A car can be any type of single unit running on tracks such as a cab car, a coach, a restaurant, a locomotive etc.

The ethemet network typically extends all over the train from the front car to the rear car in order to provide data network services on-board the train. The data network services provided on the ethemet network on-board a train can be data for a wide range of data services such as Train Control and Management System (TCMS), which is a separate network for control traffic. Also, data for camera surveillance inside and outside of the cars can be sent and can also be sent to trackside control center. Typically, about four camera streams are selected by the driver to be shown on the driver°s desk. Further, network video recording in each consist can be sent to record all cameras. Data is often ofﬂoaded at depots.

Other data sent over the ethemet network include Passenger information display system/ Passenger audio system (PIDS/PAS) and Inforrnation shown on screens. For example, next station, what side to get off etc. Yet other data can be audio announcements from the driver (now often using Voice over IP (VOIP), Maintenance networks and Passenger internet access. The data load on the on-board ethernet network is constantly increasing.

The ethernet network on-board trains can be connected in different configurations. For example, a train backbone network can be provided that runs all along the train. This backbone ethernet network extending throughout the whole train is often configured in bus topology with aggregated connections provided.

In addition to the backbone network, the on-board train ethernet network can be supplemented by different local networks such as a consist network providing ethernet access within a consist of cars. The consist network can be connected to the backbone network. The consist network can typically be connected in a ring topology to provide redundancy with the consist network.

There is a constant desire to improve the perforrnance of the on-board train ethernet network and to enhance the capacity thereof.

SUMMARY It is an object of the present invention to provide an improved on-board ethemet network for trains. This object and /or others are obtained by the invention as set out in the appended claims.

As has been realized by the inventors, the need for increased ethemet capacity on-board trains needs to be addressed. A straight forward solution is to exchange the existing ethemet network with a high capacity Gbit/s network arrangement. This however has the drawback that new cables have to be installed in an environment where new installations are not easily carried out and the installation of new cables is therefore expected to be very costly indeed.

Instead, the inventors have realized that the existing cable network can be used for Gbit/ s data communication over ethernet if a new type of network nodes is developed and which can substitute the existing network nodes to increase the capacity on the existing network.

In accordance with the present invention, a train ethernet network node comprising a switch, at least two connectors, and a transceiver unit for each connector is provided. The connectors are adapted for connection to a 2-pair ethernet train network cable and each transceiver unit is adapted to transmit and receive data at at least l Gbit/ s rate. A protection circuitry is provided between the connectors and each transceiver unit. By thus providing a train ethernet network node that is able to transmit data at Gbit/ s speed and which is provided with protection circuitry to protect against hazardous voltage spikes that can arise within a train network, an exchange of data cables on-board trains can be avoided which in turn saves costs.

In accordance with one embodiment, the connectors are M12 connectors. Hereby the train ethernet network node can be directly connected to an existing 2-pair ethernet train network cable without the need for an adaptor or the like.

In accordance with one embodiment, the transceiver units are adapted to generate at least one full data rate and at least one first partial data rate. Hereby the train ethernet network node can be used in an environment with different types train ethemet network nodes supporting different network data rates.

In accordance with one embodiment, the transceiver units are adapted to generate at least a second partial data rate being lower than the first partial data rate. By providing support in the train ethemet network node for multiple data rates, the train ethemet network node can negotiate a suitable data rate with other train ethemet network nodes to achieve good performance regardless of which train ethemet network node that is connected at the other end of the 2-pair ethemet train network cable.

In accordance With one embodiment, a relay circuitry is provided where the relay circuitry is configured to provide a by-pass path over the train ethernet network node based on a predeterrnined event. Hereby data can be by-passed over the train ethernet network node which can be advantageous for example in the event of a power failure of the train ethernet network node.

In accordance with one embodiment, the relay circuitry is provided interconnected between the transceiver units and the protection circuitry. Hereby it is made possible to utilize radio frequency (RF) switches to provide a by-pass relay functionality, which can be advantageous to increase robustness and reduce reconfiguration time when the train ethernet network node enters/exits a by-pass mode.

