JP3118068B2 - Train position detection device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a train position detecting apparatus, and more particularly to a train position detecting apparatus which detects a train using a track circuit and provides information to a block section behind the train.

[0002]

2. Description of the Related Art Conventionally, a train position detecting device using a track circuit uses a rail of a block section formed by dividing rails (tracks) at predetermined lengths as a part of a track circuit, and forms a block of the block section. A transmitter that transmits a signal of a predetermined frequency is connected to the start end (the side where the train enters), and a receiver that receives the signal is connected to the end side (the side where the train enters) of the block section. Have been.

[0003] In the above configuration, when a train is present in the block section and the rail is short-circuited by the axle (wheel) of the train, the output level of the receiver decreases, while no train exists in the block section. At that time, the output of the receiver is maintained at a predetermined height. Therefore, if the track relay is turned on and off by the output of the receiver, the presence or absence of the train in the block section can be detected in the on / off state.

[0004] The above-mentioned block section is electrically insulated from an adjacent block section by an impedance bond or the like with respect to an AC signal so as not to interfere with a train detection signal in the adjacent block section. It is devised. Also,
If the AC signal is formed so as to be electrically non-insulated, interference is prevented by making the frequencies of the detection signals used in adjacent block sections different from each other.

[0005]

However, in the above-mentioned conventional train detection device using a track circuit, the rails forming a part of the track circuit are in an environment that is susceptible to noise, so that the S / N ratio is low. There is a drawback that the circuit configuration tends to be low, the carrier frequency is changed in order to eliminate mutual interference with adjacent tracks, and a resonance circuit is provided at the track boundary. In addition, in the conventional train position detection device, the signal for train detection, when giving information to other uses, for example, to the block section behind, to transmit the phase inverted, etc. One kind and a synchronous signal line were required. In addition, another method has been disadvantageous in that the equipment cost is increased because the communication is performed by using a separately installed communication equipment.

The present invention has been made in order to solve the above-mentioned drawbacks, and has as its object to detect a train position with high noise resistance, to have no mutual interference with an adjacent track circuit, and It is an object of the present invention to provide a train position detecting device capable of transmitting information.

[0007]

In order to achieve the above object, a train position detecting apparatus according to the present invention comprises: first signal spreading means for spreading a predetermined transmission signal with a first PN code; Second signal spreading means for spreading a predetermined transmission signal with the first PN code having a phase difference from the first PN code and a second PN code of a different type; and the first and second signal spreading means. Sending means for sending the spread signal spread by the signal spreading means to the starting end of the rail forming the track circuit; receiving means for receiving the spread signal from the end of the rail;
The received signal received by the receiving means is demodulated using a signal having the same frequency as the transmission signal, and the first and second signals are demodulated.
Extracting means for extracting a PN code corresponding to the first PN code from the signal extracted by the extracting means; and detecting the PN code corresponding to the first PN code from the signal extracted by the extracting means; A second detecting means for detecting a PN code that matches the second PN code; a phase difference detecting means for detecting a phase difference between the PN codes detected by the first and second detecting means; Detecting means for detecting the presence or absence of a train on the rail by detecting the presence or absence of the detection means or the second detection means, and when the phase difference detection means detects a phase difference, information corresponding to the phase difference Information output means for outputting.

[0008]

In the above construction, the spread signal spread by the first and second signal spreading means is supplied to the starting end of the rail forming the track circuit by the sending means. When there is no train on the rail, the reception signal received from the terminal end of the rail is demodulated using the transmission signal to extract the PN code used in the first and second signal spreading means. You. Next, the detecting means includes the first detecting means or the second detecting means.
The presence of a train is detected when the PN code used in the first signal spreading means is present in the extracted signal detected by the detecting means. On the other hand, when there is a train on that rail,
The reception level of the receiving means is low, so that the extracting means does not extract the PN code. For this reason, the detection means
And detecting the presence of a train on the condition that the PN code is not detected by the second detection means. Further, the phase difference detecting means detects a phase difference between the first and second PN codes when no train exists on the rail. Then, the information output means outputs information corresponding to the detected phase difference.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic configuration diagram of a train position detecting device according to one embodiment, in which a track (corresponding to a rail of the present invention, hereinafter referred to as a rail) T is a block section at predetermined intervals (in FIG. 3 around the block interval T _i to simplify
Only block segments are shown. ) T _i , T _i−1 ,
T _{i + 1} .

Each block section T _i , T _i-1 , T _{i + 1} may be a section using a known impedance bond, or may be a non-insulated section in which a capacitor or the like is interposed between rails.

[0011] The embodiment apparatus, because it is placed in each block section, will be described below train position detection device corresponding to the block section T _i.

First, as the transmission equipment, the signal generator 1
a, first and second spreading circuits 2a and 2b, an adding circuit 3, and a transmitter 4. The signal generator 1a converts a non-modulated or predetermined transmission signal into a normal AM or FM signal using a modulation circuit.
Carrier modulated (equivalent to the transmission signal of the present invention)
(F _ci ) is output to the first and second spreading circuits 2a and 2b.

