Method, rail vehicle and balise for a railway track system

Abstract

The invention relates, among other things, to a balise (30) for mounting in or next to the track bed of a railway track system (1) and for transmitting balise signals to passing rail vehicles. According to the invention, the balise comprises at least two antennas (35a, 35b), each of which is suitable for generating an electromagnetic field, wherein the antennas (35a, 35b) can be individually controlled by a control unit (40) of the balise, and wherein the control unit (40) is designed such that it continuously switches between at least two control modes during its operation, which differ in the control of the antennas (35a, 35b).

Description

[0001] The invention relates to rail vehicles and railway track systems equipped with balises.

[0002] It is common practice to equip railway balises with an antenna to transmit balise signals to passing trains. Eurobalises, for example, are currently in use.

[0003] The balise signals or magnetic fields generated by the balises are known to couple into neighboring conductive structures, so that interfering magnetic fields and interference signals can occur, which are received by passing rail vehicles and may lead to errors (incorrect location, etc.) in signal evaluation.

[0004] The invention is based on the objective of providing an improved balise with respect to the described coupling problem.

[0005] This problem is solved according to the invention by a balise with the features according to claim 1. Advantageous embodiments of the balise according to the invention are specified in the dependent claims.

[0006] According to the invention, the balise comprises at least two antennas, each of which is suitable for generating an electromagnetic field, wherein the antennas can be individually controlled by a control unit of the balise, and wherein the control unit is designed such that it continuously switches between at least two control modes during its operation, which differ in the control of the antennas.

[0007] A significant advantage of the balise according to the invention is that, due to the at least two control modes provided, a rail vehicle can distinguish, based on received signal level profiles, better than with known balises without different control modes, whether it has actually passed over a balise whose signals, in particular data telegrams, are to be used, or whether it has instead passed over a passive interference coupling element whose signals or data telegrams should not be used.

[0008] It is considered advantageous if, in the case of simultaneous active antenna operation, the fields of the antennas form a common superposition field and the control device, in a first control mode, generates a first signal level profile of the superposition field over the longitudinal direction of the track bed and, in a second control mode, a second signal level profile of the superposition field over the longitudinal direction of the track bed, wherein the first signal level profile differs from the second signal level profile.

[0009] In the latter configuration, it is advantageous if the control device, in transmit mode, supplies the first antenna with a first transmit signal and the second antenna with a second transmit signal, whereby the first and second transmit signals are identical, but have a first phase relationship to each other in the first control mode and a second phase relationship to each other that differs from the first in the second control mode.

[0010] The first and second antennas are preferably operated in synchronous mode in the first drive mode and preferably in push-pull mode in the second drive mode, so that the first phase is zero and the second phase is 180 degrees.

[0011] In another embodiment, considered advantageous, the control unit supplies the first antenna with a transmit signal and leaves the second antenna inactive in the first control mode, and in the second control mode supplies the second antenna with a transmit signal and leaves the first antenna inactive. The latter embodiment is particularly advantageous when the antennas have different transmit characteristics, for example, when one antenna is horizontally oriented and the other vertically oriented.

[0012] With regard to the vehicle-side evaluation of the received signal levels, it is advantageous if the control unit periodically switches between at least two control modes.

[0013] It is particularly advantageous if the control unit operates each of the control modes for a predetermined period of time and changes the control mode when the respective period of time has elapsed.

[0014] The specified time period is preferably between 50 and 1000 microseconds.

[0015] It can also be advantageously provided that the control device is designed to calculate the time span itself, depending on a predetermined maximum speed of the rail vehicles traveling on the railway track and a predetermined minimum number of control mode changes per crossing event, for example according to T = L / N * V where T is the time interval, N is a desired, predetermined minimum number of control mode changes during a passage at a predetermined maximum speed, V is the predetermined maximum speed, and L is a contact length. The contact length indicates the distance traveled – viewed in the track bed or rail longitudinal direction – over which signal or data reception with a predetermined minimum signal strength can realistically be considered during a passage.

