BE1022851B1 - Verification of the operating status of a beacon - Google Patents

Abstract

The present invention relates to verifying the operating state of a beacon. A beacon measuring device is mounted on a rail vehicle which comprises a remote power supply module for the beacons to provide at least one activation signal for at least one. beacon, at least one antenna connected to the remote power supply module of the beacons and being configured to transmit at least one activation signal to at least one passive beacon and to receive signals from each passive beacon, an acquisition module connected to at least one antenna for the acquisition of the signals received by each antenna, and a processor connected to the remote power supply module for the beacons and to the acquisition module, the processor being configured to process each signal acquired to determine parameters measured with the parameters of reference to determine the operating state of each positive beacon.

Description

Verification of the operating status of a technical area tag

The present invention relates to a method for verifying the operating state of a beacon, particularly a device and a system for characterizing the beacons deployed along a railway.

Prior state of the art

In order to guarantee railway safety, a railway signaling system is deployed along the railways. Different types of signage exist, including the use of side traffic lights. However, since the advent of TGV ("High Speed Train"), a lateral signaling is no longer suitable because the latter is difficult to detect by drivers for train speeds of over 120 km / h. Current commercial TGVs can even reach speeds of 320 km / h today. Therefore, a signaling system in the cabin, including a communication between the train and the ground was deployed along the railways. This communication system allows the train driver to know his position and also allow the transmission of different information. These telecommunication systems have evolved a lot in recent years and improve rail safety but also capacity.

These telecommunication systems are national and include, for example, the following systems: the KER system which comprises the KVB system ("beacon speed control") in France, the EBICAB® system, the RSDD system (in Italian, "Ripetizione Segnali Discontinua Digitale "), the TBL1 system (" locomotive beacon transmission 1 "), etc. These systems are incompatible but have in common that they use beacons deployed along the tracks.

To overcome these problems, a European system, ERTMS (European Rail Traffic Management System) is now gradually introduced on the railways within the European Union. The ERTMS system includes the European Train Control System (ETCS) and GSM-R, the GSM mobile communication standard ("Mobile Special Group" or "Global System for Mobile Communications") for rail. The equipment of the trains on board must be adapted to this system, as well as the beacons deployed along the tracks.

Beacons are plates installed between the rails. They are installed in groups, ranging from two to eight plates to generate redundant or complementary information. These tags are passive, and require no power source. They respond to a remotely powered signal (they are inductively coupled), for example, radio frequency, broadcast by a transmission module mounted under a passing train. The transmission rate is sufficient for a complete "telegram" to be received by a train traveling at a speed of up to 500 km / h.

However, these beacons, subjected to bad weather, temperature variations, etc. degrade over time. This degradation can lead to errors in the transmission of data to trains, which is dangerous for railway safety. Tags are usually tested in labs, and their performance must meet a number of predefined criteria. When a beacon, deployed on a railway, is faulty, it is impossible today to detect it directly and to judge if a preventive or corrective maintenance action, or even a replacement of the beacon, is necessary.

The document US2012 / 0292119 A1 discloses a method for checking the strength and the presence of gluing problems of a transponder device present on board a train. This method does not measure the operating status of a beacon installed in a railway environment outside a train. SUMMARY OF THE INVENTION The invention proposes for this purpose a method for measuring the operating state of a passive beacon installed in a railway environment by using a measurement system on a railway vehicle, the method comprising: driving the vehicle rail along a predetermined path in a railway environment, transmitting at least one excitation signal from the measurement system to at least one passive beacon positioned along the predetermined path, acquiring at least one a signal from each passive beacon positioned along the predetermined path, processing each acquired signal to determine the parameters measured for each passive beacon, and comparing the measured parameters with reference parameters to determine the operating state of each passive tag.

The method according to the invention makes it easy to detect faulty or about to become tags, on a railway network. A maintenance train, a commercial train, or a TGV, passing over the beacon is able to detect faulty beacons and even to measure their operating status. It will then be very simple to determine if a maintenance action is required on the tag, or a possible replacement. All the beacons of the rail network can be measured during a measurement campaign, or simply during the passage of commercial trains. These various measures then make it possible to generate a map of the railway network indicating the operating status of each beacon.

Advantageously, the method further comprises synchronizing each transmitted excitation signal with each acquired signal.

This allows signals from the beacon to be easily determined and processed.

Preferably, the method further comprises measuring a distance between the data acquisition system placed on the railway vehicle and each passive beacon.

By measuring this distance, it is possible to account for differences in height between the measuring system and the beacon due to ground level variations, and the effect of vehicle dampers, vehicle suspension and oscillations. on the height of the vehicle. This makes it possible to obtain a more precise determination of the operating state of the beacon.

Preferably, the method further comprises compensating the disturbing components within each acquired signal. The identification and elimination of the disturbances of the acquired signal also allow a more precise determination of the operating state of the beacon. Such disturbances may be caused by objects that reflect the transmitted signal and reflections interfere with the acquired signal.

Advantageously, the method also comprises determining the location of disruptive sources that are the "large metal masses", for example bridges, allows the development of a map of these locations.

