EP1886893A1 - Method for transmitting data in a rail vehicle, and rail vehicle therefor - Google Patents

Abstract

Rail vehicle (1) comprises vehicle units with coupling devices (5) connected to an information bus (2) of the vehicle units for transferring broadband data signals from or to the bus. An independent claim is also included for a method for transferring data in a rail vehicle. Preferred Features: Each coupling device has a deep pass filter having a typical limiting frequency of less than 1 MHz and is switched on the side of the coupling device facing away from an information bus coupling. Each coupling device is operated in repeater mode.

Description

Technical area

The invention relates to a rail vehicle with one or more vehicle units, each comprising one or more cars, wherein at least one vehicle unit comprises a designed for a narrow-band data transmission, unit-internal information bus, and the at least one vehicle unit at one of its ends an information bus coupling comprises, by means of which unit-internal information bus this at least one vehicle unit with a unit-internal information bus another vehicle unit to a unit-comprehensive information bus is interconnected. Furthermore, the invention relates to a method for data transmission in such a rail vehicle.

State of the art

It is known to incorporate communication systems in vehicles such as trains, trams and similar vehicles having multiple, interconnected vehicle units. These communication systems are typically used to e.g. B. on a display to indicate the name of the next stop, through announcements in the car of the vehicle speakers to pass messages to the passengers or the vehicle escort, but also for control purposes such as opening, closing and locking the doors or the inputs and Turn off the lights in each car.

For such applications, only relatively small amounts of data need to be transferred. Only a few pulses are required for the door or light control and a bandwidth of a few kHz (kilo heart) is sufficient for the transmission of voice data. The known communication systems are accordingly designed only for the transmission of data signals with a bandwidth up to a few hundred kHz (narrowband data transmission).

Such a narrow-band data transmission in trains typically has a corresponding information bus installed. An example of such an information bus is the UIC (union international des chemins de fer), which typically comprises a plurality of insulated copper conductors, each having a cross-sectional area of the order of 1 square millimeter. These cables typically have an EMC shielding comprising all conductors, a protective sheath as well as possibly one or more intermediate layers of plastic strips. One of the line pairs of this UIC cable is used for example for service messages, another for announcements to the passengers. Other lines are used as control lines for lighting control or in rail vehicles with more than one locomotive or railcar also for the multi-traction control. When two cars equipped with such an information bus are coupled together to form a train or part of a train, the information buses of the two cars either automatically or - for example, in older vehicles - manually by means of appropriate couplings connected together. In this way, a generally extending through the entire rail vehicle information bus. However, it may also happen that one or more cars do not have such an information bus.

The inter-carriage clutches of the information bus, the most common ramifications (the cables are often split at the ends of a car), the devices connected to the bus (such as clocked electronic circuits), the fact that the individual pairs of such information busses are typical are not separately shielded and other factors, however, affect the transmission characteristics of this information bus in a negative way. Such information buses have at high frequencies, for example, a poor symmetry, are usually not finished clean at the respective ends and often even have a total reflection and correspondingly inhomogeneous characteristic impedance as well as a high transit time dispersion. As a rule, such information busses also result in frequency-selective and time-selective disturbances. All of these characteristics generally limit the achievable data rates greatly.

In addition to the information bus designed for the narrow-band data transmission, communication systems are further known in such rail vehicles, which permit broadband data transmission within a wagon. Such communication systems include, for example, an in-car Ethernet that includes one or more Ethernet switches. As a car in the broader sense to be understood below compositions of cars. Such compositions are distinguished by the fact that they comprise several carriages, but that the individual carriages of a composition are usually no longer separated once they have been put together. A single car or such a car composition is referred to below as a vehicle unit. Accordingly, it is possible to interconnect the wideband communication systems of the individual carriages of a composition by means of appropriate wiring to one another to a cart-wide broadband communication system, so that in all cars a composition accessible broadband communication system such. B. an Ethernet is available.

In individual cars, which are often separated and coupled together again with other cars to train, there is usually no technical way to connect the broadband communication systems of the car directly. Consequently, there is no direct, cross-carriage, broadband data transmission from one car to the next or between two car compositions.

Presentation of the invention

The object of the invention is to provide a rail vehicle belonging to the technical field mentioned at the outset or a method for data transmission which permits broadband data transmission both within a vehicle unit and between two or more vehicle units coupled to one another.

The solution of the problem is defined by the features of claim 1. In a rail vehicle having one or more vehicle units each comprising one or more cars, at least one vehicle unit having an in-vehicle information bus (hereinafter referred to as unit-internal) designed for narrow-band data transmission and the at least one vehicle unit having an information bus connector at one of its ends The at least one vehicle unit according to the invention comprises at least one coupling device which is connected to the unit-internal information bus of the at least one vehicle unit and with which the at least one vehicle unit can be interconnected with a unit-internal information bus of another vehicle unit to form a unit-spanning information bus which broadband data signals can be decoupled from the unit-internal information bus or into the unit-internal information bus ei can be coupled and transmitted via the unit-internal information bus.

The term narrow-band data transmission is understood below to mean a transmission of data signals whose frequency spectrum is below 1 MHz. Accordingly, the term broadband data transmission is used hereinafter to describe a transmission of data signals whose frequency spectrum is above 1 MHz, typically between 2 MHz and 34 MHz, understood. Analogously, the term narrow-band data signal is intended to encompass those data signals which, on the one hand, have a narrow bandwidth and, on the other hand, whose frequency spectrum is below 1 MHz. Accordingly, the term broadband data signal should include those data signals which on the one hand have a high bandwidth and whose frequency spectrum on the other hand is above 1 MHz.