[0016] At least one of the antennas is preferably a loop antenna comprising at least one conductor loop.

[0017] The loop plane of the conductor loops is preferably aligned at an angle, in particular at right angles, or parallel to the track bed plane after the balise has been properly mounted.

[0018] The antennas are arranged along a predetermined mounting direction, which, after proper installation in the track bed, corresponds to the longitudinal direction of the track bed, preferably with a distance between them.

[0019] It is advantageous if at least two antennas, especially their loop planes, are arranged horizontally after proper installation.

[0020] Alternatively or additionally, it may be advantageously provided that at least two antennas, in particular their loop planes, are arranged vertically after proper installation.

[0021] Alternatively or additionally, it can be advantageously provided that, after proper assembly, at least one antenna, in particular its loop plane, is arranged horizontally and at least one other antenna, in particular its loop plane, is arranged vertically.

[0022] The invention also relates to a rail vehicle. With regard to the rail vehicle, the invention provides that it has a plausibility check device configured to check, upon receiving a signal, whether its received level profile exhibits a typical profile for the presence of control mode changes of a balise, which is designed, for example, as described above, and to reject the received signal if this is not the case.

[0023] Regarding the advantages of the rail vehicle according to the invention, reference is made to the above statements in connection with the balise according to the invention and its advantageous embodiments.

[0024] The invention also relates to a method for operating a balise, for example one as described above. According to the invention, the method comprises at least two antennas, each capable of generating an electromagnetic field, and the operation of the balise continuously switches between at least two control modes that differ in the way the antennas are controlled.

[0025] Regarding the advantages of the method according to the invention and its advantageous embodiments, reference is made to the above statements in connection with the balise according to the invention and its advantageous embodiments.

[0026] The invention also relates to a railway track system with at least one balise arranged in or next to a track bed, as described above.

[0027] The invention is explained in more detail below with reference to exemplary embodiments; the following are shown as examples: Fig. 1 shows a railway track system equipped with a balise with a horizontally oriented loop antenna and additionally with a passive, loop-shaped coupling element lying in the track bed and a passive linear coupling element also lying in the track bed. Fig. 2 shows the course of magnetic field lines of a system connected to the balise according to... Figure 1 generated magnetic field and the coupling of this magnetic field into an external, horizontal coupling loop, Fig. 3 a first embodiment for a balise according to the invention, Fig. 4 a receivable signal level profile during a crossing over the balise according to Figure 3for common-mode and differential-mode operation, Fig. 5 shows a receivable signal level profile during a crossing over the passive loop-shaped coupling element according to Figure 1 In the case of external coupling, specifically in the case of common-mode and differential-mode operation of active interference coupling, Fig. 6 shows a receivable signal level profile when passing over the passive linear coupling element according to Figure 1 In the case of external coupling, specifically in the case of common-mode and differential-mode operation of active interference coupling, Fig. 7 shows an embodiment of a rail vehicle according to the invention when crossing the balise. Figure 3 , Fig. 8 shows an exemplary signal level profile that the rail vehicle according to Figure 7 during a crossing over the balise according to Figure 3would measure, specifically in the case of fifty operating mode changes of the balise during the crossing, Fig. 9 shows an exemplary signal level profile that the rail vehicle would measure according to Figure 7 during a crossing over the passive loop-shaped coupling element according to Figure 1 would measure, specifically in the case of fifty operating mode changes of the active interference coupling, Fig. 10 shows an exemplary signal level profile that the rail vehicle would measure according to Figure 7 during a crossing over the passive linear coupling element according to Figure 1 would measure, namely in the case of fifty operating mode changes of the active interference coupling, and Fig. 11 further embodiments for balises according to the invention. For the sake of clarity, the same reference symbols are always used in the figures for identical or comparable components.

[0028] The Figure 1Figure 1 shows a section of a railway track system 1 equipped with a balise 5. The balise 5 includes a loop antenna 10, the loop plane SE of which is aligned parallel to the track bed plane GBE, i.e., horizontally. The track bed plane GBE is spanned in the area of ​​the balise 5 by rails 20 of the railway track system 1.

