JP5441218B2 - Track circuit device - Google Patents

Description

  The present invention relates to a track circuit device in the railway field. Specifically, the present invention is connected to any section that divides a track on which a train travels, and a train detection signal (TD wave) is made to flow in the corresponding section. The present invention relates to a track circuit device that detects presence or absence.

There are two types of track circuit devices (for example, see Non-Patent Document 1), and an AC AF track circuit uses a commercial frequency or an AC signal having a predetermined frequency as a train detection signal ( For example, see Patent Documents 1 to 3).
FIG. 3 shows a portion of the conventional track circuit device that is useful for explaining the present invention. FIG. 3A is a block diagram of the track circuit device 20, and FIG. A waveform example, (c) is a spectrum of the train detection signal A.

  The main role of the track circuit device 20 is that if the track on which the train 10 travels is divided into several sections 11, 12, and 13 and is connected to the section 12, of which the train 10 in the connected section 12 For this purpose, the track circuit device 20 includes a logic unit 21 including an initial setting circuit 22 and a level drop climbing determination circuit 23, and a signal generation circuit 31. A transmitting device 30 for sending A to the track section 12 and a receiving device 40 having a level detection circuit 41 and receiving the train detection signal A from the track section 12 and generating a level signal B (basic information for determination). And has.

  In this track circuit device 20, not only the logic unit 21 but also the signal generation circuit 31 and the level detection circuit 41 are digitized. Therefore, the transmission device 30 has, as the signal generation circuit 31, a carrier waveform memory 32 that holds a sinusoidal carrier waveform that is the original form of the train detection signal A as a digital value, and a waveform value read from the memory 32. And a pulse width modulator 33 (PWM) for generating a pulse width modulation signal in response thereto. In addition, in order to convert the pulse width modulation signal into an analog train detection signal A, the transmission device 30 removes the harmonics, for example, a power amplifier 34 composed of a class D amplifier circuit, and an AC component of the basic carrier frequency fo. Only a low-pass filter 35 (LPF) that outputs only the train detection signal A is provided.

  The train detection signal A output from the transmission device 30 is transmitted via a transformer 36 that secures a withstand voltage between the device and the outside, a signal cable 37 for outdoor use, and a transformer 38 that secures a withstand voltage between the cable and the track. Thus, it is fed into one end of the track section 12. Further, the train detection signal A is transmitted from one end side to the other end side in the track section 12 if the train 10 is not present in the track section 12, and the track and cable are transmitted from the other end portion of the track section 12. It reaches the receiving device 40 through a transformer 48 that secures a dielectric strength voltage between the external device 47, an outdoor cable 47, and a transformer 46 that secures a dielectric strength voltage between the outside and the device.

When the train 10 is present in the track section 12, the train detection signal A is received because the train detection signal A in the track section 12 is cut off due to a short circuit in the wheel or axle of the train 10. It also prevents it from reaching the device 40.
The receiving device 40 includes a power amplifier 45 (AMP) and an A / D converter 44 (ADC) in order to receive the train detection signal A transmitted and convert it from analog to digital. . In addition, the receiving device 40 includes, as the level detection circuit 41, a band pass filter 43 (BPF) that extracts a signal component of the carrier frequency fo from the digitized train detection signal A and a level signal B that indicates the level of the extracted signal. And a rectifier 42 to be generated.

  The level drop-up determination circuit 23 of the logic unit 21 generates a train detection signal C from such a level signal B and provides it to on-line information processing of a higher-level device such as a CTC or an interlocking device. When the time over which the level signal B as the judgment basic information exceeds a predetermined level that has been determined in advance exceeds the base time, the value of the train detection signal C is set to the train absent line state, and the level as the judgment basic information When the time during which the signal B is lower than a predetermined level continuously exceeds the element when falling, the value of the train detection signal C is set to the train detection state. In addition, the time of falling on the train detection side that requires attention in train operation is determined in advance in a short time such as 500 ms, and the time of falling on the side where the train is not present is determined in advance in a relatively long time such as 1000 ms to 1100 ms. .

  The initial setting circuit 22 of the logic unit 21 performs necessary initialization. For example, the apparatus is configured so that the train detection signal A of the track section 12 can be frequency-discriminated from the train detection signals of the other sections 11 and 13. If the frequency fo is selected for the train detection signal A of the track circuit device 20 at the time of new installation or replacement adjustment, data necessary for generating the train detection signal A of the frequency fo is generated at the time of starting the device. In addition to being set in the waveform memory 32, parameters and the like necessary for extracting a signal component of the frequency fo from the received train detection signal A are set in the bandpass filter 43.

  The track circuit device 20 having such a configuration is connected to both ends of the track section 12 via the cables 37 and 47, and when the operating power is supplied, the carrier waveform memory 32, the bandpass filter 43, and the like are initialized. Then, the train detection signal A having the carrier frequency fo is transmitted from the transmission device 30 to the track section 12. When the train 10 is not present in the track section 12 or when the train 10 exits the track section 12, the train detection signal A is received and received by the receiving device 40 while maintaining a sufficient amplitude, and the level is reflected. Since the signal B exceeds a predetermined level, the train detection signal C becomes in a train absent line state after the elapse of time on the landing. On the other hand, when the train 10 advances to the track section 12, the train detection signal A is cut off in the track section 12 due to a track short circuit between the wheel and the axle of the train 10, and a level signal reflecting this is transmitted. Since B is below the predetermined level, the train detection signal C enters the train detection state after the elapse of the fall. In this way, the presence or absence of a train is detected at any time.

  The track circuit device 20 having the basic configuration described above uses a simple signal having a sine wave shape and a constant frequency as the train detection signal A. However, the train track detection is such that a telegram signal is transmitted and received via the track section. There is also a system (see, for example, Patent Document 4). This so-called telegram transmission / reception system employs a system configuration in which a plurality of common transmission / reception devices and a ground control device are connected via a data transmission path. Then, different telegrams are sent to individual transmission devices by the ground control device, and further, the telegrams are subjected to MSK modulation and then sent to the orbit. Further, the receiving device demodulates the electronic message and delivers it to the ground control device via the transmission path. Such a message transmission / reception method is intended for the common use of transmission / reception devices and the advancement of the train detection function, but it is necessary to change the information content of the message signal for each transmission device, and whether there is a train. Since the determination timing is limited after completion of transmission / reception of the message, the set unit time of the falling element or the flying element cannot be made shorter than the transmission / reception time of the message.