The train ethemet network node in accordance with the present invention can advantageously be used in a train backbone node. However, it is also possible to configure the train ethemet network node as a consist network node. Hence, the same hardware can be used for both these types of train ethemet network nodes.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention will now be described in more detail by way of non-limiting examples and with reference to the accompanying drawings, in which: - Fig. l is a view illustrating a train, - Fig. 2 is a view illustrating a train ethemet network, and - Fig. 3 is a view illustrating a train ethemet network node in accordance with a first embodiment, - - Fig. 4 is a view illustrating a train ethemet network node in accordance with a second embodiment, DETAILED DESCRIPTION In the following a train ethernet network and in particular a Train ethernet network node will be described. In the figures, the same reference numerals designate identical or corresponding elements throughout the several figures. It will be appreciated that these figures are for illustration only and are not in any way restricting the scope of the invention. Also, it is possible to combine features from different described embodiments to meet specific implementation needs. In particular it is to be noted that while the components described are illustrated as separate components, it is also possible to combine different components into a single component. For example, the switch and the transceivers can be integrated as one component.

In Fig. 1 a train 100 with multiple cars 110 is depicted. The cars 110 can be any type of cars as exemplified above. The train can thus have any type of configuration and can comprise some combination of cars such as a cab car, a coach, a restaurant, a locomotive etc. Consists can also be part of or constitute the train. Within the train an ethemet network is arranged.

In Fig. 2 an exemplary ethemet network 200 for on-board train use is depicted. The ethemet network configuration of Fig. 2 is for illustration purpose only and any type of configuration can be envisaged to provide ethemet communication within the train 100. The ethemet network 200 typically comprises an Ethemet Train Backbone (ETB) 210. Also, a number of Ethemet Consist Network (ECN) 212, 214 can be provided.

The Ethemet Train Backbone 210 is typically arranged in a bus topology and typically runs all along the train to connect all or at least many of the cars / consists in the train. The Ethemet Consist Network 212, 214, when present, is typically arranged in a ring topology within a car/consist. The Ethemet Consist Network can however be configured in other topologies such as a star topology or a ladder topology.

Regardless of the topology, the ethernet network 200 comprises a number of train ethernet network nodes 300, 310. In Fig. 2 the ethernet network 200 comprises both train ethernet network node train backbone nodes 300 and consist network nodes 310. When the Train ethernet network nodes 300, 310 serves the ethernet network 200 it is as set out above desired to achieve a high data rate. In Fig. 3 an exemplary train ethernet network node 300 that can provide ethernet data traffic at Gbit/ s rate or above is depicted. It is to be noted that a consist network node 310 can be implemented in the same manner as the train ethemet network node The train ethemet network node 300 comprises a switch 320. The switch 320 is capable of switching Ethemet data at a high rate. In particular the switch 320 can switch data at a rate of at least 1 Gbit/ s or 2.5 Gbit / s or even 10 Gbit/s. The switch 320 can be any suitable high speed ethemet switch such as a Marvell 88E6390X or a switch with similar functionality.

The train ethemet network node 300 further comprises a first connector 330 and a second connector 332. The connectors 330, 332 are designed to connect to and thereby interface with a two pair ethemet train network cable. The connectors 330, 332 can advantageously be M12 connectors. Hereby the train ethemet network node 300 can be directly connected to existing, legacy, two pair ethemet train network cables without the need for any additional adaptors or the like. Each connector can be served by a corresponding transceiver unit 340, 342. The transceiver units 340, 342 interfaces with the switch 320 such that the data can be sent and received via the connectors 330, 332. The transceiver units 340, 342 are adapted to support the switch 320. The transceiver units 340, 342 hence are configured to transmit and receive data at at least 1 Gbit/s rate or the data rate at which the switch 320 can operate at.

Further, protection circuitry 350 is provided between the connectors and each transceiver unit. The protection circuitry is provided to protect the transceiver units and the switch from hazardous voltages and similar that could occur on the cable to which the train ethemet network node 300 is configured to be connected to.

