JPH088805A - Train line system of electromagnetic communication link use - Google Patents

Abstract

PURPOSE: To provide a communication link including a radio link through a free space between vehicles. CONSTITUTION: A multiplexer 17' multiply transmits a signal expressing the various system states of a vehicle, and processes it into a first digital train line signal on at least a first vehicle 5 of the vehicles of a train. A transmitter 19' converts the digital train line into an RF signal, and transmits it from the first vehicle 5 through a free space to a second vehicle 3 by an antenna. The second vehicle 3 receives the RF signal by an antenna, demodulates the signal, and converts it into a second digital signal train line. A demultiplexer multiply separates the second digital train line signal into a proper format which is freely readable by a train system on the second vehicle 3. The first and second vehicles 3 and 5 include the multiplexes 17' and 17", demultiplexer, transmitters 19' and 19", and receiver, and mutual communication can be attained between the first vehicle 5 and the second vehicle 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a new communication link that allows communication between vehicles of a multi-vehicle transportation means such as a railroad train or a subway train, and more particularly, a free communication between adjacent vehicles of a railroad train or a subway train. The present invention relates to communication links including spatial wireless communication.

[0002]

2. Description of the Related Art Railway vehicles are often connected or disconnected when the system is changed according to the needs such as the number of passengers or the amount of cargo, daily work, maintenance, use of operating vehicles or trains. In this sense, train organization and reorganization are important regardless of train operation, that is, whether or not to consider time per vehicle, man-hours, downtime, and the like. Therefore, such a process should be as simple and automated as possible. It is true that trains consist of different types of vehicles and in some cases rarely disconnect a particular group of vehicles, but it is also true that many connections and disconnections are made daily each day. . An example of the current system is 199
Demarais US Pat. No. 5,121,410, Jul. 9, 2
No. As shown in FIGS. 4 and 5 of this patent, the communication line between vehicles n-1, n, and n + 1 is accomplished by twisting a pair of wires. The present invention focuses on the problem of how to properly communicate information between cars without blocking the connection or disconnection of train cars.

The invention proposes a solution for transmitting large amounts of reliable information between vehicles. The communication of information in the form of electrical signals between devices installed in different vehicles has been a common feature for many years. The transmission of these signals through the electric path is called a "train line".
Train lines consist of bundles of wires, each bundle connected to an electrically continuous path over the length of the train. Devices on the vehicle that use the train line can interact with each other in a variety of ways. For example, one vehicle's device, such as a switch, can be used to control a number of similar devices on each car in the train, such as lights. Also, a specific type of sensor can be installed in each vehicle. When a certain condition occurs in a vehicle, it may be necessary to activate a warning buzzer installed in the driver's cab of the leading vehicle by this sensor. With the development of electronic technology in the past two years, changes in the method of transmitting train line information have caused new problems for train line designers. The text deals with two interrelated factors: information content and information reliability.

In general, the amount of information transmitted between rail vehicles has increased over the last two years. It is expected that the amount of information will continue to increase until a certain period as electric equipment and electronic devices are used in the train system of each vehicle. This increased information flow can be handled in two ways.
That is, there is a method of processing the increased information flow by increasing the number of wires, or a method of causing each wire to process a large amount of information. Reliable communication of information between vehicles is essential for current or always safe and efficient train operation. In each vehicle, reliability can be obtained with mechanical connectors that are mechanically safe and rarely opened. However, during communication between adjacent vehicles, the connecting elements of adjacent vehicles must be automatically and frequently connected and disconnected, which renders the conventional electrical connector ineffective. The use of such connecting elements causes many problems and interferes with metro inspection. Some of these problems are listed below. 1. Poor electrical connection caused by pin oxidation. 2. Poor electrical connection caused by dirt, oil, or foreign matter that accumulates when the pin is removed and exposed. 3. Prevents electrical connection when the pin fails to return from its proper position due to dirt, oil, or foreign matter accumulated inside the pin tube. 4. The current flowing through the spring is unusually large compared to the electrical shunt,
Prevents electrical connection when the spring fails to return due to the loss of spring elasticity that occurs sequentially due to the deterioration of spring steel.