After determining the presence of disturbances, it is advantageous to match their locations so that they can easily be taken into account in subsequent paths. The invention also relates to a beacon measurement device mounted on a railway vehicle, the beacon measuring device comprising a remote power supply module for providing at least one activation signal for at least one beacon, at least one connected antenna. to the remote power supply module of the beacons and being configured to transmit at least one activation signal to at least one passive beacon and to receive signals from each passive beacon, an acquisition module connected to said at least one antenna for acquisition of the signals received by each antenna, and a processor connected to the remote power supply module of the beacons and to the acquisition module, the processor being configured to process each acquired signal to determine parameters measured for each passive beacon and to compare the measured parameters with the reference parameters to determine the operating status of each passi tag ve.

The device of the present invention can be used with current beacon systems as mentioned above which do not indicate the operating status of the beacon. The comparison of the measured parameters of the beacon with reference parameters provides an indication of the operating status of each beacon. This means that it is possible to perform validated measurements outside a laboratory.

The device also provides real-time information relating to each beacon that can either be detected by a driver of a railway vehicle on which the device is mounted or stored for processing at a later date.

Preferably, the device further comprises means for recording the excitation signals and acquired signals for each beacon.

Advantageously, the device further comprises a telemetry system for measuring the distance of a beacon from the beacon measuring device for calibrating the beacon signals.

By providing a telemetry system, it is possible to account for differences in heights between the measurement system and the beacon because of changes in ground level, etc. This makes it possible to obtain a more precise determination of the operating state of the beacon.

Preferably, the telemetry system comprises a laser telemetry system.

While any suitable telemetry system may be used, it is preferable that the laser telemetry system be used as long as it does not interfere with the signals transmitted to the beacon and the signal obtained therefrom.

Advantageously, the processor further comprises means for compensating the disturbing components within each acquired signal.

As described above, the identification and elimination of disturbances of the acquired signal also allow a more accurate determination of the operating state of the beacon. Such disturbances can be caused by objects that reflect the transmitted signal; and the reflections interfere with the acquired signal.

Preferably, the compensation means for the disturbing components comprise means for determining the location of the sources of disturbing components and means for mapping these locations.

As described above, after determining the presence of disturbances, it is advantageous to match their locations so that they can easily be taken into account in subsequent paths.

Advantageously, the device furthermore comprises a multiplexer connecting the at least one antenna to the remote power supply module of the beacons and to the acquisition module. The use of a multiplexer for signal transmission and acquisition reduces by half the number of channels needed in the device.

Preferably, the multiplexer comprises a diplexer.

If more than one channel is not needed, a diplexer can be used instead of a multiplexer. The invention also relates to a system for measuring the operating state of a passive beacon installed in a railway environment, the system comprising: a measuring device mountable on a railway vehicle and comprising: a remote power supply module for providing beacons at least one activation signal for at least one passive beacon, at least one antenna connected to the remote power supply module of the beacons and being configured to transmit at least one activation signal to at least one passive beacon and to receive signals from each passive beacon, an acquisition module connected to said at least one antenna for acquiring the signals received by each antenna, and a processor connected to the remote power supply module of the beacons and to the acquisition module, the processor being configured to process each acquired signal to determine parameters measured for each passive beacon and to compare the parameters very measured with reference parameters to determine the operating condition of each passive beacon, and at least a passive tag located in the vicinity of the beacon measuring device.

It will be appreciated that the system also has all the advantages of the device.

BRIEF DESCRIPTION OF THE FIGURES Other features and advantages of the invention will become apparent on reading the detailed description which follows for the understanding of which reference will be made to the appended figures, among which: FIG. 1 is a diagram representing the architecture of the system according to the invention, - Figure 2 is a diagram showing a first embodiment of a diplexer according to the invention, - Figure 3 is a diagram showing another embodiment of a diplexer according to the invention. FIG. 4 is a diagram showing an embodiment of the acquisition module according to the invention; FIG. 5 is a diagram representing the different steps required to carry out the method according to the invention; FIG. diagram representing the signals of the beacons; - FIG. 7 is a diagram representing the disturbances of the signal in the presence of disturbing objects.

Description of the invention

The present invention is described with particular embodiments and references to figures but the invention is not limited by them. The drawings or figures described are only schematic and are not limiting.

In the figures, identical or similar elements may bear the same references.

The present invention relates to a system (electronic and software) embedded on a train for an automatic measurement and characterization of passive inductive coupling tags used in railway signaling.

The system is based on the principle of excitation by a radio frequency remote-control signal ("Telepowering" in English) of the passive beacon followed by an acquisition of the signal emitted by it for a complete analysis. This analysis will measure all the functional parameters of the beacon in order to make a decision of a corrective or preventive maintenance action if necessary. The excitation of the passive beacons as well as the acquisition and recording of the Radio Frequency (RF) signals emitted by the latter is done in real time, preferably on board a moving train. The measurements as well as the characterization of the functional parameters of the beacon can be done in real time or in post-processing after recording.

From a functional point of view, the system generates a remote power signal with variable power, a variable carrier frequency, and with or without modulation (amplitude, frequency and phase modulation).