Over the existing information buses narrowband data signals are transmitted in a known manner, which typically include analog, low-frequency signals or narrow-band digital signals each having a frequency spectrum below 1 MHz. Since the information bus designed for narrow-band data transmission is now also used according to the invention for the transmission of broadband data signals with a frequency spectrum above 1 MHz, the information bus can be optimally utilized for broadband data transmission.

In this way, a passenger can be offered modern multimedia applications in which it is necessary to transmit broadband data signals with data rates of over 100 kbit / s, whose frequency spectrums are in the frequency range of a few hundred kHz to a few MHz. Such applications include, for example, Internet access, which allows the passenger to "surf" the Internet while traveling by vehicle. Another possible application is, for example, that the passenger can individually select a film from a centrally stored selection of films and display them on a personal monitor.

In order to be able to realize a broadband data transmission via such a transmission medium as the information bus described above, the transmission technology used must be able to co-exist in particular with the already existing applications of the information bus. Ie. the transmission technology used may only use the frequency range above 1 MHz, in particular those between 2 MHz and 34 MHz, for signal transmission. It should also have efficient channel coding with strong error correction to correct for transmission errors caused by the high noise levels. In addition, it is advantageous if you have an adaptive, carrier-selective bit loading allows, which adapts to the channel conditions at the respective Trägerfreuqenz so that can be used efficiently in multi-carrier modulation method of the frequency and time-selective channel. In other modulation methods, in particular in Eintragmodulationsverfahren devices should be provided for adaptive channel equalization.

Known transmission technologies such as Ethernet do not meet these conditions and are therefore not suitable for the transmission of broadband data signals over the information bus. An example of a transmission technology that meets these conditions is Powerline technology, which was originally developed to transmit data at high data rates over power grids. The Powerline technology is very robust in terms of all kinds of interference and imperfections in the transmission medium and is therefore preferably used to realize the transmission of the broadband data signals via the information bus in rail vehicles. Since this technology uses the frequency range above 1 MHz, it also coexists well with the methods used in the prior art for data transmission over the information bus in the frequency range below 1 MHz.

While new vehicle units can be easily and cheaply equipped with appropriate coupling devices (consisting of a modem part, a bus coupler and a data interface), even existing vehicles can be retrofitted easily and inexpensively with such coupling devices. The bus couplers or modems can both standalone units as well as an integral part of other vehicle components such. B. an existing vehicle communication and / or information system.

On the one hand, data transmission within a vehicle unit can be achieved by connecting a plurality of coupling devices at different locations within a vehicle unit to the information bus.

In a preferred embodiment of the rail vehicle, however, at least one vehicle unit comprises a separate, unit-internal communication device for transmitting data signals, in particular a communication device for a Broadband data transmission of data signals with a frequency spectrum above 1 MHz. In the vehicle units, for example, an Ethernet network can be installed. The unit-internal communication device can also be a narrowband network, z. B. be a network according to RS 232. Such a unit-internal communication device typically comprises a transmission medium and one or more data processing or data terminals which are connected to the transmission medium. However, as the unit-internal communication device, a transmission medium suitable for data transmission should also be understood below without permanently connected data processing or data terminals. For example, a single Ethernet cable laid in the vehicle unit should also be subsumed under this term.

According to this preferred embodiment of the invention, the coupling device is now connected to the unit-internal communication device and the data signals can be coupled in and out of the unit-internal information bus with the coupling device from the unit-internal communication device and can be coupled into the unit-internal communication device.

How the data signals are coupled into and out of the information bus is irrelevant here. It is both a capacitive, as well as an inductive coupling possible.

• die für die Übertragung der Datensignale verwendeten Leiter bzw. Leiterpaare sind ungeschirmt,
• für Frequenzen über 1 MHz weist es eine schlechte Symmetrie auf,
• es umfasst Verzweigungen, d. h. der Informationsbus ist typischerweise am Ende einer Fahrzeugeinheit gesplittet,
• es weist an seinen Enden eine Totalreflexion auf,
• es weist inhomogene charakteristische Leitungsimpedanzen (Wellenwiderstand) auf,
• er weist eine hohe Laufzeitdispersion auf.

As already mentioned, the information bus is a transmission medium, which typically has at least one of the following properties:

• the conductors or conductor pairs used for the transmission of the data signals are unshielded,
• for frequencies above 1 MHz, it has poor symmetry,
• it includes branches, ie the information bus is typically split at the end of a vehicle unit,
• it has a total reflection at its ends,
• it has inhomogeneous characteristic line impedances (characteristic impedance),
• he has a high transit time dispersion.

In a further preferred embodiment of the invention, the rail vehicle comprises two adjacent vehicle units, each comprising an in-unit communication device, a unit-internal information bus and an information bus coupling at one of its ends, the two unit information buses being interconnected with these information bus clutches to form a cross-unit information bus.

In a mode referred to as a bridge mode, the broadband data signals between the in-unit communication devices of the two vehicle units with one for the used, in-unit communication device are used to transmit the data signals within a vehicle unit or between two vehicle units transparent point-to-point transmission over the cross-unit information bus. In this mode, the two in-unit communication devices of the two vehicle units are virtually connected together to form a single unit-spanning communication device.