The above-mentioned problem is that it hinders inspections and that maintenance is expensive. Pins should be checked and cleaned regularly to ensure correct operation. The prior art uses optical devices,
Linked communication between cars in Cebuset and between a subset of trains disclosed in U.S. Pat. No. 4,682,144 of Ochiai et al., July 21, 1987. In optical systems in the environment of subway trains or railroad trains, the problem is that the optocouplers get soiled in a very short time because the system is operating in a very dirty environment. The dirt that accumulates on the photocoupler degrades the optical transmission and renders it completely useless. Accordingly, US Pat. No. 4,682,
The optical system disclosed in No. 144 is not a practical way to regulate the communication between vehicles at both ends of a train subset. Miller et al., U.S. Patent No. 3, November 30, 1976,
No. 994,459 uses a wireless system to communicate between a vehicle disconnected from the train and the rest of the train.
However, U.S. Pat. No. 3,993,459 does not mention any other communication between train cars using radio signals.

Another factor that affects reliability is the increase in the amount of information mentioned above. Even if everything else is uniform, the amount of information increases and the overall reliability tends to decrease. In summary, this train communication system seeks to provide reliability in two ways. One is that it provides excellent reliability with cable connectors between vehicles, but it complicates vehicle connection and disconnection. The other is to use coupler pins for ease of operation, but this leads to high maintenance costs to maintain proper reliability. Coupling pins are susceptible to environmental factors and other problems. The rate of communication failures caused by connector pins, especially the rate of intermittent failures, is by far the highest. Although increasing the number of wires is effective up to a certain point, this method is limited by the number of factors. The most important problem with these factors is the large number of electrical connections between vehicles, which are often connected and disconnected. Such a connection trades reliability and automation for at best, and reliability and / or automation decreases as the number of wires increases. As the amount of information processed by each wire increases, there is no need to increase the number of electrical connections between vehicles. However, as the amount of information transmitted by each wire increases, current technology suffers from reliability issues with large amounts of information flowing through the combiner pins, making data more prone to damage and increasing maintenance numbers.

[0007]

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a communication link between the cars of a train and overcome the drawbacks of the prior art. Another object of the invention is to provide a new communication link, including a wireless link over free space. Yet another object of the present invention is to provide a new communication link that includes a multiplexer and a demultiplexer on a train's select vehicle.

[0008]

SUMMARY OF THE INVENTION A communication link of the present invention for solving the above-mentioned problems is a communication link that enables communication between adjacent vehicles of a multi-vehicle transportation means.
The link is linked to at least a first vehicle of the vehicles
(A) (i) various systems on the first vehicle, the first multiplex transmission (multiplexing) / multiplexing (demultiplexing) means comprising: The first digital signal, which is an expression of the status signal or control signal, is multiplexed and processed as the first digital train line signal, and (ii) the first digital train line signal is processed. First changing means for changing to a first radio frequency signal, and (iii) a first antenna arranged at one end of the first vehicle for transmitting the first radio frequency signal, (iv) ) A second radio frequency signal is converted into a second digital train line signal by the first multiplex transmission / demultiplexing means and is a representation of status signals or control signals of various systems of the second vehicle. Supply the digital signal of (v) The second radio frequency signal is received by the first antenna, the second vehicle of the multi-vehicle means has a second multiplexing / demultiplexing means,
(B) (i) multiplex-transmitting the second digital signal, processing the second digital signal as a second digital train line signal, and (ii) the second digital train line signal. Second changing means for changing the digital train line signal of the above into a second radio frequency signal,
(iii) a second antenna which is arranged at an end of the second vehicle adjacent to an end of the first vehicle where the first antenna is arranged and which transmits the second radio frequency signal. , (Iv)
By the second multiplex transmission / demultiplexing means the first
Changing the radio frequency signal of the first digital train circuit signal to a first digital train line signal and providing a first digital signal that is a representation of a status signal or control signal of the various systems of the first vehicle; (v) the second signal Receiving the first radio frequency signal by means of an antenna of the first vehicle to the second vehicle and from the second vehicle to the first vehicle of the multi-vehicle vehicle, First and second
Transmitting communication through free space radio frequency coupling through the antenna of, the link being disposed in the first vehicle, the first housing enclosing the first antenna, and the second vehicle. A second housing enclosing the second antenna, the first housing having first shield means enclosing the first antenna, the second housing
Of the housing has second shield means surrounding the second antenna, the first and second housings each have an open end, and the open ends of the first and second housings are mutually It is characterized in that it is arranged so as to face.