The variation of level makes it possible to feed the beacon with different levels of power to study the behavior of this one during remote feeding of various input stimuli. The power levels are adjustable from the minimum flow value to a maximum value that corresponds to the power level to saturate the beacon. The application or not of modulation makes it possible to excite and activate different systems of existing beacons and used in rail signaling (KER system, Eurobalise system, TBL1 + system, etc.). The modulation application can be dynamically used to work with multiple tag systems during the same measurement campaign. The modulation is an amplitude modulation (known as "AM") with the following characteristics: the modulation index is variable between 0 and 100%; and the modulating signal has pulses whose frequency is variable between 40kHz and 1MHz, the duration of the taps being variable between 0.1 ps and 25ps (in English "non-toggling AM draws width"). The duration of modulating pulses can be alternated between two values lying between 0.1 ps and 25ps (in English "toggling AM draws width").

The frequency variation of the carrier makes it possible to study the behavior of the beacon when it is excited with nominal carriers and deviating from the nominal values. The carrier frequency is between 3MHz and 30MHz.

The system detects the presence or absence of a response signal of the beacon when it is excited by the remote power supply signal. This detection is selective and can eliminate the spurious signals (residual noises, impulses, etc.) that are not useful signals. When a useful signal is detected, the high frequency acquisition of the signal is triggered (in English "trigger"). The detection is based on a technique of instantaneous power measurement of the RF signal (radio frequencies) in a determined frequency band (selective sensitivity via a bandpass filter).

The system measures and characterizes the disturbances of the remote-sensing signal at the transmitting antenna caused by the presence of metallic elements of large dimensions or very close to the transmitting antenna (large masses metal known as "Big Metallic Masses" or "BMM"), for example, bridges, metal plates under the railway, cable sheaths and guardrails on the side of the railway . The "BMM" disturb the return signal and can therefore, for reasons of rail safety, trigger an emergency stop of a train where this braking is not justified.

Pre-detection of "BMM" makes it possible to avoid emergency stops, for example by installing tags in the vicinity of "BMM", so as to inform the measuring system of the presence of "BMM". This prevents false emergency stops.

This measurement thus makes it possible to detect the presence of these disturbing elements of the remote power supply signal (presence of "BMM") in order to establish an accurate mapping along the railroad tracks of the presence thereof. The measurement of the disturbance is based on the measurement of the standing wave ratio (TOS) of the remote power supply signal.

The system records, after analog-to-digital conversion, the beacon excitation signals as well as the beacon response signals. These two acquisitions (remote power signal and beacon response signal) are completely synchronous to allow analysis and correlated measurements (in English "Output vs Input"). The analysis is based on the analog demodulation of the beacon response signals (frequency shift keying (FSK) or ASK (amplitude shift keying) demodulation).

In a preferred embodiment, the system synchronously measures the distance between the antenna on the train and the beacon on the ground via laser telemetry.

Figure 1 illustrates the different subsystems as well as the interfaces for connecting the different subsystems to each other. The beacon is shown but does not form part of the invention.

A system 100 comprises a controller module 110, a remote power supply module 120, an acquisition module 130, a diplexer module 140, an antenna 150, a laser telemetry module 160, and a beacon 170. The controller module 110 is connected to the remote power supply module 120 by two interfaces IF1 and IF2, and the acquisition module 130 by two interface IF3 and IF4. The remote power supply module 120 is connected to the diplexer module 140 by two IF5 and IF6 interface. The acquisition module 130 is connected to the diplexer module 140 via an interface IF7. The diplexer module 140 is also connected to the antenna 150 by two interfaces IF8 and IF9. The antenna 150 is connectable to the beacon 170 by two IF10 and IF11 interface when the beacon 170 is within range of the antenna 150, and the laser telemetry module 160 and also connectable to the beacon 170 by an interface IF13 when the beacon 170 is within range of the laser telemetry module 160. The laser ranging module 160 is also connected to the controller module 140 by two IF14 and IF15 interfaces. The IF12 interface connects the remote power supply module 120 to the acquisition module 130.

The controller module 110 comprises a processor configured to execute, for example, software for controlling and / or processing the signal. The processor can be part of a computer or an electronic card. Advantageously, the controller module 110 makes it possible to configure various modules including a remote power supply module 120 and an acquisition module 130 via a configuration interface IF1 and an IF3 control interface. Preferably, these interfaces are data buses of serial or parallel type (synchronous or asynchronous). They make it possible to place simple commands and to receive the statuses of the remote power supply module 120 and the acquisition module 130.

The controller module 110, via the signal measurement and processing software, preferentially measures and calculates technical parameters specific to the type of beacon under test to check whether the parameters are in the acceptable ranges according to the different predefined standards (beacon is nominal), or if they are outside this range (non-nominal beacon) then requiring corrective maintenance action.

The remote power supply module 120 is responsible for generating and amplifying a remote power supply signal, making it possible to feed and excite passive beacons 170 operating by magnetic induction coupling. The remote power supply module 120 receives, via the interface IF1, the configuration parameters generated by the controller module 110.

The power of the signal emitted by the remote power supply module 120 is variable. The frequency of the signal carrier is also variable, and may or may not be provided with amplitude modulation, frequency modulation and phase modulation. The signal power variation makes it possible to study the behavior of the beacon 170 during the power supply by different input stimuli. The power levels are adjustable from a minimum flux value to a maximum value corresponding to the power level required to saturate the beacon 170.

The remote power supply module 120 further comprises an analog-to-digital converter (in English "Analog to Digital Converter" or "ADC").