In order to keep the distance between the coupling devices forming the bridge as small as possible, the coupling devices in this case are each preferably arranged at that end of a vehicle unit with the information bus coupling. Thereby, the attenuation of the signals in the transmission between the coupling devices can be kept small and higher data rates can be achieved.

Advantageously, the coupling devices in this case each comprise a low-pass filter with a cut-off frequency of typically less than 1 MHz. This low-pass filter is connected on a side facing away from the information bus coupling side of the coupling device in the unit-internal information bus and thus suppresses the spread of transmitted on the information bus, broadband data signals in this direction, ie seen from the coupling device in the opposite direction of the information bus coupling. At the same time, these low-pass filters also keep high-frequency interference away from the coupling devices, which originate on the other side of the coupling device and could adversely affect the broadband data transmission.

However, under certain circumstances, these additional low-pass filters can also be omitted since the natural attenuation of the information bus is sufficient to suppress the transmission of the data signals between two coupling devices of the same vehicle unit, which is undesired in bridge mode.

Further, in another preferred embodiment of the invention, the coupling devices may be operated in a mode called bus mode. Also for operation in this mode, the rail vehicle comprises two vehicle units, each comprising an in-unit information bus and at one of its ends an information bus coupling, the two unit-internal information buses being interconnected with the information bus couplings to form a cross-unit information bus. In this mode of operation, the two vehicle units continuous information bus used quasi as a cross-unit backbone over which the broadband data signals are transmitted with a point-to-multipoint transmission. In this mode, usually only a single coupling device per vehicle unit is required and for the cross-unit data transmission, unlike the bridge mode no additional communication device must be provided.

However, in a further advantageous embodiment of the invention, the two vehicle units each have, in addition to the information bus, an in-unit communication device (as already described above), wherein typically a data processing device is connected to such an in-unit communication device. In this case, the coupling devices of the two vehicle units are each also connected to this unit-internal communication device and the broadband data signals are transmitted via the coupling devices from or to such a data processing device.

In short rail vehicles or if the natural attenuation of the information bus is very low, the coupled from a coupling device in the cross-unit information bus data signals from any other, also connected to this cross-unit information bus coupling device can be received. However, if the coupled-in data signal is attenuated too much, in a further preferred embodiment of the invention, one or more of the coupling devices are operated in a repeater mode. However, this mode is not used in place of the bus mode but in addition to the bus mode. In this mode, a data signal from a first coupling device is coupled into the information bus, received by a coupling device operated in the repeater mode, regenerated by this and coupled back into the information bus and transmitted to a next coupling device. In this data signals can be transmitted from the first to the next coupling device, even if the attenuation of a transmitted signal would be too large to bridge the distance between these two coupling devices directly.

The object of the invention to provide a method for transmitting data in a rail vehicle with one or more vehicle units, each comprising one or more cars and each one designed for a narrow-band data transmission, unit-internal information bus is defined by the features of claim 9.

According to the invention, the broadband data signals are transmitted via the unit-internal information bus by being coupled to a first coupling device of one of the vehicle units in the unit-internal information bus, transmitted via the unit-internal information bus and coupled to a second coupling device of one of the vehicle units from the unit-internal information bus.

Since the frequency spectrum of the broadband data signals to be transmitted is above 1 MHz, they can be transmitted via the information bus simultaneously with the narrowband data signals whose frequency spectrum is below 1 MHz, without these having a negative influence on each other.

In this way, it is possible to realize a broadband data transmission over the information bus unit-internally in a vehicle unit equipped with one or more coupling devices.

In a preferred embodiment of the invention, the broadband data signals are transmitted in a rail vehicle with two vehicle units, wherein the unit-internal information buses of the two vehicle units are interconnected by means of information bus couplings of the vehicle units to form a unit-spanning information bus. In this case, the broadband data signals are transmitted from a first coupling device of a first vehicle unit via the unit-overlapping information bus to a second coupling device of a second vehicle unit.

Ie. the broadband data signals are transmitted across the information bus couplings from one vehicle unit to the other vehicle unit.

In another, preferred embodiment variant of the invention, the two vehicle units each comprise a unit-internal communication device as already described above, wherein the broadband data signals are transmitted between these two communication devices by receiving with a first coupling device of one of the two vehicle units from their unit-internal communication device via the cross-unit information bus, d. H. via the information bus of the two vehicle units connecting information bus clutches, transmitted to the second coupling device and supplied from a second coupling device of the second vehicle unit whose unit-internal communication device.

As already described above, the unit-internal communication devices of the two vehicle units in a preferred embodiment the invention interconnected by means of the coupling devices to a cross-unit communication network by the coupling devices operated in a bridge mode and the broadband data signals between the unit-internal communication devices of the two vehicle units are transmitted by means of a point-to-point transmission.

In a further preferred embodiment of the invention, the coupling devices are used to transmit data redundantly. Ie. the information content of a narrowband data signal which is transmitted via the information bus between the vehicle units is transmitted for the purpose of redundancy by means of the coupling devices at least partially and substantially simultaneously as part of a broadband data signal via the unitary information bus between the vehicle units.

As a result, the probability that the information content to be transmitted actually reaches its destination can be increased without the corresponding data having to be transmitted several times in succession as a narrow-band data signal via the information bus. The information content of the narrowband data signals is transmitted even with bad contacts of the information bus couplings, thanks to the capacitance and the mutual inductance between the wires serving the transmission of the narrowband data signal and the other wires of the information bus. At the high frequencies of the broadband data signal, these capacitances and mutual inductances become effective.