[0029] The one in Figure 1The section of railway track 1 shown is traversed by a rail vehicle, of which, for clarity, only two bogies, each with two axles 15, are depicted. It can be seen that the axles 15 and the rails 20 electrically form an external coupling loop 25, which encloses the loop antenna 10 of the balise 5. Thus, the field lines of the magnetic field generated by the loop antenna 10 penetrate the coupling loop 25 and induce an inductively coupled coupling current Ik within the coupling loop 25. This coupling current Ik, in turn, generates a magnetic field, namely an interference field that disrupts data transmission between the rail vehicle and the balise 5.

[0030] The Figure 1The figure also shows a passive, loop-shaped coupling element 26 lying in the track bed and a passive, linear coupling element 27 lying in the track bed in the form of a cable 27, which also generate their own interference fields when external electromagnetic fields are coupled in.

[0031] The Figure 2 shows the course of the magnetic field lines of the desired magnetic field generated by the loop antenna 10 and the coupling of this magnetic field into the external coupling loop 25 in a simplified representation.

[0032] The Figure 3Figure 1 shows a first embodiment of a balise 30 according to the invention. The balise 30 comprises a first antenna in the form of a first loop antenna 35a and a second antenna in the form of a second loop antenna 35b, each equipped with at least one conductor loop and each suitable for transmitting balise signals to passing rail vehicles. The loop antennas 35a and 35b are offset or arranged one behind the other in the direction of travel or track longitudinal direction X, and their loop planes SE are each aligned horizontally or parallel to the track bed plane GBE. The loop antennas 35a and 35b of the balise 30 can each have a plurality of conductor loops and, for example, each be formed by a coil. In the latter case, the coil longitudinal axes in the embodiment according to Figure 1 are Figure 3 preferably arranged perpendicular to the track bed plane GBE.

[0033] The distance between the loop antennas 35a and 35b – viewed in the direction of travel X – is preferably between 5 cm and 15 cm. The loop antennas 35a and 35b preferably have the same cross-sectional area.

[0034] A control unit 40 of the balise 30 is preferably designed such that, in transmit mode, it supplies the loop antennas 35a and 35b each with an antenna-specific transmit signal in the form of an antenna-specific alternating current. The transmit signal or the antenna current for the first loop antenna 35a is in the Figure 3 with the reference symbol I1 and the transmit signal or the antenna current for the second loop antenna 35b is in the Figure 3 marked with the reference symbol I2.

[0035] The antenna currents I1 and I2 are preferably alternating currents, which may additionally be encoded or modulated to transmit data such as data telegrams. Generally known methods, such as those used for the Eurobalise, can be employed for generating the antenna currents and for their encoding or modulation. The Eurobalise is described, for example, in the publication "Application of the Eurobalise at DB Netz AG" (Signal+Draht Special, October 2015).

[0036] The fields of the loop antennas 35 overlap, so that in the case of simultaneous active antenna operation they form a common superposition field.

[0037] The control unit 40 can, for example, be operated by means of appropriate hardware and / or software programming either in a first control mode (operating mode), which produces a first signal level profile of the superposition field over the longitudinal direction of the track bed or the direction of travel X, or in a second control mode (operating mode), which produces a second signal level profile of the superposition field over the longitudinal direction of the track bed or the direction of travel X; the first signal level profile differs from the second signal level profile.

[0038] In the first control mode, the loop antennas 35 are operated, for example, with transmitting signals or antenna currents that have a first phase relationship to each other, and in the second control mode with transmitting signals or antenna currents that have a second phase relationship that differs from the first.

[0039] In the first control mode, it is preferably the case that the first antenna current I1 and the second antenna current I2 are equal in magnitude and in phase, i.e. the loop antennas 35 are operated in common mode and the following applies: I 1 = I 2 .

[0040] In the second control mode, it is preferably the case that the first antenna current I1 and the second antenna current I2 are equal in magnitude and in opposite phase, i.e. the loop antennas 35 are operated in push-pull mode and the following applies: I 1 = − I 2 .