  There is also a track circuit device that uses narrow band FSK (Frequency Shift Keying), which is a kind of digital modulation method, for the train detection signal A (see, for example, Patent Document 5). In this so-called bit transmission / reception system, alternating signals with two types of transition frequencies (fo ± 2 Hz) are used. Then, by checking the complementarity of the alternating modulated wave on the receiving side, an attempt is made to prevent unauthorized uplifting of the train existing line as an absent line even in the case of malfunction due to noise. The specific content of the verification of the complementarity of the modulated wave is not clear, but it seems to confirm that the received value changes for every bit and continues for a predetermined time including many bits. In that case, the set unit time of the falling element and the lifting element cannot be made shorter than the complementary verification time.

JP 2000-168554 A JP 2005-262895 A JP 2008-265626 A JP 2002-225707 A JP 2009-179214 A

"Introduction to Signals for Railway Electricians Signal Series 9 Track Circuit" published by Japan Railway Electrical Engineering Association

  By the way, the track circuit is required to stably maintain the falling state (train detection state) and the lifting state (train absent line state) in the process of determination of the falling anchorage (train presence / absence determination) based on the transmission / reception result of the train detection signal. There is. This is because maintaining the stable uphill state (train absent line state) has the advantage that the operating rate of train operation is secured at a desirable high value, and in maintaining a stable fall state (train detection state) This is because there is an advantage that the safety of train operation is secured at a high level. Nonetheless, excessive stability in the upright state (the state where the train is absent) may impair safety by preventing a smooth state transition from the upside to the downside. Moreover, excessive stability in the fall state (train detection state) may hinder smooth state transition from the fall to the roof, and may reduce the operation rate.

Therefore, it is necessary to accurately determine and maintain the above two states in a balanced manner, but the balance is affected by the difference in detection priority between both states in addition to the manifestation characteristics of both states. Therefore, realization is not simple.
And in the conventional track circuit device, in order to realize it, the time element for continuity detection can be individually set by dividing it into a falling time element and a lifting time element as described above. In the binarization of the level signal, a hysteresis characteristic is also given.

However, as long as it stays in the so-called continuity detection method of investigating whether the climbing state (train absent line state) and falling state (train detection state) are continuous over the time indicated by each time element, It is not possible to accurately classify the intermittent state in which the uphill state (the train absent line state) lasts for a shorter time than the uplifting element and the falling state (the train detection state) lasts for a shorter time than the falling element.
However, such an intermittent state is likely to be manifested when frequency-modulated noise, which has been a problem in recent years, particularly noise having an alternating characteristic, is on track, so that the intermittent state is accurately classified. For example, an immediate implementation of the intermittent detection method is desired.
Therefore, it is a technical problem to realize a track circuit device that can accurately detect a train detection signal up to intermittentness in addition to continuity.

  The track circuit device of the present invention (Solution means 1) was devised to solve such a problem, and includes a transmitter that sends a train detection signal to a corresponding section of the track, and the train detection from the section. In a track circuit device including a receiving unit that receives a signal and detects basic determination information from the received signal, and a logical unit that determines the presence or absence of a train in the section based on the basic determination information, the logical unit includes: A drop counter that counts the number of times that the judgment basic information indicates that there is a train, and an up counter that counts the number of times that the judgment basic information indicates that there is no train, and the value of the up counter is When the threshold value is exceeded, a train absence line is determined, and when the value of the fall counter exceeds the threshold value, the train detection is determined. When the determination basic information indicates that there is no train continuously over the number of values, the fall counter is cleared, and continuously over the number of times of the up / down intermittent threshold value that is smaller than the up / down time corresponding threshold value. When the judgment basic information indicates that there is a train, the uplift counter is cleared.

  The track circuit device of the present invention (Solution means 2) is one in which the clearing condition of the drop counter is left out of the above solution means 1 and the clearing condition of the lifting counter is omitted. A transmission unit that transmits a train detection signal, a reception unit that receives the train detection signal from the section and detects basic determination information from the reception signal, and determines whether there is a train in the section based on the basic determination information In the track circuit device, the logic unit includes a fall counter that counts the number of times that the determination basic information indicates that there is a train, and a lift counter that counts the number of times that the determination basic information indicates that there is no train When the value of the above-mentioned counter is above the threshold value corresponding to the trapping time element, a train absent line is judged, and when the value of the above-mentioned falling counter exceeds the threshold value corresponding to the base element when falling, the train detection is performed. When the basic information indicates that there is no train continuously over the number of times of the falling intermittent threshold value smaller than the falling time corresponding threshold value, the falling counter is cleared. And

  The track circuit device of the present invention (Solution means 3) is one in which the clear condition of the drop counter is left out of the above solution means 1 and the clear condition of the lift counter is left. A transmission unit that transmits a train detection signal, a reception unit that receives the train detection signal from the section and detects basic determination information from the reception signal, and determines whether there is a train in the section based on the basic determination information In the track circuit device, the logic unit includes a fall counter that counts the number of times that the determination basic information indicates that there is a train, and a lift counter that counts the number of times that the determination basic information indicates that there is no train When the value of the above-mentioned counter is above the threshold value corresponding to the trapping time element, a train absent line is judged, and when the value of the above-mentioned falling counter exceeds the threshold value corresponding to the base element when falling, the train detection is performed. When the basic judgment information indicates that there is a train continuously over the number of times of the up / down intermittent threshold value smaller than the upside time element correspondence threshold value, the uplift counter is cleared. It is characterized by.

  Further, the track circuit device of the present invention is (tracking means 4), which is the track circuit device of the above-described solving means 1 to 3, wherein the transmitting unit is continuous with transmission frame data having a bit string composed of a plurality of bits as a unit frame. The train detection signal is generated by repeatedly frequency-modulating a carrier wave, and the reception unit is configured to generate a plurality of frames with a frame reproduction period shorter than a transmission / reception time of the unit frame from a bit string reproduced by frequency demodulation from the reception signal. The received frame data is generated by extracting bits and included in the basic determination information, and the logic unit processes the received frame data with a frame determination period shorter than the transmission / reception time of the unit frame. It is characterized by being.

  Further, the track circuit device of the present invention (solving means 5) is the track circuit device of the above-described solution means 4, wherein the logic unit performs processing on the received frame data in the frame unit for each frame data. In addition to determining the validity of the data, the validity of the periodic change of the data value over a plurality of frame data is also determined.