The first spreading circuit 2a has a predetermined PN code (P
N _i ) from the first PN code generator 5 a
After the carrier (f _ci ) is spread using the PN code, it is output to the next adder 3. Also,
The second spreading circuit 2b is a PN code different from the PN code (PN _i ), and has a predetermined phase difference from the PN code (PN _{i ′} (θ _{i ″} )) (θ _{i ′} ). _' Represents a phase difference from the first PN code and corresponds to the information. This phase difference will be described later.)
Using the second PN code from the code generator 6a, the carrier (f
_ci ) is configured to be output to the next adder circuit 3 after spreading processing.

The transmitter 4 is formed of a known amplifier, and is configured to supply an output to the starting end A of the rail T.

Next, the receiving equipment includes a receiver 10, a demodulation circuit 11, a filter circuit 12, a pair of matched filters 13a and 13b, and a phase detector 14. The receiver 10 is formed of a known amplification circuit, and is configured to output its output signal to a demodulation circuit 11.

The demodulation circuit 11, divided by using the output from the signal generator 1b of the signal generator 1a outputs the same carrier (f _ci) a carrier that sent the respective spreading circuit 2a, the 2b (f _ci) It is configured to perform arithmetic processing.

The filter circuit 12 is formed of a well-known low-pass filter, filters the output from the demodulation circuit 11 and performs first and second matched filters 13a, 13a.
13b.

The matched filters 13a and 13b are formed from a well-known correlation matched filter circuit,
A PN code (PN) similar to that of the second PN code generators 5a and 5b
_i , PN _{i ′} (θ _{i ″} )), respectively, and detects a coincidence state with the PN code (PN _i , PN _{i ′} (θ _{i ″} )) from the filter circuit 12 to switch the track relay TR. It is configured to be driven. When the transmitting and receiving facilities are installed in the same equipment room, each of the signal generators 1a and 1b and the first and second PN code generators 5a, 5b, 6a and 6b are each configured as a single unit, and A carrier and a PN code can be supplied to the circuits 2a and 2b, the demodulation circuit 11, and the matched filters 13a and 13b, respectively.

When the first matched filter 13a detects the PN code (PN _i ), the phase detector 14 detects that the train a does not exist in the section T _i by lifting the track relay TR and closing it. When the PN code (PN _i ) is not detected, the track relay TR is dropped to block the section T _i.
Is configured to detect the presence of a train a. Also, the operation of the TR, displays select current-falling and based on information obtained from the phase difference block section T _i traffic to be built at the end side of the. Further, each matched filter 13a,
13b detects the time difference when each PN code (PN _i , PN _{i ′} (θ _{i ″} )) is detected, that is, the phase difference between the two PN codes to obtain information. And the information, sends predetermined information to the block section T _i-1 of the rear based on the state of the TR, e.g., the current示信No. contents of traffic closed Suk interval T _i, determines the transmission information T _i-1.

The frequency of the carrier wave (f _ci ) is made different from that of the adjacent block sections T _i-1 and T _{i + 1} , which is the same as that of a conventional train position detecting device using a track circuit.
Differentiating the type of code or the phase of the PN code is a feature provided by the configuration of the present invention.

[0021] Here, to differentiate the type of PN code, for example, when using the two PN codes of the m-sequence code in block section T _i is the block section T _i-1 to the right, The PN code is to use another two codes of the m sequence having the same code length.

When the phases of the PN codes used in the same block section are made different, as shown in FIG.
The PN codes (PN _i ) of the PN code generators 5a and 5b and the second
The PN code (PN code) of the PN code generators 6a and 6b
_i is to have a theta _{i ''} difference between _{'(θ i''))} .
It is to be noted that when θ _{i ″} is, for example, 2 bits of a PN code, the Y indication (yellow indication) is 4 bits for the rear block section T _i−1 , which is Y · The meaning is given to be the information of the G presentation (yellow, blue presentation).

In the present embodiment, the carrier (f _ci )
Is different from the adjacent block sections T _i-1 and T _{i + 1,} and the PN code is used for each block section T _i , T _{i + 1} .
Different PN codes are used for T _i-1 and T _{i + 1} , and different types of PN codes are used with different phases even in the same block section. Therefore, transmission and reception can be performed without interference between adjacent block sections. Further, in order to simplify the apparatus, the carrier f _ci may be the same in each block section, and the mutual interference can be reduced accordingly.

Next, the detecting operation of the apparatus according to the present embodiment will be described. First, a description will be given of a case where the block section T _i no trains a.

The carrier (f _ci ) transmitted from the signal generator 1 is applied to each PN code (P) by each of the spreading circuits 2a and 2b.
N _i , PN _{i ′} (θ _{i ″} )), and after being subjected to spreading processing to become a spread signal, superimposed by the adder 3 and supplied to the start end A of the rail T via the transmitter 4. You.