As already mentioned above, in a preferred embodiment of the invention, the coupling devices are operated in a bus mode and the broadband data signals are transmitted by means of a point-to-multipoint transmission via the unit-spanning information bus.

As also mentioned earlier, in a further preferred variant of the invention, at least one coupling device is operated in a repeater mode in that the broadband data signals of a first coupling device of at least one of these Coupling device to be received, regenerated and transmitted to a next coupling device.

In yet another preferred embodiment of the invention in which the coupling devices are operated in bus mode, the coupling devices are used to determine the order of the vehicle units. This is done by first the signal attenuation between the coupling devices is determined when a data signal is transmitted between them. As a function of this signal attenuation, the order of the vehicle units is subsequently determined.

For this purpose, in particular the reception levels of the broadband data signals emitted by the other coupling devices are measured by a specific coupling device, of which in each case the transmission levels are known. From the known transmission level and the measured reception level, the attenuation is determined on the information bus between the two coupling devices concerned. Assuming that a coupling device of the measuring coupling device is the farther away, the greater this attenuation fails, the order of the coupling devices and hence also that of the associated vehicle units can be determined.

From the following detailed description and the totality of the claims, further advantageous embodiments and feature combinations of the invention result.

Brief description of the drawings

Fig. 1

Ein erfindungsgemässes Schienenfahrzeug mit einer Fahrzeugeinheit, welche einen einzelnen Wagen umfasst;

Fig. 2

Ein erfindungsgemässes Schienenfahrzeug mit einer Fahrzeugeinheit, welche eine aus drei Wagen bestehende Wagenkomposition umfasst;

Fig. 3

eine schematische Darstellung der Fahrzeugeinheit aus Fig. 2;

Fig. 4

ein erfindungsgemässes Schienenfahrzeug mit mehreren, jeweils einen Wagen umfassenden Fahrzeugeinheiten, bei welchem die Koppelvorrichtungen im Bridge-Modus betrieben werden;

Fig. 5

eine schematische Darstellung eines Schaltplanes des Buskopplers einer Koppelvorrichtung;

Fig. 6

ein erfindungsgemässes Schienenfahrzeug mit mehreren, aneinandergekoppelten, jeweils mehrere Wagen umfassenden Fahrzeugeinheiten, bei welchem die Koppelvorrichtungen im Bridge-Modus betrieben werden;

Fig. 7

eine schematische Darstellung des einheitsübergreifenden Kommunikationsnetzes des Schienenfahrzeugs aus Fig. 6 und

Fig. 8

ein erfindungsgemässes Schienenfahrzeug mit mehreren, jeweils einen Wagen umfassenden Fahrzeugeinheiten, bei welchem die Koppelvorrichtungen im Bus-Modus betrieben werden.

The drawings used to explain the embodiment show:

Fig. 1

A railway vehicle according to the invention comprising a vehicle unit comprising a single car;

Fig. 2

A railway vehicle according to the invention with a vehicle unit, which comprises a car composition consisting of three carriages;

Fig. 3

a schematic representation of the vehicle unit of Fig. 2;

Fig. 4

a railway vehicle according to the invention with a plurality of vehicle units, each comprising a carriage, in which the coupling devices are operated in bridge mode;

Fig. 5

a schematic representation of a circuit diagram of the bus coupler of a coupling device;

Fig. 6

a railway vehicle according to the invention with a plurality of vehicle units, coupled to each other, each comprising a plurality of cars, in which the coupling devices are operated in bridge mode;

Fig. 7

a schematic representation of the unitary communication network of the rail vehicle of Fig. 6 and

Fig. 8

a railway vehicle according to the invention with a plurality of vehicle units, each comprising a carriage, in which the coupling devices are operated in bus mode.

Basically, the same parts are provided with the same reference numerals in the figures.

Ways to carry out the invention

1 shows a vehicle unit according to the invention, in this case a single railroad car 1, which comprises an information bus 2 with information bus couplings 3, a carriage-internal communication network 4 and a coupling device 5. The coupling device 5 is connected both to the information bus 2, as well as to the communication network 4. However, the information bus couplings 3 should not be confused with the car couplings (not shown), with which several such railway cars 1 are coupled together. However, it is possible that the information bus clutches 3 are integrated into these car clutches, as it were, so that the information buses of different carriages are automatically connected together to form an information wide bus when two such railway carriages 1 are coupled to each other. The information bus 2 is physically, for example, a so-called Zugbuskabel, for example, a UIC Zugbuskabel- Such UIC cable is available in different versions, each with more or fewer wires / cable pairs. While the wires of these UIC cables are typically not shielded separately, there are also designs which include one or more separately shielded pairs of conductors. Such UIC cables are used, for example, for the so-called "integrated on-board information systems" (IBIS). If a separately shielded pair of conductors is present, it is preferably used for the transmission of the broadband data signals.

The coupling device 5 comprises not only a bus coupler, the responce the data signals from or in the information bus 2, respectively. but also typically a modem part and an interface to the communication network 4. It may also include other parts and interfaces. The communication network 4 may in itself be any network via which data signals can be transmitted. In this case, it is an Ethernet network, wherein the coupling device 5 comprises an Ethernet interface, via which it is connected with a corresponding Ethernet cable to the communication network 4, which includes, for example, one or more (not shown) Ethernet switches ,

With the aid of the coupling device 5, broadband data whose frequency range is above 1 MHz can now be coupled into the information bus 2, transmitted via this and decoupled from the information bus 2 with another coupling device of another railway carriage.