  Further, the track circuit device of the present invention (Solution means 6) is the track circuit device of the above solution means 4 and 5, wherein the transmission frame data includes bit patterns having different numbers of consecutive equivalent bits. And

  Moreover, the track circuit device of the present invention is (track 7), the track circuit device of the above solution 4 to 6 which refers to the above solution 1, and the above-mentioned intermittent intermittent threshold is smaller than the above-mentioned intermittent intermittent threshold. It is set to a value.

In such a track circuit device of the present invention (solution means 1 to 3), a drop counter and a saddle counter are provided, and the number of trains and the number of trains are individually counted to detect continuity. The fall time element is divided into the fall time element and the drop time element, and can be individually set. Introducing an intermittent threshold, clears the fall counter when the basic judgment information indicates that there is no train continuously over the number of times of the intermittent threshold value, and the basic judgment information exceeds the number of times of the intermittent threshold value. By clearing the uplift counter when the train is continuously displayed, the continuity smaller than the threshold corresponding to the time element is reflected in the discrimination, while the continuity smaller than the intermittent threshold is reflected. It is suppression that affects discrimination until Since the, so that the function of Tokimoto was for continuity detection is extended to be able to detect up to discontinuities not only continuity detection.
Therefore, according to the present invention, it is possible to realize a track circuit device that can accurately detect a train detection signal up to intermittentness in addition to continuity.

  Further, (Solution 4), the conventional measures for improving the train detection performance described above have advantages and disadvantages, and it can be said that there is room for further improvement. That is, in the case of the bit transmission / reception method, a certain degree of effect can be obtained while suppressing the increase in circuit scale to a slight one, but since only two types of frequencies are used, it has recently become a problem. Frequency-modulating noise, especially alternating noise, is vulnerable to noise, and when such noise enters the track, both illegal fall and illegal dredging can occur. In addition, because narrow band FSK is used, if the complementation verification time is increased in order to increase the accuracy of the complementarity verification, it is not possible to make detailed time setting, so precise train detection can be performed. Disappear. Furthermore, since the verification is performed with complementarity, it is difficult to introduce the concept of bit error rate (BER), and it is difficult to numerically determine the operating rate on the drop / cutter. In addition, since the processing is performed for each bit, a complicated bit pattern verification theory is complicated. Such dissatisfaction lies in the bit transmission / reception system.

On the other hand, in the case of the telegram transmission / reception method, the effect of upgrading the train detection function is high, but the cost and processing speed are unsatisfactory. In other words, since transmission / reception to the track is in telegram units, since the transmission / reception time is longer than in bit units, the time unit / cycle of train detection becomes longer, so the train detection time element cannot be set in detail, Precise train detection is not possible. Furthermore, in an environment where the bit error rate is poor, it is difficult to reduce the frame error rate to a practical value because the entire message becomes invalid if frame synchronization is lost during transmission / reception of the message. Therefore, since it is necessary to employ synchronous detection or the like for the detection circuit, a lot of hardware resources and software resources are required.
Therefore, it is possible to realize an inexpensive track circuit device that is excellent in noise resistance and capable of finely setting time so that the advantages of both the bit transmission / reception method and the message transmission / reception method described above can be enjoyed at the same time. It becomes a technical problem.

In the track circuit device of the present invention (Solution means 4), the frequency modulation that can be realized at low cost has been adopted, and the frame data is repeatedly transmitted without interruption. By performing data processing on a frame-by-frame basis on the receiving side, noise resistance is improved, and the train detection function is enhanced to be comparable to the above-described message transmission / reception method. In addition, since the frame data generation and determination cycle on the receiving side is shorter than the transmission / reception time of the unit frame, the time element setting with the cycle as a unit is now the bit transmission / reception method described above rather than the message transmission / reception method described above. As you get closer, you can do it finely. Moreover, the embodiment can be realized easily and inexpensively by using, for example, a shift register.
Therefore, according to the present invention, it is possible to realize a track circuit device that can accurately detect not only continuity but also discontinuity of a train detection signal, is excellent in noise resistance, and allows fine time setting.

  Furthermore, in the track circuit device of the present invention (solution 5), not only data validity determination in units of frames similar to a telegram transmission / reception system is made possible by utilizing the fact that frame data is repeatedly transmitted and received without interruption. Furthermore, the noise resistance is further improved by performing the validity determination based on the periodicity detection over a plurality of frames.

  In the track circuit device of the present invention (solution 6), a train detection signal generated by frequency modulation is obtained by including in the transmission frame data bit patterns having different numbers of consecutive equivalent bits. However, in that spectrum, it becomes a signal that a plurality of peaks appear even in the sideband of the effective range on one side, and since frequency components that are not crushed by simple alternating noise are clearly retained, it has become a problem in recent years. It can withstand high frequency modulation noise.

  Further, in the track circuit device of the present invention (solution 7), in the determination on a frame basis, if one bit out of a plurality of bits is different, the determination of the train detection is made, so the determination of the train detection is made from the train absent line. In addition, the tendency becomes stronger if the determination in units of frames is performed in a cycle shorter than the transmission / reception time of the unit frame, and if the tendency is too strong, the rising state (the train absent line state) is changed to the falling state ( The decline in train operation rate due to misunderstanding as the train detection state) can no longer be ignored. By making the upside intermittent threshold smaller than the drop intermittent threshold, the above tendency can be eased easily, Moderate operation rate of train operation is secured.

The structure of a track circuit apparatus etc. are shown about Example 1 of this invention, (a) is a block block diagram, (b) is a waveform example of a train detection signal, (c) is a spectrum of a train detection signal. It is a block diagram which shows the structure of a track circuit apparatus about Example 2 of this invention. A conventional track circuit device is shown, (a) is a block diagram, (b) is a waveform example of a train detection signal, and (c) is a spectrum of the train detection signal.

About the track circuit apparatus of this invention, the specific form for implementing this is demonstrated by the following Examples 1-2.
The embodiment 1 shown in FIG. 1 embodies the above-described solving means 1 to 7 (claims 1 to 7 as originally filed), and the embodiment 2 shown in FIG. 2 is a modification thereof. .
In addition, since the same reference numerals are given to the same constituent elements as those in the past in the illustration thereof, and what is described in the background art section is also common to the following embodiments, it is redundant. The description of this will be omitted, and the following description will focus on differences from the prior art.