At the terminal side B of the rail T, there is a spread signal including a carrier with attenuation due to the length of the rail T. Then, the spread signal is subjected to amplification processing in the receiver 10 and then demodulated using the carrier (f _ci ) in the demodulation circuit 11 to perform spread processing (PN _i , PN _{i ′} (θ _{i ″} )). Is extracted and filtered by the filter circuit 12, and the original PN code (PN _i , PN _{i ′} (θ _{i ″} )) is extracted.

Next, each matched filter 13a, 13
b indicates that the PN code (PN _i ,
PN _{i ′} (θ _{i ″} )) is detected and sent to the phase detector 14. Then, when the phase detector 14 detects the first PN code (PN _i ), it lifts the track relay TR. In this case, for example, even if noise caused by commercial power supply harmonics or noise transmitted from a train running on another track adjacent to the track T exists in the block section T _i , the noise is ignored. Since a detection output can be obtained, a train position detection with extremely high noise resistance can be performed.

The phase detector 14 detects two PN codes (P
N _i , PN _{i ′} (θ _{i ″} )) and when the phase difference θ _{i ″} between both PN codes is detected, information corresponding to the θ _{i ″} and the state of TR is written to the following information. It is transmitted for the block section T _i-1 .

On the other hand, if the train a exists in the block section T _i , the rail T is short-circuited by the axle of the train a, so that the level of the spread signal on the terminal side B is small, and the output level of the receiver 10 is also small. . Therefore, the phase detector 14 cannot maintain the lifting of the track relay TR and falls. The section T _i where train a is blocked by the fall of the track relay TR
You can know that existed. In this case, both PN
Since the code (PN _i , PN _{i ′} (θ _{i ″} )) is not detected, the information of the next block Ti ₋₁ is converted from the information “TR fall of Ti” into θ _{i ″} and transmitted.

In the above embodiment, the train position detection uses the first PN code (PN _i ), but may use the second PN code (PN _{i ′} (θ _{i ″} )). Therefore, in the present invention, the term “first detecting means” or “second detecting means” includes the case where both detecting means detect.

[0031]

According to the present invention, there is provided a train position detecting apparatus comprising: first signal spreading means for spreading a predetermined transmission signal with a first PN code; and transmitting the predetermined transmission signal to the first PN code. A second signal spreading means for performing a spreading process with a second PN code having a phase difference, and a spread signal spread by the first and second signal spreading means is sent to a starting end of a rail forming a track circuit. Sending means, receiving means for receiving the spread signal from the terminal end of the rail, and demodulating a received signal received by the receiving means using a signal having the same frequency as the transmission signal; Extracting means for extracting the second spread signal; and extracting the first signal from the signal extracted by the extracting means.
First detecting means for detecting a PN code that matches the PN code of
Second detecting means for detecting a PN code that matches the N code, phase difference detecting means for detecting a phase difference between the PN codes detected by the first and second detecting means, and the first detecting means Or detecting means for detecting the presence or absence of a train on the rail based on the presence or absence of the detection of the second detecting means, and information for outputting information corresponding to the phase difference when the phase difference detecting means detects a phase difference. The output means makes it possible to provide a train position detecting device having high noise resistance and no mutual interference with the adjacent track circuit, and to transmit information. Further, a configuration in which a synchronous line is unnecessary on the transmission side and the reception side can be adopted.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an apparatus according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a phase difference of a PN code.

[Explanation of symbols]

1a, 1b Signal generators 2a, 2b First and second spreading circuits (first and second spreading means) 3 Addition circuits 4 Transmitters (sending means) 5a, 5b, 6a, 6b First and second PN code generators Reference Signs List 10 receiver (receiving means) 11 demodulation circuit (extraction means) 13a, 13b first and second matched filters (first and second detection means) 14 phase detector (phase difference detection means, information output means)

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-61-211162 (JP, A) JP-A-59-1458 (JP, A) JP-A-60-4340 (JP, A) (58) Field (Int.Cl. ⁷ , DB name) B61L 1/00-29/32

Claims (1)

(57) [Claims] A first signal spreading unit that spreads a predetermined transmission signal with a first PN code; and the first PN code having a phase difference from the first PN code. A second signal spreading means for performing a spreading process using a second PN code of a different type, and a spread signal spread by the first and second signal spreading means to a starting end of a rail forming a track circuit. Sending means, receiving means for receiving the spread signal from the end of the rail, and demodulating the received signal received by the receiving means using a signal having the same frequency as the transmission signal, Second
Extraction means for extracting a PN code of the following; first detection means for detecting a PN code that matches the first PN code from a signal extracted by the extraction means; A second detection unit that detects a PN code that matches the second PN code; a phase difference detection unit that detects a phase difference between the PN codes detected by the first and second detection units; Detecting means, or detecting means for detecting the presence or absence of a train on the rail based on the detection of the second detecting means, and information corresponding to the phase difference when the phase difference detecting means detects a phase difference. A train position detecting device comprising: an information output unit that outputs the information.