Data, generated in the remote power supply module 120, is transmitted in real time to the processor of the controller module 110 via an interface IF2. The IF2 interface is in the form of a serial or parallel data bus (synchronous or asynchronous). These data are related to the disturbance of the remote power signal. The data, sent to the controller module 110 from the remote power supply module 120, are grouped into digital data frames grouping the samples obtained at the output of the "ADC".

The acquisition module 130 is responsible for acquiring the signals transmitted by the beacons 170 in response to the remote power supply signal. The signals transmitted by the beacons are of the radio frequency (RF) type. The acquisition module 130 is composed of a circuit for filtering and selectively detecting radio frequency signals coming from the beacons via an interface IF7. The IF7 interface is preferably a radio frequency transmission line. When a beacon signal is detected, the detection circuit triggers the conversion of the beacon signal from analogue to digital. This is sampled at a rate that ranges from 10 times the carrier frequency of the beacon signal to more than 200 times the frequency of the carrier.

The acquisition module 130 is controlled and configured via the control interface IF3 (a data communication bus of serial or parallel type). The configuration parameters are, for example, the acquisition speed, the acquisition time, the number of pre-trigger samples, the type of trip). The IF3 and IF4 interfaces can be multiplexed on the same digital data transmission bus (as in the case of a USB bus).

The acquisition module 130 sends the data related to the response signal of the beacon to the control module 110 via the interface IF4. This interface is in the form of a serial data bus. The following standards can be used: "RS232" / "RS485" or "USB 2.0" / "USB 3.0". An embodiment of the acquisition module 130 is illustrated in Figure 4 and this will be described further below.

Advantageously, the generated signal is sent to the diplexer module 140 via the IF5 interface. This signal is in the form of a radio frequency (RF) signal. The IF5 interface is then an RF transmission line, for example a line on a PCB, a balanced line of the differential line type, or an unbalanced line of the coaxial type.

Two embodiments of the diplexer module 140 are illustrated in Figures 2 and 3 respectively.

Preferentially, the diplexer module 140 comprises a bidirectional RF coupler. The module also receives, via the interface IF6, the disturbances of the remote power supply signal, at the level of the antenna 150. These disturbances are generated by large metallic masses ("big metallic masses" in English or "BMM"), which disturb the electromagnetic field, and therefore disturb the antenna. The forward and reverse signals are coupled at the output of the bidirectional RF coupler. These disturbances, which correspond to a change in the standing wave ratio (TOS), are transmitted to the controller module 110, after analog-to-digital conversion. They are transmitted to the controller module 110 by the interface IF2. These data will be used to map the railways according to the presence or absence of "Big Metallic Masses", which are the main causes of changes in the Stationary Wave Rate, with the beacons themselves. This is illustrated in more detail in Figure 7.

Advantageously, the IF6 interface is an RF type interface (a transmission line). Preferably, the interface IF2 is a serial or parallel communication data BUS (serial line "UART", "SPI" or "I2C" or "USB 2.0" I "USB 3.0").

In the IF2 interface, the data is grouped into data frames containing the samples after acquisition and analog / digital conversion. The antenna 150 is responsible for transmitting the signal generated by the remote power supply module and for capturing the RF signals emitted by the beacons in order to retransmit them to the device according to the invention.

Preferably, the antenna is a "loop antenna" ("loop antenna"). In one embodiment, the antenna is dual, that is to say it comprises two separate antennas, more particularly two separate but concentric frame antennas or loops, each tuned or not to the respective operating frequencies. In another embodiment, the antenna is multiplexed, and is configured to operate with two distinct frequencies (dual frequency).

Advantageously, the system according to the invention as well as the antenna can operate in the frequency band ranging from 3 kHz to 30 MHz, thus covering the frequency bands ITU (International Telecommuncation Union) called VLF (Very Low Frequency). ), LF (in English "Low Frequency"), and HF (in English "High Frequency").

The interfaces IF10 and IF11 are radio frequency interfaces using air as a transmission medium, via a variable magnetic field as a function of time (electromagnetic wave).

In a preferred embodiment according to the invention, the device further comprises a laser telemetry module 160. This module can measure synchronously, during the acquisition of the signals emitted by the beacons, the distance between the antenna 150 which is on the train, and the beacon 170 is on the ground, via laser telemetry. The knowledge of the distance between the antenna and the beacon at the time of acquisition of the signals emitted by the beacons makes it possible to calculate and measure precisely the power of the remote power supply signals received by the beacon, as well as the level of the RF response signal. of the tag.

The signal transmitted by the beacon and measured by the receiving antenna 150 is subjected to a characteristic impedance of 50Ω. The power P of the signal received by the antenna 150 depends on the power of the signal received by the beacon 170:

where φ represents the magnetic flux through the surface of the antenna. This flow depends on the distance between the source (the beacon) and the receiving antenna (the antenna of the measuring system). By using a reference calibration (measured power for a very precisely known distance), it is then possible to correct and measure the power of the signal received by the beacon, or the magnetic flux φ, from the power P of the received signal. by the antenna, and the distance measured using laser telemetry. The IF14 interface is a control interface (serial or parallel type) for configuring laser telemetry resolution, as well as the data transmission rate. The resolution and accuracy are configurable to the millimeter by the controller module 110. The interface IF15 is the interface for transmitting the data received by the telemetry module 160 to the controller module 110. It is a data communication interface of serial or parallel type. The telemetry system performs periodic measurements of the distance by performing an analog-to-digital conversion with a sampling rate ranging from 1 Hz to 1kHz.