[0041] The Figure 4The figure shows – for any height above balise 30 – the signal level of the superimposed field over the direction of travel or longitudinal direction X of the track bed, using the Hz component as an example. The figure on the left shows the first control mode, in which the loop antennas 35 are operated in common phase, and the figure on the right shows the second control mode, in which the loop antennas 35 are operated in opposite phase. It can be observed that the magnetic field distribution differs significantly between common-phase and opposite-phase operation. In the event of a train passing over the balise, the respective control mode can therefore be identified based on the received signal level profile, as will be explained in more detail below.

[0042] The first and second control modes are preferably set alternately, each for a predetermined time interval T. It is advantageous if the balise 30 switches periodically between the two control modes. The switching frequency f should be selected such that a sufficient number of mode changes are generated during each balise pass, enabling control mode recognition and thus balise recognition by pattern evaluation; for this purpose, the minimum number N of mode changes per pass should preferably be at least ten. In the embodiments shown below, the number of mode changes N is, for example, 50 per pass for the illustrated balise pass.

[0043] The magnetic field of the balise 30 can typically be detected in a range (viewed in the X direction) of L ≈ 1 to 1.5 m. This length L can be described as the contact length between the rail vehicle and the balise. Therefore, the lower limit of the switching frequency f depends on the maximum permissible speed V of the rail vehicle, so that mode changes are detectable even with fast rail vehicles and short crossing times. At the same time, the switching frequency f should be significantly lower than the center frequency fc of the balise telegram used for data transmission to avoid interference or disruption of the data transmission; this center frequency fc is typically 4.2 MHz, so preferably: fc ≫ f > 1 / T = N * V / L where T denotes the time span of each control mode, N the predetermined minimum number of control mode changes per crossing event, and V the predetermined maximum speed. The minimum number N of control or operating mode changes is preferably greater than 10.

[0044] For a maximum speed V of 250 km / h of a rail vehicle, a switching frequency f in the range between 1 and 20 kHz is therefore plausible, so that a suitable time range for each control mode (i.e., common-mode or differential-mode operation) in the range between 50 μs < T = 1 / f < 1 ms may lie.

[0045] In the Figure 4The switching of the control modes is also shown, specifically for N=50 mode changes per crossing; circles indicate phases in which the respective control mode is active and dashed lines indicate phases in which the respective control mode is inactive; accordingly, active phases marked by circles in the left diagram correspond to inactive phases marked by a line in the right diagram, and vice versa.

[0046] The Figure 5 (left for the first control mode and right for the second control mode) shows, for comparison, the signal level curve for the field that controls the first coupling element 26 according to Figure 1 in the event of coupling.

[0047] The Figure 6 (left for the first control mode and right for the second control mode) shows, for comparison, the corresponding signal level curve for the field that controls the second coupling element 27 according to Figure 1 in the event of coupling.

[0048] The Figure 7 shows a rail vehicle 80 crossing over balise 10 according to Figure 3 The rail vehicle 80 includes a receiving antenna 85 with which it can measure the signal level profile of the superposition field during the crossing or sample it by forming sample values.

[0049] The Figure 8 This shows an example of a signal level profile received by rail vehicle 80 during its passage. The received signal level profile is clearly described by combining the values ​​shown in the circles. Figure 4 marked level curve sections of the respective signal level curves of the two control modes, which are alternately active or inactive over time.

[0050] The Figure 9 For comparison, the corresponding signal level profile received by the rail vehicle 80, which the first coupling element 26 according to Figure 1 would be generated in the case of overcoupling. Figure 10 For comparison, the corresponding signal level profile received by the rail vehicle 80, which the second coupling element 27 according to Figure 1 would be generated in the case of overcoupling.

[0051] The rail vehicle 80 can now evaluate the received signal level profile, for example by numerically evaluating the temporal progression of the sampled values ​​of the received signal level profile, and determine, for example by means of a pattern comparison, whether the expected signal level profile for balise 30 or a different signal level profile, such as one of the ones in the Figures 8 and 9 The displayed routes were received. In the event of a detected balise crossing, the received balise telegrams are evaluated; otherwise, they are discarded.

