EP0443438B1 - Method and device for warning persons in the track area via a high frequency communications channel - Google Patents

Abstract

The warning of persons in the track area of approaching trains by means of addressable signalling stations installed at the track which detect trains and which forward train-indicating status information via a high-frequency communications channel to an addressable warning station which is located in the working area of the persons and which is capable of transmitting an alarm is achieved despite concatenated information transmission and contact with adjacent installations by means of stations operating in time-division multiplex which identify free transmission time slots through direct reception and time slots indirectly reported by other stations as occupied.

Description

The invention relates to a method and a device for warning people in the track area with the features specified in the preamble of claims 1 and 9, respectively.

Devices are known for warning people in the track area of approaching trains by means of a high-frequency, cyclically time-multiplexed message transmission of one warning transmitter each to addressees assigned by addressing, which are carried by all workers working in the danger area (LENGEMANN, STEIN, "The individual warning system IWA" in railway engineers, 1987, H.2, p.51-56 or LENGEMANN, DOHRS, FRANK, "Automatic Rottenwarnsysteme - from the collective to the individual warning system" in Signal + Draht, 1987, H.1 / 2, p.31-38). To coordinate the multiplex method, the warning transmitter evaluates the transmission impulses of possible other warning transmitters, insofar as the transmission impulses can be evaluated on the basis of their field strength, so that the topographical area of coordination results from the field strength relationships; however, no field strength meter is used and no field strength measurement is carried out. The warning transmitters and warning receivers contain processors, the warning receivers an HF receiving part with a demodulator and antenna, and the warning transmitters furthermore an HF transmitting part with a modulator; they are not nearly identical.

Also known are devices for warning people in the track area via a high-frequency news channel through the publications ANGRABEIT, "Automation of the Rottenwarnung" in Signal + Draht, 1981, H.1 / 2, p.51-63 and LENGEMANN, "From detection to for alarming "in electric railways, 1983, H.6, p.204-209. In order to operate several such devices in the vicinity of one another, however, several high-frequency message channels are necessary in order to avoid mutual plugging of the stations. In view of the high demand for warning systems and the small number of available high-frequency channels, the described devices are practically not applicable without further measures and have not yet been used except for individual tests. Asynchronous high-frequency multiplexing methods cannot be used due to the collision resolution, which takes too long, if the transmission times overlap.

Furthermore, time-division multiplexing methods for the transmission of messages via a high-frequency channel are known (DE-AS 2818916 and DE-PS 3603907), which, however, only prevent the plugging of individual stations which send their messages to directly assigned recipients. Preventing blockages in the transmission of messages between the stations is not possible with these methods, in particular not in the case of chained, message-transmitting stations and their possibly adjacent warning systems, as is typical for systems for warning people in the track area.

The object of the invention is therefore to provide a method and a device in which it is possible to alert people in the track area in front of approaching trains by train stations set up on the track, which detect trains and signal the status information to a person located in the work area to warn capable warning station over a high-frequency message channel in time-division multiplex operation with the same transmission period, preventing clogging of the stations, even if systems of this type are adjacent.

This object is achieved according to the invention by the characterizing features of claims 1 and 9, respectively.

The method and the device according to the invention has the particular advantage that for the first time the operation of several systems for warning people in the track area against approaching trains on one single high-frequency channel is possible. In addition to a frequency economy that cannot be further improved, there is no need to plan the use of different high-frequency channels, and identical construction of warning and signaling stations is possible, which enables economical production as well as economical provision by the operator.

Advantageous developments of the invention are mentioned below.

The features of claims 2 and 10 enable the number of time slots per transmission period to be reduced by avoiding the occupancy detection of confirmed own transmission time slots of the stations.

The features of claims 3 and 11 serve a safety procedure that meets the requirements in terms of safety. Defective stations can thus be switched off and new stations can also be switched on during operation in order to increase the availability.

When warning systems are used on moving construction sites, the features of claims 4 and 12 result in an update of the time slots, so that the transmission conditions of the other stations at the previously occupied time slot can also be recorded. This is made possible by the peculiarity of the method of freely selecting a time slot from all time slots recorded and reported as not being occupied.

The features of claims 5 and 13 enable an expedient type of installation with identical construction of all reporting stations and possible savings in occupied time slots when the warning station is connected to its neighbors.