[0009]

Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows a free space communication link 15 which allows free communication between vehicles 3 and 5. Each vehicle includes a train line multiplexer (TMX) 17 'and 17 "and a radio link transmitter (RLT) 19' and 19". As shown in FIG. 2, the multiplexer 17 includes a monitoring system 21, a braking system 23, and a propulsion system 2.
5, receiving samples of digital signals from different train systems such as ventilation system 27, intercom system 29, etc. These signals are arranged in a predetermined order to form a frame, such as a 125 microsecond length. As shown, each frame includes a frame synchronization signal at the beginning of the frame. These signals are transmitted to different vehicles, typically adjacent vehicles, by a transmitter that transmits the signals over a communication link. At the receiving end, the demultiplexer converts the digital signals into various train systems, namely the monitoring system 21, the braking system 2
3. Supply to propulsion system 25, ventilation system 27, intercom system 29. The multiplexer and demultiplexer systems are, of course, well known to those skilled in the art and need not be detailed.

As shown in FIGS. 3 and 4, the output of TMX is supplied to the modulation unit of the RLT. FIG. 3 shows a direct modulation unit and FIG. 4 shows an indirect modulation unit. Each unit includes a line interface 31 or 41 and a signal processor 33 or 43. These units process the signal and make it available for use in the modulator. For this reason, if the 0-sequence of the signal is long, the signal must be modulated to include 1's and 0's, such modulation being provided by line interfaces 31, 41 and signal processor 33,
At 43. Next, FIG. 3 will be described. The output of signal processor 33 is provided to modulator 37. Modulator 37 has a second input terminal provided by RF generator 35. The output of the modulator 37 is supplied to the bandpass filter 39, and the output of the bandpass filter 39 is supplied to the duplexer shown in FIG. Next, FIG. 4 will be described. The output of signal processor 43 is provided to modulator 47. However, in this case, the second terminal of the modulator 47 is supplied from the IF source 45. The output of the modulator 47 is transmitted again via the bandpass filter 49, and the output of the bandpass filter 49 is supplied to the mixer 53. The second input terminal of the mixer is supplied from the RF generator 51, and the output of the mixer 53 is supplied to the bandpass filter 55. Bandpass filter 55
The output of is supplied to the duplexer.

FIG. 5 is a diagram showing an aspect of the receiver portion of the RLT. The output of the duplexer is supplied to the bandpass filter 57, and its output is supplied to the mixer 59. The received signal is mixed with the RF signal from the RF generator 61 applied to the second terminal of the mixer 59. The output of the mixer 59 is supplied to the bandpass filter 63, and its output is supplied to the demodulator 65. The synchronization signal is supplied from the demodulator 65 to the symbol / bit clock recovery circuit 67, and the demodulator 65 is supplied.
And the output of the symbol / bit clock recovery circuit 67 is provided to the signal processor 69. The output of the signal processor 69 is supplied to the line interface 71, and its output is supplied to the TMX. FIG. 6 shows a duplexer 77, a transmitter 73 and a receiver 75, which are clear from the figure. Next, FIG. 7 will be described. The free space electromagnetic link 15 between the vehicles 7'and 7 '' is achieved by RF antennas 83 'and RF83'', respectively. In particular aspects, housings 79 'and 79 "
The housing is made of a dielectric material such as polycarbonate. Each housing consists of a sealed enclosure that protects it from humidity and moisture damage.

Metal shields 81 'and 81 "are arranged around the housings 79' and 79". As shown, metal shields 81 'and 81 "
Does not extend across the front of the housings 79 'and 79 ". Ie housings 79 'and 7
The 9 ″ parts face each other. However, the metal shields 81 'and 81 "extend around the RF antennas 83' and RF83", so that the metal shields 81 'and 81 "can extend from the RF antennas 83' and RF83" in any direction from one vehicle to another. It prevents spurious dispersion of RF signals and prevents RF antennas 83 'and RF83 "from receiving spurious electromagnetic signals, except for signals originating from the vehicle at the other end. The metal shield comprises conductor elements 85 and 8
It also includes 5'to prevent backward transmission, i.e. reception from the rear. The connector cables 87 'and 87 "connect the RF antennas 83' and RF83" to the RLT of each vehicle.
Connect to the unit. The coupler is located outside the vehicle,
When vehicles are coupled to each other, they physically approach each other. The coupler is moisture and waterproof sealed and protected from flying stones by housings 79 'and 79 "and metal shields 81" and 81 ".

Housings 79 'and 7 shown in FIG.
9 ″ requires a particular type of antenna. If the antenna is small enough, it need not be protected by the housing as described above. In fact, it is also possible to install the housing inside the vehicle, depending on the situation. Therefore, the housing described above is for a particular situation.