The train ethernet network node 300, 310 as described herein is particularly targeting replacing existing train network nodes and thereby in an easy to install manner increase the data rate within the existing on-board ethernet network. It can then be envisaged that cars in the same train will have different types of ethernet network nodes 300, 310 supporting different data rates. In order to make communication possible between a high speed train ethemet network node and a legacy train ethemet network node operating at a lower data rate, the transceiver units 340, 342 can be adapted to generate at least one full data rate and at least one first partial data rate, the partial data rate being a fraction of the full data rate. Multiple different fractions of the full data rate can be supported by the train ethemet network nodes 300, 310. For example, the transceiver units can be adapted to generate at least a second partial data rate being lower than the first partial data rate.

The train ethemet network nodes 300, 310 can optionally also comprise a relay circuitry 360. The relay circuitry is configured to provide a by-pass path over the train ethemet network node 300 based on a predeterrnined event. For example, is power is lost to the train ethemet network node 300, it can be advantageous to by-pass the train ethemet network node such that data can be received by other train ethemet network nodes of the train ethemet network. This is particularly useful if the train ethemet network node is a train backbone node 300, but such a relay 360 may also be provided in a consist network node In Fig. 4, a train ethemet network node 300 in accordance with a second embodiment is depicted. The train ethemet network node 300 is similar to the first embodiment shown in Fig. 3. The train ethemet network node 300 in accordance with the second embodiment has a second relay circuitry 362. Thus, a first relay circuitry 360 can be provided interconnected between the connectors 330, 332 and the protection circuitry 350. Also, a second relay circuitry 362 can be provided interconnected between the transceiver units 340, 342 and the protection circuitry 350. The second relay circuitry 362 can be provided as a supplement or instead of the first relay circuitry 360. The second relay circuitry 362 can be implemented by radio frequency (RF) switches. This can improve the perforrnance of the protection circuitry 362 which is made faster and less costly. Also, the space required for implementation can be made smaller which is a major benefit since the train ethemet network node 300 preferably should be sized to fit where existing, legacy train ethemet network nodes now are located.

Using the train ethemet network nodes as described herein it will be possible to increase the data rate on-board trains without having to replace the entire infrastructure on-board the train. Instead only the ethemet network nodes need to be replaced.

Claims

l. Train ethernet network node (300, 310) coniprising - a switch (320), - at least two connectors (330, 332), - a transceiver unit (340, 342) for each connector (330, 332), fgf-šä-ifherein the connectors (330, 332) are adapted for connection to a 2-pair ethernet train network cable and where each transceiver unit (340, 342) is adapted to transniit and receive train ethernet data at at least l Gbit/ s rate and where protection circuitry (350) to protect against hazardous voltage spikes is provided between the connectors (330, 332) and the transceiver units (340, 342).
2. The train ethernet network node according to claini l, wherein the connectors (330, 332) are M l 2 connectors.
3. The train ethernet network node according to clain1 l or 2, wherein the transceiver units (340, 342) are adapted to generate at least one full data rate and at least one first partial data rate.
4. The train ethernet network node according to claini 3, wherein the transceiver units (340, 342) are adapted to generate at least a second partial data rate being lower than the first partial data rate.
5. The train ethernet network node according to any one of clainis l - 4, wherein a relay w circuitry (360, 362) is provided, where the relay circuitry configured to provide «\ of; based on a predeterrnined a by-pass path over the train ethernet network nodeí event.
6. The train ethernet network node according to c1ain1 5, wherein the predeterrnined event is power failure of the train ethernet network node (3 00, 310).
7. The train ethernet network node according to any one of c1ain1s 5 - 6, wherein the relay circuitry (3 62) is provided interconnected between the transceiver units (340, 342) and the protection circuitry (350).
8. The train ethernet network node according to any one of c1ain1s 1 - 7, wherein the train ethernet network node is a train backbone node (300).
9. The train ethernet network node according to any one of c1ain1s 1 - 7, wherein the train ethernet network node is a consist network node (310).