  A specific configuration of the track circuit device according to the first embodiment of the present invention will be described with reference to the drawings. 1A is a block diagram of the track circuit device 60, FIG. 1B is a waveform example of the train detection signal A, and FIG. 1C is a spectrum of the train detection signal A.

The track circuit device 60 in FIG. 1 (a) is similar to the conventional device 20 in FIG. 3 (a) described above, and a transmission unit that sends a train detection signal A to the corresponding section 12 of the track, and train detection from the section 12. A receiving unit that receives the signal A and detects basic determination information from the received signal, and a logic unit that determines the presence or absence of the train 10 in the section 12 based on the basic determination information, are described below. There are several improvements.
That is, the track circuit device 60 is different from the conventional device 20 in that the track circuit device 60 is different from the conventional device 20 in that the transmission device 30 as the transmission unit is changed to the transmission device 70 and the reception device 40 as the reception unit receives the signal. This is the point that the device 80 is obtained, and in addition, the logic unit 21 is a logic unit 61.

The transmission device 70 is different from the conventional transmission device 30 in that the signal generation circuit 31 is replaced with a signal generation circuit 71. The signal generation circuit 71 is different from the conventional signal generation circuit 31 in that it is frame data. A memory 72 and a frequency modulator 73 (FM modulation) are added.
The difference between the receiving device 80 and the conventional receiving device 40 is that the detection circuit that detects the determination basic information from the received signal has been expanded to become the detection circuit 81. In addition to the level detection circuit 41 that generates the level signal B as one of the determination basic information, a frame detection circuit 82 that generates the reception frame data E as another determination basic information is added.

  The logic unit 61 is different from the conventional logic unit 21 in that it includes a single frame determination circuit 67, a frame periodicity detection circuit 66, a saddle counter 65, a drop counter 64, and a demodulated drop soot determination circuit 63. The reception frame processing circuits 63 to 67 for processing the reception frame data E, the train detection signal F generated by the reception frame processing circuits 63 to 67, and the train detection signal C generated by the level drop droop determination circuit 23 are integrated. And a logical sum operation circuit 62 for generating a final train detection signal G. The track circuit device 60 is also digitized in the same manner as the track circuit device 20. In the track circuit device 60, the logic unit 61, the signal generation circuit 71, and the detection circuit 81 are all FPGAs. (Field Programmable Gate Array) and DSP (Digital Signal Processor).

The frame data memory 72 is a multi-bit nonvolatile memory and holds transmission frame data. The transmission frame data is a bit string composed of a plurality of bits and is a unit frame for transmission. The transmission frame data is read from the frame data memory 72 and serially transferred to the frequency modulator 73 bit by bit. The serial transfer is repeatedly performed without interruption.
The frequency modulator 73 modulates the frequency of the sinusoidal carrier wave generated based on the waveform data of the carrier waveform memory 32 with the transmission frame data serially transferred from the frame data memory 72, so that the train detection signal A An original signal is generated, and this original signal is sent to the pulse width modulator 33.

  The transmission frame data is not necessarily an arbitrary bit string, but is a bit string including bit patterns having different numbers of consecutive equivalent bits. For example, “010011”, “0101010011” (see FIG. 1B), “0101000011000111”, and “101100”, “10101100”, “10101100111000”, etc. obtained by inverting them are preferable. It is done. “01010100” and “11010010” can also be used because they include bit patterns with different numbers of consecutive equivalence bits, but the former is not equal in the number of “0” and “1”, so noise resistance is asymmetrical due to bits. Therefore, the latter cannot be said to be preferable because “11” and “00” are not adjacent to each other, and the dispersibility of the spectral density is not good.

  Furthermore, the optimum transmission frame data also has a property that the cyclic values are all different, that is, the property that the same value does not appear until one cycle is completed when it is circulated bit by bit. For example, when the cyclic value of the 8-bit frame “01010011” is expressed in binary and hexadecimal numbers, “01010011” = “53”, “10100110” = “A6”, “01001101” = “4D”, “ 10011010 ”=“ 9A ”,“ 00110101 ”=“ 35 ”,“ 01101010 ”=“ 6A ”,“ 11010100 ”=“ D4 ”,“ 10101001 ”=“ A9 ”, which are all different.

  The frame detection circuit 82 (see FIG. 1A) performs frequency demodulation (FM demodulation) on the received signal generated by extracting the effective frequency component by the bandpass filter 43 from the train detection signal A that has arrived at the receiving device 80. A frequency demodulator 83 to be applied, a bit reproduction circuit 84 for reproducing a bit string by binarizing the demodulated signal to receive bit data D, and serially inputting the received bit data D to perform serial-parallel conversion Thus, a shift register 85 (SR) for generating received frame data and a first-in first-out buffer 86 for reading received frame data in parallel from the shift register 85 and temporarily storing several frames are provided.

  In this frame detection circuit 82, each time the received bit data D is reproduced by the bit reproduction circuit 84, the received bit data D is input to the shift register 85 bit by bit, and the same as the 1-bit reproduction cycle is appropriately selected. Since the received frame data is transferred from the shift register 85 to the buffer 86 at a multiple frame reproduction period, the received frame data is obtained at a rate of 1 frame per 1 bit transmission / reception time. If the transmission / reception of the train detection signal A is normal as the reception frame data, the cyclic value of the transmission frame data is sequentially reproduced. The temporarily stored data in the buffer 86 is sent to the single frame determination circuit 67 as received frame data E and added to the determination basic information. The transmission may be performed one frame at a time, or may be performed several frames at a time. However, the same restriction as the above frame reproduction cycle is imposed, and the transmission is performed at a cycle shorter than the transmission / reception time of the unit frame. ing.

  The single frame determination circuit 67 processes received frame data as basic determination information. In this process, the validity of the data value is determined for each frame data in units of frames. Specifically, each time the received frame data E is received from the frame detection circuit 82, it is checked whether each received frame data matches one of the cyclic values of the transmission frame data in the frame data memory 72. If it matches any of them, it is judged that the judgment basic information indicates that there is no train, that is, the uphill state (train absent line state). It is determined that the (train detection state) is indicated.

  The frame periodicity detection circuit 66 receives the received frame data processed by the single frame determination circuit 67 from the single frame determination circuit 67 and processes it as determination basic information. In this processing, a plurality of frame data The validity of the periodic change of the data value over the range is determined. Specifically, every time reception frame data is received from the single frame determination circuit 67, if the determination result of the single frame determination circuit 67 is a train, that is, a fall state (train detection state), the contents of the reception frame data are examined. Immediately, the frame periodicity detection circuit 66 also determines that the determination basic information indicates that there is a train, that is, a fall state (train detection state), and the determination result of the single frame determination circuit 67 is that there is no train, that is, the uphill state (train If it is in a standing line state), the contents of the received frame data are examined and determined.