The laser telemetry system can however be replaced by any type of telemetry system, capable of measuring a distance in a sufficiently precise manner.

Figures 2 and 3 illustrate two different embodiments of diplexer module 140, each type of module being adapted to two different types of antennas. The first diplexer, illustrated in FIG. 2, is adapted to so-called dual antennas, that is to say having two antennas, one being dedicated to the remote power supply signal, the second to the signal emitted by the beacons. The second type of diplexer, illustrated in FIG. 3, is adapted to multiplexed antennas, that is to say having the same antenna for the two signals or an antenna with integrated diplexer.

In the case of a dual antenna, the diplexer 140 illustrated in FIG. 2 comprises a bidirectional coupler 210 making it possible to measure the coupled forward and backward signals of the remote power supply signal.

The remote power supply signal is transmitted to the diplexer module 140, and more particularly to the bidirectional coupler 210, via the IF5 interface. The bidirectional coupler 210 also receives, through the interface IF9, the return signal. In this case, the signal on IF9 is equal to or identical to the signal on IF7 that is acquired by the acquisition module 130 (in FIG. 1). These two signals are coupled in the coupler 210 and transmitted by the interface IF6 to the remote power supply module 120. The interface IF6 is represented by two distinct IF61 and IF62 interfaces so as to illustrate the forward signal, transmitted by the IF61 interface, (remote control signal, or excitation) and the return signal, transmitted by the interface IF62, respectively. However, in the implementation, these two interfaces can be multiplexed into one or separated, as illustrated in FIG.

In the case of a multiplexed antenna, the diplexer 140 illustrated in FIG. 3 furthermore comprises two selective filters, the filter 310, which is preferably high, being adapted to the frequency bands of the remote power supply signal and the filter 320 preferably passes. high, being adapted to the frequency bands of the return signal. The bidirectional coupler 210 is identical to the coupler 210 illustrated in FIG. 3. It enables the measurement, in the controller module 110, of the forward and reverse coupled signals of the remote power supply signal. The high pass filter 310 is coupled to a bidirectional RF coupler 330 which transmits signals to and receives signals from the antenna 150 through the IF8 and IF9 interfaces respectively.

FIG. 4 illustrates an embodiment of acquisition module 130 according to the invention. The acquisition module 130 preferably comprises a filtering circuit 430, preferably a bandpass, and a power detection circuit 420. The power detection circuit selects the radio frequency signals coming from the beacons via the IF7 RF interface (transmission line). . Advantageously, the acquisition module 130 also comprises a digital analog converter 410, preferably in the form of a high-speed digitizer. The high speed digitizer is connected to the detection circuit by a trigger interface 435, transmitting a trigger signal from the power detector 420 to the digitizer 410 upon detection of a beacon signal. The IF12 interface makes it possible to send a copy of the remote power supply signal to the acquisition module 130, and more particularly to the high speed digitizer 410. After the filtering circuit, the signal coming from the beacon is also directly transmitted to the high speed digitizer 410 through the 425 interface.

When a signa! beacon is detected, the detection circuit 420 triggers, by a trigger interface 435, the analog-to-digital conversion of the beacon signal in the digitizer 410. This is preferably sampled at a speed which is 10 times the frequency of the carrier the beacon signal to more than 200 times the frequency of the carrier. Similar to the IF2 interface, the interface IF4 encapsulates data from a digitizer 410 in the acquisition module 130 and transmits it to the controller module 110 (in FIG. 1). The antenna captures the analog radio-frequency (RF) signal transmitted by the beacon and transiting through the IF9 interfaces, to the diplexer 140 and then IF7, to the acquisition module 130, as illustrated in FIG. 1. Advantageously, the acquisition is carried out with a minimum vertical resolution of 12 bits and a variable acquisition speed (depending on the type of beacon) ranging from 10 mega-samples per second to 1 giga-samples per second.

In the digitizer 410, advantageously, the analog-to-digital conversion of the beacon signal is synchronous with an analog-digital conversion of the remote power supply signal supplied by the remote power supply module 120 via the radio frequency interface IF12. The start of this synchronous acquisition is determined by the rising edge of a trigger signal 435 generated by the power detector 420 which receives the signal from the beacon coming from the IF7 interface, after filtering. by the filtering circuit 430. The interface IF12 is an RF interface (radiofrequency transmission line) with an analog copy of the remote power supply signal that comes from the forward signal (IF6) of the remote power supply module.

The digital data resulting from the conversion is transmitted to the controller module 110 via the communication interface IF4 (a serial data communication bus "USB 2.0" / "USB 3.0" or parallel.) In the interface IF4, the data digitizing (analog to digital conversion) are grouped in frames with the synchronous samples of the two scanning channels (copy of the remote power signal and the beacon signal).

