JP2014200134A - Train controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a train controller capable of setting a sampling frequency low, reducing the number of taps of a correlation calculation, and appropriately detecting a carrier wave phase difference.SOLUTION: A train controller comprises: a ground device 1 performing an amplitude modulation process on a phase modulation signal on the basis of predetermined train control information, and transmitting the resultant signal to an on-vehicle device 3; and the on-vehicle device 3 including a phase detection circuit 5 outputting phase information from the amplitude modulation signal transmitted from the ground device 1. The phase detection circuit 5 calculates a correlation between a plurality of carrier wave waveform data in preset phases shifted and a carrier wave of the amplitude modulation signal transmitted from the ground device 1, and detecting a phase of the carrier wave of the amplitude modulation signal.

Description

  The present invention relates to a train control device, and more particularly, to a train control device that can set a sampling frequency low and reduce the number of correlation calculation taps to appropriately detect a carrier phase difference. .

  Conventionally, in a train control device according to ATC, it is composed of a ground device provided on the ground side and an on-board device mounted on the train side, and transmits a predetermined train control signal from the ground device to the train, The transmitted train control signal is received by the on-board device, and predetermined train control such as speed control is performed.

  In such a train control device, a technique has been developed that allows a plurality of information to be transmitted to the vehicle upper side by changing the phase of a carrier wave of an amplitude-modulated wave used as a train control signal. .

  As such a train control device, conventionally, for example, a phase modulation processing means provided in a ground device that modulates the phase of a carrier wave with a predetermined phase corresponding to sub information different from main information, and a signal received from the ground device Train by a combination of phase detection means provided in the on-board device for detecting the phase of the vehicle, sub-information extraction means for extracting the sub-information corresponding to the detected phase, and the main information based on the extracted sub-information The technique provided with the train control means which controls is disclosed (for example, refer to patent documents 1).

JP 2008-013043 A

  However, in the prior art, since the phase difference is obtained from the time difference between the maximum values of the correlation values by the phase detection means, it is necessary to determine the maximum value of the correlation values. There is a problem that the sampling frequency needs to be higher than the target carrier frequency in proportion to the accuracy of identifying the phase difference, and the correlation calculation tap value needs to be increased accordingly. In addition, when the frequency of the carrier wave of the amplitude-modulated wave is high, the sampling frequency is also high, so improvement has been demanded.

  The present invention has been made in view of the above points, and train control that can set the sampling frequency low and reduce the number of taps for correlation calculation to properly detect the phase difference of the carrier wave. The object is to provide an apparatus.

In order to achieve the above object, the train control device according to the invention of claim 1 includes a ground device that performs amplitude modulation processing of a phase modulation signal based on predetermined train control information and transmits the signal to an onboard device; An on-board device comprising phase detection means for outputting phase information from the amplitude modulation signal transmitted from the ground device,
The phase detection means detects a phase of the carrier wave of the amplitude modulation signal by calculating a correlation between a plurality of carrier waveform data having a preset phase shift and the carrier wave of the amplitude modulation signal transmitted from the ground device. It is characterized by doing.

  According to a second aspect of the present invention, in the first aspect, a plurality of the phase detection means are provided according to each carrier waveform data with the phase shifted.

  According to the first aspect of the present invention, the phase detection means performs correlation calculation between a plurality of carrier waveform data whose phases are shifted in advance and the carrier wave of the amplitude modulation signal transmitted from the ground device, and the amplitude modulation signal Therefore, by calculating the correlation between a plurality of carrier waveform data whose phases are shifted and the input carrier waveform, the correlation calculation can be performed without increasing the sampling frequency. Even when the tap value is small, the maximum value of the correlation value can be detected appropriately.

  According to the second aspect of the present invention, since a plurality of phase detection means are provided according to each carrier waveform data whose phase is shifted, carrier waveform data whose phase is shifted is set for each phase detection means. Sampling based on the correlation value output for each phase detection means by calculating the correlation between a plurality of carrier waveform data whose phases are shifted in advance and the carrier wave of the amplitude modulation signal transmitted from the ground device Even if the tap value for correlation calculation is small without increasing the frequency, the maximum value of the correlation value can be detected appropriately.