  That is, the frame periodicity detection circuit 66 temporarily stores the reception frame data received immediately before when each reception frame data is normally received in units of frames, and the immediately preceding data and the current reception frame are stored. It is checked whether or not the relationship with the data matches the order of the cyclic values of the transmission frame data. If they match, the judgment basic information is “no train” (OK), that is, the uphill state (the train absent line state) ) Is maintained, but if it does not match, the determination of the single frame determination circuit 67 is reversed and the determination basic information indicates that there is a train (NG), that is, a fall state (train detection state). The judgment is made again.

  By such a frame periodicity detection circuit 66 and a single frame determination circuit 67, the logic unit 61 determines the validity of the data value for each frame data for each frame data when processing the received frame data as the determination basic information. In addition to this, the validity of periodic changes in data values over a plurality of frame data is also determined. In addition, the same restrictions as the frame reproduction period described above are imposed on the frame determination period. For example, the reception frame data can be received in a period shorter than the transmission / reception time of the unit frame only by processing each time reception frame data E is received. Will be processed.

The uplift counter 65 is an incremental counter that counts up every time the frame periodicity detection circuit 66 determines that there is no train (OK), that is, the upright state (train absent line state), and clearing the count value is demodulated. A fall-and-climb judgment circuit 63 is adapted.
The fall counter 64 is an incremental counter that counts up each time the frame periodicity detection circuit 66 determines that there is a train (NG), that is, a fall state (train detection state). The determination circuit 63 is configured to do so.

  The demodulated drop-up / down determination circuit 63 generates the train detection signal F based on the count values of the drop counter 64 and the up-counter 65, and when the value of the up-counter 65 exceeds the up / down time corresponding threshold value. The train absence line is determined to change the value of the train detection signal F to the train absent line state, and when the value of the fall counter 64 exceeds the falling time corresponding threshold, the train detection determination is issued and the value of the train detection signal F is set. Set to the state of train detection. Furthermore, in addition to the falling threshold value, the falling intermittent threshold value is also referred to, and the frame periodicity detection circuit 66 determines whether there is no train (OK), that is, the uphill state (train absent line state). The drop counter 64 is cleared and the count value is returned to zero when it is continuously output over the number of times of the drop continuity threshold.

Further, the demodulating drop-up determination circuit 63 refers to the drop-up intermittent threshold value in addition to the drop-off time corresponding threshold value, and from the frame periodicity detection circuit 66, there is a train (NG), that is, a drop. When the determination of the state (train detection state) continues continuously for the number of times of the up / down intermittent threshold, the up counter 65 is cleared and the count value is returned to zero.
In the level drop soot judgment circuit 23, the element when dropping and the element when soaking are determined in advance as 500 ms or 1000 ms to 1100 ms as described above. In the reception frame processing circuits 63 to 67 of the stand, the fall time element is preferably set to the same 500 ms, but the uplifting element is set to a shorter value, for example, 800 ms.

An integer value calculated by dividing such a time element by a 1-bit transmission / reception time is selected as the time element correspondence threshold value, but a value that is 1 or more and smaller than the fall time element correspondence threshold value is selected as the drop interruptability threshold value. In addition, a value that is 1 or more and smaller than the lifting time element correspondence threshold is selected as the up / down intermittent threshold, and further, the up / down intermittent threshold is selected to be smaller than the falling intermittent threshold.
The logical sum operation circuit 62 generates a train detection signal G from the train detection signal C and the train detection signal F by logical sum, and one or both of the train detection signals C and F are in a fall state (train In the case of the detection state), the train detection signal G is set to the fall state (train detection state), and only when the train detection signals C and F are both in the uphill state (train absent line state) Absent line state).

The usage mode and operation of the track circuit device 60 of the first embodiment will be described.
When the track circuit device 60 is installed, the transmitter 70 is connected to one end of the section 12 of the track via the transformer 36, the cable 37, and the transformer 38, and the receiver 80 is connected via the transformer 46, the cable 47, and the transformer 48. And connected to the other end of the track section 12.

  When the track circuit device 60 is activated, the logic unit 61 clears the drop counter 64 and the uplift counter 65, and can be frequency-discriminated from other sections by initialization by the initial setting circuit 22 of the logic unit 61. Waveform data of a sine wave having the frequency fo is set in the carrier waveform memory 32, and the lower limit frequency fa and the upper limit frequency fb are set in the band pass filter 43. The upper and lower limit frequencies fa and fb (see FIG. 1C) are determined so as to include an effective sideband of the train detection signal A around the carrier frequency fo.

  After initialization, the signal generation circuit 71 of the transmission device 70 generates a sine wave carrier wave based on the waveform data in the carrier waveform memory 32, and at the same time, the transmission frame data is interrupted from the frame data memory 72. Without being repeated, and the frequency modulator 73 frequency-modulates the carrier wave with the transmission frame data. Then, it is sent to the track section 12 as the train detection signal A by the power amplifier 34, the low-pass filter 35, the cables 36-38 and the like.

  For example, if the carrier frequency fo of the carrier wave is 5000 Hz, the frequency shift is 16 Hz, the transmission frame data is 8 bits “01010011” = “53” (see FIG. 1B), and the bit rate is 64 bps, the train detection signal The 1-bit transmission / reception time for A is 15.625 ms, and the transmission / reception time for a unit frame is 125 ms. This is only a fraction of the drop time element 500 ms and the drop time element 800 ms of the demodulating drop-up determination circuit 63 and is sufficiently short. In addition, in the sideband of the train detection signal A (see FIG. 1C), many effective peaks appear on one side. This is because the transmission frame data includes the bit pattern “01” and the bit pattern “0011”, and the number of consecutive identical bits is different between the two.

  The train detection signal A is almost transmitted to the other end of the track section 12 when the train 10 is traveling in the track section 12 and the transmission of the signal is cut off due to a rail short circuit on the wheel or axle. However, when the train 10 has advanced from the track section 12, it reaches the other end of the track section 12 with a large amplitude and is received by the receiving device 80 via cables 46 to 48. In the receiving device 80, the received signal of the train detection signal A is converted from an analog signal to a digital signal by the power amplifier 45 and the A / D converter 44 and input to the detection circuit 81, and by the level detection of the level detection circuit 41, A level signal B is generated as one piece of basic judgment information.