For carrying out the invention, the communication network 4 can also be omitted. In fact, for certain applications it is sufficient if the broadband data signals are transmitted via the information bus 2, coupled out of the information bus 2 by a coupling device 5 and optionally processed and sent to another one Coupling be forwarded without the data thus transmitted would have to be transmitted via the communication network 4 to another device.

Further, it is also possible that instead of the communication network 4, a single data processing or data terminal such as a computer, a display / screen, a video camera or similar device is provided which via a corresponding communication connection (wired or wireless) to the coupling device 5 is connectable.

Fig. 2 shows a railway vehicle according to the invention, which comprises a composition 6, which consists of three firmly coupled to each carriage 6.1, 6.2, 6.3. Although the individual carriages 6.1, 6.2, 6.3 of such a composition 6 can certainly be separated from each other, this is typically not done, so that the individual communication networks 4.1, 4.2, 4.3 are firmly connected to a single, composition-wide communication network 4, as shown schematically in Fig. 3 is shown.

4 shows a further rail vehicle according to the invention with a plurality of vehicle units, ie the individual cars 1.1, 1.2, 1.3 and a locomotive 7 (or also a railcar) which are coupled together to form a train. The locomotive 7 comprises a coupling device 5.1 connected to its information bus 2, and each carriage 3.1, 1.2, 1.3 comprises two coupling devices 5.2 and 5.3, 5.4 and 5.5, and 5.6 and 5.7, which are arranged at each end of the carriages 1.1, 1_2, 1_3. These coupling devices 5.1 - 5.7 are operated in bridge mode. The data signals are transmitted only between two adjacent coupling devices, ie between the coupling devices 5.1 and 5.2, the coupling devices 5.3 and 5.4, the coupling devices 5.5 and 5.6, etc. via the information bus 2 to each of the communication networks 4.1, 4.2, 4.3 adjacent vehicle units with each other connect. These pairs of coupling devices each form a bridge between the corresponding communication networks 4.1, 4.2, 4.3, via which the signals between the individual communication networks 4.1, 4.2, 4.3 are transmitted transparently.

The signals are therefore transmitted only on the short sections of the information bus 2 between two coupling devices of adjacent cars, which allows high data rates, because the channel attenuation on these short connectors low and the signal-to-noise ratio is correspondingly high.

The coupling devices 5.1-5.7 are in this case each with a low-pass filter, hereinafter also referred to simply as a filter equipped, which are each arranged on that side of a coupling device 5.1-5.7, which the information bus 3 of the corresponding car 1.1, 1.2, 1.3 or locomotive is opposite. These filters serve to suppress the transmission of the broadband data signals within a carriage 1.2, 13, 1.4 via the information bus 2 to the respective other coupling device of this car 1.2, 1.3, 1.4. The lying between these low-pass filters piece of information bus 2 each car 1.2, 1.3, 1.4 is therefore shown in dashed lines.

In the locomotive 7, the Ethernet interface of the coupling device 5.1 is not as in the car 1.1, 1.2, 1.3 with an Ethernet switch (not shown), but directly to a data processing device, in this case a server 8, connected, from which For example, large amounts of data can be transmitted to the individual Wgen 1.1, 1.2, 1.3. The server 8 is connected, for example, via a (not shown) connection to the Internet, which allows a passenger in one of the car 1.1, 1_2, 1.3, to surf the Internet. Or the server 8 includes a large memory on which the films mentioned above are stored, from where they can download a passenger in a car 1.1, 1.2, 1.3 and, as mentioned, on a personal (or common) screen.

5, the bus coupler 9 is shown, as it is installed, for example, in the coupling devices 5.1-5.7. The bus coupler 9 is designed for inductive coupling of the data signals in and out of the information bus 2 and has a low inductance. It comprises a first information bus terminal 10 with two terminals 10.1, 10.2, a second information bus terminal 11 with two terminals 11.1, 11.2, a modem interface 16 with two terminals 16.1, 16.2, a coupling circuit 12, a Tiepfassfilter 14 and between the coupling circuit 12 and the modem interface 16 switched transient protection 15. The bus coupler 9 is in each case in the Information bus 2 turned on. The conductor pair of the information bus 2 used for the transmission of the broadband data signals is separated for this purpose, and the two ends of this pair of conductors are respectively connected to the bus coupler 9 at one of the two information bus connections 10, 11. This separation of the information bus is of course preferably between two optionally existing anyway plugs so that the cable does not need to be damaged.

For the inductive coupling, the coupling circuit 12 comprises two transformers 13, each with two windings 13.1, 13.2. The two terminals 10.1, 10.2 of the first information bus terminal 10 are connected to one end of the windings 13.1 and the two other ends of the windings 13.1 are connected via the low-pass filter 14 to the second information bus terminal 11. In each case one end of the windings 13.2 of both transformers 13 are connected directly to one another and the respective other end of the windings 13.2 is connected to one of the connections 16.1, 16.2 of the modem interface 16.

The low-pass filter 14 each comprises an inductance 14.1 in the connecting lines between the ends of the windings 13.1 to the terminals 11.1, 11.2 of the second information bus terminal 11 and a respective capacitance 14.2 between the two ends of the windings 13.1 and between the two terminals 11.1, 11.2 of the second Informationsbusanschlusses 11. The inductance of the two inductors 14.1, for example, each 10 μH. The capacity of the two capacitances 14.2 is, for example, 10 nF in each case.