Returning to FIG. 1, preferably, the data of the interface IF2 are analog data which has been converted into digital data by means of an "ADC" converter located in the remote power supply module 120. This conversion can be done using a two-channel "ADC" converter with a variable vertical resolution of (10, 12, 14 or 16 bits), and a variable sampling rate of 1 to 1000 samples per second. The dual-channel ADC converter enables the synchronous acquisition of the coupled signals (return and return) recovered at the antenna output (at the beginning of the IF8 interface) by a bidirectional RF coupler (minimum coupling factor of 20 dB ). The values of the forward signal and the return signal are then used to calculate the Stationary Wave Rate (TOS) of the remote power signal. This rate may be affected by the presence of large metal objects on the track (called "BMM" as mentioned above).

FIG. 5 illustrates the different steps of the method according to the invention for detecting a faulty beacon 170. This method is preferably executed in the controller module 110.

The first step 510 of the method according to the invention comprises the step of configuring the session, and more particularly the configuration of the parameters of the remote power supply signal, the "BMM" mode, and the acquisition parameters of the signals emitted by the tags.

In the second step 515, the remote power supply configuration parameters are sent to the remote power supply module 120.

In the third step 520, the configuration parameters of the acquisition signals are sent to the acquisition module 130.

The second step 515 and the third step 520 can be performed simultaneously or in reverse order.

The fourth step 525 includes sending a command for starting the remote power signal and acquiring the signals relating to the "BMM". From the fourth step 525, two programs are executed in parallel, as illustrated in FIG.

The first concerns the acquisition of beacon signals from the generation of remote power signals. The second concerns the detection of "BMM".

The first program starts with step 530 for sending a tag signal acquisition start command. Step 535 concerns the arming of the signal acquisition trigger of the beacons. The next step 540 is a tag signal detection verification step. The program enters a loop 542, until a signal emitted by a beacon is detected. The loop stops when a signal emitted by a beacon is detected and the program proceeds to the next step 545 which consists in acquiring the signal transmitted by a beacon. Finally, in step 550, the signal transmitted by the beacon is transmitted in digital format to the control module 110. The signal is then analyzed. After transmission of the signal in step 545, the execution of this program continues for the detection of new beacon signals, triggered by step 535.

The second program starts with step 555 where the remote power signal is activated. In the following step 560, the program performs the acquisition of a round trip sample within the diplexer module 140. This step is followed by a step 565 for storing the sample in the buffer memory. This sample contains BMM information. The following step 570 is a step of checking the buffer memory, if the latter is complete. If the buffer is not complete, the program returns to step 560 to acquire a new sample and then continue. If the buffer is complete in step 570, the execution of the program continues until step 575 which consists of the transmission of the buffer memory to the control module 110. The acquisition of new samples starts over again. step 560.

Figure 6 illustrates the beacon signals that correspond to the analog RF signals emitted by the aligners after digital conversion. The trace 620 corresponds to the beacon signals, the trace 610 corresponds to the detection signals generated by the detection circuit 420 in the acquisition module 130. The two lobes 630 of the upper trace 610 correspond to ETCS beacons (Eurobalises). The third lobe 640 is a beacon type TBL1 (former system present for example in Belgium).

FIG. 7 illustrates the modulus of the reflection coefficient, calculated from the standing wave ratio (TOS) of the remote power supply signal in the diplexer module. The trace clearly shows the detection of three elements on the track. The trace 710 corresponds to an element that could be problematic from the point of view of the "BMM". It is a "crocodile" part of the "MEMOR" signaling system. The signal amplitude increases in the presence of BMM, there is a reflection of the signal. Traces 720 and 730 correspond to beacons TBL-1, and ETCS (Eurobalises) respectively. The amplitude of the signal decreases in the presence of beacons.

For beacons transmitting information with FSK-type frequency modulation, the parameters analyzed are: - the center frequency and the frequency deviation of the modulated analog signal FSK; The jitter ("jitter" in English) of amplitude of the signal FSK measured for each bit with respect to a global window which can take up 2 bits up to 1000 bits; - The precise moments when bit transitions take place. This is used to analyze also the mean data rate (MDR), but also the data transfer jitter in the form of Maximum Time Interval Error. English or MTIE). - The average transfer rate of transmitted bits, as well as the MTIE. - The demodulated signal (bits) to extract the minimum unit of information (called "telegram"). - The integrity of the telegram as well as its contents to corroborate its consistency with the information necessary to transmit to the train for the purposes of railway signaling.

In the case of beacons transmitting information with an amplitude modulation of the ASK type, the parameters analyzed are: - The precise times when the transitions of the bits take place. This is also used to analyze the mean data rate (MDR), but also the data transfer rate jitter in the form of Maximum Time Interval Error (in English). Maximal Time Interval Error "or MTIE). - The AM modulation index to ensure that it is sufficient (beyond the minimum thresholds for the correct bit detection). - The nature and frequency of the carrier of the response signal of the beacon. This includes the exact measurement of the carrier frequency, as well as the shape of the modulating signal.