The features of claims 6 and 14 have an essential meaning. While maintaining the identical construction of the stations, they solve range problems in difficult terrain conditions, without thereby jeopardizing the security delimitation of a maximum delay time of the messages.

Claims 7 and 8 and 15 and 16 are also of significant importance. The features of claims 7 and 15 serve for the selection of the most appropriate reporting stations for their implementation or prior installation in the traveling direction of the construction site. The features of claims 8 and 16 serve for an automatic selection of the reporting stations for security monitoring.

The features of claim 17 enable known per se Measures (electrical engineering and information technology, 1988, H.11, p.491) in an economical and easily verifiable manner the safety-related disclosure of an error in the facility.

• FIG. 1 eine Anordnung der Stationen,
• FIG. 2 eine weitere Anordnung der Stationen,
• FIG. 3 die Sende-/Empfangsverhältnisse der Stationen
• FIG. 4 ein Blockschaltbild einer Station
• FIG. 5 ein weiteres Blockschaltbild einer Station

   In FIG. 1 ist die typische linienförmige Anordnung der Stationen (1 bis 9) an einer Bahnstrecke skizziert. Ein sich von links nähernder Zug wird durch eine Meldestation 1 (mit Hilfe eines den Zug und dessen Richtung erkennenden Sensors) detektiert, einer Warnstation 5 im Arbeitsbereich der Personen gemeldet und bei Passieren einer Meldestation 7 wieder abgemeldet. In umgekehrter Zugfahrtrichtung kündigt eine Meldestation 9 den Zug der Warnstation 5 an und eine Meldestation 3 meldet den aus dem Arbeitsbereich fahrenden Zug. Die für eine rechtzeitige Warnung erforderliche Entfernung der ankündigenden Stationen (1, 9) zur Warnstation (5) beträgt etwa 3 km, wohingegen die abmeldenden Stationen (3, 7) in der Nähe der Warnstation (5) aufgestellt sind. Eine Meldestation 31 einer benachbarten Warnanlage ist angedeutet. Die sich ergebenden typischen Feldstärkeverhältnisse und die sich daher im gegenseitigen Einflußbereich befindlichen Stationen sind durch die sie umschließenden Felder 21 bis 25 beispielhaft dargestellt.Exemplary embodiments of the invention are explained in more detail below with reference to the drawings. It shows

• FIG . 1 an arrangement of the stations,
• FIG . 2 a further arrangement of the stations,
• FIG . 3 the transmission / reception conditions of the stations
• FIG . 4 is a block diagram of a station
• FIG . 5 shows a further block diagram of a station

In FIG . 1 shows the typical linear arrangement of the stations (1 to 9) on a railway line. A train approaching from the left is detected by a reporting station 1 (with the aid of a sensor which detects the train and its direction), is reported to a warning station 5 in the work area of the persons and is logged off again when a reporting station 7 is passed. In the opposite direction of train travel, a reporting station 9 announces the train of the warning station 5 and a reporting station 3 reports the train leaving the work area. The distance from the announcing stations (1, 9) to the warning station (5) required for a timely warning is about 3 km, whereas the deregistering stations (3, 7) are set up near the warning station (5). A reporting station 31 of an adjacent warning system is indicated. The resulting typical field strength ratios and the stations that are therefore in the mutual sphere of influence are exemplified by the fields 21 to 25 surrounding them.

In FIG . 4 shows an example of a station (1 to 9, 31), the circuit structure of which enables the stations to be of the same type. A processor 55 connected to a clock generator 57 receives and outputs information about a transceiver 51 and its antenna 53. The communication link to the other stations is a high-frequency channel in time division multiplex operation with the same transmission period of the stations. The processor 55 is connected to a read-only memory 59 which essentially contains the program and a memory 61. He carries out work steps that can be taken directly from the claims. He can stimulate warning means 63 in a warning station (5) and detect trains and their direction by a sensor 65 in reporting stations (1, 3, 7, 9). An adjustable address 67 the processor is also fed to address the stations (1 to 9, 31). If signaling stations (3, 7) are located in the immediate vicinity of the warning station (5), they can exchange their information via lines 69 connecting them instead of via the high-frequency channel in order to reduce the otherwise required transmission time slots.

By doubling the circuit blocks 75, 77 (Fig.4) according to FIG . 5, security requirements for detecting an error can be met by the processors 55 exchanging acknowledgment signals via a connecting line in order to coordinate their approximate synchronization. If the synchronization deviations are too great, the processors 55 trigger an alarm.