Then, in the logic unit 61, the train detection signal C is generated from the level signal B as described above by the level drop soaring determination circuit 23. The generation of the level signal B and the generation of the train detection signal C are performed at any time while receiving the train detection signal A as in the prior art.
In addition, in the detection circuit 81 of the receiving device 80, the frame detection process by the frame detection circuit 82 is also performed in parallel with the level detection. This frame detection is also performed while receiving the train detection signal A, but is performed at a cycle of 1-bit transmission / reception time of 15.625 ms or an integral multiple thereof and shorter than the transmission / reception time of the unit frame of 125 ms.

  More specifically, an effective frequency component is extracted from the received signal of the train detection signal A by the band pass filter 43, subjected to frequency demodulation by the frequency demodulator 83, and further binarized by the bit reproduction circuit 84. Received bit data D is generated by reproduction, and the received bit data D is serial-parallel converted by the shift register 85 every time one bit is reproduced, thereby obtaining transmission frame data. This data is temporarily stored in the buffer 86 in a first-in first-out manner, and is sent to the single frame determination circuit 67 of the logic unit 61 as received frame data E every three frames in a cycle shorter than the transmission / reception time of 125 ms, for example, 3 bits transmission / reception time 46.875 ms. Transferred.

  The reception frame data E is a repetition of the cyclic value when the transmission frame data “01010011” can be normally received. When expressed in hexadecimal, 53, A6, 4D, 9A, 35, 6A, D4, A9, 53 , A6,. Then, the validity of the data value is determined for each frame data by the single frame determination circuit 67 in units of frames, and the validity of the periodic change of the data value over a plurality of frame data is determined by the frame periodicity detection circuit 66. Only when both are judged to be valid, it is judged that the judgment basic information indicates that there is no train (OK), that is, the uphill state (train absent line state), and the count value of the uplift counter 65 Is incremented by one.

  On the other hand, if either one is not valid, it is determined that the determination basic information indicates that there is a train (NG), that is, a falling state (train detection state), and the count value of the falling counter 64 is incremented by one. The Such determination in units of frames and counting of the determination results are also processed continuously for every 3 bits for every 3 bits transmission / reception time 46.875 ms. This is the actual time setting unit time for the falling element and the flying element. This is considerably shorter than the unit frame transmission / reception time of 125 ms. If the transfer of the received frame data E from the buffer 86 to the single frame determination circuit 67 is performed every time one frame is reproduced, the time set unit time becomes a much shorter 1-bit transmission / reception time of 15.625 ms, It is possible to set the time element in the finest detail.

  Then, the demodulated drop hoist judgment circuit 63 in which the count value of the fall counter 64 exceeds the falling prime correspondence threshold value causes the train detection signal F to be in a train detection state, and the count value of the uplift counter 65 is the threshold value corresponding to the prime fall prime correspondence threshold value. When the value exceeds the value, the value of the train detection signal F is set to a train absent line state by the demodulating drop-up determination circuit 63, but the count value does not increase monotonously, and the received frame data E is not trained (OK), that is, When the determination of the uphill state (the train absent line state) is continuously issued over the number of times of the drop continuity threshold, the count value of the drop counter 64 is returned to zero, and there is a train for the received frame data E (NG), When the determination of the falling state (train detection state) is continuously made over the number of times of the lifting intermittent threshold value, the count value of the lifting counter 65 is returned to zero.

Thus, the train detection signal F is generated as another determination basic information, and the final train detection signal G is generated from the train detection signal F and the level signal B described above by the operation of the logical sum operation circuit 62.
Such signal processing is repeated in the track circuit device 60 from the start to the stop of the device, and the train detection signal A is transmitted and received through the track section 12, and the train detection signal A is received based on the received signal. Train detection by level detection and train detection by frame determination are performed.

  That is, when the train 10 advances from the track section 12, the train detection signal A is transmitted from the transmission device 70 to the reception device 80 as described above, and therefore the value of the level signal B becomes larger than a predetermined value. Since the train detection signal C indicates that there is no train, the reception frame data E also continues to be valid, and the train detection signal F also indicates that there is no train. Therefore, the train detection signal G accurately indicates that there is no train. . On the other hand, when the train 10 enters the section 12 of the track, the transmission of the train detection signal A is interrupted as described above. Therefore, if there is no excessive noise, the value of the level signal B is lower than the predetermined value. Thus, the train detection signal C indicates that there is a train, and the received frame data E is not valid, and the train detection signal F also indicates that there is a train. Therefore, the train detection signal G accurately indicates the presence of a train.

  In addition, even when the train 10 enters the track section 12 and the transmission of the train detection signal A is cut off, a large level of noise comparable to or exceeding the train detection signal A has entered the track section 12. In this case, the value of the level signal B becomes greater than a predetermined value in response to the noise, and the train detection signal C indicates no train, but the noise is an example of alternating frequency modulation that has recently become a problem. Even if it is noise, the train detection signal A (see FIG. 1 (c)) in which there are a plurality of effective peaks in only one sideband in the spectrum and the noise are incorrect over a period of time that is greater than or equal to the amount of time. As the determination continues, the probability of matching is very small, so the received frame data E is not valid, and the train detection signal F indicates the presence of a train, so the train detection signal G accurately indicates the presence of a train. And this greatly increases the safety of train operation.

  Further, when the train 10 advances from the track section 12, the train detection signal A is transmitted from the transmitting device 70 to the receiving device 80. However, when noise that disturbs the signal waveform is on, the waveform is disturbed. If the level is maintained, the value of the level signal B becomes larger than the predetermined value, and the train detection signal C indicates no train, but if the waveform of the train detection signal A is disturbed, the received signal is undesired. Since bit corruption and bit value inversion occur and the validity of the received frame data E is impaired, the train detection signal F indicates the presence of a train, and therefore the train detection signal G erroneously indicates the presence of a train. This misjudgment is not fatal because it is safe, but it is not preferable because it reduces the operating rate of train operation, and many are avoided as described below.