The remote power supply module 120 is responsible for generating and amplifying the remote power supply signal, making it possible to power and excite the passive beacons 170 operating by magnetic induction coupling. The module receives, via the interface IF1, the configuration parameters. These include: - The carrier frequency of the remote power radio signal. This frequency depends on the type of tag used. In railway signaling, the frequency f = 27.095 MHz is recommended and harmonized and will preferably be used. The remote power supply module can, in particular, generate all frequencies from 27,000 MHz to 28,000 MHz in steps of 1 kHz; - The level (output power) of the remote power signal. This one is variable and can go from 5W (under 50Ω) to 40W (under 50Ω), measured at the exit of the interface IF8 before entering the antenna; - The type of modulation (amplitude (ASK) or frequency (FSK)) depending on the type of beacon to be powered. The signaling system based on the beacons forming part of the ETCS system uses a remote power supply signal without modulation (constant wave or "constant wave" in English, "CW"). The so-called KER beacons (KVB, Ebicab, RSDD) use an amplitude modulation (ASK) with pulses at 50kHz, the duration of which is in a time interval ranging from 2 to 3.5ps. - The parameters of the modulating signal (frequency, width of pulses and modulation index) in the case of remote power supply with amplitude modulation.

The device according to the invention is advantageously capable of operating with different types of beacons. The application or not of modulation makes it possible to excite and activate different systems of existing beacons and used in railway signaling (system KER, system

Eurobalise, TBL1 + system, etc.). The modulation application can be dynamically used to work with multiple tag systems during the same measurement campaign. The modulation is an amplitude modulation (so-called AM modulation) with the following characteristics: i) Modulation index: variable between 0 and 100%; ii) Modulating signal: pulses whose frequency is variable between 40kHz and 1MHz. The duration of the puises is variable between 0.1 ps and 25ps ("non-toggling AM draws width" in English); iii) The duration of modulating pulses can be alternated between two values ranging between 0.1 ps and 25ps ("toggling AM draws width" in English).

The frequency variation of the carrier makes it possible to study the behavior of the beacon when it is excited with nominal carriers and deviating from the nominal values. The frequency of the carrier is between 3 and 30MHz.

This section aims at presenting an example of implementation and deployment of the invention in a train. In this example illustrating the invention, the device is used to measure and characterize two types of beacons used in railway signaling in France: The ETCS beacons (Eurobalises) forming part of the new European standard for railway signaling, and so-called beacons KVB is part of an older system of signaling and transmission track-train called KER system (KVB, Ebicab, RSDD).

The device makes it possible, in this embodiment, to detect, measure and characterize the beacons of the systems mentioned above, with the aim of determining the potential deviations of thousands of beacons deployed in the field, of their nominal behavior. This problem of measuring the quality and performance of the beacons is all the more important that non-nominal beacons may not respond (transmit data to the train) and therefore are not detectable by a train with conventional reception equipment.

The modules illustrated in Figure 1 are used with the following features: - The control module 110 is divided into two parts: a low-level part with a CPU module embedded in a in a shelf of 19 inches, and a PC module with the software with measurement and processing algorithms. The remote power supply module 120 is made from a card inserted in the 19-inch shelf. This module comprises: a source of the remote power supply signal made from a digital synthesis oscillator (DDS) (controlled by the CPU module) and having a reference clock at 125 MHz. The remote power supply is generated with a variable frequency between 27MHz and 28MHz, in steps of 1 kHz. o An amplitude modulator realized using an analog multiplier with a bandwidth of 250MHz. The modulating signal is generated using a programmable logic integrated circuit (FPGA). The modulating logic signal is transposed using operational amplifiers and digital-to-analog converters (DAC) at the correct modulating levels. A power amplifier based on a power MOS RF transistor. This amplifier works in class AB. A diplexer 140 (multiplexed antenna version) comprising: o a high-pass filter (in English "HPF") cutting at 21 MHz allowing the remote power signal to pass; o A low-pass filter (in English "LPF") cutting at 11 MHz passing the beacon signal only; o A bidirectional RF power coupler with a coupling factor of 20 dB. - An acquisition module 130 high frequency 2 synchronous channels for scanning with a speed up to 400 mega-samples not seconds, with a vertical resolution of 14 bits. Beacon signals (whether they are Eurobalises or KER beacons) are RF signals with carriers around 4.2MHz. o Eurobalises (ETCS) tags send the data bits (telegram) with frequency modulation (FSK). o KVB tags (KER system) send them data bits ("telegram") with amplitude modulation (ASK). - A multiplexed antenna 150 (a single cable) with the same antenna for both frequencies. - No telemetry module.

The different features are:

The device in this embodiment generates (optionally, depending on the type of infrastructure to be measured / characterized): - A remote power supply signal in CW (in English "constant wave", no modulation), in the case of ETCS beacons (Eurobalises); - A remote power supply signal with AM non-toggling amplitude modulation for KVB beacons: this is an amplitude modulation between 50 and 100% modulation index, with pulses every 50kHz, whose duration is configurable between 2 and 4 ps;

o A remote power supply signal with AM toggling amplitude modulation for ETCS and KVB beacons (in compatibility mode): this is an amplitude modulation between 50 and 100% modulation index, with taps every 50kHz, whose duration is configurable between 2 and 4 ps, alternately for 2 values of width of taps; o A variable frequency between 27 and 28 MHz in steps of 1kHz; o Variable power between 5W and 40W of power Antenna (under 50Ω); - The device in this embodiment can perform the detection and acquisition of beacon signals: o For ETCS beacons (beacon signal with FSK modulation, data rate of 564.48 kbit / s, carrier with center frequency at 4.234 MHz) ; o For KVB beacons (beacon signal with ASK modulation, data rate 50 kbit / s, carrier with frequency at 4.2MHz); The device in this embodiment also measures the disturbances of the remote power supply signal by making the periodic acquisition (with a frequency ranging from 1 Hz to 1.44 kHz) of the coupled signals of the remote power signal sent to the antenna . These outward and return signals are used to calculate the Stationary Wave Rate and thus estimate the presence of "BMM" on the track.