[0014]

The device of the present invention does not suffer from the physical drawbacks of pin and spring devices and has the advantage that it does not have to be operated in a dirty environment. In addition, since the wireless system eliminates the need for many electrical connections between vehicles, reliability will not be lost even if a large amount of information flows, data will not be lost, and the number of maintenance will be reduced. Also effective. Although specific embodiments have been described herein, it is for the purpose of illustration only and not to limit the invention. Obviously, various modifications can be easily made by those skilled in the art without departing from the scope of the invention defined in the appended claims.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing the circuit of two consecutive trains of a train linked by a wireless link.

FIG. 2 is a detailed diagram showing a train line multiplexer (TMX).

FIG. 3 is a block diagram of a radio link transceiver (RLT) direct modulation transmitter.

FIG. 4 is a block diagram of an indirect modulation type transmitter of a radio link transceiver (RLT).

FIG. 5 is a diagram illustrating certain aspects of an RLT receiver.

FIG. 6 is a diagram showing a transmission / reception switch that constitutes a part of the RLT.

FIG. 7 is a detailed view showing a wireless link between vehicles at both ends.

[Explanation of symbols]

3, 5, 7 ', 7 "Vehicle 15 Free space communication link 17, 17', 17" Train line multiplexer (TMX) 19 ', 19 "Radio link transmitter (RLT) 21 Monitoring system 23 Brake system 25 Propulsion system 27 Ventilation system 29 Intercom system 31, 41 Line interface 33, 43, 69 Signal processor 35, 51, 61 RF generator 37 Modulator 39, 57, 63 Band filter 45 IF source 47 Modulator 49, 55 Band filter 51 RF generator 53, 59 Mixer 65 Demodulator 67 Symbol / bit clock recovery circuit 71 Line interface 73 Transmitter 75 Receiver 77 Duplexer 79, 79 ″ Housing 81 ′, 81 ″ Metal shield 83 ′, 83 ″ RF RF amplifier Tena

Claims (3)

[Claims] 1. A communication link for allowing communication between adjacent vehicles of a multi-vehicle means, said link comprising a first multiplex transmission / demultiplexing means on at least a first vehicle of said vehicles, The first multiplexing / demultiplexing means (A) (i) multiplexes a first digital signal, which is a representation of status signals or control signals of various systems, on the first vehicle, and The second digital train line signal is processed as a first digital train line signal, and (ii) first changing means for changing the first digital train line signal to a first radio frequency signal; and (iii) the first vehicle. A first antenna disposed at one end of the second radio frequency signal for transmitting the first radio frequency signal, and (iv) a second digital signal for transmitting a second radio frequency signal by the first multiplex transmission / demultiplexing means. Converted to a train line signal and used by the second car Providing a second digital signal which is a representation of various system status signals or control signals, and (v) receiving the second radio frequency signal by the first antenna and providing a second of the plurality of vehicle means. Vehicle has a second multiplexing / demultiplexing means,
(B) (i) multiplex-transmitting the second digital signal, processing the second digital signal as a second digital train line signal, and (ii) the second digital train line signal. Second changing means for changing the digital train line signal of the above into a second radio frequency signal,
(iii) a second antenna which is arranged at an end of the second vehicle adjacent to an end of the first vehicle where the first antenna is arranged and which transmits the second radio frequency signal. , (Iv)
By the second multiplex transmission / demultiplexing means the first
Changing the radio frequency signal of the first digital train circuit signal to a first digital train line signal and providing a first digital signal that is a representation of a status signal or control signal of the various systems of the first vehicle; (v) the second signal Receiving the first radio frequency signal by means of an antenna of the first vehicle to the second vehicle and from the second vehicle to the first vehicle of the multi-vehicle vehicle, First and second
Transmitting communication through free-space radio frequency coupling through the antenna of, the link being disposed in the first vehicle, the first housing enclosing the first antenna, and the second vehicle. A second housing enclosing the second antenna, the first housing having first shield means enclosing the first antenna, the second housing
Of the housing has second shield means surrounding the second antenna, the first and second housings each have an open end, and the open ends of the first and second housings are relative to each other. A communication link characterized by being arranged so as to face the. 2. The multiplex transmission means of the first vehicle performs the function of a demultiplexer, the demultiplexer of the second vehicle performs the function of a multiplexer, and the first vehicle has a receiving means. However, the second vehicle has a transmission means, thereby transmitting communication from the first vehicle to the second vehicle and from the second vehicle to the first vehicle. The communication link according to item 1. 3. The communication link of claim 3, wherein the first and second vehicles comprise adjacent vehicles of the multi-vehicle vehicle.