In order to reduce crosstalk via the core capacitances and mutual inductances, other filter elements can also be provided in the other wires of the information bus. It should be mentioned with regard to the capacitance 14.2 between the two ends of the windings 13.1 that this not only belongs to the low-pass filter, but is also part of the coupling circuit and virtually forms an HF short-circuit there.

The transient protection 15 comprises four diodes 15.1, 15.2, 15.3, 15.4 in a full bridge circuit and a Schottky diode 15.5 whose anode is connected to the anodes of the diodes 15.1, 15.2 and whose cathode is connected to the cathodes of the diodes 15.3, 15.4 is. The cathodes of the diode 15.1 and 15.2 are respectively combined with the anodes of the diodes 15.3 and 15.4 and connected on the one hand to the free end of each of the windings 13.2 as on the other hand with one of the terminals 16.1, 16.2 of the modem interface 16.

This low-pass filter results in a characteristic curve in which low-frequency signals below 100 kHz pass undamped through the filter, but at a frequency of 1.5 MHz already results in an attenuation of 40 dB.

For the transmission of the broadband data signals, as already mentioned above, a transmission technology should be used which has some specific properties so that it can coexist with the existing narrowband data transmission over the information bus. For example, for the transmission of broadband data signals, it should only use the frequency range above 1 MHz, should have efficient channel coding with a strong error correction, and should allow for efficient channel utilization as far as possible an adaptive, carrier-selective bit loading.

An example of such a transmission technology are the so-called PLC (power line communication) technologies developed for high bit-rate data transmission via power supply networks.

Modulation:

OFDM mit 4 bis 1024 QAM-modulierten Unterträgern

Kanalcodierung

concatenated Reed-Solomon + 4D Trellis

Betriebsfrequenzbereich:

2 bis 34 MHz, wobei das Sendespektrum beliebig maskierbar ist,

Sendeleistung:

ca. -50 d8m/Hz (was in der vollen Bandbreite ca. 200 mW ergibt),

Kanaladaptivität:

bit loading 2 bis 10 bit pro Unterträger

spektrale Effizienz:

maximal 7 bit/Hz (netto)

Datendurchsatz:

maximal 205 Mbit/s (auf dem physical layer)

Netto-Datendurchsatz:

maximal ca. 120 Mbit/s (TCP)

Leitungsdämpfung:

ca. 40 dB bei maximalem Datendurchsatz (falls keine Störungen vorhanden sind und ohne Spektrumsmaskierung) ca. 70 dB bei 20% des maximalen Durchsatzes

Such a PLC transmission technology is therefore preferably used to implement the invention. The data transfer takes place z. B. with a coded OFDM (orthogonal frequency division multiplexing) transmission method with up to 1000 subcarriers in a frequency grid of a few kHz. Here, each subcarrier QAM (quadrature amplitude modulation) is modulated with a symbol alphabet (bit loading), which is adapted to the specific channel conditions at the respective sub-frequency. This allows optimal utilization of the frequency- and time-selective channel and also allows a sharply defined spectrum masking, for example to suppress EMV (electromagnetic compatibility) - critical frequency ranges. The technical data of this technology are in detail:

Modulation:

OFDM with 4 to 1024 QAM modulated subcarriers

channel coding

concatenated Reed-Solomon + 4D Trellis

Operating frequency range:

2 to 34 MHz, the transmission spectrum being arbitrarily maskable,

Transmission power:

about -50 d8m / Hz (which in the full bandwidth is about 200 mW),

Kanaladaptivität:

bit loading 2 to 10 bits per subcarrier

spectral efficiency:

maximum 7 bit / Hz (net)

Data throughput:

maximum 205 Mbit / s (on the physical layer)

Net data throughput:

maximum approx. 120 Mbit / s (TCP)

Attenuation:

approx. 40 dB at maximum data throughput (if no interference is present and without spectrum masking) approx. 70 dB at 20% of the maximum throughput

Ie. the data transmitted by Ethernet protocol over the communication networks of the vehicle units are unpacked by a coupling device (or its modem part) and, in order to transmit them via the information bus by means of a PLC-specific protocol, are repackaged. At the receiving end, this repacking process is repeated and the user data again appear on the Ethernet interface of the coupling device. The corresponding latency is typically less than 10 ms. Furthermore, the technology used can also support special network protocols such as TCP / IP, DHCP, FTP, VLAN, http, STP, SNMP. These protocols are used, for example, for reading diagnostics data, for automatic IP address assignment, for file transfer, as access protection and for network management. In addition, the payload data typically transmitted openly via the information bus can be encrypted with a corresponding algorithm (eg 802.1 Q VLAN, DES / 3DES). The coupling devices may also have multiple interfaces (e.g., UPA powerline, 10/100 base-T, RS232).

In Fig. 6, another rail vehicle is shown. This comprises several compositions 20.1, 20.2, 20.3 each with a plurality of carriages 20.11, 20.12, 20.13, 20.14, 20.21, 20.22, 20.23, 20.24, 20.31. Each cart includes an information bus 2, which are interconnected by the information bus couplings 3 on each car to a cross-composition, ie rail vehicle-wide information bus 2. Each cart further comprises an Ethernet network 17.1, with each of the two Ethernet networks 17.1 of adjacent carriages within a composition 20.1, 20.2, 20.3 being interconnected, so that these Ethernet networks 17.1 of all carriages of a composition 20.1, 20.2, 20.3 become one common , composition-internal, ie composition-wide Ethernet 17.0 are combined. Furthermore, each composition comprises two coupling devices 5.8 operated in bridge mode, which in turn are respectively arranged at the ends of each composition and comprise a low-pass filter.