[0052] Furthermore, in the event of detected interference coupling, the rail vehicle 80 can infer the design of the coupling element from the signal level profile; this data can be used at a later time on the trackside to identify interfering elements and, if necessary, remove them or shield them constructively.

[0053] To facilitate the described evaluation of the signal level profiles, the rail vehicle 80 includes a plausibility testing device 86, which is designed to check, upon receipt of a received signal, whether its signal level profile exhibits a profile typical for the presence of operating mode changes in balises or not.

[0054] The plausibility check device 86 can, for example, be integrated as a software module in a vehicle control unit 90, which is connected to the vehicle-side receiving antenna 85.

[0055] The vehicle control unit 90 is used in the embodiment according to Figure 7formed by a computer system 100, which comprises a computing unit 110 and a memory 120. Software is stored in the memory 120, which has at least two control modules. One of these control modules is a standard communication module 140, which, when implemented by the computing unit 110, enables standard data telegram reception of balise-side data telegrams, as is generally known in rail vehicles. Another of these control modules is a plausibility check module 150, which, when implemented by the computing unit 110, evaluates samples of signal level profiles by comparing the profile of the samples, for example, with stored typical reference profiles for balise crossings; the typical reference profiles can be stored measurement data or simulated data. If the respective measured profiles of the samples correspond to the profiles expected for balises, as exemplified by the Figures 8 to 10 As has been explained, the plausibility check module 150 concludes that a balise crossing took place.

[0056] In the event of a detected balise crossing, the plausibility check module 150 transmits this test result PE to the communication module 140, which then in turn performs an evaluation of the corresponding data telegrams or, if such an evaluation has already taken place, releases the final use of the data telegrams.

[0057] If no positive test result PE of the plausibility check module 150 is available or if the plausibility check module 150 could not confirm a balise crossing, then preferably no data telegram evaluation takes place or data telegrams already available are discarded.

[0058] Memory 120 can contain additional software in the form of further software modules that can take over further control, regulation or monitoring functions of the rail vehicle.

[0059] The concept described above, using two horizontally arranged loop antennas as an example, of employing at least two alternating drive modes, can also be implemented in a similar manner with other arrangements of two or more antennas (e.g., loop antennas). Figure 11 Figure 30 shows an example of a balise 30 with two vertically arranged antennas 200 (e.g., loop antennas) and a balise 30 with one vertically arranged antenna 200 (e.g., loop antenna) and one horizontally arranged antenna 300 (e.g., loop antenna). Naturally, the number of balise antennas and the number of different control modes can be greater than two. Furthermore, the antenna arrangement is not limited to a vertical or horizontal configuration; other arrangements, such as angled configurations with different angles relative to the track bed, are also conceivable.

[0060] The antenna concept described above is particularly suitable for "non-ETCS applications", especially in the area of ​​local public transport.

[0061] Finally, it should be mentioned that the features of all the embodiments described above can be combined with each other in any way to form further embodiments of the invention.

[0062] Furthermore, all features of dependent claims can each be combined with each of the subordinate claims, either individually or in any combination with one or more other dependent claims, to obtain further embodiments. Reference symbol list

[0063] 1 Railway track system 5 Balise 10 Loop antenna 15 Axle 20 Rails 25 External coupling loop 26 Passive coupling element 27 Passive coupling element 30 Balise 35a Loop antenna 35b Loop antenna 40 Control unit 80 Rail vehicle 85 Receiving antenna 86 Plausibility check device 90 Vehicle control unit 100 Computer system 110 Computing unit 120 Memory 140 Communication module 150 Plausibility check module 200 Antenna 300 Antenna GBE Track bed level I1 Antenna current I2 Antenna current Ik Coupling current PEP Test result SE Loop level X Direction of travel / Track longitudinal direction

Claims

1. Balise (30) for mounting in or beside a track bed of a railway track system (1) and for sending balise signals to passing railway vehicles, d a characterized by , that - the balise comprises at least two antennas (35a, 35b) each suitable for generating an electromagnetic field, - wherein the antennas (35a, 35b) can be individually controlled by a control device (40) of the balise, and - wherein the control device (40) is designed such that it continuously switches between at least two control modes during its operation, which differ in the control of the antennas (35a, 35b).