In FIG . 3 shows the transmission and reception ratios in time slots (Z) 1 to 6 of a transmission period at stations 1 to 9 and 31 for the example according to FIG. 1. For each station, the own transmission time slot (S), the other stations (E) received directly due to the field strength ratios and the indirectly received time slots reported as occupied by these stations (M) are entered from bottom to top. It is initially assumed that only station 31 of the neighboring system transmits in time slot 2. It is only received directly by station 1. It is further assumed that stations 1 to 9 now go into operation in this order at intervals of a few periods. First, station 1 recognizes time slots 1 and 3 to 6 as free and, for example, selects time slot 1 as its own future transmission time slot. In the time slot 1, the station 1 also sends information about the time slot 2 recognized as occupied as a position relative to its own time slot 1, for example as a time slot increment +1, since the time slot 2 to be reported follows a time slot increment later. A simultaneous notification of the address of the station 31 received in this way is advantageous for a response to this in order to identify the report of the own time slot. In accordance with the field strength ratios 23, the message reaches stations 3 to 7 in time slot 1, which then save time slot 1 indirectly as occupied (M) for several periods due to direct reception (E) and addition of message +1 as time slot 2, the latter, in order on the one hand to counter influences of field strength fluctuations and to be able to distribute this message over several periods and on the other hand not to prevent an update. The last operating station 9 stores the time slots because of the field strength ratios 25 3 to 5 direct (E) and time slot 1 indirect (M) as busy signaling of stations 3 to 7 as occupied. The station 9 can select the free time slot 6, but also the time slot 2 already used by the station 31, as its own transmission time slot. The advantage of free selection of the time slots when recording the actual, field strength-dependent linkages of the station becomes clear: unnecessary transmission time slots are avoided, so that practically all warning systems can be operated on a high-frequency channel, even if they collide with neighboring systems. A sporadic time slot change, stimulated, for example, by a random algorithm in the processor 55, enables problem-free implementation of the stations on moving construction sites, since the station's previously occupied time slot is also checked.

The processor 55 of the signaling station 5 can stimulate the processors 55 of the signaling stations (1, 3, 7, 9) to start or stop operation or to change the operating mode, depending on a field strength measurement in the transmission, by corresponding information about the high-frequency channel. / Receiving part 51, the operation as a relay station being of particular importance in the case of poor radio propagation. Such a situation is shown in FIG . 2 shown. A reporting station (11) transmits its information to the warning station 5 via a relay station 9, in that the processor 55 of the relay station 9 buffers the received information in the memory 61 and in the next own transmission time slot plus information identifying the time between the reception time slot and the own transmission time slot sends the delay in the relay station to the warning station 5, the processor 55 of which subtracts this delay time from a stored (59) maximum permissible delay time and buffers (61) the time when it is exceeded as a result of which unsuccessful reception triggers the alarm (63) from this point in time . The implementation of the stations (1 to 11) becomes problem-free in terms of security if the processor 55 in the warning station 5 can determine its distance and direction by means of adjustable location addresses (67) by comparison with the location addresses received as information, and thus predefined in the memory 59 Minimum distance to announcing reporting stations (1, 11) can check. The processor 55 of the warning station 5 can, in an equivalent manner, check the new distance of the converted stations and automatically select the operating modes accordingly. For example, when the warning station 5 is moved to position 5a, the relay station 9 can be moved to a deregistering station can be switched due to the new conditions by warning station 5.

Claims (17)