During the transmission of broadband data signals, for example from the first composition 20.1 to the second composition 20.2, these data signals are generated approximately in the server 8 of the wagon 20.11 (which in this case is a railcar of this rail vehicle) and via the Ethernet network 17.0 of this composition 20.1 transmitted to the coupling device 5.8 in the car 20.14 at the other end of this composition 20.1. The latter receives the data signal, couples it into the information bus 2, where it is transmitted via the information bus coupling 3 between the compositions 20.1 and 20.2 to the adjacent coupling device 5.8 in the carriage 20.21. This decouples the data signal from the information bus 2 and sends it via the Ethernet network 4 of this composition 20.2 to the desired location within this composition.

In this case, the low-pass filter of the coupling device 5.8 in the carriage 20.14 prevents the data signal from being transmitted via the composition-internal information bus 2 to the coupling device 5.8 in the carriage 20.11. Accordingly, the low-pass filter of the coupling device 5.8 in the carriage 20.21 prevents the data signal from being transmitted via the composition-internal information bus Z to the coupling device 5.8 in the carriage 20.14. Consequently, the broadband data signals are transmitted on the information bus 2 only via the information section sections 2.1 between two adjacent coupling devices 5.8 of two successive compositions 20.1 and 20.2 or 20.2 and 20.3.

Fig. 7 shows a schematic representation of the Ethernet network 17, by the interconnection of the individual, compositionally internal Ethernet networks 17.0 of the rail vehicle from Fig. 6 by means of operated in bridge mode coupling devices 5.8 arises.

Each cart includes at least one Ethernet switch 21, each connected to the Ethernet switch 21 of another cart of the same composition by a corresponding Ethernet cable 22. In the present example, the server 8 is connected to the Ethernet switch 21 of the car 20.11. Further, this Ethernet switch 21 of the car 20.11 is connected to the Ethernet switches 21 of the car 20.12 and 20.13, which in turn are in turn connected to the Ethemet switch 21 of the car 20.14. On the Ethernet switch 21 of this carriage 20.14 the coupling device 5.8 of this car is connected. This in turn is connected via the information bus section 2.1 between the compositions 20.1 and 20.2 with the coupling device 5.8 of the car 20:21. The ethernet switches 21 of the carriages 20.11, 20.12, 20.13 and 20.14 are thus joined together by the Ethernet cables 22 to form an annular Ethernet 17.0.

Analogously, the Ethernet switches 21 of the car 20.21, 20.22, 20.23 and 20.24 of the composition 20.2 are connected by the Ethernet cable 22 to another annular Ethernet network 17.0, wherein the two Ethernet networks 17.0 of the compositions 20.1 and 20.2 through the coupling devices 5.8 of the car 20.14 and 20.21 and the intermediate information bus section 2.1 to the rail vehicle-wide, d. H. cross-composition Ethernet network 17 are joined together.

Of course, it is also possible that per car additional Ethernet switches 21 are present, which are turned on in the composition Intemen Ethernet networks 17.0.

With the aid of corresponding, known, Ethernet-based protocols (such as the LLDP (link layer discovery protocol), it is possible to determine the structure of such an Ethernet network 17. The LLDP is described, for example, in the publication "The Discovery of the Network Topology", Markus Rentschler, Elektronik 24/2005 In turn, the order of the individual wagons of the entire rail vehicle can then be determined, for example by the server 8.

Each car usually has its own name, typically in the form of a number, which is stored in a memory of this car, for example in a switch via dongle.

In contrast, in the example shown in Fig. 8, the order of the carriages must be determined otherwise. In this example, the existing in the car 20.4, 20.5, 20.6, 20.7 coupling devices 5.8 namely operated in bus mode, so that the information bus 2 serves as a backbone for the transmission of broadband data signals between any two, anywhere connected to the information bus 2 coupling devices 5.8 , The Ethernet networks 17.1 of the individual cars, are therefore not combined to a cross-cart Ethernet network, which is why the LLDP for the order determination can not be used.

In this example, the order of the individual cars is determined by measuring the reception levels of the individual coupling devices 5.8. That Data signals, each with a specific transmission level, are transmitted via the information bus 2 and the level of the received data signal is determined at the receiving coupling device 5.8. The sequence between the two participating coupling devices 5.8 is then determined from the known transmission level and the measured reception level. From the order of coupling devices 5.8 can then determine the order of the car. The whole thing is typically done so that the signal attenuation is determined during the transmission of the data signals between a particular coupling device 5.8 and the other existing coupling devices 5.8. The particular coupling device 5.8 used for this determination of receive levels is typically that in the foremost carriage 20.4 (typically a locomotive or a railcar) and is also referred to as a master. The remaining coupling devices are then usually referred to as slaves.

In summary, it can be stated that the invention in a rail vehicle in which the individual vehicle units have an information bus designed for narrow-band data transmission, which is interconnected via corresponding information bus couplings to form a rail vehicle-wide information bus, allows to realize a transmission of data signals with a high bandwidth and in the frequency range above 1 MHz both within a vehicle unit, as well as between several vehicle units.