2. Balise (30) according to claim 1, d a characterized by, that - fields of the antennas (35a, 35b) form a common superposition field in the case of simultaneous active antenna operation and - the control device (40) in a first control mode generates a first signal level profile of the superposition field over the longitudinal direction (X) of the track bed and in a second control mode generates a second signal level profile of the superposition field over the longitudinal direction (X) of the track bed, wherein the first signal level profile differs from the second signal level profile.

3. Balise (30) according to claim 2, d a characterized by, that - the control device (40) in transmit mode supplies the first antenna (35a) with a first transmit signal (I1) and the second antenna (35b) with a second transmit signal (I2), - wherein the first and second transmit signals (I1, I2) are identical, but in the first control mode have a first phase relationship to each other and in the second control mode have a second phase relationship to each other that differs from the first.

4. Balise (30) according to claim 3, d a characterized by , that the first and second antennas (35a, 35b) are operated in the first drive mode in clock mode and in the second drive mode in push-pull mode, i.e. the first phase position is zero and the second phase position is 180 degrees.

5. Balise (30) according to claim 1, characterized by the fact thatIn the first control mode, the control unit (40) supplies the first antenna (35a) with a transmit signal (I1) and leaves the second antenna (35b) inactive, and in the second control mode, it supplies the second antenna (35b) with a transmit signal (I2) and leaves the first antenna (35a) inactive.

6. Balise (30) according to any one of the preceding claims, characterized by the fact that the control unit (40) periodically switches between at least two control modes.

7. Balise (30) according to any one of the preceding claims, characterized by the fact that the control device (40) operates each of the control modes for a predetermined time period (T) and changes the control mode when the respective time period has elapsed.

8. Balise (30) according to claim 7, characterized by the fact that The specified time interval (T) is between 50 and 1000 microseconds.

9. Balise (30) according to any one of the preceding claims 7 to 8, characterized by the fact thatthe control device (40) is designed to calculate the time interval (T) itself as a function of a given maximum speed (V) of rail vehicles (80) traveling on the railway track and a given minimum number of control mode changes per crossing event, according to T = L / N * V where T denotes the time span, N the specified minimum number of control mode changes, V the specified maximum speed, and L a contact length that enables data transmission between the rail vehicle and the balise.

10. Balise (30) according to any one of the preceding claims, characterized by the fact that at least one of the antennas (35a, 35b) is a loop antenna comprising at least one conductor loop.

11. Balise (30) Claim 10, characterized by the fact thatthe loop plane (SE) of the conductor loops is aligned at an angle, in particular at right angles, to the track bed plane (GBE) or parallel to the track bed plane (GBE) after the balise (30) has been installed as intended.

12. Balise (30) according to any one of the preceding claims, characterized by the fact that the antennas (35a, 35b) are arranged at a distance from each other along a predetermined mounting direction, which, after proper installation in the track bed, corresponds to the longitudinal direction (X) of the track bed.

13. Rail vehicle (80), characterized by the fact that this includes a plausibility check device (86) which is configured to check, upon receipt of a received signal, whether its received level profile exhibits a typical profile for the presence of control mode changes in balises designed according to one of the preceding claims and to reject the received signal if this is not the case.

14. Method for operating a balise (30), for example one according to any of the preceding claims, characterized by the fact that - the balise (30) comprises at least two antennas (35a, 35b) each suitable for generating an electromagnetic field, - wherein during operation of the balise (30) there is continuous switching between at least two control modes which differ in the control of the antennas (35a, 35b).

15. Railway track system (1) with at least one balise (30) arranged in or next to a track bed, characterized by the fact that the balise (30) is a balise according to any one of the preceding claims 1 to 12.

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