It is a schematic structure figure showing an embodiment of a train control device concerning the present invention. It is explanatory drawing which shows the waveform example of the amplitude modulation wave in embodiment of the train control apparatus which concerns on this invention. It is a block diagram which shows the phase detection circuit in embodiment of the train control apparatus which concerns on this invention. It is a block diagram which shows the soot digital correlator in embodiment of the train control apparatus which concerns on this invention.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is a schematic configuration diagram illustrating an embodiment of a train control device according to the present invention. In FIG. 1, the train control device of the present embodiment includes a ground device 1 provided on the ground side and a train 2. And an on-vehicle device 3 mounted thereon. And the figure of the rail of the track circuit T in which the train 2 traveling in the right direction in the figure shows a train control signal corresponding to the train control information such as the allowable speed information of the train 2 from the ground device 1. When the on-board device 3 receives the train control signal transmitted from the middle right end side, the train control information is extracted from the train control signal, and the traveling of the train 2 is controlled based on the extracted train control information. Yes. The track circuit is formed by rails, and is electrically insulated from the rails forming the front and rear track circuits T ′ and T ″ with respect to the AC signal.

  The ground device 1 is configured to generate a modulated wave by performing amplitude modulation processing on a basic carrier wave having a predetermined frequency to form a train control signal indicating predetermined train control information. Thus, the train control signal subjected to the amplitude modulation processing is configured to be amplified and supplied to the rails forming the track circuit T. Such a ground device 1 is also provided in each adjacent track circuit T ′, T ″, but is omitted here.

  FIG. 2 is a waveform example of a train control signal transmitted from the ground device 1. The waveform in FIG. 2 is a train control signal obtained by amplitude-modulating a phase-modulated signal whose phase is advanced for each signal portion (mark) intermittent to the basic carrier wave. In FIG. 2, A, B, and C indicate signal portions (marks) where the train control signal (amplitude modulation signal) is intermittent.

  Next, the on-board device 3 will be described.

  The on-board device 3 is provided facing the rail at the front part of the train 2 and receives a train control signal transmitted from the ground device 1 to the rail, and a phase detection means for inputting the received train control signal. As a phase detection circuit 5.

  In FIG. 3, the phase detection circuit 5 of the present embodiment includes an A / D converter 6, a digital correlator 7, and a phase difference detection circuit 8.

  The A / D converter 6 samples the received analog train control signal (amplitude modulation signal) at a predetermined interval and converts it into a digital signal, and outputs the converted digital train control signal (amplitude modulation signal) as sampling data. It is configured as follows.

  The digital correlator 7 is based on the sampling data input from the A / D converter 6 and each carrier wave in each signal portion (mark) A, B, C of the train control signal (amplitude modulation signal) shown in FIG. And the basic carrier wave correlation value. In this embodiment, a plurality of digital correlators 7 are provided, and each digital correlator 7 is connected to the A / D converter 6 in parallel.

  As shown in FIG. 4, each digital correlator 7 includes a shift register 9 to which sampling data is input, a coefficient storage unit 10, multipliers 11-1 to 11 -N, and an adder 12. Yes. The shift register 9 has a number of shift stages I (1) to I (N) that can store sampling data constituting waveform data for one period of the basic carrier wave, and is configured to sequentially shift. Here, (360 ° / number of shift stages) is the minimum detectable phase difference, and the number of shift stages affects the detection resolution of the phase difference.

  The coefficient storage unit 10 stores the waveform data for one cycle of the internal carrier as multiplication coefficients A (1) to A (N) corresponding to the number of shift stages of the shift register 9. For example, when the number of shift stages is 36, the number of multiplication coefficients (A1) to A (N) is also 36. In this case, the multiplication coefficients A (1) to A (N) are used as one cycle (360) of the internal carrier wave. The amplitude value at every 10 ° in (°) is stored.

  Further, N multipliers 11-1 to 11 -N are provided corresponding to the number N of shift stages of the shift register 9, and the sampling data of each shift stage I (1) to I (N) of the shift register 9 is used as the sampling data. It is configured to multiply the corresponding multiplication coefficients A (1) to A (N) of the coefficient storage unit 10 respectively. The adder 12 is configured to output a correlation value indicating the degree of correlation between the phase-modulated carrier wave and the internal carrier wave (basic carrier wave) inputted by adding the multiplication results of the multipliers 11-1 to 11 -N. ing. Then, sampling data for one cycle of the input carrier is sequentially shifted, and when the phase of the input carrier coincides with the phase of the internal carrier, the correlation value becomes a maximum value. There will be a correlation value maximum position for each period.

  Further, in the present embodiment, the coefficient storage unit 10 of each digital correlator 7 is configured to store the phase of the waveform data for one period of the internal carrier wave with a shift. For example, assuming that N digital correlators 7 are provided, the digital correlator (1) 7 is configured so that the phase of the waveform data of the internal carrier is stored at 0 °, that is, as it is. (2) In 7, the phase of the waveform data of the internal carrier is stored so as to be shifted by 360 ° / N. For example, if N = 36, the phase shift of the internal carrier waveform data of each digital correlator 7 is 10 °, and the coefficient storage unit 10 of each digital correlator 7 is shifted by 10 °. The waveform data of the internal carrier wave having the same phase is stored.