A system for measuring and characterizing the operating state of inductive coupling passive tags used in railway signaling for the purpose of corrective and / or predictive maintenance. These measurements are made by synchronous acquisition of the beacon data, the energization signal (remote power supply) and optionally by measuring the antenna-beacon distance via laser telemetry.

A system for measuring and characterizing the deformation / disturbance of the remote power supply (power supply) signal of inductively coupled passive tags used in railway signaling, in order to detect the presence of large metal masses ("BMM") on the track, and thus allow a cartography of these in order to avoid alarms triggered at the computers / computers on board trains, caused by these "BMM".

A system for the acquisition and complete recording of signals of beacons deployed on the tracks in order to have a cartography of the functional state of the infrastructure beacons at the level of the lanes with a view to corrective maintenance and / or preventive.

Claims (21)

claims A method for measuring the operating state of a passive beacon (170) installed in a railway environment by using a measurement system on a railway vehicle, the method comprising: driving the railway vehicle along a predetermined path in a railway environment; transmitting at least one excitation signal from the measurement system to at least one passive beacon (170) positioned along the predetermined path; acquiring at least one signal from each passive beacon (170) positioned along the predetermined path; processing each acquired signal to determine the parameters measured for each passive beacon (170); and comparing the measured parameters with reference parameters to determine the operating status of each passive beacon (170). The method of claim 1, further comprising synchronizing each transmitted excitation signal with each acquired signal. The method of claim 1 or 2, further comprising measuring a distance between the data acquisition system placed on the railway vehicle and each passive beacon (170). The method of any of the preceding claims, further comprising compensating the disturbing components within each acquired signal. The method of claim 4, further comprising determining the location of the sources of disturbing components and mapping these locations. A beacon measuring device (170) mounted on a railway vehicle, the beacon measuring device (170) comprising: a remote power supply module (120) of the beacons (170) for providing at least one activation signal for at least one beacon (170), at least one antenna (150) connected to the remote power supply module (170) and configured to transmit at least one activation signal to at least one passive beacon (170) and to receive signals from each passive beacon (170), an acquisition module (130) connected to said at least one antenna for acquiring the signals received by each antenna, and a processor connected to the beacon remote power supply module (170) and to the acquisition module, the processor being configured to process each acquired signal to determine parameters measured for each passive beacon (170) and to compare the measured parameters with the reference parameters for determining the operating state of each passive beacon (170). 7. Device according to claim 6, further comprising means for recording the excitation signals and acquired signals for each beacon (170). The beacon measuring device (170) according to claim 6 or claim 7, further comprising a telemetry system for measuring the distance of a beacon (170) from the beacon measuring device (170) for calibrating the beacon signals (170). The beacon measuring device (170) according to claim 8, wherein the telemetry system comprises a laser telemetry system. The beacon measuring device (170) according to any one of claims 6 to 9, wherein the processor further comprises means for compensating the disturbing components within each acquired signal. The beacon measuring device (170) according to claim 10, wherein the compensation means for the disturbing components comprises means for determining the location of the sources of disturbing components and means for mapping these locations. The beacon measuring device (170) according to any one of claims 6 to 11, further comprising a multiplexer connecting the at least one antenna to the remote power supply module of the beacons (170) and to the acquisition module. The beacon measuring device (170) according to claim 12, wherein the multiplexer comprises a diplexer. 14. A system for measuring the operating status of a passive beacon (170) installed in a railway environment, the system comprising: a measuring device mountable on a railway vehicle and comprising: a remote power supply module for the beacons (170) for providing at least one activation signal for at least one passive beacon (170), at least one antenna connected to the beacon remote control module (170) and configured to transmit at least one activation signal to at least one beacon passive (170) and for receiving signals from each passive beacon (170), an acquisition module connected to said at least one antenna for acquiring the signals received by each antenna, and a processor connected to the remote power supply module beacons (170) and the acquisition module, the processor being configured to process each acquired signal to determine measured parameters for each passive beacon (170) and to compare er parameters measured with reference parameters for determining the operating status of each passive beacon (170), and at least one passive beacon (170) located in the vicinity of the beacon measuring device (170). The system of claim 14, wherein the beacon measuring device (170) further comprises means for recording the excitation signals and acquired signals for each beacon (170). The system of claim 14 or claim 15, wherein the beacon measuring device (170) further comprises a telemetry system for measuring the distance of a beacon (170) from the beacon measuring device. (170) for calibrating the beacon signals (170). The system of claim 16, wherein the telemetry system comprises a laser telemetry system. A system according to any one of suedes 14 to 17, wherein the processor further comprises means for compensating the disturbing components within each acquired signal. The system of claim 18, wherein the compensation means for the disturbing components comprises means for determining the location of the sources of disturbing components and for mapping these locations. The system according to any one of claims 14 to 19, wherein the beacon measuring device (170) further comprises a multiplexer connecting said at least one antenna to the beacon remote power module (170) and to the module acquisition. The system of claim 20, wherein the multiplexer comprises a diplexer.