Claims (16)

Rail vehicle having one or more vehicle units, each comprising one or more cars, a) at least one vehicle unit comprising a unit-internal information bus designed for narrow-band data transmission, b) and the at least one vehicle unit comprises an information bus coupling at one of its ends, by means of which the unit-internal information bus of this at least one vehicle unit can be interconnected with a unit-internal information bus of another vehicle unit to form a unit-comprehensive information bus,
characterized in that c) the at least one vehicle unit comprises at least one coupling device, d) which is connected to the unit-internal information bus of the at least one vehicle unit, e) and with which broadband data signals can be decoupled from the unit-internal information bus or coupled into the unit-internal information bus and transmitted via the unit-internal information bus. Rail vehicle according to claim 1, wherein the at least one vehicle unit comprises a unit-internal communication device for transmitting data signals, in particular a communication device for a broadband data transmission, the coupling device is connected to the unit-internal communication device and the data signals with the coupling device from the unit-internal communication device off and in the unit-internal information bus can be coupled or from the unit-internal Information bus off and can be coupled into the unit-internal communication device. Rail vehicle according to one of claims 1 or 2, wherein the unit-internal information bus has at least one of the following properties: a) he is unshielded, b) it has poor symmetry for frequencies above 1 MHz, c) it includes branches, d) it has a total reflection at its ends, e) it has inhomogeneous characteristic line impedances, f) it has a high transit time dispersion. Rail vehicle according to one of claims 1-3, comprising two adjacent vehicle units, each comprising an in-unit communication device, a unit-internal information bus and at one of its ends an information bus coupling, the two unit-internal information buses are interconnected with the information bus couplings to a unitary information bus and the coupling devices in one Bridge mode are operable in which the broadband data signals between the unit-internal communication devices of the two vehicle units with a point-to-point transmission over the cross-unit information bus are transferable, wherein the coupling devices are each preferably arranged at that end of a vehicle unit with the Informationbuskupplung. Rail vehicle according to claim 4, wherein each coupling device comprises a low pass filter, which typically has a cutoff frequency of less than 1 MHz and on a side facing away from the information bus coupling side of the coupling device is connected in the unit-internal information bus, so that a propagation of the broadband data signals on the unit-internal information bus from the coupling device in the direction away from the information bus coupling can be suppressed. A rail vehicle according to any one of claims 1-3, comprising two vehicle units each comprising an in-unit information bus and an information bus coupling at one of its ends, the two in-unit information buses interconnecting with the information bus couplings to a unitary information bus, and the coupling apparatus operable in a bus mode in which the broadband data signals can be transmitted with a point-to-multipoint transmission via the cross-unit information bus. Rail vehicle according to claim 6, wherein the two vehicle units each comprise a unit-internal communication device, the coupling devices of the two vehicle units are respectively connected to the unit-internal communication device and the broadband data signals from or to a data processing device connected to a unit-internal communication device are transferable. Rail vehicle according to claim 7, wherein at least one coupling device is operable in a repeater mode in which receive the broadband data signals of a first coupling device of this at least one coupling device, regenerated and transferable to a next coupling device. Method for data transmission in a rail vehicle with one or more vehicle units, which in each case comprise one or more carriages and one unit-specific information bus designed for narrow-band data transmission,
characterized in that f) broadband data signals are transmitted via the in-unit information bus, g) by the broadband data signals coupled to a first coupling device of one of the vehicle units in the unit-internal information bus, transmitted via the unit-internal information bus and coupled to a second coupling device of one of the vehicle units from the unit-internal information bus. The method of claim 9 in a rail vehicle with two adjacent vehicle units, wherein the Einheitsintemen information buses of the two vehicle units are interconnected by means of information bus couplings of the vehicle units to a unitary information bus and the broadband data signals from a first coupling device of a first vehicle unit via the unitary information bus to a second coupling device of a second Vehicle unit to be transferred. The method of claim 10 in a rail vehicle with two adjacent vehicle units, each comprising a unit-internal communication device, wherein a) the broadband data signals between the two communication devices are transmitted by b) receiving the broadband data signals with the first coupling device from the in-unit communication device of the first vehicle unit, c) transmitted via the unitary information bus to the second coupling device and d) are supplied from the second coupling device of the unit-internal communication device of the second vehicle unit. Method according to one of claims 10-11, wherein the unit-internal communication devices of the two vehicle units are interconnected by means of the coupling devices to a cross-unit communication network by the coupling devices operated in a bridge mode and the broadband data signals between the unit-internal communication devices of the two vehicle units by means of a point to-point transmission are transmitted. A method according to any one of claims 10-12, wherein a narrowband data signal is transmitted over the information bus between the adjacent vehicle units and an information content of the narrowband data signal for the purpose of redundancy by means of the coupling devices substantially simultaneously as part of a broadband data signal over the unitary information bus between the vehicle units is transmitted. A method according to any one of claims 10-11, wherein the coupling devices are operated in a bus mode and the broadband data signals are transmitted via point-to-multipoint transmission over the inter-unit information bus. The method of claim 14, wherein at least one coupling device is operated in a repeater mode in that the broadband data signals of a first coupling device are received by this at least one coupling device, regenerated and transmitted to a next coupling device. Method according to one of claims 14-15, wherein a signal attenuation in a transmission of a data signal between the coupling devices of the vehicle units, and depending on these signal attenuations, an order of the vehicle units is determined.

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