  The phase difference detection circuit 8 detects the maximum position of the correlation value based on the correlation value output from each digital correlator 7, and between adjacent signal portions based on the maximum position data of the correlation value. It is configured to detect the relative phase difference of the carrier wave between the adjacent signal portions by calculating the difference between the maximum positions.

  Here, in this embodiment, each correlation value output from each digital correlator 7 is obtained by multiplying the waveform data of the input carrier by the waveform data of the internal carrier stored in the coefficient storage unit 10. Therefore, the correlation value of the digital correlator 7 whose coefficient is the waveform data of the internal carrier wave close to the phase of the input carrier wave waveform is a value close to the maximum value. In this way, by storing a coefficient in which the phase of the waveform data of the internal carrier wave is shifted in each digital correlator 7, it is possible to properly correlate without increasing the sampling frequency and even when the correlation calculation tap value is small. The maximum value of the value can be detected.

  Then, for example, as shown in FIG. 4, the phase difference detection circuit has a correlation output i among the correlation values 0 to N−1 output from each digital correlator 7 in the signal portion (mark) of the train control signal. Assuming that the maximum value is output at the next signal portion (mark) and the maximum value is output at the correlation output j, the phase difference between the correlation output i and the correlation output j is the phase difference of the received signal to be obtained.

  Next, operation | movement of the phase detection circuit 5 in the train control apparatus of this embodiment is demonstrated.

  When the amplitude modulation signal received by the power receiver 4 is input to the phase detection circuit 5, it is sampled at a predetermined interval by the A / D converter 6, and the sampling data of the digital signal is sequentially input to each digital correlator 7. Then, in the digital correlator 7, the input sampling data is sequentially shifted by the shift register 9, and the sampling data I (1) to I (N (N) of each shift stage of the shift register 9 by the multipliers 11-1 to 11-N. ) And multiplication coefficients A (1) to A (N) stored in the coefficient storage unit 10. The multiplication results of the multipliers 11-1 to 11 -N are added by the adder 12 to calculate a correlation value, and the calculated correlation value is input to the phase difference detection circuit 8.

  Then, based on the correlation output outputted from each digital correlator 7 by the phase difference detection circuit, it is detected which correlation value from which digital correlator 7 becomes the maximum value, and the maximum value in each signal portion is detected. The phase difference is detected by obtaining the phase difference from the correlation output.

  In this embodiment, the signal detection is normally performed by confirming that the maximum value of the correlation output is periodically output from one of the digital correlators 7 in one signal portion (mark). You can see what is happening.

  As described above, in this embodiment, the phase of the waveform data for one cycle of the internal carrier wave is shifted and stored in the coefficient storage unit 10 of each digital correlator 7. When the correlation value of the digital correlator 7 whose coefficient is the waveform data of the internal carrier wave close to the phase is output, a value close to the maximum value is output, and the sampling frequency is not increased and the correlation calculation tap value is small. However, there is an effect that the maximum value of the correlation value can be detected appropriately.

  In the above embodiment, a plurality of digital correlators 7 are provided, and the waveform data of the internal carrier whose phase is shifted is stored in the coefficient storage unit 10 of each digital correlator 7. In the correlator 7, waveform data obtained by shifting the phase of the internal carrier wave is stored in the coefficient storage unit 10, and correlation calculation is performed based on the waveform data in each phase and the input carrier wave waveform. A local maximum value may be detected.

  The present invention is not limited to the above-described embodiment, and various modifications can be made based on the gist of the present invention.

DESCRIPTION OF SYMBOLS 1 Ground apparatus 2 Train 3 On-board apparatus 4 Power receiver 5 Phase detection circuit 6 A / D converter 7 Digital correlator 8 Phase difference detection circuit 9 Shift register 10 Coefficient storage part 11 Multiplier 12 Adder

Claims (2)

A vehicle including a ground device that performs amplitude modulation processing on a phase modulation signal based on predetermined train control information and transmits the signal to the on-vehicle device, and a phase detection unit that outputs phase information from the amplitude modulation signal transmitted from the ground device. An upper device,
The phase detection means detects a phase of the carrier wave of the amplitude modulation signal by calculating a correlation between a plurality of carrier waveform data having a preset phase shift and the carrier wave of the amplitude modulation signal transmitted from the ground device. A train control device.   The train control apparatus according to claim 1, wherein a plurality of the phase detection means are provided according to each carrier waveform data with the phase shifted.

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