  In other words, the count value of the drop counter 64 is reset to zero if the received frame data E is valid (OK) continuously for the number of times of the drop continuity threshold before it reaches the drop correspondence threshold. It is. In addition, the count value of the uplift counter 65 is not valid (NG) when the received frame data E is not valid continuously over the number of times of the upside intermittent threshold before it reaches the uplift time corresponding threshold value (NG). Set back to zero. In addition, with respect to such a count, a condition is imposed that the suspending intermittent threshold is smaller than the falling intermittent threshold. Therefore, even if undesired bit corruption and bit value inversion occur in the received signal of the train detection signal A, the validity of the received frame data E is maintained unless the frequency is high.

In order to explain with a numerical example, the uplifting element correspondence threshold is “48”, the upside discontinuity threshold is “1”, the falling out correspondence threshold is “48”, and the drop intermittence threshold is “16”. Suppose there is. Further, when the result of determination by the single frame determination circuit 67 and the frame periodicity detection circuit 66 is valid (OK), it is indicated by ◯, and when it is invalid (NG), it is indicated by ×.
And if it is judged that ○… ○ ×… × ○… ○ ×… ×, in the basic state with no noise, each ○… ○ and ×… × is a series of 48 or more. After 48 frames, the train detection signal F enters a fall state (train detection state), and after 48 frames from the 列車, the train detection signal F enters an uphill state (a train absent line state).

In addition, even if it is shredded, if it is judged inappropriate (NG) repeatedly in a short period of time, for example, OO X X X X X X X X X X X X X X ○○○○ × ○○○ × ○○○ × ○○○ × ○○ × ○○○ × ○○○ × ○○○○ × ○○○ × ○○○○ × ○○○○○○… In such a case, the count value of the drop counter 64 increases without being cleared, and the train detection signal F eventually falls (train detection state). Safety is important for such intermittentness.
On the other hand, when the train detection signal F is in the uphill state (train absent line state), if the determination of invalidity (NG) jumps out, for example, OOXXXXX XXXX ○○○○○○○○○○○○○○○ ×× ○○○ × ○○○○○○○○○○○○○○○○ × ○○○○ ×× ○○○ In the case of ◯◯◯..., The count value of the drop counter 64 is cleared from time to time and cannot be increased up to the threshold value corresponding to the drop time element, so the train detection signal F does not enter the fall state (train detection state). With such discontinuity, the operation rate can be secured.

  The track circuit device 90 whose block configuration diagram is shown in FIG. 2 is different from the track circuit device 60 of the first embodiment described above in that the logic unit 61 is modified to be a logic unit 91. The logic unit 61 is different from the logic unit 61 in that the function of the initial setting circuit 22 is expanded to become the initial setting circuit 92, and the level signal processing in which the level drop soaring determination circuit 23 detects not only continuity but also continuity. The circuit 93-96.

  The initialization circuit 92 is configured to set transmission frame data in addition to performing the same processing as the initialization circuit 22 described above during initialization. The setting destination is the frame data memory 72 and the single frame determination circuit 67, and the setting value to the single frame determination circuit 67 is also referred to by the frame periodicity detection circuit 66. Transmission frame data is input to the initial setting circuit 92 only when necessary using, for example, an 8-bit DIP switch or a temporary connection adjusting jig, and transmission frame data having the same value is repeatedly used in a steady state. The Since the signal separation between the orbital section 12 and the other sections 11 and 13 is performed by frequency discrimination by the carrier waveform memory 32 and the bandpass filter 43, the transmission frame data may be the same as or different from the apparatus in the other sections. May be. Therefore, the transmission frame data can be changed according to the resistance to noise that rides on the orbital section 12.

  The level signal processing circuits 93 to 96 count the number of times each time the level determination circuit 96 determines whether or not the amplitude level of the level signal B is appropriate in a predetermined cycle, and the level determination circuit 96 determines that the level is good (OK). An upper counter 95, a drop counter 94 that counts the number of times each time a level deficiency (NG) determination is made from the level determination circuit 96, and a level drop that generates a train detection signal C based on the count values of both counters 94 and 95 And an uplift determination circuit 93. The level determination cycle by the level determination circuit 96 may be the same 125 ms as the single frame determination circuit 67, or may be another time length.

  Similar to the demodulated drop-up / up determination circuit 63, the level drop-up / down determination circuit 93 issues a train absent line determination and determines the value of the train detection signal C when the value of the up / down counter 95 exceeds the up / down time corresponding threshold value. When the train is absent, and the value of the drop counter 94 exceeds the falling threshold, the train detection is determined and the value of the train detection signal C is set to the train detection state. Further, in addition to the falling threshold value, a drop continuity threshold value smaller than that is also referred to, and the level determination circuit 96 makes a determination of good level (OK) continuously over the number of times of the drop continuity threshold value. When exiting, the fall counter 94 is cleared and its count value is returned to zero.

Further, the level drop up / down determination circuit 93 refers to the up / down intermittent threshold value having a smaller value in addition to the up / down time corresponding threshold value, and the level determination circuit 96 determines that the level is insufficient (NG). When it is continuously output over the number of times of the upper intermittent threshold value, the upper counter 95 is cleared and its count value is returned to zero.
In the level drop soot judgment circuit 93, the fall time element and the soaring time element are set to 500 ms and 1000 ms to 1100 ms like the level drop soot judgment circuit 23, and such time base is divided by the level judgment cycle. Although the selected integer value is selected as the threshold value for the time element, a value that is 1 or more is selected as the drop intermittent threshold value, and a value that is smaller than the threshold value for the falling element is selected. A value smaller than the upper hour correspondence threshold is selected.

  In this case, since the determination method reflecting not only the continuity but also the discontinuity is applied to the level determination in addition to the determination in the frame unit, the tolerance to intermittent noise is increased. In addition, in the level judgment, it is not so easy to make the train detection judgment as much as the judgment in the frame unit, so it is not important to make the upside intermittent threshold value smaller than the fall down intermittent threshold value. The threshold value and the fall / intermittent threshold value are determined according to the balance between safety and operating rate.

[Others]
In the above embodiment, the track circuit devices 60 and 90 are divided into three units of the logic units 61 and 91, the transmission device 70, and the reception device 80, but this unit division is not essential for the implementation of the present invention, and one unit or two They may be grouped into units, or subdivided into four or more units.