1. Procedure for warning persons in the vicinity of the track of approaching trains, whereby addressable, train-detecting reporting stations (1, 3, 7, 9, 31) installed at the track transmit status information signaling the presence of a train to an addressable warning station (5, 5a) capable of issuing alarm signals located in the working area of the persons by means of a high-frequency communication channel in time-division multiplex mode with same transmission period,
   with the distinguishing feature
   that the stations (1 to 9, 31) directly detect time slots of other stations in their reception range (21 to 25) occupied within the transmission period,
   that the stations (1 to 9, 31) report the data concerning the position of other stations relative to their own transmission slot by means of the high-frequency communication channel, and
   that the stations (1 to 9, 31) store information on directly detected other users' time slots and received other users' time slots reported relative to same according to their relative position in the period by overwriting during several consecutive periods and that every station determines future own time slots from the information on coincidental unoccupied time slots.
2. Procedure according to Claim 1 with the distinguishing feature
   that the stations (1 to 9, 31) report the addresses of the received stations by means of the high-frequency communication channel, preferably in succession in consecutive transmission periods, and
   that the own time slot is not stored as occupied if a message containing the own address is received.
3. Procedure according to one of the preceding Claims with the distinguishing feature that the reporting stations (1, 3, 7, 9) commence operation according to selective or group enable information via the associated warning station (5) or cease operation on the basis of disable information.
4. Procedure according to one of the preceding Claims with the distinguishing feature that the reporting stations (1 to 9, 31) sporadically change the transmission time slot.
5. Procedure according to one of the preceding Claims with the distinguishing feature
   that the outside reporting stations (1, 9) announce approaching trains,
   that the reporting stations (3, 7) adjacent to the warning station (5) announce departing trains,
   that the warning station (5) triggers an alarm if approaching trains are announced or in the event of a communication link failure and cancels the alarm when the departure of trains is announced, and
   that the reporting stations (3, 7) adjacent to the warning station (5) can transmit their data to the warning station by cables (69) as an alternative to high-frequency transmission.
6. Procedure according to one of the preceding Claims with the distinguishing feature
   that, to bridge insufficient range capabilities, data from source stations (11) are transmitted via reporting stations (9) acting as relay stations to destination stations (5) by the relay stations (9) temporarily storing and subsequently sending the received message,
   that a time data with the value 0 is optionally transmitted as well by the source station (11), that the time data is incremented by the duration of the delay in message transfer in the relay stations (9), preferably by the duration of the time increments corresponding to the time slots, and that the target station (5) decrements the maximum permissible delay of the next message to be received by this value according to the received time data.
7. Procedure according to one of the preceding Claims with the distinguishing feature
   that the warning station (5) switches the reporting stations (1, 3, 7, 9, 11) to the train approach announcement, train departure announcement or relay mode as required, preferably on the basis of the field strength conditions, by way of control signals contained in the transmitted data, and that the period of grace for a communication link failure can be optionally longer for the train departure announcement than than for the train approach announcement.
8. Procedure according to one of the preceding Claims with the distinguishing feature
   that the stations (1 to 11) have an adjustable local address identifying the installation site of each station, preferably a track distance marker in 0.1 km increments, which is appended to the transmitted data,
   that the warning station (5) only accepts and enables those reporting stations (1, 9, 11) to announce approaching trains which are at a sufficient minimum distant from it to give a warning in good time, calculated on the basis of the difference between the local address of the reporting station and its own local address, and does not accept and disables from announcing trains those which are at an insufficient distance, and
   that the warning station (5) accepts and enables reporting stations (3, 7) to announce departing trains which it has identified as adjacent stations on the basis of evaluating the local addresses.
9. Device for warning persons in the vicinity of the track of approaching trains, whereby addressable, train-detecting reporting stations (1, 3, 7, 9, 31) installed at the track transmit status information signaling the presence of a train to an addressable warning station (5, 5a) located in the working area of the persons by means of a high-frequency communication channel in time-division multiplex mode with same transmission period, whereby at least one station contains a processor (55) with computer peripherals (59, 61), a transmitter/receiver unit (51), modem and an antenna (53) by means of which the messages are transmitted at a high frequency,
   with the distinguishing feature
   that all stations (1 to 9, 31) have a processor, transmitter/receiver unit including modem (51) and an antenna (53),
   that the processor (55) contained in the stations (1 to 9, 31) issues data to be transmitted to the transmitter/receiver unit (51) and obtains received data from said unit,
   that additional peripherals, optionally comprising warning devices (63) that warn persons via the processor (55) or sensors (65) that detect trains and emit signals for further processing by the processor (55), are connected to the processor (55),
   that an additional peripheral device, an address input (67), is provided for entering individual addresses and group and/or local addresses in the processor (55), and