10 ... train, 11, 12, 13 ... section of track,
20 ... Track circuit device, 21 ... Logic part,
22 ... Initial setting circuit, 23 ... Level drop-up determination circuit,
30 ... Transmitting device (transmitting unit), 31 ... Signal generating circuit,
32 ... Carrier waveform memory, 33 ... Pulse width modulator (PWM),
34 ... Power amplifier (AMP), 35 ... Low pass filter (LPF),
36 ... Transformer (MT), 37 ... Cable, 38 ... Transformer (MT),
40 ... receiving device (receiving unit), 41 ... level detection circuit,
42 ... Rectifier, 43 ... Band pass filter (BPF),
44 ... A / D converter (ADC), 45 ... Power amplifier (AMP),
46 ... Transformer (MT), 47 ... Cable, 48 ... Transformer (MT),
60 ... Track circuit device,
61 ... logic unit, 62 ... logical sum operation circuit,
63: Demodulation drop soot judgment circuit, 64 ... Fall counter, 65 ... Soot counter,
66 ... frame periodicity detection circuit, 67 ... single frame determination circuit,
70: Transmitter (transmitter), 71: Signal generation circuit,
72: Frame data memory, 73: Frequency modulator (FM),
80: receiving device (receiving unit), 81: detecting circuit,
82: Frame detection circuit, 83: Frequency demodulator (FM),
84: Bit reproduction circuit, 85: Shift register (SR), 86: Buffer,
90 ... Track circuit device,
91: Logic unit, 92: Initial setting circuit,
93: Level drop soot judgment circuit, 94 ... Drop counter,
95 ... Upper counter, 96 ... Level determination circuit

Claims (6)

A transmission unit that transmits a train detection signal to a corresponding section of the track, a reception unit that receives the train detection signal from the section and detects determination basic information from the reception signal, and the section based on the determination basic information In a track circuit device having a logic unit for determining the presence or absence of a train,
The logic unit includes a fall counter that counts the number of times that the basic determination information indicates that there is a train, and an uplift counter that counts the number of times that the basic determination information indicates that there is no train. If the value exceeds the jack up time element corresponding threshold out a determination of absence of train lines, the value of the drop counter is intended to leave the determination of train detection exceeds the fall time element corresponding threshold,
In other words, the logic unit clears the drop counter when the determination basic information indicates that there is no train continuously for the number of times of the drop continuity threshold value that is smaller than the fall time element correspondence threshold value, When the judgment basic information indicates that there is a train continuously for the number of times of the up / down intermittent threshold value smaller than the up-time element correspondence threshold, clearing up the up- counter , either one or both It is adapted to do that,
The transmission unit is configured to generate the train detection signal by frequency-modulating a carrier repeatedly and repeatedly with transmission frame data having a bit string composed of a plurality of bits as a unit frame, and the reception unit is Generating received frame data by extracting a plurality of bits from a bit string reproduced by frequency demodulation at a frame reproduction period shorter than the transmission / reception time of the unit frame, and including the received frame data in the determination basic information; state, and are not to process the received frame data in a short frame determination period from reception times of the unit frame,
Further, when the logic unit processes the received frame data, in addition to determining the validity of the data value for each frame data for each frame, the logic unit periodically changes the data values over a plurality of frame data. also validity characterized in that it is adapted to determine orbit circuit device. A transmission unit that transmits a train detection signal to a corresponding section of the track, a reception unit that receives the train detection signal from the section and detects determination basic information from the reception signal, and the section based on the determination basic information In a track circuit device having a logic unit for determining the presence or absence of a train,
The logic unit includes a fall counter that counts the number of times that the basic determination information indicates that there is a train, and an uplift counter that counts the number of times that the basic determination information indicates that there is no train. If the value exceeds the jack up time element corresponding threshold out a determination of absence of train lines, the value of the drop counter is intended to leave the determination of train detection exceeds the fall time element corresponding threshold,
In other words, the logic unit clears the drop counter when the determination basic information indicates that there is no train continuously for the number of times of the drop continuity threshold value that is smaller than the fall time element correspondence threshold value, When the judgment basic information indicates that there is a train continuously for the number of times of the up / down intermittent threshold value smaller than the up-time element correspondence threshold, clearing up the up- counter , either one or both It is adapted to do that,
The transmission unit is configured to generate the train detection signal by frequency-modulating a carrier repeatedly and repeatedly with transmission frame data having a bit string composed of a plurality of bits as a unit frame, and the reception unit is Generating received frame data by extracting a plurality of bits from a bit string reproduced by frequency demodulation at a frame reproduction period shorter than the transmission / reception time of the unit frame, and including the received frame data in the determination basic information; state, and are not to process the received frame data in a short frame determination period from reception times of the unit frame,
Furthermore, orbital circuit device characterized in that the transmission frame data contains a continuous number of different bit patterns of the equivalence bits. 2. The track circuit device according to claim 1, wherein the transmission frame data includes bit patterns having different numbers of consecutive equivalent bits. A transmission unit that transmits a train detection signal to a corresponding section of the track, a reception unit that receives the train detection signal from the section and detects determination basic information from the reception signal, and the section based on the determination basic information In a track circuit device having a logic unit for determining the presence or absence of a train,
The logic unit includes a fall counter that counts the number of times that the basic determination information indicates that there is a train, and an uplift counter that counts the number of times that the basic determination information indicates that there is no train. If the value exceeds the threshold value corresponding to the falling element, the absence line of the train is determined, and if the value of the falling counter exceeds the threshold value corresponding to the falling element, the detection of the train is detected. When the judgment basic information indicates that there is no train continuously over the number of times of the sex threshold, the fall counter is cleared, and continuously over the number of times of the up / down intermittent threshold value that is smaller than the upside time corresponding threshold value. When the basic judgment information indicates that there is a train, the uplift counter is cleared .
The transmission unit is configured to generate the train detection signal by frequency-modulating a carrier repeatedly and repeatedly with transmission frame data having a bit string composed of a plurality of bits as a unit frame, and the reception unit is Generating received frame data by extracting a plurality of bits from a bit string reproduced by frequency demodulation at a frame reproduction period shorter than the transmission / reception time of the unit frame, and including the received frame data in the determination basic information; state, and are not to process the received frame data in a short frame determination period from reception times of the unit frame,
Furthermore, the jack up orbital circuit device you characterized by discontinuities threshold is set to the drop saccadic smaller than the threshold value.   In the processing of the received frame data, the logic unit determines the validity of the data value for each frame data in units of frames, and the validity of the periodic change of the data values over a plurality of frame data The track circuit device according to claim 4, wherein the track circuit device is also determined.   The track circuit device according to claim 4 or 5, wherein the transmission frame data includes bit patterns having different numbers of consecutive equivalent bits.

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