   that the processor (55) executes the following tasks in conjunction with all its peripherals (59 to 67):
   direct detection of time slots of other stations (1 to 9, 31) in the reception range (21 to 25) of the own station occupied within the transmission period,
   reporting of the data concerning the position of other stations relative to the own transmission slot by means of the high-frequency communication channel,
   storage of information - overwriting during several consecutive periods - on directly detected other users' time slots and received other users' time slots reported relative to same according to their relative position in the period,
   determination of future own time slots from the information on coincidental unoccupied time slots.
10. Device according to Claim 9 with the distinguishing feature that the processor (55), in conjunction with all its peripherals (59 to 67), in the reporting stations (1 to 9, 31), reports the addresses of the received stations by means of the high-frequency communication channel, preferably in succession in consecutive transmission periods, and does not store the own time slot as occupied if a message containing the own address is received.
11. Device according to one of the Claims 9 or 10 with the distinguishing feature that the processor (55), in conjunction with all its peripherals (59 to 67), in the reporting stations (1, 3, 7, 9), commences operation of the station according to selective or group enable information via the associated warning station (5) or ceases operation on the basis of disable information.
12. Device according to one of the Claims 9 to 11 with the distinguishing feature that the processor (55), in conjunction with all its peripherals (59 to 67), in the reporting stations (1 to 9, 31), sporadically changes the transmission time slot.
13. Device according to one of the Claims 9 to 12 with the distinguishing feature that the processor (55), in conjunction with all its peripherals (59 to 67), in the outside reporting stations (1, 9), announces approaching trains
    that the processor (55), in conjunction with all its peripherals (59 to 67), in the reporting stations (3, 7) adjacent to the warning station (5), announces departing trains,
    that the processor (55), in conjunction with all its peripherals (59 to 67), in the warning station (5), triggers an alarm if approaching trains are announced or in the event of a communication link failure, and cancels the alarm when the departure of trains is announced, and
    that the processor (55), in conjunction with all its peripherals (59 to 67), in the reporting stations (3, 7) adjacent to the warning station (5), can transmit data to the warning station (5) by cables (69) as an alternative to high-frequency transmission.
14. Device according to one of the Claims 9 to 13 with the distinguishing feature that the processor (55), in conjunction with all its peripherals (59 to 67), in reporting stations (9) acting as relay stations, transmits data from source stations (11) to destination stations (5) to bridge insufficient range capabilities by way of the computer temporarily storing and subsequently sending the received message, optionally transmits a time data with the value 0 from the source station (11) as well and increments the time data by the duration of the delay in message transfer in the relay stations (9), preferably by the duration of the time increments corresponding to the time slots,
    and that the processor (55), in conjunction with all its peripherals (59 to 67), in the target station (5), decrements the maximum permissible delay of the next message to be received by this value according to the received time data.
15. Device according to one of the Claims 9 to 14 with the distinguishing feature that the stations (1 to 9, 13) have a field strength meter in the transmitter/receiver unit (51), and
    that the processor (55), in conjunction with all its peripherals (59 to 67), in the warning station (5), switches the reporting stations (1, 3, 7, 9, 11) to the train approach announcement, train departure announcement or relay mode as required, preferably on the basis of the field strength conditions, by way of control signals contained in the transmitted data, and determines a period of grace for a communication link failure that is optionally longer for the train departure announcement than for the train approach announcement.
16. Device according to one of the Claims 9 to 15 with the distinguishing feature that the processor (55), in conjunction with all its peripherals (59 to 67), in the stations (1 to 11), can read in an adjustable local address identifying the installation site of each station, preferably a track distance marker in 0.1 km increments, which the processor appends to the transmitted data,
    that the processor (55), in conjunction with all its peripherals (59 to 67), in the warning station (5), only accepts and enables those reporting stations (1, 9, 11) to announce approaching trains which are at a sufficient minimum distant from the warning station to give a warning in good time, calculated on the basis of the difference between the local address of the reporting station and its own local address, and does not accept and disables those from announcing trains which are at an insufficient distance, and
    that the processor (55), in conjunction with all its peripherals (59 to 67), in the warning station (5), accepts and enables reporting stations (3, 7) to announce departing trains which it has identified as adjacent stations on the basis of evaluating the local addresses.
17. Device according to one of the Claims 9 to 16 with the distinguishing feature that the stations (1 to 11, 13) contain two circuit blocks (75, 77) each with the internal devices (55 to 69), that the circuit blocks (75, 77) are connected to the transmitter/receiver unit (51) by way of a cable, and that they coordinate an approximate synchronism of their processors (55) by means of acknowledgment signals via cables (71) that link the blocks and, in the event of excessive losses of synchronism, trigger an alarm by way of the high-frequency stage (51) and the warning devices (63).

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